RAPID ENVIRONMENTAL IMPACT...
Transcript of RAPID ENVIRONMENTAL IMPACT...
RAPID ENVIRONMENTAL IMPACT ASSESSMENT
FOR
THE PROPOSED AUGMENTATION & EXPANSION OF EXISTING
THERMAL POWER PLANT
BY
M/s. ARS Metals Pvt. Ltd. Chennai, Tamil Nadu
AT Sithurnatham, Sirupuzhalpettai & Eguvarapalayam villages ,
Gummidipoondi taluk, Thiruvallur district, Tamil Nadu
Project Proponent
M/s. ARS Metals Pvt. Ltd. Chennai, Tamil Nadu
EIA Consultant
M/s. Vimta Labs Limited Hyderabad / Coimbatore
QCI/NABET Accredited EIA Consultant
FINAL EIA REPORT
JULY 2015
For and on behalf of VIMTA LABS LIMITED
Approved by : K. S. Muneeswaran
Signed :
Designation : Senior Manager
Date : 2015.07.03
ARS METALS PVT. LTD. Chennai, Tamil Nadu, India
RAPID ENVIRONMENTAL IMPACT ASSESSMENT
FOR
THE PROPOSED AUGMENTATION & EXPANSION OF EXISTING THERMAL POWER
PLANT AT SITHURNATHAM, SIRUPUZHALPETTAI & EGUVARAPALAYAM
VILLAGES, GUMMIDIPOONDI TALUK, THIRUVALLUR DISTRICT, TAMIL NADU
This EIA report has been prepared for the purpose of obtaining Environmental Clearance from MoEF-CC, New Delhi in line with the ToR issued by MoEF-CC vide
letter no. F. No. J-13012/7/2010-IA.II (T) dt. 18.09.2014.
This report has been prepared by ‘Vimta Labs Limited’ with all reasonable skill, care and diligence within the terms of the contract with the client, incorporating our General Terms and Conditions of Business and taking account of the
resources devoted to it by agreement with the client.
PREFACE
Rapid Environmental Impact Assessment for the proposed augmentation & expansion of existing thermal power plant at Gummidipoondi, Thiruvallur
district, Tamilnadu
Table of contents
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TABLE OF CONTENTS
_______________________________________________________________ Chapter # Title Page # _______________________________________________________________ Preface i
Table of Contents iii List of Annexures viii
List of Figures ix List of Tables x 1.0 Introduction 1 1.1 Purpose of the report 1 1.2 Identification of the project & project proponent 2 1.3 Brief description of the project 3 1.3.1 Project objective 3 1.3.2 Nature and size of the project 3 1.3.3 Location of the project 5 1.4 Scope of the study 11 1.4.1 Study area for EIA 11 1.5 Methodology of the study 12 2.0 Project description 15 2.1 Type of Project 15 2.2 Need for the project 15 2.3 Project location & layout 16 2.4 Size or magnitude of operation 16 2.4.1 Land requirement 19 2.4.2 Fuel requirement, source, quality &transportation 19 2.4.3 Power evacuation 20 2.4.4 Man power requirement 20 2.4.5 Water requirement 21 2.4.6 Infrastructure 23 2.4.7 Infrastructure for labour 24 2.5 Project schedule for implementation 24 2.6 Technology and process description 24 2.6.1 Plant layout 24 2.6.2 Mechanical equipment and systems 25 2.7 Plant water system 35 2.8 Coal handling system 40
2.9 Ash handling system 42 2.10 Miscellaneous auxiliaries 51 2.10.1 Cranes, hoists & elevators 51 2.10.2 Associated facilities 52 2.10.3 General stores 52
Rapid Environmental Impact Assessment for the proposed augmentation & expansion of existing thermal power plant at Gummidipoondi, Thiruvallur
district, Tamilnadu
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TABLE OF CONTENTS (Contd..)
_______________________________________________________________ Chapter # Title Page # _______________________________________________________________
2.11 Sources of pollution and mitigation measures 53
2.11.1 Air pollution source and mitigation measures 53 2.11.2 Wastewater generation and mitigation measures 55 2.11.3 Solid waste generation and mitigation measures 56 2.11.4 Noise pollution and mitigation measures 57 2.12 Environmental laboratory 58 3.0 Description of the environment 59 3.1 Introduction 59 3.2 Methodology 59 3.3 Geology & hydrogeology 60 3.3.1 Administrative details 60 3.3.2 Basin and sub-basin 60 3.3.3 Drainage 60 3.3.4 Rainfall and climate 60 3.3.5 Geomorphology and soil types 61 3.3.6 Soil 61 3.3.7 Ground water scenario 61 3.4 Land use studies 66 3.4.1 Objectives 66 3.4.2 Methodology 66 3.4.3 Land use pattern based on satellite imagery 66 3.5 Meteorology 73 3.5.1 Methodology 73 3.5.2 Synthesis of data on climatic conditions 74 3.6 Air quality 82 3.6.1 Methodology adopted for air quality survey 82 3.6.2 Instruments used for sampling 85 3.6.3 Instruments used for analysis 85 3.6.4 Sampling and analytical techniques 85 3.6.5 Presentation of primary data 86 3.6.6 Observations of primary data 87 3.7 Noise level survey 88 3.7.1 Identification of sampling locations 88 3.7.2 Method of monitoring 88 3.7.3 Instrument used for monitoring 89 3.7.4 Parameters measured during monitoring 89 3.7.5 Presentation of results 91 3.8 Soil characteristics 92 3.8.1 Data generation 92 3.8.2 Baseline soil status 95 3.9 Water quality 97 3.9.1 Methodology 97 3.9.2 Water sampling locations 97 3.9.3 Presentation of results 98
Rapid Environmental Impact Assessment for the proposed augmentation & expansion of existing thermal power plant at Gummidipoondi, Thiruvallur
district, Tamilnadu
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TABLE OF CONTENTS (Contd..) _______________________________________________________________ Chapter # Title Page # _______________________________________________________________
3.10 Ecology and biodiversity 102
3.10.1 Introduction 102 3.10.2 Objectives of the study 102 3.10.3 Methodology 103 3.10.4 General ecology of the study area 105 3.10.5 Forest blocks 105 3.10.6 Terrestrial biodiversity 105 3.10.7 Fauna of the core zone 106 3.10.8 Flora of the buffer zone 106 3.10.9 Fauna of the buffer zone 107 3.10.10Aquatic ecosystems 109 3.10.11Conclusions 111 3.11 Demography and socio-economics 3.11.1 Methodology adopted for the study 111 3.11.2 Review of demographic and socio-economic 2001 111 3.11.3 Demography 112 3.11.4 Social structure 112 3.11.5 Literacy levels 113 3.11.6 Occupational structure 113 4.0 Anticipated environmental impacts & mitigation measures 115
4.1 Introduction 115 4.2 Impacts during construction phase 115 4.2.1 Impact on land use 115 4.2.2 Impact on soil 116 4.2.3 Impact on topography 116 4.2.4 Impact on air quality 116 4.2.5 Impact on water quality 117 4.2.6 Impact on noise levels 117 4.2.7 Impact on terrestrial ecology 117 4.3 Impacts during operational phase 118 4.3.1 Topography 118 4.3.2 Impact on air quality – point sources 118 4.3.3 Impact on air quality - fugitive emissions 127 4.3.4 Impact on water resources and water quality 127 4.3.5 Impact on land use 129 4.3.6 Impact on soil 129 4.3.7 Impact of solid wastes 130 4.3.8 Impacts on ecology 131 4.3.9 Impacts on noise levels 131 4.3.10 Predictions of impacts on socio economics 134
4.3.11 Impacts on public health and safety 134
Rapid Environmental Impact Assessment for the proposed augmentation & expansion of existing thermal power plant at Gummidipoondi, Thiruvallur
district, Tamilnadu
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TABLE OF CONTENTS (Contd..) _______________________________________________________________ Chapter # Title Page # _______________________________________________________________
4.4 Environment management plan during erection phase 134
4.4.1 Land environment management 134 4.4.2 Air quality management 135 4.4.3 Water quality management 135 4.4.4 Noise level management 135 4.4.5 Ecological management 135 4.5 Environment management plan during operation phase 135 4.5.1 Air pollution management 136 4.5.2 Water pollution management 136 4.5.3 Rainwater harvesting system 137 4.5.4 Noise pollution management 137 4.5.5 Solid waste management 137 4.6 Greenbelt development 140 4.6.1 Species for plantation 140 4.7 Cost provision for environmental measures 141 4.8 Corporate social responsibility 142 5.0 Analysis of Alternatives 145
5.1 Analysis of alternative sites for location of power plant 145 5.2 Analysis of Alternative for Unit Size Selection 145
6.0 Environmental monitoring programme 147
6.1 Introduction 147 6.2 Implementation schedule of EMP 147
6.3 Environmental monitoring and reporting procedure 147 6.4 Monitoring schedule 148 6.5 Monitoring methods and data analysis of 152
environmental monitoring 6.6 Report schedules of the monitoring data 153
6.7 Infrastructure for monitoring of environmental 154 protection measures
7.0 Additional studies 155 7.1 Public consultation 155 7.2 Risk assessment 155 7.3 Hazard identification 156 7.4 Hazard assessment and evaluation 157 7.5 Disaster management plan 169 7.6 Off-site Emergency Preparedness Plan 179
7.7 Occupational Health and Safety 183
Rapid Environmental Impact Assessment for the proposed augmentation & expansion of existing thermal power plant at Gummidipoondi, Thiruvallur
district, Tamilnadu
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7.8 Public Consultation 187
TABLE OF CONTENTS (Contd..) _______________________________________________________________ Chapter # Title Page # _______________________________________________________________
8.0 Project benefits 189 8.1 Introduction 189
8.1.1 Availability of Quality Power 189 8.1.2 Improvements in the Physical Infrastructure 189 8.1.3 Improvement in the Social Infrastructure 189 8.1.4 Employment Potential 190
9.0 Administrative aspects of environment management plan 191
9.1 Institutional Arrangements for Environment 191 Protection and Conservation
10.0 Summary & conclusion 193
10.1 Identification of project and project proponent 193 10.2 Details of the proposed project 195 10.3 Baseline environmental status 197 10.4 Anticipated environmental impacts 200 10.5 Environmental management plan 203
10.6 Post Project Environment Monitoring Programme 206 10.7 Risk Assessment and Disaster Management Plan 206 10.8 Project benefits 207 10.9 Conclusion 207 11.0 Disclosure of consultant 209 11.1 Introduction 209 11.2 The quality policy 209
11.3 Milestones and accreditations 209 11.4 Management and board of directors 210 11.5 Services offered 211 11.6 Services 211
11.7 Facilities 212 11.8 Quality systems 213 11.9 Achievements 213
QCI/NABET accreditation certificate of consultant 214
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district, Tamilnadu
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LIST OF ANNEXURES
_______________________________________________________________ Annexure # Title _______________________________________________________________
Annexure – 1 TORs issued by MoEF Annexure – 2 Compliance report for ToR issued by MoEF Annexure – 3 EC & CTO for the Existing Plant Annexure – 4 MoEF certified EC compliance Annexure – 5 Administrative setupmaps Annexure – 6 Applicable Environmental Standards Annexure – 7 Methodology adopted for sampling and analysis Annexure – 8 Study area map Annexure – 9 Ambient Air Quality Results of study area Annexure – 10 Demographic details of the study area Annexure – 11 Land use details of the study area Annexure – 12 Drainage pattern & water bodies Annexure – 13 Plant & site photos Annexure – 14 CGWA Letter for Ground water uptake letter Annexure – 15 Lab Report On Coal Characteristics Annexure – 16 MoEF Questionnaires for Environmental Appraisal of Thermal Power Plant Annexure – 17 Public Hearing - Advertisement copy Annexure – 18 English Executive Summary Annexure – 18B Tamil Executive Summary Annexure – 19 Public Hearing - Minutes of the Meeting Annexure – 20 MoU for coal supply Annexure – 21 Agreement for selling Fly ash
Rapid Environmental Impact Assessment for the proposed augmentation & expansion of existing thermal power plant at Gummidipoondi, Thiruvallur
district, Tamilnadu
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LIST OF FIGURES
_______________________________________________________________ Figure# Title Page# _______________________________________________________________
1.1 Index map of the plant site 6 1.2 10 km study area map 7 1.3 Topographic map 8 1.4 Aerial view of the plant site 9 2.1 Plant layout 17 2.2 Water balance (upon expansion) 22 2.3 Power generation flow scheme 26
3.1 Hydrogeology of Thiruvallur district 65 3.2 Flow chart showing methodology of land use mapping 68 3.3 Satellite imagery of the study area 70 3.4 Landuse of the study area 72 3.5(A) Windrose for pre monsoon & monsoon season- IMD, Chennai 77
3.5(B) Windrose for post monsoon & winter season – IMD, Chennai 78 3.5(C) Annual wind rose - IMD, Chennai 79 3.6 Site specific wind rose (May – July 2014) 81 3.7 Air quality sampling locations 83 3.8 Noise monitoring locations 90 3.9 Soil sampling locations 94 3.10 Water sampling locations 99 3.11 Ecological sampling locations 104 4.1 Short term 24 hourly incremental GLCs of PM 124 4.2 Short term 24 hourly incremental GLCs of SO2 125 4.3 Short term 24 hourly incremental GLCs of NOX 126 4.4 Predicted noise dispersion contours 133 7.1 Damage Contour For Two LDO Tanks (150 Kl Each) On Fire 164 7.2 Damage Contour For Two HFO Tanks (300 Kl Each) On Fire 165
7.3 On-Site Emergency Organization Chart 178 7.4 Public Hearing Photos 188
9.1 Organizational structure of environment cell 192 10.1 10 Km Radius Study Area Of The Project Site 194
Rapid Environmental Impact Assessment for the proposed augmentation & expansion of existing thermal power plant at Gummidipoondi, Thiruvallur
district, Tamilnadu
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LIST OF TABLES
_______________________________________________________________ Table# Title Page# _______________________________________________________________
1.1 Project brief 3 1.2 Environmental setting of the plant 10 1.3 Environmental attributes and frequency of monitoring 13 2.1 Demand projections 15 2.2 Salient features of thermal power plant 18 2.3 Land break-up 19 2.4 Coal consumption 20 2.5 Indonesian coal characteristics 20 2.6 Man power demand 20 2.7 Water demand 21 2.8 Steam generator specifications 31 2.9 Turbine specifications 33 2.10 Sources of wastewater and its management 38 2.11 Details of coal handling system 41 2.12 Stack monitoring data 54 2.13 Wastewater generation from the power plant 56 2.14 Solid waste generation and disposal 57 2.15 Noise level exposure limits 57 3.1 Ground water resources 63 3.2 Sensitivity of meteorology monitoring equipment 73 3.3 Climatological data-IMD, Chennai 76 3.4 Seasonal frequencies of cyclones in east coast of India 76 3.5 Summary of wind pattern – IMD, Chennai 76 3.6 Summary of the meteorological data at site 80 3.7 Details of ambient air quality monitoring locations 82 3.8 Monitored parameters and frequency of sampling 84 3.9 Instruments used for analysis of samples 85 3.10 Techniques used for ambient air quality monitoring 85 3.11 Summary of ambient air quality results 86 3.12 Details of noise monitoring locations 89 3.13 Noise levels in the study area 91 3.14 Analytical techniques for soil analysis 92 3.15 Details of soil sampling locations 93 3.16 Soil analysis results 95 3.17 Standard soil classification 96 3.18 Details of water sampling locations 98 3.19 Ground water quality 100 3.20 Surface water quality 101 3.21 List of ecological sampling locations 103 3.22 List of forest blocks within 10 Km radius 105 3.23 List of flora in the core area 106 3.24 List of fauna in the core area 106 3.25 List of flora from the buffer zone 107
Rapid Environmental Impact Assessment for the proposed augmentation & expansion of existing thermal power plant at Gummidipoondi, Thiruvallur
district, Tamilnadu
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3.26 List of fauna from the buffer zone 108 3.27 List of plankton recorded during study period 110 3.28 Aquatic fauna from study area 110 3.29 Distribution of population 112 3.30 Distribution of population by social structure 113 3.31 Distribution of literate and literacy rate 113 3.32 Occupational structure 114 4.1 Hourly mean meteorological data 121 4.2 Stack details 122 4.3 Predicted 24-hourly incremental concentrations 122 4.4 Resultant concentrations due to incremental GLC’s 122 4.5 Types of wastewater generation and treatment details 128 4.6 Expected quality of wastewater 129 4.7 Expected solid waste from power plant 130 4.8 Major noise generating sources 132 4.9 Selected areas of fly ash utilization 138 4.10 Cost provision for environmental measures 141 4.11(a)Expenses towards CSR 142 4.12(b)Expenses towards CSR 143 6.1 EMP implementation schedule 147 6.2 Environmental monitoring schedule during construction stage 148 6.3 Environmental monitoring schedule during operation phase 150
7.1 Hazardous materials proposed to be stored/transported 156
7.2 Category wise schedule of storage tanks 156 7.3 Properties of fuels used in the plant 157
7.4 Applicability of GOI rules to fuel/chemical storage 157 7.5 Preliminary hazard analysis for storage areas 158
7.6 Preliminary hazard analysis for the whole plant in general 158 7.7 Fire explosion and toxicity index 159 7.8 Fire explosion and toxicity index 159 7.9 Damage due to the incident radiation intensities 161 7.10 Radiation exposure and lethality 161 7.11 Scenarios considered for MCA Analysis 162 7.12 Properties of fuels considered for modeling 162 7.13 Occurrence of various intensities – Pool fire 162 7.14 Hazard analysis for process in power plant 167 7.15 Hazardous events contributing to risk at on-site facility 168 7.16 Off-site action plan 182
10.1 Environmental setting of the plant 193 10.2 Salient Features of the Proposed Project 195 10.3 Summary of Ambient Air Quality in the Study Area 197 10.4 Resultant Concentrations Due to Incremental GLCs 201 10.5 Expected Solid Waste from Power Plant 202 Details of Personnel Involved In Current EIA Report 214
Rapid Environmental Impact Assessment for the proposed augmentation &
expansion of existing thermal power plant at Gummidipoondi, Thiruvallur
district, Tamilnadu
Chapter – 1
Introduction
VIMTA Labs Limited, Hyderabad/Coimbatore 1
1.0 INTRODUCTION
M/s. ARS Metals Private Limited (hereinafter referred to as ARS) proposes for
an augmentation & expansion of its existing thermal power plant (TPP) at
Sithurnatham, Sirupuzhalpettai & Eguvarapalayam villages of Gummidipoondi taluk,
Thiruvallur district, Tamil Nadu. The existing plant operates in a total plant area of
25.49 ha (62.99 acres) for which EC has been obtained vide Letter No. J-
13012/7/2010-IA.II (T) dated 20th May, 2011 for 2 x 60 MW. Of this, only 1 x 60
MW is under operation since commencing the power plant. The proposed expansion
activity involves augmentation of the other 60 MW to 135 MW and erection of
additional 350 MW Super Critical TPP. For the current expansion, additional 11.49 ha
(28.39 acres) of land, adjacent (NE) to existing plant site has been acquired.
Altogether, the plant after expansion will be operated in 36.98 ha (91.38 acres). The
total cost for the proposed expansion will be INR 2,400/- Crores.
The purpose of proposed expansion is to meet its group captive requirement and
the excess power will be sold to Tamil Nadu state grid.
This chapter describes the purpose of the report, identification of the current
expansion activity and the project proponent, brief description of nature, size and
location of the project and importance to the region and country. This chapter also
describes the scope of the study and details of regulatory scoping carried out as per
Terms of Reference (ToR) issued by Ministry of Environment and Forests (MoEF),
New Delhi.
1.1 Purpose of the report
In order to obtain Environmental Clearance from MoEF and Consent for
Establishment (CFE) from the Tamilnadu Pollution Control Board (TNPCB) for the
current expansion activities, Environmental Impact Assessment (EIA) report with
detailed Environmental Management Plan (EMP) is essential as per the EIA
notification and its subsequent amendments.
As per the EIA Notification dated 14th September 2006, the proposed activity falls
under schedule. no. 1 (d) [Thermal Power Plant > 500 MW] and categorized under
category ‘A’.
The project was presented in the 18th meeting of the reconstituted expert appraisal
committee (EAC) – MoEF [Thermal Power] held on 1st August 2014 for ToR approval
and received ToR vide letter no. F. No. J-13012/7/2010-IA.II (T) dt. 18.09.2014
(Annexure – 1).
The objective of this REIA is to foresee the potential environmental problems that
would crop up out of the proposed expansion activity and address them in the
project planning and design stage.
Rapid Environmental Impact Assessment for the proposed augmentation &
expansion of existing thermal power plant at Gummidipoondi, Thiruvallur
district, Tamilnadu
Chapter – 1
Introduction
VIMTA Labs Limited, Hyderabad/Coimbatore 2
The specific objectives of this REIA are as follows:
To review the current environmental status of the plant under operation,
and its surrounding area, to estimate the pollution that would occur after
commissioning the proposed expansion activity, and its impact on the
surrounding environment.
To suggest an EMP including pollution control methods, to ensure that the
pollution will be well within the limits as prescribed by CPCB and TNPCB and
minimize the adverse environmental impacts of the development, so that
the quality of environment is not only preserved but also enhanced.
To propose a Post Project Monitoring Plan (PPMP) to ensure that the EMP
achieves its desired objectives.
1.2 Identification of Project & Project Proponent
The proposed augmentation / expansion of the existing thermal power plant is
identified and justified based on the growing demand of power requirement.
India's Electricity Act 2003 introduced structural changes to the power industry,
permitting private investment for the first time since 1948. This allowed power
producers to sell power directly to industrial consumers under the Group Captive
model. ARS has been a pioneer in developing the Group Captive model which
allows the flexibility to choose between two market routes.
ARS Metals Pvt. Ltd.
ARS is a pioneer in the field of manufacturing TMT re-bars (Thermo Mechanically
Treated) and Mild Steel Billets. ARS metals being one of the largest integrated
steel plants in Southern India, has acquired high reverence from its loyal
customers throughout South India.
ARS has a unique distribution network in South India. The company has made it
easy for the customers to procure their requirements such as high quality TMT re-
bars and mild steel billets at their location through authorized distributors at
various places in the South India.
Company Highlights
One of the largest integrated Steel Plants in Southern India.
Fully modern & automated plant for best quality TMT re-bars and Mild Steel
Billets.
Excellent distribution Network spread across entire Southern India.
Sophisticated infrastructure facilities for R&D.
Stringent Quality Control standards to ensure the best quality TMT re-bars
and Mild Steel Billets.
Rapid Environmental Impact Assessment for the proposed augmentation &
expansion of existing thermal power plant at Gummidipoondi, Thiruvallur
district, Tamilnadu
Chapter – 1
Introduction
VIMTA Labs Limited, Hyderabad/Coimbatore 3
1.3 Brief Description of the Project
1.3.1 Project Objective
The proposed expansion involves augmentation of 60 MW to 135 MW Group Captive
Power Plant (GCPP) and erection of additional 350 MW Independent Power Plant
(IPP) in addition to the existing 1 x 60 MW (GCPP) under operation.
1.3.2 Nature and Size of the Project
The existing plant operates in a total plant area of 25.49 ha (62.99 acres) for
which EC has been obtained vide Letter No. J-13012/7/2010-IA.II (T) dated 20th
May, 2011 for 2 x 60 MW. Of this, only 1 x 60 MW is under operation since
commencing the power plant. The proposed expansion activity involves
augmentation of the other 60 MW to 135 MW and erection of additional 350 MW
TPP. For the current expansion, additional 11.49 ha (28.39 acres) of land,
adjacent (NE) to existing plant site has been acquired. Altogether, the plant after
expansion will be operated in 36.98 ha (91.38 acres). The total cost for the
proposed expansion will be INR 2,400/- Crores. The details of the project are given
in Table-1.1.
TABLE – 1.1
PROJECT BRIEF
Sr. No. Description Details
1 Name of the project Augmentation & expansion of existing thermal power plant
2 Registered address of the proponent
Rajesh Bhatia Director M/s. ARS Metals Private Limited
D-109, 2nd Floor, LBR complex, Anna Nagar (East), Chennai – 600 102
3 Telephone numbers Ph. No. 044-43500687
4 Location of the plant site Sithurnatham, Sirupuzhalpettai & Eguvarpalayam villages, Gummidipoondi taluk & Thiruvallur district, Tamil Nadu
5 Power generation capacity
Status Capacity
Existing (as per EC) 2 x 60 MW (120 MW)
Upon expansion
1 x 60 MW 1 x 135 MW 1 x 350 MW [Super critical]
Total 545 MW _
6 Power requirement The entire power demand will be met from the existing & proposed captive power plant
7 Fuel requirement
Fuel Existing After expansion
Coal (TPD) 1000 (0.3 MTPA) 7712 (2.31 MTPA)
Rapid Environmental Impact Assessment for the proposed augmentation &
expansion of existing thermal power plant at Gummidipoondi, Thiruvallur
district, Tamilnadu
Chapter – 1
Introduction
VIMTA Labs Limited, Hyderabad/Coimbatore 4
8 Water Requirement Total water demand: 240 KLD Fresh water requirement: 79.84 KLD
Source: Existing bore wells
9 Details of Land use/Land Cover within plant site
Total plant area after expansion – 36.98 ha (91.38 acres)
Sr. No. Description Area
ha acres %
1 Boiler house 1.07 2.64 2.89
2 Turbine generator hall 0.88 2.17 2.38
3 Air cooled condenser 1.57 1.41 4.25
4 Water treatment plant 0.41 1.01 1.11
5 ESP and stack 0.56 1.38 1.51
6 Switch yard 2.59 6.40 7.00
7 Coal storage yard 2.18 5.38 5.90
8 Greenbelt 13.30 32.87 35.96
9 Raw water reservoir 3.12 7.71 8.44
10 Road 5.59 13.81 15.12
11 Ash dyke 3.25 8.03 8.79
12 Open area 2.46 6.08 6.65
Total 36.98 91.38 100
_ 10 Total investment of the
project/activity
The total cost for the proposed expansion
is INR 2400/- Crores
11 Funds allocated for EMP Capital cost: INR. 360 Crores Recurring cost: INR. 26 Crores/annum
12 Estimated Employment Present employees – 150 nos. Additional employees – 200 nos.
13 Name of the Environment Consultant involved in EIA report preparation
M/s. VIMTA LABS LIMITED S. No. in QCI list: #159
Branch office:
No. 8 – Azad Road R. S. Puram, Coimbatore - 641002
Regd. office: 142, IDA, Phase-II, Cherlapally, Hyderabad-500 051
QCI/NABET Accredited EIA Consultancy Organization, NABL Accredited, ISO 17025
Certified and MoEF Recognized Laboratory
Rapid Environmental Impact Assessment for the proposed augmentation &
expansion of existing thermal power plant at Gummidipoondi, Thiruvallur
district, Tamilnadu
Chapter – 1
Introduction
VIMTA Labs Limited, Hyderabad/Coimbatore 5
1.3.3 Location of the Project
The plant site falls within 13° 21’ 46.818” »» 13° 25’ 49.772” North latitude and
80° 0’ 7.77” and 80° 4’ 12.038” longitude. The entire plant area falls in the Survey
of India topo sheet nos. 57 O/15, 66 C/2 & 66 C/3. Existing plant site is 4.8 km,
West of National Highway – 5. The nearest railway station is Gummidipoondi R.S.,
which is at a distance of about 6.1 km, ESE. The nearest airport is Anna
International Airport, Chennai which is located at a distance of 48.3 km, SSE from
plant site. The project site falls in Sithurnatham, Sirupuzhalpettai &
Eguvarpalayam villages, Gummidipoondi taluk, Thiruvallur district, Tamilnadu.
List of S.F. Nos. covered under the project area are given below.
Existing land area: 25.49 ha (62.99 acres)
52/3 52/4 207/1 pt 206/2 44/2 207/13 209/7 651/1 611/1G
52/6 52/2 207/10 207/2 44/3 207/14 209/8 651/2 611/1I
52/7 52/8 207/11 207/4 50/3A 207/17 53/4 651/3
52/9 52/1B 207/12 46/2 51/12 207/18 53/6 651/4
53/12 49/3 207/16 49/8 51/3 207/15 53/10 611/1A
53/13 49/5 45/4 50/2C 51/6 207/19 53/11 611/1B
50/4 50/5C 49/1 50/2E 52/1A 209/1 53/7 611/1C
50/5B 50/2B 49/2 50/2A 207/3 209/2 53/5 611/1D
50/6B 50/2D 49/4 50/3C 207/5 209/3 53/8 611/1F
52/5 50/5D 49/6 50/3D 207/7 209/4 53/9 611/1H
45/3 50/6A 49/7 50/3E 207/8 209/5 611/1K 611/1J
46/1 50/5A 207/1 pt 50/3B 207/9 209/6 650 611/1E
Proposed additional land area : 11.49 ha (28.39 acres)
210/1L 210/1K 63/12 A 210/1H 119/18C 119/6F 131/14
210/1A 210/1M 609/1 210/1I 131/17 131/11A 129/9B
609/3 210/2 609/6A 210/1J 107/7 126/7 129/1
610/2C 609/5C 612/1A 126/2C 126/6A 126/2A 129/2
63/3 609/2 63/11 117/8B 117/8C 126/2B 129/10A
210/1B 609/4 63/3 120/15B 120/14 131/20 129/11
210/1C 609/6B 63/5A 131/9 131/7 131/15 29/10B
210/1D 610/2B 63/5B 134/5C 131/10C 128/5 129/1
210/1F 610/1A 210/1B 128/3 128/4 120/5
210/1G 609/5A 210/1E 125/2C 125/2B 118/8A
The environmental setting of the plant is given in Table-1.2. The location map of
the project site is shown in Figure-1.1 and the topographic map (5.0 km) showing
site co-ordinates is shown is Figure-1.3. Aerial view of the project site showing the
existing plant site and the proposed area allotted for the erection of 350 MW (IPP) is
shown in Figure-1.4.
Rapid Environmental Impact Assessment for the proposed augmentation &
expansion of existing thermal power plant at Gummidipoondi, Thiruvallur
district, Tamilnadu
Chapter – 1
Introduction
VIMTA Labs Limited, Hyderabad/Coimbatore 6
FIGURE – 1.1
INDEX MAP OF THE PLANT SITE
EXISTING PLANT SITE
Rapid Environmental Impact Assessment for the proposed augmentation &
expansion of existing thermal power plant at Gummidipoondi, Thiruvallur
district, Tamilnadu
Chapter – 1
Introduction
VIMTA Labs Limited, Hyderabad/Coimbatore 7
FIGURE – 1.2
10 KM STUDY AREA MAP
Rapid Environmental Impact Assessment for the proposed augmentation & expansion of existing thermal power plant at Gummidipoondi, Thiruvallur District, Tamilnadu
Chapter – 1
Introduction
VIMTA Labs Limited, Hyderabad/Coimbatore 8
FIGURE – 1.3
TOPOGRAPHIC MAP
ARS Metals Private Limited TOPO Map showing the project site
and its co-ordinates
Rapid Environmental Impact Assessment for the proposed augmentation & expansion of existing thermal power plant at Gummidipoondi, Thiruvallur District, Tamilnadu
Chapter – 1
Introduction
VIMTA Labs Limited, Hyderabad/Coimbatore 9
FIGURE – 1.4
AERIAL VIEW OF THE PLANT SITE
EXISTING PLANT
POWER PLANT
AREA FOR
PROPOSED
EXPANSION
EXISTING PLANT
Rapid Environmental Impact Assessment for the proposed augmentation &
expansion of existing thermal power plant at Gummidipoondi, Thiruvallur
District, Tamilnadu
Chapter – 1
Introduction
VIMTA Labs Limited, Hyderabad/Coimbatore 10
TABLE – 1.2
ENVIRONMENTAL SETTING OF THE PLANT
Sr. No. Particulars Details
1 Site-coordinates Refer Figure-1.3
2 Elevation 18.0 m AMSL
3 Climatic conditions (IMD, Chennai)
a. Annual Max. Temp: 43.4 0C b. Annual Min. Temp: 16.0 0C c. Annual Total Rainfall: 1214.6 mm
d. Predominant Wind Direction: Pre-monsoon: S, SSW Monsoon: SSW, SW, S
Post monsoon: NNE, E, N, NE Winter: NE, S, NNE, E Annual: SSW, S, SW
4 Climatic conditions (Plant site) 1st May to 31st July 2014 a. Max. Temp: 43.04 0C b. Min. Temp: 22.0 0C
c. Rainfall: 275.6 mm d. Predominant Wind Direction:
First pre-dominant: West 18.49% Second pre-dominant: South 14.56% Third pre-dominant: WSW 11.94% Calm: 3.34%
5 Land use Industrial
6 Nearest highway NH-5 – 4.8 km, East
7 Nearest railway station Gummidipoondi R.S. – 6.1 km, ESE
8 Nearest airport Anna International Airport, Chennai – 48.3km, SSE
9 Nearest habitations Chitoornatham – 0.5 km, West
Eguvarpalayam – 1.7 km, NNW
10 Densely populated area Chennai city – 44.7 km, SSE
11 Inland water bodies Chittoornatham pond – 1.0 km, West Pulicat lake – 8.1 km, NE Arani river – 7.4 km, SSE
Pallavada lake – 6.6 km, NW
12 Ecologically sensitive zones like
Wild Life Sanctuaries, National Parks and biospheres
Nil
13 Defense establishments None within 10 km radius
14 Socio-economic factors No Resettlement and Rehabilitation issues
15 Seismicity zone Zone – III as per IS: 1893 (Part-1) 2002
16 Nearest sea coast Bay of Bengal –26.7 km, East
17 Reserve forests Puliyur forest – 3.1 km, SSW Periyapuliyur forest – 4.3 km, SW Pallavakam R.F. – 5.6 km WSW Thervoy R.F. – 5.7 km, SW Manali R.F. – 5.7 km, SSW
Siruvada forest – 8.2 km, WSW Palem forest – 12.3 km, WNW
18 Historical / archaeological places
Nil within 15.0 km from project boundary
WRPLOT View - Lakes Environmental Software
WIND ROSE PLOT:
Station # 03
COMMENTS: COMPANY NAME:
MODELER:
DATE:
8/25/2014
PROJECT NO.:
NORTH
SOUTH
WEST EAST
4%
8%
12%
16%
20%
WIND SPEED (m/s)
>= 11.1
8.8 - 11.1
5.7 - 8.8
3.6 - 5.7
2.1 - 3.6
0.5 - 2.1
Calms: 3.34%
TOTAL COUNT:
719 hrs.
CALM WINDS:
3.34%
DATA PERIOD:
Start Date: 1/1/2014 - 00:00End Date: 1/30/2014 - 23:00
AVG. WIND SPEED:
3.57 m/s
DISPLAY:
Wind SpeedDirection (blowing from)
Rapid Environmental Impact Assessment for the proposed augmentation &
expansion of existing thermal power plant at Gummidipoondi, Thiruvallur
District, Tamilnadu
Chapter – 1
Introduction
VIMTA Labs Limited, Hyderabad/Coimbatore 11
1.4 Scope of the Study
With a view to assess the environmental impacts due to the proposed expansion
activity ARS availed the services of M/s. Vimta Labs Ltd, Hyderabad / Coimbatore to
prepare EIA Report for various environmental attributes including air, noise, water,
land and ecology along with parameters of human interest which may be affected
and to prepare an EMP for mitigating adverse impacts.
This EIA report has been compiled incorporating one season based baseline
environmental quality data as per the guidelines and requirements of MoEF, Central
Pollution Control Board (CPCB) and Tamil Nadu Pollution Control Board (TNPCB).
Environmental baseline monitoring has been carried out during non-monsoon
season (1st May to 31st July 2014) and used to identify potential impacts. Modeling
exercises have been carried out to predict and evaluate impacts. An Environment
Management Plan is also delineated.
1.4.1 Study Area for EIA
The study area for EIA study comprises of 10 km radius area around the periphery
of existing plant site and the proposed area allotted for the expansion activities. The
study area map is shown in Figure-1.2.
The scope of the study broadly includes:
Field sampling of environmental attributes at various representative locations
in the study area to establish the baseline environmental status;
Collate and compile secondary data including socio-economic data from
published literature / government publications;
Estimate pollution loads that would be generated by the proposed project;
Predict incremental levels of pollutants in the study area due to the proposed
project;
Evaluate the predicted impacts on the various environmental attributes by
using scientifically developed and widely accepted Environmental Impact
Assessment Modeling Methodologies;
Prepare an Environment Management Plan (EMP) to mitigate the predicted
impacts; and
Identify critical environmental attributes required to be monitored during the
project execution and to suggest post project monitoring.
Rapid Environmental Impact Assessment for the proposed augmentation &
expansion of existing thermal power plant at Gummidipoondi, Thiruvallur
District, Tamilnadu
Chapter – 1
Introduction
VIMTA Labs Limited, Hyderabad/Coimbatore 12
1.5 Methodology of the Study
Reconnaissance survey was conducted by M/s. Vimta Labs Limited, Hyderabad
and officials of ARS and sampling locations were identified on the basis of:
Predominant wind directions expected during the period of baseline monitoring
in the study area and also recorded by Indian Meteorological Department (IMD)
Topography and location of surface water bodies like ponds, canals and rivers;
Location of villages / towns / sensitive areas;
Identified pollution pockets, if any within the study area;
Accessibility, power availability and security of monitoring equipment;
Areas which represent baseline conditions; and
Collection, collation and analysis of baseline data for various environmental
attributes.
The monitored environmental attributes and frequency of monitoring are
presented in Table – 1.3.
Rapid Environmental Impact Assessment for the proposed augmentation &
expansion of existing thermal power plant at Gummidipoondi, Thiruvallur
District, Tamilnadu
Chapter – 1
Introduction
VIMTA Labs Limited, Hyderabad/Coimbatore 13
TABLE – 1.3
ENVIRONMENTAL ATTRIBUTES AND FREQUENCY OF MONITORING
Sr. No. Attributes Parameters Frequency
1 Ambient air quality PM10, PM2.5, SO2 and NOX, CO, Pb, As, Ni, C6H6, B(a)P, O3, NH3 & Hg
Two consecutive days per week at 8 locations
2 Meteorology Wind speed, Direction, temperature, Relative
humidity, Rainfall, cloud cover and atmospheric pressure
One hourly recording of wind speed, wind direction, cloud
cover, temperature (13-weeks) at 1 location
3 Water quality Physical, Chemical and Bacteriological
parameters. As per IS:10500 (2012)
Grab samples were collected from nine (6 GW + 2 SW)
locations once during the study period
4 Ecology Existing terrestrial and aquatic flora and fauna in the study area
Through field studies once during the study period and based on the review of secondary data
5 Noise levels Noise levels in dB (A) Once during study period at ten locations
6 Soil characteristics Parameters related to agricultural and
afforestation potential
At eight locations once during the study period
7 Land use Establishing land use pattern
Based on the land use data published in District Census Handbook, 2001 & based on Satellite Imagery
8 Socio-economic aspects
Socio-economic and work force characteristics and other demographic aspects
Based on published statistics of 2001 Census
9 Geology Geological history Geological data based on
data collected from secondary sources & based on Satellite Imagery
10 Hydrology (surface & ground)
Drainage area and pattern, nature of
streams, aquifer
characteristics, recharge and discharge areas
Based on data collected from secondary sources
11 Risk assessment, disaster management plan
and occupational health & safety
Identify areas where disaster can occur and identify areas of
occupational hazards
Based on pool fire modeling and risk assessment studies
Rapid Environmental Impact Assessment for the proposed augmentation
& expansion of existing thermal power plant at Gummidipoondi,
Thiruvallur District, Tamilnadu
Chapter – 2
Project Description
VIMTA Labs Limited, Hyderabad/Coimbatore 15
2.0 PROJECT DESCRIPTION
This chapter addresses the details of the proposed augmentation & expansion of
thermal power plant (TPP) in context with the basic raw material requirement,
processes and capacities, utilities and services, infra-structural facilities, sources
of pollution and proposed mitigation measures.
2.1 Type of Project
The proposed expansion deals with the augmentation & expansion of existing
thermal power plant. Of the existing power plants 1 x 60 MW (60 MW) is operating
and the proposed project involves augmentation of another existing 60 MW to 135
MW and erection of additional 350 MW TPP.
The existing power plant consists of a 60 MW CFBC pulverized coal fired boiler rated
to generate 235.13 tonnes of steam per hour (TPH). The current expansion involves
installation of 135 MW & 350 MW TPP with a boiler rating of 563 TPH & 950 TPH
respectively. The superheated steam pressure will be 170 kg/cm2 and temperature
will be 537 ºC with reheat temperature of 537 ºC. Coal required for the plant upon
the expansion would be 2.31 MTPA which will be sourced by sea from Indonesia to
Ennore port which is located ~50 km by road and thereon through trucks (40 T
Container) to the plant site. The total water demand will be about 240 KLD which
will be drawn from existing borewells within the plant site. Power evacuation will be
from Thervaikandigai, which is located 14.0 km from site and hence a new
transmission line will be erected.
2.2 Need for the Project
The demand projections on all India basis for the year 2011-12, 2016-17 and
2021-22 are given in Table-2.1.
TABLE-2.1
DEMAND PROJECTIONS
Year Electricity Energy Requirement at
Power Station Bus Bars (GWh) Annual Peak Electric Load at
Station Bus Bars (MW)
2011-12 968659 152746
2016-17 1392066 218209
2021-22 19145058 298253
Justification of the Project
Deficit in power supply demand
Projected power demand by the end of 12th five year plan
Ever increasing power demand
Governments focus of infrastructural development as part of industrialization
Hence, the proposed augmentation cum expansion of coal based TPP is justified.
Rapid Environmental Impact Assessment for the proposed augmentation
& expansion of existing thermal power plant at Gummidipoondi,
Thiruvallur District, Tamilnadu
Chapter – 2
Project Description
VIMTA Labs Limited, Hyderabad/Coimbatore 16
2.3 Project Location & Layout
The project site is located in Sithurnatham, Sirupuzhalpettai & Eguvarpalayam
villages, Gummidipoondi taluk, Thiruvallur district, Tamil Nadu. The map showing
the general and specific location of the plant is shown Figure-1.1, 1.2 & 1.3 of
Chapter – 1. The detail of environmental setting is also given in Table – 1.2 of
Chapter – 1.
Layout of the existing power plant has been planned considering the space
requirements for all the equipment, systems, buildings, structures, coal storage
area and marshalling yard, ash silos, raw water storage tank, water treatment
plant etc., Necessary plant drainage system has been provided at the existing
plant site and also planned for the proposed additional area for the expansion
activities. In laying out various facilities, following general aspects have been
taken into consideration:
Provision to install 1 X 350 MW TPP (Independent);
Coal storage yard for 7 days requirement;
Ash silos for fly ash storage;
Predominant wind directions as shown in the wind rose to minimise pollution,
fire risk etc.;
Raw water supply, storage facilities; and
Availability of adequate space for fabrication / construction equipment.
All facilities of the plant area will be laid out in close proximity to each other to
the extent practicable so as to minimize the land requirement. The layout
facilitates movement of men and materials between the various facilities both
during construction and operation. The layout map showing the plant site and
plant boundary is shown in Figure-2.1.
2.4 Size or Magnitude of Operation
Taking into account, reliability of equipment and matching capacities between the
different sections of the plant, the type of equipment/installation system and the
departmental capacities at the plant, have been arrived. A condensed description
of proposed utilities and major equipment is given in the following sections.
The capacity of total power plant after the proposed expansion will be 545 MW
[Existing 1 x 60 MW (Sub critical boiler); Proposed 1 x 135 MW (Sub critical
boiler) + 1 x 350 MW (Super critical boiler)]. The salient features of proposed
power plant are presented in Table-2.2.
Rapid Environmental Impact Assessment for the proposed augmentation
& expansion of existing thermal power plant at Gummidipoondi,
Thiruvallur District, Tamilnadu
Chapter – 2
Project Description
VIMTA Labs Limited, Hyderabad/Coimbatore 17
FIGURE-2.1
PLANT LAYOUT
Rapid Environmental Impact Assessment for the proposed augmentation
& expansion of existing thermal power plant at Gummidipoondi,
Thiruvallur District, Tamilnadu
Chapter – 2
Project Description
VIMTA Labs Limited, Hyderabad/Coimbatore 18
TABLE-2.2
SALIENT FEATURES OF THERMAL POWER PLANT
Sr. No. Features Description
1 Total capacity 545 MW
2 Configuration Under operation: 1 x 60 MW Proposed: 1 x 135 MW + 1 X 350 MW
3 Technology 1 X 60 MW & 1 X 135 MW PF Boiler with re-heat cycle: M.S: 170 kg/cm2
/ 537OC;
Reheat: 537OC
1 X 350 MW – Super Critical PF Boiler with re-heat cycle: M.S: 255 kg/cm2
/ 585OC; Reheat: 585OC
4 Boilers 1 x 235.13 TPH; Sub critical (Existing 1 x 60 MW)
1 x 563 TPH; Sub critical (Proposed 135 MW) 1 x 950 TPH; Super critical (Proposed 350 MW) CFBC/Pulverized Coal fired, natural circulation boilers
5 Generators Three generators with rated 60 MW, 11KV, 50 Hz, 3 ph and 0.8 PF 135 MW,
350 MW
6 Power evacuation Power evacuation will be from Thervaikandigai, which is located 14.0 km from site
7 Condenser Air cooled condenser
8 Auxiliary Cooling System
Finfan coolers for cooling of turbine, generator and boiler auxiliaries
9 HFO/LDO Storage Tanks
2 x 300 KL HFO tanks and 2 x 150 KL LDO tanks
10 Switchyard, Generator, Transformer and Station Transformer
230 KV System
11 Fuel Coal
12 Source of Coal Indonesia Coal (Imported)
13 Coal Handling Ground hoppers, stacker, reclaimers and double stream conveying system
14 Coal Requirement 2.31 MTPA at 85% PLF
15 Sulphur content 0.5%
16 Ash Content in Coal 9.0%
17
A B
Ash generation
Bottom Ash Fly Ash
0.135 MTPA
0.108 MTPA 0.027 MTPA
18 Ash Handling Dry ash collection
19 ESP efficiency 99.99%
20 Stack 145 m AGL [Common for 1 x 60 MW & 1 X 135 MW] 220 m AGL [1 x 350 MW]
21 Total water demand 240 KLD (0.098 cusec)
22 Source of water Existing borewells
23 Project cost INR. 2400 Crores
Rapid Environmental Impact Assessment for the proposed augmentation
& expansion of existing thermal power plant at Gummidipoondi,
Thiruvallur District, Tamilnadu
Chapter – 2
Project Description
VIMTA Labs Limited, Hyderabad/Coimbatore 19
2.4.1 Land Requirement
The existing plant operates in an area of 25.49 ha (62.99 acres). Additionally
11.49 ha (28.39 acres) of barren land adjacent to the existing site has been
acquired for the current expansion activities. Totally the plant upon expansion
operates in an area of 36.98 ha (91.38 acres). Out of which, an area about 26.07
ha will be used for plant facilities and 10.97 ha area will be used for greenbelt
development. The break up details of the land use is given in Table-2.3.
TABLE-2.3
LANDUSE BREAK-UP
Sr. No. Land Use
Area
Existing (ha)
Proposed (ha)
Upon Expansion
(ha) %
1 Boiler house 0.62 0.45 1.07 2.89
2 Turbine generator hall 0.38 0.50 0.88 2.38
3 Air cooled condenser 0.56 1.01 1.57 4.25
4 Water treatment plant 0.22 0.19 0.41 1.11
5 ESP and stack 0.20 0.36 0.56 1.51
6 Switch yard 2.09 0.50 2.59 7.00
7 Coal storage yard 1.60 0.58 2.18 5.90
8 Greenbelt 10.33 2.97 13.30 35.96
9 Raw water reservoir 1.22 1.90 3.12 8.44
10 Road area 4.37 1.22 5.59 15.12
11 Ash dyke 1.62 1.63 3.25 8.79
12 Open area 2.28 0.18 2.46 6.65
Total 25.49 11.49 36.98 100
2.4.2 Fuel requirement, Source, Quality & Transportation
Fuel Requirement and Source
As a coal based thermal power plant, the primary fuel of the plant will be 100%
Indonesian coal. The maximum annual coal consumption for the plant after
expansion will be about 2.31 MTPA. Coal requirement details along with its source
are presented in Table – 2.4. Coal from Indonesia would be transported through
sea to Ennore port and thereon through trucks to the existing plant site.
The coal requirement for the proposed power plant is based on
PLF : 85%
Plant heat rate : 2500 kcal/kwhr
Gross Calorific value : 4,500 kCal/kg
Secondary fuel Light Diesel Oil (LDO) will be used only for cold start and Heavy
Fuel Oil (HFO) will be used as support fuel at low loads and flame stabilization.
The required quantity will be brought to plant site via road transportation.
Rapid Environmental Impact Assessment for the proposed augmentation
& expansion of existing thermal power plant at Gummidipoondi,
Thiruvallur District, Tamilnadu
Chapter – 2
Project Description
VIMTA Labs Limited, Hyderabad/Coimbatore 20
TABLE-2.4
COAL CONSUMPTION
Sr. No. Power Generation
Coal Consumption
Existing (TPD) Upon expansion
(TPD)
1 1 x 60 MW 1,000 1,000
2 1 x 135 MW -- 1,952
3 1 X 350 MW -- 4,760
Total 1,000 7,712
Annual requirement 0.30 MTPA 2.31 MTPA
TABLE-2.5
INDONESIAN COAL CHARACTERISTICS
Sr. No. Particulars Properties
1 Gross Calorific Value 4,500 kcal/kg
2 Moisture 9.0 %
3 Ash 9.0%
4 Fixed Carbon 41.0%
5 Sulphur 0.5%
6 Volatile Matter 39.0 %
2.4.3 Power Evacuation
Power evacuation will be from Thervaikandigai, which is located 14.0 km from site
and hence a new transmission line will be erected.
2.4.4 Man power requirement
The total manpower of the existing plant is about 150 employees. Upon
expansion, additional 200 employees will be required, which includes officers and
supervisors also. The break-up of manpower requirement is given in Table-2.6.
TABLE-2.6
MAN POWER DEMAND
Sr. No. Category No. of persons
1 Managers / officers 20
2 Technical / administrative assistants 40
3 Skilled /semiskilled workers 140
Total 200
Rapid Environmental Impact Assessment for the proposed augmentation
& expansion of existing thermal power plant at Gummidipoondi,
Thiruvallur District, Tamilnadu
Chapter – 2
Project Description
VIMTA Labs Limited, Hyderabad/Coimbatore 21
2.4.5 Water Requirement
The water requirement of the existing and the proposed activity will be obtained
from the existing borewells itself. Rain water harvesting reservoir (70 MLD) has
been constructed for harvesting rainwater through storm water drains. Additional
rain water reservoir is also proposed to be constructed for additional water demand
for the expansion activities. The total water demand for the plant after the
proposed expansion will be 240 KLD with a daily fresh water requirement of 79.84
KLD. About 160.16 KLD of treated wastewater will be reused for the process
requirement (Boiler make-up / DM Plant). The break-up of the water requirement
details are given in Table - 2.7.
TABLE-2.7
WATER DEMAND
Sr. No. Power Generation Water Requirement
Existing (KLD) Upon expansion (KLD)
1. 60 MW 48.0 48.0
2. 1 x 135 MW +
1 X 350 MW -- 192.0
Total 48.0
(0.039 cusec)
240.0
(0.098 cusec)
Description Water Quantity (KLD)
DM water for boiler make-up 193.0
Domestic consumption 16.0
DM plant regeneration 31.0
Total 240 (0.098 cusec)
Rapid Environmental Impact Assessment for the proposed augmentation
& expansion of existing thermal power plant at Gummidipoondi,
Thiruvallur District, Tamilnadu
Chapter – 2
Project Description
VIMTA Labs Limited, Hyderabad/Coimbatore 22
FIGURE - 2.2
WATER BALANCE (UPON EXPANSION)
All Values are in KLD
Raw Water 240
Boiler Make-up 1 x 60 MW
Boiler Make-up 1
x 135 MW & 1 x 350 MW
Domestic Consumption 1 x 60 MW
Domestic Consumption 1 x 135 MW & 1 x 350 MW
STP
Cooling Pond I
Cooling Pond II
Guard Pond
R O Rejects
DM PLANT 1 x 60 MW
DM PLANT 1 x 135 MW & 1 x 350 MW
Neutralization Pit
RO Plant
Ground Water /Rain Water
Reservoir
160.16
160.16
36
157 138
35
6
25 25
6
31
173
173
204
43.84
Ash Quenching & Coal Dust Suppression
6
10
4.8
8.0
43.84
Greenbelt
79.84
Rapid Environmental Impact Assessment for the proposed augmentation
& expansion of existing thermal power plant at Gummidipoondi,
Thiruvallur District, Tamilnadu
Chapter – 2
Project Description
VIMTA Labs Limited, Hyderabad/Coimbatore 23
2.4.6 Infrastructure
Availability of infrastructure facilities like railways and road access to the site
for ease of transportation of equipment and fuel etc.;
Facility for interconnection with transmission and distribution system for
evacuation of power;
Optimum investment requirement for development of the infrastructure; and
Availability of medical, education, market and railway station within an
accessible distance.
Roads
The approach road for the plant will be from NH – 5. As a national highway, the
road will be suitable for carrying heavy equipment. The internal roads are
available to provide access to different areas of the plant.
All internal plant roads will be 7.0 m wide black topping with 1.5 m wide
shoulders on both sides of the road. Single lane roads will be of 4.0 m wide black
topping with 1.0 m wide shoulders on both sides of the road. Access roads to
building/facilities will generally be single lane roads without shoulders.
Drainage
Lined open drains are being provided at the plant site to carry the surface run-
off; these drains will run alongside the roads and will lead to the final disposal
point. Plinth protection provided around buildings will slope to the drains.
Reinforced concrete culverts or concrete pipe culverts will be provided at road
crossings.
Sewerage System
Sewage from the existing plant and from the proposed buildings and facilities will
be routed into a sewage treatment plant through a sewerage concrete pipe.
Manholes shall be provided at every junctions. A permanent sewage treatment
plant shall cater to the sewage discharge of the plant. The treated water will be
utilized for the greenbelt maintenance.
Landscaping
Landscaping has been already developed within the existing plant premises and
will also be developed for the additional plant area. Necessary afforestation/
green belt development work will be carried out as per the stipulation of Ministry
of Environment & Forests. Plants and tree saplings planted will be maintained and
irrigated by usage of treated sewage from the plant.
Rapid Environmental Impact Assessment for the proposed augmentation
& expansion of existing thermal power plant at Gummidipoondi,
Thiruvallur District, Tamilnadu
Chapter – 2
Project Description
VIMTA Labs Limited, Hyderabad/Coimbatore 24
2.4.7 Infrastructure for Labour
The basic amenities for the labour force during erection and operation phase are
proposed. The facilities comprises of the following:
Separate shelters will be provided for male and female labours for resting;
Separate wash rooms (sanitary facilities) will be provided for male and female
labours;
The contractors will be directed to provide fuel to labours for cooking;
First aid facilities will be made available; and
Drinking water will be provided.
2.5 Project schedule for Implementation
The erection and commissioning activities for the proposed expansion will be
completed by December, 2017 subject to receipt of all approvals from statutory
authorities.
i. BTG orders to place - October, 2015;
ii. Commencement of civil works - December, 2015;
iii. Commencement of boiler erection - April, 2016;
iv. Boiler hydro test - March, 2017;
v. Synchronization - November, 2017;
vi. Commissioning - December, 2017.
2.6 Technology and Process Description
Various utilities are being maintained and will be provided for the smooth and
efficient functioning of the existing & proposed plant. The proposed utilities are
discussed in subsequent sections. The process flow of the plant is given in
Figure-2.3.
2.6.1 Plant Layout
The general topography of the land for the main plant is plain. The land area is
free of any forest and with minimum habitation. No cultivation is being carried-
out in the additional land allotted for the proposed unit.
The general layout plan for the proposed units (1 x 135 MW & 1 X 350 MW) has
been worked out taking into consideration the various aspects like available land,
ground features, ground contour, corridor for outgoing transmission lines,
road/rail approaches, railway siding arrangement for coal transportation, wagon
tipplers, prevailing wind direction and location of ACC, strategically locating major
plant equipment etc.,
An area of 5.69 ha has been identified for installation of the proposed 1 x 135 MW
& 1 x 350 MW units. This land area is considered including space for installation
of boilers (0.78 ha), turbine generator hall (0.82 ha), air cooled condenser (1.54
ha), water treatment plant (0.35 ha), ESP & chimney (0.53 ha), Switch yard
(1.67 ha). Coal storage yard has been proposed in an area of 1.55 ha. Buffer
zone for plantation as required for such installation has also been considered.
Rapid Environmental Impact Assessment for the proposed augmentation
& expansion of existing thermal power plant at Gummidipoondi,
Thiruvallur District, Tamilnadu
Chapter – 2
Project Description
VIMTA Labs Limited, Hyderabad/Coimbatore 25
Ash dyke (Existing – 0.64 ha + Proposed 2.61 ha = 3.25 ha) is allocated for
temporary dumping of bottom ash (6 years) and unsold fly ash for approx. 2
years. Considering 15 M height (5m below ground and 10m above ground), about
3.25 ha of land has been earmarked for dumping ash generated from the plant
for a period of 2 years (As per CEA norms, Beginning from the 1st year, every
year 10% of the Fly ash to be utilized and after 10 years 100% Fly ash generated
should be utilized). This will cater for dumping of bottom ash for 6 years and 10%
quantity of fly ash for 2 years.
It is proposed to fill the low lying areas in the vicinity with the bottom ash for
area development. Bottom ash also has a ready market as building material for
uses such as landfill etc. Entrepreneurs will be encouraged to use fly ash for
manufacturing bricks, tiles, light aggregates etc.,
Greenbelt will be provided in the proposed plant area in addition to the existing
greenbelt all along the periphery of the plant site boundary, ash dyke area, partly
along raw water reservoir area and any vacant area lying within the plant site.
2.6.2 Mechanical Equipment and Systems
Thermodynamic Cycle
The proposed units will be a conventional thermal power plant operating on sub
critical pressure (1 x 135 MW) & super critical pressure (1 x 350 MW), single
reheat steam cycle with regenerative feed heating arrangement.
Sub critical operation (Exis. 1 x 60 MW; Prop. 1 x 135 MW)
The superheated steam from the boilers at 170 bar and 537ºC is supplied to the
High Pressure (HP) turbine. This steam, after expansion in the HP turbine is sent
back to the boiler as cold reheat steam. After reheating in the boiler, the
reheated steam (Hot reheat steam) at about 42 bar and 537 ºC is sent to
Intermediate Pressure (IP) and Low Pressure (LP) turbine and is finally exhausted
into the condenser.
The exhaust steam is cooled and condensed in the air cooled condenser.
Rapid Environmental Impact Assessment for the proposed augmentation
& expansion of existing thermal power plant at Gummidipoondi,
Thiruvallur District, Tamilnadu
Chapter – 2
Project Description
VIMTA Labs Limited, Hyderabad/Coimbatore 26
FIGURE-2.3
POWER GENERATION FLOW SCHEME
Rapid Environmental Impact Assessment for the proposed augmentation
& expansion of existing thermal power plant at Gummidipoondi,
Thiruvallur District, Tamilnadu
Chapter – 2
Project Description
VIMTA Labs Limited, Hyderabad/Coimbatore 27
The feed heating system consists of 4 stages of low pressure (LP) heaters in
series, one gland steam condenser, one separate drain cooler for low pressure
heater, one deaerator and 3 stages of high pressure (HP) heaters in series.
The condensate from the hot well of each condenser is extracted by 2 x 100%
capacity condensate extraction pumps (1W + 1S) and is pumped to the deaerator
through gland steam condenser, drain cooler and LP heaters. The feed water is
de-aerated in the deaerator and is collected in feed water storage tank. Water
from this tank is drawn by the boiler feed pumps and is pumped to the boiler
through the HP heaters. 3 x 50% capacity feed water pumps have been
envisaged for each unit.
Condensate in the LP heaters and feed water in HP heaters is heated
progressively by bled steam drawn from Cold reheat line and extraction steam of
the IP and LP turbine. Condensate drain from the HP heaters will be cascaded to
the deaerator feed storage tank and drain from the LP heaters would be cascaded
to the condenser through the drain cooler.
The auxiliary steam for the power station is drawn from main steam line and after
pressure reduction and desuperheating is used for de-aeration, turbine gland
sealing, etc. Provision for steam supply to auxiliary steam system from cold
reheat piping through adequately sized pressure reducing and desuperheating
station will also be there.
The unit is also provided with HP and LP bypass system for quick hot start and
boiler stability with large load rejections.
Description of major plant and equipment of a typical power plant unit is given
hereunder.
Steam generator & accessories
The steam generator which would be designed for firing 100% coal would be
radiant, reheat, natural circulation, single drum, balanced draft. Semi-outdoor
type of unit rated to deliver 939.7 t/hr of superheated steam at 170 bar, 537OC
when supplied with feed water at a temperature of 253.7°C at economiser inlet.
The steam generator would be provided with six mill type coal pulverisers along
with individual raw coal feeders and coal bunkers. The boiler would be designed
to handle and burn HFO/LSHS oil as secondary fuel up to 22.5% MCR capacity for
startup and low-load operation.
The boiler would also be provided with light diesel oil (LDO) firing system having
a capacity corresponding to about 7.5% MCR for warm-up during start-up. The
required fuel oil and light fuel oil pressurizing units and fuel oil heating equipment
will be provided. High energy arc (HEA) ignitors would be provided to ignite LDO
as well as fuel oil.
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The steam generator would consist of a corner fired water cooled furnace, radiant
and convection superheaters, reheaters, attemperators, economiser, regenerative
air heaters, Steam coil air heaters etc. The draft plant comprises 2x60% axial
forced draft fans, 2x60% radial induced draft fans and 2x60% radial type primary
air fans. Electrostatic precipitators and fly ash hoppers with associated
ducting/piping would be provided for the collection of ash. Soot blowers would be
provided at strategic locations and would be designed for sequential automatic
operation from the unit control room.
Turbine Generator Unit
The steam turbine would be rated for 135 MW maximum continuous output, at
the generator terminals, with throttle steam conditions of 170 bar pressure and
537OC superheat, 537OC reheat temperature, 0.1033 kg/cm2 back pressure and,
all feed water "heaters in service. The steam turbine would be a reheat,
condensing unit tandem compound with a double exhaust LP turbine. The generator would be rated for 135 MW, 3 phase, 50Hz, 3000 rpm and 0.8 pf.
The generator stator would be water cooled. The rotor would be suitable for
conventional hydrogen cooling, with the windings cooled with hydrogen circulated
by fans mounted on the rotor. The turbine-generator would be complete with all accessories customarily
supplied by turbine-generator manufacturer such as protective system, lube and
control oil systems, seal oil system. Jacking oil system, seal steam system,
turbine drain system. HP/LP bypass system. Electro-hydraulic control system,
automatic turbine run-up system. on-line automatic turbine test system and
turbine supervisory instrumentation. The turbine-generator would also have all
necessary indicating and control devices to permit the unit to be placed on
turning gear, to be rolled, accelerated and synchronized automatically from the
control room. Other turbine-generator accessories would include an oil
purification unit with transfer pumps and clean and dirty oil storage tanks of
adequate capacity.
The condensing plant would comprise double-pass surface type condenser of
single shell construction. The condenser would be mounted on spring supports
designed to take up its own and turbine exhaust hood thermal expansion.
1x100% capacity priming vacuum pump would be provided to create vacuum in
the condenser during start-up and 2x100% capacity main vacuum pumps to
remove the non-condensible gases liberated during normal operation. Mechanical vacuum pumps are motor driven and unlike steam jet air ejectors do
not require any motive steam. Vacuum pumps are therefore more convenient for
unit start-up and are preferred.
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The unit would be provided with a 60% HP-LP bypass system. a) To prevent a boiler trip in the event of a full export load throw-off and
maintain the unit in operation at house load.
b) To prevent a boiler trip following a turbine trip and enable quick restart of
the turbo set.
c) To minimise warm restart deviations of the unit after a trip.
d) To conserve condensate during start-up e) To facilitate quick load changes in both directions without affecting the
steam generator operation during start-up. Air Cooled Condenser
Air cooled condenser is typically of A-frame design. This design not only
facilitates condensate draining and collection but it also ensures that there
is no dead zone in the heat transfer surface and there is high operating
stability during load transients.
The vapour inlet header constituents the apex of the ‘A’. A large diameter
and comparatively lengthy pipe connects this header to the exhaust from
low pressure stage of the turbine and its large volume makes this inlet
subsystem prone to air leakage as well as requiring a longer time to
evacuate during plant start up. At the bottom of the A-frame are two
outlet headers, each connected to the inlet headers by banks of finned
tube.
Most of the panels on ACC are of parallel type, both condensing vapour
and condensate flow together down insides of the pipe. Piping also
connects the two outlet headers together, allowing the vapour to pass from
one side to other as well as the condensate to be collected. Whereas in
counter flow arrangement, the vapour rising up into the tube banks from
outlet headers while the condensate flows back down to these headers so
that it can be collected and withdrawn. Meanwhile, the upper ends of the
tubes in these section are connected to their own headers which are
provided with steam jet air ejectors for removal of non-condesibles.
The finned tubes are necessary because of the low thermal conductivity, low
density and low heat capacity of air. The large surface area required to obtain a
given heat removal rate, the area increasing with the design ambient air
temperature.
Major components of ACC
Condensing & venting modules
Air movement equipments
Windwall andmodule partition walls
Air evacuation equipment with piping
Condensate collection headers
Condensate storage tank and pumping system
Exhaust steam ducting with expansion joints
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Fin cleaning system
Instrumentation & controls
Pressure relief device (rupture disc)for protection of ducting
Steam duct condensate draining system
Electricals – VFD, MCC, cables etc
Wet Cooling System vs Dry Cooling System
Air cooled condenser have become the need of the hour than the conventional
method due to depletion of the water source. It is very well known fact, water is
becoming a scarce natural source. Using water for thermal power plant has
negative impact on environment and ecology. Besides this cost of storage, pump
and treatment of water for cooling power application is a major concern.
System Wet Cooling System Dry Cooling System
Availability of coolant Water is scarce hence it
has become costly
Air is free
Maintenance cost High 25 % of wet cooling system
Effluent treatment Necessary Not required
Fouling and Scaling Major concern Not required
Cleaning Frequent tube cleaning is
required
Occasional fin cleaning is
required
Infrastructure Pumping system and
storage system required
Not required
Annual energy
consumption
High Low
Condensing Equipment and Accessories
Condensate Pumps
Two 100% capacity condensate pumps, one working and one standby would be
provided. The pumps would be vertical, canister type, multistage centrifugal
pumps driven by AC motors.
Boiler Feed Pumps
Three 50% capacity motor driven boiler feed pumps would be provided to pump
the feed water from the deaerator to the steam generator through the high
pressure heaters. Two pumps would normally be in operation, with the third as
standby. The boiler feed pumps would be horizontal, multistage centrifugal
pumps of barrel type. Each boiler feed pump would be provided with a booster
pump driven from the same shaft as the main pump. Each boiler feed pump
would be provided with a variable speed hydraulic coupling, with built-in step-up
gear to regulate the boiler feed pump speed.
Low Pressure Heaters
The three low pressure heaters, namely 1, 2 & 3 would be of surface type
designed for vertical mounting with U-shaped stainless steel tubes, with their
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ends rolled in carbon steel tube sheets. Low pressure heater No.1 would be
provided with an external drain cooler.
Deaerator
The deaerating feed water heater would be a direct contact, variable pressure
type of heater with a spray or spray tray type of deaeration arrangement. The
feed water storage tank would have a storage capacity adequate to feed the
boiler for 10 minutes when operating at MCR conditions.
Gland Steam Condenser
A surface type gland steam condenser would be used to condense the gland
steam exhausted from the turbine glands. The gland steam condenser would be
of single-pass type with the main condensate flowing through the tubes to
condense the steam. Exhausters would be provided to evacuate the air from the
shell side and maintain the shell at the required negative pressure.
High Pressure Heaters
The two high pressure heaters, namely 5 & 6 would be of surface type designed
for vertical mounting with stainless steel-tubes welded into stainless steel clad
tube sheets. Both HP heaters would be provided with a desuperheating zone and
a drain cooling zone in addition to the condensing zone.
Super critical operation (Proposed 1 x 350 MW)
Steam Generator
The Steam Generator shall be of forced or assisted circulation with super-critical
steam parameters, once through type, single reheat arrangement for firing
pulverized coal. The steam generator shall be drum less, but shall include two (2)
nos. of separators and 1 x 100% start-up drain recirculation pump along with all
other necessary auxiliaries.
TABLE-2.8
STEAM GENERATOR SPECIFICATIONS
Sr. No. Parameters Data
1 Main Super-heated steam pressure 258bar (a)
2 Main Super-heated steam temperature 588ºC
3 CRH inlet pressure 53.16 bar (a)
4 CRH inlet Temperature 343ºC
5 HRH outlet pressure 48.107 bar (a)
6 HRH outlet temperature 585ºC
7 Feed water inlet temperature 289 ºC
8 Fuel used
Raw Coal LDO for start-up & HFO for
stabilization up to 30% BMCR condition
9 Gross Calorific value of Coal 4220 Kcal/Kg - Imported coal
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The steam generator shall be designed for satisfactory, continuous and reliable
operation at high efficiency with the range of coal being provided to this thermal
power plant with minimum requirement of support fuel oil for flame stabilization
within its control range. The furnace design shall have adequate residence time
provided to burn the fuel completely. The Steam Generator shall be designed to
fire the blended coal having 70% of imported coal and 30% of Indian coal. Each
steam generator shall have suitable pulverized coal firing arrangement comprising
coal bunkers with 16 hours storage capacity. Gravimetric raw coal feeders,
pulverizing mills (vertical/horizontal) and other required auxiliaries will be
installed.
The milling system will be sized to ensure rated performance for lifetime.
Selection of the number of mills shall consider one ready standby pulveriser mill
to achieve BMCR while the steam generator is fired with worst coal. The mill
capacity selection shall be based on 90% loading with worst coal with all mills
operating.
The steam generating unit shall be provided with LDO pressurizing units for
supplying LDO to oil burners during boiler cold and hot start-ups and HFO for
flame stabilisation with coal firing during low load operations up to maximum
30% BMCR load.
For maintaining the steam temperature control range (rated steam temperature
of 569 ± 5°C) within the prescribed limits at the outlet of super-heater and re-
heater, de-superheating stations will be provided. The water required for de-
superheating shall be tapped off at the outlet of the steam generator feed water
pumps to control the final steam temperature between 60% to 100% MCR load.
Tilting Burners will also be used to control Reheat temperature
2 x 60% RAPH will be provided for each steam generator for primary and
secondary air heating. SCAPH will be provided at the discharge duct of each F.D.
fan, and will be installed close to the regenerative air heater. The SCAPH will be
of modular construction type with fin tubes and will be designed to maintain the
cold end temperature above acid dew point temperature during steam generator
start-up and low load operations.
The steam generator balanced draft system per unit will be provided with two (2)
sets of FD fans, two (2) sets of ID fans, and two (2) sets of PA fans; each set
rated for 60% of BMCR (Steam generator MCR) capacity. The FD fans may be of
constant speed, axial flow type with hydraulic blade pitch control; ID fan of radial,
backward curved type with VFD and the PA fan of constant speed, centrifugal
type with variable blade pitch control. All necessary regulating and isolating
dampers will be provided to all fans for safe, efficient and convenient operation of
the steam generator.
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Turbine Generator Unit
The steam turbine would be tandem compounded, single reheat, condensing,
horizontally split machine with uncontrolled extractions for Four (4) LP heaters,
Three (3) HP heaters and One(1) Deaerator. The steam turbine will consist of
proven HP turbine, IP turbine, and LP turbine modules. However the final number
of heaters will depend upon the steam turbine supplier selected for this project.
The turbine will have a lubricating oil system for supplying oil to turbine and
generator bearings and also to hydrogen seal oil system of the generator. The
lubricating oil will be cooled by closed circuit cooling water system water as
cooling medium.
Necessary protective & supervisory system will be provided to ensure trouble-
free, safe and efficient operation of the turbine generator.
TABLE-2.9
TURBINE SPECIFICATIONS
Sr. No. Description Units
Design
Parameters
1 Main Steam Inlet Pressure Bar(a) 255
2 Main Steam Inlet Temperature ºC 585
3 Reheat steam inlet pressure Bar(a) 48.107
4 Reheat steam inlet temperature ºC 585
5 Exhaust pressure Bar(a) 0.18 – 0.2
6 Feed water temperature at last
HP heater outlet ºC 289
7 Valve Wide Open Flow % MCR 105
8 Turbine rating MW 350
The generator would be rated suitably with 3 phase, 50Hz, 3000 rpm and 0.8 pf.
The generator stator would be water cooled. The rotor would be suitable for
conventional hydrogen cooling, with the windings cooled with hydrogen circulated
by fans mounted on the rotor.
The turbine-generator would be complete with all accessories customarily
supplied by turbine-generator manufacturer such as protective system, lube and
control oil systems, seal oil system. Jacking oil system, seal steam system,
turbine drain system, HP/LP bypasses system, Electro-hydraulic control system,
automatic turbine run-up system, On-line automatic turbine test system and
turbine supervisory instrumentation. The turbine- generator would also have all
necessary indicating and control devices to permit the unit to be placed on
turning gear, to be rolled, accelerated and synchronized automatically from the
control room. Other turbine-generator accessories would include an oil
purification unit with transfer pumps and clean and dirty oil storage tanks of
adequate capacity.
The condensing plant would comprise of Air cooled condenser of single row
construction. 1 x 100% capacity priming vacuum pump would be provided to
create vacuum in the condenser during start-up and 2 x 100% capacity main
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vacuum pumps to remove the non-condensable gases liberated during normal
operation. Mechanical vacuum pumps are motor driven and unlike steam jet air
ejectors do not require any motive steam. Vacuum pumps are therefore more
convenient for unit start-up and are preferred. The unit would be provided with a
60% HP-LP bypass system.
i. To prevent a boiler trip in the event of a full export load throw-off and
maintain the unit in operation at house load;
ii. To prevent a boiler trip following a turbine trip and enable quick restart of
the turbo set;
iii. To minimise warm restart deviations of the unit after a trip;
iv. To conserve condensate during start-up;
v. To facilitate quick load changes in both directions without affecting the
steam generator operation during start-up.
Condensate Pumps
Unit shall comprise of 3 x 50% capacity CEPs. The CEP will be designed for 10%
Margin in capacity and 10% margin in head over and above the pump sizing
consideration indicated below. The condensate extraction pumps will be vertical;
multi stage, enclosed can type with flanged connection driven by electric motor.
Boiler Feed Pumps
Three 50% capacity motor driven boiler feed pumps would be provided to pump
the feed water from the deaerator to the steam generator through the high
pressure heaters. Two pumps would normally be in operation, with the third as
standby. The boiler feed pumps would be horizontal, multistage centrifugal
pumps of barrel type. Each boiler feed pump would be provided with a booster
pump driven from the same shaft as the main pump. Each boiler feed pump
would be provided with a variable speed hydraulic coupling, with built-in step-up
gear to regulate the boiler feed pump speed.
Regenerative Feed Water Heating System
Regenerative feed heating system is envisaged for the turbine cycle to improve
the efficiency. The feed heating system with four (4) numbers of LP heaters, one
number direct contact type deaerating heater and three (3) numbers of HP
heaters are foreseen for this type of unit. HP and LP feed heaters will be tube and
shell type. LP feed heaters will be of horizontal and U-tube type with integral
drain cooler. HP heaters will be horizontal and U-tube type with integral
desuperheating, condensing and drain cooling sections
Deaerator
For deaerating and heating of the feed water the unit will be provided with a
spray-cum-tray type deaerating heater with a horizontal feed water storage tank
of 6 minutes capacity of steam generator MCR condition. The deaerator will be
capable of deaerating all the incoming condensate from LP feed water heaters
and drains from HP feed water heaters to provide steam generator feed to match
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the steam generator MCR requirements continuously. The deaerator will be
designed to keep the oxygen content of the condensate below 0.005 cc/litre with
zero carbon dioxide. Deaerator will normally operate by taking extraction steam
from IP turbine casing. However, during low load operation and start-up, the
deaerator will be pegged with steam drawn from auxiliary header
Gland Steam Condenser
A surface type gland steam condenser would be used to condense the gland
steam exhausted from the turbine glands. The gland steam condenser would be
of single-pass type with the main condensate flowing through the tubes to
condense the steam. Exhausters would be provided to evacuate the air from the
shell side and maintain the shell at the required negative pressure.
Condensate Polishing Unit
Online condensate polishing unit of full-flow Mixed bed type is envisaged to treat
the condensate to maintain desired quality of condensate water as
recommended by BTG manufacturer. The CPU shall also be capable of
maintaining the desired condensate quality during start-up and condenser tube
leakage
Electrostatic Precipitator (ESP)
Steam generating unit shall be provided with the required electrostatic
precipitator (ESP). ESP shall have two parallel gas paths; one gas path can be
isolated for maintenance while the other path being in operation. Each path shall
comprise of the required number of fields in series for collection of fly ash. The
ESP will have efficiency of around 99.9%. The ESP will have adequate number of
ash hoppers provided with electric heaters. ESP will be provided with
Microprocessor based controller. The design of ESP shall be such that the outlet
dust burden or solid particulate matter (SPM) content at its outlet does not
exceed 50 mg/Nm³ at 100% BMCR with worst coal, with one field out of service.
2.7 Plant Water System
The requirement of water for the plant will be for meeting the following
requirement:
i. Make-up For the re-circulating Auxiliary cooling water system
ii. Power cycle make-up (through D.M plant)
iii. Make-up to the air-conditioning and air washer system
iv. Drinking Water
v. Service Water
vi. Dust suppression system
vii. For maintaining greenery
The source of water for the plant is existing borewells & rain water harvesting
system. Water will be collected in a raw water reservoir through a well-developed
rain water harvesting system and the plant drains which will be pre-treated and
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then treated to the required levels for usage in the plant. The total water demand
of the TPP is 240 KLD. A raw water reservoir of 60 MLD capacity is established
which would cater to the required water quantity. From the plant water reservoir,
the water is fed to clarifiers. Clarified water will be feed for Filtration Plant, which
will cater the needs of treated/soft water requirements of the plant.
Raw Water reservoir
A raw water reservoir of capacity 60 MLD is provided. The raw water reservoir at
site will be of earthen construction with suitable lining.
Water Pre-Treatment Plant
The purpose of pre-treatment system is to treat the raw water from raw water
storage tank and reduce the suspended solids and any organics prior to
downstream use. Raw water is pumped by means of 2 x 100% plant make up
pumps through 2 x 50 % Solid Contact Clarifiers for reduction of suspended
solids. The overflow of the clarifiers will be taken to clarified water storage RCC
tank. The clarified water feed to the DM plant will be pumped through multimedia
filters for further reduction in suspended solids and led to a filtered water storage
tank for downstream use.
The clarified water is used for:
i. Makeup for HVAC system;
ii. Service water system;
iii. Fire water system.
Filtered water is also used for potable water requirement after suitable
chlorination. Filtered water storage tank will have a total capacity of 8 hours
consumptive requirements.
The filtered water is used as
i. Inlet water to DM plant;
ii. Potable water;
iii. Coal handling plant requirements other than dust Suppression Plant and
equipment use including boiler blow down tanks quench;
iv. Miscellaneous uses.
Pre-treatment chemicals such as alum, lime and polyelectrolyte will be dosed at
inlet to the clarifier. A sludge sump will be provided and the collected sludge will
be transported to sludge thickener for further treatment and disposal.
Chlorination with sodium hypochlorite will be done at the outlet of clarifier. The
pre-treatment plant will be complete with 2 x 50% Solid Contact Clarifiers and
associated chemical storage, handling and dosing system, sludge handling
system, 2 x 100% multi grade filters, backwash pumps, backwash waste
collection tank and transfer pumps, RCC clarified water storage tank, filtered
water storage tank, all piping, valves and instruments as required. The system is
sized based on the Design Raw Water Analysis. The clarified water and filtered
water requirement will be based on downstream consumptions of systems.
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DM Plant
The purpose of the Cycle Make-Up Treatment (DM) System is to produce
Demineralized water of required quality and quantity for steam cycle. The DM
plant will treat filtered water to produce Demineralized water for make up to
steam cycle, closed cooling water system and miscellaneous use during
maintenance operation. 2 X 100% (1W + 1 S) each of 35m³/hr (Net Output
Capacity) streams will be provided. The net demineralized water that can be
produced from each stream will be 700 m³/day.
The Cation & Anion Exchangers service and regeneration cycle is 20 hours and 4
hours respectively. Mixed Bed (MB) unit will be regenerated once in 7 days.
Regeneration of Cation & Anion vessels is by counter current mode and
regeneration of MB is in concurrent mode. The DM water is stored in two DM
water tanks of each capacity 500 m3. It is further distributed to various user
points.
Regeneration system for Cation Exchangers consists of Acid Storage Tank and
Acid Measuring Tanks for Cation exchanger and Mixed Bed (Cation) Exchanger.
Regeneration system for Anion Exchanger consists of Caustic Storage tank and
Caustic Dilution Tank for Anion exchanger, Neutralization pit and Mixed Bed
(Anion) exchanger. Transfer Pumps are envisaged for Transfer of Acid/Alkali from
tankers to the storage tanks. Ejectors are used for injection of Regeneration
chemicals. Acid & Alkali storage tanks will be sized to store 30 days requirement
of chemicals.
Waste Water Treatment System
The Waste Water Treatment system envisaged will cover all the plant wastewater
which are to be disposed. The objective of the treatment is to make the
wastewater suitable for disposal as per the guidelines of the State Pollution
Control Board (PCB). All the wastewater after treatment will be fed to the
common monitoring basin to ensure that the effluent meets the PCB stipulations
before reuse within the plant and or disposal outside the plant.
The details of various waste water sources and their treatment schemes are given
in Table-2.10.
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TABLE-2.10
SOURCES OF WASTEWATER AND ITS MANAGEMENT
Sources of wastewater Treatment & Disposal
Runoff Water From Coal Yard
The runoff from the coal yard will be collected in a settling tank. The clear water will be taken to a collection tank and used for watering of green belt
Runoff Water From
Limestone Yard
The runoff from the limestone yard
will be collected in a settling tank. The clear water will be taken to a collection tank and used for watering of green belt
Neutralized Waste Water Make-up water treatment plant waste will
be taken to separate neutralization pit, neutralized and then pumped to the Common Monitoring Basin (CMB)
Oily Waste Water Oil bearing effluent generated from fuel oil handling area plant floor wash etc. will be treated in an oil/water separator to
separate oil from water and the treated waste water sent to CMB. The oily sludge will be collected and disposed offsite
Sewage Water from Toilets in the Power Plant
The Sewage water generated from the Power Plant will be treated in an anaerobic
filter and the treated effluent will be collected and used for horticulture. Suitable arrangements for collection of sludge, its compaction and safe disposal will be provided
Boiler Blow Down Boiler blow down waste water will be
fed to neutralization pit of water treatment plant and from there it will be sent CMB
Special Waste Water Special waste water like Air Preheater washing water, acid cleaning of boiler etc. will be collected and treated in a chemical
waste cleaning plant to make it suitable for offsite disposal
Clarifier Sludge The sludge collected in the clarifier will be taken to a sedimentation tank and the
clear water will be sent to CMB. The collected sludge will be taken to a sludge
drying bed and spread over the green belt within the plant boundaries
Common Monitoring Basin
The outlet from the CMB after ensuring that the quality meets the requirements stipulated in the PCB norms, will be used
for coal yard dust suppression, limestone dust suppression and watering of green belt
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Chlorination System
Raw water chlorination plant is required to dose chlorine in the clarifier during
pre-treatment stage. It is dosed to remove the organic matters present in the raw
water. Sodium hypochlorite dosing will be provided for chlorination of raw water.
The chlorination system consists of sodium hypochlorite dosing tank and dosing
pumps.
Chemical Feed System
Although high purity water will be used as heat cycle make-up, careful chemical
conditioning of the feed steam condensate cycle is essential as a safeguard
against corrosion and possible scale formation due to ingress of contaminants in
the make-up system. Chemical feed system will comprise of the following:
A) Hydrazine System
The most harmful contaminant, which is always present in the make-up water,
causing serious corrosion in the high-pressure boiler is dissolved oxygen.
Hydrazine solution will be used as a de-oxygenator, to wipe off traces of dissolved
oxygen left over in the feed water after deaerator. Hydrazine solution will be
prepared in a solution tank. Water from the condensate pump discharge header
will be used as the diluting medium.
Dosing pump will deliver hydrazine solution at controlled rates continuously at the
condensate pump discharge headers and/or boiler feed pump suction lines. A
dosing pump will be provided.
B) Phosphate Dosing System
The rate of corrosion on mild steel surface is lowest when the solution in contact
has a pH within 9 to 10. Proper attention is required so that the alkalinity does
not become excessive, as in such case the corrosion rate will go on increasing. To
impart desired alkalinity to boiler water and also to safely remove scale-forming
compound in water, if any, due to system contamination as non-adherent
harmless precipitate, tri-sodium phosphate solution will be added in the boiler
drum. Phosphate solution will be prepared in a common tank. Water from the
condensate pump discharge header will be used as the solvent. The solution will
be transferred to individual metering tanks, from which respective phosphate
dosing pumps will inject the solution to respective boiler drums are required.
Potable Water Treatment Plant
The purpose of potable water treatment system is to treat the water from filter
water tank to disinfect prior to downstream use. Filtered water, from filtered
water tank, is pumped to the overhead potable water storage tank. This water is
chlorinated by dosing sodium hypochlorite in the line for disinfections and makes
the water suitable for potable purposes.
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Service Water System
Clarified water will be used as service water. Clarified water will be pumped from
the clarified water storage tank with the help of 2 x 100% service water transfer
pumps to overhead service water tank. Further distribution for various points of
use will be done from this tank by gravity except for boiler floor wash for which
the water will be pumped using booster pumps.
Closed cooling Water (CCW) System
The CCW system will be provided as part of the SG & auxiliaries and STG &
auxiliaries which will meet the cooling water requirements of all the auxiliary
equipment of the STG and SG units such as turbine lube oil coolers, generator air
cooler, exciter air coolers, ID/SA/PA fan bearing oil coolers, BFP auxiliaries such
as lube oil coolers, working oil coolers, drive motors, etc., condensate pump
bearings and sample coolers.
The total estimated aux. cooling water requirement for the above auxiliaries is
about 2500 m³/hr. A closed loop system using passivized DM water is proposed
for the CCW system. In CCW system, DM water is circulated by 2 X100% capacity
each Closed Cooling Water (CCW) pumps. The hot water from these auxiliaries is
cooled in the plate type CCW heat exchangers 2 No (1 W+1S).
An overhead expansion tank of adequate capacity is proposed to ensure positive
suction to the CCW pumps and also serve as the source of make-up to the CCW
system. Normal make- up to the CCW expansion tank is provided from the DM
water make up pumps. To minimize the corrosion, a corrosion inhibiting chemical
solution will be added to the CCW system.
2.8 Coal handling system
Design Criteria, Assumptions and System Capacity
Coal will be received in trucks from nearest Port and unloaded using hydraulic
tippers / unloading hoppers for tipper trucks. Belt conveyors, stacking, and
reclaiming, screening, crushing and conveying same to steam generator bunkers
is based on the following functional requirements and assumptions:
Coal required for 1 x 350 MW unit at MCR condition based on worst coal
having a gross calorific value of 4000 Kcal/kg is 198.5 TPH;
Storage capacity of stockpile is considered Seven (7) days at plant site.
The calculations for Coal handling system capacity considering Worst type coal
are given in Table-2.11.
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TABLE–2.11
DETAILS OF COAL HANDLING SYSTEM CAPACITY
Sr. No. Description Units Design Coal
1 Calorific value Kcal/kg 4000
2 MCR fuel consumption TPH 198.5
3 Coal consumption per day TPD 4760
4 No. of hours of CHS operation per day hours 12
5 Average capacity of coal plant for
1x350MW plant
TPH 250
6 Rated capacity of System selected
considering 12 hrs operation of the plant
TPH 500
The estimated maximum daily coal consumption for the power station will be
around 4760 tonnes. It is considered that coal of size (+) 50 mm will also be
received in the station.
Coal receipt, storage and Handling system
Raw coal of size 300 mm max will be crushed to 25 mm size in Ring granulator
type crushers ( 2 x 100%). Crushed coal will be either sent to Coal yard for
storage (capacity to hold 30 days’ requirement) or sent to bunkers for firing. One
no Stacker-cum-Reclaimer will be used to stack and reclaim the coal.
Coal handling plant (CHP) will be consisting of 3 nos. truck tipplers (2W+1S) and
3 nos unloading hoppers for tipper trucks, crushing / stacking, reclaiming from
the stockyard and conveying the same to steam generator bunkers using
travelling tippers. 2 x 100% capacity conveyor system will be provided
throughout.
Inline Magnetic separators and metal detectors will be provided at Crusher house
and bunker floor to separate magnetic and non-magnetic particles in coal. Belt
weighers and coal samplers will be provided at appropriate locations to record
the quality and quantity of coal received and utilized.
When coal is required in the boiler bunkers and primary crusher is not in
operation, coal will be reclaimed by the stacker / re-claimer and fed to boiler
bunkers through secondary crusher. An emergency reclaim ground hopper will
be provided to reclaim coal by dozers when stacker / re-claimer is not in
operation. Required no. of dozers / mobile equipment will be provided.
The stockpile of coal will have adequate storage for at least 7 days coal
consumption. The stockpile will be provided with necessary fire hydrant
system, compacting and dust suppression system.
The capacity of the conveying system from of crusher up to the boiler bunkers
onwards will be to meet the 24 hours MCR coal requirement of boiler in 12
hours. The conveyors will have 100% standby system.
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Coal samplers and belt weigh scales will be provided in the junction tower
prior to bunker feeding conveyor. Necessary inline magnetic separators and
metal detectors will be provided in the conveyors feeding the crusher house.
Bunker filling will be done by tipper conveyor arrangement. Bunker top will
be sealed to have effective dust control and ventilation system in the bunker
floor.
Dust suppression system will be provided in all the transfer towers, crusher
houses, and coal stockpile to minimize the air pollution problem. Necessary
spray system arrangement will be provided in the coal stockpile. Bunker
ventilation / dust extraction will be provided to extract the dust due to bunker
filling operation.
The coal stockpiles will be provided with ring main headers with hydrant
valves located as per the statutory requirements for fire fighting operations.
The complete coal handling system operation will be controlled from coal
handling control room located near crusher house. The stacker / reclaimer will
be operated from local station.
A PLC based safety-interlocking system for coal-handling plant will be
provided such that sequential starting/shut down of all the equipment due to
trip condition of downstream conveying equipment is ensured.
2.9 Ash Handling System
Ash handling, disposal and utilization
As per the present comprehensive Guidelines of Ministry of Environment &
Forests (MoEF) for fly ash utilization and disposal, all power stations should
provide arrangements for dry ash collection and disposal (The Gazette of India:
Extraordinary - Notification of Environment and Forests, New Delhi, dated 14th
September, 1999). In view of this, dry ash handling and disposal system has
been considered for the existing & proposed unit.
The design of ash handling system for the proposed units has been considered
based on maximum 10% ash (max.) and 0.5% Sulphur (max.) in Coal.
The following data has been considered for design of ash handling system:
a. Hourly coal firing rate at MCR condition
per unit for coal (maximum) 239 tons / hr
b. Ash content in coal considered
For the design of ash handling equipment 10% (maximum)
For ash disposal area calculations 10%
c. The system adopted for bottom ash removal will be dry system and for fly ash
removal will be vacuum-cum-pressure type pneumatic system.
d. The ash disposal will be in by means of trucks.
e. As a contingency measure, wet ash system is also considered both for bottom
ash and fly ash.
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f. Fly ash will be handled in dry and systems are designed for unloading in
trucks to facilitate selling of fly ash.
It will be ensured from the boiler manufacturer that the unburnt carbon content
in the fly ash is limited to 3% by weight, so that the fly ash is acceptable to the
cement manufacturers for using in their cement manufacturing process.
The ash generated from the plant will be about 451 TPD (0.135 MTPA)
considering ash content in the coal of 10%, and a plant load factor of 85%.
Dry bottom ash handling system
Shall allow the extraction of bottom ash coming from solid fuel fired boilers in
completely dry manner. The bottom ash handling system shall consist of a
completely robust extraction and conveying arrangement through steel belt
conveyor suitable for handling dry bottom ash including clinkers. Arrangements
shall be provided for cooling of bottom ash. The collected bottom ash shall be
crushed in the crushers and then conveyed to the bottom ash silo.
Suitable type and quantity of crushers shall be provided for crushing of bottom
ash into smaller size for meeting requirements of pneumatic conveying up to
bottom ash silo via buffer hopper. Bottom ash generation per unit will be
calculated at 100 % PLF considering generation of bottom ash at 25% of total ash
with worst coal.
The Dry bottom ash from the buffer hopper shall be pneumatically conveyed to
the bottom ash silo by positive pressure conveying system using transport air
compressors. From bottom ash silo, suitable provision shall be provided for
unloading the bottom ash into trucks or discharged for wet disposal; the slurry is
led to the bottom ash slurry sump. From the sump, the slurry is transported to
the dump area using ash slurry disposal pumps and pipelines.
Fly Ash Handling System
Ash collected in ECO hoppers shall be conveyed to the intermediate Fly ash
hoppers from here the ash shall be conveyed to the fly ash silos.
Vaccum Conveying Systems
Fly ash collected in ESP, Air Preheater duct, and APH hoppers shall be conveyed
from hoppers to buffer hoppers by vaccum system for onward pressure
transportation to storage silos for collection in dry form. Each fly ash hopper shall
be provided with manual chute isolation valve and ash intake valve below the
hopper flange.
Ash intake valves in the first three fields of the ESP shall be air assisted diffuser
intake type valves. Gravity discharge intake valves shall be provided for the rest
of the ESP fields and other APH and Duct hoppers.
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During System operation, the ash intake valve opens and fly ash shall fall under
gravity into the ash conveying pipeline (branch pipeline) running below the fly
ash hoppers.
Each branch pipe of the conveying system shall be provided with an air intake
valve thru which the atmospheric air shall enter the conveying line. Each branch
line shall be laid along the flue gas path and four such pipelines emerging out of
one ESP shall be connected to a header pipe, which shall be fed tom the bag filter
separator cum buffer hopper. Each branch pipeline shall be separated from each
other by cylinder operated isolation valve.
RCC Silos
The bottom ash and fly ash will be collected in the RCC silos. Individual silos for
bottom ash & fly ash storage have been installed for each boiler. Capacity of fly
ash silo is 791 m3 and the capacity of bottom ash silo is 216 m3. RCC silo will be
for collecting bottom ash mixture from the boilers. The bottom ash storage silo
will have 16 hours storage capacity. Fly ash silo will be for collecting fly ash. This
silo also will have adequate storage capacity.
The silos will be fitted with bag filters with the exhauster of the silo top to
displace air from the silo
Dry Ash Disposal
Through Closed Tankers
Dry Fly ash will be transported to the consumers in special construction closed
tankers. The dry fly ash from fly ash silo bottom will be filled in the closed tankers
with the help of motor operated retractable chutes to avoid fugitive ash going to
the atmosphere and causing air pollution.
Through Open Trucks (Conditioned Ash)
In one of the openings at the bottom of each ash silo, pug mill (Ash conditioner)
will be provided which will mix water in the dry ash mass to make it moist.
Conditioned fly ash coming from the ash conditioner will be transported through
open trucks to the consumers.
Ash Utilization
Non utilization of ash generated by thermal power station in India has been a big
pollution threat as huge quantity of ash is generated every year. The Govt. of
India has made guidelines to utilize the generated ash from the thermal power
station. For this, entrepreneurs are being encouraged by giving relaxation at
many fronts like supply of free dry ash, provision of land on concessional terms,
power supply on the mutual agreed terms and conditions, etc. A list of areas for
probable ash utilization is given below:
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Use of fly ash in manufacturing Pozzolona cement - Use of fly ash for
Pozzolona cement is quite prevalent in USA, Europe, Japan and other advanced
countries. As per data available many Indian cement manufacturers are also
using fly ash for manufacture of Pozzolona cement. The Govt. of India, in order to
encourage use of fly ash in manufacture of Pozzolona cement, has introduced
Indian Standard in this regard. This cement is being manufactured in India as per
Indian Standard IS: 3812, 1981.
Also possibilities for utilizing fly ash as per the following shall also be envisaged:
a) Concrete blocks.
b) Concrete
c) Screed
d) Refractory Concrete
e) Ash brick
f) Use in mine - stowing of underground mines.
g) Use as railway/road embankment
h) As waste land reclamation material
i) Use as stabilization of soil for road underbed.
Fuel Oil Handling System
The steam generators of power station will be designed for 100% Coal firing.
However, LDO and HFO will be required for start-ups, stabilization during low
load. The fuel oil facilities will be common to both the units.
Fuel Oil Requirement
Light Diesel Oil (LDO) Heavy Fuel Oil (HFO)
LDO and HFO requirement has been estimated based on 1.0 ml/kwhr (CERC
norms), which works out to approximately 4000 kilo liters per year for the power
station.
a) Light Diesel Oil (LDO) storage tanks
For storage of LDO, 2 nos. x 150 KL bulk LDO storage tanks has been
provided.
b) Fuel oil decanting/unloading facilities
LDO will be brought in road tankers from the nearest oil terminal and will be
unloaded in the storage tanks through unloading header and 2 nos. unloading
pumps.
c) LDO supply to the Steam Generation units
Two nos. of LDO pumps (1 W + 1S) will be installed for meeting the
requirement of LDO delivery to both the boiler units. Duplex filters at suction
side and at discharge side of each pump shall be provide Adequate provision
will be made in the design of piping system which will be laid overhead
supported on shop columns. The oil delivery pressure will suit the burner
requirement.
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Heavy Oil Storage Tanks
For storage of heavy oil, 2 nos. x 300 KL bulk storage tanks are provided.
Fuel Oil Decanting/Unloading Facilities
Heavy fuel oil will be brought in road tankers from the nearest oil terminal and
will be unloaded in the storage tanks through unloading header and 2 nos.
unloading pumps.
Heavy Fuel Supply to the Steam Generation Units
Four nos. of HFO pumps (2 W + 2S) will be installed for meeting the requirement
of Heavy oil delivery to both the boiler units.
Duplex filters at suction side and at discharge side of each pump shall be
provided. Oil heaters will be provided in the pump discharge.
Adequate provision will be made in the design of piping system which will be laid
overhead supported on shop columns. The oil delivery pressure will suit the
burner requirement.
Ventilation System
An elaborate ventilation system has been envisaged for the power house building,
ESP control building and other areas like air compressor room, DM plant building,
elevator machine rooms and various pump houses like ash water pump house,
filter water pump house, etc. to achieve the followings:
i) Dust-free comfortable working environment.
ii) Scavenging out structural heat gain and heat load from various equipment,
hot pipes, lighting etc.,
iii) Dilution of polluted air due to generation of obnoxious gaseous/aerosol
contaminants like acid fumes, dusts etc.,
The following areas are proposed to be ventilated:
Turbine building and tipper floor
ESP control building
Ash slurry pump house
Air compressor rooms
AC plant room
DM plant building
Miscellaneous rooms in powerhouse like cable spreader room, switch gear
room, oil room, toilet, elevator m/c room etc.
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a) Power House
Supply/exhaust ventilation: system with evaporative cooling has been
recommended for the powerhouse building. Ambient air will be drawn through
inertia filters, metallic panel filters, spray bank, moisture eliminator and will be
supplied by means of centrifugal fan to power house through ducting and grilles
to achieve proper distribution. The water sprayed will be re-circulated by means
of centrifugal pumps, piping, valves and other accessories. This is about the
supply system. 'Exhaust' system consists of axial flow roof exhaust fans with rain
protection cowl hood, short duct work etc. Part of the supplied air will be
exhausted and the rest will ex-filtrate through the various openings in the
structure, preventing infiltration of dusty air. This arrangement also ensures more
or less ambient dry bulb temperature inside power house.
Various rooms in power house e.g. Cable spreader room, switchgear room etc.
will be ventilated by means of transfer fans or by extending duct as required and
found suitable. Coal tripper floors are proposed to be provided with exhaust
system to eliminate building up to hazardous gases like carbon monoxide,
methane etc.
b) ESP Control Building (Excepting Control Room)
For ventilation of this building, ambient air will be drawn through unitary air
filtration unit compressing of fresh air intake Louvre, automatically cleanable
nylon filter (with water spray) and moisture eliminator and. supplied to the space
by means of centrifugal fan through ducting, grilles etc. The water for filter
cleaning will be re-circulated by means of centrifugal pumps. In addition to filter
cleaning, the water spray will have an evaporative cooling effect too. This will
produce some cooling as an added advantage. The supplied air will be exhausted
through wall mounted gravity operated to maintain an overpressure of 2-3 mm of
WC to reduce dust.
c) Other Buildings
Other buildings like ash water pump house, air compressor room, etc., will be
ventilated by means of dry system comprising of axial flow fan, dry filter
wherever required, cowls, ducting etc., Inside dry bulb temperature will be higher
than ambient by about 5 Degree centigrade. Fire dampers will be provided
wherever there is electrical installation.
Thermal Insulation
Insulation will be provided wherever necessary to minimize heat losses from the
equipment, piping and ducts and to ensure protection to personnel. Insulation will
be held by adequate cleats, wire nets, jackets, etc. to avoid loosening. Insulation
thickness will be so selected that the covering jacket surface temperature does
not exceed the surrounding ambient temperature by more than 15 oC. The
turbine proper will be spray insulated as recommended by the turbine supplier.
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Painting
All mechanical and electrical equipment including piping system and structures
wil1 be painted with international standards / IS standard colour-code for ease of
identification. The equipment exposed to marine environment will be painted /
coated with suitable corrosion resistant paint such as polyurethane paint.
Fire Protection System
The firefighting system will be designed in conformity with the recommendations
of the Tariff Advisory Committee of Insurance Association of India. While
designing the fire protection systems for this power station its extreme ambient
conditions need special attention. Codes and Standards of National Fire Protection
Association (NFPA) will be followed, as applicable.
The Power Plant is classified as Ordinary Hazard Occupancy as per TAC. Hence,
the entire system will be designed accordingly. The different types of fire
protection /detection system envisaged for the entire power plant are described
below.
Hydrant System for entire area of power plant
High Velocity Water Spray System (HVWS) for generator transformer, Unit
Auxiliary transformer, station transformer, and turbine lube oil canal pipe lines
in main plant, Boiler burner front, diesel oil tank of DG set, main lube oil tank,
clean and dirty lube oil tanks.
Medium Velocity Water spray system - cable gallery / Cable spreader room,
Coal conveyors, Transfer points and crusher house, F.O. pumping station and
F.G. tanks
Foam system for Fuel oil tanks.
Portable extinguisher will be provided for Central Control room, Control
equipment room and Computer rooms in the power house building.
Portable and mobile fire extinguishers for entire plant
Fire Tenders (minimum 2 Nos.)
Fire Detection and Alarm system for all Central Control room, Control
Equipment Room, battery rooms, all switchgear rooms / MCC rooms, and
Computer rooms located in Power block area and in other auxiliary buildings.
Necessary instruction and warning plates shall be provided all around
All necessary facemasks, fire jackets, breathing and resuscitation apparatus
and/or ether protection devices for optimal protection for the personnel.
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Hydrant System
The hydrant system consists of a large network of pipe, which will feed
pressurized water, to a number of hydrant outdoor, water monitors and indoor
landing valves with hose reel system. External hydrants will be located all around
the periphery of buildings and internal hydrants will be provided at each landing
floor of staircases through above ground main. Outdoor type fixed water monitors
will be provided for ESP areas and other areas in the coal conveyors at locations
where water cannot reach from hydrant system.
Hose pipes of suitable length fitted with standard accessories like hose coupling,
branch pipes and nozzles will be located in 'HOSE BOXES'.
High Velocity Water Spray (HVWS) System
The spray ring main header will cater water for the spray system. For water spray
system piping network will be separate from the pump house. The HVWS system
will be designed for automatic remote and manual emergency operation for the
Generator Transformers, Unit Aux.
Transformer and Station Transformer and remote manual operation for turbine
lube oil canal pipe lines in main plant, Boiler burner front, and diesel oil Tank of
DG set, main lube oil tank, clean and dirty lube oil tanks.
Medium Velocity Water Spray (MVWS) System
The medium velocity spray system will be provided for the cable gallery /Cable
spreader room, Coal conveyors, Transfer points and crusher house, F.O. pumping
station and F.O. tanks. Water required for this system will be .tapped off from
HVWS/MVWS header.
The fire in the cable gallery / Cable spreader room and coal conveyors will be
detected by a detection system, which will give an electrical signal for the
operation of the deluge valve. In the event of fire in zone, the deluge valve of
corresponding zone and those of adjacent zone on either side will be opened.
The MVWS system for fuel oil pump house will be designed considering the pump
house as a single zone. A network of pipes with spray nozzles will be located near
the roof of the pump house, which will be connected to a deluge valve.
Manual MVWS system will be provided for L.D.O and H.F.O tanks. This system is
provided for LDO and HFO storage tanks. The water for the foam system will be
tapped from the Hydrant system. The system will consist of foam tank, level
indicators, foam ejector, foam makers, fixed piping valves, etc.
Portable and Trolley mounted fire Extinguishers
Fire Extinguishers with suitable capacity, rating and medium such as water, CO2,
foam, Dry Chemical powder (DCP) and with standard accessories and in adequate
numbers as per TAC covering all the buildings in the power plant premises will be
provided.
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Fire Tender
One no. Water Fire Tender as per IS: 950 Type-B.
One no. Foam Tender as per IS-10460.
Fire Water Reservoir
The Plant will be provided with fire water from service I fire water reservoir of
such volume have to satisfy the fire water demand of plant in the worst assumed
scenarios as per TAC requirements. A dedicated storage of 2300m3 of water is
envisaged.
Fire Water Pumps
The fire water pump capacity and head will be designed as per the system
requirement. The fire hydrant system will have dedicated 2 x 100% firewater
main pumps of capacity 410m3/hr, 88MWC.
The main fire pump will be motor driven and one standby diesel engine driven. A
separate fire pumps including with one standby diesel engine driven pump will
serve the HVWS/MVWS system.
The standby pump of Hydrant system will also serve as standby for HVWS/MVWS
system. The entire fire water network will be pressurized and maintained the
hydro-pneumatic tank along with common jockey pumps and air compressors
functions to make up the system leakage losses.
All the main and standby pumps will be capable of operating at 150% flow with a
head drop less than or equal to 65% of the operating head. The shutoff head of
the pump will not be more than 140 % of operating head. Fire pumps will
conform to IS: 5120 and will be certified by TAC as approved Fire pumps.
Diesel Engine drive set
The diesel engine will be of direct injection, multi-cylinder, water cooled, 4-stroke
cycle and will have engine shaft power rating at least fifteen 15 % higher than the
maximum power required at the pump shaft at rated speed.
As the fire pumping unit is not required to run continuously for long period and
operation will not be very frequent, special features will be built into the engine to
allow it to start instantaneously against full load; even it has remained idle for
long period.
The engine will be able to start quickly from cold condition. The starting system
will include a DC motor having high starting torque to overcome full engine
compression. The engine will be provided with two sets of 24 volts heavy duty
VRL and lead acid batteries.
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The diesel engine will have provision to start on auto / manual mode. The selector
switch for the same will be provided in the control panel. The cooling water
system for the diesel engine will be provided as per TAC requirement. The fuel
storage tank will be provided as per the TAC requirement.
Fire Detection and Alarm System
Fire detection and alarm system provided for the entire plant area will be
microprocessor based Intelligent Analog Addressable type. The system will consist
of central monitoring station located in unit control room will be provided.
The main fire alarm panel will be provided in the unit control room, one fire alarm
and control panel in coal handling plant control room and repeater panel, which
will be provided hi the fire station office.
2.10 Miscellaneous Auxiliaries
2.10.1 Cranes, Hoists & Elevators
Electric Overhead Traveling (EOT) cranes will be provided in Steam Turbine hall,
raw water and firewater pump house, workshop, DG plant building etc. The
cranes will be used for unloading of heavy equipment and also for erection and
maintenance of equipment. The cranes will be designed to handle the heaviest
piece in that area during maintenance.
Monorail hosts of suitable capacity will be installed in the following areas.
Fuel oil pump house
DM plant
Chlorination Plant
Air heater
ID fan & FD fan area
Mills area
Air compressor house / building
Ash water pump house
Ash recycle water pump house
Stores
One goods cum passenger elevator of about 2000 kg carrying capacity will be
provided for boiler house and one goods cum passenger elevator of about 1000
kg carrying capacity will be provided for power house building. One passenger
elevator of about 550 kg carrying capacity will be provided for the administrative
building. One number of rack and pinion lift for chimney will be provided for
handling passenger / goods.
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2.10.2 Associated Facilities
Repair Workshop
For achieving higher availability of the plant some of the plant maintenance would
have to be done at site following concept of unit exchange system for repair and
maintenance.
Under this system, the defective components would be replaced immediately by
sound ones from the stores. Some of the defective components would thereafter
be repaired in the site workshop and sent back to the stores. Following this
System two types of activities namely maintenance and reconditioning would be
physically separated thereby.
Speeding-up maintenance activity
In order to carry out the repair activities, it is proposed to provide the following
shops
a. Main workshop
b. Instrument repair shop
c. A repair shop for mobile equipment to be located near the coal storage yard
d. Loco engine repair shade
e. Motor vehicle repair shops
Besides tools, tackle, gadgets, measuring instruments, testing equipment as
required would be procured.
2.10.3 General Stores
Both covered and open space would be required for storage of various material
and equipment required for construction as well as operation and maintenance of
the plant. While the construction stores would be temporary, the other stores
would be permanent. Stores would broadly have the following divisions to house
equipment and material of different categories
Chemical Laboratory & Testing Facilities
A fully equipped chemical laboratory adequate to carry out the tests and analyses
required for the station would be provided in the Service Building of the station.
The testing and calibration laboratories for Control &Instrumentation (C&I) and
Relay-Metering instruments would also be housed in the same building.
Necessary facilities including standard instruments for analyses or tests or
calibrations of various items would be provided.
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Chapter – 2
Project Description
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2.11 Sources of Pollution and Mitigation Measures
The various types of pollution from a thermal power power plant are categorized
under the following types:
a) Air pollution
b) Water pollution
c) Sewage disposal
d) Thermal pollution
e) Noise pollution
f) Pollution monitoring and surveillance systems
Coal based thermal power plants are a major source of gaseous emissions. In
addition, wastewater and solid waste will also be generated. The quantities and
the composition of the gaseous, liquid and solid waste that are generated in a
thermal power plant will be managed and treated such that their final disposal
into the environment meets all the statutory requirements and the environmental
impacts are mitigated.
2.11.1 Air Pollution Sources and Mitigation Measures
The Air pollutants from the power plant are:
a) Dust particulates from fly ash in flue gas
b) Sulphur dioxide in flue gas
c) Nitrogen oxides in flue gas
d) Particulate Matter (PM)
e) Coal dust particles during storage/handling
The Indian Emission Regulations stipulate the limits for particulate matter
emission for thermal power stations. The minimum stack height to be maintained
to keep the Sulphur dioxide level in the ambient within the air quality standards.
The stack height for the 60 MW & 135 units under consideration will be 145
metres (common stack). For the Independent 1 x 350 MW unit, separate stack
(220 m) will be erected considering fuel characteristics.
The dust content in the flue gas will be limited to 50 mg/Nm3 even with one of
the fields of ESP is not in working condition.
Providing specially designed burners reduce NOx emission from the steam
generator. The maximum NOx emission from the unit will be as per the
CPCB/SPCB norms by using low NOx burners in the firing system of the steam
generator. As noted above, PM, SO2 and NOx emission levels will meet the
requirement of Indian Central Pollution Control Board (CPCB). For coal dust control, water spraying arrangement will be provided to spray water
into each wagon prior to discharge. Dust generated at the wagon discharge points
will be further suppressed by spraying chemical solution.
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Crusher houses, junction towers, feed points below wagon discharge and
emergency reclaim hoppers will be provided with wet scrubber type dust
extraction system. Sprinklers will be provided all around the stockpile to suppress
the dust generation and to wet the coal while compacting to minimize the dust
nuisance.
The expected air emissions are given in Table–2.12.
TABLE – 2.12
STACK MONITORING DATA
Particulars Stack #1 Stack #2
Material of Construction RCC RCC
Stack attached to 1 x 60 MW &
1 x 135 MW
1 x 350 MW
Stack height (m) 145 220
Stack diameter (mm) approx. 5250 6500
Volume Flow Rate (m3/s) 475.45 696.82
Velocity of flue gas (m/s) 22.0 21.0
Temperature of flue gas (°C) 140 140
Flue gas specific volume (kg/Nm³) 1.3 1.3
Fuel Consumption (kg/s) 34.17 55.09
Sulphur content (% w/w) 0.5 0.5
Emission rate – NOx (g/s) 307.5 495.83
Emission rate – SO2 (g/s) 341.67 550.925
Emission rate – PM (g/s) 21.5 34.841
2.11.1.2 Mitigation Measures
The mitigation measures proposed for the TPP are detailed below:
145 m & 220 m tall stacks for flue gas emission
Space provision for retrofitting FGD (Flue Gas Desulfurization) systems
High efficiency ESPs to reduce PM level in the exhaust gas to < 50 mg/Nm³
Dust suppression and extraction system at handling plant area to control
fugitive emission
Greenbelt development in the plant and ash disposal areas
A minimum water depth will be maintained in the ash dyke to prevent fugitive
dust emission
Use of bag filters at all transfer points
Use of limestone to limit SO2 emission
High efficiency Electro Static Precipitator of 99.9% are provided for limiting
PM concentration in the flue gas to less than 50 mg/Nm³. The tall stack of 145
m & 220 m height based on maximum SO2 concentration in the flue gas is
provided for natural dispersion at high elevation so that ground level
concentration are within acceptable limits
The emission of NOx, is reduced by burning fuel at a lower temperature and
shortening the throughput time of the fuel
NOx is also controlled by operating at low excess air
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2.11.1.3 Fugitive Emissions
All other dust sources are considered as secondary sources since they are not
process implied. These dust sources may occur wherever relatively dry or dusty
material is handled, conveyed, pumped or extracted. Water spray is being carried
out to control fugitive dust due to wind. All the materials will be stored in a
covered storage facilities.
2.11.2 Wastewater Generation and Mitigation Measures
Steam generator blow down
The salient characteristics of the blow down water from the point of view of
pollution are the pH and temperature of water since suspended solids are
negligible. The pH will be in the range of 9.5 to 10.3 and the temperature of the
blow down water will be about 100°C since it is flashed in an atmospheric flash
tank (IBD tank). It is proposed to lead steam generator blow down to cooling
tanks and then sequentially to guard pond. The retained water will be RO treated
to meet the CPCB norms and will be reused for boiler make-up.
DM Plant Effluents
Hydrochloric acid and caustic soda will be used as regenerants in the DM plant.
The acid and alkali effluents during the regeneration process of the ion
exchangers will be drained into an underground neutralizing pit. The effluent will
be neutralized by the addition of either acid or alkali to achieve the required pH.
The effluent will then be pumped to RO plant and reused for process.
Effluent Disposal
The following high TDS effluents water will be collected in a guard pond.
Pressure sand filter back wash (TDS < 100)
Effluent discharge from Neutralizing pit (TDS < 6000)
Sewage Disposal
Sewage from various buildings in power plant area will be conveyed through
separate drains to septic tanks. The effluent from septic tank will be disposed in
soil by providing dispersion trenches. There will be no ground pollution because of
leaching. Sludge will be removed occasionally and will be disposed of as land fill
at suitable places.
The waste water generated from proposed project is given in Table-2.13.
Rapid Environmental Impact Assessment for the proposed augmentation
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TABLE-2.13
WASTE WATER GENERATION FROM THE POWER PLANT
Sr. No. Units
Water
Requirement (KLD)
Loses/ Uses
Waste
Water Generated
Usage/ Disposal
1 Boiler Makeup 193 20 173 Reuse for process
2 Potable Water 16 3.2 12.8 Greenbelt
maintenance
3 DM Plant 31 0 31 Reuse for process
Total 240 23.2 216.8
The total wastewater generated from the plant after the proposed expansion will be
216.8 KLD. Boiler blow down (173.0 KLD) & DM plant regeneration wastewater
(31.0 KLD) generated after the proposed expansion will be treated in 2-stage RO
plant. Available treated effluent (160.16 KLD) will be re-used in the process. RO
reject (43.84 KLD) will be used for ash quenching & coal dust suppression.
Domestic sewage (12.8 KLD) will be treated in the existing sewage treatment
plant itself. Treated domestic sewage will be utilized for greenbelt maintenance.
Thus, the plant will operate on zero liquid discharge concept even after the
proposed expansion.
2.11.3 Solid Waste Generation and Mitigation Measures
Ash is the main solid waste generated in the coal based thermal power plant.
Major portion of the ash will be utilized by supplying to potential users. Efforts will
be made to utilize 100% fly ash as per the Fly Ash Notification, 1999 and as
amended later.
The ash which is not lifted by the potential users will be disposed of in the ash
dyke using High Concentration Slurry Disposal (HCSD) method. In this method of
ash disposal, the slurry is highly viscous and non-Newtonian fluid requiring less
water compared to conventional low concentration slurry disposal. The ash dyke
will be provided with trenches to collect the storm water during rainy days.
Greenbelt will be provided enveloping the ash dyke to arrest the fugitive dust
emissions. Ash dyke will also be provided with HDPE liner to prevent leaching of
contaminants to groundwater. The quantities of solid waste expected the plant is
given in Table – 2.14.
Rapid Environmental Impact Assessment for the proposed augmentation
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TABLE – 2.14
SOLID WASTE GENERATION AND DISPOSAL
Sr.
No. Power Generation
Ash generation
Mode of
Disposal Existing
(TPD)
Upon
expansion
(TPD)
1. 1 x 60 MW 50 50 Sold to Cement
manufacturers 2. 1 x 135 MW -- 116
3. 1 x 350 MW -- 285
Total 50 451
Capacity of fly ash silo: 791 m3
Capacity of bottom ash silo: 216 m3
2.11.4 Noise Pollution and Mitigation Measures
The major noise generating sources in the power plant are boiler, coal crushing,
material handling area, and water pumps. The noise levels at 1 m away from these
sources will be maintained at less than 85-dB (A) in compliance with the statutory
requirements. All equipment in the power plant will be designed/operated to have
a noise level not exceeding 85 to 90 dB(A) as per the requirement of
Occupational Safety and Health Administration Standard (OSHA). As per this
standard, protection from noise is required when sound levels exceed those in
given below when measured on the A scale at slow response on a standard sound
level meter.
TABLE – 2.15
NOISE LEVEL EXPOSURE LIMITS
Duration per day (hrs.) Sound level in dB(A)
8 90
6 92
4 95
3 97
2 100
1.5 102
1 105
0.5 110
0.25 115
In general, the following measures will be adopted for noise pollution control.
Technical measures
Administrative measures
Personal protection measures
Rapid Environmental Impact Assessment for the proposed augmentation
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In thermal power plants high pressure boilers, exhausters, turbines and leaking
air/ steam pipelines are the primary sources of noise pollution. The following
technical measures will be taken to overcome these noises.
Continuous vigilance in high pressure air/steam pipelines for leakages and
once noticed, immediate plugging of the leakage reduces plugging them, thus
reducing the noise at the source.
Providing acoustic enclosures / barriers for the turbines.
Providing silencers at inlet / outlet of the high pressure equipment like DG set,
compressors, fans etc.,
Regular checking of vibration level of high speed machines and taking
necessary steps to mitigate the same. In areas such as turbine floor,
compressed air station and pump houses, soundproof enclosures will be
provided for the operators.
In the boiler plant, there are various noise polluting sources such as boilers and
high pressure pipelines where technical measures will not be practically effective.
In such cases, the following administrative measures are proposed.
Workers will be assigned rotational duties to minimize noise exposure time.
Medical check-up of all workers will be done at regular interval for any noise
related health problems and if any such problem is detected they will be
assigned alternative duty.
Besides all the above measures all workers exposed to high noise will be provided
with personal protective devices such as ear plugs and ear muffs. Workers will be
educated about the benefits of the protective devices and encouraged to use
them.
2.12 Environmental Laboratory
To evaluate the physico-chemico properties of source emission /waste water
discharge and to establish the ambient pollution level during power plant
operation, as desired by the Ministry of Environment, Forest & Climate Change
(MoEFCC), New Delhi, and State Pollution Control Board (SPCB), an
environmental laboratory has been considered for monitoring/ testing of different
pollutants, Gas, liquid & solids, generated from the plant. List of
equipment/instrument pertaining to Environmental pollution monitoring will be
provided during detailed engineering.
Rapid Environmental Impact Assessment for the proposed augmentation &
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Chapter – 3
Description of the environment
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3.0 DESCRIPTION OF THE ENVIRONMENT
3.1 Introduction
This chapter illustrates the description of the existing environmental status of the
study area with reference to the prominent environmental attributes. As per the
EIA guidelines, the study area has been divided into core zone and buffer zone
which is about 10 km radius from the boundary of the existing & the proposed
site.
The existing environmental setting is considered to adjudge the baseline
environmental conditions, which are described with respect to climate, hydro-
geological aspects, atmospheric conditions, water quality, soil quality, vegetation
pattern, ecology and socio-economic profiles of people and land use. The
objective of this section is to define the present environmental status, which
would help in assessing the environmental impacts due to the proposed
expansion activities.
This report incorporates the baseline data generated through primary surveys for
three months from 1st May 2014 to 31st July 2014 representing pre-monsoon
season.
3.2 Methodology
Appropriate methodologies have been followed in developing the EIA/EMP report.
The methodology adopted for the study is outlined below:
Conducting reconnaissance surveys for knowing the study area; and
Selecting sampling locations for conducting various environment baseline
studies.
The sampling locations have been selected on the basis of the following:
Predominant wind directions recorded by the India Meteorological Department
(IMD) Meenambakkam, Chennai observatory;
Existing topography;
Drainage pattern and location of existing surface water bodies like
lakes/ponds, rivers and streams;
Location of villages/towns/sensitive areas; and
Areas, which represent baseline conditions.
The field observations have been used to:
Assess the positive and negative impacts due to the proposed expansion
activity; and
Suggest appropriate mitigation measures for negating the adverse
environmental impacts, if any; and
Suggesting post-project monitoring requirements and suitable mechanism for it.
Rapid Environmental Impact Assessment for the proposed augmentation &
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Description of the environment
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3.3 Geology & hydrogeology
Central Ground Water Board (CGWB) has carried out extensive geological and
hydro-geological surveys for the Thiruvallur district.
3.3.1 Administrative Details
Tiruvallur district is having administrative divisions of 8 taluks, 14 blocks, 539
Panchayats and 805 villages.
3.3.2 Basin and sub-basin
The district is part of the composite east flowing river basin having Araniar-
Korataliar and Cooum sub basins.
3.3.3 Drainage
Araniyar, Korattalayar, Cooum, Nagari and Nandhi are the important rivers. The
drainage pattern, in general, is dendritic. All the rivers are seasonal and carry
substantial flows during monsoon period. Korattaliar river water is supplied to
Cholavaram and Red Hill tanks by constructing an Anicut at Vellore
Tambarambakkam. After filling a number of tanks on its further course, the river
empties into the Ennore creek a few kilometres north of Chennai. The Cooum
river, flowing across the southern part of the district, has its origin in the surplus
waters of the Cooum tank in Tiruvallur taluk and also receives the surplus waters
of a number of tanks. It feeds the Chembarambakkam tank through a channel. It
finally drains into the Bay of Bengal.
The chief irrigation sources in the area are the tanks, wells and tube wells. Canal
irrigation is highest in Minjur block followed by Sholavaram, Pallipattu, R.K.Pet,
Poondi, Gummidipoondi and Ellapuram blocks.
3.3.4 Rainfall and climate
The district receives the rain under the influence of both southwest and northeast
monsoons. Most of the precipitation occurs in the form of cyclonic storms caused
due to the depressions in Bay of Bengal chiefly during Northeast monsoon period.
The southwest monsoon rainfall is highly erratic and summer rains are negligible.
Rainfall data analysis shows that the normal annual rainfall varies from 950mm
to 1150mm. It is minimum around Chengam (982.1mm) in the south eastern
part of the district. It gradually increases towards west and a maximum around
Wandavasi (1117.1mm) is noticed.
The district enjoys a tropical climate. The period from April to June is generally
hot and dry. The weather is pleasant during the period from November to
January. Usually mornings are more humid than afternoons. The relative
humidity varies between 65 and 85% in the mornings while in the afternoon it
varies between 40 and 70%.
The annual mean minimum and maximum temperature are 24.3 ° and 32.9°C
respectively. The day time heat is oppressive and the temperature is as high as
41.2°C. The lowest temperature recorded is of the order of 18.1 °C.
Rapid Environmental Impact Assessment for the proposed augmentation &
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Description of the environment
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3.3.5 Geomorphology and soil types
The prominent geomorphic units identified in the district through interpretation of
Satellite imagery are 1) Alluvial Plain, 2) Old River Courses 3) Coastal plains 4)
Shallow & deep buried Pediments, 5) Pediments and 6) Structural Hills.
The elevation of the area ranges from 183 m AMSL in the west to sea level in the
east. Four cycles of erosion gave rise to a complex assemblage of fluvial,
estuarine and marine deposits. The major part of the area is characterized by an
undulating topography with innumerable depressions which are used as irrigation
tanks.
The coastal tract is marked by three beach terraces with broad inter-terrace
depressions. The coastal plains display a fairly lower level or gently rolling surface
and only slightly elevated above the local water surfaces or rivers. The straight
trend of the coastal tract is resultant of development of vast alluvial plains. There
are a number of dunes in the coastal tract.
3.3.6 Soil
Soil in the area have been classified into i) Red soil ii) Black soil iii) Alluvial soil
iv) colluvial soil. The major part is covered by Red soil of red sandy/clay loam
type. Ferrugineous red soils are also seen at places. Black soils are deep to very
deep and generally occur in the depressions adjacent to hilly areas, in the
western part. Alluvial soils occur along the river courses and eastern part of the
coastal areas. Sandy coastal alluvium (arenaceous soil) are seen all along the sea
coast as a narrow belt.
3.3.7 Ground water scenario
Hydrogeology
The district is underlain by both porous and fissured formations. The important
aquifer systems in the district are constituted by i) unconsolidated & semi-
consolidated formations and ii) weathered, fissured and fractured crystalline
rocks.
The porous formations in the district include sandstones and clays of Jurassic age
(Upper Gondwana), marine sediments of Cretaceous age, Sandstones of Tertiary
age and Recent alluvial formations. As the Gondwana formations are well-
compacted and poorly jointed, the movement of ground water in these
formations is mostly restricted to shallow levels. Ground water occurs under
phreatic to semi-confined conditions in the inter-granular pore spaces in sands
and sandstones and the bedding planes and thin fractures in shales. In the area
underlain by Cretaceous sediments, ground water development is rather poor due
to the rugged nature of the terrain and the poor quality of the formation water.
Quaternary formations comprising mainly sands, clays and gravels are confined
to major drainage courses in the district. The maximum thickness of alluvium is
30.0 m. whereas the average thickness is about 15.0 m.
Rapid Environmental Impact Assessment for the proposed augmentation &
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Ground water occurs under phreatic to semi-confined conditions in these
formations and is being developed by means of dug wells and filter points.
Alluvium, which forms a good aquifer system along the Araniyar and Korattalaiyar
river bed, is one of the major sources of water supply to the urban areas of
Chennai city and also the industrial units.
Ground water generally occurs under phreatic conditions in the weathered mantle
and under semi-confined conditions in the fissured and fractured zones at deeper
levels. The thickness of weathered zone in the district is in the range of 2 to 12
m. The depth of the wells ranged from 8.00 to 15.00 m bgl.
The yield of large diameter wells tapping the weathered mantle of crystalline
rocks ranges from 100 to 500 lpm and are able to sustain pumping for 2 to 6
hours per day.
The yield of bore wells drilled down to a depth of 50 to 60 m ranges from 20 to
400 lpm. The yield of successful bore wells drilled down to a depth of 150 m bgl
during the ground water exploration programme of Central Ground Water Board
ranged from 1.2 to 7.6 lpm.
The depth to water level in the district varied between 2.38 - 7.36 m bgl during
pre-monsoon (May 2006) and 0.79 - 5.30 m bgl during post monsoon (Jan
2007). The seasonal fluctuation shows a rise between 0.28 and 4.80 m bgl. The
piezometric head varied between 2.20 to 10.30 m bgl (May 2006) during pre-
monsoon and 2.72 to 8.55 m bgl during post monsoon.
Ground water resources
The ground water resources have been computed jointly by Central Ground
Water Board and State Ground & Surface Water Resources and Development
Centre (PWD, WRO, Government of Tamil Nadu) as on 31st March 2004. The
salient features of the computations are furnished in Table-3.1.
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TABLE-3.1
GROUND WATER RESOURCES
Block
Net
Groundwater
Availability (M.Cu.m)
Existing
Gross
Draft for Irrigation
(M.Cu.m)
Existing
Gross Draft
for
Domestic
and industrial
water
supply
(M.Cu.m)
Existing
Gross
Draft for all uses
(M.Cu.m)
Allocation for
Domestic and
Industrial
Requirement
supply upto next 25 years
(2029)
(M.Cu.m)
Net
groundwatre
Availability for
future Irriation
Development
(M.Cu.m)
Stage of
Groundwater
Development (%)
Category of
Block
Ellapuram 114.68 157.14 3.30 160.44 3.49 -45.95 140 Over
Exploited
Gummudipoondi 169.05 82.66 4.16 86.82 4.40 81.99 51 Safe
Kadambathur 88.03 79.02 2.86 81.88 3.03 5.98 93 Critical
Madhavaram 31.39 14.49 3.04 17.53 3.22 13.68 56 Safe
Minjur 111.35 113.36 35.71 149.07 35.87 -37.88 134 Over
Exploited
Pallipattu 46.93 71.27 2.51 73.78 2.66 -26.99 157 Over
Exploited
Poonamalee 64.81 55.43 4.85 60.27 5.13 4.25 93 Critical
Poondi 115.04 77.75 2.55 80.30 2.70 34.59 70 Safe
R.K.Pet 55.49 67.83 2.46 70.29 2.60 -14.95 127 Over
Exploited
Sholavaram 88.56 67.62 3.30 70.92 3.49 17.46 80 Semi
Critical
Thiruvalankadu 71.42 74.09 2.33 76.43 2.47 -5.15 107 Over
Exploited
Tiruttani 32.97 42.56 2.67 45.23 2.83 -12.41 137 Over
Exploited
Tiruvallur 70.16 51.72 2.75 54.47 2.91 15.54 78 Semi
Critical
Villivakkam 54.59 26.76 4.27 31.02 4.52 23.31 57 Safe
District Total 1114.46 981.69 76.76 1058.46 79.31 53.46 95 --
Ground water in phreatic aquifers in Tiruvallur district, in general, is colourless,
odourless and slightly alkaline in nature. The specific electrical conductance of
ground water in phreatic zone (in MicroSeimens at 25o C) during May 2006 was
in the range of 480 to 2360 in the district. It is between 750 and 2250 µS/cm at
25oC in the major part of the district. Conductance below 750 µS/cm have been
observed in ground water in parts of Gummidipundi, Minjur, Sholavaram and
Puzhal blocks, whereas conductance exceeding 2250 µS/cm have been observed
in part of Tiruvelangadu block.
It is observed that the ground water is suitable for drinking and domestic uses in
respect of all the constituents except total hardness and Nitrate in more than 90
percent of samples analysed.
Total Hardness as CaCO3 is observed to be in excess of permissible limits in about
36 percent of samples analysed whereas Nitrate is found in excess of 45 mg/l in
about 32 percent samples. The incidence of high total hardness is attributed to
the composition of lithounits constituting the aquifers in the district, whereas the
Nitrate pollution is most likely due to the use of pesticides and fertilizers for
agriculture. With regard to irrigation suitability based on specific electrical
conductance and Sodium Adsorption Ratio (SAR), it is observed that ground
water in the phreatic zone may cause high to very high salinity hazard and
medium to high alkali hazard when used for irrigation. Proper soil management
strategies are to be adopted in the major part of the district while using ground
water for irrigation.
Rapid Environmental Impact Assessment for the proposed augmentation &
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Chapter – 3
Description of the environment
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Status of Ground Water Development
The estimation of groundwater resources for the district has shown that 6 blocks
are over exploited and 2 blocks are under “critical” category. The shallow alluvial
aquifers along Korattalaiyar and Araniyar rivers serve as an important source of
drinking water for Chennai Metropolitan area and 5 well fields have been
constructed in Tiruvallur district for the purpose. The well fields have a combined
yield of 36.50 MCM/year.
Dug wells are the most common ground water abstraction structures used for
irrigation in the district. The yield of dug wells range from < 50 to 200 m3/day in
weathered crystalline rocks, 20 to 100 m3/day in Gondwana formations and upto
400 m3/day in Recent alluvial formations along major drainage courses. The dug
wells in hard rock terrain tapping the entire weathered residuum are capable of
yielding 6 - 7 lps, requiring the installation of 5 HP centrifugal pumps for
extraction of ground water.
Rapid Environmental Impact Assessment for the proposed augmentation & expansion of existing thermal power plant at Gummidipoondi, Thiruvallur district, Tamilnadu
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Description of the environment
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FIGURE-3.1
HYDROGEOLOGY OF THIRUVALLUR DISTRICT
ANDHRA PRADESH
VELLORE
KANCHIPURAM
GUMMIDIPOONDI
UTHUKOTTAI
MINJUR
SHOLAVARAM
THIRUVALLUR
VILLIVAKKAM
POONAMALEE
POONDI
THIRUVILANGADU
THIRUTTANI
PALLIPATTU
RK PET
CHENNAI
BA
Y O
F B
EN
GA
L
Rapid Environmental Impact Assessment for the proposed augmentation &
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Chapter – 3
Description of the environment
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3.4 Land Use Studies
Studies on land use aspects of eco-system play an important role in identifying
sensitive issues and taking appropriate actions by maintaining ‘Ecological
Homeostasis’ for development of the region.
3.4.1 Objectives
The objectives of land use studies are:
To determine the existing land use pattern in the study area;
To analyze the impacts on land use in the study area; and
To give recommendations for optimizing the future land use pattern vis-a-vis
proposed expansion activity in the study area and its associated impacts.
3.4.2 Methodology
The land use pattern of the study area has been studied by analyzing the available
secondary data such as the District Primary Census Handbook of Thiruvallur
District.
The land use is classified into four types - viz. forests, area under cultivation,
cultivable waste and the area not available for cultivation. The land under
cultivation is further sub-divided into two types viz. irrigated and un-irrigated.
3.4.3 Land Use Pattern in Study Area Based on Satellite imagery
Methodology
Information of land use and land cover is important for many planning and
management activities concerning the surface of the earth (Agarwal and Garg,
2000). Land use refers to man's activities on land, which are directly related to
land (Anderson et al., 1976). The land use and the land cover determine the
infiltration capacity. Barren surfaces are poor retainers of water as compared to
grasslands and forests, which not only hold water for longer periods on the
surface, but at the same time allow it to percolate down.
The terms ‘land use’ and ‘land cover’ (LULC) are often used to describe maps that
provide information about the types of features found on the earth’s surface (land
cover) and the human activity that is associated with them (land use). These are
important parameters for number of environmental related development projects
associated with inland and coastal areas. It is necessary to have information on
existing land use / land cover but also the capability to monitor the dynamics of
land use resulting out of changing demands. Satellite remote sensing is being
used for determining different types of land use classes as it provides a means of
assessing a large area with limited time and resources. However satellite images
do not record land cover details directly and they are measured based on the
solar energy reflected from each area on the land.
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The amount of multi spectral energy in multi wavelengths depends on the type of
material at the earth’s surface and the objective is to associate particular land
cover with each of these reflected energies, which is achieved using either visual
or digital interpretation. In the present study the task is to study in detail the
land use and land cover in and around the project site respect to the
development of the plant. The study envisages different LULC around the plant
area and the procedure adopted is as below. Remote sensing satellite imageries
were collected and interpreted for the 10-km radius study area for analyzing the
Land use pattern of the study area. Based on the satellite data, Land use/ Land
cover maps have been prepared.
Scale of mapping
Considering the user defined scale of mapping, 1:50000 IRS-P6, LISS-III data on
1:50000 scale was used for Land use / Land cover mapping of 10 km radius for
proposed expansion activity. The description of the land use categories for 10 km
radius and the statistics are given for core and buffer zones separately.
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FIGURE – 3.2
FLOW CHART SHOWING METHODOLOGY OF LANDUSE MAPPING
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Interpretation Technique
Standard on screen visual interpretation procedure was followed. The various
Land use / Land cover classes interpreted along with the SOI topographical maps
during the initial rapid reconnaissance of the study area. The physiognomic
expressions conceived by image elements of color, tone, texture, size, shape,
pattern, shadow, location and associated features are used to interpret the FCC
imagery. Image interpretation keys were developed for each of the LU/LC classes
in terms of image elements.
March 2009 FCC imagery (Digital data) of the study area was interpreted for the
relevant land use classes. On screen visual interpretation coupled with supervised
image classification techniques are used to prepare the land use classification.
i. Digitisation of the study area (10 km radius from the plant site) from the topo
maps
ii. Satellite Data Selection: In the present study the IRS –P6 satellite image with
path row 102-64 for the topo map of 57P-7. have been procured and
interpreted using the ERDAS imaging software adopting the necessary
interpretation techniques.
iii. Satellite data interpretation and vectorisation of the resulting units
iv. Adopting the available guidelines from manual of LULC mapping using
Satellite imagery (NRSA, 1989)
v. Field checking and ground truth validation
vi. Composition of final LULC map
The LULC Classification has been done at three levels where level -1 being the
broad classification about the land covers that is Built-up land, agriculture land,
waste land, wet lands, and water bodies. These are followed by level –II where
built-up land is divided into towns/cities as well villages. The Agriculture land is
divided into different classes such as cropland, Fallow, Plantation, while
wastelands are broadly divided into, Land with scrub and without Scrub and
Mining and Industrial wasteland. The wetlands are classified into inland wetlands,
coastal wetlands and islands. The water bodies are classified further into
River/stream, Canal, Tanks and bay. In the present study level II classification
has been undertaken. The satellite imagery of 10 km radius from the project site
is presented in Figure-3.3.
Field Verification
Field verification involved collection, verification and record of the different
surface features that create specific spectral signatures / image expressions on
FCC. In the study area, doubtful areas identified in course of interpretation of
imagery is systematically listed and transferred on to the corresponding SOI
topographical maps for ground verification. In addition to these, traverse routes
were planned with reference to SOI topographical maps to verify interpreted
LU/LC classes in such a manner that all the different classes are covered by at
least 5 sampling areas, evenly distributed in the area.
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FIGURE – 3.3
SATELLITE IMAGERY OF THE STUDY AREA
PROPOSED AUGMENTATION &
EXPANSION OF EXISTING THERMAL
POWER PLANT AT GUMMIDIPOONDI, THIRUVALLUR DISTRICT,
TAMILNADU
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Ground truth details involving LU/LC classes and other ancillary information about
crop growth stage, exposed soils, landform, nature and type of land degradation
are recorded and the different land use classes are taken.
Description of the land use / land cover classes
Built-up land
It is defined as an area of human settlements composed of houses, commercial
complex, transport, communication lines, utilities, services, places of worships,
recreational areas, industries etc. Depending upon the nature and type of utilities
and size of habitations, residential areas can be aggregated into villages, towns
and cities. All the man-made construction covering land belongs to this category.
Agricultural land
This category includes the land utilized for crops, vegetables, fodder and fruits.
Existing cropland and current fallows are included in this category.
It is described as an area under agricultural tree crops, planted adopting certain
agricultural management techniques.
Wasteland
Wastelands are the degraded or under-utilized lands most of which could be
brought under productive use with proper soil and water management practices.
Wasteland results from various environmental and human factors.
Land with or without Scrub
The land, which is outside the forest boundary and not utilized for cultivation.
Land with or without scrub usually associated with shallow, stony, rocky
otherwise non-arable lands.
Water bodies
The category comprises area of surface water, either impounded in the form of
ponds, reservoirs or flowing as streams, rivers and canals. River cater channel is
inland waterways used for irrigation and for flood control.
The land use map of the study area based on satellite imagery is presented in
Figure-3.4.
The land use analyses show that the area is of predominantly Plantation followed
by Crop land in the core and buffer zones of the study area. It is noticed since
there is no industrial development in and around the project site, there may not
have any direct impact on the existing land use and soil. However, it is generally
agreed that as the total volume of transport activity may increase due to the
development leading to negative externalities like pollution and congestion. Some
environmental damage may be acceptable if transport activity generates positive
net benefits to society.
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FIGURE – 3.4
LANDUSE OF THE STUDY AREA
PROPOSED AUGMENTATION & EXPANSION OF EXISTING THERMAL POWER PLANT AT
GUMMIDIPOONDI, THIRUVALLUR DISTRICT, TAMILNADU
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3.5 Meteorology
The meteorological data recorded during the monitoring period is very useful for
proper interpretation of the baseline information as well as for input prediction
models for air quality dispersion. Historical data on meteorological parameters will
also play an important role in identifying the general meteorological regime of the
region.
The year may broadly be divided into four seasons:
Winter season : December to February
Pre-monsoon season : March to May
Monsoon season : June to September
Post-monsoon season : October to November
3.5.1 Methodology
The methodology adopted for monitoring surface observations is as per the
standard norms laid down by Bureau of Indian Standards (IS:8829) and India
Meteorological Department (IMD). On-site monitoring was undertaken for various
meteorological variables in order to generate the site-specific data. The generated
data is then compared with the meteorological data generated by IMD.
Methodology of Data Generation
The automatic meteorological instrument was installed on top of the admin
building at the plant premises to record wind speed, direction, relative humidity
and temperature. Cloud cover is recorded by visual observation. Rainfall is
monitored by rain gauge. Hourly average, maximum, and minimum values of
wind speed, direction, temperature, relative humidity and rainfall have been
recorded continuously at this station.
Continuous recording meteorological instrument [Make: Dynalab, Pune (Model
No.WDL1002] has been used for recording the met data. The sensitivity of the
equipment is given in Table-3.2.
TABLE-3.2
SENSITIVITY OF METEOROLOGY MONITORING EQUIPMENT
Sr. No. Sensor Sensitivity
1 Wind Speed Sensor ± 0.02 m/s
2 Wind Direction Sensor ± 3 degrees
3 Temperature Sensor ± 0.2oC
Sources of Information
Secondary information on meteorological conditions has been collected from the
nearest IMD station at Chennai Airport.
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India Meteorological Department has been monitoring surface observations at
Chennai since 1891. Pressure, temperature, relative humidity, rainfall, wind
speed and direction are measured twice a day viz., at 0830 and 1730 hr. The
wind speed and direction data of IMD, Chennai has been obtained for the past
available 10 years. The data for the remaining parameters has been collected for
the last 10 years and processed.
3.5.2 Synthesis of Data on Climatic Conditions
Analysis of the data Recorded at IMD – Chennai
Temperature
The winter season starts from January and continues till the end of February.
January is the coldest month with the mean daily maximum temperature at 33.3°C
with the mean daily minimum temperature at 17.0°C. Both the day and night
temperatures increase rapidly during the onset of Pre-monsoon season. During Pre-
monsoon the mean maximum temperature (May) is observed at 43.4°C with the
mean minimum temperature at 21.6°C. The mean maximum temperature in the
Monsoon season was observed to be 42.8°C whereas the mean minimum
temperature was observed to be 21.2°C. By end of September with the onset of
Northeast monsoon (October), day temperatures decrease slightly with the mean
maximum temperature at 35.9°C with the mean minimum temperature at 22.4°C.
The monthly variations of temperatures are presented in Table-3.3.
Relative Humidity
The air is generally very humid in the region especially during monsoon when the
average relative humidity is observed around 67% with a maximum and minimum
of 100% and 35% respectively. In the pre-monsoon period the relative humidity is
63%. During the pre-monsoon season the mean maximum humidity is observed at
100%, with the mean minimum humidity at 39% in the month of May and April
respectively. During winter season the humidity is found to be in line with the values
recorded during the Pre-monsoon season. The mean maximum humidity recorded
during winter season, which is the driest part of year with an average of 66%
relative humidity. The mean maximum relative humidity is observed to be 100%
with mean minimum humidity at 38%. The monthly mean variations in relative
humidity are presented in Table-3.3.
Atmospheric Pressure
The station level maximum and minimum atmospheric pressure levels are recorded
during the winter and monsoon seasons. The maximum pressure observed is in the
range of 1016.5 to 1003.5-mb, with the maximum pressure (1016.5-Mb) occurring
during the winter season, in the month of January. The minimum pressure observed
is in the range of 1013.6 to 999.9 Mb, with the minimum pressure (999.9-Mb)
occurring during the pre-monsoon season in the month of June. The average
pressure levels in all other months are found to be in the range of 1008.5 to
1010.6-mb. The monthly variations in the pressure levels are presented in Table-
3.3.
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Rainfall
It is observed that the north-east monsoon is more predominant than the south-
west monsoon. The southwest monsoon generally sets in during the last week of
May. About 30% of the rainfall is received during the southwest monsoon. The
rainfall gradually increases after September (and reaches maximum rainfall is
recorded in the month of November). The area experiences maximum rainfall
(308.0 mm) in the month of November. The Northeast monsoon rain occurs
between October to December and contribute to the rainfall by about 60% of the
total rainfall. Monthly variations in the rainfall for past available 10 years are given
in Table - 3.3.
Cloud Cover
Generally light clouds are observed during winter mornings. During pre-monsoon
and the post-monsoon evenings the skies are either clear or lightly clouded. But in
post-monsoon mornings as well as monsoon mornings heavy clouds are commonly
observed. Whereas in the evening time the skies are light to moderately clouded
throughout the year.
Special Weather Phenomena
Thunderstorms are frequent in pre-monsoon, post monsoon and early North-east
monsoon seasons. Occasional squalls occur in association with thunderstorms in the
later pre-monsoon season.
On an average three to four severe cyclonic storms form in the Bay of Bengal,
(mostly from April to June in pre-monsoon and September to December in post-
monsoon season). It is observed that cyclonic storms are five times more frequent
in the Bay of Bengal than in Arabian Sea. This is quite evident from the hazards that
the eastern coast faces year after year compared to west coast. The seasonal
frequencies of cyclones in East Coast of India during 1891-1982 are given in Table-
3.4.
Wind Speed/Direction
The wind rose for the study period representing pre-monsoon, monsoon, post-
monsoon and winter season along with annual wind rose are shown in Figure-
3.5 (A), (B) & (C) and presented in Table-3.5.
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TABLE-3.3
CLIMATOLOGICAL DATA - IMD, CHENNAI
Month Temperature (0C)
Relative Humidity (%)
Atmospheric Pressure (Mb)
Rainfall (mm)
Max Min Avg. 0830 1730 0830 1730
January 33.3 17.0 26.1 100 38 1016.5 1013.6 23.8
February 34.9 16.0 25.2 95 31 1012.2 1009.0 6.8
March 38.7 18.2 27.5 91 28 1010.6 1007.1 15.1
April 42.7 21.0 32.0 96 39 1008.4 1004.3 24.7
May 43.4 21.6 32.2 100 15 1004.5 1000.8 51.7
June 42.8 21.2 32.5 100 32 1003.5 999.9 52.6
July 39.5 22.3 31.0 95 35 1004.2 1000.7 83.5
August 39.0 22.0 31.0 98 32 1004.9 1001.1 124.3
September 37.8 21.5 29.5 97 35 1006.3 1002.4 118.0
October 35.9 22.4 28.7 98 46 1008.5 1005.3 267.0
November 34.4 18.0 27.0 99 42 1010.9 1003.1 308.0
December 31.7 17.8 25.0 100 34 1012.9 1010.0 139.1
TABLE-3.4
SEASONAL FREQUENCIES OF CYCLONES IN EAST COAST OF INDIA
Month Seasonal Frequency
January 4
February 0
March 2
April 11
May 15
June 32
July 33
August 27
September 23
October 40
November 40
December 22
Total 249
TABLE-3.5
SUMMARY OF WIND PATTERN – IMD, CHENNAI
Season First predominant winds Second predominant winds Calm condition in %
0830 1730 0830 1730 0830 1730
Pre-monsoon
S (29.0) S (37.5) SSW (17.5) SSW (24.9) 10.3 1.7
Monsoon SSW (17.3) SSW (20.3) SW (16.9) S (18.1) 10.5 8.2
Post monsoon
NNE (17.0) E (15.0) N (15.5) NE (14.0) 21.0 25.0
Winter NE (16.7) S (14.6) NNE (14.0) E (11.6) 31.0 16.7
Annual SSW (12.9) S (18.9) SW (10.0) SSW (14.2) 15.8 12.9
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FIGURE-3.5 (A)
WINDROSE FOR PRE MONSOON & MONSOON SEASON-IMD, CHENNAI
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FIGURE-3.5 (B)
WINDROSE FOR POST MONSOON & WINTER SEASON-IMD, CHENNAI
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FIGURE-3.5 (C)
ANNUAL WINDROSE -IMD, CHENNAI
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Analysis of Meteorological Data Recorded at Project Site
The meteorological data recorded at the plant site during the study period (1st
May, 2014 to 31st July, 2014) is presented in Table-3.6.
TABLE-3.6
SUMMARY OF THE METEOROLOGICAL DATA AT SITE
Month Temperature (oC) Humidity (%) Total Rainfall
(mm) Max Min Max Min
May 2014 43.0 24.0 94 18 139.97
June 2014 42.0 23.0 100 21 103.64
July 2014 39.0 22.0 94 27 32.02
Temperature
It was observed that the temperature at the plant site during study period ranged
from 22.0oC to 43.0oC. The monthly variations in the temperatures are presented
in Table-3.6.
Humidity
During the period of observation, the humidity ranged from 18.0% to 100.0%.
Cloud Cover
Mostly clear skies were observed during the study period.
Wind Speed and Direction
The windrose for the study period representing pre-monsoon season is shown in
Figure-3.7. A review of the windrose diagram shows that predominant winds are
mostly from West (18.5%) followed by South (14.6%). Calm conditions were
recorded for 3.34%.
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FIGURE-3.6
SITE SPECIFIC WINDROSE (MAY – JULY 2014)
WRPLOT View - Lakes Environmental Software
WIND ROSE PLOT:
Station # 03
COMMENTS: COMPANY NAME:
MODELER:
DATE:
8/25/2014
PROJECT NO.:
NORTH
SOUTH
WEST EAST
4%
8%
12%
16%
20%
WIND SPEED (m/s)
>= 11.1
8.8 - 11.1
5.7 - 8.8
3.6 - 5.7
2.1 - 3.6
0.5 - 2.1
Calms: 3.34%
TOTAL COUNT:
719 hrs.
CALM WINDS:
3.34%
DATA PERIOD:
Start Date: 1/1/2014 - 00:00End Date: 1/30/2014 - 23:00
AVG. WIND SPEED:
3.57 m/s
DISPLAY:
Wind SpeedDirection (blowing from)
WIND ROSE PLOT: Station name: Existing plant site of ARS Metals Pvt. Ltd.
DISPLAY:
Wind speed
Direction (Blowing from)
COMPANY NAME: ARS METALS PVT. LTD.
DATA PERIOD: START DATE: 1/05/2014 – 00:00
END DATE: 31/07/2014 – 23:00
MODELER:
VIMTA LABS LIMITED
PREDOMINANT WIND
DIRECTION: WEST (258.75o – 281.25 o)
DATE:
2014 AUGUST 25 PROJECT NO.: 002/AMBA/ARS AVG. WIND SPEED:
3.57 m/s
CALM WINDS: 3.34 %
COMMENTS:
18.49%
14.56%
11.94%
10.77%
9.61%
6.99%
10.63%
7.86%
3.78%
2.91% 1.31%
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3.6 Air Quality
The ambient air quality with respect to the study zone of 10-km radius around the
project site forms the baseline information. The various sources of air pollution in
the region are industries and vehicular traffic. The prime objective of the baseline
air quality study was to assess the existing air quality of the area. The study area
represents mostly rural environment.
This section describes the selection of sampling locations, methodology adopted for
sampling, analytical techniques and frequency of sampling.
3.6.1 Methodology adopted for Air Quality Survey
Selection of Sampling Locations
The baseline status of the ambient air quality has been assessed through a
scientifically designed ambient air quality-monitoring network. The design of
monitoring network in the air quality surveillance program has been based on the
following considerations:
Meteorological conditions on synoptic scale;
Topography of the study area;
Representatives of regional background air quality for obtaining baseline status;
Representatives of likely impact areas.
Ambient Air Quality Monitoring (AAQM) stations were set up at eight locations with
due consideration to the above mentioned points. Table-3.7 gives the details of
environmental setting around each monitoring station. The location of the selected
stations with reference to the project site is given in the same table and shown in
Figure-3.7.
TABLE-3.7
DETAILS OF AMBIENT AIR QUALITY MONITORING LOCATIONS
Station Code
Name of the Station Distance &
direction w.r.t
project site (km)
AAQ 1 Plant site --- AAQ 2 Gangadoddi 5.8 km, East AAQ 3 Valaimadu 4.1 km, NE AAQ 4 Edur 5.1 km, North AAQ 5 Surapundi 3.6 km, NW AAQ 6 Muttureddikandigai 4.4 km, SE AAQ 7 Amirtamangalam 2.7 km, SW AAQ 8 Vaniyamalli 3.5 km, WSW
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FIGURE-3.7
AIR QUALITY SAMPLING LOCATIONS
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Frequency and Parameters for Sampling
The following frequency has been adopted for sampling:
Ambient air quality monitoring has been carried out with a frequency of two days
per week at all locations for study period from 1st May 2014 to 31st July 2014. The
baseline data of air environment is generated for the following parameters:
Particulate Matter (PM10);
Particulate Matter (PM2.5);
Sulphur dioxide (SO2);
Nitrogen dioxide (NO2);
Carbon monoxide (CO);
Ozone (O3);
Ammonia (NH3);
Lead (Pb);
Arsenic (As);
Nickel (Ni);
Benzene (C6H6); and
Benzo(a)Pyrene
Duration of Sampling
The sampling duration for PM10, PM2.5, SO2, NO2, Pb, NH3, C6H6, BaP, As and Ni was
twenty-four hourly continuous samples per day and CO & O3 was sampled for 8–hrs
continuous thrice a day. This is to allow a comparison with the present revised
standards mentioned in the latest Gazette notification of the Central Pollution
Control Board (CPCB) (November 16, 2009).
TABLE-3.8
MONITORED PARAMETERS AND FREQUENCY OF SAMPLING
Parameters Sampling Frequency
PM10 24 hourly sample twice a week for three months
PM2.5 24 hourly sample twice a week for three months
Sulphur dioxide (SO2) 24 hourly sample twice a week for three months
Oxides of Nitrogen (NOX) 24 hourly sample twice a week for three months
Ozone (O3) 08 hourly sample twice a week for three months
Ammonia (NH3) 24 hourly sample twice a week for three months
Lead (Pb) 24 hourly sample twice a week for three months
Arsenic (As) 24 hourly sample twice a week for three months
Nickel (Ni) 24 hourly sample twice a week for three months
Carbon Monoxide (CO) 08 hourly sample twice a week for three months
Benzene (C6H6) 24 hourly sample twice a week for three months
Benzo(a)Pyrene 24 hourly sample twice a week for three months
Mercury (Hg) 24 hourly samples twice a week for three months
Method of Analysis
The air samples were analyzed as per standard methods specified by Central
Pollution Control Board (CPCB), IS: 5184 and American Public Health Association
(APHA).
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3.6.2 Instruments used for Sampling
Respirable Dust Samplers (APM-460 model) have been used for monitoring
Suspended Particulate Matter (SPM), Respirable Particulate Matter (PM10) and
gaseous pollutants like SO2 and NO2. Fine Dust Samplers of Polltech instruments
were used for monitoring PM2.5. Glass tubes were deployed for collection of grab
samples of carbon monoxide. Gas Chromatography techniques have been used for
the estimation of CO.
3.6.3 Instruments used for Analysis
The make and model of the instruments used for analysis of the samples collected
during the field monitoring are given in Table-3.9.
TABLE-3.9
INSTRUMENTS USED FOR ANALYSIS OF SAMPLES
Sr. No. Instrument Name Parameters
1 Spectrophotometer SO2, NOx, O3
2 Electronic Balance TSPM, PM10, PM2.5
3 Gas Chromatograph with FID, pFPD, ECD CO
3.6.4 Sampling and Analytical Techniques
The techniques used for ambient air quality monitoring and minimum detectable
levels are given in Table-3.10.
TABLE-3.10
TECHNIQUES USED FOR AMBIENT AIR QUALITY MONITORING
Sr. No.
Parameters Test method Minimum
detectable limit
1 PM10 Gravimetric (Respirable dust sampling / High volume sampling)
5.0 g/m3
2 PM2.5 Gravimetric (FRM method / Low volume sampling)
2.0 g/m3
3 Sulphur dioxide (SO2) Modified West & Gaeke method 4.0 g/m3
4 Nitrogen dioxide (NO2) Sodium Arsenite method 9.0 g/m3
5 Ozone (O3) Spectrophotometric method 2.0 g/m3
6 Ammonia (NH3) Indo-phenol blue method 20.0 g/m3
7 Lead (Pb) AAS/ICP-MS method after sampling on EPM filter paper
0.05 ng/m3
8 Arsenic (As) AAS/ICP-MS method after sampling on EPM filter paper
0.2 ng/m3
9 Nickel (Ni) AAS/ICP-MS method after sampling on EPM filter paper
0.10 ng/m3
10 Carbon Monoxide (CO) Adsorption and extraction followed by GC-MS analysis
12.5 g/m3
11 Benzene (C6H6) Adsorption and desorption followed by GC-MS analysis
1.0 ng/m3
12 Benzo (a) Pyrene (BaP) Solvent extraction followed by GC-MS 1.0 ng/m3
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3.6.5 Presentation of Primary Data
Various statistical parameters like 98th percentile, average, maximum and minimum values have been computed from the observed
raw data for all the AAQ monitoring stations. The summary of these results is presented in Table-3.11
TABLE-3.11
SUMMARY OF AMBIENT AIR QUALITY RESULTS
Parameters AAQ-1 AAQ-2 AAQ-3 AAQ-4 AAQ-5 AAQ-6 AAQ-7 AAQ-8
PM10
( g/m3)
Maximum 83.1 51.9 44.4 38.7 41.6 51.6 60.6 38.1
Minimum 72.7 45.4 40.0 33.9 36.4 45.2 53.0 33.4
Average 78.3 48.9 41.9 36.5 39.2 48.6 57.1 35.9
98%tile 82.7 51.7 44.2 38.6 41.4 51.4 60.3 38.0
PM2.5
(µg/m3)
Maximum 27.4 17.1 14.7 12.8 13.7 17.0 20.0 12.6
Minimum 24.0 15.0 13.2 11.2 12.0 14.9 17.5 11.0
Average 25.8 16.1 13.8 12.0 12.9 16.0 18.8 11.8
98%tile 27.3 17.0 14.6 12.7 13.7 17.0 19.9 12.5
SO2
( g/m3)
Maximum 26.9 14.6 13.2 8.2 10.7 14.8 15.7 11.1
Minimum 19.5 11.0 10.0 6.4 7.9 10.7 11.3 7.9
Average 22.5 12.2 11.4 7.4 9.0 12.7 13.5 9.5
98%tile 26.9 14.6 13.1 8.2 10.7 14.8 15.7 11.1
NO2
( g/m3)
Maximum 33.2 23.1 19.1 12.2 14.3 25.6 27.1 19.1
Minimum 26.1 17.9 14.5 9.6 9.3 15.9 16.9 11.9
Average 30.6 19.8 16.1 11.0 12.7 19.5 20.6 14.5
98%tile 33.2 22.8 19.0 12.1 14.3 25.4 26.9 18.9
CO ( g/m3)
Maximum 343 236 213 175 217 175 284 199
Minimum 259 178 173 141 179 150 243 170
Average 282 194 183 153 191 157 256 179
98%tile 338 232 207 175 217 173 282 197
Note: Ozone (O3), Ammonia (NH3), Lead (Pb), Arsenic (As), Nickel (Ni), Benzene (C6H6) and Benzo(a)Pyrene (BaP) are found to exist
below Detectable Limit.
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3.6.6 Observations of Primary Data
The three months ambient air quality data are given as Annexure – 9.
PM10: The maximum and minimum concentrations for PM10 were recorded as
83.1 g/m3 and 33.4 g/m3 respectively. The maximum concentration was
recorded at Plant Site (AAQ1) and the minimum concentration was recorded at
Vaniyamalli (AAQ8). The average values were observed to be in the range of 35.9
and 78.3 g/m3.
PM2.5: The maximum and minimum concentrations for PM2.5 were recorded as 27.4
g/m3 and 11.0 g/m3 respectively. The maximum concentration was recorded at
Plant Site (AAQ1) and the minimum concentration was recorded at Vaniyamalli
(AAQ8). The average values were observed to be in the range of 11.8 and 25.8
g/m3.
SO2: The maximum and minimum SO2 concentrations were recorded as 26.9 g/m3
and 6.4 g/m3. The maximum concentration was recorded at Plant Site (AAQ1) and
the minimum concentration was recorded at Edur (AAQ4). The average values
were observed to be in the range of 7.4 and 22.5 g/m3.
NO2: The maximum concentration of 33.2 g/m3 for NO2 was recorded at Plant Site
(AAQ1) and minimum of 9.3 g/m3 observed at Surapundi (AAQ5). The average
concentrations were ranged between 11.0 and 30.6 g/m3.
CO: The maximum concentration of 343 g/m3 was recorded at Plant site (AAQ1)
and minimum of 141 g/m3 observed at Edur (AAQ4). The average concentrations
were ranged between 153 and 282 g/m3.
The concentrations of PM10, PM2.5, SO2, NOX and CO are observed to be well within
the standards prescribed by Central Pollution Control Board (CPCB) for Industrial,
Rural, Residential and other area. Other parameters including Ozone (O3),
Ammonia (NH3), Lead (Pb), Arsenic (As), Nickel (Ni), Benzene (C6H6),
Benzo(a)Pyrene (BaP) & Mercury (Hg) are found to exist below detectable limits.
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3.7 Noise Level Survey
The physical description of sound concerns its loudness as a function of frequency.
Noise in general is sound which is composed of many frequency components of
various loudness distributed over the audible frequency range. Various noise scales
have been introduced to describe, in a single number, the response of an average
human to a complex sound made up of various frequencies at different loudness
levels. The most common and universally accepted scale is the A weighted Scale
which is measured as dB (A). This is more suitable for audible range of 20 Hz to
20,000 Hz. The scale has been designed to weigh various components of noise
according to the response of a human ear.
The impact of noise sources on surrounding community depends on:
Characteristics of noise sources (instantaneous, intermittent or continuous in
nature). It can be observed that steady noise is not as annoying as one which is
continuously varying in loudness;
The time of day at which noise occurs, for example high noise levels at night in
residential areas are not acceptable because of sleep disturbance; and
The location of the noise source, with respect to noise sensitive land use, which
determines the loudness and period of exposure.
The environmental impact of noise can have several effects varying from Noise
Induced Hearing Loss (NIHL) to annoyance depending on loudness of noise. The
environmental impact assessment of noise due to construction activity, and
vehicular traffic can be undertaken by taking into consideration various factors like
potential damage to hearing, physiological responses, annoyance and general
community responses. Noise monitoring has been undertaken for 24-hr duration at
each location.
3.7.1 Identification of Sampling Locations
A preliminary reconnaissance survey has been undertaken to identify the major
noise generating sources in the area. Noise at different noise generating sources
has been identified based on the activities in the village area, ambient noise due to
industries and traffic and the noise at sensitive areas like hospitals and schools.
The noise monitoring has been conducted for determination of noise levels at ten
locations in the study area. The environmental settings of each noise monitoring
location is given in Table-3.12 and depicted in Figure-3.8.
3.7.2 Method of Monitoring
Sound Pressure Level (SPL) measurements were measured at all locations; one
reading for every hour was taken for 24 hours. The day noise levels have been
monitored during 6 am to 10 pm and night levels during 10 pm to 6 am at all the
monitoring locations within the study area.
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3.7.3 Instrument Used for Monitoring
Noise levels were measured using integrated sound level meter manufactured by
Quest Technologies, USA (Model No.2900). The integrating sound level meter is
an integrating/ logging type with Octave filter attachment (model OB-100) with
frequency range of 31.5 to 16000 Hz. This instrument is capable of measuring the
Sound Pressure Level (SPL), Leq and octave band frequency analysis.
TABLE – 3.12
DETAILS OF NOISE MONITORING LOCATIONS
Location Code
Location (Village)
Distance & direction w.r.t
plant site (km)
Zone
N1 Plant site --- Industrial
N2 Melpakkam 2.5 km, North Residential
N3 Gopalreddikandigai 2.1 km, NE Residential
N4 Bodireddikandigai 3.5 km, East Residential
N5 Billakuppam 2.3 km, SE Residential
N6 Amirthamangalam 2.5 km, SSW Industrial
N7 Vaniyamalli 3.4 km, West Residential
N8 Ramachandrapuram 3.1 km, NW Residential
N9 Palayapalayam 1.8 km, East Residential
N10 Gumpuahintala 3.1 km, North Residential
3.7.4 Parameters Measured During Monitoring
For noise levels measured over a given period of time interval, it is possible to
describe important features of noise using statistical quantities. This is calculated
using the percent of the time certain noise levels are exceeding the time interval.
The notation for the statistical quantities of noise levels are described below:
L10 is the noise level exceeded 10 per cent of the time;
L50 is the noise level exceeded 50 per cent of the time ; and
L90 is the noise level exceeded 90 per cent of the time.
Equivalent Sound Pressure Level (Leq):
The Leq is the equivalent continuous sound level which is equivalent to the same
sound energy as the actual fluctuating sound measured in the same period. This is
necessary because sound from noise source often fluctuates widely during a given
period of time.
This is calculated from the following equation:
(L10 - L90)2
Leq = L50 + ------------
60
Lday is defined as the equivalent noise level measured over a period of time during
day (6 am to 10 pm).
Lnight is defined as the equivalent noise level measured over a period of time during
night (10 pm to 6 am). A noise rating developed by Environmental protection
Agency (EPA) for specification of community noise from all the sources is the Day-
Night Sound Level, (Ldn).
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FIGURE-3.8
NOISE QUALITY MONITORING LOCATIONS
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Day-Night Sound Level (Ldn):
The noise rating developed for community noise from all sources is the Day-Night
Sound Level (Ldn). It is similar to a 24 hr equivalent sound level except that during
night time period (10 pm to 6 am) a 10 dB (A) weighting penalty is added to the
instantaneous sound level before computing the 24 hr average.
This night time penalty is added to account for the fact that noise during night
when people usually sleep is judged as more annoying than the same noise during
the day time.
The Ldn for a given location in a community may be calculated from the hourly Leq's,
by the following equation.
Ldn = 10 log {1/24[16(10 Ld/10) + 8 (10(Ln+10)/10)]}
Where Ld is the equivalent sound level during the daytime (6 am to 10 pm) and Ln
is the equivalent sound level during the nighttime (10 pm to 6 am).
3.7.5 Presentation of Results
The statistical analysis is done for measured noise levels at ten locations for once
during study period. The parameters are analyzed for Lday, Lnight, and Ldn. These
results are tabulated in Table-3.13.
TABLE-3.13
NOISE LEVELS IN THE STUDY AREA
Code Location L10 L50 L90 LEQ Lday Lnight Ldn
N1 Plant site 55.8 51.7 44.1 54.0 56.9 42.8 56.0
N2 Melpakkam 69.2 63.8 61.9 64.7 68.2 53.9 67.0
N3 Gopalreddikandigai 69.1 64.1 61.8 65.0 66.9 51.8 65.9
N4 Bodireddikandigai 54.9 48.2 42.9 50.6 53.3 41.7 52.7
N5 Billakuppam 59.5 50.3 42.4 55.1 55.8 43.4 55.2
N6 Amirthamangalam 49.4 45.1 42.0 46.7 47.6 43.8 51.0
N7 Vaniyamalli 50.6 46.1 42.7 47.1 49.1 44.2 51.7
N8 Ramachandrapuram 49.8 45.9 42.2 46.9 47.7 44.1 51.2
N9 Palayapalayam 48.4 44.6 40.8 45.6 46.8 42.9 50.1
N10 Gumpuahintala 47.3 43.1 39.2 44.2 45.2 40.8 48.2
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3.8 Soil characteristics
It is essential to determine the potentiality of soil in the area and to identify the
impacts of urbanization on soil quality. Accordingly, the soil quality assessment
has been carried out.
3.8.1 Data Generation
The sampling locations have been identified with the following objectives:
To determine the baseline soil characteristics of the study area;
To determine the impact of proposed expansion activity on soil
characteristics; and
To determine the impact on soils more importantly from agricultural
productivity point of view.
Eight locations within 10-km radius of the plant boundary were selected for soil
sampling. At all location, soil samples were collected from three different depths
viz. 30 cm, 60 cm and 90 cm below the surface and are homogenized. This is in
line with IS: 2720 and Methods of Soil Analysis, Part-1, 2nd edition, 1986 of
(American Society for Agronomy and Soil Science Society of America). The
homogenized samples were analyzed for physical and chemical characteristics.
The soil samples were collected during pre-monsoon season. The samples have
been analyzed as per the established scientific methods for physico-chemical
parameters. The heavy metals have been analyzed by using Atomic Absorption
Spectrophotometer and Inductive Coupled Plasma Analyzer. The methodology
adopted for each parameter is described in Table-3.14.
TABLE-3.14
ANALYTICAL TECHNIQUES FOR SOIL ANALYSIS
Parameter Method (ASTM Number)
Grain size distribution Sieve analysis (D 422 – 63)
Textural classification Chart developed by Public Roads
Administration
Bulk density Sand replacement, core cutter
Sodium absorption ratio Flame colorimetric (D 1428-82)
pH pH meter (D 1293-84)
Electrical conductivity Conductivity meter (D 1125-82)
Nitrogen Kjeldahl distillation (D 3590-84)
Phosphorus Molybdenum blue, colorimetric (D 515-82)
Potassium Flame photometric (D 1428-82)
Copper AAS (D 1688-84)
Iron AAS (D 1068-84)
Zinc AAS (D 1691-84)
Boron Surcumin, colorimetric (D 3082-79)
Chlorides Argentometric (D 512-81 Rev 85)
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The details of the soil sampling locations are given in Table-3.15 and shown in
Figure-3.9.
TABLE-3.15
DETAILS OF SOIL SAMPLING LOCATIONS
Code No.
Location
Distance &
direction w.r.t. plant site (Km)
S 1 Plant site --- S 2 Melpakkam 2.1 km, NNW S 3 Gopalreddikandigai 1.9 km, NE S 4 Bodireddikandigai 2.9 km, East S 5 Billakuppam 1.8 km, SE S 6 Amirthamangalam 2.5 km, SSW S 7 Vaniyamalli 3.1 km, West S 8 Ramachandrapuram 2.8 km, NW
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FIGURE-3.9
SOIL SAMPLING LOCATIONS
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3.8.2 Baseline Soil Status
The soil characteristics are shown in Table-3.16. The results are compared with standard soil classification given in Table-3.17.
TABLE-3.16
SOIL ANALYSIS RESULTS
Sr. No. Parameter UOM S1 S2 S3 S4 S5 S6 S7 S8
1 pH (1:5 Aq.Extract) ---- 7.8 7.6 7.9 7.4 7.5 7.6 7.8 7.4
2 Conductivity (1:5 Aq.Extract) S/cm 164 182 150 143 201 182 210 167
3 Texture ---- Sandy clay Sandy clay Sandy clay Sandy clay Sandy clay Sandy clay Sandy clay Sandy clay
4 Sand % 49 46 51 49 52 49 36 49
5 Silt % 15 16 15 12 11 18 13 15
6 Clay % 36 38 34 39 37 33 51 36
7 Bulk Density mg/cc 1.1 1.0 1.2 1.0 1.2 1.1 1.0 1.1
8 Exchangeable Calcium as Ca mg/kg 1200 1600 4998 4399 1999 1799 3799 1599
9 Exchangeable Magnesium as Mg g/kg 729 486 607 972 850 607 243 486
10 Exchangeable Sodium as Na mg/kg 151 307 250.4 243.5 194.4 181.9 211.4 152.9
11 Available Potassium as K Kg/ha 276.2 303.8 383.0 244.9 482.4 280.4 306.8 424.2
12 Available Phosphorous as P Kg/ha 75.9 89.4 64.9 61.6 80.5 82.2 76.5 94.4
13 Available Nitrogen as N Kg/ha 81.9 121.9 91.8 103.0 83.4 71.4 95.8 87.2
14 Organic Matter % 0.77 1.26 0.79 1.06 0.72 0.67 0.99 0.82
15 Organic Carbon % 0.45 0.73 0.46 0.62 0.42 0.39 0.57 0.47
16 Water Soluble Chloride as Cl mg/kg 88.6 283.6 248.1 319.0 141.8 106.3 78.0 141.8
17 Water Soluble Sulphate as SO4 mg/kg 51.6 153.2 138.7 93.5 114.5 96.7 101.6 117.7
18 Sodium Absorption Ratio ---- 0.38 0.77 0.40 0.39 0.41 0.42 0.40 0.38
19 Aluminium % 1.32 1.42 1.65 1.44 1.12 1.63 1.54 1.72
20 Total Iron % 1.12 1.48 1.72 1.53 1.34 1.08 1.16 1.13
21 Manganese mg/kg 153 120 138 158 164 210 184 154
22 Boron mg/kg 25.4 25.7 32.1 29.4 28.3 24.6 27.2 30.4
23 Zinc mg/kg 48 54 70 86.7 62 82.4 61.3 68.7
It has been observed that the texture of soil is sandy clay in the study area. It has been observed that the pH of the soil ranged from
7.4 to 7.9. The electrical conductivity was observed to be in the range of 143 – 210.0 µmhos/cm.
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TABLE-3.17
STANDARD SOIL CLASSIFICATION
Sr. No. Soil Test Classification
1 pH <4.5 Extremely acidic
4.51 - 5.50 Very strongly acidic
5.51 - 6.0 moderately acidic
6.01 - 6.50 slightly acidic
6.51 - 7.30 Neutral
7.31 - 7.80 slightly alkaline
7.81 - 8.50 moderately alkaline
8.51 - 9.0 strongly alkaline
9.01 very strongly alkaline
2 Salinity Electrical
Conductivity (mmhos/cm)
(1 ppm = 640 mmho/cm)
Upto 1.00 Average
1.01 - 2.00 harmful to germination
2.01 - 3.00 harmful to crops
(sensitive to salts)
3 Organic Carbon Upto 0.2: very less
0.21 – 0.4: less
0.41 – 0.5 medium,
0.51 – 0.8: on an average
sufficient
0.81 – 1.00: sufficient
>1.0 more than sufficient
4 Nitrogen (Kg/ha) Upto 50 very less
51 – 100 less
101 – 150 good
151 – 300 Better
>300 sufficient
5 Phosphorus (Kg/ha) Upto 15 very less
16 – 30 less
31 – 50 medium,
51 – 65 on an average sufficient
66 – 80 sufficient
>80 more than sufficient
6 Potash (Kg/ha) 0 – 120 very less
120 – 180 less
181 – 240 medium
241 – 300 average
301 – 360 better
>360 more than sufficient Source: Handbook of Agriculture, ICAR, New Delhi
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3.9 Water Quality
Selected water quality parameters of ground water and surface water resources
within the study area has been studied for assessing the water environment and
evaluate anticipated impact of the proposed expansion project. Understanding the
water quality is essential in preparation of Environmental Impact Assessment and
to identify critical issues with a view to suggest appropriate mitigation measures for
implementation.
The purpose of this study is to:
Assess the water quality characteristics for critical parameters;
Evaluate the impacts on agricultural productivity, habitat conditions,
recreational resources and aesthetics in the vicinity; and
Prediction of impact on water quality by this project and related activities.
The information required has been collected through primary surveys and
secondary sources.
3.9.1 Methodology
Reconnaissance survey was undertaken and monitoring locations were finalized
based on:
Drainage pattern;
Location of residential areas representing different activities/likely impact
areas; and
Likely areas, which can represent baseline conditions.
Water sources covering 10-km radial distance were examined for physico-chemical,
heavy metals and bacteriological parameters in order to assess the effect of
industrial and other activities on water. The samples were collected and analyzed
as per the procedures specified in 'Standard Methods for the Examination of Water
and wastewater' published by American Public Health Association (APHA).
Samples for chemical analysis were collected in polyethylene carboys. Samples
collected for metal content were acidified with 1 ml HNO3. Samples for
bacteriological analysis were collected in sterilized glass bottles. Selected physico-
chemical and bacteriological parameters have been analyzed for projecting the
existing water quality status in the study area. Parameters like temperature,
Dissolved Oxygen (DO), free Chlorine and pH were analyzed at the time of sample
collection.
3.9.2 Water Sampling Locations
Water samples were collected from 6 ground water and 2 surface water-sampling
locations. These samples were taken as grab samples and were analyzed for
various parameters to be compared with the standards for drinking water as per
IS:10500 (2012). The water sampling locations are listed below in Table-3.18 and
are depicted in Figure-3.10.
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TABLE-3.18
DETAILS OF WATER SAMPLING LOCATIONS
Code Location Distance w.r.t.
Project Site (km)
Ground water
GW1 Plant site --- GW2 Pappankuppam 3.0 km, East GW3 Billakuppam 2.3 km, SE GW4 Amirthamangalam 2.5 km, SSW GW5 Iguvarpalayam 2.0 km, NW GW6 Gopalreddikandigai 2.2 km, NE
Surface water
SW1 Chithoornatham pond 1.0 km, West SW2 Arani river 7.7 km, SW
3.9.3 Presentation of Results
Ground Water Quality
The results of the parameters analyzed for the 6 Ground water samples are
presented in Table-3.19 and are compared with the standards for drinking water
as per IS: 10500 (2012).
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FIGURE-3.10
WATER SAMPLING LOCATIONS
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TABLE 3.19
GROUND WATER QUALITY
Sr. No.
Parameter Units IS:10500
Limits GW1 GW2 GW3 GW4 GW5 GW6
1 pH - 6.5 to 8.5 7.7 7.6 7.8 7.6 7.4 7.5
2 Colour Hazen 5 (15) <1.0 1.0 1.0 <1.0 1.0 2.0
3 Odour - UO Un-objectionable
4 Conductivity us/cm $ 447 693 635 450 505 773
5 Taste - Ag Agreeable
6 Turbidity NTU 1 (5) 2 3 3 2 2 3.0
7 Total hardness as CaCO3
mg/l 200 (600) 220 350 300 230 240 190
8 Total Dissolved solids mg/l 500 (2000) 223 355 316 234 264 414
9 Chlorides as Cl mg/l 250 (1000) 24.8 35.5 53.2 28.4 28.4 53.2
10 Residual free Chlorine
mg/l 0.2 Min <0.2 <0.2 <0.2 <0.2 <0.2 <0.2
11 Fluoride as F mg/l 1.0 (1.5) 0.9 0.8 0.6 0.7 0.9 1.1
12 Calcium as Ca mg/l 75 (200) 48 76 60 52 72 52
13 Magnesium as Mg mg/l 30 (100) 24.3 38.8 36.4 24.3 14.6 14.6
14 Sulphates as SO4 mg/l 200 (400) 8.6 2.6 2.1 2.4 2.1 2.1
15 Nitrates as NO3 mg/l 45 3.9 11.2 37.3 11.6 17.4 36
16 Phenolics as C6H5OH mg/l 0.001 <0.001 <0.001 <0.001 <0.001 <0.001 <0.001
17 Cyanide as CN mg/l 0.05 <0.02 <0.02 <0.02 <0.02 <0.02 <0.02
18 Alkalinity as CaCO3 mg/l 200 (600) 175 300 200 180 200 280
19 Boron mg/l 1 0.02 0.03 0.02 0.03 0.04 0.02
20 Sodium as Na mg/l $ 4.9 6.2 5.6 3.9 5.5 78.9
21 Potassium as K mg/l $ 2.9 3.5 1.3 3 2.9 8.5
22 Iron as Fe mg/l 0.3 <0.01 <0.01 0.07 0.04 0.06 0.04
23 Copper as Cu mg/l 0.05 <0.01 <0.01 <0.01 <0.01 <0.01 0.01
24 Manganese as Mn mg/l 0.1 0.01 0.01 0.01 0.01 0.01 0.01
25 Aluminium as Al mg/l 0.03 0.1 0.07 0.12 0.21 0.11 0.34
26 Chromium as Cr+6 mg/l 0.05 <0.05 <0.05 <0.05 <0.05 <0.05 <0.05
27 Cadmium as Cd mg/l 0.01 <0.01 <0.01 <0.01 <0.01 <0.01 0.01
28 Selenium as Se mg/l 0.01 <0.01 <0.01 <0.01 <0.01 <0.01 <0.01
29 Arsenic as As mg/l 0.01 <0.01 <0.01 <0.01 <0.01 <0.01 <0.01
30 Lead as Pb mg/l 0.05 <0.01 <0.01 <0.01 <0.01 <0.01 <0.01
31 Zinc as Zn mg/l 5 (15) 0.01 <0.01 0.02 0.01 0.03 0.01
32 Mercury as Hg mg/l 0.001 <0.001 <0.001 <0.001 <0.001 <0.001 <0.001
33 Anionic detergents as MBAS
mg/l 0.2 <0.2 <0.2 <0.2 <0.2 <0.2 <0.2
34 Mineral oil mg/l 0.01 <0.01 <0.01 <0.01 <0.01 <0.01 <0.01
35 Pesticides mg/l Absent Absent Absent Absent Absent Absent Absent
36 E. coli - Absent Absent Absent Absent Absent Absent absent
37 Total Coliforms MPN/
100
10 <2 <2 <2 <2 <2 <2
U.O.: Un-objectionable $: Not specified NR – No Relaxation
The analysis results indicate that the pH ranges in between 7.4 to 7.8, which is well
within the specified standard of 6.5 to 8.5. The Total Dissolved Solids (TDS)
concentration is found to be ranging in between 223 to 414 mg/l.
Total hardness was observed to be ranging from 190 to 350 mg/l. The Chlorides
and Nitrates are found ranging from 24.8-53.2 mg/l and 3.9 – 37.3 mg/l.
Potassium found ranging in between 1.3 to 8.5 mg/l. The Heavy metals are found
to be below detectable limits.
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Surface Water Quality
The results of the parameters analyzed for the surface water samples are
presented in Table-3.20.
TABLE 3.20
SURFACE WATER QUALITY
Sr. No. Parameter Unit IS:10500
Limits SW1 SW2
1. pH - 6.5-8.5 (NR) 8.1 7.1
2. Colour (Hazen) Hazen 5(15) <1 <1
3 Taste - Agreeable Ag Ag
4 Odour - UO U.O U.O
5 Conductivity ( s/cm) µS/cm $ 961 1086
6 Turbidity (NTU) NTU 1(5) 2 3
7 Total Dissolved Solids mg/l 500 (2000) 652 745
8 Total Hardness as CaCO3 mg/l 200 (600) 570 310
9 Total Alkalinity mg/l 200 (600) 280 231
10 Calcium as Ca2+ mg/l 75 (200) 42.0 25.3
11 Magnesium as Mg2+ mg/l 30 (100) 11.0 11.6
12 Residual Chlorine mg/l 0.2 Min <0.2 <0.2
13 Boron mg/l 1 0.08 0.03
14 Chloride as Cl- mg/l 250 (1000) 211 105.5
15 Sulphate as SO4 2+ mg/l 200 (400) 28.7 38.1
16 Fluorides as F mg/l 1.0 (1.5) 0.5 0.6
17 Nitrate as NO3 mg/l 45 (NR) 15.0 15.4
18 Sodium as Na+ mg/l $ 89.2 66.3
19 Potassium as K+ mg/l $ 20.1 3.2
20 Phenolic Compounds mg/l 0.001 (0.002) <0.001 <0.001
21 Cyanides mg/l 0.05 (NR) <0.02 <0.02
22 Anionic Detergents mg/l 0.2 (0.1) <0.1 <0.1
23 Mineral Oil mg/l 0.01 (0.03) <0.01 <0.01
24 Cadmium as Cd mg/l 0.01 (NR) <0.01 <0.01
25 Arsenic as As mg/l 0.01 (NR) <0.01 <0.01
26 Copper as Cu mg/l 0.05 (1.5) 0.05 0.13
27 Lead as Pb mg/l 0.05 (NR) <0.01 <0.01
28 Manganse as Mn mg/l 0.1 (0.3) 0.02 0.01
29 Iron as Fe mg/l 0.3 (1.0) 0.24 0.16
30 Chromium as Cr+6 mg/l 0.05 (NR) <0.05 <0.05
31 Selenium as Se mg/l 0.01 (NR) <0.01 <0.01
32 Zinc as Zn mg/l 5 (15) 0.17 0.24
33 Aluminium as Al mg/l 0.03 (0.2) <0.01 <0.01
34 Mercury as Hg mg/l 0.001 (NR) <0.001 <0.001
35 Pesticides mg/l Absent Absent Absent
36 E. Coli - Absent Absent Absent
37 Total Coliforms MPN/100 ml
10 Absent Absent
U.O. : Un-objectionable $ : Not specified NR – No Relaxation
The analysis results indicate that the pH value at SW1 & SW2 was found to exist as
8.1 & 7.1 respectively. The Total Dissolved Solids (TDS) concentration was found
as 652 & 745.
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3.10 Ecology and Biodiversity
3.10.1 Introduction
Ecological evaluation aims at developing and applying methodologies to assess
the relevance of an area for nature conservation. As such, it is to support the
assessment of the impact of a proposed development by providing guidance on
how to describe the ecological features within the area affected, how to value
them, and how to predict the value losses caused by the development. The
evaluation of the ecological significance of an area can be undertaken from
different perspectives and consequently with different objectives. One of such
perspectives focuses on the conservation of the biological diversity or
biodiversity. Among the human activities that pose the highest threat to the
conservation of biodiversity are the developmental projects in particular. Such
projects represent artificial elements that cut through the landscape and interfere
with the natural habitat and its conditions by emissions that may be solid, liquid
and or gaseous. This in turn influences the abundance and distribution of plant
and animal species, i.e., the biodiversity of the areas impacted.
Most of the background data needs to be acquired from the governmental
agencies or the scientific literature. This information is typically complemented by
field visit, site surveys and sample collection. The description of the actual
ecological assessment provided by the ecological baseline study serves to set a
reference for the subsequent impact analysis. Moreover, it helps decision-makers
and EIA reviewers to become familiar with the environmental features and the
needs of the study area
3.10.2 Objectives of the Study
The present study was undertaken with the following objectives to assess both
terrestrial and aquatic habitats of the study area:
To assess the nature and distribution of vegetation in and around the existing
project site.
To assess the fauna in the study area;
To understand the ecology of the water bodies;
To ascertain the migratory routes of fauna, presence of breeding grounds
and sensitive habitats in the study area, if any;
To assess the presence of protected areas in the study area;
To review the information from secondary sources and discuss the issues
of concern with the relevant authority and stakeholders;
Impact prediction based on primary and secondary data sources to
formulate mitigation measures.
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3.10.3 Methodology
To achieve the above objectives a detailed study of the area was undertaken with
the existing site as its centre. The different methods adopted were as follows:
Generation of primary data by undertaking systematic ecological studies in
the study area;
Primary data collection for flora through random sampling method for
trees, shrubs and herbs from the selected locations to know the vegetation
cover qualitatively.
To spot the fauna in the study area and also to identify the fauna by
secondary indicators such as pugmarks, scats, fecal pallets, calls and other
signs.
For ecological information, the secondary sources such as local officials,
villagers and other stakeholders were interviewed.
Sourcing secondary data with respect to the study area from published
literature.
The list of Terrestrial and Aquatic sampling locations in the study area is
presented in Table-3.21 and shown in Figure-3.11.
TABLE-3.21
LIST OF ECOLOGICAL SAMPLING LOCATIONS
Code Name of the Locations
Distance from
Plant Site
(Km)
Direction w.r.t.
Proposed
Plant Site
Terrestrial sampling locations
TE-1 Manali R.F. Near Manali village 5.9 SSW
TE-2 Near Siruvadu village 6.7 W
TE-3 Near Nemalur village 6.6 W
TE-4 Near kondamanallur 6.2 NNW
Aquatic sampling locations
AE-1 Near Arani village 8.8 SSE
AE-2 Near Arigattura village 9.7 SE
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FIGURE-3.11
ECOLOGICAL SAMPLING LOCATIONS
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3.10.4 General Ecology of the Study Area
The area is a degraded scrub land intermixed with agriculture fields. There is one
reserved or protected forest in the study area. The region is an urbanized area
with developmental activities that include industries, stone quarries, railway lines
and roads.
Some of the area is covered with agricultural fields as well as fruit trees
cultivations. Small patches were noted of open scrublands forming pockets of
degraded vegetation. Most of the horticultural activity is dominated by coconut
and banana gardens
3.10.5 Forest Blocks
The forest area comes under broad category of Tropical semi evergreen forest of
subgroup Sothern tropical semi evergreen forests. The nearest forest block is
about 5.6 km from plant site on south west direction. The main composition of
trees in forest blocks are mainly comprised of Azadiractha indica Ficus
bengalensis, ficus religiosa, phenix spp,opuntia, Emblica officinalis, ziziphus
jujuba Eucalyptus.The list of forest blocks and their distances from plant
boundary are presented in Table-3.22.
TABLE-3.22
LIST OF FOREST BLOCKS WITHIN 10 KM RADIUS
Sr. No. Name of forest
block
Distance from the
site (km)
Direction from
the site
1 Palavakkam RF 5.6 SSW
3.10.6 Terrestrial Biodiversity
Flora of the Core area
The core are is mostly Barren land and some part of the land consists green
patces. The flora of the core area is mainly covered by the shrubs, under shrubs
and herbs.species such as Prosopis juliflora, Acacia auriculoformis, calotrophis
gigantic,Opuntia stricta, Datura metel and Trees like Khejur (phoenix dactylifera),
onla (Emblica officinalis), imli(Tamarindus indicus), Aam(Mangifera indica). The
list of flora is given in Table-3.23.
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TABLE-3.23
LIST OF FLORA IN THE CORE AREA
Sr. No. Common name Scientific name
1 Arjun Terminalia arjuna
2 Bamboo Dendrocalamus strictus
3 Kekar Garuga pinnate
4 Kusum Schleichesia oleosa
5 Babul Acacia auriculoformis
6 Mango Mangifera indica
7 Amla Emblica officinalis
8 Hairy Senna Cassia hirsute
9 Unni chedi Lantana camara
10 Carrot grass Parthenium histerophorus
3.10.7 Fauna of the Core Zone
This area hosts common mongoose, field mouse, Bandicoot rat and birds like
hose sparrow, common myna and koel white throated king fisher lapwing Black
drongo There are no Schedule-I species in the core area. The list of fauna is given
in Table-3.24.
TABLE-3.24
LIST OF FAUNA IN THE CORE ZONE
Sr. No. Scientific name Common name Conservation status
as per WPA (1972)
1 Milyus migrans Common Kite Sch-IV
2 Corvus splendens House crow Sch-II
3 Acridotheres tristicus Common myna Sch-IV
4 Passer domisticus House Sparrow Sch- V
5 Eudynamis scolopaceus Koel Sch-IV
6 Calotes versicolor Common garden
lizard
Sch-IV
7 Chameleon zeylanicus Chamaeleon Sch-IV
8 Bufo melanostictus Bufo Sch-IV
9 Bandicota indica Bandicoot Sch-IV
3.10.8 Flora of the Buffer Zone
Most commonly found species in the buffer zone and along the road side were
Neem (Azadiractha indica), Ficus bengalensis, ficus religiosa, phenix spp,opuntia,
Emblica officinalis, ziziphus Eucalyptus.The list of forest blocks and their distances
from plant Acacia (Acacia nilotica) The list of flora is given in Table-3.25.
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TABLE-3.25
LIST OF FLORA FROM THE BUFFER ZONE
Sr. No. Scientific name Family
1 Emblica officinalis Euphorbiaceae
2 Mangifera indica Anacardiaceae
3 Spondias mangifera Anacardiaceae
4 Saraca asoca Caesalpiniaceae
5 Ficus religiosa Moraceae
6 Annona squamosa Annonaceae
7 Ficus bengalensis Moraceae
8 Ziziphus jojoba Rhamnaceae
9 Ficus hispida Moraceae
10 Semecarpus anacardium Anacardiaceae
11 Anacardium occidentale Anacardiaceae
12 Helictres isora Tiliaceae
13 Anogeissus latifolia Combrataceae
14 Ficus carica Moraceae
15 Ficus glomerata Moraceae
16 Ocimum sanctum Labiatae
17 Ocimum sanctum Labiatae
18 Jatropha gossypifolia Euphorbiaceae
19 Jusrtia simplex Acanthaceae
20 Jussiaea suffraticosa Onagraceae
21 Abutilon indicum Malvaceae
22 Mimosa pudica Mimosaceae
23 Osimum americanum Labiataceae
24 Desmodium trifolium Fabaceae
25 Casurina Casuarinaceae
26 Melia azadiractha Meliaceae
27 Oxalis cornicula Oxalidaceae
28 Aegle marmelos Rutaceae
29 Tephrosia purpuria Fabaceae
30 Polyalthia longifolia Annonaceae
31 Feronia elephantum Verbanaceae
3.10.9 Fauna of the Buffer Zone
Primary field studies were conducted near villages, forest areas, waste lands, along
the water bodies within 10 km radius of the project boundary and secondary data
was collected through interaction with local forest officials. The details of the same
are presented in Table-3.26.
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TABLE-3.26
LIST OF FAUNA IN THE BUFFER ZONE
Sr. No. Scientific name Common name
Conservation
status as per
WPA (1972)
I.Aves
1 Milyus migrans Common Kite Sch-IV
2 Corvus corvus Jungle crow Sch-IV
3 Corvus splendens House crow Sch-V
4 Halcyon symyrnensis White Kingfisher Sch-IV
5 Ceryle rudis Pied kingfisher Sch-IV
6 Columba livia Rock Pigeon Sch-IV
7 Bubo bubo Indian great horned Owl Sch-IV
8 Copsychus saularis Magpie Robin Sch-IV
9 Oriolus oriolus Indian Oriole Sch-IV
10 Temenuchus
pagodarum
Brahmny Myna Sch-IV
11 Acridotheres tristicus Common myna Sch-IV
12 Ploceus philippinus Weaver bird Sch-IV
13 Uroloncha striata Spotted munia Sch-IV
14 Passer domisticus House Sparrow Sch-IV
15 Megalaima merulinus Indian Cuckoo Sch-IV
16 Eudynamis scolopaceus Koel Sch-V
17 Centropus sinensis Crow Pheasant Sch-IV
18 Psittacula crammeri Rose ringed parakeet Sch-IV
19 Coracias bengalensis Indian Roller Sch-IV
20 Merops leschenaultia Chestnut headed Bee
Eater
Sch-IV
21 Alcedo atthis Common Kingfisher Sch-IV
22 Microfus affinis House swift Sch-IV
23 Caprimulgus asiaticus Common Indian jar Sch-IV
24 Bubulcus ibis Cattle Egret Sch-IV
25 Ardeola grayii Pond Heron Sch-IV
26 Pavo cristatus Peacock Sch-I
II.Reptiles
1 Calotes versicolor Common garden lizard Sch-IV
2 Chameleon zeylanicus Indian chameleon Sch-IV
3 Bangarus spp. Krait Sch-IV
4 Naja naja Indian cobra Sch-IV
III.Butterflies
1 Pachliopta hector Lin. Crimson rose Sch-IV
2 Papilio demoleu Lime butterfly Sch-IV
3 Junoria almanac Peacock pansy Sch-IV
4 Hypolimnas bolina Great egg fly Sch-IV
5 Euploea core Common crow Sch-IV
6 Neptih hylas moore Common sailor Sch-IV
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Sr. No. Scientific name Common name
Conservation
status as per
WPA (1972)
7 Eurema hecabe Common grass yellow Sch-IV
IV.Amphibians
1 Rana tigrina Bull frog Sch-IV
2 Bufo malanosticus Bufo Sch-IV
V.Mammals
1 Bandicota indica Bandicoot Sch-IV
2 Rhinolopus spp. Bat Sch-IV
3 Hipposiderus spp. Bat Sch-IV
4 Presbytis entellus Langur Sch-II
5 Mucaca mulata Monkey Sch-II
6 Rattus sp. Rat Sch-V
7 Funambulus spp. Squirrel Sch-IV
8 Rattus norvegicus Field mouse Sch-V
9 Lepus nigricollis Hare Sch-IV
10 Rattus rattus House rat Sch-V
3.10.10Aquatic ecosystems
Phytoplankton
Phytoplankton forms the basis of food chain in any aquatic water body. The
diversity and abundance of phytoplankton mainly depends on the region, type of
water body, either lentic or lotic, the nutrient flux in the system and the sunlight
available for photosynthesis. These factors together form the dynamics of
phytoplankton productivity over the seasons. The phytoplankton of given water
body determines the zooplankton populations and the fish productivity of the
ecosystem.
Phytoplankton group reported from the study area were Basillariophyceae,
Chlorophyceae, Myxophyceae and Euglenophyceae members. About 20 species of
phytoplankton were reported from all the locations. Dominance of
Bacillariophyceae members followed by Myxophyceae was observed in studies
samples. The highest percentage was Ankistrodesmus sp. and Navicula sp. and
the lowest percentage was ophora sp and Synedra sp. was observed.
Zooplankton
The zooplankton of the aquatic water body are the primary consumers and also in
cases secondary producers which play an important role for the fisheries of that
system. The diversity and abundance of zooplankton also depends on whether the
water body is eutrophic or oligotrophic. About 14 species of zooplankton were
reported from all the locations. They also are good representatives of the
ecosystem health. The amount and type of pollutants in the water body
determine the type of zooplankton species. Species of copepod will usually
dominate in the tropical region while more eutrophicated waters with high
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nutrient or organic loads will harbor high number of crustaceans and arthropods.
The less polluted waters will have more of cladocerans and rotifers.
Among the zooplankton group, Asplancha sp.had highest percentage composition
and the lowest percentage composition was of Ceriodaphnia sp. in the total
zooplankton. The list of plankton recorded in fresh water bodies in study area
during study period are presented in Table-3.27.
TABLE-3.27
LIST OF PLANKTON RECORDED DURING STUDY PERIOD
Sr. No. Phytoplankton Zooplankton
1 Gyrosigma sp. Keratella monospina
2 Achananthes affinis Brachirous caudatus
3 Gyrosigma accuminatus Asplancha brighwell
4 Pandorina sp. Colpidium colpoda
5 Ankistrodesmus falcatus Daphnia sp.
6 Ankistrodesmus sp. Ceriodaphnia reticulate
7 Pediastrum boryanum Mesocyclops leuckarti
8 Scenedesmus bijuga Mesocyclops hyalinus
9 Melosira granulate Coleps hirsutus
10 Cyclotella meneghiana Arcella sp.
11 Microcystis sp. Actinophyros sp.
12 Navicula gracilis Asplancha sp.
13 Nitzschia gracilis Ceriodaphnia sp.
14 Chroococcus minutes Mesocyclops sp.
15 Spirulina princepes
16 Pinnularia braunii
17 Synedra tabulate
18 Ophora sp.
19 Cymbella sp.
20 Navicula radiosa
Fishes
The Arani River is a perennial river and the list of principle catchers is given in
Table-3.28.
TABLE-3.28
AQUATIC FAUNA FROM STUDY AREA
Sr. No. Local Name Zoological Name
1 Catla Catla catla
2 Rohu Labeo rohita
3 Mrigal Cirrhinus mrigala
4 Silver Carp Thirmethrix molitrix
5 Grass Carp Ctenopheringodon idella
6 Common Carp Cyprinus carpio
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3.10.11Conclusion
From the field observations it can be concluded that the forests in the study area
are under anthropogenic pressure and show signs of degradation in the form of
tree cutting, lopping, grazing and collection of NTFPs and habitat fragmentation.
As per MOEF and Forest Department of Tamilnadu state reveals that there are no
Wildlife sanctuaries, National parks/biosphere reserves in 10 km radius from the
proposed site boundary. As per the records of the Botanical Survey of India there
are no plants of conservation importance in the study area.
It can be concluded that there is one species belonging to Sch-I,2 species belongs
to Sch-II and rest of species belongs Sch-III, Sch-IV and Sch-V of Wildlife Protection
Act, 1972.
3.11 Demography and Socio-Economics
The growth of industrial sectors and infrastructure developments in and around
the agriculture dominant areas, villages and towns are bound to create its impact
on the socio-economic aspects of the local population. The impacts may be
positive or negative depending upon the developmental activity. To assess the
impacts on the socio-economics of the local people, it is necessary to study the
existing socio-economic status of the local population, which will be helpful for
making efforts to further improve the quality of life in the area of study. To study
the socio-economic aspects of people in the study area around the plant site, the
required data has been collected from various secondary sources and
supplemented by the primary data generated through the process of a limited
door to door socio-economic survey.
3.11.1 Methodology adopted for the Study
The methodology adopted for the study is based on the review of secondary data,
such as District Census Statistical Handbooks-2001 of Thiruvallur district and the
records of National Informatics Center, New Delhi, for the parameters of
demography, occupational structure of people within the general study area of
10-km radius around the plant site.
3.11.2 Review of Demographic and Socio-Economic Profile - 2001
The sociological aspects of this study include human settlements, demography,
social such as scheduled castes and scheduled tribes and literacy levels besides
infrastructure facilities available in the study area. The economic aspects include
occupational structure of workers.
The salient features of the demographic and socio-economic details are described
in the following sections.
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3.11.3 Demography
Distribution of Population
As per 2001 census, the study area consists of 2,78,458 persons. The distribution
of population in the study area is given in Table-3.29. The males and females
constitute 50.86 % and 49.14 % of the study area population respectively.
TABLE-3.29 DISTRIBUTION OF POPULATION
Particulars 0-3 km 3 - 7
km
7-10
km 0-10 km
No. of House holds 4532 14927 44845 64304
Male Population 9916 32925 98785 141626
Female Population 9932 31478 95422 136832
Total Population 19848 64403 194207 278458
Avg. House hold size 4.38 4.31 4.33 4.33
Male % 49.96 51.12 50.87 50.86
Female % 50.04 48.88 49.13 49.14
Source: Thiruvallur District Census Statistics-2001
Average Household Size
The average household size of the study area is 4.33. The low family size could
be attributed to a high degree of urbanization with migration of people with
higher literacy levels who generally opt for smaller family size and family welfare
measures.
Sex Ratio
The configuration of male and female indicates that the males constitute to about
50.86% and females to 49.14% of the total population as per 2001 census
records. The sex ratio i.e. the number of females per 1000 males indirectly
reveals certain sociological aspects in relation with female births, infant mortality
among female children and single person family structure, a resultant of
migration of industrial workers. The study area on an average has 966 females
per 1000 males as per 2001 census.
3.11.4 Social Structure
As per 2001 census, the percentage of scheduled caste population is 21.45%
within 10-km radius study area. The percentage of Schedule Tribe population is
1.4%. The distribution of population by social structure is given in Table-3.30.
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TABLE- 3.30
DISTRIBUTION OF POPULATION BY SOCIAL STRUCTURE
Particulars 0-3 km 3 - 7 km 7-10 km 0-10 km
Schedule Caste 5482 14404 39853 59739
% of total population 27.62 22.37 20.52 21.45
Schedule Tribes 634 1390 1758 3782
% of total population 3.2 2.2 0.9 1.4
Total SC and ST population 6116 15794 41611 63521
% To total population 30.81 24.52 21.43 22.81
other caste population 13732 48609 152596 214937.00
% To total population 69.19 75.48 78.57 77.19
Total population 19848 64403 194207 278458
3.11.5 Literacy Levels
The study area experiences a literacy rate of 63.73%. The distribution of literate
and literacy rate in the study area is given in Table-3.31.
The male literacy rate i.e. the percentage of male literates to the total males of
the study area works out to be 57.34%. The female literacy rate, which is an
important indication for social change is observed to be 42.66%.
TABLE 3.31
DISTRIBUTION OF LITERATE AND LITERACY RATES
Particulars 0-3 km 3 - 7 km 7-10 km 0-10 km
Total literate 10873 38594 127983 177450
Male population 9916 32925 98785 141626
Female population 9932 31478 95422 136832
Average literacy (%) 54.78 59.93 65.90 63.73
Male Literate 6347 22769 72632 101748
% To Study area literate 58.37 59.00 56.75 57.34
% To total male population 64.01 69.15 73.53 71.84
Female Literate 4526 15825 55351 75702
% To Study area literate 41.63 41.00 43.25 42.66
% To total female population 45.57 50.27 58.01 55.32
Total Population 19848 64403 194207 278458
3.11.6 Occupational Structure
The occupational structure of residents in the study area is studied with reference
to main workers, marginal workers and non-workers. The main workers include
10 categories of workers defined by the Census Department consisting of
cultivators, agricultural labourers, those engaged in live-stock, forestry, fishing,
mining and quarrying; manufacturing, processing and repairs in household
industry; and other than household industry, construction, trade and commerce,
transport and communication and other services.
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The marginal workers are those workers engaged in some work for a period of
less than six months during the reference year prior to the census survey. The
non-workers include those engaged in unpaid household duties, students, retired
persons, dependents, beggars, vagrants etc.; institutional inmates or all other
non-workers who do not fall under the above categories.
As per 2001 census records, altogether the main worker works out to be 30.71%
of the total population. The marginal workers and non-workers constitute to
8.19% and 61.11% of the total population respectively. The distribution of
workers by occupation indicates that the non-workers are the predominant
population. The occupational structure of the study area is shown in Table-3.32.
The demographic details in the study area are provided as Annexure – 10.
TABLE-3.32
OCCUPATIONAL STRUCTURE
Particulars 0-3 km 3-7 km 7-10 km 0-10 km
Total main workers 5408 22204 57890 85502
% to total population 27.25 34.48 29.81 30.71
Marginal workers 3328 4734 14730 22792
% to total population 16.77 7.35 7.58 8.19
Non-workers 11112 37465 121587 170164
% to total population 55.99 58.17 62.61 61.11
Total Population 19848 64403 194207 278458
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4.0 ANTICIPATED ENVIRONMENTAL IMPACTS AND MITIGATION MEASURES
4.1 Introduction
This chapter presents identification and appraisal of various impacts due to the
proposed expansion of the existing coal based thermal power plant during
erection and operational phases. The environmental impacts are categorized as
primary or secondary. Primary impacts are those, which are attributed directly to
the project and secondary impacts are those, which are indirectly induced and
typically include the associated investment and changed pattern of social and
economic activities by the proposed activity.
The mitigation measures proposed for minimizing the impacts have also been
discussed in this chapter. Environment Management Plan (EMP) is developed to
minimize adverse impacts and to ensure that the environment in and around the
project site is well protected. The EMP has been prepared for both construction
and operation phases of the proposed facilities.
The impacts have been assessed for the power plant assuming that the pollution
due to the existing activities has already been covered under baseline
environmental monitoring and continue to remain same till the operation of the
project.
The erection and operational phase of the proposed expansion project comprises
various activities each of which may have an impact on some or other
environmental parameters. Various impacts during the erection and operation
phase on the environment have been studied to estimate the impacts on the
environmental attributes and are discussed in the subsequent sections.
4.2 Impacts during Construction Phase
This includes the following activities related to land acquisition, leveling of site,
construction of related structures and installation of related equipment.
4.2.1 Impact on Land Use
The existing plant operates in area of 25.49 ha (62.99 acres). The land identified
for the proposed addition of 1 x 350 MW thermal power plant unit is about 11.49
ha (28.39 acres) adjacent to the existing plant site. About 3.25 ha (8.03 acres) of
the land will be used as ash dyke. Main plant facilities and ancillary facilities will
occupy about 12.45 ha (30.76) acres of land.
Entire site (existing & proposed) is under the ownership of the project proponent
and there is no forest or ecological sensitive land within the existing & additional
site. No residential or habitation areas are proposed to be acquired, hence no
displacement of residential areas.
Construction of additional facilities will lead to permanent change in land use
pattern at the proposed adjacent site as a direct impact.
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The proposed expansion involves erection of large scale civil works including
levelling within project premises. The earthen material generated during
construction of additional water storage reservoir within the site premises will be
used for elevating plant area.
The environmental pollution impacts during erection phase would be temporary
and are expected to gradually stabilize by the time of commissioning of proposed
expansion activity.
There are no sensitive locations such as archaeological monuments, sanctuaries,
national parks, critical pollution zones etc., within 10 km radial distance around
the existing plant site. No major changes in land use pattern of study area
(region) will occur due to the project activities.
Hence, no major impact is envisaged on land use pattern of the project site (core
zone) or the buffer zone.
4.2.2 Impact on Soil
The construction activities will result in loss of vegetation cover, topsoil and earthen
material to some extent in the plant area. However, it is proposed to use the soil
and earthen material for greenbelt development and levelling of project site.
Additional greenbelt will be developed in phased manner from erection stage
onwards.
Apart from localized construction impacts at the plant site, no adverse impacts on
soil in the surrounding area are anticipated.
4.2.3 Impact on Topography
The existing plant site is partially plain and undulating with a general elevation of
about 18 m above MSL.
It is proposed to level the additional project site and to use the earthen material
excavated from the proposed additional reservoir inside the premises itself. There
will not be any tall structures except the stacks for plume dispersion. Also, the
contours of natural drainage will not be disturbed.
In view of the above, there will not be any major impacts on topography of the
project site.
4.2.4 Impact on Air Quality
The main sources of emission during the erection period are the movement of
equipment at site and dust emitted during the leveling, grading, earthwork,
foundation works and exhaust emissions from vehicles and equipment deployed
during the construction phase is also likely to result in marginal increase in the
levels of SO2, NOx, PM and CO. The impact will be for short duration and confined
within the project boundary and is expected to be negligible outside the plant
boundaries.
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The impact will, however, be reversible, marginal and temporary in nature. Proper
maintenance of vehicles and construction equipment will help in controlling the
gaseous emissions. Water sprinkling on roads and construction site will prevent
fugitive dust.
4.2.5 Impact on Water Quality
Impact on water quality during erection phase may be due to non-point discharge of
solids from soil loss and sewage generated from the construction workforce
stationed at the site. Further, the construction will be more related to mechanical
fabrication, assembly and erection; hence the water requirements would be small.
Sanitary sewage generated by the temporary workforce will be handled by the
existing STP itself.
The overall impact on water environment during erection phase due is likely to be
short term and insignificant.
4.2.6 Impact on Noise Levels
Vehicular traffic, loading and unloading of construction material, fabrication and
handling of equipment and materials are likely to cause an increase in the ambient
noise levels. The areas affected are those close to the site. However, the noise will
be temporary and will be restricted mostly within plant area.
The noise control measures during erection phase include provision of caps on the
equipment and regular maintenance of the equipment.
4.2.7 Impact on Terrestrial Ecology
The land required for the expansion of power plant is a Barren land and cutting of
trees are not required. Therefore, no major loss of biomass is envisaged during
construction phase. Although the land required for the expansion of the plant
would be put to industrial use, there may not be any significant impact on soil
and agriculture in general. These impacts are, however, restricted to the early
phase of construction.
The removal of herbaceous vegetation from the soil and loosening of the topsoil
generally causes soil erosion during dry season. However, such impacts would be
primarily confined to the project site during initial periods of the construction
phase and would be minimized through adoption of mitigatory measures like
paving and surface treatment, water sprinkling and appropriate plantation
program. The project site and township area will be extensively landscaped with
the development of green belt consisting of a variety of taxa, which would enrich
the ecology of the area and add to the aesthetics.
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4.3 Impacts during Operational Phase
The expansion activity will involve a proposed power generation of 485 MW (1 x
135 MW + 1 x 350 MW) of power generation in addition to the existing 60 MW.
The following activities related to the operational phase will have varying impacts
on the environment and are considered for impact assessment:
Topography and climate;
Air Environment;
Water resources and quality;
Land use;
Soil quality;
Solid waste;
Noise levels;
Terrestrial and aquatic ecology;
Demography and socio-economics; and
Infrastructural facilities.
4.3.1 Topography
Most of the area of the plant site is partially plain with slight undulations and it will
be maintained plain during post-project scenario. There will not be any
topographical changes during operation of the project.
4.3.2 Impact on Air Quality – Point Sources
Being a coal based thermal power project, the important air pollutants are
Sulphur dioxide (SO2), Oxides of Nitrogen (NOx) and Particulate Matter (PM).
Prediction of impacts on air environment has been carried out by employing
mathematical model based on a steady state Gaussian plume dispersion model
designed for multiple point sources for short term. In the present case, AERMOD -
designed for multiple point sources for short term and developed by United States
Environmental Protection Agency [USEPA] has been used for simulations from point
sources.
The model simulations deal with dispersion of three major pollutants viz., Sulphur
Dioxide (SO2), Oxides of Nitrogen (NOx) and Particulate Matter (PM) emitted from
the stacks.
4.3.2.1Air Pollution Impact Prediction through Modelling
a. AERMOD View
AERMOD is an air dispersion-modeling package, which seamlessly incorporates
the popular USEPA Models, ISCST3, ISC-PRIME and AERMOD into one interface
without any modifications to the models. These models are used extensively to
assess pollution concentration and deposition from a wide variety of sources.
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b. AERMOD Model
The AMS/EPA REGULATORY MODEL (AERMOD) was specially designed to support
the Environmental Regulatory Modeling Programs. AERMOD is a regulatory steady
– state-modeling system with three separate components;
AERMOD (AERMIC Dispersion Model);
AERMAP (AERMOD Terrain Preprocessor); and
AERMET (AERMOD) Meteorological Preprocessor.
The AERMOD model includes a wide range of options for modeling air quality
impacts of pollution sources, making it popular choice among the modeling
community for a variety of applications. AERMOD requires two types of
meteorological data files, a file containing surface scalar parameters and a file
containing vertical profiles. These two files are provided by AERMET
meteorological pre-processor program.
PRIME building downwash algorithms based on the ISC – PRIME model have
been added to the AERMOD model;
Use of arrays for data storage;
Incorporation of EVENT processing for analyzing short-term source culpability;
Explicit treatment of multiple – year meteorological data files and the annual
average; and
Options to specify emissions that vary by season, hour-of-day and day-of-
week.
Deposition algorithms have been implemented in the AERMOD model – results
can be output for concentration, total deposition flux, dry deposition flux, and / or
wet deposition flux. The model contains algorithms for modeling the effects of
settling and removal of large particulates and for modeling the effects of
precipitation scavenging for gases or particulates.
c. AERMET
In order to conduct a refined air dispersion modeling project using the AERMOD
short-term air quality dispersion model, it is necessary to process the
meteorological data representative of the study area being modeled. The
collected meteorological data is not always in the format supported by the model,
therefore the meteorological data needs to be pre-processed using AERMET
program.
The AERMET program is a meteorological preprocessor, which prepares hourly
surface data and upper air data for use in the AERMOD air quality dispersion
model. AERMET is designed to allow future enhancements to process other types
of data and to compute boundary layer parameters with different algorithms.
AERMET processes meteorological data in three stages and from this process two
files are generated for use with the AERMOD model.
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A surface file of hourly boundary layer parameters estimates a profile file of
multiple-level observations of wind speed, wind direction, temperature and
standard deviation of the fluctuating wind components.
d. Application of AERMOD
AERMOD model with the following options has been employed to predict the
cumulative ground level concentrations due to emissions from the proposed
activity.
All terrain dispersion parameters are considered;
Predictions have been carried out to estimate concentration values over radial
distance of 10 km around the project area;
Uniform polar receptor network has been considered;
Emission rates from the sources were considered as constant during the entire
period;
The ground level concentrations computed without any consideration of decay
coefficient;
Calm winds recorded during the study period were also taken into
consideration;
24 hourly mean ground level concentrations were estimated using the entire
meteorological data collected during the study period; and
The study area is used to represent the graphical output of the GLC’s using the
terrain processor.
e. Meteorological Data
The hourly meteorological data recorded at site is converted to the mean hourly
meteorological data as specified by CPCB and the same has been used in the
model. Hourly mixing heights are taken from the “Atlas of Hourly Mixing Height
and Assimilative Capacity of Atmosphere in India” published by India
meteorological department, 2008, New Delhi.
The meteorological data recorded during study period continuously on wind speed,
wind direction, temperature etc., have been processed to extract the data required
for simulation by AERMOD using AERMET. The meteorological data used are given
in Table 4.1.
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TABLE-4.1
HOURLY MEAN METEOROLOGICAL DATA
Time in
hours
Wind speed in
m/s
Wind
direction in
degrees
Air Temperature
in K
Stability
class
Mixing
height
in m
12:10:00 AM 3.258 180 303.15 1 1000
01:10:00 AM 3.861 247.5 303.15 1 1000
02:10:00 AM 3.494 202.5 303.15 1 1000
03:10:00 AM 4.111 225 303.15 1 1000
04:10:00 AM 2.314 225 303.15 2 1000
05:10:00 AM 3.481 247.5 303.15 2 900
06:10:00 AM 3.306 270 303.15 1 800
07:10:00 AM 3.347 270 304.15 4 800
08:10:00 AM 4.939 247.5 306.15 4 200
09:10:00 AM 3.944 270 306.15 6 200
10:10:00 AM 5.139 270 309.15 6 200
11:10:00 AM 4.453 270 310.15 6 200
12:10:00 PM 4.639 270 310.15 6 200
01:10:00 PM 4.111 270 309.15 6 200
02:10:00 PM 5.792 270 309.15 6 200
03:10:00 PM 4.117 90 309.15 6 200
04:10:00 PM 4.375 112.5 307.15 6 200
05:10:00 PM 4.375 135 306.15 6 200
06:10:00 PM 3.347 135 305.15 6 500
07:10:00 PM 4.328 135 305.15 6 800
08:10:00 PM 5.139 157.5 304.15 6 800
09:10:00 PM 3.861 180 304.15 4 800
10:10:00 PM 4.375 180 304.15 1 800
11:10:00 PM 3.731 180 304.15 1 1000
f. Emission Factors Considered in Model
The modelling has been carried to predict the impacts of the power generation
operations with a total generation capacity of 545 MW, considering emission
factors for the worst case i.e. without control measures. The emission factor has
been estimated for 2 nos. of point sources as given in Table-4.2. The graphical
representation of ground level concentrations (GLCs) is shown in Figure-4.1
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TABLE-4.2
STACK DETAILS
Particulars Existing Proposed
Stack 1 Stack 2
Material of Construction RCC RCC
Stack attached to 1 x 60 MW & 1 x 135 MW
1 x 350 MW
Stack height (m) 145 220
Stack diameter (mm) approx. 5250 6500
Volume Flow Rate (m3/s) 475.45 696.82
Velocity of flue gas (m/s) 22.0 21.0
Temperature of flue gas (°C) 140 140
Flue gas specific volume (kg/Nm³) 1.3 1.3
Fuel Consumption (Kg/s) 34.17 55.09
Sulphur content (% w/w) 0.5 0.5
Emission rate – NOx (g/s) 307.5 495.83
Emission rate – SO2 (g/s) 341.67 550.925
Emission rate – PM (g/s) 21.5 34.841
g. Presentation of Results
The model simulations have been carried out for pre monsoon season. For the
short-term simulations, the ground level concentrations (GLCs) were estimated
around 220 receptors to obtain an optimum description of variations in
concentrations over the site in 5 km radius covering 16 directions.
The maximum incremental ground level concentrations and resultant concentrations
for PM, SO2 and NOx are given in Table-4.3 and Table-4.4 respectively. Similarly,
the isopleths for various pollutant concentrations are enclosed. The CPCB
permissible ambient air quality standards are given in Table-4.4.
TABLE-4.3
PREDICTED 24-HOURLY SHORT TERM INCREMENTAL CONCENTRATIONS
Season Maximum Incremental GLCs
( g/m3) Distance
(km) Direction
Pre-monsoon 2014 PM SO2 NOx
Imported coal 1.39 22.14 15.66 2.0 East
TABLE-4.4
RESULTANT CONCENTRATIONS DUE TO INCREMENTAL GLC's
(WORST CASE SCENARIO)
Pollutant Concentration ( g/m3)
Standards Baseline Incremental Resultant
PM 83.1 1.39 84.49 100
SO2 26.9 22.14 49.04 80
NOx 33.2 15.66 48.86 80
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h. Discussions on Results of Assessment
A perusal of previous sub-section reveal that the maximum incremental short-term
24 hourly ground level concentrations for PM, SO2 and NOx likely to be encountered
in the operation of the power project are 1.39, 22.14 and 15.66 g/m3 respectively
occurring at a distance of about 2.0 km in the East direction.
The worst case maximum resultant 24 Hourly concentrations for PM, SO2 and NOx
after implementation of the proposed activity are 84.49, 49.04 and 48.86 µg/m3
respectively.
According to the above presented results, it can be stated that the impact of PM
from proposed expansion would be negligible in core or buffer zone of the project.
Even though, the incremental and resultant concentrations of SO2 and NOx are
significant to certain extent, they are well within the NAAQ limits and hence, the
AAQ levels after implementation of the proposed activity will remain within the
permissible limits. Hence, it can be stated that the AAQ of the area will be within
the permissible limits of respective zones.
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FIGURE-4.1
SHORT TERM 24 HOURLY INCREMENTAL GLCs OF PM
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FIGURE-4.2
SHORT TERM 24 HOURLY INCREMENTAL GLCs of SO2
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FIGURE-4.3
SHORT TERM 24 HOURLY INCREMENTAL GLCs of NOx
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4.3.3 Impact on Air Quality - Fugitive Emissions
The fugitive dust emissions expected are from coal storage yards, coal conveyor
belt area, ash dumping areas, transportation of fuel and solid waste.
Coal handling unit will be properly operated with EMP suggested in this report, no
major fugitive dust emissions are envisaged. Similarly, HCSD system of ash
stacking will be practiced and hence, no dust emissions are envisaged from ash
dump areas. The fuel will be conveyed through belts and the solid waste will be
sent to dyke areas through pipeline. Hence, no dust emissions from handling are
envisaged. However, internal roads are to be asphalted to further reduce fugitive
dust emissions.
The dust emissions, if any, from the above areas will be fugitive in nature and
maximum during summer season (when the wind velocities are likely to be high)
and almost nil during the monsoon season. The dust emissions are likely to be
confined to the place of generation only. The quantification of these fugitive
emissions from the area sources is difficult as it depends on lot of factors such as
dust particle size, specific gravity of dust particles, wind velocity, moisture content
of the material and ambient temperatures etc. Also, there is a high level of
variability in these factors. Hence, these are not amenable for mathematical
dispersion modelling. However, by proper usage of dust suppression measures,
dust generation and dispersions will be reduced.
The impact of fugitive dust emissions from the proposed units on air quality of the
region is insignificant.
4.3.4 Impact on Water Resources and Water Quality
The entire water demand for the existing and the proposed facilities will be met
from the existing borewell within plant site. However, the impact on ground water
level will be mitigated by adopting suitable rain water harvesting and ground
water recharge measures. Ground water uptake will be limited by using rain
water collected in a huge rain water harvesting pond with a collection capacity of
70 MLD. Additionally, a new rain water collection pond is also proposed for the
expansion activity.
4.3.4.1 Impact on Water Quality
The water balance and wastewater generation details have been described in
Chapter-2. Total wastewater (including domestic wastewater) generation in the
project will be about 216.8 m3/day. Out of 216.8 m3/day of wastewater
generated, about 160.16 m3/day will be re-used for boiler make-up. About 43.84
m3/day will be used for ash quenching & coal dust suppression and the remaining
12.8 m3/day will be used for greenbelt development.
Garland drains around the ash dyke site will be provided for the collection of run-
off water during monsoon season.
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The storm water in the project area will be collected through storm water drains
and collected in the rain water collection pond, which is lined to prevent any
contamination of ground water. The stored storm water will be utilized in the
plant operation resulting in conservation of fresh water.
Various types of wastewater to be generated from the plant with their quantity,
expected pollutants and their respective treatment are provided in Table-4.5.
TABLE-4.5
TYPE OF WASTEWATER GENERATION AND TREATMENT DETAILS
Sources of wastewater Treatment & Disposal
Runoff Water From Coal Yard
The runoff from the coal yard will be collected in a settling tank. The clear water will be taken to a collection tank and used for watering of green belt
Runoff Water From Limestone Yard
The runoff from the limestone yard will be collected in a settling tank. The clear water
will be taken to a collection tank and used for watering of green belt
Neutralized Waste Water Make-up water treatment plant waste will be taken to separate neutralization pit, neutralized and then pumped to the Common Monitoring
Basin (CMB)
Oily Waste Water Oil bearing effluent generated from fuel oil handling area plant floor wash etc. will be treated in an oil/water separator to separate oil from water and the treated waste water sent to CMB. The oily sludge will be collected
and disposed offsite
Sewage Water from Toilets in the Power Plant
The Sewage water generated from the Power Plant will be treated in an anaerobic filter and the treated effluent will be collected and used for horticulture. Suitable arrangements for
collection of sludge, its compaction and safe disposal will be provided
Boiler Blow Down Boiler blow down waste water will be fed to neutralization pit of water treatment plant and from there it will be sent CMB
Special Waste Water Special waste water like Air Preheater washing water, acid cleaning of boiler etc. will be collected and treated in a chemical waste cleaning plant to make it suitable for offsite disposal
Clarifier Sludge The sludge collected in the clarifier will be taken to a sedimentation tank and the clear water
will be sent to CMB. The collected sludge will be taken to a sludge drying bed and spread over the green belt within the plant boundaries
Common Monitoring
Basin
The outlet from the CMB after ensuring that
the quality meets the requirements stipulated in the PCB norms, will be used for coal yard dust suppression, limestone dust suppression and watering of green belt
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The expected quality of raw and treated wastewater from the power plant
including sewage water and discharge limits as specified by environment
protection rules is given in Table-4.6.
TABLE-4.6
EXPECTED QUALITY OF WASTEWATER
Sr. No. Parameter Unit Raw wastewater Treated
Wastewater
Permissible Limits as per GSR 422 (E) for On-land
Discharge (Irrigation)
1 pH - 5.5 to 9.0 6.0 to 8.5 5.5 to 9.0
2 Suspended Solids mg/l 100 to 500 <100 200
3 Oil & Grease mg/l 10 to 200 <5 10
4 Total Dissolved Solids mg/l 500 to 10000 <1000 --
5 BOD mg/l 250 to 350 <30 100
6 COD mg/l 450 to 600 <100 -
7 Zinc mg/l 1 to 5 <1 -
Entire treated wastewater will be reused / recycled and zero discharge from the
plant will be ensured. Thus, no impact on the natural water bodies is envisaged.
4.3.5 Impact on Land Use
The land additionally procured for the proposed 1 x 350 MW unit is about 11.49
ha (28.39 acres). About 3.25 ha of the land will be used for ash disposal.
Greenbelt including existing green cover will be developed in an area of about
13.30 ha (32.86 acres) covering 35.96% of the total plant area upon expansion.
The additional greenbelt proposed will have a positive impact on land. There will be
minimum changes in land use during the operational phase of the project. Hence,
no major impacts are envisaged during operational phase of the project.
4.3.6 Impact on Soil
Most of the impacts of power plant project on soil quality are restricted to the
erection phase, which will get stabilized during operational phase. The impact on the
topsoil will be confined to the main plant area. Further, the additional greenbelt
proposed will have a very positive impact on soil quality.
The probable sources of degradation of soil quality will be due to generation &
disposal of ash and fugitive dust emissions. However, the impacts due to disposal of
ash are covered under Section-4.3.7.
The airborne fugitive dust from the plant is likely to be deposited on the topsoil in
the immediate vicinity of the plant boundary. However, the fugitive emissions are
likely to be controlled to a great extent through proposed control measures like
water sprinkling and development of greenbelt development.
Hence, no impact is envisaged on soil quality of the project site.
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4.3.7 Impact of Solid Wastes
Ash is the major solid waste to be generated from a coal based thermal power
plant. Coal consumption of 2.31 MTPA having 9.0% ash content was considered
for estimation of ash generation. Ash will be generated as both forms viz. bottom
ash and fly ash. About 80% of the total ash generations will be fly ash and
remaining 20% comes as bottom ash. The fly ash is the important air pollutant,
which emits to outside environment through stacks attached to boilers. ESPs with
efficiencies over 99.99% shall be provided to prevent ash dispersions into
ambient air. The details of the solid waste generation are given in Table-4.7.
TABLE-4.7
EXPECTED SOLID WASTE FROM POWER PLANT
Sr. No. Plant Quantity of Generation Mode of Disposal
1 Ash* Fly ash Bottom ash
0.135 MTPA 0.108 MTPA 0.027 MTPA
Emphasis will be given for supply to potential users in dry from. Remaining ash will be disposed into HDPE lined ash dyke through HCSD method
2 Used Oil 2000 KLPA Will be supplied to authorized recyclers
3 Sewage sludge 2.4 TPA Sent to sludge drying beds and used as manure
4 Domestic solid waste / municipal solid waste
5.25 TPA Organic portion will be dried, composted and used as manure. Inorganic portion will be handed to authorised recyclers
* Ash calculations are based the 9% ash content of Indonesian coal considering worst case
Fly ash will be collected from ESP hoppers in dry from and supplied to potential
ash users depending on the demand. The balance unutilized ash will be disposed
of using High Concentrated Slurry Disposal (HCSD) technology. An area of about
2.61 ha has been identified for ash dyke in addition to the existing ash dyke of
0.64 ha within the project premises. In view of the proposed HCSD ash disposal
technology, the impact of ash dyke supernatant runoff would not be expected and
the impacts on surrounding environment would be insignificant. However, it is
also proposed to provide the ash dyke with an impervious HDPE layers.
The sludge from sewage treatment plant will be dried, vermi-composted and used
as manure for greenbelt maintenance. Canteen/sanitary waste will be composted
and used as manure for greenbelt development.
With the implementation of above precautionary measures, the impacts due to
solid waste disposal will be minimum.
Impact of Ash Dyke on Surface Water
In ash disposal, High Concentration slurry disposal method will be adopted. The
bottom ash slurry and fly ash slurry from the both the units will be led to common
slurry sump of the combined ash slurry disposal pump house. In view of the
proposed HCSD ash disposal technology, the impact of ash dyke supernatant run
off would not be expected. Hence, the impact of the ash dyke on the surface water
will be insignificant.
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Impact of Ash Dyke on Ground Water
The possibility of groundwater contamination due to the leaching of metals from
the ash dyke will be examined based on soil investigation study. Fortification
around the dyke will be provided with proper compaction at maximum dry density.
The co-efficient of permeability will be much less than the natural deposits to
further reduce the drainability. However, with the passage of time, more and more
fly ash particles will get deposited in the pore spaces of the top soil making it
essentially non-porous and impervious and in view of the above, contamination
through leaching is not envisaged. However, it is also proposed to provide the ash
dyke with an impervious bottom HDPE layers.
In view of the above mitigative measures, no surface water or groundwater
pollution is anticipated from the ash disposal area. Similarly, as the other solid
wastes also used properly, no impact of solid waste is envisaged.
4.3.8 Impacts on Ecology
Detailed flora and fauna studies were carried out during study period and the
details are presented in Section-3.10 of Chapter-3. As per records of forest
department of Thiruvallur district, literature survey and also from field studies,
there are no endangered, threatened and protected plants as per Wildlife
Protection Act, 1972.
It is proposed to develop additional greenbelt with an average width of about 50
m to 100 m around plant site and implementation of eco development along with
local people will enhance the greenery of the area. Hence, no significant adverse
impact is envisaged on terrestrial ecology.
The impacts on aquatic ecology due to proposed expansion activity would be
negligible as the treated effluents from the plant will meet the prescribed standards
prior to final discharge. Similarly, as the discharge water will not have much higher
temperature than the receiving body, no thermal effects on receiving body due to
discharge are envisaged. Hence, the impacts on ecology of the region will be
insignificant.
4.3.9 Impact on Noise Levels
The main noise generating stationary sources from the power plant will be
pumps, compressors and boilers. The noise levels at the source for these units
will be in the range of 80-90 dB(A). The noise dispersion from the plant units has
been computed based on the mathematical model. The major noise generating
sources from the plant are identified and listed in Table-4.8. These are
considered as input to the noise model.
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TABLE-4.8
MAJOR NOISE GENERATING SOURCES
Sr. No. Sources Noise Level in dB(A)
[1.0 m away] Nature of Noise
1 Turbine units 85 Continuous
2 Air compressors 85 Continuous
3 Transformer 75 Continuous
4 Boilers 85 Continuous
4.3.9.1 Presentation of Results
The incremental noise levels are computed at plant site at 100 m X 100 m grid
intervals over an area of 10 km X 10 km study area. The predicted results of
incremental noise levels at each grid points are used to draw noise contours. The
predicted noise contours around expected sources are shown in Figure-4.4.
The predicted noise levels at the boundary due to various plant activities will be
ranging in between 32 to 36 dB(A). The incremental noise levels will be less than
40 dB(A) at all the surrounding habitations. It is seen from the simulation results
that the incremental noise levels will be well within the CPCB standards.
4.3.9.2 Impact on Work Zone
Boilers are the high noise generating equipment in the existing & the proposed
units. However, impacts on the working personnel are not expected to be
significant on account of the high level of automation of the plant, which means
that workers will be exposed for short duration only.
The noise generation during operational phase would be at source itself through
different measures such as inspection, operation and maintenance at regular
intervals. The noise control measures as described in EMP will be fully followed.
The occupational noise exposure to the workers in the form of 8 hourly time
weighted average will be maintained well within the prescribed OSHA standards
[<90 dB (A)]. Hence, the impact on occupational health of workers would be
insignificant.
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FIGURE-4.4
PREDICTED NOISE DISPERSION CONTOURS
-1000 -800 -600 -400 -200 0 200 400 600 800 1000
-1000 -800 -600 -400 -200 0 200 400 600 800 1000
-1000
-800
-600
-400
-200
0
200
400
600
800
1000
-1000
-800
-600
-400
-200
0
200
400
600
800
1000
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4.3.9.3 Impact on Community
As per the location of power plant, the minimum distance maintained between
existing & proposed major noise sources and the outer periphery of the project
site will be more than 500 m. The cumulative incremental impact of all noise
sources at boundary will range in between 32 to 36 dB (A).
4.3.10 Prediction of Impacts on Socio-Economics
No shifting of human habitations are envisaged for siting of the proposed units,
as the land is a barren land which has been acquired by the proponent. Hence, no
resettlement activities are envisaged.
Unskilled manpower will be met from nearby villages during erection phase. The
project will also help in generation of the indirect employment apart from direct
employment. This will be a positive socio-economic development for the region.
There will be a general upliftment of standard of living in the region.
4.3.11 Impacts on Public Health and Safety
The discharge of waste materials (stack emission, wastewater and solid wastes)
from process operations may have potential impact on public safety and health.
The wastewater generated from power plant will be treated before discharging
outside. It is proposed to reuse the wastewater to the maximum extent. Since,
the adverse impacts on ambient air and soil quality are predicted to be low it is
anticipated that with effective implementation of control measures suggested for
pollution control, the impact on public health will be minimum.
4.4 Environment Management Plan during Erection Phase
During erection phase, the construction activities like site levelling, grading,
transportation of the construction material cause various impacts on the
surroundings. However, the erectional phase impacts are temporary and localised
phenomena except the permanent change in local landscape and land use pattern of
the project site.
4.4.1 Land Environment Management
Preparation of site will involve excavations and fillings. The earthen material
generated during excavations and site grading periods, shall be properly dumped
and slope stabilisation shall be taken. The topsoil generated during erections shall
be preserved and reused for plantations.
No nallas or water courses are present in the project site. The nearest river (R.
Arani) is at about 7.4 km, SSE from the plant site. However, natural drainage
pattern shall not be disturbed as far as possible.
The additional greenbelt area shall be delineated before start-up of earthwork and
tree plantation shall be taken up during erection stage itself.
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4.4.2 Air Quality Management
The activities like site development, grading and vehicular traffic contribute to
increase in PM and NOx concentrations. The mitigation measures recommended to
minimize the impacts are:
Water sprinkling in construction area;
Asphalting the main approach road;
Proper maintenance of vehicles and construction equipment; and
Tree plantation in the area earmarked for greenbelt development.
4.4.3 Water Quality Management
The soil erosion at site during heavy precipitation contributes to the increase in
suspended solids. The wastewater from vehicle and construction equipment
maintenance centre will contribute to oil and grease concentration. The wastewater
from labour colony will contribute to higher BOD concentrations. The mitigation
measures recommended to minimize the impacts are:
Sedimentation tank to retain the solids from run-off water;
Oil and grease trap at equipment maintenance centre;
Packaged STP / septic tanks to treat sanitary waste at labour colony; and
Utilizing the wastewater in greenbelt development.
4.4.4 Noise Level Management
Operation of construction equipment and vehicular traffic contribute to the increased
noise level. Recommended mitigation measures are:
Enclosures for noise making units like pumps, compressors, etc.;
Good maintenance of vehicles and construction equipment;
Plantation of trees around the plant boundary to attenuate the noise; and
Provision of earplugs and earmuffs to workers.
4.4.5 Ecological Management
Clearing of vegetation will not be required as the additional land acquired is a barren
land. Thus, there will not be any ecological impact due to the project in its erection
stage. Furthermore, additional greenbelt with a vegetation density of over 2500
trees/ha has been planned which has a positive impact on the site ecology.
4.5 Environment Management Plan during Operation Phase
During operation phase, the impacts on the various environmental attributes should
be mitigated using appropriate pollution control equipment. The Environment
Management Plan prepared for the proposed expansion project aims at minimizing
the pollution at the source itself.
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4.5.1 Air Pollution Management
Fugitive and stack emissions from the power plant will contribute to increase in
concentrations of PM, SO2, NOx and HCs. The mitigative measures recommended for
the plant are:
Installation of ESP of efficiency more than 99.90% to limit the PM concentrations
below 50 mg/Nm3;
Provision of stack of 220 m height for wider dispersion of gaseous emissions;
Provision of water sprinkling system at raw material storage yard;
Asphalting of the roads within the plant area;
Provision of dust extraction systems at dust generating source.
Developing of greenbelt around the plant to arrest the fugitive emissions;
Online flue gas monitors as well as flue gas flow rates and temperature
measurement shall be provided for all stacks; and
Usage of washed / beneficiated coal may be explored.
The fugitive dust emissions shall be controlled by installation of closed conveyor
system along with suitable dust suppression measures.
4.5.2 Water Pollution Management
Wastewater will be generated from boilers & DM plant from the project. Besides,
domestic wastewater from canteen and employees wash area will also be
generated. The recommended measures to minimise the impacts and conservation
of fresh water are:
Recycling of wastewater for ash disposal, coal handling and service water
requirements;
The effluent carrying oil spillage in the plant area shall be sent to oil-water
separator for removal of oil;
Coal stock piles and ash dyke shall be provided with garland drains and water
shall be treated for suspended / floating solids;
Adequate treatment of wastewater prior to recycling/reuse to maximum extent;
Provision of sewage treatment plant to treat domestic sewage generated from
plant;
Utilization of treated domestic wastewater in toilet flushing & greenbelt
development;
Lining of effluent dyke suitably to prevent any seepage into ground to avoid any
groundwater contamination;
Provision of storm water system to collect and store run-off water during rainy
season and utilization of the same in the process to reduce the fresh water
requirement;
Suitable rainwater harvesting structures to be constructed.
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4.5.3 Rainwater Harvesting System
Rainwater harvesting structures will be provided to recharge the groundwater
resources in the region. The run-off water from the roof of the structures and
paved areas shall be collected through storm water drainage system and led to
rain water harvesting structure.
4.5.4 Noise Pollution Management
In the process, various equipments like pumps, compressors etc., generate noise.
The recommendations to mitigate higher noise levels are:
Equipments should be designed to conform to noise levels prescribed by
regulatory authorities;
Provision of acoustic barriers or shelters in noisy workplaces;
Provision of hoods to noise generating equipment like pumps;
Provision of thick greenbelt to attenuate noise levels;
Provision of Personal Protective Equipments (PPE) such as earplugs, earmuffs to
the workers working in high noise level area; and
Implementation of greenbelt, landscaping with horticulture at power block areas
to reduce noise impacts.
4.5.5 Solid Waste Management
Solid waste in the form of ash will be generated in a coal based thermal power
plant. The total ash generated in the plant will be 0.135 MTPA out of which 80%
will be fly ash i.e. 0.108 MTPA and balance will be bottom ash of 0.027 MTPA. The
following measures shall be taken for solid waste management:
In general, ash will be given to potential ash users;
The excess ash will be disposed of using high concentrated slurry disposal
system to HDPE lined ash dyke;
The generated waste oil shall be explored to be used in boiler furnace with HFO
or shall be given to authorized recyclers;
Solid waste generated in the Sewage Treatment Plant (STP) will be used as
manure in greenbelt development; and
Maintaining the data base on solid waste generation such as quantity, quality,
treatment / management.
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4.5.5.1 Literature on Fly Ash Utilization
Fly Ash use in Cement Industries
Cement mixed with fly ash is known as Portland Pozzolana Cement (PPC). As per
the Indian standards, fly ash can be used to replace 25% to 35% cement. The fly
ash cement is made by grinding with clinker. The fly ash generated from plant will
be supplied to cement plants in the region. The fly ash can be utilized by these
cement plants to manufacture PPC cement.
Fly Ash use in Road Construction
Fly ash can be used as a component in a stabilized aggregate sub-base course. A
blend of 84% dense aggregate, 11% fly ash and 5% hydrated lime gives
maximum dry density, optimum moisture content and unconfined compressive
strength.
4.5.5.2 Prospective Ash Utilization
It is very much clear that the ash generated at the power plants can be
effectively used for various products. Though the acceptability of the ash-based
products may take a long time, it is always better to start on a small scale.
The figures derived at about the ash utilization in the area are only rough
estimates and may be considered as a guideline. The probable ash utilization
quantities estimated in the earlier sections are tabulated in the following Table-
4.9.
TABLE-4.9
SELECTED AREAS OF FLY ASH UTILIZATION
All values except percentage are in MTPA
Sr. No. Item Description 1st
year 2nd
year 3rd
year 4th
year
1 Total production of fly ash 1.00 1.00 1.00 1.00
2 Use in brick plants 0.01 0.01 0.01 0.01
3 Fly ash use in micro nutrition as fertilizers 0.01 0.01 0.01 0.01
4 Use in fly ash in clay brick 0.02 0.02 0.03 0.14
5 Road development in surrounding areas 0.01 0.01 0 0
6 Use of pozzolonic material cement (PPC) 0.63 0.72 0.79 0.83
7 Total fly ash consumption 0.68 0.78 0.84 1.00
8 Percentage of use of fly ash (%) 68 78 84 100
Note: The figures derived above the ash utilization in the area are only rough estimates and may be considered as a guideline only.
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4.5.5.3 Policy on Fly Ash Utilization
Utilization of ash produced by coal based power stations as a thrust area of its
activities and all possible actions will be taken to enhance level of ash utilization.
Various avenues for ash utilization will be explored as delineated in the above
sections. In particular, supply of quality ash for manufacture of cement will be
taken as there are some cement units. Some of the actions planned for the
project are as given below:
ARS will make efforts to motivate and encourage entrepreneurs to set up
units for manufacture of ash-based products such as fly ash bricks,
lightweight aggregates, cellular concrete products etc., as ancillary industries
in the region. ARS would be providing all possible infrastructure facilities to
these entrepreneurs in accordance with its policy;
ARS will also continue to encourage utilization of available ash based products
in all its erection activities; and
ARS will encourage the use of water treated fly ash as a soil ameliorator and
as a source of micro-nutrients and secondary nutrients for improving
agricultural productivity.
All efforts will be made for 100% utilization of fly ash.
ARS is committed to comply with the Fly Ash Utilization Notification, 1999 and as
amended thereof.
4.5.5.4Excess ash Disposal
The balance ash after utilisation shall be disposed in ash dyke. Ash disposal system
proposed is High Concentrate Slurry Disposal (HCSD). Treated wastewater will be
used in ash handling plant. The ash dyke will be provided with HDPE liners. The area
provided for ash dyke is about 3.25 ha.
The major advantages of the HCSD method are:
Very low water consumption;
The slurry can be self-setting and self-limiting so that ash will deposit and dry
by itself to form a hard surface;
Considerably less area is required for ash disposal;
Specific energy consumption in pumping and transportation will be much
lower;
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Pipeline diameter can be much smaller and transportation velocities could also
be considerably lower due to the fact that the slurry is non-settling. This could
also reduce wear in the pipeline;
Both bottom ash and fly ash can be disposed together if needed; and
The trenches will be constructed along the periphery of the ash dyke to collect
the run-off water during rainy days. The run-off water will be routed through
sedimentation tank before discharging.
The ash will be utilized in various construction materials to the maximum extent and
100% utilization will be achieved.
4.6 Greenbelt Development
With rapid industrialization and consequent deleterious impact of pollutants on
environment, values of environmental protection offered by trees are becoming
clear. Trees are very suitable for detecting, recognizing and reducing air pollution
effects. Monitoring of biological effects of air pollutant by the use of plants as
indicators has been applied on local, regional and national scale. Trees function as
sinks of air pollutants, besides their bio-esthetical values, owing to its large
surface area.
The greenbelt development not only functions as foreground and background
landscape features resulting in harmonizing and amalgamating the physical
structures of the plant with surrounding environment, but also acts as pollution
sink. Thus, implementation of afforestation program is of paramount importance.
It will also check soil erosion, make the ecosystem more complex and functionally
more stable and make the climate more conducive.
The existing plant has a greenbelt area of 10.33 ha (25.53 acres). Additionally
2.97 ha (7.34 acres) of greenbelt will be developed for the expansion. Greenbelt
with a width of 50 m to 100 m will be developed around the proposed plant site.
The total greenbelt around the power plant complex will be about 13.30 ha
(32.86 acres) covering 35.96% of the total plant area after expansion .
4.6.1 Species for Plantation
The species proposed will have broad leaves. Trees will be selected based on the
type of pollutants, their intensity, location, easy availability and suitability to the
local climate. They have different morphological, physiological and bio-chemical
mechanism/ characters like branching habits, leaf arrangement, size, shape,
surface (smooth/hairy), presence or absence of trichomes, stomatal conductivity
proline content, ascorbic acid content, cationic peroxides and sulphite oxidize
activities etc., to trap or reduce the pollutants.
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Species to be selected will fulfil the following specific requirements of the area:
Tolerance to specific conditions or alternatively wide adaptability to eco-
physiological conditions;
Rapid growth;
Capacity to endure water stress and climate extremes after initial
establishment;
Differences in height and growth habits;
Pleasing appearances; and
Providing shade.
4.7 Cost Provision for Environmental Measures
It is proposed to invest about INR. 360 Crores in addition to the existing facilities
on pollution control, treatment and monitoring systems for proposed activity. In
addition to this, INR. 1.0 Crores per annum will be spent on greenbelt
maintenance in and around the proposed additional area. The break-up of the
investment is given in Table-4.10.
TABLE-4.10
COST PROVISION FOR ENVIRONMENTAL MEASURES
Sr. No.
Description of item Capital Cost
(INR in Crores)
Recurring Cost (Rs in
Crores/annum)
1 Raw water treatment systems 120 5.0
2 Wastewater treatment systems 30 4.0
3 Rainwater harvesting systems 20 0.5
4 Air pollution control systems including ESP
80 8.0
5 Stack (220 m height) 90 6.0
6 Noise pollution control systems 5 0.5
7 Environmental monitoring/ Environmental Laboratory
5 0.5
8 Occupational health & safety 5 0.5
9 Greenbelt development 5 1.0
Total 360 26.0
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4.8 Corporate Social Responsibility
ARS has always believed that managing its business most efficiently and in a cost
effective manner is its primary duty to the society. ARS also believes that it can
contribute to the common cause of the society by bringing in the same level of
corporate efficiency in the administration and management of the various CSR
initiatives.
ARS have provided bore wells in the villages for drinking water. ARS is in
discussion to engage a full time NGO for the social upliftment of the villages by
identifying the necessary programs in consultation with village leaders. Also have
discussed with district administration (District Rural Development Authorities -
DRDA) for implementing SSS (Self Service Scheme – Namakku Name Thittam)
The proposed schemes include
1. Vocational training program;
2. Road laying;
3. Toilet facilities;
4. Drinking water facilities;
5. Cattle for generating livelihood; and
6. Setting up of primary schools.
TABLE – 4.11 (a)
EXPENSES TOWARDS CSR
Sr. No. Description Amount Spent in
INR.
1 Housing aid to the nearby communities 23,54,694/-
2 Upgradation of nearby village school from
8th std to 10th std. 9,73,396/-
3 Drinking water facilities to nearby schools 1,81,501/-
4 Construction of first aid centre with doctor
facilities at Eguvarapalayam village 6,40,315/-
5
Amount spent for construction of
compound water to the local panchayat
school
3,00,000/-
Total 44,49,906/-
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TABLE – 4.11 (b)
EXPENSES TOWARDS CSR
Corporate social responsibility - upto cod - aug'13
Description Actuals (rs) Description Actuals (rs)
School uniform 10,178 Ambulance 463,396
School books 553,600 Diesel & maintenance
School function Water pumps 60,000
Computers 53,808 Bore well 257,274
Printers 30,000 RO. Plant - village 45,000
Toilets Maintenance of RO plant
RO. Plant Public toilets 360,600
Maintenance of RO plant Road 2,500,000
Teacher's salary Sports development 100,000
Medicine 113,500 Hospital 100,000
School sports 25,785 Temple 53,200
School prizes 100,000 Panchayat 19,252
Stationery 63,970 Police station 10,600
Furnitures 600,000 People welfare (saris) 40,000
School maintenance 44,463 EB 2,250
Sieving machines 63,500 School boundary 1,306,000
Drains Water coolers & RO for school 70,000
Development of lab in school 180,300
Total (rs) Rs.16,58,804 Total Rs.55,67,872
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Chapter – 5
Analysis of alternatives (technology and site)
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5.0 ANALYSIS OF ALTERNATIVES (TECHNOLOGY AND SITE)
5.1 Analysis of alternative sites for location of power plant
The proposed site acquired for the additional unit (1 x 350 MW) is adjacent to the
existing plant site of ARS. The adjacent land has been selected based on the
following criteria
Availability of barren land adjacent to existing site
No forest land
No crop land
Nearest village (Siruvapuri) is more than 1 km
Accessibility to railway line
Coal transportation
Absence of ecologically / environmentally sensitive areas within 15 km radius
National highway (NH – 5) is 4.8 km from plant site
Manpower availability from nearby areas
Based on the above criterion, alternate site analysis is not required for the
current expansion activity as the adjacent site is the most viable option for this
project.
5.2 Analysis of Alternative for Unit Size Selection
Unit Size Selection
The most suitable unit size for the proposed boliers for 1 x 135 MW & 1 x 350 MW
has been considered by analysing various major aspects as enumerated below:
i) Provenness based on the quality of main fuel to be fired;
ii) Reliability and availability;
iii) Capacity of the grid for evacuation of power;
iii) Capital expenditure and economics of power generation;
iv) Space requirement;
iv) Manpower requirement.
Provenness
The TG units and matching Coal fired boilers of both the sizes (135 MW and 350
MW) are well tested in India as well as abroad. Both 1x135 MW and 1 x 350MW
are comparable in this aspect.
Reliability and availability
Reliability of 135 MW and 350 MW steam generator and turbo generator are
comparable.
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Dependence on the grid
The dependence on grid for drawal of power, with 1 x 135 & 1 x 350 MW will be
higher when compared to four or more unit configurations.
Space requirement
The space requirement will be marginally less for 1 x 350 MW power station as
compared to the space required for more unit configurations.
Manpower requirement
The manpower requirement with four units station will be around 20% higher
compared to two unit station. This is due to the fact that in 4 unit configuration,
number of plant and equipment will increase.
Capital expenditure and economics of power generation
The capital expenditure of 4 unit station will be around 7-10% higher compared
to 2 unit station. The generation cost also will be higher for 4 – unit configuration
power plant due to higher capital cost, marginally higher heat rate and more
expenditure towards O&M.
Analysis
From the foregoing it could be seen that both the unit sizes have their own
advantages and disadvantages. It is true that capital expenditure and cost of
power generation both will be less in case of 1 x 135 MW & 1 x 350 MW power
plants.
Recommendation on selection of unit size
From the foregoing, it could be seen that for the 2 - unit configuration capital cost
and cost of power generation both will be less as compared to 4 - unit
configuration. However, with 2 – unit configuration, during planned / forced
outage loss of one unit generation will lead less power sale resulting in reduced
revenue during the unit shutdown period.
Selection of 1 x 135 & 1 X 350 MW unit configuration is recommended.
Conclusion and Recommendation:
Overall Recommendation Based on the foregoing it is recommended to go in for 1
x 135 & 1 X 350 MW configuration power plant based on PF boilers.
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Chapter – 6
Environmental monitoring program
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6.0 ENVIRONMENTAL MONITORING PROGRAM
6.1 Introduction
Regular monitoring of environmental parameters is of immense importance to
assess the status of environment during project its operation phase. With the
knowledge of baseline conditions, the monitoring programme will serve as an
indicator for any deterioration in environmental conditions due to operation of the
project, to enable taking up suitable mitigatory steps in time to safeguard the
environment. Monitoring is as important as that of control of pollution since the
efficiency of control measures can only be determined by monitoring.
Usually, as in the case of the study, an impact assessment study is carried over
short period of time and the data cannot bring out all variations induced by the
natural or human activities. Therefore, regular monitoring programme of the
environmental parameters is essential to take into account the changes in the
environmental quality.
6.2 Implementation Schedule of EMP
The mitigation measures suggested in the Chapter-4 will be implemented so as to
reduce the impact on environment due to the operations of the plant operation. In
order to facilitate easy implementation, mitigation measures are phased as per the
priority implementation. The priority of the implementation schedule is given in
Table-6.1.
TABLE-6.1
EMP IMPLEMENTATION SCHEDULE
Sr. No. Recommendations Requirement
1 Air pollution control measures Before commissioning
2 Water pollution control measures Before commissioning
3 Noise control measures Along with the commissioning of the
Project
4 Solid waste management During commissioning of the project
5 Green belt development Stage-wise implementation
6.3 Environmental Monitoring and Reporting Procedure
Regular monitoring shall check whether the commitments proposed are being
met. This may take the form of direct measurement and recording of quantitative
information, such as amounts and concentrations of discharges, emissions and
wastes, for measurement against corporate or statutory standards, consent limits
or targets. It may also require measurement of ambient environmental quality in
the vicinity of a site using ecological/biological, physical and chemical indicators.
Monitoring may include socio-economic interaction, through local liaison activities
or even assessment of complaints.
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Environmental monitoring program
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6.3.1 Objectives of Monitoring
The objectives of environmental post-project monitoring are to:
Verify effectiveness of planning decisions;
Measure effectiveness of operational procedures;
Confirm statutory and corporate compliance; and
Identify unexpected changes.
6.4 Monitoring Schedule
Environmental monitoring schedules are prepared covering various phases of
project advancement, such as erection phase and regular operational phase.
6.4.1 Monitoring Schedule during constructional phase
The proposed expansion envisage setting up of boilers, turbines and establishment
of storage facilities for coal and ash. The construction activities require preparing
land, mobilisation of construction material and equipment to plant site.
The generic environmental measures that need to be undertaken during project
construction stage are given in Table-6.2.
TABLE-6.2
ENVIRONMENTAL MONITORING DURING PROJECT CONSTRUCTION STAGE
Sr. No.
Potential Impact
Action to be Followed Parameters for
Monitoring Frequency of Monitoring
1 Air Emissions All equipment to be operated within specified design parameters
Random checks of equipment logs/ manuals
Periodic
Vehicle trips to be minimized to the extent possible
Vehicle logs Periodic during site clearance & construction activities
Maintenance of DG set emissions to meet stipulated standards
Gaseous emissions (SO2, HC, CO, NOx)
Periodic emission monitoring
Ambient air quality within the premises of the plant area to be monitored
The ambient air quality will conform to the standards for PM10, PM2.5, SO2, NOx, and CO
As per CPCB / SPCB requirement or on monthly basis whichever is earlier
2 Noise List of all noise generating machinery onsite along with age to be prepared Equipment to be maintained in good working order
Equipment logs, noise reading
Regular during construction activities
Night working is to be
minimized.
Working hour
records
Daily records
Generation of vehicular noise
Maintenance of records of vehicles
Daily records
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Sr. No.
Potential Impact
Action to be Followed Parameters for
Monitoring Frequency of Monitoring
Noise to be monitored in ambient air within the plant premises
Spot Noise recording As per CPCB/SPCB requirement or on quarterly basis whichever is earlier
3 Wastewater Discharge
No untreated discharge to be made to surface water, groundwater or soil
No discharge hoses shall be in vicinity of watercourses
Periodic during construction activities
4 Soil Erosion Protect topsoil stockpile where possible at edge of site
Effective cover in place
Periodic during construction activities
5 Drainage and
effluent Management
Ensure drainage system
and specific design measures are working effectively The design to incorporate existing drainage pattern and avoid disturbing the same
Visual inspection of
drainage and records thereof
Periodic during
construction activities
6 Waste Management
Implement waste management plan that
identifies and characterizes every waste arising associated with proposed activities and which identifies the procedures for collection, handling & disposal of each waste arising.
Comprehensive Waste Management
Plan should be in place and available for inspection on-site Compliance with MSW Rules, 1998 and Hazardous Wastes (Management and Handling Rules), 2003
Periodic check during
construction activities
7 Non-routine events and accidental releases
Plan to be drawn up, considering likely emergencies and steps required to prevent/limit consequences
Mock drills and records of the same
Periodic during construction activities
8 Health Employees and migrant labour health check ups
All relevant parameters including
HIV
Regular check ups
9 Environmental Management Cell/ Unit
The Environmental Management Cell/Unit is to be set up to ensure implementation and monitoring of environmental safeguards
Responsibilities and roles will be decided before the commencement of work
During construction phase
10 Loss of flora
and fauna
Re-vegetation as per Forest
guidelines
No. of plants,
species
During site
clearance
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6.4.2 Monitoring Schedule during Operational Phase
During operational stage, continuous air emissions from power boilers,
wastewater disposal to river, non-hazardous waste such as ash, hazardous used
oily wastes are expected.
The following attributes which merit regular monitoring based on the
environmental setting and nature of project activities are listed below:
Source emissions and ambient air quality;
Groundwater levels and ground water quality;
Water and wastewater quality (water quality, effluent & sewage quality etc);
Solid and hazardous waste characterisation (fly ash, bottom ash, oily wastes,
ETP sludge, used and waste oil);
Soil quality;
Noise levels (equipment and machinery noise levels, occupational exposures
and ambient noise levels); and
Ecological preservation and afforestation.
The following routine monitoring programme as detailed in Table-6.3 shall be
implemented at site. Besides to this monitoring, the compliances to all
environmental clearance conditions and regular permits from SPCB/MoEF shall be
monitored and reported periodically (once every six months).
TABLE-6.3
ENVIRONMENTAL MONITORING DURING OPERATIONAL PHASE
Sr. No.
Potential Impact
Action to be Followed Parameters for
Monitoring Frequency of Monitoring
1 Air Emissions Stack emissions from power boilers to be
optimized and monitored
Gaseous emissions (PM10, PM2.5, PM
size distribution, SO2, CO, NOx)
Continuous monitoring using
on-line equipment during entire operation phase
Stack emissions from DG set to be optimized and monitored
Gaseous emissions (SO2, HC, CO, NOx)
Periodic during entire operation phase
Ambient air quality within the premises of the plant and nearby habitations to be monitored Exhaust from vehicles to be minimized by use of fuel efficient vehicles and well maintained vehicles having PUC certificate
PM10, PM2.5, SO2, NOx, O3, CO, Lb, As, Ni, C6H6, B(a)P, NH3 and Hg Vehicle logs to be maintained
As per CPCB/ SPCB requirement or on weakly basis whichever is earlier
Measuring onsite data of Meteorology
Wind speed, direction, temp., relative humidity and rainfall, solar radiation
Continuous monitoring using on-line weather station during operation phase
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Sr. No.
Potential Impact
Action to be Followed Parameters for
Monitoring Frequency of Monitoring
2 Noise Noise generated from operation of power boilers to be optimized and monitored Noise generated from operation of DG set to be optimized and monitored
and should be provided with acoustic enclosures
Spot Noise Level recording; Leq (night), Leq (day), Leq (dn) Noise levels to be recorded at 1m distance from the
respective unit
Once every six months
Generation of vehicular noise
Maintain records of vehicles
Periodic during operation phase
3 Wastewater Discharge
Wastewater (treated and untreated) analysis
As per CPCB Once in a month
4 Drainage and effluent Management
Ensure drainage system and specific design measures are effective & working Design to incorporate existing drainage pattern and avoid disturbing the same
Visual inspection of and cleaning of drainage before monsoon season
Periodic during operation phase
5 Water Quality and Water Levels
Monitoring of groundwater quality around ash pond and ground water levels
Comprehensive monitoring as per IS: 10500 Groundwater level in meters bgl
Once in a month Water level maintaining once every season
River water quality downstream to discharge
As per IS: 10500 (2012)
Once in a month
6 Emergency preparedness, such as fire fighting
Fire protection and safety measures to take care of fire and explosion hazards, to be assessed and steps taken for their prevention
Mock drill records, on site emergency plan, evacuation plan
Periodic during operation phase
7 Maintenance of
flora and fauna
Vegetation, greenbelt /
green cover development
No. of plants,
species
Once in summer
and winter
8 Waste Management
Implement waste management plan that identifies and characterizes every waste arising associated with the plant activities and which identifies the procedures for collection, handling & disposal of each waste
arising
Records of solid waste generation, treatment and disposal
Periodic during operation phase
9 Soil quality Maintenance of good soil quality
Physico-chemical parameters and metals.
Periodical monitoring at ash dyke
10 Health Employees and migrant labour health check ups
All relevant parameters
Regular check-ups
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6.5 Monitoring Methods and Data Analysis of Environmental Monitoring
All environmental monitoring and relevant operational data will be stored in a
relational database and should be able to link to GIS system. This will enable
efficient retrieval and storage and interpretation of the data. Regular data
extracts and interpretive reports will be sent to the regulator.
6.5.1 Air Quality Monitoring and Data Analysis
6.5.1.1 Stack Monitoring
The emissions from all the stacks shall be monitored regularly. The exit gas
temperature, velocity and pollutant concentrations shall be measured. Any
unacceptable deviation from the design values shall be thoroughly examined and
appropriate action shall be taken. Air blowers shall be checked for any drop in exit
gas velocity.
6.5.1.2 Workspace Monitoring
The concentration of airborne pollutants in the workspace/work zone environment
shall be monitored periodically. If concentrations higher than threshold limit values
are observed, the source of fugitive emissions shall be identified and necessary
measures shall be taken. Methane and non-methane hydrocarbons shall be
monitored in oil storage area once in a season. If the levels are high, suitable
measures as detailed in EMP shall be initiated.
6.5.1.3 Ambient Air Quality Monitoring
The ground level concentrations of PM10, PM2.5, SO2 and NOX in the ambient air
shall be monitored at regular intervals. Any abnormal rise shall be investigated to
identify the causes and appropriate action shall be initiated. Greenbelt shall be
developed for minimising dust propagation. The ambient air quality data should be
transferred and processed in a centralised computer facility equipped with required
software. Trend and statistical analysis should be done.
6.5.2 Water and Wastewater Quality Monitoring and Data Analysis
To ensure a strict control over the water consumption, flow meters shall be
installed for all major inlets. All leakages and excess shall be identified and
rectified. In addition, periodic water audits shall be conducted to explore further
possibilities for water conservation.
Methods prescribed in "Standard Methods for Examination of Water and
Wastewater" prepared and published jointly by American Public Health
Association (APHA), American Water Works Association (AWWA) is recommended.
6.5.2.1 Monitoring of Wastewater Streams
All the wastewater streams in the project area shall be regularly analysed for flow
rate, physical and chemical characteristics.
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Such analysis is carried out for wastewater at the source of generation, at the point
of entry into the wastewater treatment plant and at the point of final discharge.
These data shall be properly documented and compared against the design values
for any necessary corrective action. 6.5.2.2 Monitoring of Groundwater
The monitoring of groundwater is the most important tool to test the efficiency of
ash pond performance. This is indispensable as it provides detection of the
presence of waste constituents in groundwater in case of leachate migration. In
this programme, water samples are taken at a predetermined interval and analysed
for specific pollutant expected to be in the leachate. For early detection of leachate
migration, if any, it is suggested to construct piezometers around the ash dyke.
In addition to piezometers, monitoring wells should be installed to a depth of at
least 3-m below the maximum historic groundwater depth. Based on assumptions
and data about the characteristics of leachate to be generated, approximate
permeability of soils in the zone of aeration and direction and velocities of
groundwater flow, the maximum probable aerial extent of contaminant migration
can be estimated as a basis for establishing the position of monitoring wells.
A minimum of two ground monitoring wells should be typically installed at ash
disposal facility: one up-gradient well and one down-gradient well. It is suggested
to collect water samples and analyse. Records of analysis should be maintained.
6.5.3 Noise Levels
Noise levels in the work zone environment such as boiler house, cooling tower
area, DG house shall be monitored. The frequency shall be once in three months in
the work zone. Similarly, ambient noise levels near habitations shall also be
monitored once in three months. Audiometric tests should be conducted
periodically for the employees working close to the high noise sources.
6.6 Reporting Schedules of the Monitoring Data
It is proposed that voluntary reporting of environmental performance with
reference to the EMP should be undertaken.
The environmental monitoring cell shall co-ordinate all monitoring programmes at
site and data thus generated shall be regularly furnished to the state/central
regulatory authorities.
The frequency of reporting shall be on once every six months to the local state PCB
officials and to Regional office of MoEF. The Environmental Audit reports shall be
prepared for the entire year of operations and shall be regularly submitted to
regulatory authorities.
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6.7 Infrastructure for Monitoring of Environmental Protection Measures
A well-equipped laboratory with consumable items shall be provided for monitoring
of environmental parameters in the site. Alternatively, monitoring can be
outsourced to a recognized accredited laboratory.
The following equipment and consumables shall be made available in the site for
environmental monitoring or alternatively the monitoring can be outsourced to a
recognized accredited laboratory.
Air quality and meteorology
High volume samplers, stack monitoring kit, personal dust sampler, central
weather monitoring station, spectrophotometer (visible range), single pan
balance, flame photometer, relevant chemicals as per IS:5182.
Water and wastewater quality
The sampling shall be done as per the standard procedures laid down by IS:2488.
The equipments and consumables required are:
BOD incubator, COD reflex set-up, refrigerator, oven, stop watch, thermometer,
pH meter, distilled water plant, pipette box, titration set, dissolved oxygen
analyser and essential chemicals.
Noise levels
Noise monitoring shall be done utilising an integrating sound level meter to record
noise levels in different scales like A-weighting with slow and fast response options.
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Project benefits
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8.0 PROJECT BENEFITS
8.1 Introduction
Proposed expansion of the power plant will result in a considerable growth in
industrial and commercial sector in the state. Small and medium scale industries
may be further developed as a consequence.
Proposed expansion would be beneficial in reducing the existing and ever
escalating demand of electricity in the southern part of the country.
In operation phase, the plant would require significant workforce of non-technical
and technical persons. Migration of persons with better education and
professional experience will result in increase of population and literacy in the
surrounding villages.
8.1.1 Availability of Quality Power
The plant would be generating about 545 MW of power after the current
expansion and this project is inline with the central government’s massive power
capacity addition plan, which sets a target of adding 88,537 MW of power
generation capacity in the country in the 12th plan (2012-2017) as per the report
of Integrated Resource Planning Division, Planning wing, CEA.
8.1.2 Improvements in the Physical Infrastructure
The beneficial impact of the power plant on the civic amenities will be substantial
after the commencement of project activities. The basic requirement of the
community needs will be strengthened by extending healthcare, educational
facilities to the community, building/strengthening of existing roads in the area.
ARS will initiate the above amenities either by providing or by improving the
facilities in the area, which will help in uplifting the living standards of local
communities.
8.1.3 Improvement in the Social Infrastructure
Generation of employment: The project will create direct and indirect
employment opportunities;
Increase in purchasing power and improved standard of living of the area;
Further development of small and medium scale industries may be developed
as consequence;
Increased revenue to the state by way of royalty, taxes and duties;
Overall growth of the neighboring area viz.:
Health and family welfare;
Watershed development;
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Sustainable livelihood and strengthening of village Self Help Groups; and
Infrastructure development.
In addition to above, due to increase in purchasing power of local habitants:
There shall be significant change in the socio-economic scenario of the area;
The proposed expansion shall enhance the prospects of employment;
Recruitment for the unskilled and semiskilled workers for the proposed project
will be from the nearby villages;
The basic amenities viz. roads, transportation, electricity, proper sanitation,
educational institutions, medical facilities, entertainment, etc., will be
developed as far as possible; and
Overall the project will change living standards of the people and improve the
socio-economic conditions of the area.
8.1.4 Employment Potential
The impact of the project on the economic aspects can be clearly observed. The
project activities will provide employment to persons of different skills and trades.
The local population will be given preference to employment. The employment
potential will ameliorate economic conditions of these families directly and
provide employment to many other families indirectly who are involved in
business and service oriented activities.
The employment of local people in primary and secondary sectors of project shall
upgrade the prosperity of the region. This in-turn will improve the socio-economic
conditions of the area.
During construction phase of the project, this project will provide temporary
employment to many unskilled and semi-skilled laborers in nearby villages.
This project will also help in generation of indirect employment to those
people who render their services for the personnel directly working in the
project; and
During operational phase, considerable number of people will be benefited by
provision of services. Thus, the direct and indirect employment generation by
this plant expansion.
The trend of out migration for employment, if any, is likely to be reduced due to
better economic opportunities available in the area.
During the erection phase, about 50 people on average will be employed. The
additional manpower of power plant during operational period is estimated to be
about 200 persons.
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9.0 ADMINISTRATIVE ASPECTS
9.1 Institutional Arrangements for Environment Protection and Conservation
Environment Management cell is being headed by a senior manager and will
constitute environmental engineer, scientists, chemists and supervisors. The
Organizational Structure of Environment Management is presented in Figure-9.1.
The Manager (Env) will be responsible for Environment management activities.
Basically, this department will supervise the monitoring of environmental
pollution levels viz. source emission monitoring, ambient air quality, water and
effluent quality, noise level either departmentally or by appointing external
agencies wherever necessary.
In case the monitored results of environmental pollution found to exceed the
allowable limits, the Environmental Management Cell will suggest remedial action
and get these suggestions implemented through the concerned authorities.
The Environmental Management Cell also co-ordinates all the related activities
such as collection of statistics of health of workers and population of the region,
afforestation and greenbelt development.
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Administrative aspects
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GENERAL MANAGER
(O & M)
DY. GENERAL MANAGER
(O & M)
MANAGER
(ENVIRONMENT)
SAFETY OFFICERENVIRONMENT
ENGINEER
ECOLOGIST/
HORTICULTURIST
CHEMISTS SUPPORT STAFF
FIGURE-9.1
ORGANIZATIONAL STRUCTURE OF ENVIRONMENT MANAGEMENT
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10.0 SUMMARY AND CONCLUSION
10.1 Identification of project and project proponent
ARS, a pioneer in the field of manufacturing TMT re-bars and Mild Steel Billets
intends an expansion & augmentation of its existing coal based thermal power
plant at Sithurnatham, Sirupuzhalpettai & Eguvarapalayam villages,
Gummidipoondi village, Thiruvallur district, Tamil Nadu. The cost of the total
project is about INR. 2400 crores, which includes INR. 360 Crores for
environmental protection measures.
10.1.1 Environmental setting of the site
The study area map of 10 km radius around the plant site is given in Figure-10.1.
The environmental setting of the plant site is given as follows:
TABLE – 10.1
ENVIRONMENTAL SETTING OF THE PLANT
Sr. No. Particulars Details
1 Site-coordinates Refer Figure-1.3 (Chapter 1)
2 Elevation 18.0 m AMSL
4 Climatic conditions (Plant site) 1st May to 31st July 2014 a. Max. Temp: 43.04 0C b. Min. Temp: 22.0 0C c. Rainfall: 275.6 mm
5 Land use Industrial
6 Nearest highway NH-5 – 4.8 km, East
7 Nearest railway station Gummidipoondi R.S. – 6.1 km, ESE
8 Nearest airport Anna International Airport, Chennai – 48.3km,
SSE
9 Nearest habitations Chitoornatham – 0.5 km, West Eguvarpalayam – 1.7 km, NNW
10 Densely populated area Chennai city – 44.7 km, SSE
11 Inland water bodies Chittoornatham pond – 1.0 km, West Pulicat lake – 8.1 km, NE Arani river – 7.4 km, SSE Pallavada lake – 6.6 km, NW
12 Ecologically sensitive zones like
Wild Life Sanctuaries, National Parks and biospheres
Nil
13 Defense establishments None within 10 km radius
14 Socio-economic factors No Resettlement and Rehabilitation issues
15 Seismicity zone Zone – III as per IS: 1893 (Part-1) 2002
16 Nearest sea coast Bay of Bengal –26.7 km, East
17 Reserve forests Puliyur forest – 3.1 km, SSW Periyapuliyur forest – 4.3 km, SW
Pallavakam R.F. – 5.6 km WSW Thervoy R.F. – 5.7 km, SW Manali R.F. – 5.7 km, SSW Siruvada forest – 8.2 km, WSW Palem forest – 12.3 km, WNW
18 Historical / archaeological
places
Nil within 15.0 km from project boundary
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FIGURE-10.1
10 KM RADIUS STUDY AREA OF THE PROJECT SITE
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10.2 Details of the proposed project
The proposed expansion will be operated on coal as main fuel to generate 545 MW
of power. The details of the project are given in Table-10.2.
TABLE-10.2
SALIENT FEATURES OF THE PROPOSED PROJECT
Sr. No. Features Description
1 Total capacity 545 MW
2 Configuration Under operation: 1 x 60 MW Proposed: 1 x 135 MW + 1 X 350 MW
3 Technology 1 X 60 MW & 1 X 135 MW PF Boiler with re-heat cycle: M.S: 170 kg/cm2
/ 537OC;
Reheat: 537OC
1 X 350 MW – Super Critical
PF Boiler with re-heat cycle: M.S: 255 kg/cm2
/ 585OC; Reheat: 585OC
4 Boilers 1 x 235.13 TPH; Sub critical (Existing 1 x 60 MW) 1 x 563 TPH; Sub critical (Proposed 135 MW) 1 x 950 TPH; Super critical (Proposed 350 MW) CFBC/Pulverized Coal fired, natural circulation boilers
5 Generators Three generators with rated 60 MW, 11KV, 50 Hz, 3 ph and 0.8 PF, 135 MW & 350 MW
6 Power evacuation Power evacuation will be from Thervaikandigai, which is located 14.0 km from site
7 Condenser Air cooled condenser
8 Auxiliary Cooling
System
Finfan coolers for cooling of turbine, generator and
boiler auxiliaries
9 HFO/LDO Storage
Tanks
2 x 300 KL HFO tanks and 2 x 150 KL LDO tanks
10 Switchyard, Generator, Transformer and Station Transformer
230 KV System
11 Fuel Coal
12 Source of Coal Indonesia Coal (Imported)
13 Coal Handling Ground hoppers, stacker, reclaimers and double stream conveying system
14 Coal Requirement 2.31 MTPA at 85% PLF
15 Sulphur content 0.5%
16 Ash Content in Coal 9.0%
17 A B
Ash generation Bottom Ash Fly Ash
0.135 MTPA 0.108 MTPA 0.027 MTPA
18 Ash Handling Dry ash collection
19 ESP efficiency 99.99%
20 Stack 145 m AGL [Common for 1 x 60 MW & 1 X 135 MW] 220 m AGL [Common for 1 x 350 MW]
21 Total water demand 240 KLD (0.098 cusec)
22 Source of water Existing borewells
23 Project cost INR. 2400 Crores
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10.2.1 Technology and process description
The existing 60 MW and the proposed 135 MW power plant will be a conventional
thermal power plant operating on sub critical pressure, single reheat steam cycle
with regenerative feed heating arrangement. The primary fuel to be used for the
power generation will be coal. The mode of transportation of coal will be by road
from Ennore port. The superheated steam from the boilers at 170 bar and 537ºC
is supplied to the High Pressure (HP) turbine. This steam, after expansion in the
HP turbine is sent back to the boiler as cold reheat steam. After reheating in the
boiler, the reheated steam (Hot reheat steam) at about 42 bar and 537 ºC is sent
to Intermediate Pressure (IP) and Low Pressure (LP) turbine and is finally
exhausted into the condenser. The exhaust steam is cooled and condensed in an
air cooled condenser. The proposed 1 X 350 MW will be operated on Super critical
pressure PF Boiler with re-heat cycle: M.S: 255 kg/cm2/ 585OC; Reheat: 585OC
10.2.2 Power evacuation
Power evacuation will be from Thervaikandigai, which is located 14.0 km from
site.
10.2.3 Land requirement
The existing plant operates in an area of 25.49 ha (62.99 acres). Additionally
11.49 ha (28.39 acres) of barren land has been acquired for the current
expansion activities. Totally the plant after expansion operates in an area of
36.98 ha (91.38 acres).
10.2.4 Fuel Requirement
The primary fuel of the power plant will be 100% Indonesian coal. The maximum
total annual coal consumption for the power plant after expansion will be about
2.31 MTPA. Coal from Indonesia would be transported through sea to Ennore port
and thereon through trucks to the existing plant site.
10.2.5 Water Requirement
The total water demand for the plant after expansion will be about 240 KLD,
which will be met from existing borewells and rain water harvesting.
10.2.6 Manpower
The total manpower of the existing plant is about 150 employees. Upon
expansion, additional 200 employees will be required, which includes officers and
supervisors also.
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10.3 Baseline Environmental Status
The 10 km radial distance from the existing plant boundary has been considered
as study area for Environmental Impact Assessment (EIA) baseline studies.
Environmental monitoring for various attributes like meteorology, ambient air
quality, surface and ground water quality, soil characteristics, noise levels and
flora & fauna have been conducted at specified locations and the secondary data
collected from various Government and Semi-Government organizations. The
baseline environmental monitoring studies were carried out from 1st May 2014 to
31st July 2014.
10.3.1 Land Use
The land use pattern of the study area has been studied by analyzing the available
secondary data published in the District Primary Census abstract of the year 2001.
In addition to the establishment of land use pattern based on the review of
secondary data, the land use pattern in study area and its buffer zones covered
within a radius of 10 km from the existing plant has been established through
interpretation of satellite imageries and by means of preparation of land use/land
cover map.
10.3.2 Meteorology
On-site monitoring was undertaken for various meteorological parameters in
order to generate the site-specific data. Data was collected every hour
continuously from 1st May to 31st July 2014. The maximum and minimum
temperatures recorded at the site during the study period are 43.0oC and 22.00C.
The humidity found varying from 18% to 100%. The predominant winds are
mostly from West (18.5%) followed by South (14.6%). Calm conditions were
recorded for 3.34%.
10.3.3 Ambient Air Quality
To establish the baseline status of the ambient air quality in the study area, the
air quality was monitored at 8 locations. The summary of the Ambient Air Quality
monitored is given in Table-10.3.
TABLE- 10.3
SUMMARY OF AMBIENT AIR QUALITY IN THE STUDY AREA
PM2.5 PM10 SO2 NOx CO 11.0-27.4 33.4-83.1 6.4-26.9 9.3-33.2 141-343
Concentrations are expressed in g/m3
The results of the monitored data indicate that the ambient air quality of the region
in general is in conformity with respect to rural/residential norms of National
Ambient Air Quality standards of CPCB, with present level of activities. Mercury
concentration was observed to be less than 0.001 g/m3.
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10.3.4 Ambient Noise Levels
The noise monitoring has been conducted for determination of ambient noise levels
at ten locations in the study area. The observations are given below:
Day time Noise Levels (Lday)
The day time noise levels were ranged in between 45.2 dB (A) to 68.2 dB (A). The
maximum value 68.2 dB (A) was recorded at was recorded at Melpakkam village
(N2), and the minimum value 45.2 dB (A) was recorded at Gumpuahintala village
(N10). It is observed that the day time noise levels are in accordance to the
prescribed limit of 55 dB (A) for Residential areas.
Night time Noise Levels (Lnight)
The night time noise levels were ranged in between 40.8 dB (A) to 53.9 dB (A).
The maximum value 53.9 dB (A) was recorded at Melpakkam village (N2), and the
minimum value 40.8 dB (A) was recorded at Gumpuahintala village (N10). It has
been found that the night time noise levels are in accordance with prescribed limit
of 45 dB (A) for Residential areas.
10.3.5 Water Quality
Six ground water samples and two surface water samples within the study area
were considered for assessment.
Surface Water Quality
The analysis results indicate that the pH value at SW1 & SW2 was found to exist as
8.1 & 7.1 respectively, which is well within the specified standard of 6.5 to 8.5.
The Total Dissolved Solids (TDS) concentration was found as 652 & 745. The
chlorides were found as 105.5 - 211 mg/l. The Sulphates were found as 28.7 -
38.1 mg/l. Heavy metals in very low concentration and are well within the
prescribed limits. It is evident from the above values that all the parameters are
found to comply with the requirements of IS: 10500 (2012) "Specifications for
Drinking Water."
Ground Water Quality
The analysis results indicate that the pH ranges in between 7.4 to 7.8, which is
well within the specified standard of 6.5 to 8.5. The maximum pH of 7.8 was
observed at GW3 and the minimum pH of 7.4 was observed at GW5. Total
hardness was observed to be ranging from 190 to 350 mg/l. The maximum
hardness (350 mg/l) was recorded at GW2 and the minimum (190 mg/l) was
recorded at GW6. Chlorides were found to be in the range of 24.8-53.2 mg/l, the
maximum concentration of chlorides (53.2 mg/l) was observed at GW3 & GW6,
and where as the minimum value (24.8 mg/l) was observed at GW1. Nitrates were
found to be in the range of 3.9 – 37.3 mg/l. The maximum value observed at GW3
(37.3 mg/l) whereas the minimum value observed at GW1 (3.9 mg/l).
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The Total Dissolved Solids (TDS) concentrations were found to be ranging in
between 223 to 414 mg/l, the maximum TDS observed at GW6 (414 mg/l) and
minimum concentration of TDS observed at GW1 (223 mg/l). Potassium is found in
between 1.3 to 8.5 mg/l. It is evident from the above values that all the
parameters are found to comply with the requirements of IS: 10500 (2012)
"Specifications for Drinking Water."
10.3.6 Soil Quality
A total of eight samples within 10 km radius of the plant site were collected for the
assessment of soil quality. The sampling was carried out during study period. It
has been observed that the pH of the soil in the study area ranged from 7.4 to
7.9 the maximum pH value of 7.9 was observed at S3, where as the minimum
value of 7.4 was observed at S4 and S8. The pH of the soil is slightly alkaline to
moderately alkaline. The electrical conductivity was observed to be in the range
of 143 µmhos/cm to 210 µmhos/cm, with the maximum observed at S7 with the
minimum observed at S4 respectively. The nitrogen values range between 71.4-
121.9kg/ha. The nitrogen content in the study area falls in less to good category.
The phosphorus values range between 61.6 to 94.4 kg/ha, indicating that the
phosphorus content in the study area falls in average sufficient to more than
sufficient category. The potassium values range between 244.9 – 482.4 kg/ha.
The potassium content in the study area falls in average to more than sufficient
category.
10.3.7 Flora and Fauna
As per MoEF and Forest Department of Tamilnadu state, it reveals that there are
no Wildlife sanctuaries, National parks/biosphere reserves in 10 km radius from
the proposed site boundary. As per the records of the Botanical Survey of India
there are no plants of conservation importance in the study area. It can be
concluded that there is one species belonging to Sch-I,2 species belongs to Sch-II
and rest of species belongs Sch-III, Sch-IV and Sch-V of Wildlife Protection Act,
1972.
10.3.8 Socio-Economic Environment
As per 2001 census the study area consists of 2,78,458 persons inhabited in the
study area of 10 km radial distance from the periphery of the proposed plant. The
males and females constitute 50.86 % and 49.14 % of the study area population
respectively. The average household size of the study area is 4.33 persons. In the
study area, 21.45% of the population belongs to Scheduled Castes (SC). The
study area experiences average literacy rate of 63.73%. As per 2001 census
records, altogether the main workers works out to be 30.71% of the total
population. The marginal workers and non-workers constitute to 8.19% and
61.11% of the total population respectively.
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10.4 Anticipated Environmental Impacts
The environmental impacts during construction and operation phases of the
project have been assessed and adequate management plan has been evolved to
mitigate the impacts.
10.4.1 Impacts during Constructional Phase
The environmental impacts during the erection stage will be short term,
temporary in nature and will be confined very close to the project site. The
manpower required for these activities should preferably be deployed from
nearby villages.
Land Environment
There is no forest land or ecological sensitive land within proposed additional
plant site. Hence, no major loss of agricultural productivity is envisaged.
Impact on Soil
The construction activities will result in loss of some vegetation cover, topsoil and
earthen material to some extent in the plant area. However, it is proposed to use
the soil and earthen material for greenbelt development and levelling of project site.
Greenbelt will be developed in phased manner from construction stage onwards in
the peripheral boundary of the additional project site.
Apart from localized construction impacts at the plant site, no adverse impacts on
soil in the surrounding area are anticipated.
Impact on Air Quality
The sources of emission during the construction period are from the movement of
equipment at site and dust emitted during the levelling, grading, earthwork,
foundation works. Exhaust emissions from vehicles and equipment deployed during
the construction phase are also likely to result in marginal variation in the levels of
SO2, NOx, PM and CO. The impact will be for short duration and confined to the
project boundary and the same is expected to be negligible outside the plant
boundaries. The impact will, however, be reversible, marginal and temporary in
nature. Proper maintenance of vehicles and construction equipment will help in
controlling the gaseous emissions. Water sprinkling on roads and construction site
will prevent the fugitive dust.
Impact on Terrestrial Ecology
The initial construction works at the project site involves land clearance. Greenbelt
will be developed phase wise during construction to improve the aesthetic value in
the area and to screen out the fugitive dust generated during construction.
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The removal of vegetation from the soil and loosening of the topsoil generally
causes soil erosion. However, such impacts will be confined to the project site and
will be minimized through paving and water sprinkling.
There are no existing matured wooded and useful trees in the site. However,
greenbelt will be developed surrounding the plant facilities. Thus, no major adverse
impacts are envisaged on terrestrial ecology.
Socio-Economic Impacts
Services of skilled and unskilled workers of different trades are required in large
numbers. The project will provide either direct or indirect job opportunities to the
local population as far as possible. These earnings are likely to change the economic
status of local people.
10.4.2 Impacts during Operational Phase
Impact on Soil
Most of the impacts of power plant project on soils are restricted to the construction
phase, which will get stabilized during operational phase. The impact on the topsoil
will be confined to the proposed main plant area as all the activities are limited in
the project site boundary only.
Impact on Air Environment
The impact on air quality is assessed based on emissions of the plant. Particulate
Matter (PM), Sulphur dioxide (SO2) and Oxides of Nitrogen (NOx) will be the
important pollutants emitting from the power plant. The maximum resultant
ground level concentrations of PM, SO2 and NOx are given in Table-10.4.
TABLE-10.4
RESULTANT CONCENTRATIONS DUE TO INCREMENTAL GLCs
Pollutant Concentration ( g/m3)
Standards Baseline Incremental Resultant
PM 83.1 1.39 84.49 100
SO2 26.9 22.14 49.04 80
NOx 33.2 15.66 48.86 80
A perusal of previous sub-section reveal that the maximum incremental short-term
24 hourly ground level concentrations for PM, SO2 and NOx likely to be encountered
in the operation of the power project are 1.39, 22.14 and 15.66 g/m3 respectively
occurring at a distance of about 2.0 km in the East direction.
Impact on Water Environment
ARS has already received uptake letter for 800 m3/day water from existing
borewell vide letter no. 21-4 (192)/CGWA/SECR/2010-1839 dt. 16 March 2010.
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Garland drains around the ash dyke will be provided for the collection of run-off
water during monsoon season. The wastewater generated, will be treated and
mixed in guard pond and finally utilised for ash handling system and green belt
development.
The guard pond will be suitably lined to prevent percolation into ground. The ash
pond will be provided with HDPE lining to prevent any kind of percolation into
ground. Therefore the impact on surface and ground water will be insignificant.
Impact of Solid Waste Generation
Imported coal (100%) will be used in the existing & the proposed power project.
The details of the solid waste generation are given in Table- 10.5.
TABLE- 10.5
EXPECTED SOLID WASTE FROM POWER PLANT
Sr. No. Plant Quantity of Generation Mode of Disposal
1 Ash* Fly ash Bottom ash
0.135 MTPA 0.108 MTPA 0.027 MTPA
Emphasis will be given for supply to potential users in dry from. Remaining ash will be disposed into HDPE lined ash dyke through HCSD method
2 Used Oil 2000 KLPA Will be supplied to authorized recyclers
3 Sewage sludge 2.4 TPA Sent to sludge drying beds and used as manure
4 Domestic solid waste / municipal solid waste
5.25 TPA Organic portion will be dried, composted and used as manure. Inorganic portion will be handed to
authorised recyclers
Major portion of the ash will be utilized by supplying to potential users. Efforts
will be made to utilize 100% fly ash as per the Fly Ash Notification, 1999 and as
amended later.
It is proposed to collect fly ash from ESP hoppers in dry form and provide/supply
to potential ash users depending on the demand. The balance unutilized ash will
be disposed off using High Concentrated Slurry Disposal (HCSD) technology.
Impact on Aquatic Ecology
The impacts on aquatic ecology due to project would be negligible as the treated
effluents from the power project will meet the prescribed standards prior to final
discharge. Similarly, as the discharge water will not have much higher
temperature than the receiving body, no thermal effects on receiving body due to
discharge are envisaged. Hence, the impacts on ecology of the region will be
insignificant.
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Impact on Reserve/Protected Forest
The incremental gaseous concentrations and noise generated during operation of
the power plant are not likely to cause any adverse impact on ecology of forest
bocks within the study area.
Impacts of Noise Levels
The noise generating sources are pumps, compressors and boilers. The predicted
noise levels will be ranging in between 32 to 36 dB(A) and the same will recede
further as the distance increases. Hence, the impact of the noise levels on the
surroundings will be insignificant.
Impact on Human Health
The impact from the air emissions is not expected to be significant since the stack
design and the atmospheric conditions are such that the ambient air quality at
present as well as in future after the proposed facility will be within the
prescribed ambient air quality limits set forth by CPCB.
Impact on Public Health and Safety
The discharge of waste materials (stack emission, wastewater and solid wastes)
from process operations may have potential impact on public safety and health.
The wastewater generated from power plant will be treated before discharging
outside. It is proposed to reuse the wastewater to the maximum extent. Since,
the adverse impacts on ambient air and soil quality are predicted to be low it is
anticipated that with effective implementation of control measures suggested for
pollution control, the impact on public health will be minimum.
10.5 Environment Management Plan
10.5.1 Environment Management Plan during Construction Phase
Air Quality Management
The activities like site development, grading and vehicular traffic contribute to
increase in PM and NOx concentrations. The mitigation measures recommended to
minimize the impacts are:
Water sprinkling in construction area;
Asphalting the main approach road;
Proper maintenance of vehicles and construction equipment; and
Tree plantation in the area earmarked for greenbelt development.
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Water Quality Management
The mitigation measures recommended to minimize the impacts are sedimentation
tank to retain the solids from run-off water; oil and grease trap at equipment
maintenance centre; Septic tanks to treat sanitary waste at labour camp; and
utilizing the wastewater in greenbelt development. The wastewater from labour
colony will contribute to higher BOD concentrations. The mitigation measures
recommended to minimize the impacts are:
Sedimentation tank to retain the solids from run-off water;
Oil and grease trap at equipment maintenance centre;
Packaged STP/Septic tanks to treat sanitary waste at labour colony; and
Utilizing the wastewater in greenbelt development.
Noise Level Management
Operation of construction equipment and vehicular traffic contribute to the
increased noise level. Recommended mitigation measures are:
Good maintenance of vehicles and construction equipment;
Restriction of construction activities to day time only;
Plantation of trees around the plant boundary to attenuate the noise; and
Provision of earplugs and earmuffs to workers.
Ecological Management
During construction, vegetation in the plant premises is required to be cleared. The
measures required to be undertaken to minimise the impact on the ecology are:
The felling of trees will be kept at minimum; and
The greenbelt having vegetation density of 2500 trees/ha will be developed.
Social community Management
Constructional activities will generate employment to local and near by villages. For
construction work force, temporary sanitation facilities (septic tanks and soak pits)
will be set-up for disposal of sanitary sewage. Similarly, rest rooms and canteen
facilities will be provided for truck drivers during construction as well as operation
phase of power plant.
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10.5.2 Environment Management Plan during Operation Phase
Air Pollution Management
Fugitive and stack emissions from the power plant will contribute to increase in
concentrations of PM, SO2, and NOx pollutants. The mitigative measures
recommended in the plant are:
Installation of ESP of efficiency more than 99.99% to limit the PM concentrations
below 50 mg/Nm3;
Provision of stack of adequate height (Existing – 145.0 m & Proposed – 220 m)
for wider dispersion of gaseous emissions;
Provision of water sprinkling system at raw material storage yard;
Asphalting of the roads within the plant area;
Provision of dust extraction systems at dust generating source.
Developing of Greenbelt around the plant to arrest the fugitive emissions;
Online flue gas monitors as well as flue gas flow rates and temperature
measurement shall be provided for all stacks; and
Usage of washed/beneficiated coal may be explored.
Water Pollution Management
Wastewater will be generated from boilers in the power plant. Besides, domestic
wastewater from canteen and employees wash area will also be generated.
Adequate treatment of wastewater in ETP prior to recycle/reuse to maximum extent
will be done. Provision of separate storm water system to collect and store run-off
water during rainy season and utilization of the same in the process to reduce the
fresh water requirement will be made. Suitable rainwater harvesting structures will
be constructed.
Noise Pollution Management
Equipments will be designed to conform to noise levels prescribed by regulatory
authorities. Provision of thick greenbelt shall attenuate the noise levels.
Solid Waste Management
Solid waste in the form of ash will be generated in a coal based thermal power
plant. The total ash generated in the plant will be 0.135 MTPA out of which 80%
will be fly ash i.e. 0.108 MTPA and balance will be bottom ash of 0.027 MTPA. The
following measures shall be taken for solid waste management:
In general, ash will be given to potential ash users;
The excess ash will be disposed off using high concentrated slurry disposal
system to HDPE lined ash pond;
The generated waste oil shall be explored to be used in boiler furnace with HFO
or shall be given to authorized recyclers;
The organic portion of solid waste generated in the Sewage Treatment Plant
(STP) will be used as manure in greenbelt development; and
Maintaining the data base on solid waste generation such as quantity, quality,
treatment/management.
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Ash Utilization
Fly ash will be utilized in brick plants, cement industries, as micro-nutrient in
fertilizer, road construction and backfilling of mines. The fly ash will be utilized in
various construction materials to the maximum extent and 100% utilization will be
achieved as per the new fly ash notification.
Greenbelt Development
Additional greenbelt will be developed around the plant site. The total greenbelt
around the power plant complex will be about 13.30 ha (35.96%) upon expansion.
The greenbelt will be maintained with a density of minimum 2500 trees/ha inside
the plant premises. A total cost of Rs. 5 Crores is proposed to be spent for the
development of additional greenbelt.
Cost Provision for Environmental Measures
It is proposed to invest about Rs. 360 crores on pollution control, treatment and
monitoring systems for proposed power plant with a recurring cost of Rs. 26
crores per annum
10.6 Post Project Environment Monitoring Programme
Post project environmental monitoring is important in terms of evaluating the
performance of pollution control equipments installed in the project. The sampling
and analysis of the environmental attributes will be as per the guidelines of
CPCB/SPCB. The frequency of air, noise, surface water and ground water
sampling and location of sampling will be as per the directives of Tamil Nadu
Pollution Control Board.
10.7 Risk Assessment and Disaster Management Plan
The hazard potential of oil and estimation of consequences in case of their
accidental release during storage, transportation and handling has been identified
and risk assessment has been carried out to quantify the extent of damage and
suggest recommendations for safety improvement for the proposed facilities. Risk
mitigation measures based on MCA analysis and engineering judgments are
incorporated in order to improve overall system safety and mitigate the effects of
major accidents.
An effective Disaster Management Plan (DMP) to mitigate the risks involved has
been prepared. This plan defines the responsibilities and resources available to
respond to the different types of emergencies envisaged. Training exercises will
be held to ensure that all personnel are familiar with their responsibilities and
that communication links are functioning effectively.
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10.8 Project Benefits
The proposed 545 MW thermal power plant will result in improvement of
infrastructure as well as upliftment of social structure in the surrounding villages.
The people residing in the nearby areas will be benefited indirectly. The major
benefit due to the proposed project will be in the sphere of generating temporary
employment for substantial number of personnel.
During the erection phase about 50 people on an average will be employed. The
manpower for the proposed expansion of power plant during operational period is
estimated to be about 200 persons in addition to the existing manpower.
Implementation of the power project will result in the following benefits
Employment will be provided to eligible persons both during construction and
operational phase
Temporary employment for people from the neighboring villages during
construction phase.
Community development activities such as training of local unemployed youth
in various construction skills, English speaking, personality development,
development of self help groups for women, providing drinking water facility,
strengthening of rural roads, deepening of ponds etc.,
State will get revenue from payment towards taxes and water cess etc.,
Providing dispensary with a medicine bank to cater to the health care needs of
the surrounding villages.
Providing vocational training to women in areas for their self employment.
Utilizing the services of ex-servicemen for providing training to youth in areas
of personality development, security etc.,
10.9 Conclusion
The proposed expansion of the power plant has certain level of marginal impacts
on the local environment. However, development of this project has certain
beneficial impact/effects in terms of bridging the electrical power demand and
supply gap and providing employment opportunities that will be created during
the course of its setting up and as well as during the operational phase of the
entire project.
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& expansion of existing thermal power plant at Gummidipoondi,
Thiruvallur District, Tamilnadu
Chapter – 11
Disclosure of consultant
Vimta Labs Limited, Hyderabad / Coimbatore 209
11.0 DISCLOSURE OF CONSULTANT
11.1 Introduction
VIMTA Labs Limited is a leading multi-disciplinary testing and research
laboratory in India. VIMTA provides contract research and testing services in the
areas of clinical research, pre-clinical (animal) studies, clinical reference lab
services, environmental assessments and analytical testing of a wide variety of
products.
VIMTA - Environment Division has been in the forefront of its vision to provide
better environment through guiding and assisting the industry for sustainable
development. A stalwart in the mission to protect and preserve the natural
resources on earth for future generations, Vimta offers extensive research and
consultancy services in the field of Environment. With its rich experience, multi-
disciplinary expertise and with the support of its state-of the-art analytical
equipment, the services offered by Vimta are wide ranging and encompasses
entire gamut of Environment Management and Monitoring Services. With its
emphasis on quality services, Vimta, over the years, has evolved itself into a
single reference point in India for Comprehensive Environmental Services.
11.2 The Quality Policy
VIMTA is committed to good professional practices and quality of operations in
its testing, validation and research services.
VIMTA shall ensure customer satisfaction by maintaining independence,
impartiality and integrity in its operations.
VIMTA shall provide the services in accordance with national and international
norms.
VIMTA shall implement quality system as per ISO/IEC 17025 and applicable
GLPs & GCPs, to generate technically valid results/data.
VIMTA shall ensure that all its personnel familiarize with the policies and
procedures of the quality system and implement the same in their work.
11.3 Milestones and Accreditations
1984 - Registered with an initial investment of Rs.2 Lakhs.
1985 - Recognized by ISI (now known as Bureau of Indian Standards).
1987 - Qualified by the criteria of Ministry of Environment and Forests was
notified as one of the 14 standard Environmental Laboratories published in the
Gazettee of India.
1988 - Licensed for carrying out tests on Drugs and Pharmaceuticals.
1990 - Cherlapally land purchased with plans of larger, more comprehensive
facility.
1991 - Accredited by NCTCF, DST, Government of India (the forerunner of
NABL).
1992 - Laboratories shifted to new facility at Cherlapally.
1993 - State-of-the-art equipment worth Rs.60 million procured.
1995 - Accredited by NABL under its revised scheme, certified by Standards
Australia, Quality Assurance Services as per ISO/IEC Guide 25 and ISO 9002.
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1996 - GLP Compliance.
1997 - Restructuring of Vimta from 165 to 100 associates with same
performance.
1998 - Accreditation by GOSSTANDART and joint venture for certification of
Food Exports with ROSTEST, Russia.
2001 - World Bank Recognition.
2002 - ANVISA Brazil certification.
2003 - USFDA accepts Vimta Bioequivalence study report. Showcased Vimta
at AAPS (USA) and ICSE-CPHI (Germany).
2003 - Vimta VHS Research Center inaugurated at Chennai, Launched district
laboratories at Visakhapatnam and Vijayawada, Patient service centers
launched at 160 locations across the country.
2003 – Vimta Labs Recognized by Saudi Arabian Standards Organization.
2004 - Vimta increases people strength from 225 in 2003 to 400 in 2004.
Vimta achieves export turnover of $ 2.5 million.
2004 - Vimta releases its first fortnightly medical newsletter “Vaidyalekha”,
Vimta enters Gulf market - bags a contract for Environmental Consultancy in
Kuwait.
2004 - Vimta acquires 10.7 acres of land in S.P.Biotech Park – Genome
Valley, Hyderabad, to create a world class Research Laboratory of 150000
sq.ft by July 2005.
2004 – Vimta starts a new state of the art speciality services in Molecular
Diagnostics at TICEL Bio-Tech Park” at Chennai.
2006 – Vimta expands its overseas activities. Undertakes environmental
assignments in Saudi Arabia and Tanzania
2008 – Vimta has been Pre-Qualified by World Health Organization (WHO).
2009–Undertaken Comprehensive Environmental Impact Assessment in
Cameroon, Africa
2010 – Accredited by QCI/NABET, Government of India for EIA report
preparation
2011- Undertaking environmental and social impact assessment study in
Tanzania, Africa as per IFC-World Bank Guidelines
11.4 Management and Board of Directors
1. Dr. S.P. Vasireddi Chairman and Managing Director
2. Mrs. Harita Vasireddi Director Projects
3. Mr.V. Harriman Director – Technical
4. Mr. V.V. Prasad Executive Director
5. Mr. S. Subrahmanyam Director
6. Mr. T.S. Ajai Director
7. Dr. Pavuluri Subba Rao Director
8. Prof. D. Balasubramanian Director
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Vimta Labs Limited, Hyderabad / Coimbatore 211
11.5 Services Offered
Spread over the 70,000 Sq.ft lush green garden premises at Cherlapally,
Hyderabad (India), the scientifically designed and meticulously groomed
infrastructural facility of the Central Laboratory of VIMTA has the most
sophisticated instruments backed by an excellent team of professionals. The
40,000 Sq.ft, three-storied, 120 roomed, centrally air conditioned state-of-the-art
Laboratory equipped with Rs.100 million worth analytical instruments and
computerized data management systems, all under one roof is perhaps the only
one of its kind in South Asia in the contract testing and research sector.
Vimta offers various services under the following divisions:
Environment;
Analytical;
Clinical Reference Lab; and
Clinical Research.
The environment division of VIMTA Labs Limited (Vimta) has its presence all over
India including a strong association with international consultants like Japan Bank
for International Cooperation (JBIC), Kennametal Inc. - USA, BBL - UK, Rudal
Blanchard – UK, E&E Solutions – Japan, NEPESCO & KNPC – Kuwait, Marafiq –
Saudi Arabia and others. Vimta has the following credentials:
Recognitions by BIS;
Recognitions by Ministry of Environment and Forests, Govt. of India;
Recognitions by State Pollution Control Boards (wherever applicable) ;
Recognitions by Department of Science & Technology, Govt. of India (NABL) ;
Recognitions by Ministry of Defense, Govt. of India;
Recognitions by APEDA, Ministry of Commerce, Govt. of India;
Recognitions by Saudi Arabia Standard Organization (SASO), Saudi Arabia;
Recognitions from NEMC, Tanzania;
Accreditations by NCTCF;
Certification from Standard Australia;
Recognition from ANVISA Brazil;
Quality Assurance Services as per ISO/IEC 17025; and
Quality Assurance Services as per ICH Guidelines
11.6 Services
Environment essentially being a multi-disciplinary science, the range of services
offered by the Division are also comprehensive and caters to the needs of
industry, pollution control agencies, regulatory authorities and in a larger pursuit
of a green globe. The services under Environmental Assessments include:
Site Selection and Liability Studies;
Environmental Impact Assessments;
Environment Management Plans;
Carrying Capacity based Regional Studies;
Environmental Audits;
Solid and Hazardous Waste Management;
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Vimta Labs Limited, Hyderabad / Coimbatore 212
Risk Assessment (MCA,HAZON,HAZOP) & DMP;
Occupational Health and Safety, Industrial Hygiene;
Environmental Monitoring for Air, Meteorology, Water, Soil, Noise, Ecology
and Socio-Economic;
Industrial Emission Source Monitoring;
Offshore Sampling and Analysis of Marine Water and Sediments;
Marine Ecological Studies;
Marine Impact Assessment;
Rehabilitation and Resettlement Studies;
Forestry and Ecological Studies;
Geological and Hydro-geological Studies;
Land Use /Land Cover Studies based on Remote Sensing;
Socio-Economic Studies;
Due Diligence Studies;
Epidemiological Studies;
Wasteland Management Studies; and
Study on Bio-indicators.
The services under Environmental Chemistry include:
Analysis of Water, Wastewater, Soil, Solid Waste, Hazardous waste as per
Indian and International Codes;
Source Emissions and Work Zone Air/Noise quality monitoring;
Analysis of SVOCs, VOCs, PAH, BTEX, AOX, PCB’s, TCLP metals, TOC etc.;
Categorization of Hazardous Waste; and
Pesticide Residue Analysis.
11.7 Facilities
Vimta-Environment Division is located in scientifically designed Central Laboratory
with the state-of the-art modern facilities to offer vide range of services in indoor
and outdoor monitoring and analytical characterization in the field of
Environment. Further, it is ably supported by highly skilled and experienced team
of professionals in the fields of Science, Engineering, Ecology, Meteorology, Social
Planning, Geo & Hydro-geology, and Environmental Planning.
Besides the regular monitoring equipment such as Respirable Dust Samplers,
Automatic Weather Monitoring Stations, Stack Monitoring Kits, Personal
Samplers, Noise Meters, Portable Water Kits etc, the other major specialized
equipment include:
Monostatic Sodar–Designed by National Physical Laboratory, GOI;
Integrated Noise Level Meter–Quest, U.S.A;
Flue Gas Analyzers–Testo, Germany;
113-A Gravimetric Dust Sampler-Casella, London;
ICP AES– Varian, USA;
Gas Liquid Chromatographs with FID, ECD & pFPD–Varian, USA;
Gas Chromatograph with Mass Detector–Varian, USA;
Atomic Absorption Spectrometer [AAS]–Varian, USA;
PAS-AFC-123 instrument;
Rapid Environmental Impact Assessment for the proposed augmentation
& expansion of existing thermal power plant at Gummidipoondi,
Thiruvallur District, Tamilnadu
Chapter – 11
Disclosure of consultant
Vimta Labs Limited, Hyderabad / Coimbatore 213
High Performance Liquid Chromatograph;
Laser Particle Size Analyzer;
Monostatic Sodar – Designed by National Physical Laboratory, GOI;
Integrated Noise Level Meter–Quest, U.S.A;
Flue Gas Analyzers–Testo, Germany;
113-A Gravimetric Dust Sampler-Casella, London;
ICP AES– Varian, USA;
Gas Liquid Chromatographs with FID, ECD & pFPD–Varian, USA;
Gas Chromatograph with Mass Detector–Varian, USA;
Atomic Absorption Spectrometer [AAS]–Varian, USA;
11.8 Quality Systems
The fact that Environment division and its supporting Site Laboratories are
accredited by NABL (IS0-17025) and Ministry of Environment and Forests and by
other international bodies such as Asian Development Bank (ADB) and World
Bank stands testimony to its emphasis on Quality Systems.
11.9 Achievements
Being the first laboratory to be recognized under Environment Protection (EP) Act
by GOI in 1986, Environment Division with its best mind power and industrial
knowledge competency that allows it to compare with the best in the business.
The Environment Division till date has executed about 350 Environmental
Impact Assessment (EIA) and Environment Management Studies with Risk
Assessment and Disaster Management Plans and obtained statutory
approvals.
Supported by the strong modern laboratory support and experienced hands,
Environment division is well equipped in conducting Due Diligence, Phase-I
and Phase-II studies.
Undertaken specialized studies such as Regional Environmental Impact
Assessment on Carrying Capacity Principle; Upper Air Meteorological studies
using SODAR for major Industrial Complexes.
Associated with prestigious studies such as Environmental Pollution
monitoring around Taj Trapezium, Pre and Post Satellite launch studies for
SHAR, ISRO and monitoring for offshore Oil & Gas exploration for deep-sea
water and sediment sampling.
The services offered include vide spectrum of industries covering Power,
Chemical, Cement, Mining, Steel & Alloys, Metallurgical, Dye & Intermediates,
Bulk Drugs, Pesticides, Agro-Chemicals, Petro-Chemicals, Refineries, Pulp &
Paper, Oil & Gas Exploration & Production, Asbestos, Infrastructure, River
valley, Foundries etc.
The Environment division has also offered its services to major infrastructure
projects such as Ports, Oil & Gas Pipelines, Green field Air Ports, Roads and
Highways.
Rapid Environmental Impact Assessment for the proposed augmentation & expansion of existing thermal power plant at Gummidipoondi, Thiruvallur District, Tamilnadu
Chapter – 11
Disclosure of consultant
Vimta Labs Limited, Hyderabad/Coimbatore 214
DETAILS OF PERSONNEL INVOLVED IN CURRENT EIA REPORT
Sr. No. Name Qualification Position Contribution Experience
1 Mr. M. Janardhan M.Tech (Env) Head & Vice
President(Env)
Co-ordination About 20 years of experience in the field of air quality impacts, and noise,
environmental management and environmental engineering
2 Mr. K.S. Muneeswaran M.E. (Env. Engg)
PGDES, PGDIS
Senior Manager Co-ordination About 22 years of experience in the field of environmental chemistry and
environmental impact assessment
3 Mr. G.V. Raghava Rao M.Tech (Env) Dy. Manager Expert About 11 years of experience in the field of Environmental Impact
Assessment studies
4 Mr. P.Niranjan Babu B.Com Asst Manager Secretarial About 21 years of experience in the field of Environmental Monitoring and
secretarial assistance
5 Ms. Durga Bhavani M.Sc. (Env. Sci) Group leader Expert About 8 years of experience in the field of environmental impact assessment
6 Dr. Subba Reddy M.Sc., Ph.D Scientist Expert About 6 years of experience in the field of Environmental Impact Assessment studies
7 Mr. S. Kishore Kumar M.Tech (Env) Env Engineer Expert About 3 years of experience in the field of Environmental Impact Assessment
studies
8 Mr. S. Rajeswaran M.E., (Env. Engg) Env. Engineer Expert About 3 years of experience in the field of environmental monitoring and
environmental impact assessment
9 Mr. J. Bharatvaj M.E., (Env. Engg) Env. Engineer Expert About 1 year of experience in the field of environmental monitoring and
environmental impact assessment
10 Mr. ACH Ramesh Kumar M.Sc (Env) Scientist Expert About 10 years of experience in the field of Environmental Impact
Assessment studies
11 Mr. T. Seshagiri Rao M.Sc (Env) Scientist Expert About 8 years of experience in the field of Environmental Impact Assessment
studies
12 Dr. Subba Reddy M.Sc., Ph.D Scientist Expert About 6 years of experience in the field of Environmental Impact Assessment
studies
13 Mr. G. Krishnamoorthy M.Sc., (Env. Sci) Scientist Expert About 3 years of experience in the field of Environmental Science and
monitoring
14 Mr. C. Yathavaraj M.Sc., (Env. Sci) Scientist Expert About 2 years of experience in the field of Environmental Science and
monitoring
15 Mr. A. Ashok B.Tech (Biotechnology) Jr. Env. Engineer Expert About 1 year of experience in the field of Environmental Science and
monitoring
16 Mr. T.Karthikeyan B.Tech (Biotechnology) Jr. Env. Engineer Expert About 1 year of experience in the field of Environmental Science and
monitoring
17 Mr. P. Krishna I.T.I (Civil) Sr. Draftsman Cartography About 12 years experience in the field of Environmental and Civil Drawings
18 Mr. J. Ramakrishna I.T.I (Civil) Sr. Draftsman Cartography About 11 years experience in the field of Environmental and Civil Drawings
Rapid Environmental Impact Assessment for the proposed augmentation
& expansion of existing thermal power plant at Gummidipoondi,
Thiruvallur District, Tamilnadu
Chapter – 11
Disclosure of consultant
Vimta Labs Limited, Hyderabad/Coimbatore 215
Rapid Environmental Impact Assessment for the proposed augmentation
& expansion of existing thermal power plant at Gummidipoondi,
Thiruvallur District, Tamilnadu
Chapter – 11
Disclosure of consultant
Vimta Labs Limited, Hyderabad/Coimbatore 216
Rapid Environmental Impact Assessment for the proposed augmentation
& expansion of existing thermal power plant at Gummidipoondi,
Thiruvallur District, Tamilnadu
Chapter – 11
Disclosure of consultant
Vimta Labs Limited, Hyderabad/Coimbatore 217
Rapid Environmental Impact Assessment for the proposed augmentation
& expansion of existing thermal power plant at Gummidipoondi,
Thiruvallur District, Tamilnadu
Chapter – 11
Disclosure of consultant
Vimta Labs Limited, Hyderabad/Coimbatore 218
Rapid Environmental Impact Assessment for the proposed augmentation
& expansion of existing thermal power plant at Gummidipoondi,
Thiruvallur District, Tamilnadu
Chapter – 11
Disclosure of consultant
Vimta Labs Limited, Hyderabad/Coimbatore 219
Rapid Environmental Impact Assessment for the proposed augmentation
& expansion of existing thermal power plant at Gummidipoondi,
Thiruvallur District, Tamilnadu
Chapter – 11
Disclosure of consultant
Vimta Labs Limited, Hyderabad/Coimbatore 220
Rapid Environmental Impact Assessment for the proposed augmentation
& expansion of existing thermal power plant at Gummidipoondi,
Thiruvallur District, Tamilnadu
Chapter – 11
Disclosure of consultant
Vimta Labs Limited, Hyderabad/Coimbatore 221