Lysaghtstown 110kV Substation Construction Methodology

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Lysaghtstown 110kV Substation

Construction Methodology December 2020

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Table of Contents

1. Introduction...............................................................................................................3

2. SubstationConstruction.............................................................................................32.1. MainConstruction.........................................................................................................52.2. WorkingAreas...............................................................................................................52.3. ConstructionVehiclesRequired.....................................................................................52.4. DurationofSubstationCompoundWorks......................................................................62.5. ElectricalInstallationIncludingTransformer..................................................................6

3. Overhead110kVLineConstruction............................................................................63.1. Overview.......................................................................................................................63.2. InstallationofEndMasts................................................................................................83.3. FoundationSizes............................................................................................................93.4. WorkingAreas...............................................................................................................93.5. ConstructionEquipmentRequired.................................................................................93.6. ErectionofEndMast......................................................................................................93.7. DurationofEndMastWorks........................................................................................10

4. AccessRoute............................................................................................................10

5. Earthworks..............................................................................................................105.1. ExcavationandFillWorks............................................................................................105.2. Landscaping.................................................................................................................115.3. SedimentControl.........................................................................................................11

6. ReinstatementofLands...........................................................................................12

7. WasteManagement................................................................................................12

8. ConstructionandEnvironmentalPlans.....................................................................12

9. Summary.................................................................................................................13

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1. Introduction The purpose of this document is to outline the envisaged construction techniques for a 110kV/33kV substation development which will serve a solar farm development in the townlands of Lysaghtstown, Ballyleary, Woodstock and Curragh, Co. Cork. Terra Solar II Limited are seeking a 10-year planning permission for development at Lysaghtstown, Co. Cork comprising a 110kV 4-bay C-type electricity substation (with 33kV customer compound) (including two control buildings, lightning protection, perimeter security fencing, security lighting, drainage infrastructure, temporary construction compound) to connect to and serve a solar farm; associated loop-in infrastructure to tie into an existing 110kV overhead transmission line including underground 110kV cabling and 2 No. new end masts with 110kV line diversion cabling; vehicular entrance and access track from public road; all associated site development works including formation of berms and landscaping. The purpose of the proposed substation and grid connection is to serve a solar farm development in the townlands of Lysaghtstown, Ballyleary, Woodstock and Curragh, Co. Cork. The applications for planning permission for the solar panels, support infrastructure and associated ancillary development works were previously made to Cork County Council under permitted planning references 18/6769, 19/5729 and 19/6882. The facilitation of the proposed substation necessitates some design changes to reference 18/6769 and an application for these changes is being made concurrently to Cork Council for same, as part of a dual consent process. As part of a one project approach, Appendix A of this document contains an Outline Construction Methodology for the concurrent solar farm planning application. This document is intended as an outline construction methodology. Prior to commencement of development, a detailed Construction Environment Management Plan (CEMP) shall be submitted to, and agreed in writing with, the planning authorities, following consultation with relevant statutory agencies. 2. Substation Construction The Lysaghtstown 110 kV / 33 kV substation is proposed within a land parcel of c.56.7 hectares. The proposed substation is located at the centre of this land parcel and will occupy an area of approximately 1.41 hectares. The substation will consist of a compound containing outdoor Air Insulated Switchgear (AIS) equipment comprising busbars, line bays, grid transformers and associated bays, house transformers, two Control Buildings and associated equipment. The size of the substation has been determined by EirGrid’s design requirements. Equipment will include a Supervisory Control and Data Acquisition (SCADA) system, which will allow for off-site monitoring via a communication system. The two 110kV and 33kV Control Buildings will be of blockwork cavity construction complete with slate tiled pitched roofs. These buildings will house both electrical switchgear and control/protection equipment. The 110kV and 33 kV substation Control Buildings are approximately 25 m x 15 m x 7.56 m high and 11.1 m x 10 m x 6.26 m high

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respectively. The existing site profile is gently sloping towards the south east – the contour varies from 86.00mOD to 92.00mOD, rising from the south east to the north west. Site investigations undertaken by Malachy Walsh and Partners on 20th November 2020 indicate that the subsoils in the substation location are not suitable for reuse to establish a structural base for the substation. The site contours suggest that a tiered substation compound will minimise landscape impacts. A compound level of 86.25mOD is proposed for the customer compound, while a level of 89.25mOD is proposed for the Eirgrid compound. A cut/fill operation will be required to ensure a level platform for both compounds. The intent is to retain excavated material on site to form berms, allowing for the most efficient disposal of the excavated material. It is estimated that approximately 22,000m³ of excavation will be required within the site boundary. The volume of imported hardcore will be of the order of 9,300m³. This will be crushed rock to ESB specification. The earth berms will be planted as wildflower meadows, thus increasing the biodiversity value of the land. The Control Buildings will be generally unmanned, with the exception of some infrequent operational visits for inspection, audits and maintenance. Sanitary facilities will be provided for these visits and will comprise a single toilet and wash hand basin for very occasional use, with discharge to holding tanks that will be sized to reflect the anticipated frequency of use. These will be located outside of the fenced area to allow them to be maintained without requiring access. Potable water supply will be from a private well which will be constructed so as to prevent contamination. Thereafter water will be tested and treated as necessary to meet the requirements of the European Communities (Quality of Water Intended for Human Consumption) (Amendment) Regulations 2000. Drainage arising from roof surfaces within the substation and from transformer bunds will be discharged to existing site drainage following passage through an appropriate oil interceptor. A separate substation drainage report is provided in Appendix B. The grid transformer will be located within an impermeable bund capable of oil retention in the event of a total leakage from the transformer. The bund will have a capacity of at least 110% of the volume of oil to preclude any release of contaminants to the environment. A permanent 2.6 m high palisade fence is required for public safety reasons and will be provided around the substation compounds only. Its need arises from the presence within the compound of high-voltage electrical equipment to which public access must be prevented. The colour of the security fencing will be agreed with the planning authority prior to construction. There will be two access gates provided with one accessing each of the 110 kV and 33kV sides of the compound respectively. There will also be internal fences to segregate different areas. When constructed, Lysaghtstown 110 kV Substation will be owned and operated by ESB Networks (ESBN).

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2.1. Main Construction

The project specific programme of works will be proposed and agreed with the Contractor prior to mobilisation on site. The following is a non-exhaustive list of the works to be carried out:

• Verify that all planning and environmental conditions have been satisfied • Site entrance. • Site establishment. • Construction of temporary site drainage works. • Bulk earthworks, including site levelling and entrance road construction. • Existing OHL enabling works. • 110 kV and 33 kV buildings, including foundations works, blockwork,

precast ceilings and pitched roofs. • Construction of transformer compounds. • Permanent foul and surface water drainage works. • Paving • Fencing

• Completion works • Landscaping

All works shall be carried out in accordance with the Building Regulations and up-to-date design codes at the time of mobilisation. A waste management plan will also be implemented to mitigate against undue impacts. 2.2. Working Areas The average working area for construction of a 110/33 kV Substation compound will encompass the footprint of the compound plus an area of 10m outside the proposed post and rail fence. This equates to an approximated area of 18,000m2. This area will be agreed prior to the commencement of works and will be delineated on site. For the duration of the construction phase of the substation, there will be temporary welfare facilities installed. 2.3. Construction Vehicles Required

• 4x4 vehicle • Concrete vibrator • Water pump • Wheeled dumper or Track dumper • Timber or other Shuttering boxes • 360˚ tracked excavator of varying size • Transit van • Delivery trucks

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• Chains and other small tools • Concrete delivered by supplier to closest convenient point • Winch tractor • Tractor and trailer • Crane • Teleporter

2.4. Duration of Substation Compound Works The duration of the substation compound works will be detailed in full and in advance of any construction activities taken place and subject to confirmation. However, it is expected the average duration for the substation compound and building works are as follows:

Civil Works Electrical Works

c.39 weeks c.40 weeks

TOTAL c.75 weeks

A 3 – 4 week overlap of the phases above is envisaged, thus bringing the total construction period to 75 weeks. 2.5. Electrical Installation Including Transformer

A detailed traffic management plan will be implemented for the delivery and installation of the 110 / 33 kV transformer. This will be agreed with the local authority in advance. A waste management plan will also be implemented to mitigate against undue impacts of the electrical installation. There will be other electrical installation works of a lesser scale to the delivery and installation of the 110 / 33 kV transformer. The following is a non-exhaustive list of these works to be carried out: • Delivery and installation of all other HV equipment. • Wiring and cabling of HV equipment and protection and control cabinets. • Commissioning of all newly installed equipment. 3. Overhead 110kV Line Construction 3.1. Overview The proposed Lysaghtstown substation is situated proximate to the 110kV Line. The overhead line runs in a south west to north east direction to the south of the Lysaghtstown substation site. It is proposed to break this 110kV overhead line with the construction of two new end lattice steel line/cable interface end masts approximately 21m in height between the existing pole sets. Generally, these structures will be of similar scale and character to the existing steel lattice masts on other 110kV circuits. The proposed substation will be

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connected to these new overhead end masts by c.574 metres of underground cable. There may be a requirement to modify the existing wooden 110kV overhead line polesets either side of the two newly proposed steel end masts. These modifications will be determined subject to confirmation and agreement with EirGrid prior to the commencement of the substation development. These works will be carried out by EirGrid and the methodology in carrying this out is to be confirmed. The construction techniques carried out will be in line with international best practice and full compliance with all health and safety requirements. In general, the construction phase can be broken down into the following parts: • Verify that all planning and environmental conditions have been satisfied • Pre-construction site investigations including access review and ground conditions • Delineation of any on-site working area (e.g., erection of temporary fencing) • Setting out of end mast foundations and polesets • Site preparation works including minor civil works • Installation of end mast foundations • Erection of end masts • Stringing of conductors and commissioning The existing 110kV line consists of double wood polesets at intermediate locations and steel angle masts where the line changes direction or terminates. The proposed 110kV line connection will be constructed of galvanised steel lattice masts at angle positions. This style of construction is the standard type of construction used for 110kV single circuit lines in Ireland. Prior to commencement of work, the contractor will prepare a detailed Construction and Environmental Plan which will include method statements and work programmes that outline more detailed phasing of the work. This Construction and Environmental Plan will be agreed with the local authority in advance of commencement. The Construction and Environmental Plans will detail access to structure sites, archaeological and ecological sensitive sites (if applicable) and will take account of third party requirements, mitigation measures outlined in the various sections of the Environmental Report and site investigations carried out prior to construction. It should be noted that this outline planning Construction Methodology is indicative and based on the experience in similar transmission line projects. Any issues specific to this project, for example unique planning conditions, will be incorporated fully into the appointed contractor scope of work and careful supervision and management will be carried out to ensure full compliance. The method statements produced by the contractor will be agreed with the appropriate parties. A specialist team will be employed to monitor the construction phase of the project and ensure works are being carried out in accordance with the agreed method statement, safety procedures, pollution control etc.

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3.2. Installation of End Masts All structure locations will be checked for underground services such as cables, water pipes etc. Consultation with the landowner will help to confirm the location of any underground services. If field drains are encountered these will be diverted and all diversions identified to the landowner. The end masts will be set out and pegged prior to foundation excavation. This may require excavation of some existing ditches or drains to allow clear pegging of each individual leg footing for excavation. All such removals are restored upon completion of foundation works. Excavations are set out specifically for the type of mast and the type of foundation required for each specific site. It should be noted that pre-construction site investigations may show that ground conditions unsuitable to the standard foundations are present. In this case a modified, special foundation will be designed. A larger footing may be required in the case of weak soils, pile foundations may be required in the case of deep low strength soils and reduced footing size foundations may be required in the case of rock being encountered at shallow depths. The end mast stubs (lower part of mast leg) will be concreted into the ground. For each leg of the mast (4 in total) a foundation is excavated using a tracked excavator and the formation levels (depths) checked by the on-site foreman. Each of the four corners of the mast will be separately anchored below ground in a block of concrete. Any water in the excavation is pumped out prior to any concrete being poured into the foundation. Concrete trucks shall be brought as close as possible to the excavation to pour directly into the excavation. After this, the concrete shear block or neck is formed using shuttering. In areas of poor ground or high water table it may be necessary to use sheet piles supported by hydraulic frame(s) to prevent collapse of the sides of the excavation and also to prevent the excavation becoming too large. During any dewatering activities a standard water filtration system will be utilised to control the amount of sediment in surface water runoff. During each pour the concrete shall be vibrated thoroughly using a vibrating poker. In the event that sheet piles have been used these are removed (pulled) at this stage. Care is taken not to damage the base members of the mast. The shear block formers are then removed. The end mast foundations are backfilled one leg at a time with the excavated material. The backfill is placed and compacted in layers. All dimensions are checked following the backfilling process. If the excavated material is deemed unsuitable for backfilling, imported fill material may be compacted in layers. When the base construction crew leave site they shall ensure to remove all surplus materials from the site including all unused excavated fill. Once the end mast base is completed and fully set it is ready to receive the mast body which is normally constructed in an area near the foundation site ready to be lifted and bolted into place. The steel for the remainder of the mast is delivered to the site by lorry and various sections

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of the mast, depending on weight and method of construction of the mast, are pre- assembled on the ground beside the end mast before lifting into position. The end mast will be built using a suitable mobile crane. 3.3. Foundation Sizes The average foundation size for each mast leg used on the 110kV transmission system is 4m x 4m x 3.0m. 3.4. Working Areas The average working area for construction of a 110kV end mast will extend 10m all around the footprint of the base of the mast. 3.5. Construction Equipment Required

• 4x4 vehicle • Concrete vibrator • Water pump • Wheeled dumper or Track dumper • Timber or other Shuttering boxes

• 360˚ tracked excavator. • Transit van • Chains and other small tools • Concrete delivered by supplier to closest convenient point • Winch tractor • Tractor and trailer • Crane • Teleporter

3.6. Erection of End Mast The preferred method for constructing the steel angled transmission line end masts is using a mobile crane. The mobile crane will provide optimal construction conditions for the steel mast ensuring that the works are carried out safely. Crane size and weight will be dependent upon the properties of the masts in question with the end mast erection procedure completed in various sections due to the weight of the differing components. End mast sections will be assembled on the ground and lifted into place using the crane.

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3.7. Duration of End Mast Works The average duration of each foundation and mast installation works are as follows: Foundation: 4 weeks Angle Mast: 4 weeks TOTAL: 8 weeks 4. Access Route In order to access the individual substation and associated end mast sites, the contractors will be required to utilise the local public road network. From here, access to the actual site will be via private land. The existing lands on the Lysaghtstown site are in agricultural use. The site will be accessed via an existing farmland track that meets a local road that runs to the north of the subject lands. The existing agricultural entrance and associated track will be widened and upgraded to cater for all traffic to and from the site. All construction traffic will approach the site from the southeast. A detailed analysis of construction access can be found in the site access report which accompanies this planning application. 5. Earthworks 5.1. Excavation and Fill Works The existing site profile for the area of the proposed substation contains a gradual slope where the contour varies from 92m OD (north) to 86m OD (south). An Eirgrid compound level of 89.250m OD and a customer compound level of 86.250m OD will be established. Thus there will be a requirement to relocate up to 22,000m3 of soil to facilitate construction. It is proposed to retain excavated material on site to form berms around the substation compound and wider solar farm site which will provide screening and biodiversity benefits.Site investigations were undertaken by Malachy Walsh and Partners at the proposed substation location on 20th November 2020. These investigations show that excavated material will not be suitable to use as fill for construction of the compound. It is necessary to form berms in appropriate locations around the substation and wider permitted solar farm site to accommodate the excess material. These berms can be formed without any amendments to the permitted solar farm. Formations will be kept a minimum of 2.5 metres from permitted solar farm infrastructure. All proposed berms are set back a minimum of 5m from field drains and 10m back from small flowing watercourses. Classification of excavated soils will be confirmed by testing in accordance with the requirements of “Specification for Road Works Series 600 – Earthworks” prior to placement of materials. Berms will be formed at the locations shown on Macro Works Drawing LD.LYSGHTWN.SBSTN 1.1.

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The slope angle of earth berms constructed from Class 4 should be at an angle of 1V:3H (18.4˚). Steeper angles of 1V:2H (26.5˚) may be used for material that is classified as a Class 2 A/B/C/D. If necessary, geosynthetic reinforcement could be installed in berms to allow for installation to side slope angles of 1V:1H (45˚). Permanent cuttings in Glacial Till at this site should be at an angle of 1V:2H or shallower. For further detail please see the Ground Investigation Report by Malachy Walsh & Partners in Appendix C. 5.2. Landscaping When berms are formed, they will be topped with topsoil and planted with native wildflower/wildgrass seeding mix. A buffer of 5 metres will be maintained from field drains and a buffer of 10 metres will be maintained from flowing watercourses. The formation of berms will be subject to the following methods and work practices:

• Once formed, berms will be well tamped down, rolled and reseeded immediately.

• All berms will be planted with a wildflower/wildgrass seeding mix as soon as formation is complete. Hydroseeding will be implemented to quickly establish grass growth.

• Once seeded, berms will be surrounded by secure silt fencing until grassing over

occurs.

• Earthworks and berm formation will take place in periods of dry weather.

• Machinery working on the berm construction near drains and watercourses will work from the landside or on top of the berm, not on the side adjacent to drains or watercourses.

5.3. Sediment Control A comprehensive audit of the existing drainage network on the overall site will be carried out prior to works commencing, to clearly identify and mark the presence of drainage features including any permanent springs and active (flowing) channels within the site. This mapping will establish where flow originates (springs) and which channels are actively flowing. The purpose of this measure is to (i) avoid direct physical disturbance on these channels that can contribute to sediment loss, and; (ii) ensure that onsite sediment control measures are correctly located and implemented effectively in relation to their location. Any spring risings should be identified as part of these audits using OSI 6-inch mapping as guidance. No berms will be located on top of or within the flow path of any such springs. Freshly excavated spoil will be retained in an area over 5m away from any inactive drain or 10m from an active drain or watercourse (i.e., spring(s); active drains; small tributary). The

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spoil heap will be located on either a well vegetated area surrounded by silt fencing or with the use of containment measures (geotextile mat or bag) and covered to reduce potential for sediment export. A ready supply of these materials will be on site at all times to deal with these eventualities. 6. Reinstatement of Lands Once all works to the substation and end masts are complete, the construction areas will be restored to their original condition or better. Generally, this work is carried out by a specialised agricultural contractor and is carried out in accordance with the relevant IFA agreements and in consultation with the individual landowner. 7. Waste Management All waste arising during the construction phase will be managed and disposed of in a way that ensures the provisions of the Waste Management Act 1996, subsequent amendments/ regulations and any of the relevant Local Authorities Waste Management Plans are satisfied. A Construction Waste Management Plan will be implemented to minimise waste and ensure correct handling and disposal of construction waste streams in accordance with the Best Practice Guidelines on the Preparation of Waste Management Plans for Construction and Demolition Projects, Department of the Environment, July 2009. 8. Construction and Environmental Plans Prior to commencement of development, a detailed Construction Environment Management Plan (CEMP) shall be submitted to, and agreed in writing with, the planning authorities, following consultation with relevant statutory agencies. This plan shall incorporate the mitigation measures indicated in the Environmental Report, and any others deemed necessary, and shall provide details of intended construction practice for the proposed development, including:

• location of the site and materials compound(s) including area(s) identified for the storage of construction refuse;

• location of areas for construction site offices and staff facilities;

• details of site security fencing and hoardings;

• details of on-site car parking facilities for site workers during the course of

construction;

• details of the timing and routing of construction traffic to and from the construction site and associated directional signage, to include proposals to facilitate the delivery of abnormal loads to the site;

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• measures to obviate queuing of construction traffic on the adjoining road network;

• measures to prevent the spillage or deposit of clay, rubble or other debris on the public road network;

• details of appropriate mitigation measures for noise, dust and vibration, and

monitoring of such levels;

• containment of all construction-related fuel and oil within specially constructed bunds to ensure that fuel spillages are fully contained; such bunds shall be roofed to exclude rainwater;

• disposal of construction/demolition waste and details of how it is proposed to

manage excavated soil; A record of daily checks that the works are being undertaken in accordance with the CEMP shall be available for inspection by the planning authority. Monitoring reports shall be submitted to the planning authorities and other relevant statutory bodies in accordance with the requirements of the planning authorities. 9. Summary Construction of the 110kV substation project to serve the permitted Lysaghtstown Solar Farm can be summarized as follows:

• Construction of the substation will consist primarily of an electrical compound to house a transformer, high voltage equipment and two control buildings.

• All substation construction activities will take place at fixed construction sites within

each option location.

• Soil which is excavated to form the compound platforms for the substation will be reused for areas of fill at the same compound and form landscaped berms around the substation perimeter. This will ensure that there will be no requirement to export soil from site.

• The duration of the substation construction works will be confirmed and agreed with

the Local Authority prior to construction. The construction programme is estimated to be a total of 75 weeks.

• Prior to commencement of development, a detailed Construction Environment

Management Plan (CEMP) shall be submitted to, and agreed in writing with, the planning authorities, following consultation with relevant statutory agencies.

• All planning conditions will be complied with and contractor(s) will be supervised and

managed closely to ensure full compliance.

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AppendixA Outline Construction Methodology for a Proposed Solar Farm at Lysaghtstown, Co. Cork. Please note that this document is being submitted for information only. Planning permission is being sought for design alterations to permitted solar farm reference 18/6769. These alterations are to facilitate substation construction. This OCEMP is included so that a full assessment can be made of the entire proposed development.

August 2018

Outline Construction and Environmental

Management Plan

PV Solar Farm

At Lysaghtstown, Co. Cork

August 2018

Document Control Sheet

Client Terra Solar II Limited.

Project Title Proposed Solar Farm at Lysaghtstown, Co. Cork

Document Title Outline Construction and Environmental Management Plan

Document No. RPT_201124_Lysaghtstown OCEMP

Document Comprises

DCS TOC Text Appendices

1 1 1 1

Prepared by DT Checked by CF

Rev. Issue Date

2 14/12/20

Outline Construction Environmental Management Plan 1

1 Introduction ......................................................................................................... 3

1.1 Context ...................................................................................................................................... 3

1.2 Scope ........................................................................................................................................ 3

1.3 Site Location .................................................................................................................................... 4

1.4 Development Description................................................................................................................ 4

2 Construction Works ............................................................................................ 4

2.1 General ...................................................................................................................................... 4

3 Construction Management ................................................................................. 7

3.1 Construction Timeline ............................................................................................................. 7

3.2 Phasing ..................................................................................................................................... 7

3.3 Site Compound....................................................................................................................... 10

3.4 Traffic Management ............................................................................................................... 11

3.4.1 Delivery Route ................................................................................................................................... 11

3.4.2 Site Entrances .................................................................................................................................... 14

3.4.3 Description of Solar Components for Delivery ................................................................................ 14

3.5.3.1 Road Signage and Cleaning ............................................................................................................. 15

3.5.3.2 Delivery Co-ordination ...................................................................................................................... 15

3.5.3.3 Construction Personnel .................................................................................................................... 16

3.5.3.4 Access Control .................................................................................................................................. 16

4 Health & Safety ................................................................................................. 16

4.1 General .................................................................................................................................... 16

5 Construction & Demolition Waste Management Plan .................................... 17

5.1 Waste Management General ................................................................................................. 17

5.2 Wastes Arising & Management ............................................................................................. 17

5.3 Documentation of Waste ....................................................................................................... 18

5.4 Hazardous Material ................................................................................................................ 19

6 Environmental Management ............................................................................ 19

6.1 Existing Ecology .................................................................................................................... 19

6.2 Soil Structure Protection ....................................................................................................... 19

6.3 Material Excavation and re-use on site ................................................................................ 20

6.4 Construction of Access Tracks ............................................................................................ 21

6.5 On-Site Surface water generation and drainage ................................................................. 21

6.6 Substation and Associated Earthworks ............................................................................... 22

6.6.1 Excavation and Fill Works ................................................................................................................ 22

6.6.2 Landscaping ...................................................................................................................................... 22

6.6.3 Sediment Control .............................................................................................................................. 23

7 Noise Management ........................................................................................... 23

8 Air Quality ......................................................................................................... 23

9 Archaeology ...................................................................................................... 24


10 Reinstatement of Excavated Material after Construction Stage .................... 24

11 Operational Site Management and Maintenance ............................................ 25

12 Decommissioning and Restoration ................................................................. 25


1 Introduction 1.1 Context This Outline Construction and Environmental Management Plan (OCEMP) is prepared to support a planning application for design alterations to a previously permitted ground mounted solar farm by Terra Solar II Limited at Lysaghtstown, Co. Cork, Cork County Council Reference 18/6769 refers. Specifically, the application relates to an 8.04 ha subset area of that application site area (56.7 ha). As outlined in detail below, the basis for the proposed design changes arises from the intention to develop a new 110kV substation and associated loop-in infrastructure to overhead transmission lines at this location in lieu of the 38kV substation previously permitted under planning reference 18/6769. This 110kV substation and loop-in is the subject of a separate planning application to An Bord Pleanála. This document is also submitted with the application to the Board on the basis that it considers construction interactions between the solar array and substation/grid connection as part of a one project approach. An OCEMP was submitted with the solar farm application under reference 18/6769. This document represents an update to that statement, as it relates to the subject design changes.

The purpose of the document is to outline key details in relation to the environmental measures to be implemented on site to prevent any potential impacts of the project’s construction on the surrounding environment. The objective of this OCEMP is therefore to identify the potential issues which are relevant to the project, to address these issues and to provide solutions which are satisfactory to all concerned.

A main contractor will be appointed by the developer to construct the development. This contractor will be responsible for the preparation and implementation of more detailed construction and environmental management plans to guide the installation of any approved solar farm. These plans will appropriately consider and incorporate all identified and/or conditioned measures which emanate from the planning phase of the project and will include detailed Risk Assessed Method Statements (RAMs) for all aspect of the works associated with the development of the solar farm. 1.2 Scope This OCEMP represents a high-level overview of planned construction methods which has been prepared as a general assessment aid, recognising the relative new nature of solar PV technologies and associated proposals in Ireland. As highlighted, it includes a commitment that a more substantive construction and environmental management plan will be prepared and agreed with the Council prior to commencement of any development. The OCEMP specifically details how the Project team will implement and conduct its allocated site management responsibilities during the various stages of the proposed development. A fundamental aim of an OCEMP is to ensure all construction is properly facilitated, integrated and coordinated so as to deliver certainty to the objectives of the Project. The Plan provides a holistic approach that:

• Advises how the project management team will comply with the requirements of the contract relating to construction

• Defines the project objectives and targets of particular relevance to the construction phase • Describes constraints specific to the construction phase and the project in general • Describes the process for the identification and control of risks specific to the construction

phase • Describes the proposed strategy for the construction phase, with particular regard to

establishment, resourcing, site organisation and construction controls.


1.3 Site Location The proposed solar farm is located at Lysaghtstown, Co. Cork within the planning remit of Cork County Council. The subject lands, which are currently in agricultural use, are located 3.5km northwest of Midleton town centre and approximately 3km north of the East Cork Parkway (N25). The subject site is approximately 8.04 hectares in area, with access from the L-7634 road to the south. Irregular in shape, the site consists of 3 different agricultural fields which are currently used primarily for agricultural cropping. 1.4 Development Description Terra Solar II Limited intend to apply for a 10 Year Planning Permission for a solar farm consisting of circa 14,600 m2 of solar panels on ground mounted frames, 2 no. single storey electrical inverter/transformer stations, battery storage container, battery control unit, security fencing, satellite pole, CCTV, access tracks, upgrade to existing agricultural field entrance, temporary construction compound, landscaping and all associated ancillary development works. The proposed development is a partial change of plan from that previously permitted under Cork County Council planning reference 18/6769 and will provide for the omission of the previously permitted 38kV substation and a net decrease in panel area of circa 10,800 m2. Construction and operational access will be via the L-7634 at Lysaghtstown, Co. Cork. The operational lifespan of the solar farm will be 35 years.

Figure 1 - Site Location Map

2 Construction Works 2.1 General The civil works for the panels themselves use a simple, ground-mounted system that avoids undue ground disturbance and works with the existing site topography. The PV panels will sit on angled racks comprised of galvanized steel arranged in portrait or landscape configuration depending on the final


system deployed1. It is envisaged that these will be screw or driven-piled following geotechnical assessment2. The panels will be positioned on the rack at a minimum height of 0.9 m above the ground and rise to a maximum height of up to 2.8 m. The PV panels will be orientated to the south in order to capture maximum solar energy. The panels will be positioned at a tilt angle of up to 30 degrees from the horizontal having regard to natural site topographical and orientation conditions to ensure the best solar absorption. The panels will be stationary with no movable parts. The proposed reconfiguration of the solar array layout comprises the removal of panels in the area of the intended 110kV substation, with further minor modifications in the area of the planned ‘loop-in’ connection to the existing overhead lines. It is proposed to relocate some of the removed panels to the site of the previously permitted 38kV substation east of the L-7634. Collectively, these changes will result in a net decrease in panel area of circa 10,800 m2 on that permitted under planning reference 18/6769. 2 no. inverter/transformer stations are incorporated into the layout to convert direct current generated by the PV panels into alternating current which can be subsequently used by the electricity network3. These units are manufactured offsite and delivered installation ready. These will either be combined or standalone separate units with a maximum floor area of approximately 29.8 m2. Provision is also made for a single battery storage container and battery control unit. A 4m wide compacted gravel access track will provide internal access to the solar arrays and associated infrastructure. A perimeter fence up to 2.8 m in height will be erected to provide security and restrict unauthorised entry. This fence will be stock proof in nature, sympathetic to the agricultural character of the site. The footings for the fence will either be pre-moulded or localized in-situ concrete, to be determined once a contractor is appointed. The installed fencing will incorporate mammal friendly access, with a minimum 200 mm gap retained at the bottom between the fence and the ground, as per the submitted technical plans. It is proposed to access both site parcels via the entrances permitted under planning reference 18/6769. The entrance to the west of the L-7634 will be widened to circa 19 metres to ensure it appropriately caters for future delivery of the 110kV substation plant/apparatus. The adjoining hedgerows in ownership in the vicinity of these entrances will be maintained to facilitate appropriate sightlines. In terms of the landscaping proposals, there are no additional hedgerows proposed compared to the permitted application. The only change is the removal of c.10m of existing hedgerow and one mature tree at the proposed site entrance to facilitate the site entrance track. Approximately 50m of internal hedgerow will be trimmed back along its northern verge to facilitate the proposed access tracks. The existing hedgerow is to be bolstered along its southern side with a native whip planting mix as per Hedgerow Type 1. The proposal will contribute directly to a carbon dioxide emission reduction of 12,937 tonnes per annum or the equivalent of 452,795 tonnes of CO2 over the 35-year lifetime of the project.

1 Refer to technical drawings SD-1016 and 1017 for panel and array system options. Final technical specification to be agreed

with Cork County Council prior to construction. The final design will be subject to standard micro-siting arising from site survey

work. 2 The exact nature of the foundations will be determined at detailed design stage. Other alternative foundations arrangements

include ballasting systems and piles. Final foundation type will be confirmed with Cork County Council prior to construction. 3 The total number of inverter/transformers permitted under reference 18/6769 was 15. This will be reduced to 14 as part of the

proposed amendments application.


Substation and Loop-in Grid Connection The solar farm will connect to the existing overhead electricity lines which traverse the site via a direct ‘loop-in’ from the proposed 110 kV substation. As outlined, the substation and associated loop-in infrastructure to tie into the existing overhead transmission line will be the subject of a separate planning application to An Bord Pleanála. Notwithstanding this dual consent process, this report considers the full combined development for the purposes of completing a robust assessment of the entire project. The substation proposal is delineated in accompanying drawings and reports prepared by Malachy Walsh and Partners and Terra Solar II Limited. The 110kV substation involves two separate compounds namely (i) the 110kV compound which will be in the ownership of ESB Networks and (ii) the 33kV compound which will be in the ownership of the customer. Please refer to the enclosed drawings by Malachy Walsh and Partners for site configuration and design layout. The main construction elements will be two substation buildings of concrete block construct with slate roof, electrical infrastructure, plinths, bunds, lightning masts, surface water and foul drainage works and lighting. The compound facility will be secured with fencing to full EirGrid specification. Cables connecting the substation to the associated solar farm development will be underground to a depth of approximately 1 m. Existing site levels will be reprofiled for the purposes of accommodating the substation following detailed pre-commencement site investigations. In order to connect the substation to the transmission network, it is proposed to break the existing 110kV overhead line and divert it underground via two new end mast steel lattice structures of approximately 21 m in height. These new masts will allow for approximately 574m of new underground cable which will be routed into and out of the substation. This connection method will constitute a new node of the transmission network, connecting the proposed substation and associated solar farm generation to the National Grid. An outline construction methodology for the 110kV substation and loop-in infrastructure is enclosed with the application. All works will be undertaken to Eirgrid and ESB Networks specification and in full compliance with environmental and other mitigation measures contained in the final Construction and Environmental Management Plan. The main civil works of a solar farm are therefore limited to:

• Internal track. The track which provides direct access to the solar arrays consists of compacted gravel. It allows in particular small vehicular movement during the operation of the PV plant. For its preparation, a thin layer of topsoil shall be removed before construction build-up is placed.

• Cable trenches. Narrow cable trenches to a depth of about 1.0 -1.5m will be excavated during construction, where required, but will not be visible after the construction is finished. Underground cabling will be typically confined where possible to the access track to avoid undue soil disturbance in accordance with best practice measures.

• Erection of PV arrays, prefabricated inverter/transformer stations. Piling of frame structures and mounting of panels. The inverters/ transformers come to the site as prefabricated, ready to install elements.

• Perimeter Fencing. Secure perimeter fencing will be required as indicated on the planning drawings. This will be stock proof fencing (up to 2.8 m high) with support poles located at approximately 2.5m centres. The footings for the security fencing will be precast or localised in-situ concrete. All final detail for the foundation elements will be developed with the contractor at construction stage. Typical plan details for this fencing and CCTV installations are provided as part of this application.

• Substation and Grid Connection. Construction of substation and associated ‘loop-in’ infrastructure. This infrastructure will be taken in charge by the ESB and constructed in


accordance with their specifications, to be informed by detailed pre-commencement method statements.

3 Construction Management 3.1 Construction Timeline

The construction of the solar PV arrays and substation will comprise two distinct stages, namely, (1) the construction of the substation and grid connection infrastructure which will be the only construction activity on the site in the first 42 weeks, and (2) the follow on construction for the solar farm arrays, including electrical commissioning of the substation which will run in parallel. As outlined in Figure 2, the entirety of the construction stage will take place within a timeframe of approximately 75 weeks.

Figure 2 – Indicative Construction Programme 3.2 Phasing Throughout these two stages, in terms of the Delivery and Phasing of Development the following are typical construction phases:

Week 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27

Enabling Works

Civil Works

Electrical Works

Pre-commissioningESB Commissioning

Site setup

Solar Farm Installation

Electrical Commissioning

Close Out

CONSTRUCTION PROGRAMME

Substation

Construction

Substation

Electrical

Solar Farm

Week 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55

Enabling Works

Civil Works

Electrical Works

Pre-commissioning

ESB Commissioning

Site setup



Close Out

Substation

Construction

Substation

Electrical

Solar Farm

CONSTRUCTION PROGRAMME

Week 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20

Enabling Works

Civil Works

Electrical Works

Pre-commissioning

ESB Commissioning

Site setup



Close Out

Substation

Construction

Substation

Electrical

Solar Farm

INSTALLATION/COMMISSIONING PROGRAMME*


Site Set Up This task will take up to c.2 weeks to complete and will involve constructing a 4-metre-wide compacted gravel access track, and the establishment of temporary construction compounds. The construction of the access track will require the removal of a strip of topsoil, with the outer edges being re-filled following the laying of the gravel. The excavated topsoil will be redistributed across the temporary site compound area following construction to address wear and tear from construction activity. The construction compound for the south of the L-7634 will be established initially only, with the second construction compound for the solar farm to the north of the L-7634 established subsequently in week 43. The location of these compounds is identified in Figure 3. They were previously agreed under permitted reference 18/6769.

Figure 3 – Proposed Location of Temporary Site Compounds The perimeter fence will be constructed of stockproof fencing and will be 2.8 m in height, with mammal access facilitated by way of a minimum 200 mm gap between the erected fence and ground. The access gates will be designed in accordance with standard guidelines for the provision of mammal access (e.g. NRA 2008). The perimeter fence will be set back approximately 5 m from the centreline of the surrounding ditch/hedgerow. Construction of 110kV Substation The construction of the substation and associated compound will begin with the regrading of the existing ground profile via cut and fill. The substation buildings of concrete block construct with slate roof will be erected and work advanced on the electrical compound configuration, plinths, bunds and drainage proposals. The compound facility will be secured with fencing. Substation Electrical Works This process will run between week 56 and week 75 approximately and comprise the installation of 110kV switchgear, control room equipment, control and protection equipment and all necessary cabling. Installed plant will be wired using switchgear panels, distribution boards and battery systems.


Excavation and Fill Works The existing site profile for the area of the proposed substation contains a gradual slope where the contour varies from 92m OD (north) to 86m OD (south). An Eirgrid compound level of 89.250m OD and a customer compound level of 86.250m OD will be established meaning there will be requirement to relocate up to 22,000m3 of soil to facilitate construction. It is proposed to retain excavated material on site to form berms around the substation compound and wider solar farm site which will provide screening and biodiversity benefits. Phase 2 – Solar Array Installation and & Electrical Commissioning Works: Setting out Cable Trenches and Civil Works This task will run in tandem with the installation of the PV panels. The laying of cables will require the excavation of narrow trenches to 1.0 – 1.5 m depth, however these will be refilled immediately following pipe laying. The 14 no. inverters/transformer stations will be manufactured offsite and delivered installation ready4. These will either be combined or standalone separate units with a maximum floor area of c.417 m2. Subject to final specification, this unit will either be mounted on blocks or laid on pad foundations of shallow depth. Installation of Solar PV Panels The erection of frames and mounting of Solar PV panels will take c.8 weeks to complete. The solar PV panels are mounted on supporting structures, in the form of metal frames, which are typically anchored by driven or screw piles to a depth of up to 2 m, causing minimal ground disturbance and occupying less than 1% of the land area. The angled racks will be anchored to the ground using one of the following methods:

• Screw piles or rammed piles: This is the preferred method of founding the racks, as it is the quickest to construct and most economical. This can be considered the default method and it is expected that the vast majority of the site will use screw or rammed piles as anchors;

• Pre-drilled holes with backfilling/concrete: In certain cases, geotechnical conditions such as the presence of rock close to the surface may require foundation holes to be pre-drilled prior to ramming the piles. These holes would then be backfilled with concrete or other aggregate. A pre-construction geotechnical assessment will confirm if this type of anchor is required. It is expected that this would only be deployed in localised pockets of land where rock was present, if at all;

• Ballast foundations: This foundation type can be used in localised circumstances where penetration of the ground surface is not possible. This method uses concrete anchors to counteract any lift forces generated by wind loading on the modules. Ballast foundations could be deployed in areas of the site in the event of rock near the surface, or where there is potential for sub-surface archaeology.

With the exception of a specific scenario where pre-drilled holes are necessary, there are no concrete works required in the installation process. The anchoring of panels will be followed by DC cabling, connections to inverters/transformers and a period of associated testing. This task will take c.3 weeks to complete. The perimeter fence will be constructed of stockproof fencing and will be 2.8 m in height, with mammal access facilitated by way of a minimum 200 mm gap between

4 Within this, there are 3 no. single storey electrical inverter/transformer stations, a battery storage container and a battery

control unit in the defined subject planning application red-line.


the erected fence and ground. The access gates will be designed in accordance with standard guidelines for the provision of mammal access (e.g. NRA 2008). The perimeter fence will be set back approximately 5 m from the centreline of the surrounding ditch/hedgerow. Reinstatement of Excavated Materials/ Landscaping This task will take place at periodic intervals over c.5 weeks to complete and will involve the reinstatement of all the excavated materials and associated landscaping works. The reinstatement will include the placement of topsoil as required, for example:

• Areas of disturbed ground; • Exposed substrata areas as a result of the construction works; • Adjacent access tracks; • The construction compound and other temporary works areas and redundant features which are

not required as part of the permanent works. Pre-commissioning/Commissioning The pre-commissioning survey work will be completed comprising the inspection of all electrical equipment, earthing and bus wiring. All relevant site tests will be completed, including conductivity, resistance, timing and other mechanical operational checks. Follow on commissioning tests will then be completed ahead of energization of the substation. 3.3 Site Compound As stated in Section 3.2, temporary site compounds shall be provided as shown in the example in Figure 5. It will include the following facilities at a minimum:

• Adequate canteen space to allow for all workers during the peak period. • Office space with lighting, heating and internet facilities. • A diesel generator to provide sufficient capacity for all facilities. • Toilets and adequate welfare facilities for construction staff in accordance with the relevant

statutory Health & Welfare guidelines. • Parking space for both light and heavy vehicles. • Temporary Storage Area

Figure 5 – Indicative Typical Site Compound Layout (refer to drawing no. 5262-1014


The final configuration of the construction compound will be tailored to the site and will be agreed with the Council prior to commencement of development. The location of this temporary facility has been considered as part of the design of the proposal, the layout of which will include a geotextile base and silt fencing as part of environmental controls. The proposed locations for the temporary construction compounds are shown in Figure 4. On completion of the construction stage the compound areas will be returned to grassland, it is not intended to incorporate these areas, at any stage, into the solar array area.

All relevant statutory welfare facilities will be provided as part of the temporary construction compound, including canteen facilities and drinking water supply, toilet, wash up and locker facilities, first aid facilities and offices for site engineers and contractors.

Portable toilet and wash facilities will be provided from a licenced sanitation supplier bound by Environmental Protection and Health & Safety legislation. Toilets will be serviced on a weekly basis or where necessary, according to type. A record of servicing will be kept by the operator. Wastewater effluent will be collected and disposed off-site in accordance with the principles contained in the Environmental Protection Act (Duty of Care) Regulations 1991.

Washing and changing areas will be located adjacent toilet facilities and a supply of clean warm and cold water maintained where reasonably practicable. Soap and other means of cleaning and towels or other suitable means of drying will be provided and replenished as part of servicing arrangements by the licenced sanitation supplier. All waste water will be collected and removed from the site. Sufficient ventilation and support lighting will be provided.

A supply of drinking water will be stored and made readily available. Rest facilities will provide shelter from wind and rain. These will have adequate numbers of tables and seating, a means for heating water for drinks and for warming up food will be provided. Rest areas will not to be used to store plant, equipment or materials.

Please note there is no requirement for potable water or wastewater treatment facilities as part of the constructed operational development.

Figure 6- Sample Welfare/ Sanitation Facilities and Servicing

3.4 Traffic Management 3.4.1 Delivery Route The delivery route options were previously assessed under reference 18/6769 by Civil and Structural Advisors Ltd. These are detailed in the Site Access and Drainage Study that accompanies this application. The methodology for the access study included: a desk top study of historic records for


the site; a site walkthrough with visual inspection; a site drive-through with a GPS enabled dashboard camera; a detailed review of horizontal and vertical geometry in relation to the vehicles proposed for construction stage and a discussion with the Cork County Council Area Engineer to ensure local issues were considered in detail in the preparation of this report. The identified delivery route commences at the Port of Cork at Ringaskiddy and follows along the N28, N40 and N25 National Roads. The analysis undertaken in the Site Access Study shows that this route poses no challenge to articulated vehicles. Two delivery route options were considered in the Site Access Study for the stretch from the N25 junction, along local roads to the site (ref Figure 7):

• Option 1a (N25, L7642 (Hedgey Boreen), Carrigane Road, Local Road L7634 to Site) and • Option 1b (N25, Water Rock Road, Carrigane Road, Local Road L7634 to Site).

To access these local routes, two junctions off the N25 were considered: L7642 / N25 junction and the Water Rock Road / N25 junction. The Site Access Study shows that no works are required to the public road network to facilitate the passage of an articulated vehicle from the N25 to the Site.

Figure 7: Delivery Route Options 1a and 1b The Site Access Study found that the L7642 (Hedgey Boreen), Carrigane Road and Water Rock Road were in good condition with no significant pavement nor drainage defects noted. The L7634 Local Road was found to be in poor condition though it is noted that localised resurfacing has been undertaken in a small number of areas. Based on the detailed site observations and the discussions with the Area Engineer Personnel, it is recommended that the L7634 local road be resurfaced as part of the Solar Farm works from the junction of the L7634 with the Carrigane Road and the third site entrance (excluding those localised areas where resurfacing has already been undertaken). The surfacing specification shall be agreed at detailed design stage with the Area Office. Roadside drainage shall be improved as part of Cork County Council’s current programme of roadside drainage improvements in the area.


These were proposed and accepted as the best routes to the site by the Cork County Council under references 18/6769. The Site Access Study found that there were no locations on any of the routes surveyed where the gradient exceeded 14% (maximum gradient permitted in the guidance documents) and no significant crests nor dips in the existing alignment were found. The existing horizontal geometry was also found to be generally adequate. The construction phase of the solar farm and substation/grid connection is estimated to be 55 weeks long. In this period, the average number of vehicles per day accessing the site is estimated to be 15. The 55-week construction period shall be followed by a 20-week installation and commissioning period. In this period, it is estimated that the average number of vehicles per day accessing the site shall be 5 and the majority (60%) of these vehicles shall be cars and vans. The Site Access Study notes that once the construction phase is complete, the traffic associated with the proposed solar farm would be a reduction in the existing traffic volume associated with the site’s present use.

Figure 8a – HGV Vehicle Details

Figure 8b – HGV Specification of the Delivery Vehicles


3.4.2 Site Entrances Two site entrances are proposed in the Site Access Study as it relates to the subject application. The entrance to the east of the L7634 is as permitted under reference 18/6769. It is proposed to widen the entrance to the west of the local road to 19 m to accommodate larger HGVs necessary for the delivery of plant to the substation. c.10m of additional existing hedgerow and one mature tree will be removed at this entrance to facilitate this. The layouts for these entrances is based on Swept Path Analyses and details are provided in the submitted drawings by Malachy Walsh & Partners. Current visibility distances at the entrance locations are in excess of 70m and it is proposed to maintain these standards as part of the construction works and operational development. As detailed elsewhere in this document, all site delivery activities will be informed by suitably devised safe systems working arrangements, including intermittent delivery sequencing to mitigate any build-up in traffic congestion and the use of traffic/speed controls on approach including warning signs and flagmen, to be agreed with the Council prior to development as part of the final Construction and Environmental Management Plan, complete with Traffic Management Plan. 3.4.3 Description of Solar Components for Delivery The solar panels and ancillary components are relatively small and are transported in pallets before being assembled on site. The panels comprise of high transmission, low iron, tempered glass and each panel weighs approximately 20 kilograms and typical dimensions are 1640mm x 995mm x 40mm. A 40-foot cube container can carry approximately 28 pallets of panels, which equates to approximately 728 panels, weighing almost 15 tonnes. Therefore, the gross load will be approximately 18 tonnes, which is significantly lower than the maximum permitted load of 24 tonnes for laden vehicle transportation with a combination of a two-axle tractor unit with a two axle semi-trailer. This value is obtained from the Road Safety Authority Guidelines on Maximum Weights and Dimensions of Mechanically Propelled Vehicles and Trailers, Including Manoeuvrability Criteria. Ancillary components such as switchgear and inverter panels will be housed in units and easily transported to site using medium articulated trucks also during the construction phase. 3.4.4 Traffic Volumes The construction and installation stages are anticipated to take approximately 75 weeks. Materials will be delivered by Heavy Goods Vehicles (HGV) and it is anticipated this will equate to approximately 5,424 HGV deliveries during this time, or an average of c. 13 trips per day5. This is the full project daily average. As outlined above, the average daily trips for the separate construction and subsequent installation/commissioning stages are 15 trips and 5 trips, respectively. The largest single component of expected traffic volumes is the delivery of gravels to site for the access track and more significantly the importation of fill for the construction of the substation. Provision is also made for 10% contingency in traffic volumes as part of a precautionary approach. Over 60% of trips for the installation/commissioning stage will be undertaken in car-van type vehicles. Onsite construction staffing numbers will vary over the construction period reaching a peak of 75 workers during the construction stage and a peak of 10 during the installation/commissioning stage. Staff will access the site using light vehicles (cars/mini-buses), and car parking facilities will be available on site to ensure that traffic flows on the local road network in the vicinity will not be impeded during construction. Car-pooling for staff will be encouraged for the duration of the project. Adequate on-site parking is provided for within the temporary construction compound.

5 Based on 5.5 working days for a 75-week period representing the worst-case scenario.


3.4.5 Traffic Access

Access and egress to the site will be controlled by the project manager. Access to the subject site will be taken via the existing access off the L-7634 road. On site vehicle tracks will be used to access the inverter/transformer stations and on-site substation which will consist of compacted gravel. These tracks will be principally used during the construction phase with occasional access for routine maintenance during the operational period. All suppliers undertaking deliveries to the site will be informed of the delivery arrangements and restrictions. The number of construction staff on site will vary over the construction period depending on the activity that is taking place. The majority of staff are expected to share vehicles when travelling to and from the site, or travel in crew buses. Staff vehicles will also follow this designated local route, to gain access to the site. 3.4.6 Abnormal Load In addition to standard articulated vehicles permitted under the solar farm, the proposed substation will require a single abnormal load delivery to transport the substation transformer to the site. An autotrack analysis of this tractor/trailer vehicle which focuses on narrow junctions and turns closest to the site can be found in the site access report which accompanies this planning application. The autotrack show that the abnormal load can negotiate the local road to the site and access at the proposed site entrance. Delivery measures for this vehicle will be agreed with Cork County Council in advance which are consistent with abnormal loads for electricity infrastructure projects.

3.5.3 Management Measures 3.5.3.1 Road Signage and Cleaning: Appropriate warning signs adopted from Chapter 8 ‘Temporary Traffic Measures and Signs for Roadworks’ – Road Signs Manual will be erected to advise motorists and others of works affecting the public roads. Mitigation measures will also be put in place to ensure that public roadways are kept free of mud, dust and debris at all times. Such measure will be described in the final construction management plan provided by the contractor prior to construction.

Figure 9 – Sample Road Signage

3.5.3.2 Delivery Co-ordination: Deliveries of bulk materials such as hardcore, concrete and solar panels will be managed and co-ordinated to minimise disruption to local traffic and activities. In particular these will be scheduled to avoid activities which would attract significant traffic.


3.5.3.3 Construction Personnel: Standard working hours for construction will be 8.00am to 6.00pm Monday to Friday and 8.00am to 4.00pm on Saturday (if required). Construction traffic will not pass through any local towns or villages. All site personnel will be required to wear project notification labelling on high visibility vests and head protection so that they can be easily identified by all workers on-site.

3.5.3.4 Access Control: A staff presence will be maintained at the site entrance during working hours. One of the functions will be to log all incoming vehicles and personnel and ensure no unauthorised access is permitted.

As an unmanned facility, the proposal will actively give rise to a reduced number of vehicular movements to/from the site once operational, improving the carrying capacity of the road network locally. As such, prospective traffic impacts arising from the development will largely be limited to the short 34 week construction stage. Further to this, a detailed Traffic Management Plan will be prepared at the pre-commencement stage that will facilitate the safe operation of the existing entrance during the construction stage to address and mitigate any concerns arising.

4 Health & Safety 4.1 General As required by the Safety Health and Welfare at Work (Construction) Regulations 2001-2006, a Project Supervisor Design Process (PSDP) will be appointed by Terra Solar II Limited to co-ordinate the design effort and to address and minimise construction risks during the design period. Notification of this appointment will be sent to the HSA by means of their Approved Form 1 (AF1). As design advances and before tender stage, a Preliminary Health and Safety Plan will be drawn up by the PSDP and reviewed by the project team.

This will then be issued with the tender package(s) and ultimately will be passed on to the appointed Project Supervisor Construction Stage (PSCS) to be developed into a full project Health and Safety Plan. Notification of this appointment and the commencement date of construction will sent be to the HSA by means of their Approved Form 2 (AF2).

The construction areas will be delineated and will be under the control of the PSCS who will co-ordinate and supervise all safety aspects of the project. A Safety File will be compiled and maintained on site for the duration of the project and this and the implementation of the Plan will be subject to regular audits.

The main contractor will engage the services of a safety consultant to prepare a site specific health & safety plan, carry out safety risk assessments, notify the HSA of commencement, and carry out audits of the site. All personnel and their subcontractors who will be working on or attending site will attend and comply with a Site Safety Induction Course to be provided by the Site Safety Officer. All contractors will be requested to provide a sound working environment for all employees involved in the design, construction and operation of the proposed solar farm. This shall take into account all applicable national laws, guidelines and standards. The Contractors must ensure that the following HSE objectives are met:

• Zero accidents and injuries with respect to all involved workers. • Zero harm to workers, the public and the environment.

Each Contractor shall prepare and implement the Health, Safety and Environmental (HSE) Plan and associated working instructions and procedures that will govern the contractor’s actions at all times. The HSE Plan will cover the following aspects:

• Project Policy Statement. • Roles and Responsibilities.


• Site regulation, including, for example, housekeeping, barricades, excavations, tools and equipment, electrical work, ladders and scaffolds, etc.

• Risk Management and Hazard Identification. • HSE training. • HSE management of subcontractors. • Work Permit system. • Personnel Protective Equipment (PPE). • Inspection and auditing. • HSE meetings. • Incident Investigation and Reporting. • Site security. • Medical care and first aid.

Furthermore, the Contractors shall develop and implement an emergency response plan outlining all necessary measures and communication procedures in case of emergency situations. The preparation and application of the HSE Plan shall be audited independently throughout the construction period. 5 Construction & Demolition Waste Management Plan 5.1 Waste Management General The Contractor shall be responsible for developing the Waste Management Plan related to its construction activities. The Plan shall apply to all works carried out by the Contractor and any subcontractors under their control. In preparing the plan, the Contractor shall take into account any measures set out any planning consent document, the relevant legislation, and industry best practice.

The Contractor shall comply with the objectives of the regional waste management plan and establish a system for the management of wastes in accordance with the waste management hierarchy:

• Prevention; • Minimisation; • Reuse; • Recycling, and; • Disposal.

Generally, the waste management goal will be achieved as follows:

• Giving preference to the purchase of materials with minimum packaging; • Storing materials in designated areas and separate from wastes to minimise damage; • Returning packaging to the producer where possible; • Reusing rock/soil on-site during the construction of the project; • Reusing and recycling materials on site during construction where practicable; • Recycling other recyclable materials through appropriately permitted / licences contractors

and facilities; • Disposing of only non-recyclable wastes to licensed landfills.

5.2 Wastes Arising & Management Construction works will be carried out according to best practice with standard environmental controls (see CIRIA 2010). Furthermore, all wastes generated during construction works will be transported off the site by licensed contractors following appropriate classification/segregation. These subcontractors will be identified nearer the commencement of construction. The Site Manager will ensure that the permits / authorisations held by each specialist subcontractor used have the necessary permits in place


for each waste type being managed. Cork County Council Environment Section will be consulted to confirm all permits are in order.

During construction, waste containers will be provided and rotated as soon as they are filled. A number of skips (20m3 typical) will be kept in a secure area adjacent the site compound. Wastes will be sorted and disposed of as per waste type to a nearby recycling / treatment facilities. Excavated material (soil and stone — EWC Code 17 05 04) will be re-used in full on site; it is not expected to be taken off site for recovery. Any excavated material stockpiled on site during construction will be stored in such a manner as to ensure no silt or run-off from these stockpiles enters any watercourse. In order to prevent any damaging run-off from the site, that there will be no stockpiling of soil within 10 m of a watercourse and silt fence/screens are utilised where deemed necessary. This is a standard working practice. The landscape work is to be implemented in tandem with the main building works where possible, further reducing run off to any watercourse onsite. As the site is a green field site, it unlikely that unsuitable material will be discovered during excavation, however if discovered, it will be stored separately and will be carted off site to designated dumping areas, by licenced contractors. This will be done in accordance with the “Waste Management Acts 1996-2008.” All excavations will be undertaken in accordance with Building Regulations and Health and Safety standards. The waste arising likely to be generated during the construction phase are:

• EWC 17 02 01 - Wood • EWC 17 02 03 - Plastic • EWC 17 04 05 - Iron & Steel • EWC 15 01 01 - Paper & Cardboard packaging • EWC 15 01 06 - Mixed Waste

In relation to foul waste arising from temporary toilet and canteen facilities the contractor will provide temporary storage facilities in the form of a prefabricated tank. The waste from the site toilet facilities will be removed from the site on a regular basis. Waste generated will be for the duration of the construction period only and there will be no requirement for either potable water or waste water treatment once the solar farm is operational. 5.3 Documentation of Waste The Contractor shall develop a Waste Documentation System within the overall documentation system for the works. The documentation to be maintained in relation to wastes includes the following (where applicable):

• The names of the agent(s) and the transporter(s) of the wastes; • The name(s) of the person(s) responsible for the ultimate recovery or disposal of the wastes; • The ultimate destination(s) of the wastes; • Written confirmation of the acceptance and recovery or disposal of any hazardous waste • consignments; • The tonnages and European Waste Catalogue (EWC) Code for the waste materials; • All other statutory recording requirements.


5.4 Hazardous Material It is not anticipated that there will be any need for hazardous waste on-site, however if required, the management of hazardous waste will comply with current legislation:

• The Waste Management Acts (WMA) 1996 to 2005 • Waste Management Regulations 1998;

Hazardous waste which may be produced or encountered on site includes:

• Soils contaminated with waste oils or fuels; • Waste oils and fuels;

6 Environmental Management 6.1 Existing Ecology The following mitigation measures will be implemented as part of the proposed project in order to minimise the potential impacts on the existing ecology, including:

▪ No removal of habitats or movement of construction machinery will occur outside of the development works area/footprint during the construction phase, where the works area/footprint will be clearly marked for associated site staff;

▪ Construction works will proceed with adherence to measures set out in CIRIA’s ‘Control of Water Pollution From Construction Sites’ (CIRIA 2001);

▪ The landscaping plan for the proposed development will be implemented. Only native tree and shrub species suited to the locality will be used in the final landscaping plan;

▪ In the event that protected fauna are found actively using the site for breeding/roosting (e.g. badger sett, bird nest, bat roosting) during the construction phase, works will cease immediately, and the area will be cordoned off until advice is sought from a suitably qualified/experienced ecologist.

▪ Mammal access through the development site will be facilitated by a 200mm high void at the base of the fence.

▪ All environmental protection measures including key component parts of the temporary construction compound will be agreed with Cork County Council’s Environment Department prior to commencement of development.

6.2 Soil Structure Protection To minimise damage to the soil structure within the solar farm site, the construction stage will typically be confined to a 55 week period of suitable weather conditions, with the use of appropriate machinery for such circumstances. Equipment will be delivered to site by heavy goods vehicles, and offloaded in packs by tracked machines or low ground pressure machines, which reduces the risk of compaction. The constructed access tracks which extend to all areas of the site will be the principal means to navigate the site for construction purposes. A delivery sequence of lower pressure vehicles will be devised which minimises repeated journeys over the pasture to reduce rutting and damage to the pasture and soil structure. Temporary ground-protecting access matting will be used in the area of the construction compound, as necessary. On completion of the works, the pasture will be restored using light farming machines and prepared appropriately for seeding to encourage early growth, restoration of the soil structure and natural creation of meadow grass.


Figure 11– Typical Low Ground Pressure Screw Pile Vehicle

6.3 Material Excavation and re-use on site The access track for the inverter/ transformer stations will require the preparation of a heavy-duty track made of compacted layers of material. To this effect, the soil will be stripped to a depth of about 200mm in order to remove the soft top soil and replaced by a layer of coarse gravel/ suitable substrate. This will be undertaken in accordance with agreed practices, with a disaggregated temporary storage area for the appropriate management of same will be set out within the construction compound.

Figure 12 – Typical Access Track Detail

The soil stripping works to facilitate the track excavations will extend to c.2,002 m3 of soil removal. All of this will be reused on site. The excavated material will be used directly to fill-in the verges of the internal track once the installation process is complete in accordance with proposed landscaping mitigation measures, with the residual re-tilled in the area of the temporary construction compounds to allow for full and active reinstatement for agricultural use.

Separately, and under the substation/grid connection application to An Bord Pleanála, it is the intention of the applicant to retain excavated material arising from the substation works on site to form berms across the wider solar farm site. The measures set out in Section 5 of the enclosed Lysaghtstown 110kV Substation Construction Methodology will be adhered to as part of these works.


6.4 Construction of Access Tracks There will be a requirement to import aggregate for the construction of the access track in the development site. This will be kept to a minimum. The quantity will be determined accurately at construction stage and will largely depend on existing ground conditions. Typical construction details are as per Figure 12. 6.5 On-Site Surface water generation and drainage The proposed development is designed so as to minimise effect on the original drainage and infiltration pattern of the site. The only surfaces where infiltration will be materially impeded are the substation, inverter/transformer and the battery storage units which extend to a cumulative area of approximately 749 m2 or 0.13% of the total site area. A detailed substation drainage report undertaken by Terra Solar, accompanies this application, with a separate drainage strategy for the solar array prepared by CSEA Engineering Advisors. Any existing drainage or ditch network shall be cleaned during construction and maintained on an annual basis by the site owner as per contractual obligation. It will therefore be ensured that the site drainage will constantly be optimal. It should be noted, that although PV panels may appear as a roof-like structure they do not prevent water from reaching the ground. The grass and original pasture quickly returns to its original state as shown in Figure 13. In fact, grass growth management does not differ from a normal pasture and will allow for sheep grazing. Any soil compaction that may occur during frame and panel installation will be chisel ploughed post construction to ensure there is no formation of rivulets.

Figure 13 – No effect on grass management or drainage requirement


6.6 Substation and Associated Earthworks 6.6.1 Excavation and Fill Works The existing site profile for the area of the proposed substation contains a gradual slope where the contour varies from 92m OD (north) to 86m OD (south). An Eirgrid compound level of 89.250m OD and a customer compound level of 86.250m OD will be established. Thus there will be a requirement to relocate up to 22,000m3 of soil to facilitate construction. It is proposed to retain excavated material on site to form berms around the substation compound and wider solar farm site which will provide screening and biodiversity benefits. Site investigations were undertaken by Malachy Walsh and Partners at the proposed substation location on 20th November 2020. These investigations show that excavated material will not be suitable to use as fill for construction of the compound. It is necessary to form berms in appropriate locations around the substation and wider permitted solar farm site to accommodate the excess material. These berms can be formed without any amendments to the permitted solar farm. Formations will be kept a minimum of 2.5 metres from permitted solar farm infrastructure. All proposed berms are set back a minimum of 5m from field drains and 10m back from small flowing watercourses. Classification of excavated soils will be confirmed by testing in accordance with the requirements of “Specification for Road Works Series 600 – Earthworks” prior to placement of materials. Berms will be formed at the locations shown on Macro Works Drawing LD.LYSGHTWN.SBSTN 1.1 as submitted with the SID application. The slope angle of earth berms constructed from Class 4 should be at an angle of 1V:3H (18.4˚). Steeper angles of 1V:2H (26.5˚) may be used for material that is classified as a Class 2 A/B/C/D. If necessary, geosynthetic reinforcement could be installed in berms to allow for installation to side slope angles of 1V:1H (45˚). 6.6.2 Landscaping When berms are formed, they will be topped with topsoil and planted with native wildflower/wildgrass seeding mix. A buffer of 5 metres will be maintained from field drains and a buffer of 10 metres will be maintained from flowing watercourses. The formation of berms will be subject to the following methods and work practices:

• Once formed, berms will be well tamped down, rolled and reseeded immediately.

• All berms will be planted with a wildflower/wildgrass seeding mix as soon as formation is complete. Hydroseeding will be implemented to quickly establish grass growth.

• Once seeded, berms will be surrounded by secure silt fencing until grassing over occurs.

• Earthworks and berm formation will take place in periods of dry weather.

• Machinery working on the berm construction near drains and watercourses will work from

the landside or on top of the berm, not on the side adjacent to drains or watercourses.


6.6.3 Sediment Control A comprehensive audit of the existing drainage network on the overall site will be carried out prior to works commencing, to clearly identify and mark the presence of drainage features including any permanent springs and active (flowing) channels within the site. This mapping will establish where flow originates (springs) and which channels are actively flowing. The purpose of this measure is to (i) avoid direct physical disturbance on these channels that can contribute to sediment loss, and; (ii) ensure that onsite sediment control measures are correctly located and implemented effectively in relation to their location. Any spring risings should be identified as part of these audits using OSI 6-inch mapping as guidance. No berms will be located on top of or within the flow path of any such springs. Freshly excavated spoil will be retained in an area over 5m away from any inactive drain or 10m from an active drain or watercourse (i.e., spring(s); active drains; small tributary). The spoil heap will be located on either a well vegetated area surrounded by silt fencing or with the use of containment measures (geotextile mat or bag) and covered to reduce potential for sediment export. A ready supply of these materials will be on site at all times to deal with these eventualities. 7 Noise Management It is expected that construction hours of operation will be between 08:00 and 18:00 Monday to Friday, and 08:00 and 16:00 on Saturday. No construction activities will occur outside these hours unless agreed in writing with Cork County Council. All plant will be required to conform to the construction noise code of practice BS 5225 and will be properly maintained by contractors. Solar PV panels do not generate any noise as there are no moving parts. Noise emissions arising from the operation of a solar farm are therefore limited principally to the inverters and transformers, which have a very low-level hum. The inverters/transformers are housed in noise insulating prefabricated structures where noise will be imperceptible. The typical acoustic volumes of such devices excluding incorporated structure/building insulation measures are:

• Acoustic Level of transformers: 58 dBA • Acoustic Level of inverters: 33 dBA

As a comparison, a modern dishwasher emits between 38 and 48 dBA. When insulated building conditions are applied, actual audible noise levels will be well below this and imperceptible from a few feet away. As outlined in the Planning and Environmental Statement, established precedent acknowledges that solar farms do not give rise to noise pollutant impacts. 8 Air Quality Dust can be created from movement of construction traffic and from general construction activities and can be carried by prevailing winds impacting upon the local area. The air quality management objectives are:

• Protection of air quality • Use all reasonable and practicable measures to minimise airborne dust and greenhouse gas

emissions to minimise impacts on land, flora/fauna, water and air quality • Track and report


• Minimise impacts on adjacent residents, land owners and community Construction traffic carrying loose material will be covered to reduce dust generation. This measure will be combined with wheel washing at site access points. A water bowser will be provided for dust suppression on site if necessary and areas of concern can be ‘dampened down’ during periods of dry weather. If necessary, arrangements will be made for sweeping public roads in the vicinity of the site access using a standard road sweeper. The Site Manager will be responsible for determining if additional measures will be required. 9 Archaeology The Archaeological, Architectural and Cultural Heritage Impact Assessment undertaken for the project includes a suite of construction management measures devised as part of a considered mitigation strategy. Identified measures, including the capacity for preservation in situ by design, and any actions arising from associated findings will be integrated into the final Construction Environmental Management Plan. The implementation of all required measures will be carried out under the full supervision of a suitably qualified archaeologist under licence from the state. In the event that previously unknown archaeological material is identified at the site then preservation in situ will be the preferred option. Preservation by record (through archaeological excavation) will only occur if it is established that preservation in situ cannot be achieved. The prepared archaeological report details a suite of construction mitigation measures, which will be rolled out during the construction phase. These include the use of tracked/low pressure machines to reduce risk of compaction and the completion of site restoration works using light farming machines. The specified buffer zonings to features of archaeological potential will be physically demarcated on the ground and adhered to, with focused monitoring by a suitably qualified archaeologist under licence also provided for. Refer to Section 5 of the archaeological report submitted with this application. 10 Reinstatement of Excavated Material after Construction Stage Reinstatement of all excavated materials will occur as close to the site of excavation as possible. Materials will be reinstated on site in restoration and landscaping works. Where practical, reinstatement and restoration of, and around the infrastructure will be carried out during the construction phase, or as soon as is practical after the completion of the works themselves. Early reinstatement and restoration is required to minimise visual impact and temporary storage/stockpiling of soils and to promote vegetation and habitat restoration as early as possible. Reinstatement involves placement of topsoil as required:

• On any areas of disturbed ground; • To exposed substrata areas as a result of the construction works; • Adjacent access tracks; • To construction compounds and other temporary works areas.

The Contractor is required to provide appropriate plant for undertaking reinstatement, restoration and landscaping works such that no unnecessary disturbance of the ground surface occurs. The Contractor’s plans and method statements will provide details on the timing and predicted extent of any necessary reinstatement, including the design and working methods for reinstatement and restoration of all of these elements.


11 Operational Site Management and Maintenance Once the construction phase is complete, an operations and maintenance plan will be put in place for the solar farm. Alongside system performance, this will include routine inspection and monitoring in relation to ongoing planning compliance requirements. This will include implementation of a habitat management plan and monitoring of ecology enhancements installed on the site to ensure their maintenance and improvement. The drainage regime on the site will be subject to regular inspection and cleaning/clearing as necessary. It is possible that sheep grazing will be the principal means of managing grass growth levels on the site which improves fertility of the soil under panels, while retaining the lands in productive agricultural use. This is consistent with best practice measures contained within the UK BRE Planning Guidelines for the development of ground mounted solar PV systems.

Figure 14 – Sheep Grazing (L) and Panel Washing with Water (R)

Panel cleaning will take place occasionally (approximately once per year) to remove bird droppings and pollen etc and maintain the operational efficiency of the solar farm. The panels will be cleaned by a tractor/trailer vehicle with a soft brush using demineralised water brought on site for this particular purposes. Detergents and any other chemicals will not be used as they can result in glass streaking reducing efficiency. 12 Decommissioning and Restoration The proposed development is temporary and will have an operational lifetime of 35 years. At the end of its operation all infrastructure will be decommissioned, dismantled and removed from the site. The Project consists of numerous recyclable materials, including glass, aluminium and silicon. When the Project reaches the end of its operational life, the component parts can be dismantled and recycled. The Project components will be dismantled and removed using minimal impact conventional construction equipment and be recycled or disposed of safely. Decommissioning of the site is estimated to take between 2 to 4 months in order to return the site for reuse as either pasture or arable land. Deconstruction will commence with removing the solar panels, followed by the mounting frames, then removal of the pile driven steel supports. This will be followed by the removal of the buried electrical cables, inverters, and pad foundations, of which there will be very few. CCTV system fencing and access tracks will then be removed to leave a clear field. The field will then be prepared for return to the landowner for agricultural use including the removal of the access track.


A decommissioning plan, which will be submitted to Cork County Council, will outline the required steps to remove the system, dispose of or recycle its components, and restore the land to its original state.

15

Appendix B Substation Drainage Report

Lysaghtstown 110kV Substation

Substation Drainage Report December 2020

Table of Contents

1. Introduction................................................................................................................................3

2. SurfaceWaterDrainage..............................................................................................................3

3. FoulSewerDrainage...................................................................................................................4

4. ProposedWaterSupply..............................................................................................................5

1. Introduction This document outlines the envisaged drainage scheme for a 110kV/33kV substation development in Lysaghtstown, Midleton, County Cork. The purpose of the proposed substation and grid connection is to serve a solar farm development in the townlands of Lysaghtstown, Ballyleary, Woodstock and Curragh, Co. Cork. The applications for planning permission for the solar panels, support infrastructure and associated ancillary development works were previously made to Cork County Council under permitted planning references 18/6769, 19/5729 and 19/6882.

Terra Solar II Limited are seeking a 10-year planning permission for development at Lysaghtstown, Co. Cork comprising a 110kV 4-bay C-type electricity substation (with 33kV customer compound) (including two control buildings, lightning protection, perimeter security fencing, security lighting, drainage infrastructure, temporary construction compound) to connect to and serve a solar farm; associated loop-in infrastructure to tie into an existing 110kV overhead transmission line including underground 110kV cabling and 2 No. new end masts with 110kV line diversion cabling; vehicular entrance and access track from public road; all associated site development works including formation of berms and landscaping. The proposed development of the 110kV / 33kV Electrical AIS substation will include two buildings to house electrical equipment and an electrical transformer bund within a fenced off compound with internal concrete roadways and the remaining area surfaced with permeable single size clean stone. There will be new private access tracks provided to the gates of the compounds – the IPP compound and Eirgrid compounds require separate accesses. The roof surfaces and the bunded plinths are the only areas within the compound that require drainage assessment. All other areas are free draining. The substation will be an unmanned facility in the operational phase, but will require welfare facilities for staff visiting the substation for inspections, routine maintenance and extraordinary maintenance as the need arises. These welfare facilities, which include toilets (WC), wash and basin (WHB) and sinks, will have a water demand and generate wastewater. 2. Surface Water Drainage Surface water drainage proposals for the proposed substation have been designed to mimic the natural drainage patterns of the site and thereby be in accordance with the Best Management Practices (BMPs) of Sustainable Drainage Systems (SuDS). This is easily achieved when the following parameters are considered:

• The compound construction is formed with permeable stone thus mimicking a soakaway scenario. ESB compound stone is single sized for the first 150mm for safety purposes. It then changes to a graded 6F2 material. The area of this permeable surface is circa 14,145m².

• The area to be drained includes the roofs and the bunded plinths. These equate to approximately 645m². These areas are modest in themselves and in comparison to the overall compound area.

• Assuming even the most basic of infiltration rates down through the permeable compound stone,

it is clear that the existing greenfield situation is easily maintained. The surface water generated in the bunded areas will discharge to the existing drainage via a Class 1 Full Retention Oil Separator. The electrical transformer in the substation is oil filled equipment and, as such, is protected with impermeable bunds. Surface water generated in this bund will be pumped out by an oil sensitive pump ensuring that only non-contaminated water enters the site drainage network. The substation will be constructed on a level platform, with an excess of excavated material. It is proposed to retain this excavated material on site to form berms around the substation compound and wider solar farm site which will provide screening and biodiversity benefits. These berms will be formed in a way that will maintain the free-draining nature of the site. This can be achieved during formation by allowing regular gaps in the berms to allow surface water to follow its natural path. A specialist hydrologist will be appointed during construction to oversee berm formation and ensure adequate surface water drainage is maintained. 3. Foul Sewer Drainage There are no existing foul sewer water drains on or near the proposed substation site. The dispersed settlement pattern of the surrounding area suggests that the individual farm dwellings use standalone private foul treatment and disposal systems. The foul drainage proposal must cater for the wastewater generated in the welfare facilities of the proposed substation. These welfare facilities include a toilet and wash hand basin in each of the two buildings. The stations will be unmanned in normal operation so demand for facilities which generate foul flows will be low. Onsite treatment and disposal of foul waste was considered by using a suitable septic tank and intermittent filter system and polishing unit or packaged wastewater treatment system and polishing unit. This will be subject to the results of the site characteristic testing as part of detailed pre-construction site investigations. However, the low volumes of foul waste that will be generated and consequently the low biological loading may impact on the successful continual operation of a treatment system reliant on bacterial action. For this reason, the alternative of a foul holding tank to be emptied periodically is proposed. Foul holding tanks are normally used in Eirgrid and ESB substations. The foul drainage proposed will have a capacity of 5m3 which is a multiple of the foul water generated over three months of normal operation of the station. The foul holding tank will also be inspected by a suitably qualified and indemnified person at these intervals and records of inspections will be held on site for inspection by the local authority. A freeboard of 300mm will be provided for and the foul holding tank will be fitted with a high-level alarm. This alarm will be connected to a manned control station via the

substation’s Supervisory Control and Data Acquisition (SCADA) telecom relay system. This will allow for non-scheduled maintenance and emptying of the tank between the regular three monthly intervals in the very unlikely event that this is required. The foul holding tank will also be vented to the atmosphere to avoid the buildup of noxious and dangerous gases. The proposed station will be unmanned and as such will generate small quantities of foul waste. There will be visits to the station for scheduled and unscheduled inspections, maintenance and repairs as necessary. It is anticipated that this will result in a contribution of 60 litres of foul waste per week. In the very unlikely event that such a high visitation rate would be extrapolated throughout the year, this would result in 6,323 litres per annum. While such a consistently high visitation is improbable, there is the possibility of increased numbers of staff being present on site for short durations during the commissioning of electrical elements of the station from time to time. It is envisaged that these extraordinary occurrences would balance out with the ordinary operation of the unmanned station to produce foul flows no greater than the 6,323 litres per annum as a “worst-case” scenario. It is common for much lower usage of the facilities on unmanned stations and therefore a much lower foul loading. A common problem on such unmanned stations is odours in the toilet areas due to the drying out of the water trap in the WC through evaporation resulting from the lack of use. For this reason, it is proposed to use self-flushing toilets in the station, which would flush automatically twice a week. The station will include two 6 litre flush WCs so a minimum weekly foul flow of 24 litres can be expected. The self-flushing WCs will therefore contribute 1,248 litres per annum. Combining the automatic flush and maximum user demand figures would result in a maximum annual generation of 7,571 litres (7.5m³) of foul sewer water waste. The 5m³ tank proposed will be emptied approximately every three months. As outlined, the capacity provided is well in excess of what is required. 4. Proposed Water Supply There is currently no water within the site of the proposed substation. If it is not feasible to connect to the public water supply system, it is proposed to provide the required potable water demand of the station with a bored well on site. The potable water demand within the site will be low as the proposed station is to be unmanned. To avoid issues like stagnation in the water supply line and problems resulting from this, there will be a continual water demand of 24 litres per week from automatically flushing WCs within the station. The water demand within the proposed development will be low and will be similar to the figures for foul sewer water generation as set out above in this report.

16

Appendix C Ground Investigation Report by Malachy Walsh and Partners

Malachy Walsh and Partners Engineering and Environmental Consultants

Cork | Tralee | Limerick | London

Ground Investigation Report

Lysaghtstown Substation

Project No.: 21574 Document No.: 6001 Rev: A Date: November 2020

Ground Investigation Report Lysaghtstown Substation Document No. 21574/6001/Rev. A ____________________________________________________________________________________________

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i November 2020

Contents 1 Introduction ......................................................................................................................... 1

1.1 Proposed Project and Purpose of Report .................................................................. 1 1.2 Desk Study ................................................................................................................ 1 1.3 Historical Mapping ..................................................................................................... 1 1.4 Topography ................................................................................................................ 3 1.5 Geology ..................................................................................................................... 3

1.5.1 Solid Geology ........................................................................................................ 3 1.5.2 Quarternary Geology ............................................................................................. 4 1.5.3 Hydrogeology/ Hydrology and Drainage ................................................................ 6

2 Site Walkover ..................................................................................................................... 8 2.1 Observations .............................................................................................................. 8

3 Factual Ground Investigation Reports ................................................................................ 9 3.1 Previous SI/Reports ................................................................................................... 9 3.2 Latest Ground Investigation ....................................................................................... 9

4 Ground Conditions ............................................................................................................. 9 5 Groundwater ....................................................................................................................... 9 6 Preliminary Engineering Assessment .............................................................................. 12 7 References ....................................................................................................................... 13

Appendices Appendix A – Site Layout Plan Appendix B – Site Walkover Photos

Project No.

Doc. No.

Rev. Date Prepared By Checked By

Approved By

Status

21574 6001 A 27.11.2020 JS PC PC Interim Draft Report

Malachy Walsh and Partners, Engineering and Environmental Consultants Address: Park House, Mahon Technology Park, Bessboro Road, Blackrock, Cork

Ground Investigation Report Lysaghtstown Substation Document No. 21574/6001/Rev. A __________________________________________________________________________________________

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1 November 2020

1 Introduction

1.1 Proposed Project and Purpose of Report

A substation building and compound is proposed in the townland of Lysaghtstown, Co. Cork. This report provides a desk study of the geology of the site, gives a description of the ground conditions encountered in trial pits completed at the site on 27th November 2020 and provides a preliminary engineering assessment of the ground conditions encountered. 1.2 Desk Study

A desk study was undertaken to collate and review available information, datasets and documentation sources pertaining to the site’s natural environment. The desk study involved the following:

Examination of maps and aerial photography; Examination of the Geological Survey of Ireland (GSI) datasets pertaining to geological

(bedrock, heritage, subsoil, aquifer) and extractive industry data; Examination of EPA / Teagasc online soil and subsoil maps;

1.3 Historical Mapping

A historic flood plain was also recorded on the Cassini 6 inch map approximately 3.6km east of the site, which is associated with a historic gravel pit. A second historic gravel pit approximately 0.5km west of the site. Several historic water springs and wells have also been recorded in the local vicinity.

Figure 1-1: Cassini 6 inch mapping overlain on aerial imagery and historic features (Geohive).

Site Location

Historic Gravel Pit

Historic Gravel Pit


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2 November 2020

Figure 1-2: Historic mapping (1837-1842) 6 inch cover (Geohive)

Figure 1-3: Lysaghtstown Aerial Image 2000 (Geohive)


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3 November 2020

Figure 1-4: Lysaghtstown Aerial Image Premium 2018 (Geohive) 1.4 Topography

The site is described as generally flat, sloping gently to the south-southeast. Average elevations of the site are circa 85-90 m AOD. 1.5 Geology

The online maps provided on the Geological Survey of Ireland (GSI) website were consulted to identify the anticipated ground conditions at the site.

1.5.1 Solid Geology

The GSI 1:100,000 scale bedrock geology map, Figure 1-5, shows that the site is underlain by the Gyleen Formation which has a maximum thickness of 463m. The Old Head Sandstone Fomations is present to the south, with a maximum thickness of 1098m. Two sets of faults, which intersect one another, have been identified by GSI maps. The first trends sotuhwest to northeast and the second trends north-northwest to south-southest. A section of the local geology can be seen on Figure 1-5. Pockets of bedrock outcrops were recorded south of the site. The GSI does not have any records for karst features within or near to the site. The closest recorded GSI karst feature is a turlough approximately 1.5km to the southwest of the site and a cave approximately 2.1km to the southeast of the site. The rocks found within and immediately adjacent to the site are described from literature below with the symbol for each formation given in brackets for cross-reference purposes with the bedrock geology map.

Gyleen Fomation (DUGYLE). These Upper Devonian rocks are described as Red

siltstone and subsidiary sandstone. The maximum thickness has been noted as

463m. The sequence is siltstone dominant (68%) but with a marked sandstone


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4 November 2020

content (32%). The base is marked by the lowermost erosive thick (greater than

1.5m) medium to coarse-grained sandstone. The formation is characterised by fining

upwards sequences. Fining upwards sequences of subsidiary red sandstone and

dominant red sandstones with thinly bedded alternations of green and red

sandstones, siltstones and mudstones towards the top.

Old Head Sandstone Formation (DUOHSF). These Upper Devonian rocks are

described as Flaser-bedded sandstone & minor mudstone. Thicknesses of between

899 to 1098m have been reported. The formation is dominated by lithologies

belonging to the Heterolithic Facies (mainly flaser-bedded sandstones), wavy bedded

fine-grained sandstones and minor mudstones. Grey flaser-bedded sandstones, fine

grained sandstones and minor mudstones and lenticular bedded mudstones.

Figure 1-5: Bedrock Geology 100k Map (GSI)

1.5.2 Quarternary Geology

The majority of the grid route is shown to be underlain by till derived from Devonian Sandstone. Alluvium is present at the east of the grid route. Bedrock outcrop is present to the south site. The GSI have no records of any landslides are recorded within the site. The closest recorded landslide events occurred over 10km away, northeast of the grid route just next to the shores of the Grand Canal. The bogslide occured in 1954 in raised peat near Derries Bridge on Pollagh Bog with no explanation of the landslide trigger given. There are no geological heritage sites located within the vicinity of the area. Mineral localities mapping showed an area about 0.5km west of the site on the GSI mapping. It is described as being a sand and gravel quarry. Geohive records two historic gravel pits in the local vicinity (Figure 1-1).


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5 November 2020

Figure 1-6: Teagasc Soil Map (GSI)

Figure 1-7: Quaternary Sediments (GSI)


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6 November 2020

1.5.3 Hydrogeology/ Hydrology and Drainage

The majority of the grid route is situated within a locally important aquifer which is described bedrock which is moderately productive only in local zones. Areas approximately 1km south of the site location is Regionally Important Aquifer - Karstified (diffuse) [Figure 1-8] Groundwater vulnerability was noted as “High” There are several groundwater borehole located in the vicinity of the site. The closest are located 1.6km west of the site, with an average depth of 25 mbgl and with an average yield of 44 m³/day (Figure 1-10). There are several hand pumps from the 1830s recorded surrounding close to the site. Geohive also records historic springs from the 1830s (Figure 1-1).

Figure 1-8: Groundwater Aquifers (GSI)


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7 November 2020

Figure 1-9: Groundwater Vulnerability (GSI)

Figure 1-10: Groundwater Wells and Springs (GSI)


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8 November 2020

2 Site Walkover

2.1 Observations

A site walkover and site investigations were completed on the 20th of November 2020. Photographs from the site walkover are given in Appendix B. The following observations were made:

Road conditions to the site location were good to poor in various places; The road changed from two lanes down to one lane hallway along the route; Water pooling was noted in the soils; Houses, access routes and farm buildings were found towards the site location;


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9 November 2020

3 Factual Ground Investigation Reports

3.1 Previous SI/Reports

No previous ground investigation information specific to this development is available. 3.2 Latest Ground Investigation

Intrusive ground investigation has been completed for this site by H&MV Engineering and MWP on the 20th November 2020. The ground investigation completed consisted of the following:

Six Trial Pits to a maximum depth of 2.20m BGL distributed along the proposed grid route;

4 Ground Conditions

Below is a short summary and commentary on the results of the ground investigation the site Table 1.

5 Groundwater

Groundwater strikes are noted on the exploratory hole summary in Table 1. One trial hole (TP02) was left open for 2 hours to check for ground water ingress and the strike was recorded at that time. Only slow to moderate seepage was noted, with very little water in the trial hole at the end of the 2 hour period. Note that the hydrogeological regime and groundwater levels would be expected to vary with the time of year, rainfall, nearby construction and other factors.


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10 November 2020

Table 1- Ground Conditions Summary Table

Trial

Pit No.

Topsoil

(depth

bgl)

Natural Ground (depth bgl) Water

encountere

d

Max depth encountered

Comments

TP01 0 – 0.35 m 0.35-1.50 m: Firm, red-brown slightly sandy, gravelly, silty

CLAY with occasional cobbles.

1.50-1.90 m: Stiff, red-brown slightly sandy, gravelly, clayey

SILT with occasional cobbles.

Yes (0.2 m) 1.90 m bgl Pit unstable at the top.

Clasts composed of subrounded to

subangular 5 – 100mm siltstone and

sandstone.

Water encountered at 0.2mbgl, water

ingress moderate.

Diggability of pit: easy to moderate.

TP02 0 – 0.30 m 0.30-1.30 m: Soft to firm, red-brown gravelly clayey SILT with

cobbles.

1.30-1.50 m: Firm, red-brown gravelly clayey SILT.

1.50-1.80 m: Stiff, red-brown gravelly clayey SILT.

1.50-1.80 m: Firm, red-brown very gravelly clayey SILT with

occasional cobbles.

1.80-2.20 m: Stiff, red-brown gravelly clayey SILT with

occasional cobbles.

Yes (2.20 m) 2.20 m bgl Gravel content increases with depth.

Diggability of pit: moderate.

Clasts composed crumbly, angular to

subrounded 2.5 – 100mm siltstone and

sandstone.

TP03 0 – 0.30 m 0.30-1.00 m: Firm, orange-red-brown very sandy gravelly with

occasional cobbles.

1.00-1.70 m: Firm, red-brown sandy very gravelly SILT with

occasional cobbles.

1.70-1.90 m: Firm to stiff, red-brown very gravelly SILT with

occasional cobbles.

No 1.50 m bgl Terminated due to possible bedrock at

1.90 m bgl.

Diggability of pit: easy

Clasts composed of angular to

subrounded 2.5 – 100mm siltstone and

sandstone.


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11 November 2020

TP04 0 – 0.30 m 0.30-1.00 m: Firm, dark red-orange-brown very silty very sandy

gravelly CLAY with occasional cobbles.

1.00-1.60 m: Stiff, red-brown slightly sandy silty gravelly CLAY

with occasional cobbles.

1.60-2.10 m: Soft-firm, red-brown slightly sandy silty gravelly

CLAY with occasional cobbles

No 2.10 m bgl Hand sample from 0.30-1.00 m was

darker and crumbly.

Clasts composed of subangular to

rounded 5 – 200mm siltstone and

sandstone.

Clast size decreases slightly with depth.

TP05 0 – 0.30 m 0.30-1.00 m: Firm-stiff, red-brown slightly gravelly clayey SILT

with occasional cobbles.

1.00-1.25 m: Firm-stiff, red-brown very sandy very gravelly

SILT with occasional cobbles.

1.25-1.40 m: Stiff, orange-red-brown very sandy silty GRAVEL.

No 1.40 m bgl Diggability of pit: easy to moderate

Terminated due to possible bedrock at

1.40 m bgl.


rounded 5 – 150mm siltstone and

sandstone.

TP06 0 – 0.30 m 0.30-1.00 m: Stiff, red-brown-grey slightly sandy very gravelly SILT with occasional cobbles. 1.00-1.50 m: Firm, orange-dark red- brown sandy gravelly SILT with occasional cobbles. 1.50-1.70 m: Firm, orange-red-brown very sandy very gravelly SILT with occasional cobbles.

No 1.70 m bgl Sand Fraction increases with depth.

Terminated due to possible bedrock at

1.70 m bgl.


subrounded 5 – 100mm siltstone and

sandstone.


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12 November 2020

6 Preliminary Engineering Assessment

The Glacial Till encountered below the topsoil (approximately 0.5m below ground level) onsite will provide a suitable formation layer for the compound and structures on this site. Plate load testing will be required at construction stage to prove the design bearing capacity is achieved. The reusability of material excavated from the substation site has been assessed based on TII document “Specification for Road Works Series 600 – Earthworks (CC-SPW-00600 March 2013)”. The following is noted:

All material encountered onsite can be classified for reuse in accordance with one or more of the classifications given in “Specification for Road Works Series 600 – Earthworks”

From the site investigations, the Glacial Till will be suitable for reuse as a Class 2

A/B/C/D (General Fill). This sub-classification of the Class 2 material is to be confirmed during construction phase of the project. Localised areas of more granular clay were encountered as noted on the trial pit summary tables, however, the clay content was still relatively high and unlikely to be low enough to consider the material as a Class 1 fill.

The Glacial Till excavated at this site is suitable for reuse as Class 4 (Fill to Landscape

Areas). Class 4 material is suitable for forming earth berms at the site.

The topsoil encountered onsite is suitable for reuse as a Class 5A (“Topsoil, or turf, existing onsite”).

The Subsoil encountered in the trial holes will be suitable for reuse as a Class 4 fill.

The Glacial Till encountered onsite will not meet the requirements for Class 6F or 6N

as the fines content is too high. Class 6F and 6N typically require the use of crushed rock to meet the specification. Import of quarried material from an external quarry will be required for construction of the substation compound. The material should be sourced from a quarry that is certified to provide Class 6F and 6N material that meets the requirements of SR21.

No class U material (unusable) material was encountered onsite. Classification of soils will be confirmed by testing in accordance with the requirements of “Specification for Road Works Series 600 – Earthworks” prior to placement of materials. The nature of the slopes across the site suggest that a cut and fill operation will be required to provide for a level platform. Permanent cuttings in Glacial Till at this site should be at an angle of 1V:2H or shallower. The fill within the compound should be a granular fill (eg Class 6). Fill under the buildings, transformers and other equipment should be SR21 compliant. Class 6 fill will not be won onsite and will require import form a suitably licenced quarry. The slope angle of earth berms constructed from Class 4 should be at an angle of 1V:3H (18.4 degrees). Steeper angles of 1V:2H (26.5 degrees) may be used for material that is classified as a Class 2 A/B/C/D. Geosynthetic reinforcement could be installed in berms to allow for installation to side slope angles of 1V:1H (45 degrees).


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13 November 2020

7 References

GSI Online Maps, Accessed 27/11/2020 Geohive Online Maps, Accessed 27/11/2020


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November 2020

Appendix A

Site Plan

A.J.

A.J.

A.J.

A.J.

A.J.

A.J.

H01

H02

H03

H04

H05

B

B

A

A

TP01X:584548.98Y:575625.57

TP02X:584571.69Y:575591.41

TP03X:584562.73Y:575561.39

TP04X:584591.54Y:575538.76

TP05X:584541.28Y:575521.63

TP06X:584522.29Y:575566.46

1. ALL DRAWINGS ARE TO BE READ IN CONJUNCTION WITH ALLRELEVANT SPECIFICATIONS, BILLS OF QUANTITIES,ARCHITECTURAL, SERVICES AND ENGINEERING DRAWINGS.

2. ALL LEVELS ARE IN METRES RELATED TO ORDNANCE DATUMMALIN HEAD.

3. ANY DISCREPANCIES BETWEEN THESE DOCUMENTS SHALL BEBROUGHT TO THE ATTENTION OF THE ENGINEER.

4. DRAWINGS ARE NOT TO BE SCALED.

5. ALL DIMENSIONS ARE IN MILLIMETRES, UNLESS NOTEDOTHERWISE.

NOTES:

DRAWINGNUMBER:

REV:

DRAWN: CHECKED:

DRAWINGSTATUS:

DO NOT SCALE FROM THIS DRAWING. USE FIGURED DIMENSIONS IN ALL CASES.VERIFY DIMENSIONS ON SITE AND REPORT ANY DISCREPANCIES TO THE

DESIGNERS IMMEDIATELY.THIS DRAWING TO BE READ IN CONJUNCTION WITH THE DESIGNERS

SPECIFICATION.© THIS DRAWING IS COPYRIGHT AND MAY ONLY BE REPRODUCED WITH THE

DESIGNERS PERMISSION.

PROJECTNUMBER:

Malachy Walsh and PartnersEngineering and Environmental Consultants

TITLE:

PROJECT:

CLIENT:

DATE: SCALE @ A1:

APPROVED:

N:\pr

ojects

\2157

4 - Ly

sagh

tstow

n\Dra

wing

s\Ske

tch\21

574-

MWP-

SK01

.dwg

REV DATE DESCRIPTION BY APP

Cork Tralee London Limerick

Reen Point,Blennerville,Tralee,Co. Kerry,V92 X2TK

Tel. : +353 (0) 66 7123404Fax. : +353 (0) 66 7126586E-mail : [email protected] : www.mwp.ie

21574

LYSAGHTSTOWN 110kV SUBSTATION

PROPOSED TRIAL HOLE LOCATIONS

21574-MWP-SK01

S2

P01

09.11.2020 1:500

NT PC JOL

ISSUED FOR INFORMATIONP01 09.11.2020 NT PC

Map Reproduced From Ordnance Survey IrelandBy Permission Of The Government.

Licence Number EN 0015720.

Proposed Trial Hole Locations Scale: 1:500

PROPOSED TRIAL HOLE LOCATIONS

LEGEND:

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Level

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EP

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Pylon

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NER

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TANK

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DIESEL GENERATOR

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HOUSE TRANSFORMER

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C2

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I.S. EN ISO 9001

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N

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S

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NE

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E

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W

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SW


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November 2020

Appendix B

Trial Pit Photographs


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November 2020

Trial Pit 1


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November 2020

Trial Pit 2


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November 2020

Trial Pit 3


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November 2020

Trial Pit 4


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November 2020

Trial Pit 5


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November 2020

Trial Pit 6

Lysaghtstown 110kV Substation Construction Methodology

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