York Potash - Preliminary Designplanning.northyorkmoors.org.uk/MVM.DMS/Planning...

York Potash Ltd

York Potash - Preliminary Design

Domestic Foul Drainage Disposal to Wilton - Feasibility Report

REP-P2-FD-003

Rev0 | 11 February 2015

This report takes into account the particular instructions and requirements of our client.

It is not intended for and should not be relied upon by any third party and no responsibility is undertaken to any third party. Job number 234376/41

Ove Arup & Partners Ltd Admiral House Rose Wharf 78 East Street Leeds LS9 8EE United Kingdom www.arup.com

York Potash Ltd York Potash - Preliminary DesignDomestic Foul Drainage Disposal to Wilton - Feasibility Report

REP-P2-FD-003 | Rev0 | 11 February 2015

J:\230000\234376-00\0 ARUP\0-12 WATER\0-12-08 REPORTS\01 DOMESTIC FOUL DRAINAGE\2015-02-11 DISPOSAL TO WILTON REV0\REP-P2-FD-003 FOUL DRAINAGE DISPOSAL TO WILTON FEASIBILITY 150211 REV0.DOCX

Contents

Page

1 Introduction and Guiding Principles 1

1.1 Introduction 1

1.2 Scope and objectives 1

1.3 Documents Referenced 2

1.4 Accompanying Drawings 2

1.5 Design Guidance 2

2 Consultation 3

3 Options Identification & Appraisal 3

3.1 Discharge of raw sewage vs treated sewage 3

4 Concept Design 4

4.1 Domestic Foul Sewage Flow Estimation 5

4.2 Package treatment plant 5

4.3 Pumped rising main 6

4.4 Sump / Storage tanks 7

4.5 Treatment at Wilton 7

5 Capital Cost Estimate 8

6 Summary and Conclusions 8

Appendices

Appendix A

Drawings

Appendix B

Capital Cost Estimate




Page 1

1 Introduction and Guiding Principles

1.1 Introduction

Arup has been engaged by York Potash Ltd (YPL) to provide assistance in preparation of a planning application for development of a polyhalite mine within the North York Moors National Park Authority (NYMNPA). The majority of above ground development is due to occur at the Dove’s Nest site and will primarily consists of mine-shafts with mine-head buildings, offices and welfare buildings.

As part of the proposed development, consideration needs to be given to the management of domestic foul sewage generated at the Dove’s Nest site during the construction and operational phases. During construction, the Contractor will be responsible for collecting domestic foul sewage and tankering it away from site for treatment. However during the operational phase, permanent domestic foul drainage infrastructure is required.

Arup has previously been engaged to evaluate the viability of providing an off-site connection to the Yorkshire Water public sewer to convey operational phase sewage. Due to proximity from the site and the requirement for substantial network upgrades, development of an on-site package treatment plant was found to be the more favourable option.

Through discussion with the Environment Agency, a number of concerns have been raised with the on-site treatment option, primarily relating to the potential adverse impact of discharging treated sewage effluent to the neighbouring Sneaton Thorpe Beck.

As part of the proposed development, non-domestic wastewater will be produced as a result of groundwater ingress into the mine, shafts and through the MTS tunnel walls. It is proposed that any groundwater ingress will be collected and pumped to Wilton where it will be treated. The EA has requested that YPL investigate the viability of using the same wastewater pumping system in the MTS tunnel to discharge domestic foul sewage from the Doves Nest site to Wilton, removing the risk of any impact to Sneaton Thorpe Beck.

This report has been prepared to further define this proposed solution and examine its viability. Factors considered in this assessment include health & safety, technical viability, sustainability and cost.

1.2 Scope and objectives The scope of this report is to evaluate the viability of discharging sewage (raw or treated) to Wilton for treatment and disposal. This option is evaluated against the existing base solution (as proposed in the current planning application) of discharging treated effluent to Sneaton Thorpe Beck. The scope of works addressed by this study include:

Further development and definition of the proposed solution




Page 2

Consideration of issues associated with transportation of raw sewage, partially treated and treated sewage effluent (septicity, odour, explosive gas risks)

Consideration of technical constraints associated with transport of sewage across 360m vertical drop from the welfare building at ground level to the start of the MTS tunnel at approximately 360m bgl, including pressure management in the vertical pipe stack and receiving tank (including energy dissipation measures).

Review design for the proposed non-domestic wastewater transportation system with consideration of the likely impact of additional flows on proposed pipe sizes, wet-well sizing and pumping configuration.

Examine the impact of increased flow and biological loading on the proposed treatment plant at Wilton with K Home International Ltd.

Consideration of the operational cost implications of increasing flows in the MTS pumped rising main

1.3 Documents Referenced

Document Ref Document Title

REP-P2-WSD-003 Rev 5

Integrated Water and Wastewater Management Strategy

REP-P2-FD-001 Rev1

Whole Life Assessment of Disposal Options for Domestic Foul Sewage from the Doves Nest site

REP-P2-FD-002 Rev1

On-site Treatment of Domestic Foul Sewage at Dove’s Nest

TN-P2-FD-001 Rev 0 Domestic Foul Sewage Effluent and Water Quality Impact – H1 Assessment

Table 1.1 Documents Referenced

1.4 Accompanying Drawings

Drawing Number Drawing Title

25900-MTS-CD0-2310-00010 Rev E

Tunnel Drainage – Horizontal Schematic Layout

Table 1.2: Accompanying Drawings

1.5 Design Guidance The following design guidance has been used

Document reference Document title

BS EN:12056 Gravity Drainage systems inside buildings: Part 2 Sanitary pipework, layout and calculation

British Water: Flows & Loads 4 - Sizing criteria, Treatment capacity for sewage treatment systems

Table 1.3: Design guidance document




Page 3

2 Consultation

As part of the planning application process, discussions have been held with NYMNPA and the Environment Agency to discuss proposals for the treatment and disposal of domestic foul sewage from the Doves Nest site.

The Environment Agency has previously requested that a Whole Life Assessment be undertaken to evaluate the viability of making an off-site connection vs on-site treatment considering sustainability, viability and practicality. In June 2014, a copy of this report was provided to the EA for evaluation. Following comments pertaining to the water quality assessment, this study was later supplemented by a revised H1 Assessment prepared in September 2014, demonstrating the impact of proposed treated effluent discharge on Sneaton Thorpe Beck.

Upon review of these documents, the EA has continued to express concern over the sensitivity of Sneaton Thorpe Beck to discharges from the on-site treatment plant, with particular concern expressed in regards the management of failures in the treatment process and the reduced dilution of residual ammonia which would occur during low flow conditions in the beck.

In reviewing the YPL planning submission, the EA has queried whether there may be an opportunity to utilise the proposed non-domestic wastewater pumped rising main (located within the proposed MTS tunnel) to convey sewage to the proposed treatment plant at Wilton. For the planning submission it was estimated that approx. 800m3/day will be pumped to Wilton for treatment. The proposed domestic sewage generation during peak the 13Mtpa operation phase is estimated at 70m3/day, representing less than 10% of the non-domestic wastewater volume.

This report has been prepared to help further discussions between YPL and the EA, helping confirm the viability of pursuing foul drainage discharge to Wilton.

3 Options Identification & Appraisal

3.1 Discharge of raw sewage vs treated sewage A high level assessment has been carried out to establish the merits of treating foul sewage generated at the Dove’s Nest site prior to onward pumping to Wilton. Partial treatment options (such as maceration of the sewage prior to transport) have also been considered.

It has been concluded that pumping raw untreated sewage (macerated or otherwise) to Wilton is not viable for the following reasons:

Health & Safety: Additional H&S risks associated with introducing raw sewage to a confined space. Risk of toxic and explosive gases (H2S, CH4) forming in the tunnel. Air valves will be required in the rising main providing a route for odour and gases to enter the tunnel. This can be avoided by treating the sewage on the surface prior to discharging ‘clean’ effluent.

Treatment process: The treatment process at Wilton is primarily aimed at treating chemical contamination arising from ground water ingress as part of the mining operation. Introduction of untreated raw sewage will require




Page 4

the treatment process at Wilton to be amended to accommodate a revised wastewater chemistry. Treatment of the sewage in advance of discharge to Wilton will result in an increased wastewater volume but will have little or no impact on the quality of wastewater arriving at Wilton.

Septicity: Pumping raw sewage along the 36.7km long pipeline introduces a higher risk of septicity in the pumped rising main. Yorkshire Water typically require retention times less than 12 hours before requiring septicity control. Chemical dosing would most likely be required to be applied to the full treated volume if pumping raw sewage to Wilton.

Corrosion: Use of the proposed rising main to convey raw sewage potentially increases corrosion risk along the pipeline, reducing its life span and increasing maintenance / repair costs.

Cost: Amending the treatment process at Wilton to accommodate foul sewage treatment is likely to result in a greater operational and capital works cost as the entire pumped volume must be treated to the required standard.

Based on the health and safety risks and technical issues identified above, it has been determined that pumping raw sewage to Wilton for treatment should be ruled out. On-site treatment using a package treatment plant with treated effluent pumped to Wilton is considered further in Section 4 of this report.

4 Concept Design

It is considered that treated sewage effluent generated at Dove’s Nest can be pumped to Wilton via the proposed rising main required for delivery of non-domestic wastewater and tunnel groundwater ingress.

Based on discussion in Section 3.1, this discharge will be treated using a package treatment plant prior to transportation to Wilton. This will reduce H&S risks, septicity issues and reduce impact on the treatment works at Wilton. It is proposed that treated effluent will be pumped from the welfare building to the portal of the men and materials drift tunnel from where it will gravitate to the -70m bgl level. From this point, sewage will gravitate in a vertical shaft to -360m bgl where it will be collected in a holding tank. It is proposed that non-domestic wastewater generated from the mining process also contribute to this tank. As part of the proposed non-domestic wastewater MTS transport system, a pumping station will be constructed in the base of the MTS shaft. The pumping station design will be revised to pump the combined treated sewage effluent / non-domestic wastewater mix to Lady Cross Plantation for onward pumping to Wilton.

A concept design for the new pumped rising main has been prepared as part of the planning application submission. Details of the proposed horizontal alignment are provided in drawing 25900-MTS-CD0-2310-00010 Rev E (Appendix A). Non-domestic wastewater is transported to Wilton through a combination of gravity drainage pipes and pumped rising mains. A description of the key components of the pipelines are provided in Table 4.2.

Upon arrival at Wilton, the treated sewage effluent / non-domestic wastewater mix will be treated. This is discussed further in Section 4.5.




Page 5

4.1 Domestic Foul Sewage Flow Estimation A previous study undertaken by Arup estimated the anticipated daily sewage flows generated by the proposed Miner’s Welfare building at the Dove’s Nest site based on published guidance produced by British Water for sizing wastewater treatment plants. In preparing these estimates, two operational scenarios were considered (6.5Mtpa & 13Mtpa). An extract from this study is presented in Table 4.1, indicating the anticipated foul sewage demands.

Worker assignment Time on

site (hrs)

Staff No.

6.5Mtpa

Staff No.

13Mtpa

Individual

usage

(l/per/day)

Total usage

6.5Mtpa

(l/day)

Total usage

13Mtpa

(l/day)

Mine Management 9:30 50 65 100 5,000 6,500

Office based 9:00 5 5 100 500 500

Days only 9:45 47 66 153 7,207 10,120

Production (Miners) 24:00 135 255 153 20,700 39,100

Infrastructure 24:00 38 66 153 5,827 10,120

Shaft workers 12:45 18 18 153 2,760 2,760

Security 24:00 4 4 100 400 400

Cleaners 4:00 2 2 50 100 100

Totals 299 481 42,493 69,600

Table 4.1 Domestic Foul Sewage Volume estimation

The domestic foul sewage infrastructure is required to accommodate the final development scenario (13Mtpa production) where up to 500 workers will be on site in any given 24hr period.

It is estimated that at peak operation, approximately 70m3/day of sewage will be generated. This represents an average flow rate of 0.8l/s. This sewage volume has been used as the basis for this assessment.

4.2 Package treatment plant The design of the proposed on-site package treatment plant has previously been developed by WPL Ltd based on anticipated sewer inflows. The previously specified plant is considered suitable to produce a treated effluent quality which will pose minimal risk to health, risk of explosive gases forming or impact on the treatment process at Wilton.




Page 6

Sewage effluent will be treated using the previously proposed HiPAF package treatment plant supplied by WPL Ltd. Details of the proposed treatment plant components are provided in REP-P2-FD-002 Rev1. The treatment works consists of a header tank, primary settlement tank, 2No. Biozones, Humus tank and Rapid Sand Filter.

4.3 Pumped rising main The proposed HiPAF package treatment plant is to be located adjacent to the welfare building, located in the lowest part of the site. In order to get treated effluent into the MTS tunnel, there will be a requirement to construct a small pumping station to pump effluent to the entrance portal of the men and materials drift tunnel from where it will gravitate to the base of the MTS shaft. The horizontal alignment of the proposed pumped system is provided in YP-P2-SK-015 (Appendix A).

Consideration needs to be given through design development to controlling velocities in these steep sections of pipe to ensure that excessive thrust is not exerted on pipe joints and that tanks are designed with suitable energy dissipation provisions.

From the base of the MTS shaft, it is proposed to utilise the non-domestic wastewater pipework in the MTS tunnel to convey water to Wilton. Details of the rising main proposed is provided in Table 4.2.

Location Pipe Flow (l/s)

Pipe length

(m)

Pipe Diameter

(mm)

Doves Nest to Lady Cross

1.7 8,000 80

Lady Cross to High point 6.7 8,000 100

Gravity from High point to Lockwood Beck

21.7 7,700 225

Lockwood Beck to Tocketts Lythe

32.7 5,600 200

Tocketts Lythe to Wilton 36.7 7,300 250

Total - 36,600 -

Table 4.2 Pumped rising main in MTS tunnel (excluding treated sewage effluent)

It can be seen that the discharge in the rising main increases incrementally moving along the tunnel length, reflecting the increasing drainage catchment on approach to Wilton. It is estimated that during the operational phase a daily volume of approximately 959m3 (500m3 from groundwater ingress, 459m3 from non-domestic wastewater) will be pumped to Wilton for treatment under the current design solution.

Introducing additional treated sewage effluent at Doves Nest will result in additional energy being required to pump the flow and increased headlosses in the pipe network itself. Increases in headloss may result in a requirement to use larger pumps and increased operational cost. It is estimated that increasing flows by 70m3/day results in an increase in power consumption of approximately 8% per




Page 7

year, corresponding to an extra £8.5k per year energy cost (based on electricity price of 17p/kWhr).

Alternatively, headloss in the system can be maintained by upsizing the pipe lengths as required to deliver an equivalent pumping head. Although the design of any pipework in the MTS tunnel will be the responsibility of the successful D&B contractor, estimates of the revised pipe sizes based on pumping an additional 70m3/day are provided in Table 4.3.

Location Pipe Flow (l/s)

Pipe length

(m)

Pipe Diameter

(mm)

Doves Nest to Lady Cross 2.5 8,000 100

Lady Cross to High point 7.5 8,000 100

Gravity from High point to Lockwood Beck

22.5 7,700 225

Lockwood Beck to Tocketts Lythe

33.5 5,600 250

Tocketts Lythe to Wilton 37.5 7,300 250

Total - 36,600 -

Table 4.3 Revised rising main sizing in MTS tunnel (including treated sewage effluent)

Based on the revised pipe sizes proposed in Table 4.3, the overall headloss across the system will remain broadly similar to that currently proposed, resulting in a small increase in capital cost, but a minimal increase in operational costs.

4.4 Sump / Storage tanks As discussed in Section 4.3, due to the presence of large vertical drops along the proposed pipe network, suitable energy dissipation will need to be incorporated into the design of these pipes to ensure velocities are controlled within an acceptable range.

Thrust restraints may however still be required at bends and changes in direction along the length of the pipe. Energy dissipation may also be required in any holding tank located within the base of the MTS shaft. Consideration should also be given to the potential for the vertical pipe to become fully charged with water and any resulting issues with pressure management.

4.5 Treatment at Wilton Discussions have been held with K Home Ltd to establish the likely impact of increasing pass forward flows to the proposed treatment works at Wilton.

K Home Ltd has advised that treatment of an additional 70m3 of water is not likely to cause technical difficulties. Based on the proposed chemistry and residual biological load of the treated sewage effluent, it is considered likely that this additional load can be easily accommodated within the proposed treatment process. On this basis the option is considered technically viable.




Page 8

5 Capital Cost Estimate

A budget cost estimate has been prepared as part of this study to estimate the capital cost of constructing additional infrastructure associated with discharging treated foul effluent to Wilton via the MTS tunnel. Arup has sought input from Gardiner & Theobald in developing this cost estimate.

It is noted that the costs of on-site treatment at Dove’s Nest Farm and any increased cost for construction of the wastewater treatment plant at Wilton have been excluded from this assessment.

It is estimated that the additional capital infrastructure required will cost approximately £700k. Details of the key assumptions and exclusions are provided in Appendix B.

6 Summary and Conclusions

The EA has requested that consideration be given to discharging domestic foul sewage generated at the Doves Nest site during the operational phase via the proposed non-domestic wastewater rising main to be incorporated in the MTS tunnel. This study has been undertaken to review the viability of implementing this solution, seeking to further define the key issues and identify the implications of adopting this solution.

For a number of reasons (including health & safety, septicity and cost), options which involve passing untreated raw sewage to Wilton has been discounted in favour of adopting an on-site treatment process and pumping the treated sewage effluent to Wilton. This approach provides better control over the effluent quality and reduces impact on the proposed treatment process at Wilton.

Discussions with designers of the non-domestic wastewater treatment plant at Wilton (K Home Ltd) have been consulted and confirmed that addition of 70m3/day of treated effluent will not impact significantly on their treatment process and is acceptable.

The proposed pumped rising main network has been evaluated to determine if the addition of 70m3/day has a negative impact on the performance of the system. It has been estimated that increasing flows in the pipe network results in an increased energy costs of approximately 8%. Over this lifetime of the mining operation, this would increase pumping costs by approximately £8.5k per year (based on current electricity prices). In addition, all pumps proposed would need to be upsized to accommodate the additional pumping head.

As a mitigation against these changes, calculations have been undertaken to determine the revised pipe sizes required to achieve a similar headloss situation resulting in minimal net increase in energy demand (see Table 4.3).

Based on the investigations undertaken, it is concluded that discharge of treated sewage effluent to Wilton via the MTS tunnel offers a technically viable solution, eliminating the risk of a deterioration in water quality in Sneaton Thorpe Beck. The additional infrastructure required to convey treated sewage effluent to and along the MTS tunnel would result in an increased capital cost of approximately £700k and a small increase in energy consumption and operating cost.




Page 9

Residual issues to be addressed by the designer / operator will primarily revolve around managing high velocity flows in the vertical shafts and ensuring the continued Health & Safety of operatives working in the tunnel.

Appendix A

Drawings

Vertical drop from approx-70m bgl to -360m bgl. Energydissipation required in pipe

Gravity sewer conveyingwater from pumped outfallto vertical shaft

Proposed pumping stationand pumped rising main toconvey water from packagetreatment plant to entranceportal of drift tunnel

Proposed alignment ofpumped rising main fromWwTW to men & materialsdrift tunnel portal

Indicative alignment ofproposed pumped risingmain within MTS tunneldischarging to Wilton

Proposed pumped station

Proposed gravity seweralong men and materials drifttunnel

Storage tank to be provided atbase of MTS shaft totemporarily store treatedsewage effluent at head ofrising main to Wilton

Wilton

3

6

.6

0

4

,6

7

K

m

3

6

.0

0

0

K

m

3

5

.0

0

0

K

m

34.000 K

m

33.000 K

m

32.000 K

m

31

.0

00

K

m

30.000 K

m

29.000 K

m

28.000 K

m

27.000 K

m

O

V

E

R

L

A

P

OV

ER

LA

P

C

hainage 29.379,00 K

m

E = 462954.980

N = 517350.503

Tocketts Lythe

E = 458154.321

N = 522678.880

Lined tunnel section

Discharge point

Pumping Station

150m

m

Ø

G

ravity P

ipe

Pum

pin

g M

ain

250mm Ø

300mm Ø

Gra

vity

Pip

e

4

4

P

um

pin

g M

ain

200m

m

Ø

5

5

MH/ Inspectio

n

Chamber

Sump pump

P

u

m

p

in

g

M

a

in

2

5

0

m

m

Ø

C

h

a

in

a

g

e

27.000 K

m

26.000 K

m

25.000 K

m

23.000 K

m

22.000 K

m

21.000 K

m

20.000 K

m

19.000 K

m

18.000 K

m

1

7

.0

0

0

K

m

1

6

.0

0

0

K

m

1

5

.0

0

0

K

m

1

4

.0

0

0

K

m

1

3

.0

0

0

K

m

24.000 K

m

O

V

E

R

L

A

P

OV

ER

LA

P

OV

ER

LA

P

O

V

E

R

L

A

P

Chainage 23.862,30 K

m

E = 467438.488

N = 514136.128

Lockwood Beck &

Stanghow Hall Farms

Pumping Station sump

MH

/ In

spection

Cham

ber

2

2

5

m

m

Ø

G

ra

v

ity

P

ip

e

P

u

m

p

in

g

M

a

in

1

0

0

m

m

Ø

T

B

M

In

te

rfa

c

e

H

ig

h

P

o

in

t in

T

u

n

n

e

l

225mm Ø

Gra

vity Pip

e

150mm Ø

Gra

vity

Pip

e

Pum

pin

g M

ain

200mm Ø

2

2

4

4

3

3

13.000 K

m

12.000 K

m

11.000 K

m

10.000 K

m

9.000 K

m

8.000 K

m

7.000 K

m

6.000 K

m

5.000 K

m

4.000 K

m

3.000 K

m

2.000 K

m

1.000 K

m

0

.0

0

0

K

m

OV

ER

LA

P

O

V

E

R

L

A

P

Chainage 8.122.85 K

m

E = 481577.056

N = 507575.994

Lady Cross Plantation

C

hainage 0.000 K

m

E = 489401.407

N = 505465.542

Doves Nest Farm

100m

m

Ø

G

ravity P

ipe

100m

m Ø

Gra

vity P

ipe

225m

m Ø

Gra

vity P

ipe

P

um

pin

g M

ain

80m

m

Ø

Pum

ping M

ain

80mm Ø

Pumpin

g Main

100m

m Ø

1

1

2

2

MH/ Inspection

Chamber

M

H

/ Inspectio

n

C

ham

ber

YORK POTASH LIMITED

PROJECT

DRAWING No.

CONSULTANT

DRAWING No.

DRG SIZE: SCALE:

CLIENT

APPR

REVISION:

ISSUE STATUS DESCRIPTION

DOCUMENT REVIEW

CODE 1: WORK CAN PROCEED

CODE 2: REVISE TO ADDRESS COMMENTS

CODE 3: REJECTED, WORK NOT TO PROCEED

CODE 4: DOCUMENT FOR INFORMATION

SIGNED: DATE:

A1

THIS DRAWING IS A PRIVATE AND CONFIDENTIAL COMMUNICATION

AND THE PROPERTY OF YORK POTASH LIMITED AND MUST NOT

BE COPIED OR LOANED WITHOUT THE PRIOR WRITTEN CONSENT

OF YORK POTASH LIMITED

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21

A

B

C

D

E

F

G

H

J

K

L

M

N

O

P

A

B

C

D

E

F

G

H

J

K

L

M

N

O

P

DRAWING TITLE:

REVPREP CHECKDATE PEM

13 Fitzroy Street

London W1T 4BQ

Tel +44(0)20 7636 1531 Fax +44(0)20 7580 3924

www.arup.com

REFERENCE DESIGN FOR TENDER

COSTING PURPOSES ONLY.

DETAILS SUBJECT TO PLANNING CONSENT

25900-MTS-CD0-2310-00010

TUNNEL DRAINAGE

HORIZONTAL SCHEMATIC LAYOUT

1:25000

E

ZR FMIssued for review

ZR FMRe - Issued for review

ZR FMIssue for DFS & Tender

ZR RHIssue for Tender

B

C

D

E

05/09/14

10/09/14

20/09/14

10/10/14

MS

MS

MS

MS

NOTES:

1. All dimensions in mm unless specified otherwise.

2. This drawing should be read in conjunction with drawing No. 25900-MTS-CD0-2310-12101.

3. Drainage channel @ caverns int. geotextile around g. pipe in cavern locations.

4. Rodding points located within caverns.

LEGEND:

Worksite

Gravity drainage pipework (Ridgidrain ADS filter drainage pipe or equivalent)

Pumped main drainage pipework (SDR 11 PE100)

Appendix B

Capital Cost Estimate

Item Description Qty Unit Rate Price

1 Establishment and Preliminaries

1.1 All in rate for site mobilisation and overheads,(assume 4-6 months)

1 no. £25,000.00 £25,000.00

2 Pumping station, Wet-well and emergency storage

2.1 Twin System one fully duty + one standby pump - 2 x submersible wastewater motor pumps (Power 1.1 kW, Max flow rate: 12.4m3/hr, max head 8m)

2 no. £10,000.00 £20,000.00

2.2 Pump station wet well (including excavation and reinstatment) (1no. Circular concrete chamber, 1.8m diameter x 3m deep)

1 no. £2,500.00 £2,500.00

2.3 Operation and control kiosk with power provision mounted on concrete plinth

1 no £10,000.00 £10,000.00

2.4 Valve chamber (including excavation and reinstatment). Allowance for internal pipework and valves (See figure D4, SFA 7th Ed). Min 1.8m x 2.4m internal dimensions. Chamber walls to be 200mm thick GEN 3 concrete or precast concrete.

1 no. £5,100.00 £5,100.00

2.5 Emergency storage tank offline from pump station. Tank to be

buried formed in GRP. Minimum tank volume 14.4m 3 (2hr allowance at peak plant throughput)

1 no. £5,100.00 £5,100.00

3 Pumped rising main to men and material drift tunnel entrance

3.1 Excavate, remove material and backfill along line of new buried pumped rising main. Assume average 1m depth to trench invert, 0.45m wide trench. Backfill to be Type B granular material to Specification for Highway works clause 505

153 m3 £75.00 £11,475.00

3.2 Install DN63 PN6 PE pipe with associated valves from pump station valve chamber to top of portal entrance. Assume 1No. Air valve and washout valve, with 2No. Gate valves at either end of the main

340 m £80.00 £27,200.00

£0.004 Sewer 1: Gravity drain from Tunnel entrance to Men &

Materials shaft4.1 Form concrete duct to base of tunnel portal with precast

concrete accessible cover160 m £220.00 £35,200.00

4.2 Supply and install DN150 PVC pipe in duct or to tunnel wall 340 m £75.00 £25,500.00

4.3 Install DN1200 concrete manholes at approx 90m spacings. Assume 1.2m deep 4 no. £2,500.00 £10,000.00

£0.005 Sewer 2: Gravity drain from end of tunnel at 70mbgl to Men

& Materials Shaft5.1 Excavate, remove material and backfill along line of buried

gravity drain. Assume average 1m depth to trench invert, 0.45m wide trench. Backfill to be Type B granular material to Specification for Highway works clause 505.

14 m3 not required

5.2 Supply and install DN150 PVC pipe fixed to tunnel wall 30 m £75.00 £2,250.00

5.3 Install DN1200 concrete manholes. Assume 1.2m deep1 no. £2,500.00 £2,500.00

6 Vertical drop from 70mbgl level to 360mbgl level

6.1 Hydro international Vortex Drop Shaft system for energy dissipation. Design to be confirmed by Hydro International

290 m £756.90 £219,500.00

7 Sewer 3: Pressure pipe conveying discharge from drop shaft to energy dissipation tank at base of MTS shaft

7.1 Supply and install DN150 PVC pipe ito tunnel wall 600 m £75.00 £45,000.00

7.2 RC energy dissipation tank at base of MTS shaft with internal concrete baffles. Assume 2m x 2m x 2m

1 no. £15,000.00 £15,000.00

8 Upgrade of 8km length of DN80 PE pipe to DN100

8.1 Material cost differential for DN80 to DN100 pipe 8000 m £5.00 £40,000.00

8.2 Additional installation cost per m (assumed no impact) 8000 no. £0.00 £0.00

9 Misc.

9.1 All consultant fees (assumed 8% of final cost) 8 % £461,325.00 £36,906.00

£538,231.00£161,469.30£699,700.30

Notes1 Assumes that a concrete duct be formed in portal floor slab (4.1)

2 The vertical drop item 6 is based on supply only budget from Hydro International of £150,000

3 The installation of the vertical drop assumes that access will be available for the full height of the shaft complete with crash decks and safety nets

4 The lengths of pipes and consequent joints on the vertical pipe based on maximum length of 6m sections

TOTAL BUDGET ESTIMATE (Excl. VAT)

TOTAL BUDGET ESTIMATE (Excl. VAT)Contingency (30%)

J:\230000\234376‐00\0 Arup\0‐12 Water\0‐12‐07 Calcs‐Specs\01 Domestic Foul Sewer\2014‐11‐21 Disposal to Wilton\2012‐12‐19 DNF Domestic Foul Drainage to Wilton_Cost Est_G&T_Revised tunnel

geometry.xlsx

York Potash - Preliminary Designplanning.northyorkmoors.org.uk/MVM.DMS/Planning...

Documents

Transcript of York Potash - Preliminary Designplanning.northyorkmoors.org.uk/MVM.DMS/Planning...