Detailed EIA Oyu Tolgoi Project Water Supply Pipeline 2009 En

Oyu Tolgoi project DEIA of Water Supply Pipeline

Prepared by ECO-TRADE LLC., Environmental consultants, Mongolia. Client: Ivanhoe Mines Mongolia Inc LLC

i

COMMENTS Table of contents List of tables List of figures List of photos Appendices Abbreviations

TABLE OF CONTENTS BRIEF DESCRIPTION OF THE PROJECT 1.0 INTRODUCTION.................................................................................................................................. 1

1.1 BRIEF DESCRIPTION OF THE PROJECT ................................................................................................. 1 1.2 PROJECT OBJECTIVES AND WATER DEMAND ........................................................................................ 1 1.3 RAW WATER DEMAND OF THE OYU TOLGOI PROJECT ........................................................................... 2 1.4 PROJECT DURATION ............................................................................................................................ 6

2.0 WATER SUPPLY PIPELINE SITE PLAN .......................................................................................... 7 2.1 GENERAL OF WATER SUPPLY SYSTEM ................................................................................................. 7

2.1.1 Bore pump stations ..................................................................................................................... 7 2.2 COLLECTOR AND BREAK TANK STATIONS ........................................................................................... 10 2.3 EMERGENCY STORAGE LAGOON ........................................................................................................ 13 2.4 WATER PIPELINE DESIGN ................................................................................................................... 14

2.4.1 Pipeline cleaning...................................................................................................................... 16 2.4.2 CTPS#1~CTPS#5 and BTPS#1 pipeline layout ......................................................................... 17 2.4.3 Layout of lagoon ...................................................................................................................... 17 2.4.4 Pipeline protection ................................................................................................................... 17 2.4.5 Pipeline excavation and backfill ............................................................................................... 18

2.5 INFRASTRUCTURE REQUIREMENTS .................................................................................................... 19 2.5.1 Fire safety ................................................................................................................................ 19 2.5.2 Heating, Ventilation and air conditioning system ...................................................................... 19 2.5.3 Power supply ........................................................................................................................... 20 2.5.4 Design of distributed control system ......................................................................................... 20 2.5.5 Design of security system.......................................................................................................... 21 2.5.6 Maintenance road .................................................................................................................... 21

2.6 WATER QUALITY ................................................................................................................................ 22 3.0 ENVIRONMENTAL IMPACTS ASSESSMENT OF THE PROJECT ............................................. 23

3.1 METHODOLOGY OF ASSESSMENT ...................................................................................................... 23 3.2 MAIN ASSESSMENT METHODS............................................................................................................ 25

4.0 CLIMATE ............................................................................................................................................ 25 4.1 CHARACTERISTICS OF CLIMATE ......................................................................................................... 25

4.1.1 Basic meteorological parameter ............................................................................................... 27 4.2 IMPACTS OF OYU TOLGOI WATER SUPPLY PIPELINE FOR CLIMATE .................................................... 28

4.2.1 Impacts of climate for Water Supply Pipeline project ................................................................ 29 4.3 MITIGATION MEASURES FOR THE NEGATIVE IMPACTS......................................................................... 29 4.4 IMPACTS ON AIR QUALITY AND ITS ASSESSMENT ................................................................................ 30

4.4.1 Main indicators of air quality ................................................................................................... 30 4.4.2 Impacts on air quality and its assessment .................................................................................. 31 4.4.3 Mitigation measures for the negative impacts on air quality ...................................................... 32

5.0 IMPACT ASSESSMENT ON SOIL SURFACE AND SUBSOIL, THEIR ASSESSMENT .............. 33 5.1 LOCATION OF OYU TOLGOI WATER SUPPLY PIPELINE PROJECT AND GENERAL INDICATORS ............... 33 5.2 IMPACT ASSESSMENT OF LANDSCAPE AND SUBSOIL ........................................................................... 34 5.3 MITIGATION MEASURES FOR THE NEGATIVE IMPACTS FROM THE WATER SUPPLY PIPELINE ................. 37

6.0 IMPACT ASSESSMENT ON SURFACE AND GROUNDWATER .................................................. 38 6.1 SURFACE AND GROUNDWATER AT PROPOSED AREA FOR WATER SUPPLY PIPELINE ............................ 38 6.2 GROUNDWATER ................................................................................................................................ 39 6.3 IMPACT ASSESSMENT ON SURFACE AND GROUNDWATER ................................................................... 41 6.4 MITIGATION MEASURES FORTHE NEGATIVE IMPACTS ......................................................................... 43

7.0 IMPACT ASSESSMENT ON SOIL .................................................................................................... 45



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7.1 SOIL DESCRIPTION OF THE AREA ....................................................................................................... 45 7.1.1 Grey brown soil of desert steppe ............................................................................................... 47 7.1.2 Light clayey brown soil of desert steppe .................................................................................... 47 7.1.3 Sandy brown soil of desert steppe ............................................................................................. 47 7.1.4 Aeolian sands ........................................................................................................................... 47 7.1.5 Meadow grey brown soil of desert steppe .................................................................................. 48 7.1.6 Saline grey brown soil of desert steppe ..................................................................................... 48

7.2 IMPACT ASSESSMENT ON SOIL COVER ............................................................................................... 48 7.2.1 Mitigation measures for the negative impacts ........................................................................... 50

8.0 IMPACT ASSESSMENT ON FLORA ................................................................................................ 51 8.1 CURRENT CONDITION OF VEGETATION COVER ................................................................................... 51

8.1.1 Vegetation of water supply pipeline project area ....................................................................... 55 8.1.2 Desert peneplain (Vegetation cover of low hills, plain valleys and ridges) ................................. 57 8.1.3 Desert steppe ........................................................................................................................... 57 8.1.4 Low hills .................................................................................................................................. 57 8.1.5 Ephemeral creeks and saline marshes ....................................................................................... 57 8.1.6 Vegetation on depositional sands (Saxsaul wood) .................................................................... 57

8.2 IMPACT ASSESSMENT ON VEGETATION COVER ................................................................................... 57 8.3 MITIGATION MEASURES FOR THE NEGATIVE IMPACTS......................................................................... 59

9.0 IMPACT ASSESSMENT ON FAUNA ................................................................................................ 60 9.1 FAUNA OF PROJECT AREA ................................................................................................................. 60 9.2 MITIGATION MEASURES FOR THE NEGATIVE IMPACTS ......................................................................... 61

10.0 PHYSICAL POLLUTION TO THE ENVIRONMENT IN TERMS OF WATER SUPPLY PIPELINE PROJECT .................................................................................................................................. 63

10.1 IMPACT ASSESSMENT OF NOISE AND VIBRATION CONDITION .............................................................. 63 10.1.1 Impact assessment .................................................................................................................... 63 10.1.2 Mitigation measures for the negative impacts ........................................................................... 64

11.0 IMPACT ASSESSMENT ON HISTORICAL AND CULTURAL HERITAGE ................................ 65 11.1.1 Mitigation measures for the negative impacts ........................................................................... 65

12.0 IMPACT ASSESSMENT ON SOCIO-ECONOMICS ........................................................................ 66 12.1 SOCIO-ECONOMIC CONDITION OF THE UMNUGOBI PROVINCE ............................................................. 66

12.1.1 Population, social condition ..................................................................................................... 66 12.1.2 Agriculture ............................................................................................................................... 69 12.1.3 Industry.................................................................................................................................... 70

12.2 BRIEF DESCRIPTION OF THE KHANBOGD SUM .................................................................................... 70 12.3 IMPACT ASSESSMENT OF SOCIO-ECONOMICS .................................................................................... 70

13.0 SUMMARY OF THE ENVIRONMENTAL IMPACT ASSESSMENT ............................................. 73 14.0 RISK ASSESSMENT........................................................................................................................... 74

14.1 NATURAL DISASTERS AND POTENTIAL RISKS RELATED TO EQUIPMENTS AND TECHNOLOGY ................ 74 14.1.1 Natural disasters and related risks: .......................................................................................... 74 14.1.2 Risk and danger caused by equipments and technology ............................................................. 76

14.2 MITIGATION MEASURES FOR THE POTENTIAL RISKS ........................................................................... 77 15.0 ENVIRONMENTAL PROTECTION PLAN ...................................................................................... 80 16.0 ENVIRONMENTAL MONITORING PLAN ..................................................................................... 88 17.0 RELEVANT LEGISLATION TO THE PROJECT ........................................................................... 93 18.0 SUMMARY OF ENVIRONMENTAL IMPACT ASSESSMENT FINDINGS ................................ 100



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List of Tables Table 1.1 Plant Raw Water Demand Requirements of the Oyu Tolgoi, L/s .......................................... 4 Table 1.2 Water demand management options of the water supply pipeline ...................................... 6 Table 2.1 Location and area of the bores............................................................................................ 8 Table 2.2 Production Bores Flow Rate ............................................................................................... 9 Table 2.3 General parameters of bore pump system .......................................................................... 9 Table 2.4 Location and area of the CTPS ..........................................................................................11 Table 2.5 Technical parameters in Pump House CTPS#1~CTPS#5 and BTPS #1 .............................12 Table 2.6 Borehole to CTPS#1~ CTPS#5 Pipeline Parameters .........................................................15 Table 2.7 Main pipeline parameter ....................................................................................................16 Table 2.8 Excavation Depth for Pipe Trenches ..................................................................................18 Table 2.9 Trench slope versus soil types and depths .........................................................................18 Table 2.10 Heating, Ventilation, and Air Contioning Design Considerations for BPS, CTPS and BTPS .........................................................................................................................................................20 Table 4.1 Air temperature in Oyu Tolgoi and its surrounding area, by months ....................................26 Table 4.2 Soil temperature in Oyu Tolgoi and its surrounding area , by months .................................26 Table 4.3 Climate Impact Assessment...............................................................................................29 Table 4.4 Location of the monitoring ..................................................................................................29 Table 4.5 Emission Factors for Diesel Industrial Vehicle Exhaust Emissions (based on engine power) .........................................................................................................................................................31 Table 4.6 Air Quality Impact Assessment ..........................................................................................32 Table 5.1 - ..........................................35 Table 5.2 - , ............................36 Table 5.3 Impact assessment on landscape and subsoil....................................................................37 Table 6.1 Wells located along the water supply pipeline project implementing area ...........................40 Table 6.2 Pumping Test Groundwater Quality Gunii Hooloi Aquifer....................................................41 Table 6.3 Temporal runoff beds crossing water supply pipeline at Gunii Hooloi groundwater reserve .42 Table 6.4 Qualitative Assessment of Impacts on Surface and Groundwater .......................................43 Table 7.1 Soil field records and location of sample ............................................................................46 Table 7.2 Main agrochemical parameters of soil ................................................................................46 Table 7.3 Impact Assessment of Soil .................................................................................................50 Table 8.1 Detailed list of vegetation composition at Gunii Hooloi borefield and pipeline ......................52 Table 8.2 List of Endemic plants ........................................................................................................53 Table 8.3 List of plants included in list of rare plants of Mongolia .......................................................54 Table 8.4 List of Plants included in list of very rare plants of Monglolia...............................................54 Table 8.5 Vegetation Classification of Water Supply Pipeline Project .................................................56 Table 8.6 Impact Assessment of Fauna .............................................................................................58 Table 9.1 Impact Assessment of Fauna .............................................................................................61 Table 10.1 Impact Assessment of Noise and Vibration ......................................................................64 Table 11.1 List of archeological memorials ........................................................................................65 Table 12.1 Impact assessment of the water supply pipeline project ...................................................72 Table 13.1 Summary of EIA of the .....................................................................................................73 Table 14.1 Seismicity registered at Oyu Tolgoi project area ...............................................................74 Table 14.2 Risk Assessment .............................................................................................................77 Table 15.1 Environmental Protection Plan .........................................................................................81 Table 16.1 Environmental Monitoring Plan ........................................................................................89 Table 17.1 Mongolian laws on environment .......................................................................................93 Table 17.2 Mongolian National Standards and Codes .......................................................................96 Table 17.3 International Standards and Codes ..................................................................................96 Table 17.4 Existing Mongolian standards on Gunii Hooloi Borefield and water supply pipeline project of the Oyu Tolgoi ...............................................................................................................................98

List of Figures Figure 1.1 Site, Infrastructure and Plant Raw Water Demand, L/s ....................................................... 5 Figure 2.1 Maintenance road design .................................................................................................22 Figure 3.1 Expert assessment matrix.................................................................................................24 Figure 4.1 Wind Rose for the Oyu Tolgoi project area ........................................................................27 Figure 12.1 Birth, mortality and net growth of population of Umnugobi aimag (2004-2007).................67 Figure 12.2 Number of the infected people, especially infected by hepatitis, in Umnugobi aimag .......67 Figure 12.3 Educational level of the registered unemployed people of Umnugobi aimag ....................68



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Figure 12.4 Volume and structure of the livestock herds in Umnugobi aimag .....................................69 List of Photos Photo 1. General position of the lagoon .............................................................................................13 Photo 2. Proposed position of water supply pipeline ..........................................................................34 Photo 3. Ephemeral creek in the Khaliviin valley ................................................................................39 Photo 4. Khulans at the project area during the fauna field survey .....................................................60

Appendices

Appendix 1.1 Oyu Tolgoi project location Appendix 1.2 Raw water supply pipeline project location Appendix 2.1 Oyu Tolgoi water supply system schematic drawing Appendix 2.2 Bore pump location of the borefield Appendix 2.3 Bore pump station GH01_PB01site plan Appendix 2.4 Bore pump station GH01_PB01 elevation Appendix 2.5Collector tank pump station CTP#1 plan Appendix 2.6 Collector tank pump station CTP#1 elevation Appendix 2.7 General site plan of lagoon Appendix 2.8 Collector tank pump station, CTP1 pumping plan Appendix 2.9 Collector tank pump station CTP1 pipeline section Appendix2.10 Break tank pump station BTP1 pipeline plan sheet 2 of 1 Appendix 2.11 Break tank pump station BTP1 pipeline plan sheet 2 of 2 Appendix 2.12 Pipeline typical cross sections Appendix 4.1 Location of meteorological stations around the project location Appendix 5.1 Project location and administrative units Appendix 5.2 Project area landscape and its impact assessment Appendix 5.3 Main water supply pipeline longitudinal section Appendix 7.1 Soil cover of the project area Appendix 8.1 Vegetation of the project area Appendix 8.2 Rare and very rare plants location at the project area Appendix 11.1 Location of archeological sites around the project area Appendix 14.1 Seismicity zones in Mongolia and project location Appendix 14.2 Earthquake events in 100 years since 1900 and project location



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Abbreviations

IMMI - Ivanhoe Mines Mongolia Inc

- Oyu Tolgoi

RWSP - Raw Water Supply Pipeline

DEIA - Detailed Environmental Impact Assessment

MNE - Ministry of Nature and Environment

BPS - Bore Pump Station

CTP - Collector Tank Pump

BTPS - Break Tank Pump Station

CTPS - Collector Tank Pump Station

L- Lagoon

HT - High Transmissvity

LT - Low Transmissivity

DICL - Ductile Iron Cement Lined

HDPP - High-Density Polyethylene Pipe

CS - Carbon Steel

FRP - Fiberglass-Reinforced Plastic



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EXECUTIVE SUMMARY OF THE SUPPLEMENTARY DETAI LED IMPACT ASSESSMENT

REPORT FOR THE GUNII HOOLOI BOREFIELD AND PIPELINE WATER SUPPLY OF

THE OYU TOLGOI PROJECT

October, 2008

In accordance with the order of Ivanhoe Mines Mongolia Inc (IMMI), the proponent of the

Oyu Tolgoi copper and gold mining project in Khanbogd sum of Umnugobi Aimag, Mongolia,

this Supplementary Detailed Environmental Impact Assessment (SDEIA) report for the Gunii

Hooloi Borefield and Pipeline water supply project has been prepared by the Eco Trade LLC,

Mongolia.

This SDEIA report is for the Gunii Hooloi Borefield and Pipeline project which originates at

the Gunii Hooloi groundwater resource area and extends to the storage lagoon of the Oyu

Tolgoi copper and gold processing plant. The SDEIA presents a detailed description of the

project, technology details, and potential impacts to the environment from the Gunii Hooloi

Borefield and Pipeline construction and its operation. The SDEIA includes mitigation

measures and an attached Environmental Protection Plan and Environmental Monitoring

Plan.

IMMI completed project water supply investigations from 2002 to 2004 which identified and

defined the Gunii Hooloi groundwater aquifer and has calculated the available groundwater

reserve of the water supply.

Water demand for the Oyu Tolgoi mine has been estimated with an average yearly demand

696 L/s based on peak year for 110,000 tonnes per day for the mine development, 64%

tailings density and 0% mine dewatering. A margin of 150 L/s for lagoon refilling of its

emergency use, the indicated design capacity requirement for the borefield / pipeline is 935

L/s. The water demand of the Oyu Tolgoi mine will be more in initial years than yearly

average water demand in other years until drainage water will be possible to reuse.

The proposed corridor for the pipeline and pumping stations for the Oyu Tolgoi project begins

at Gunii Hooloi located 25 km from the northeast of the Oyu Tolgoi license area and

continues 70 km to the Oyu Tolgoi project area.

The project water supply system facilities include 28 production and 5 standby bores, 5

collector pump stations, approximately 148.9 km of pipe, a raw water storage pond with a

capacity of 400000 m3 break pump station including 110 MW electricity transmission lines, a

maintenance road and other facilities. The water supply system facilities occupy an

estimated total area of 1030 ha.



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Production bores are proposed to be developed in two distinct areas of the Gunii Hooloi

Borefield; 12 water bores in the southern portion of the southeast part of the borefleld which

are predicted to provide 30 L/s per bore in the low transmissivity (LT) and 21 water bores in

the higher transmissivity (HT) northeast part of the borefield which are estimated to provide

40 L/s per bore.

Powerlines linking the borefiled pumps with the Oyu Tolgoi site power supply will generally

follow the pipeline corridor. An access road for maintenance and inspection is planned in the

pipeline corridor.

A 400,000 m3 capacity, emergency raw water storage pond will be located on elevated

ground approximately 5 km north of the Oyu Tolgoi mining and processing site to provide an

emergency supply of water to the site in the event of a pipeline failure. Water supply from the

emergency storage lagoon to the site will be carried within two pipelines.

A Detailed EIA report on the potential impacts of groundwater use from the Gunii Hooloi

aquifer was prepared by Eco Trade LLC and approved by the MNE, April in 2005. The

approved EIA for the use of the aquifer did not include the details of the borefield

Infrastructure and pipeline as design of these facilities was not complete at the time. Field

observations, laboratory analysis, and identification of applicable Mongolian and International

legal requirements, standards, regulations and legislation during the construction and

operation phase were completed for the SDEIA of this project in July, 2007.

DEIA report is supplementary to "Environmental Impact Assessment report for Oyu Tolgoi

Project Groundwater Resource Use from the Gunii Hooloi and Galbyn Gobi Regional

Aquifers" completed by Eco Trade LLC and approved by MNE.

The identification of potential environmental impacts from the Gunii Hooloi Borefield and

Pipeline water supply was completing using a risk matrix which considers potential impacts

and severity. The SDEIA indicates that the impact on the environment from Gunii Hooloi

Borefield and Pipeline Water Supply is temporary and limited to the immediate area of the

infrastructure. These localized impacts can be minimized during construction through

implementation of technical procedures for removal of soil and vegetation, and excavation

and installation of pipe stations and other facilities.

Potential short term negative impacts may occur on air quality from dust emissions during

installation and the construction of pipeline facilities (pipeline, collector and break tank pump

stations , emergency lagoon, service road and electric line), soil stripping and stockpiling,

and gaseous emission from vehicles used during construction. There is not direct impact to

cultural heritage and climate. According to archeology research done there are not burial and

memorials alongside the pipeline site .



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The development and operation of the Gunii Hooloi Borefield and Pipeline project will be

undertaken to minimize impacts to the environment through application of the Environmental

Protection Plan and the Environmental Monitoring Plan.

Prepared by: Oyuntuya.S

Expert of Eco trade LLC, Environmental Assessment and Expertise Company.

"" m


Prepared by ECO-TRADE LLC., Environmental Consultants, Mongolia. Client: Ivanhoe Mines Mongolia Inc LLC

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1.0 INTRODUCTION

11..11 BBRRIIEEFF DDEESSCCRRIIPPTTIIOONN OOFF TTHHEE PPRROOJJEECCTT

Project name: OYU TOLGOI RAW WATER SUPPLY PIPELINE PROJECT Project proponent:

Ivanhoe Mines Mongolia Inc LLC (IMMI) is the development proponent of the Oyu Tolgoi raw

water supply pipeline project and is holded 6709A mining license at the Oyu Tolgoi

(Appendix 1.1 Oyu Tolgoi project location).

Project location: This project will be implemented in the Jargalant bag of the Khanbogd

sum in the Umnugobi province and that pipeline will be lied about 82.2 km from the Gunii

Hooloi aquifer areas to the Oyu Tolgoi project area. Total width of the pipe is between 60

and 70 km which will be approximately 40 km narrow around the south of the Khanbogd

mountain (Appendix 1.2 Raw water supply pipeline project location).

Project capacity: The peak design water demand rate of 745 L/s and the pipeline capacity

is 895 L/s of the water pipeline system. Pipeline system consist main 28 boreholes, 4

standby boreholess, a capacity of 400,000 m3 emergtency storage lagoon, collection and

break tank pumps, length of 148.9 km underground pipeline, capcacity of 110 kW powerline

and maintenance road covering 1030 hectares. The system will work during the operation.

DEIA executive: A Detailed Environmental Impact Assessment of Oyu Tolgoi

projectGroundwater Resource Use from the Gunii Hooloi and Galbyn Gobi Regional

Aquifers, Volume II report was submitted by MNE in June, 2005 and approved in

September, 2005. DEIA of the project was prepared by Eco Trade LLC, Environmental

Consultants, Mongolia.

11..22 PPRROOJJEECCTT OOBBJJEECCTTIIVVEESS AANNDD WWAATTEERR DDEEMMAANNDD

Oyu Tolgoi water supply pipeline project is one of the certain significant which will supply raw

water demand of the Oyu Tolgoi mine processing in Khanbogd sum of Umnugobi province.

The raw water supply project is included in Oyu Tolgoi mine processing plan in September

2005.

Following procedures requires to construc the Oyu Tolgoi water supply pipeline:



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1. To supply continuously water demand for the Oyu Tolgoi mining and processing

during the its operation,

2. Water supply of dust suppression from the construction and operation period of Oyu

Tolgoi project,

3. Water supply of the air Oyu Tolgoi power plant,

4. Raw water that will be directed for domestic use will be fully treated in the Oyu Tolgoi

water treatment and bottling plant.

11..33 RRAAWW WWAATTEERR DDEEMMAANNDD OOFF TTHHEE OOYYUU TTOOLLGGOOII PPRROOJJEECCTT

Accordance with order of IMMI LLC, Fluor group studied water demand of Oyu Tolgoi project

based on water suply resource and water demand for the operation period prepared for IMMI

LLC. This report based on Oyu Tolgoi raw water supply pipleine detailed engineering design

report in August, 2008.

Water demands for the mine vary depending on the level of production within the mine

operations. Preliminary information from Technical Discussion Memorandum TDM201 Site

Water Balance and Design Criteria for GH Pipeline_Rev2 is that production within the mine

is proposed to commence with a production rate around 70,000 t/d possibly during years 1

to 3 of operation, increasing to a production rate of 85,000 t/d during years 4 to 8 of

operation and 170,000 t/d up to year 16.

The peak design demand rate for the 85,000 t/d, 64% tailings density and 0% mine

dewatering scenario is recommended to be carried forward for pipeline sizing purposes

(Table 1.1).

Plant design water demand:

The plant raw water demand ranges from 535 to 671.2 L/s, with an average yearly demand

of 627 L/s.

Infrastructure and Mining Raw Water Demand:

1. Domestic Water Supply 400 people living continuously on site at a consumption

rate of 0.27 m3 per person per day. 1900 people working but not living on site a

consumption rate of 0.135 m3 per person per day. For the this water consumtion is

4.2 L/s throughout year.



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2. Steam Boiler System Makeup Water It rates between 0.1-6.3 L/s and average rate

is 2.6 L/s. This water consumption is 0.1 L/s in summer to 6.3 L/s in winter.

3. Glycol Heating System Makeup Water According to estimation the water

consumption is 1.2 L/s from November to April in winter time and maximum water

demand is 2.8 L/s.

4. Ongoing Construction Activities (including Concrete Batch Plant) It is 0.3 L/s in

winter to 0.8 L/s in summer, average is 0.6 L/s.

5. Sewage Return and Primary Crusher water demand has been transferred to the plant

water balance.

6. Truck Wash - Each month truck wash will be done and 1.7 L/s throughout the year.

7. Power Plant 7.6 L/s in winter to 9.5 L/s in summer, average demand is 8.5 L/s.

8. Infrastructure Dust Suppression It will be depends on seasons and 11.5 L/s in June

July. There is no water use for the dust suppression activity in winter time. Average

water demand is 3.3 L/s.

9. Open Pit Mine Dust Suppression The water demand ranges from 0 and 57.5 L/s

throughout the year with average yearly demand of 16.6 L/s.

10. Underground Mine 30 L/s throughout the year.



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Table 1.1 Plant Raw Water Demand Requirements of the Oyu Tolgoi, L/s

A

Plant Raw Water Demand (L/s)

Mine dewatering scenario

Plant capacity 6 7 8 9 10 11 12 1 2 3 4 5 Average Maximum

0% Dewatering Design (110.000 t/day)

670.1 671.2 625.1 640.3 607.3 548.7 638.7 635.9 639.8 534.8 657.8 650.6 627.5 671.2

Water Demand User Infrastructure/Mining Raw Water Demand (L/s)

6 7 8 9 10 11 12 1 2 3 4 5 Average Maximum

1 Domestic Water Supply 4.2 4.2 4.2 4.2 4.2 4.2 4.2 4.2 4.2 4.2 4.2 4.2 4.2 4.2

2 Sewage return

3 Steam boiler System Makeup water 0.1 0.1 0.1 0.1 0.1 2.8 6.3 6.3 6.3 6.3 2.8 0.1 2.6 6.3

4 Glycol Heating System Makeup Water

0 0 0 0 0 1.4 2.8 2.8 2.8 2.8 1.4 0 1.2 2.8

5 Ongoing Construction Activities (inc. Concrete Batch Plant)

0.8 0.8 0.8 0.8 0.8 0.8 0.3 0.3 0.3 0.3 0.8 0.8 0.6 0.8

6 Primary crusher

7 Truck wash 1.7 1.7 1.7 1.7 1.7 1.7 1.7 1.7 1.7 1.7 1.7 1.7 1.7 1.7

8 Power Plant 9.5 9.5 9.5 9.5 9.5 7.6 7.6 7.6 7.6 7.6 7.6 9.5 8.5 9.5

9 Infrastructure Dust Suppression 11.5 10 7.2 3 0 0 0 0 0 0 2.4 5.7 3.3 11.5

10 Open Pit Mine Dust Suppression 57.5 50 36 15 0 0 0 0 0 0 12 28.5 16.6 57.5

11 Underground Mine 30 30 30 30 30 30 30 30 30 30 30 30 30 30

B Total Infrastructure/Mining Demand 115.3 106.3 89.5 64.5 46.3 48.5 52.8 52.8 52.8 52.8 62.9 80.5 68.8 115.3

A+B total Design (110.000 t/day)

785.4 777.6 714.6 704.6 653.6 597.2 691.5 688.7 692.6 587.6 720.7 741.1 696.3 785.4

Source: Raw Water Supply Pipeline Detailed Engineering Report, Fluor group, Aug, 2008.



Page-5

Total water demand of plant raw water demand and infrastructure / mining water demand is

110,000 tonn per day with 64% availability factor and 0% mine dewatering. Site design water

demand ranges from 588 L/s to 785 L/s, with an average yearly demand of 696 L/s (Figure 1.1).

0

100

200

300

400

500

600

700

800

900

1 2 3 4 5 6 7 8 9 10 11 12

Month

De

ma

nd

Flo

w R

ate

L/s Plant Design Demand (L/s)

Site Design Demand (L/s)

Infrastructure Demand

(L/s)

Figure 1.1 Site, Infrastructure and Plant Raw Water Demand, L/s

It is probable that water supply will be decreased from water supply pipeline in winter period, and

water supply will be increased in high evaporation period.

Three options for the improvements of the raw water supply sysytem have been examined.

According to the scenario the peak design water demand rate of 785 L/s and it is recommended

that a lower margin of 115 L/s is adopted for lagoon refilling (Table 1.2 Raw water demand

management options). The below table shown the pipeline / borefield design capacity is estimated

of 900 L/s.

A 400,000 m3 emergency / buffer storage lagoon is recommended that wil provide approximately

one weeks emergency supply to the site in the event of a major borefield / pipeline failure.

Inclusive of a margin of 150 L/s for lagoon refilling within one month of its emergency use, the

indicated design capacity requirements for the borefield / pipeline is 935 L/s.



Page-6

Table 1.2 Water demand management options of the water supply pipeline

Options Option 1. Increased Emergency Storage

(m3)

Op

tio

n 2

. Y

earl

y R

aw

W

ate

r D

em

an

d

Bala

ncin

g (

m3)

Option 3. Yearly Raw Water Demand Balancing plus increased Emergency Storage

(m3)

Min

e

Dew

ate

ring

options

Pla

nt

capcaic

ty

2 hours

12 hours

1 day

2 days

1 week

2 weeks

2 hours

12 hours

1 hour

2 days

1 week

2 weeks

Min

e D

ew

ate

ring 0

%

Desig

n w

ate

r dem

and

(110.0

00 t

/d)

5013 30079 60158 120316 421107 842214 984564 989577 1014643 1044722 1104880 1405671 1826778

Borefield and pipeline design

parameters

Mine water demand: 785 L/s + Borefield and pipeline:115 L/s = 900 L/s

Average water demand - 696 L/s

Source: Raw water supply pipeline detailed engimeering design report, Flour group, Aug, 2008.

11..44 PPRROOJJEECCTT DDUURRAATTIIOONN

The water supply pipeline project is one of the significant infrastructure of the Oyu Tolgoi project.

The project is proposed to supply water demand of Oyu Tolgoi project from the Gunii Hooloi

borefield in whole project duration. According to the preliminary estimation, Oyu Tolgoi mining and

processing operation will be for 60 years. The water supply pipeline system designed during the

operation continuously.



Page-7

2.0 WATER SUPPLY PIPELINE SITE PLAN

22..11 GGEENNEERRAALL OOFF WWAATTEERR SSUUPPPPLLYY SSYYSSTTEEMM

The detailed engineering design of the water supply pipeline and borefield at the Oyu Tolgoi covers

the following aspects:

Access and borefield road;

Piping and fittings;

Pump stations and water collector tank;

Lagoon;

Electrical, fire protection instrumentation, guard fence and communication systems.

According to the profile diagram of pipeline of 33 bore pump system, two groups can be divided.

The whole system consists of 5 collector tank pump station (CTPS#1~ CTPS#5) which collect

pressure flow from the Borehole pump station (BTPS#1), and boosted again to lagoon far away,

from which gravity flow runs to the site (Appendix 2.1 Oyu Tolgoi water supply system schematic

drawing ).

2.1.1 Bore pump stations

The OT water supply system obtains water from the bore fields of the High Transmissivity (HT)

area and the Low Transmissivity (LT) area, respectively including 21 bores with design flow rate of

40 L/s each and 12 bores with 30 L/s (Appendix 2.2 Bore pumps locaton of the borefield).



Page-8

Table 2.1 Location and area of the bores

No. Of bores Latitude (m) Longitude (m) Area (m) Aquifer area

GH01_PB01 697500 4814000 625

HT zone

GH01_PB02 697370 4812090 625

GH01_PB03 699500 4812000 625

GH01_PB04 699500 4810000 625

GH01_PB05 695500 4812000 625

GH01_PB06 696007 4813515 625

GH01_PB07 700750 4810709 625

GH02_PB01 691391 4810202 625

GH02_PB02 693658 4811345 625

GH02_PB03 693474 4808009 625

GH02_PB05 695500 4808000 625

GH02_PB06 697500 4810000 625

GH02_PB07 697424 4808524 625

GH03_PB01 689500 4806000 625

GH03_PB02 691500 4808000 625

GH03_PB04 689500 4804000 625

GH03_PB05 692368 4805110 625

GH03_PB06 693500 4806300 625

GH03_PB07 689500 4808000 625

GH04_PB01 681400 4801010 625

LT zone

GH04_PB02 682500 4804000 625

GH04_PB03 681347 4802834 625

GH04_PB04 682387 4798517 625

GH04_PB05 684500 4802000 625

GH04_PB06 685000 4804500 625

GH05_PB01 673500 4797000 625

GH05_PB02 676419 4798866 625

GH05_PB04 675500 4795000 625

GH05_PB05 678161 4797735 625

GH05_PB06 679000 4800000 625

Source: Fluor group, 2MW-6100-10C-200

The production bores will achieve a combined flow rate of 900 L/s. Production bores flow rate are

shown in Table 2.2.



Page-9

Table 2.2 Production Bores Flow Rate

LT area HT area

Total flow (L/s) No. of

bores

Flow per bore (L/s)

Total flow (L/s)

No. of bores

Flow per bore (L/s)

Total flow (L/s)

10 30 300 18 40 720 1020

2* 30 60 3

* 40 120 180

Source: Raw water supply pipeline detailed engineering design for bore location updated design report , Flour group, Aug 2008.

Note: * represents the installed standby capacity

Pump station is set for every production bore. Bore pump station hoist water from the raw water

storage pond and deliver to the collection tank pump. Each bore pump station will comprise a

modular structure containing the water bore, bore pump equipment, headworks, electrical

distribution panels and pipeline connection (Appendix 2.3 Bore pump station GH01_PB01site

plan).

With reference to the layout of mechanical and electrical equipment, the borehole pump house has

a design plan size of 4.8x8.0 m and height of 4.445 m and double-sloped roof. For maintaining the

suction pipe, the manhole in 1000 mm diameter is set at the roof. For installing equipment, the

pump house gate is sized 1500x2400 mm.

For cold climate protection, windows have double-layered glass, and the exterior gate is of

insulation-type steel.

With reference to operating conditions, the bore pump house adopts lightweight steel structure for

portal rigid frame, wall grider, gable column and purlin, and color coated steel sandwiched with

PVC benzene board for insulation. According to structural calculation, walls and roofs adopt 150

mm-thick boards sandwiched within steel plates of 0.8 mm thick; wall griders, gable columns and

purlins are of C-type lightweight steel, portal rigid frame is of H-type high frequency welded

variable-section lightweight steel structure.

Foundation is of the independent type below columns and connected with bracing beams in

adepth of over 2.2 m. The reinforced concrete foundation uses C35 concrete. This report attached

general architecture and design of the bore pump station. (Appendix 2.4 Bore pump station

GH01_PB01 elevation).

Gunii Hooloi borefield and water supply pipeline system consists total area of 2.0625 (for 33 bores)

hectares and bore pump station construction with its outside protection fence for each bore. Table

2.3 shown general parameters of the bore pump system.

Table 2.3 General parameters of bore pump system

No Types Size Area

1 Protection fence 25 m 25 m 625 m2



Page-10

2 Protection fence (for 33 bore pumps) (25 m 25 m)x33 625*33=20625 m2 or 2.0625 ha

3 Bore pump station 8 m x 4.8 m 38.4 m2

4 Bore pump station (for 33 bore pumps ) (8 m 4.8 m) x 33 38.4*33=1267.2 m2

Source: Bore Pump Station General layout (A2MW-6110-10C-025),Gunii Hooloi borefield and Pipeline project

22..22 CCOOLLLLEECCTTOORR AANNDD BBRREEAAKK TTAANNKK SSTTAATTIIOONNSS

Water is delivered from the water bores to collection tanks via low pressure high density

polyethylene pipelines. Collection tank will serve groups of bores for the collection and onward

pumping of raw water to the emergency storage lagoon and Oyu Tolgoi site. CTPS#1-CTPS#5 will

be constructed depends on bore pump parameters and flow rate of the borefield and location and

area of the CTPS shown in Table 2.4.

Each collector tank will have approximately 1 hour storage and will include a series of horizontal

split case centrifugal pums including variable speed drive, magnetic flowmeter and rainage pumps.

(Appendix 2.5 Collector tank pump station CTP1 pipeline plan).

One operational and one standby pump will be provided for each of the two collection tanks in the

low transmissivity south-west part of the borefield and two operational and one standby pump will

be provided for each of the three collection tanks in the high transmissivity north-east part of the

borefield (Table 2.4).



Page-11

Table 2.4 Location and area of the CTPS

No. of pump station Latitude (m) Longitude (m) Area () Borefield

aquifer area

CTPS#1 697295.02 4811780.88 5688

HT zone CTPS#2 694820.69 4809230.18 5688

CTPS #3 690844.73 4805587.32 5688

CTPS#4 681699.5 4800947.2 5688 LT zone

CTPS#5 675227.91 4796579.97 5688

#1 672505 4793168 6216

Source: Fluor group, 2MW-6100-10C-200

As requirement by pump layout, equipment room of CTPS#~CTPS#5 and BTPS#1 pump house is

of semi-underground type. Equipment room, based on installation and lifting requirement, has a

building height of 6.4 m, and electrical room of 4.3 m. Pump houses have double roofs with slope

of 1:12. For requirements of equipment installation and maintenance and ramp of 4.2 m wide is

arranged at extreme end in equipment room for convenience of transport and installation.

Windows sized as 3600 x 1500 mm are set in the front wall. For cold climate protection, windows

have double-layered glass, and the exterior gate is of insulation-type steel.

CTPS#1~CTPS#5 and BTPS #1 pump houses adopt lightweight portal steel structure, and walls,

and roofs use insulation type sandwiched board. According to electro-mechanical calculation, walls

and roofs adopt 150 mm thick boards sandwiched within steel plates of 0.8 mm thick; wall griders,

gable columns and purlins are of C-type lightweight steel, portal rigid frame is of H-type high-

frequency welded variable section lightweight steel structure (Appendix 2.6 General layout of

CTPS#1). In the detail design based on water regulation, the collector tank and break tank have

three types of storage capacity respectively 300 m3, 400 m3 and 600m3, CTP#1~CTP#3 have

design capacity of 2 x 400 m3, CTP#4~CTP#5 of 2 x 300 m3, BTPS#1 of 2x600 m3. Structural

calculation are based on cast-in-place concrete. Structural calculations have been made for tank

wall, top and base slabs using respectively substition framework method and no beam cover

structure.

Below Table 2.5 shown technical parameters of the CTPS#1~CTPS#5 and BTPS#1.



Page-12

Table 2.5 Technical parameters in Pump House CTPS#1~CTPS#5 and BTPS #1

Layout of pump house

CTPS#1 CTPS#2 CTPS#3 CTPS#4 CTPS#5 BTPS#1

Plan size 45.87512.0m 45.87512.0m 51.87512.0m 38.37512.0m 38.37512.0m 69.87518.0m

Building height 6.404 m 6.404 m 6.404 m 6.404 m 6.404 m 6.404 m

Electrical room 4.3 m 4.3 m 4.3 m 4.3 m 4.3 m 4.3 m

Equipment installation and maintenance

4.2m, 12 slope

4.2m, 12

slope 4.2m, 12

slope 4.2m, 12

slope 4.2m, 12

slope 4.2m, 12

slope

Water capacity 2300 m3 2300 m

3 2300 m

3 2300 m

3 2300 m

3 2600 m

3

Pump parameters

2 duty, 1 standby, Q=432m

3/h,

H=188m and N=315 kW


3/h,

H=156m and N=250kW

2 duty, 1standby, Q=432 m

3/h,

H=105m and N=315kW


3/h

H=38m and N=90kW


3/h

H=31b and N=75kW


3/h,

H=237m and N=1000kW

Maintanence of Equipment and Valve (gantry crane features)

5t weight, 9.0m lifting height, 11.0m span, 7.5kW electric hoist, 0.8kW small trolley and and 20.8 kW big trolley

5t weight, 9.0m lifting height, 11.0m span, 7.5kW electric hoist, 0.8kW small trolley and and 20.8 kW big trolley

3t weight, 9.0m lifting height, 11.0m span, 4.5kW electric hoist, 0.4 kW small trolley and 20.8 kW big trolley

2t weight, 9.0m lifting height, 11.0m span, 3kW electric hoist, 0.4 kW small trolley and 20.8 kW big trolley

2t weight, 9.0 m lifting height, 11.0m span, 3kW electric hoist, 0.4 kW small trolley and 20.8 kW big trolley

10t weight, 9.0m lifting height, 16.5m span, 13kW electric hoist, 0.8 2kW small and 20.8 kW big trolley

Air (water) surge tank

Diameter of 2.0m, height 4.0 m

Diameter 3.8m , 6.0m height

Diameter of 3.8 m, 6.0m height

Leakage and Maintenance Drainage

To drain water from seepage, maintenance and rain on ramp from pump house, a sump of 2.0m (H)1.5m (W)1.8m(D)is set at left side of pump house with two movable submersible drainage pumps(1 duty and 1 standby) in. Pump outlet pipes separately extend out of house wall 0.3m

above ground and 1.0m away to an anti-scour apron.

Water Supply As required by Client, a toilet is set nearby control room, getting water through pipes after relieved by three-stage valves from pump outlet pipe

Sewage system Domestic sewage and waste water meet and drain through DN150 DICL pipe into

outdoor septic tank.

Source: Raw water supply pipeline detailed engiinering design report, Fluor group, Aug, 2008.



Page-13

22..33 EEMMEERRGGEENNCCYY SSTTOORRAAGGEE LLAAGGOOOONN

Two 200,000 m3 capacity emergency storage lagoons will be constructed on elevated ground (N

650824.56, E 4772533.64) approximately 5 km to the north of the Oyu Tolgoi site. As required,

the Lagoon storage is 400,000m3, including a 2-cell arrangement and each with a base width of 90

m and base length of 120 m.

The emergency storage lagoons will provide over a weeks water supply to the site in the event of

a major borefield / pipeline failure. This will allow sufficient time for any necessary repairs to be

made and the borefield/pipeline returned to full functionality. The emergency storage lagoons will

be constructed with earth embankments and will be completely lined with high density polyethylene

liner system in order to minimize leakage and water loss. The emergency storage lagoons will also

be completely covered by a floating cover liner in order to minimize evaporative water loss and to

prevent the undesirable accumulation of dust. The embankment design is to fully utilize the local

material. The excavation area is 55300 m2 and 5.53 ha, and if not fully utilized, disposal will be

large and the project cost will be increased. The design therefore will take measures to make the

material satisfactory to embankment and minimize disposal and soil replacement. On the basis of

safety, cost will be minimized. The embankment seepage and stability calculation has been carried

out on the basis of shear strength of rocks available in geological data, indicating the exterior slope

of 1:2.5 and interior slope of 1:3 are feasible ( 2.7

).

Photo 1. General position of the lagoon



Page-14

22..44 WWAATTEERR PPIIPPEELLIINNEE DDEESSIIGGNN

The main line of water supply pipeline totals 148.814 km, which is included delivered pipeline from

collection tank pump of 67.162 km length and pipeline of borehole connected from collection tank

pump 81.652 km length.

Under the control of the design principle, the suitable types of pipe include Ductile Iron Cement

Lined (DICL) pipe, High-Density Polyethylene (HDPE) pipe, carbon steel (CS) pipe and Fiberglass-

Reinforced Plastics (FRP) pipe.

Main pipeline diameter is different which is depends on flow rate capacity of tank pupms and the

main pipeline characteristic parameters are shown in Table 2.6 and Table 2.7.



Page-15

Table 2.6 Borehole to CTPS#1~ CTPS#5 Pipeline Parameters

Pip

e

sta

rtin

g

Pip

e e

nd

Desig

n f

low

L

/s

Calc

ula

tio

n

pre

ssu

re

b

ar

Pip

e

dia

mete

r (

)

Pip

e

mate

rial

Pip

elin

e

len

gth

m

Bo

refi

eld

are

a

GH01_PB01 C

TP

S#1

40 2.04 10 HDPE 2185

HT

zo

ne

GH01_P02 40 0.60 10 HDPE 278

GH01_PB03 40 2.76 10 HDPE 2558

GH01_PB04 40 2.16 10 HDPE 2948

GH01_PB05 40 1.32 10 HDPE 1791

GH01_PB06 40 1.56 10 HDPE 2107

GH01_PB07 40 3.24 10 HDPE 3696

GH02_PB01

CT

PS

#2

40 2.64 10 HDPE 3596

GH02_PB02 40 3.96 10 HDPE 2407

GH02_PB03 40 1.32 10 HDPE 1861

GH02_PB04 40 3.36 10 HDPE 1049

GH02_PB05 40 1.80 10 HDPE 1441

GH02_PB06 40 3.24 10 HDPE 2786

GH02_PB07 40 3.60 10 HDPE 2700

GH03_PB01

CT

PS

#3

40 1.20 10 HDPE 1393

GH03_PB02 40 4.92 10 HDPE 2503

GH03_PB03 40 2.04 10 HDPE 793

GH03_PB04 40 1.80 10 HDPE 2090

GH03_PB05 40 2.16 10 HDPE 1593

GH03_PB06 40 6.36 10 HDPE 4205

GH03_PB07 40 3.12 10 HDPE 2756

GH04_PB01

CT

PS

#4

30 1.08 10 HDPE 2429

LT

zo

ne

GH04_PB02 30 1.32 10 HDPE 3157

GH04_PB03 30 0.84 10 HDPE 1943

GH04_PB04 30 2.04 10 HDPE 2565

GH04_PB05 30 1.56 10 HDPE 2984

GH04_PB06 30 2.04 10 HDPE 4845

GH05_PB01

CT

PS

#5

30 1.32 DN200 DICL 1767

GH05_PB02 30 2.04 DN200 DICL 2577

GH05_PB03 30 1.56 DN200 DICL 1198

GH05_PB04 30 2.28 DN200 DICL 1647

GH05_PB05 30 4.32 DN200 DICL 3560

GH05_PB06 30 3.72 DN200 DICL 5086



Page-16

Table 2.7 Main pipeline parameter

Pipe starting

Pipe end

Design flow

m3/h

Design pressure

bar

Diameter of the

pipeline (mm)

Pipeline material

Length of the

pipeline

m

CTPS#1 BTPS#1 432/864/1296/1836/2376

22.8/19.2/13.2/4.32/24

DN500/DN700/DN800/DN900

DICL

31309

CTPS#2 Main pipeline 432 19.20 DN500 DICL

82

CTPS3 Main pipeline 432 13.20 DN500 DICL

111

CTPS#4 Main pipeline 540 4.32 DN400 DICL 111

CTPS#5 Main pipeline 540 24.00 DN400 DICL

111

CTPS#1 Lagoon 2376 28.20 DN900 DICL

31218

Lagoon Mine site 2376 2.00 DN900 DICL

24268

Source: Detailed design report of the industrial water supply pipeline, Flour Group, Aug, 2008.

The parameters of the these CTPS and BTPS attached in (Appendix 2.8 Collector tank pump

station CTP1 piping plan, Appendix 2.9 Collector tank pump station CTPS1 pipeline section,

Appendix 2.10 Break tank pump station BTP1 pipeline plan (Sheet 1 of 2), Appendix 2.11 Break

tank pump station BTP1 pipeline plan (Sheet 2 of 2)).

2.4.1 Pipeline cleaning

The cleaning devices (Pigging) are arranged at the main pipeline, 7 sets of pigging will be

designed for the main pipeline system.

HDPE pipe has excellent performance of stable chemical property, inherent resistance against

corrosion and scaling, strong abrasiveness, resistance against acid and alkali and low roughness.

So pipeline pigging system is not considered for the HDPE pipe.

Noted that gravity pipeline has excessive capacity to the site even with scaling and that build up

of scale doesnt impact any pumping efficiencies (as the gravity line is not pumped). As such,

pigging system is not considered to be necessary.

Pigging No.1 is installed in the DN500 pipe section near the connection with

CTPS#1 discharge pipe.







Page-17



Pigging No.5 is installed in the DN900 pipe section near the main pipe inlet to break

tank.


BTPS#1 discharge pipe.

2.4.2 CTPS#1~CTPS#5 and BTPS#1 pipeline layout

CTPS#1~CTPS#5 & BTPS#1 mainly consist of inlet flow meter pit, collector tank and pump

house. The pipeline consists of inlet pipe, overflow pip, vent pipe and outlet pipe for collector tank,

suction pipe, inlet pipe and outlet pipe for pumps, bypass (CTPS#5), compressed air pipe, diesel

oil pipe and instrument pipe.

2.4.3 Layout of lagoon

Lagoon mainly consists of inlet flow meter pit, inlet valve pit, storage pond, outlet valve pit, outlet

flow meter pit, intake and outlet. The pipeline consists of inlet pipe, outlet pipe, bypass and

instrument pipe.

2.4.4 Pipeline protection

High density polyethylene (HDPE) and ductile iron cement lied (DICL) pipes have been selcted for

use due to having high internal and external corrosion resistance. In extreme cases, (for example

at river crossing), additional corrosion protection will be applied to DICL pipes. Engineering

geological investigation analysis shows the amount of mineral substances in the gravel, sand and

clay soils is extremely high. However because of the generally low moisture barrier is sufficient

protection for most of the pipelines.

Common practice in Mongolia for basic corrosion protection for steel pipe involves outside coating

with a layer of bitumen of 3 mm thick and wrapping by one layer of synthetic film or brizol (ruberoid

film coated with bitumen). The strenghtened protection involves coating by two layers of bitumen

and two layers of wrapping by ruberoid containing brizol or bitumen. There are other wrapping

products used outside Mongolian that may be more effective and these should be compared with

the local methods for cost-effectiveness.

It is also important to route high-voltage power lines away from the steel pipelines to avoid inducing

currents that will promote corrosion.



Page-18

2.4.5 Pipeline excavation and backfill

Trench digging and backfilling should be done in accordance with Mongolian standards. The

standard state that potable water pipelibes without insulation shall be installed at a minimum depth

of 0.5 m below freezing level which, based on the stated freezing depth of 1.5 m to 2.2 m, would

require that the top of the pipe be placed at a minimum depth of 2.2 m to 2.7 m depth beneath

natural surface. With pipe diameters up to 900 mm diameter plus bedding material, trench depth

can easily reach 4.0 m. Freezing depth for different soils in accordance with Mongolian norms are

presented in the Table below (Appendix 2.12 Pipeline typical cross sections).

Table 2.8 Excavation Depth for Pipe Trenches

Nominal diameter

Trench width (m ) Records

10 2.75 Pipeline between bore pump and

CTPS#1CTPS#5

DN400 2.65 Main pipe


DN700 2.6 Main pipe



The finally adopted trench slope shall be determined based on type of soil and depth of trench and

will be finalised in the detailed design phase. The current proposed trench slopes are illustrated in

the Table below.

Table 2.9 Trench slope versus soil types and depths

Soil type Trench depths, m

0,0 3,0 3,0 6,0

Sand and gravel 1:1.25 1:1.25

Sandy clay 1:0.67 1:1

Clay 1:0.5 1:0.67

Note: Slopes shown are to read as Ver : Hor

The minimum width at the base of the trench shall be at least the outside diameter of the pipe plus

a minimum of 0.5 m. Where the pipe diameter exceeds DN700 mm, the trench width should be a

minimum of 1.5 times the diameter of pipe (i.e. 1.5 DN) as illustrated below. However, in

estimating the extent of the trench excavation and costs, it has been assumed that an excavator

with a 1.25 m wide bucket will be used to excavate the trench, and for practical proposes this is

has been taken as the minimum bottom width of the trench.



Page-19

2.4.6 Pipeline thrust block

Hydraulic thrust forces occur at changes in direction, reductions in diameter (bends, tees and

tapers) and at the ends of pipelines carrying water under pressures. They can be high and must be

counterbalanced by appropriate self-anchored joint systems or by anchor blocks. According to the

arrangement design of main pipeline, the following typical pipe section should be protected by

thrust block.

1. Unburied pipe at the turn in the pump house.

2. Ductile iron pipe with socket and spigot connection at the vertical bend, horizontal bend, T-

shaped pipe and pipe block.

3. Fiberglass-Reinforced Plastic (FBR) pipe with socket and spigot connection at the vertical

bend.

When the hydraulic thrust forces in the pipe is beyond the force endured by the pipe itself, the

thrust block should be considered.

22..55 IINNFFRRAASSTTRRUUCCTTUURREE RREEQQUUIIRREEMMEENNTTSS

2.5.1 Fire safety

With reference to geographic location and project features, fire safety approaches are selected

based on functions of different rooms in CTPS#1~CTPS#5 and BTPS#1. At present, both propane

heptafluoride gas no-pipe devices (propane devices) and portable fire extinguishers are used in

control room, electrical room, diesel generator room and oil tank room of CTPS#1 to CTPS#5,

BTPS#1 and control room of Lagoon, and only portable fire extinguishers are used in bore pump

houses and operators room at Lagoon.

2.5.2 Heating, Ventilation and air conditioning system

Water pipeline and water pump are arranged in CTP, CTP#1~CTP#5 and BTPS#1, Indoor

temperature shall be maintained within the range specified in codes while water pump working or

water pump in shutdown in winter. A set of air conditioner is installed at the electric room with

different cooling capacity for use in summer. Air conditioner is started once temperature is higher

than 38C, and stop once lower than 28C. Heating, Ventilation, and Air Contioning Design

Considerations for BPS, CTPS and BTPS are listed in Table 2.10.



Page-20

Table 2.10 Heating, Ventilation, and Air Contioning Design Considerations for BPS, CTPS and BTPS

Parameters Bore Pump

Station CTPS#1 BTPS#1

Hot-

pla

tes

Indoor temperature +5C +5C +5C

Started once temperature

lower than +5C lower than +5C lower than +5C

Stop once temperature higher than +15C higher than +8C higher than +8C

Far infrared hot-plates eight 2000 W far infrared hot-plates

three 2000 W far infrared hot-plates

three 2000 W far infrared hot-plates

Air c

onditio

ner

at

the e

lectr

ical

room

Heat generation of electrical equipment

4 kW 4 kW 4 kW

Cooling capacity 6000 kW 14000 kW 100000 kW


higher than +38C higher than +38C higher than +38C

Stop once temperature lower than +28C lower than +28C lower than +28C

Air c

onditio

ner

at

the e

lectr

ical

room

Cooling capacity 7000 kW 7000 kW


higher than +38C higher than +38C

Stop once temperature lower than +28C lower than +28C

Water pipe 6 cm of exceed thin glass cotton

6 cm of exceed thin glass cotton

6 cm of exceed thin glass cotton

2.5.3 Power supply

The 35kV power supply which comes from the mine through the overhead line serves every BPS,

CTPS#1, CTPS#2, CTPS#3, CTPS#4, CTPS#5, BTPS#1, and Lagoon. A 35KV substation is set at

the pump station to step down the voltage to 6KV and connects every BPS, CTPS#1-CTPS#5,

BTPS#1 and Lagoon through cables.

The 6KV overhead line connects the nearby CTPS#1-CTPS#5 to each Bore Pump Station (all 33),

and a 6KV outdoor transformer stepping down to 0.4KV is set at each Bore Pump Station.

2.5.4 Design of distributed control system

The DCS is arranged for the whole OT water supply system, which consists of the remote control

layer within the WCC, the control layer of pump station, local control station and network

equipment, installed respectively in each CTPS#1~CTPS#5, BTPS#1 and Lagoon under VFD

(Variable Frequency Drives) to regulate flow rate. The VFD communicates with the DCS through

Profibus DP to realize automatic control of the pipeline system. The DCS takes signal

measurement of flow, pressure, temperature, leakage, etc. at key positions of the pipeline, and

enables local display and remote transmission.

The DCS for the pump station is open and distribution system with flexible configuration and

convenient functional pattern. The local control station, as the LCU (Local Control Unit) of the



Page-21

motor, is distributed in each pump house, and collects the status signal of the motor, enables auto-

control of the pump and remote signal transmission.

The connection between every control layer of pump station is carried out through Ethernet in

exchange at a speed of 100Mbps in conformity with TCP/IP. The communication means of either

wireless (e.g. microwave) or optical cable are to be determined by PMT.

2.5.5 Design of security system

Security system is composed of three sub-systems:

Fire alarm,

CCTV system,

Security and access control.

Fire alarm: With reference to the building layout in the basic design and specifications, an

area fire alarm control is set in each of BPS, CTPS#1~CTPS#5, BTPS#1, and Lagoon,

totally 40 of such controls, which connects with the communication device of the pump

station supplied by others through the Ethernet interface. The dot-type smoke detector and

dot-type temperature detector is placed on the roof of the each BPS.

CCTV system: A set-up of this system is isatalled each construction. Two cameras are set

at each of the bore pump stations, totally 66. Four CCTV cameras are set in each of

CTPS#1~CTPS#5, totally 20 cameras. CCTV cameras are set at BTPS#1, totally five

cameras. The totally five cameras are set at Lagoon.

Security and access control: All rooms of the above buildings are set with passive

infrared detector, and the access switch is set at the entrance of pump and main room. The

active infrared detector is set at the walls around the building. All detection signals are

received by the main security control in the pump station and then interface with the

communication device supplied by others.

2.5.6 Maintenance road

The main line of maintenance roads totals 67.105 km, and the line of totally 30 branch roads is

75.596 km long. The design of maintenance roads considers the low frequency of traffic and small

load. According to the geotechnical data along the pipeline, the plane curve, vertical curve and

turning radius all follow the requirements of Mongolian design codes. The pavement structural

design is based on truck-20t load, including the road surface width of 4.5 m, shoulder width of 1m

at both cut and fill sections, and the road surface is of graded gravel pavement. Roads across the

river are specially designed with concrete pavement. Fill sections will borrow materials from the



Page-22

nearby area, and for pure sand sections, materials will be cut and transported from the specialized

borrow area.

The design of maintenance roads includes minimum horizontal curvature radius of 100m, minimum

vertical curve of 1000m and maximum slope of 5.7%. The alignment has been modified to ensue

that there are minimal crossing of watercourses and where these occur, there will be requirements

for culvert / floodway type crossing at these points.

All road construction material will be won from local sources along the route with the best quality

material being used for the wearing course and the lower quality material utilized as base course.

Figure 2.1 Maintenance road design

22..66 WWAATTEERR QQUUAALLIITTYY

The raw water quality of the Gunii Hooloi borefield may be characterized as:

1. Relatively high salinity;

2. A high degree of hardness;

3. Relatively high pH and alkalinity;

4. Relatively low in iron; and

5. Does not present any significant bacteriological contamination.

It is anticipated that the water will fall in temperature from the approximately insitu temperature of

15C in the aquifer to a temperature of 2C at the delivery point at the end of the main pipeline

during winter. It is highly undesirable to treat the water in dispersed bore field. At most, chemical

dosing is sometimes used to control scaling or corrosivity in the collector main pipelines.

Section Groundwater will be included about it more comprehensive.



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3.0 ENVIRONMENTAL IMPACTS ASSESSMENT OF THE PROJECT

This assessment was conducted in accordance with law on Environmental Impacts Assessment

and in coordination with methodological instruction on conducting detailed environmental impact

assessment indicated in attachment three of order N 119 issued by Minister of Environment in April

27, 2006. They include establishment of water supply pipelines from Oyu Tolgoi and Gunii Hooloi

phreatic water resources; main environmental impacts on nature when water supply is closed;

movements of vehicles and equipments used for constructing and utilizing the water supply; noise

caused by engines used in facilities, and; damage and soil degredation and vegetation.

Detailed environmental baseline research of areas where the project is planned to implement

including Oyu Tolgoi deposit, Galbyn Gobi and Gunii Hooloi has been conducted by environmental

impact assessment experts of Eco Trade Company since 2002. Therefore detailed report on

assessment was developed and some information and data from the report are used in the present

report.

Please refer to following documents for more detailed information: Detailed Environmental Impact

Assessment of Oyu Tolgoi project- Volume III: Mining and Processing, Detailed Environmental

Impact Assessment of Oyu Tolgoi project Groundwater Resource Use from Gunii Hooloi and

Galbyn Gobi Regional Aquifers-Volume II, Environmental baseline report, 2003 , Environmental

Baseline Report of Oyu Tolgoi project, 2003 prepared by Eco Trade LLC.

33..11 MMEETTHHOODDOOLLOOGGYY OOFF AASSSSEESSSSMMEENNTT

When we assessed environmental impacts of Oyu Tolgoi water supply pipeline project we used

matrix method with 5 stages and then we consolidated how much was the impact of water supply

pipeline project for the area. Finally we combined all impacts for each certain area to make one

general conclusion. We have assessed the extent of impacts to the environment and their

probability using the expert matrix method with 5 stages and 25 categories. A summary

considering the main results of impacts regarding each object affected negatively is as follows:



Page-24

Figure 3.1 Expert assessment matrix

Impacts

Magnitude and extent of impact

Insignificant Low Moderate High Extreme

Probability

High :

given or certain

or currently

occurring

Moderate Moderate High High High

Probable or

likely:

re-occurrence

interval of less 1

month

Low Moderate Moderate High High

Possible:

re-occurrence

interval of 1

month to 2

years

No impact Low Moderate High High

Unusual or

unlikely:

re-occurrence

interval of 2 to

10 years

No impact No impact Low Moderate High

Rare:

re-occurrence

interval of >10

years

No impact No impact Low Moderate Moderate

Assessing certain risk in coordination with intensity, extent and probability of negative

environmental impact corresponded with reality more and it was helpful to design and work out the

environmental protection plan and environmental analysis and monitoring program. For instance, in

the occurrence of certain risk, if negative impact is medium and extent is little while probability is

high, this risk or negative impact is included in the high risk category which requires us to pay more

attention on risk preventive measures.

We analyzed intensity and probability of each environmental impact by the following methods:

collecting data, analyzing the collected data and simulating the impact through mathematical

modeling.



Page-25

33..22 MMAAIINN AASSSSEESSSSMMEENNTT MMEETTHHOODDSS

Fundamental environmental research Current condition of environment (it includes: climate, air

quality, geography, landscape, geology, surface and internal water, soil and subsoil, flora and

fauna) and cultural heritage research were conducted based on field research material, data and

monitoring data done in June 2007. Additionally we used data from the following reports: Detailed

Environmental Impact Assessment of the Oyu Tolgoi Project Mining and Processing - Volume III

and Detailed Environmental Impact Assessment of the Oyu Tolgoi Project Groundwater Resource

Use from Gunii Hooloi and Galbyn Gobi Groundwater Regional Aquifer-Volume II.

The assessment on impact to the quality of the environment involved analysis of data and

compiling summaries based on fundamental research on the current condition of environment

using the method of matrix according to assessment requirements.

Probable negative impacts to environment were estimated based on modeling, standard analysis

and estimation. Management and mitigation measures are presented in this report to address the

predicted negative impacts.

4.0 CLIMATE

44..11 CCHHAARRAACCTTEERRIISSTTIICCSS OOFF CCLLIIMMAATTEE

Internal water resource area of Gunii Hooloi is located 40-60 km away north east of Oyu Tolgoi

deposit. It borders with mountain Khanbogd the east and with Galbyn Gobi on the northeast which

creates very large valley. As for climate, it is same as climate of areas of Khanbogd and Oyu

Tolgoi. Location of the meteorological stations around the project area is included in Appendix 4.1.

Eco Trade Company developed main climate indicators of Oyu Tolgoi and surrounding areas

based on long term data collected at meteorological stations of Khanbogd and Bayan-Ovoo sums

and data collected at meteorological station established at Oyu Tolgoi project area in 2002. The

collected information was included in report Detailed Environmental Impact Assessment of Oyu

Tolgoi project Mining and Processing - Section III by Eco Trade LLC completed in 2006.

To examine the climate characteristics:

Generally there is high temperature fluctuation at Oyu Tolgoi and surrounding areas depending on

day, night and season. Therefore the extreme temperature varies between -350 and +380 which

has severe continental climate characteristics. The number of warm days which temperature is

over +300 reaches 120-140 days per year, and number of warm days per year which temperature

is over 00 ranges between 210 and 232 days.

Average annual temperature is 6.9C, and annual temperature difference is 50.6C in average.

Highest average temperature of many years reaches 30.9C (average of July), average minimum

temperature reaches -19.7C (average of January). Daily average temperature fluctuation is

Oyu Tolgoi project

Documents

Detailed EIA Oyu Tolgoi Project Water Supply Pipeline 2009 En