ENVIRONMENTAL AND SOCIAL IMPACTASSESSMENT

PHU THO PROVINCIAL PEOPLE’S COMMITTEEPHU THO PROJECT MANAGEMENT UNIT OF CONSTRUCTION INVESTMENT WORKS FOR AGRICULTURE AND RURAL DEVELOPMENT ---REPORT ENVIRONMENTAL AND SOCIAL IMPACT ASS

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PHU THO PROVINCIAL PEOPLE’S COMMITTEE

PHU THO PROJECT MANAGEMENT UNIT OF CONSTRUCTION INVESTMENT WORKS FOR AGRICULTURE AND RURAL

DEVELOPMENT

-REPORT ENVIRONMENTAL AND SOCIAL IMPACT

ASSESSMENT

SUBPROJECT: DAM REHABILITATION AND SAFETY IMPROVEMENT (WB8)

PHU THO PROVINCE PROJECT: DAM REHABILITATION AND SAFETY IMPROVEMENT

(DRSIP/WB8) FUNDED BY THE WORLD BANK

Phu Tho, August 2019

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PHU THO PROVINCIAL PEOPLE’S COMMITTEE

PHU THO PROJECT MANAGEMENT UNIT OF CONSTRUCTION

INVESTMENT WORKS FOR AGRICULTURE AND RURAL

DEVELOPMENT

-REPORT ENVIRONMENTAL AND SOCIAL IMPACT

ASSESSMENT

SUBPROJECT: DAM REHABILITATION AND SAFETY IMPROVEMENT (WB8)

PHU THO PROVINCE PROJECT: DAM REHABILITATION AND SAFETY IMPROVEMENT

(DRSIP/WB8) FUNDED BY THE WORLD BANK

REPRESENTATIVE OF THE PROJECT

OWNER: PHU THO PROJECT

MANAGEMENT UNIT OF CONSTRUCTION

INVESTMENT WORKS FOR AGRICULTURE

AND RURAL DEVELOPMENT

REPRESENTATIVE OF THE CONSULTANCY UNIT: THANG LONG INFRASTRUCTURE TECHNOLOGY CONSTRUCTION CONSULTANT JOINT STOCK COMPANY

Phu Tho, August 2019

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LIST OF ABBREVIATIONS

AH Affected Household

CPC Communal People’s Committee

CPO Central Project Office

DPC District People’s Committee

DSR Dam Safety Report

DRSIP Dam Rehabilitation and safety improvement

DED Detailed Engineering Design

ECOP Environmental Codes of Practice

SA Social Assessment

EIA Environment Impact Assessment

ESMF Environment and Social Management Framework

EMDF Ethnic Minority Development Framework

EMDP Ethnic minority Development Plan

EM Ethnic minority

EMP Environement Management Framework

ESIA Environement and Social Impact Assessment

ESMP Environement and Social Management Plan

FPIC Free, prior and informed consent

IPM Integrated Pest Management

ICM Integrated Crop Management

MARD Ministry of Agriculture and Rural Development

MCM Million Cubic Meters

MoIT Ministry of Industry and Trade

MoNRE Ministry of Natural Resources and Environment

WB World Bank

FFS Farm Field School

O&M Operation and Maintenance

OP/BP Operational Policy and Bank Procedures

GAP Gender Action Plan

IDA International Development Agency

RAP Resettlement Action Plan

PPMU Provincial People’s Committee

PMU Project Management Unit

PMB Project Management Board

PoE Panel of Experts

PPMU Provincial Project Management Unit

PSC Project Steering Committee

SRI System Rice Intensification

TOF Training of farmers

VND Vietnamese dong

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TOR Terms of Reference

UNDP United Nations Development Program

WHO World Health Organization

WUA

UXO

Water Users AssociationUnexploded ordnance

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TABLE OF CONTENT

LIST OF TABLES 7

LIST OF FIGURES 10

SUMMARY 11

CHAPTER I: PROJECT INTRODUCTION 17

1.1 Overview of the project 17

1.2 Approaches and methodologies 18

(1) Rapid assessment method 18

(2) The method of building impact matrix 19

(3) Comparative method 19

(4) Description of environmental system 19

(5) Enumerating method 19

(6) System analysis method 19

(7) Community consultation method 19

(8) Method of collection and analysis of information and data 19

(9) Field survey method 19

(10) Expert method 20

(11) Method of sampling and analysis in laboratory 20

1.3 Implementation arrangement of ESIA report 20

CHAPTER II: DESCRIPTION OF SUBPROJECT 22

1.4 Overview of the subproject 22

1.5 Status of works and construction solutions 24

1.6 Summary of excavation volume, construction materials and machinery 53

1.7 Auxiliary items 60

1.8 Material transportation plan 63

1.9 Pre-construction activities 63

1.10 Operational and maintenance activities 63

1.11 Dam safety plan 64

1.12 Subproject implementation schedule 65

1.13 Cost of implementation 65

CHAPTER 3: POLICY, LEGAL AND ADMINISTRATIVE FRAMEWORK 66

1.14 Government Regulations 66

1.15 The World Bank’s safeguard policies 69

CHAPTER 4: NATURAL, SOCIO-ECONOMIC CONDITIONS AND ENVIRONMENTAL STATUS 76

1.16 Natural conditions 76

1.17 Status of Natural environmental situation 87

1.18 General socio-economic characteristics of sub-project areas 108

1.19 Site specific impacts 135

CHAPTER 5: ENVIRONMENTAL AND SOCIAL IMPACT ASSESSMENT .140 1.20 Types and scale of impacts 140

1.21 Positive environment and social impacts 141

1.22 Potential negative impacts from the subproject on the social environment 142

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5.4 Analysis of types of impact 189

CHAPTER VI: ALTERNATIVE ANALYSIS 191

6.1 Without subproject 191

6.2 With sub-project 192

CHAPTER VII: ENVIRONMENTAL AND SOCIAL MANAGEMENT PLAN (ESMP) 194

7.1 Objectives 194

7.2 Mitigation measures 195

7.3 Implementation arrangement 235

7.4 Environmental Compliance Framework 241

7.4.1 Environmental tasks of the Contractor: 241

7.4.2 Contractor’s safety, social and environmental officer 242

7.4.3 Social and environmental monitoring during construction phase (Monitoring Consultant) 242

7.4.4 Compliance with contract requirement and legal regulations 243

7.4.5 Report System 243

7.5 Grievance redressing mechanism 244

7.5.1 Complaint settlement procedures 244

7.5.2 Contractor and construction supervision consultant: 245

7.5.3 Grievance redressing mechanism of the WB 246

7.6 ESMP Implementation plan 246

7.6.1 ESMP Implementation Plan of the Contractor 246

7.6.2 Subproject commencement and personnel 246

7.7 Capacity development and training plan 247

7.7.1 Training on safeguard policies 247

7.7.2 Occupational health and safety training 247

7.7.3 Orientation of visitors 247

7.7.4 Training for new contractors and workers 247

7.7.5 Basic training on occupational health and safety 247

7.8 Environmental quality monitoring plan 248

7.9 Estimated cost 250

CHAPTER VIII: PUBLIC CONSULTATION AND INFORMATION DISCLOSURE 256

8.1 Community consultation 256

8.2 Information Disclosure 265

CONCLUSIONS AND RECOMMENDATIONS 266

REFERENCES 267

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LIST OF TABLES

TABLE 1: THE LIST OF RESERVOIRS UNDER THE SUBPROJECT OF “DAM REHABILITATION AND SAFETY IMPROVEMENT (WB8), PHU THO PROVINCE” 11 TABLE 2: COST ESTIMATE FOR ESMP IMPLEMENTATION 15 TABLE 3: LIST OF PERSONS PARTICIPATING IN IMPLEMENTATION 20 TABLE 4: GEOGRAPHIC LOCATION OF RESERVOIR UNDER THE SUBPROJECT 22 TABLE 5: : SUMMARY OF CURRENT INFORMATION OF RESERVOIRS AND CONSTRUCTION WORKS OF THE SUBPROJECT 24 TABLE 6: VOLUME OF EXCAVATION SOIL 53 TABLE 7: VOLUME OF CONSTRUCTION MATERIALS 53 TABLE 8: FORECAST OF OIL CONSUMPTION IN CONSTRUCTION ACTIVITIES AT CONSTRUCTION SITES 53 TABLE 9: LIST OF MACHINES AND EQUIPMENT FOR CONSTRUCTION OF SUBPROJECT WORKS 54 TABLE 10: DISTANCE, TRANSPORT ROUTE OF MATERIALS 56 TABLE 11: EXPECTED NUMBER OF WORKERS IN CONSTRUCTION SITES 60 TABLE 12: PLANNING MATERIAL MINES OF NUI DAU RESERVOIR 61 TABLE 13: PLANNING MATERIAL MINES OF DOC GAO VÀ SU RESERVOIR 62 TABLE14: VOLUME OF DISPOSAL AND LOCATION OF LANDFILL OF THE SUBPROJECT 62 BẢNG 15: COST OF IMPLEMENTATION 65 TABLE 16: SUMMARY OF ENVIRONMENTAL ASSESSMENT PROCESS OF

WB & GOVERNMENT 72 TABLE17: THE AVERAGE AIR TEMPERATURE FOR MANY YEARS 84 TABLE 18: AVERAGE AIR HUMIDITY FOR MANY YEARS 84 TABLE 19: AVERAGE NUMBER OF SUNSHINE HOURS IN MONTHS OF THE YEAR 84 TABLE 20: AVERAGE WIND SPEED IN MONTHS AND YEARS 85 TABLE 21: MAXIMUM WIND SPEED IN DIRECTION AND EXCLUDING DIRECTION, P% 85 TABLE 22: DISTRIBUTE PICHE EVAPORATION AND EVAPORATE WATER 85 TABLE 23: AVERAGE ANNUAL RAINFALL IN MANY YEARS IN RESERVOIR BASINS 86 TABLE 24: FLOW OF DESIGNED FLOOD PEAKS (MAIN SEASON) 86 TABLE 25: SAMPLING LOCATION, MEASUREMENT OF ENVIRONMENTAL QUALITY IN THE SUBPROJECT AREA 87 TABLE 26: RESULTS OF ANALYSIS OF AIR QUALITY AND NOISE IN THE SUBPROJECT AREA 91 TABLE 27: RESULTS OF ANALYZING SURFACE WATER QUALITY IN THE SUBPROJECT AREA 94 TABLE 28: RESULTS OF ANALYSIS OF GROUNDWATER QUALITY IN THE SUBPROJECT AREA 99

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TABLE 29: RESULTS OF SOIL ENVIRONMENT QUALITY ANALYSIS IN THE

SUBPROJECT AREA 103

TABLE 30: DETAILS ON SOCIO-ECONOMIC CONDITIONS OF SUBPROJECT COMMUNES 115

TABLE 31: ETHNIC MINORITY STRUCTURE OF THE SUBPROJECT COMMUNES 118

TABLE 32: GENDER OF THE RESPONDENTS 119

TABLE 33: AGE OF RESPONDENTS 120

TABLE 34: SIZE OF SURVEYED HOUSEHOLDS 120

TABLE 35: ETHNICITY OF RESPONDENTS 121

TABLE 36: EDUCATION OF RESPONDENTS 122

TABLE 37: OCCUPATION OF RESPONDENTS 123

TABLE 38: LEVEL OF INCOME OF SURVEYED HOUSEHOLDS 124

TABLE 39: EXPENDITURE OF HOUSEHOLD BY PROJECT COMMUNES 125 TABLE 40: TYPE OF HOUSES 126

TABLE 41: RESIDENTIAL AND AGRICULTURAL LAND OWNER OF HOUSEHOLD 127

TABLE 42: ASSETS OF HOUSEHOLD 127

TABLE 43: SUMMARY OF AVERAGE LAND AREA OF HOUSEHOLD 128

TABLE 44: INCOME SOURCE OF HOUSEHOLDS 129

TABLE 45: THE NEED TO SUPPORT FOR HOUSEHOLD 130

TABLE 46: SOURCE OF DOMESTIC WATER OF SURVEYED HOUSEHOLD 130

TABLE 47: WATER SOURCE FOR DOMESTIC AND PRODUCTION PURPOSES OF HOUSEHOLD 131

TABLE 48: TYPE OF TOILET OF HOUSEHOLD IN THE PROJECT COMMUNES 132

TABLE 49: ASSESSMENT ON SOCIAL SERVICES IN THE LAST 3 YEARS 133

TABLE 50: NATURAL DISASTERS AND EPIDEMIC IN THE LAST 3 YEARS 133

TABLE 51: VULNERABLE HOUSEHOLD INFORMATION OF PROJECT AREA 134

TABLE 52: SUMMARY OF THE STATUS OF SENSITIVE WORKS 135

TABLE 53: THE CRITERIA FOR CLASSIFICATION OF NEGATIVE IMPACTS 140

TABLE 54: SOURCES OF IMPACT DURING CONSTRUCTION PREPARATION PHASE 142

TABLE 55: LAND AREA IS PERMANENTLY ACQUIRED ACCORDING TO EACH SUB-PROJECT ITEM 144

TABLE 56: SUMMARY ABOUT NUMBER OF HOUSEHOLDS AFFECTED WITH STRUCTURES 145

TABLE 57: SUMMARY OF AFFECTED TREES AND CROPS 145

TABLE 58: THE VOLUME OF BIOMASS GENERATED DURING THE PREPARATION PHASE 148

TABLE 59: GEOLOGICAL DRILLING VOLUME OF THE SUBPROJECT 149

BẢNG 60: SUMMARY OF SOURCE OF IMPACT DURING CONSTRUCTION PHASE 150 TABLE 61: SUMMARY OF MATERIAL VOLUME FOR PROJECT AND

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VOLUME EXCAVATION OF SOIL AND EMBANKMENT 153 TABLE 62: CONCENTRATION POLLUTANTS IN THE AIR FROM THE PROCESS OF TRANSPORTING CONSTRUCTION MATERIALS ARE SWEPT WITH THE WIND 154 TABLE 63: POLLUTANT LOAD COEFFICIENT FOR TRUCKS RUNNING ON ROADS (FOR 1000 KM) 155 TABLE 64: NUMBER OF TURNS TRANSPORT VEHICLES 155 TABLE 65: CONCENTRATION OF POLLUTANTS THROUGH TRANSPORT

OF MATERIALS 156 TABLE 66: POLLUTION EMISSION COEFFICIENT DUE TO CONSTRUCTION ACTIVITIES 158 TABLE 67: CONCENTRATION OF POLLUTANTS THROUGH EARTHWORKS 158 TABLE 68: CONCENTRATION OF POLLUTANTS FROM THE OPERATION

OF CONSTRUCTION MACHINERY 159 TABLE 69: ESTIMATES OF SOURCES OF SUBSTANCES CAUSING WATER CONTAMINANTS 161 TABLE 70: EMISSION FACTOR OF POLLUTANTS OF DOMESTIC WASTEWATER DURING CONSTRUCTION PHASE 161 TABLE 71: THE LOADING OF POLLUTANT LOAD OF DOMESTIC WASTEWATER DURING CONSTRUCTION PHASE FOR RESERVOIRS: DA DEN; NHA GIAC; DAM GAI; VO RESERVOIR; BA GAC; CAY QUYT; DOC HEP;

SU RESERVOIR; VINH LAI 162 BẢNG 72: THE LOADING OF POLLUTANT LOAD OF DOMESTIC WASTEWATER DURING CONSTRUCTION PHASE FOR RESERVOIRS: NUI DAU 162 BẢNG 73: THE LOADING OF POLLUTANT LOAD OF DOMESTIC WASTEWATER DURING CONSTRUCTION PHASE FOR RESERVOIRS: DOC GAO; DAT DOI 163 BẢNG 74: THE LOADING OF POLLUTANT LOAD OF DOMESTIC WASTEWATER DURING CONSTRUCTION PHASE FOR RESERVOIRS: TRAM SAT 163 TABLE 75: CONCENTRATION OF POLLUTANTS OF DOMESTIC WASTEWATER DURING CONSTRUCTION PHASE 163 TABLE 76: CONCENTRATION OF POLLUTANTS IN CONSTRUCTION WASTE WATER 164 TABLE 77: PREDICT POTENTIAL SOIL EROSION DUE TO RAIN FROM CONSTRUCTION ITEMS OF THE SUBPROJECT 165 TABLE 78: FLOW AND LOAD OF POLLUTANTS IN WASTEWATER FROM CONSTRUCTION EQUIPMENT 166 TABLE 79: RESULTS OF CALCULATION OF DOMESTIC SOLID WASTE VOLUME IN SUBPROJECT CONSTRUCTION 167 TABLE 80: RESULTS OF CALCULATING THE VOLUME OF BIODEGRADABLE ORGANIC MATTER 167 TABLE 81: RESULTS OF CALCULATING INORGANIC MASS AND ORGANIC MATTER ARE DIFFICULT TO DECOMPOSE 168 TABLE 82: FORECAST RESULTS OF HAZARDOUS WASTE GENERATED FROM BASIC CONSTRUCTION ACTIVITIES ON 1 CONSTRUCTION 171 TABLE 83: CALCULATION RESULTS OF NOISE LEVEL AT SOURCE DURING CONSTRUCTION PHASE 172 TABLE 84: FORECAST OF NOISE REDUCTION ACCORDING TO DISTANCE

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FROM SOURCE 173

TABLE 85: VIBRATION LEVEL DECREASES WITH THE DISTANCE IN CONSTRUCTION 174

TABLE 86: POTENTIAL IMPACTS DURING CONSTRUCTION IMPLEMENTATION TO SENSITIVE WORKS 183

TABLE 87: COST ESTIMATE FOR COMPENSATION AND RESETTLEMENT 196

TABLE 88: ENVIRONMENTAL CODE OF PRACTICES (ECOP) TO MITIGATE GENERAL IMPACTS DURING THE CONSTRUCTION PROCESS 203

TABLE 89: EMDP IMPLEMENTATION PLAN 224

TABLE 90: COSTS IMPLEMENTATION OF EMDP 225

TABLE 91: MITIGATION MEASURES FOR SENSITIVE WORKS 226

TABLE 92: GENERAL MITIGATION MEASURES FOR IMPACTS DURING OPERATION PHASE 234

TABLE 93: ROLES AND RESPONSIBILITIES OF STAKEHOLDERS 237

TABLE 94: REQUIREMENTS ON REPORT SYSTEM 243

TABLE 95: : SUMMARY OF THE CONTENTS OF QUALITY MONITORING OF ENVIRONMENTAL COMPONENTS IN THE CONSTRUCTION PHASE AND OPERATION AND MAINTENANCE 249

TABLE 96: ESTIMATED COSTS FOR ESMP 250

TABLE 97: BUDGET SOURCE FOR ESMP MONITORING 251

TABLE 98: SUMMARY OF MITIGATION MEASURES 252

TABLE 99: SUMMARY OF PARTICIPANTS IN THE CONSULTATION MEETINGS 256

TABLE 100: COMMENTS OF PEOPLE'S COMMITTEES OF COMMUNES UNDER THE SUBPROJECT 257

TABLE 101: SUMMARY OF CONSULTATION RESULTS AND REPLY OF THE PROJECT OWNER 262

LIST OF FIGURES FIGURE 1: LOCATIONS OF SUBPROJECT RESERVOIRS 23

FIGURE 2: GEOGRAPHICAL LOCATION OF PHU THO PROVINCE 76

FIGURE 3: LOCATION OF THE SUBPROJECT AREA ON THE GEOLOGICAL MAP 78

FIGURE 4: STRUCTURE OF ENVIRONMENTAL MANAGEMENT AND SUPERVISION ORGANIZATION 236

FIGURE 5: ORGANIZATIONAL CHART OF SUBPROJECT SAFEGUARD PERFORMANCE 236

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1 Introduction: The project of: “Dam Rehabilitation and Safety Improvement (DRSIP/WB8)

funded by the World Bank is approved by Prime Minister in accordance with the Decision No.1858/QĐ-TTg dated 02/11/2015 and the Feasibility Study Report of the project is approved byMinister of Ministry of Agriculture and Rural Development through Decision No 4638/QĐ-NN-HĐQT dated 09/11/2015

2 Subproject: Dam rehabilitation and safety improvement in Phu Tho province under the project ofdam rehabilitation and safety improvement, WB8 Contract No 53/HDTV dated July 19, 2018between the Phu Tho project management unit of construction investment works for agriculture andrural development and Irrigation Construction Consultant Joint Stock Company II on Surveying andmaking feasibility study reports and dam safety reports for the Subproject: dam rehabilitation andsafety improvement (wb8) Phu Tho province belong Project dam rehabilitation and safetyimprovement (WB8) Subproject: dam rehabilitation and safety improvement (WB8) Phu Thoprovince include the works follow:

Table 1: The list of reservoirs under the subproject of “Dam rehabilitation and Safety Improvement

(WB8), Phu Tho province”

No reservoirs Name of Construction site Height of dam (m) Capacity (x10 6 m 3 )

1 Da Den Yen Kien commune, Doan Hung district 8.9 0.32

2 Nha Giac Van Du commune, Doan Hung district 8.5 0.6

3 Nui Dau Ngoc Quan commune, Doan Hung district 10.3 0.39

4 Dam Gai Luong Nha commune, Thanh Son district 7.5 1.8

5 Tram Sat Do Son commune, Thanh Ba district 7.0 1.1

6 Vo Luong Son commune, Yen Lap district 10.0 0.35

7 Dat Doi Phuong Vi commune, Cam Khe district 17.0 0.22

8 Ba Gac Ninh Dan commune, Thanh Ba district 14.0 0.85

9 Cay Quyt Hau Bong commune, Ha Hoa district 5.0 0.2

10 Doc Hep Dao Xa commune, Thanh Thuy district 4.4 0.2

11 Su Tan Phuong commune, Thanh Thuy district 5.0 0.5

12 Doc Gao Dieu Luong commune, Cam Khe district 8.0 1.78

13 Vinh Lai Hung Quan commune, Doan Hung district 5.0 0.2

3 The status of reservoirs under the subproject: The reservoirs of subproject were built and put

into operation for a long time Currently the earth dam has been seriously degraded, small dam face,low, high, rugged and the dam surface has not been reinforced with concrete Embankment soil ofdams previously inferior quality, constructed mannually, therefore, there are some leakage positions onthe body of the dams and the adjoining contiguous between the dam and the foundation Protecting theupstream roof with freestone has been eroded and damaged in many places, some reservoirs have notbeen reinforced and protected The grass in the downstream slope is heavily eroded, most reservoirs donot have downstream drainage facilities/equipment On the other hand, flood spillways of reservoirsare mainly constructed by soil, that has been erosion and damaged, there is no bridge over floodspillways position to serve people traveling (Only some reservoirs have been repaired) According tothe original design documents, the flood protection design level P = 1.5%, 2% Recently due to climatechange, flooding is being bigger and faster because of deforestation, according to the new regulation(National technical regulation QCVN04/05/2012/BNNPTNT) design safety level must increased.Therefore, the risk of breaking earth dams is huge when a big flood occurred On the downstream ofthe dams, people have settled down to live and produce stably including 399 households and 1,326.2

ha of land If the dam is broken, the loss of life and property of the people living downstream is huge.Status of reservoirs is presented in details in Annex 2.2.1 of this report

4 Results of environmental and social screening:

5 The subproject is not located in or near natural habitats and there is no rare or endangered speciesfound in the subproject area The neighborhood of the subproject has sensitive objects such as: there is

an ancient tomb in upstream of Tram Sat reservoir; a shrine in the right shoulder of main dam Dat Doi

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reservoir There are some graves located near management operation road of Vo reservoir and DocGao reservoir No sensitive objects have to relocate during the construction of the subproject Duringthe implementation of the subproject, having 12 households of ethnic minority will lose their land,among them 02 households have to resettle, the remaining households will lose their agricultural land,forestry land and aquaculture land Therefore, the subproject will trigger OP/BP 4.10 Indigenouspeoples to provide more socio-economic benefits for ethnic minority groups in the subproject area ingeneral and complement the benefits of the Sub-project in particular The subproject is only upgradingthe dams on the existing reservoirs which have been clarified, via social and environmental screening,that the effects on environment and society in the project area are from minor to moderate Thesubproject is classified as Category B on environmental assessment Safeguard policies triggered forthe subproject include: OP/BP 4.01 on environmental assessment, OP 4.09 on pest management,OP/BP 4.37 on safety of dams, OP/BP 4.12 on involuntary resettlement; OP/BP 4.10 on Indigenouspeoples, and OP/BP 4.11 on Physical Cultural Resources.

The social and environmental impact assessment aims to identify both potential positive and negativeimpacts of the subproject, thereby proposing appropriate mitigation measures to control and managethose impacts, in order to optimize the benefits of the subproject

6 Social and environmental impacts of the subproject: The subproject brings both positive and

negative impacts

(a) Positive impacts:

- The subproject will repair and upgrade head works of reservoirs to ensure safety for peopleand their assets who live in the downstream area, and communes in subproject and residents ofneighboring affected areas;

- After being implemented, the subproject will improve the water storing capacity of reservoirs,improve water recharge for underground water in the nearby area;

- Provision of regular and stable irrigation water for agriculture cultivation area in thedownstream area;

- Improvement of landscape in the reservoir area and provide habitat aquatic life

(b) Negative impacts during the process of preparing and constructing the subproject: Potentialnegative impacts include:

- The implementation of the Phu Tho subproject will affect 100 households, of which 97households are directly affected by land acquisition activities and 3 CPCs Theimplementation of the subproject will also affect 18,000m² of land of 97 households and 3CPCs, including 873 m2 residential land The total agricultural area being affected is: 7,106

m2 The affected productive forest land is 3,730 m2 The affected Aquacultural land is 3,591

m2 The affected public land under the management of 3 CPCs such as special-use land, dikecorridors, and traffic land is: 2,700 m2;

- According to the results of consultations and interviews in the subproject area, the UXO is notobserved in the area However, in the Phu Tho province UXO still observed and treatedaccordingly According to a report on the status of landmine and UXO contamination(Vietnam National Mine Action Center) there are 13/13 districts (cities and towns)contaminated with UXO such as: Viet Tri city, districts: Doan Hung, Thanh Ba, Ha Hoa, CamKhe, Yen Lap, Thanh Son, Phu Ninh, Lam Thao, Tam Nong, Thanh Thuy and Tan Son.Therefore, UXO may be found in the construction area or soil, stone mines In order tominimize risks, the subproject owner will contact the competent authorities to conduct mineclearance to ensure safety of explosive objects before construction

- Site clearance and preparation activities including top-soil and vegetable cover transportationmay create impacts: Dust, exhaust gas, noise, vibration affect construction workers, peopleliving in the subproject area; Wastewater being created by activities of worker and stormwaterrunoff, which erode the bare land, will affect the quality of receiving water body and soilquality in the subproject area; Solid waste being created by activities of workers and wastedvegetable cover will affect the surrounding environment and landscape of the subproject areaunless its are being managed properly

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- Another activity in the project preparation phase is geological exploration drilling: the drillingholes, with depth varied from 10 m to 30 m, if not backfilled properly may create the route tocontaminate groundwater by infiltration of contaminants from surface water;

- The impacts related to construction activities such as noise, vibration, air pollution due to dustand emissions, water pollution, waste, fauna and flora, social risk due to site clearance,transportation andconstruction activities, namely: traffic safety, degradation of communityinfrastructure, accidents, social conflict infectious disease and disruption of business activitieshave been also identified and assessed in the report Moreover, during the constructionprocess, it may be blocked water source to construct the works of the subproject which mayinterrupt water supply and affect agricultural productivity of 13 communes in the subprojectarea The works of the subproject are scattered in the 13 village/13 communes of 7 districtsand the implementation location is mainly on agriculture land which is far from residential,important water body and forestry land; therefore, the negative impacts of the subproject areassessed at low to average level and can be controlled by a proper management plan.However, there are still long term impacts on the subproject area such as land mine anddumping sites which can cause degradation of agricultural land, unused hill land, and vacantland within the temporarily borrowed pits

(c) Negative impacts during the operational stage:

- The risks of broken dam or flood discharge may causing flooding downstream; Accidentrelated to drowning

- Domestic waste from eco-tourism activities in some reservoirs

- The implementation of the subproject does not increase the capacity of the reservoir, does notincrease the irrigating area in the downstream area and does not affect the crop structure in thesubproject area However, the repair of the damaged culverts and prevention of water leakagewill restore designed performance of reservoirs, provide stable irrigation water regulation andadequate irrigation water in the drought season On one hand, the cultivation of agriculturalcrops for areas in the drought season will be restored, but on the other hand, when there isenough irrigation water and water is frequently circulated, it leads to changes in livingenvironment, creating conditions for harmful organisms and plants to grow, This is also thecause of outbreaks of diseases and pests for agriculture Therefore, it may increase the usage

of pesticides and fertilizers in the being benefitcary area Beside the usage of termite-cidesmay affects the surrounding environment unless its being used and managed properly.Therefore, an integrated pest management (IPM) plan for this subproject is necessary

7 Mitigation measures: To manage these potential negative impacts, an Environmental and Social

Management Plan (ESMP) has been prepared as part of this ESIA document with proposedinstitutional arrangements for impacts management, environmental management and monitoring,reporting requirements, capacity building, budgeting for implementation The social assessment report(SA) is also conducted focussed the following objectives: (i) Identify social issues and potentialimpacts of proposed infrastructure investment items, (ii) Provide i social diemsions for conductfeasibility study, project design since basic design phase, (iii) Provide specific recommendations onmanagement of infrastructure investment with high social risks and identify criteria and methodologies

to determine whether the investment is socially acceptable or not, (iv) Provision of data to evaluatingresults of project completion A separated Resettlement Action Plan/Compensation and Resettlementplan has been prepared to deal with the impacts of land acquisition An ethnic minority developmentplan (EMDP) is implemented to: (i) Summarize the potential impacts of the subproject on ethnicminorities and propose mitigation measures; (ii) Propose development activities that need to beimplemented to ensure that ethnic minority people in the subproject area receive socio-economicbenefits that are harmonize with their culture The development activities presented in the EMDPreport are proposed on the basis of consultation with ethnic minorities located in the subproject impactarea The following are the measures to be taken:

Preparation phase:

- Implementing RAP, SA, and EMDP

- Integrating environmental mitigation measures into technical design if possible

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- Consulting with people about the actual time of repairing dam with purpose of mitigatingimpacts of three phases: preparation, construction of subproject and operation of subproject.

- Integrating all safeguards requiremnts into construction bidding documents and constructioncontracts

Construction phase:

- Require contractors to strictly and fully implement mitigation measures for the impactsdetermined in the Environmental and Social Impact Assessment Report, social impactassessment report of the subproject and negative impacts during construction phase have to beminimized based on ECOP and mitigation measures for site-specific impacts

Operation phase:

- The upgraded reservoirs on one hand serve better conditions for irrigation in the benefitcaryarea, but on other hand it also may cause increase usage of fertilisers and pesticides in thesame area Therefore, introduction and promotion of application of integrated pestmanagement in the areas of irrigation services is necessary

- PPMU frequently monitor to ensure that the damaged structures will be repaired and restored

in accordance with the approved document Reservoir management units regularly check damsafety and patrol the reservoir area to avoid drowning accidents; forecast and warning toauthorities and people when there are extreme weather phenomena Regularly collect garbage

at the reservoir area, for reservoirs operating in tourism business, there must be garbage binsand coordinate with a local environmental unit to collect daily

- For the impact of increased use of pesticides, agencies: Plant Protection Department of PhuTho province; Plant Protection Station of districts under the subproject; and the People'sCommittee of 13 communes under the subproject must comply with the contents of the PestManagement Plan (IPM) of this subproject In addition, farmers in the process of cultivationneed to select good varieties, regularly check pests and diseases, use pest control measuresrecommended in the pest management plan (IPM) such as: (i) Cultivation measures: Soilpreparation, field cleaning; rotation, intercropping; proper time; sowing and plantingreasonable density; use fertilizer properly; Appropriate care measures (ii) Use of breeds:Traditional varieties and proposed varieties suitable for local conditions (iii) Biologicalmeasures: taking advantage of using natural enemies available in the field, using bioproducts

…(iv) Chemical measures: use of pesticides safe for natural enemies; follow economicthreshold Follow safety guidelines on pesticide storage, transportation and use to minimizenegative environmental and health impacts…

8 Institutional Arrangements: The Ministry of Agriculture and Rural Development (MARD) is

responsible for implementing and managing the entire project Provinces that perform repairs to dams

in Component 1 and MARD will coordinate activities with the Ministry of Industry and Trade and theMinistry of Natural Resources and Environment in Component 2 Central Management Board(CPMU) under MARD is responsible for coordination and overall monitoring of the project Theimplementation of repairs and preparations for the dam safety plan, including protection andentrustment, is focused on provincial authorities Provincial People's Committee is the chair of theprovincial level The Provincial Project Management Unit (PPMU) is responsible for managing andmonitoring the works with support from CPMU Management Unit of Dam rehabilitation and SafetyImprovement (WB8), Phu Tho province (hereinafter referred to as PMU) responsible forimplementing and monitoring implementation ESIA The PPMU ensures that bidding and contractualdocuments and contracts for valid bidding include environmental provisions for contractor’scompliance The contractor will carry out construction activities and comply with the environmentalcovenants as agreed in the contract In particular, the contractor will prepare an Environmental andSocial Management Plan for the PPMU to review and approve before starting construction PPMU andtheir consultants will closely monitor contractor’s compliance agreed mitigation measures In addition,the contractor's compliance will be closely monitored by Department of Natural Resources andEnvironment of Phu Tho province, local authorities and people

9 Capacity building: During the implementation process, PPMU has received support from CPMU

on the World Bank's environmental safety policy The PPMU's safeguard staff has been trained by

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CPMU in coordination with the World Bank experts to guide the project's environmental safeguardissues and World Bank's safeguard policies related to the project implementation included: OP4.1(Environmental Assessment), IFC's General Guidelines on Environment, Health and Safety (EHS),

OP4.04 (Natural Habitats), OP 4.10 (indigenous peoples) và OP4.12 (involuntary resettlement), etc.

10 During the implementation of the subproject, training on environmental safeguard policies forConstruction Supervision Consultant (CSC) and EHS staff of the contractor are carried out regularly toupdate the relevant information For PPMU, during the implementation of the subproject, thesubproject will receive regular support from CPMU's independent and technical assistance consultants

on the management of dam safety risk issues, monitoring the implementation of the ESMP

11 Public consultation: During the period of March 2019, ESIA preparation consultant conducted

01 time consultation at provincial, district level and 01 time consultation in 13 subproject communes,Participants in community consultation include: Leaders of Commune People's Committee,representatives of the Fatherland Front Committee, socio-political organizations, job socialorganizations and affected households by the subproject (With a total of 255 participants, of which

136 are male and 119 are female) The main contents are a general introduction of the subproject'scapital source, program of the subproject, A brief description of the proposed technical options andenvironmental, social impacts and measures to minimize negative impacts during construction andoperation, consult the representatives of local authorities and the people 's community on impacts andmitigation measures during the preparation and construction process After the consultation process,local opinions are directly listened and recorded by the PPMU and consultants Agencies, localauthorities and communities all agree to invest in the Sub-project; the Subproject Owner andconstruction contractors involved in the construction of the subproject are required to fully implementtheir commitments to mitigation and minimization of adverse environmental and social impacts.Further consultations will be conducted regularly during the construction process to address issuesrelated to social-environmental impact assessment in timely manner

12 Cost estimation for ESMP implementation: ESMP implementation cost estimate includes costs

for ESMP monitoring, mitigation measures implementation and capacity building Mitigationmeasures implementation cost shall be included in the construction cost Cost estimates for ESMP

implementation are: 573,940,556 VND Details are as follows:

Table 2: Cost estimate for ESMP implementation

1 Costs for environmental monitoring 404,764,142

2 Costs for pollution control and mitigation 117,000,000

3 Contingency (10% of 1+2) 52,176,414

13 Grievance Redress Mechanism (GRM): Complaints related to the subproject will be resolved by

negotiation to get an agreement with the affected people Complaints will be negotiated by the parties

at all three stages (People's Committee at commune, district and provincial levels) before submitting tothe court in accordance with the 2011 Complaint Law PPMU will pay all administrative and legalcosts related to the receipt of the complaint because this payment cost is included in the subprojectbudget

14 Information disclosure: The compliance with policy of OP 4.01 and policies of World Bank on

access to information: from the stage of preparing the subproject, relevant information has beendisseminated to local communities through mass media PPMU disseminated information and directlyconsulted community in 3/2019 and sent related information for consultation to local organizations.The draft ESIA in Vietnamese was sent to CPCs to disseminate information and consultation in3/2019 The final version is expected to be disclosure in 07/2019 on the project website and atsubproject sites accessible to locally-affeted peope and local NGOs in Vietnamese language and on theBank external website in English before appraisal of the subproject

15 Conclusion: Subproject: dam rehabilitation and safety improvement (WB8) in Phu Tho province

may have potential negative impacts in the subproject phases, but due to the small scale ofconstruction items, impacts will occur in a short time, small in spartial scale and insignificant, somitigation measures proposed by the sub-project are considered feasible and suitable to the natural,

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socio-economic conditions at localities.

16 The Environmental and Social Management Plan is prepared as an integral part of this ESIA tomanage the subproject impacts and update local people and authorities on the implementation process

of subproject items The monitoring plan will be followed during the implementation of subproject.Construction supervision consultants shall regularly check and prepare monthly reports to submit toPPMU

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CHAPTER I: PROJECT INTRODUCTION 1.1 Overview of the project

17 Vietnam is one of the nations that own largest networks of dams and hydraulic infrastructure in theworld, including 7,000 dams of different types and sizes More than 750 dams are able to be classified

as large dams (over 15m high or between 5 and 15m high with the water reservoir storage in excess of3,000,000 m3) The number of small dams (less than 15m with the water reservoir storage lower than3,000,000 m3) is estimated to be over 6,000, which are mainly earth dams Of the total 4,000,000 ha ofagricultural land, more than 3,000,000 ha are irrigated by 6,648 dams

18 Many small-medium reservoirs were built since 1960s with limitation of technical surveys,designs and construction and limitation in operation and maintenance as well As a consequence,many reservoirs have been degraded, unsafe and failed to meet the international safety standards Inaddition, increasing risks of unstable hydrology due to climate change and massive upstreamdevelopment make reservoirs at risks of subsidence of major structures, leakage of main dams and/orsubsidiary dams/surrounding water-intake works, deformation of upstream/downstream slopes,spillway incidents, etc

19 Awareness of the importance of infrastructure for the country’s sustainable economic growth, theGovernment launched a multi-sector program in 2003, including the “Dam Rehabilitation and SafetyImprovement Project”(DRSIP) financed by the World Bank, which supports dam safety and reservoirsand operational safety to downstream populations and socio-economic infrastructure that are at risk,ensures the downstream integrated development planning and strengthens institutional coordinationand future development and safe operation of reservoirs

20 The Ministry of Agriculture and Rural Development (MARD) is responsible for theimplementation and management of the entire project The Provinces repair and upgrade dams underComponent 1 and MARD will coordinate activities with the Ministry of Industry and Trade (MOIT)and MONRE under Component 2 The CPMU (under MARD) is responsible for coordinating andmonitoring the entire project The repair and preparation of dam safety plans, including protection andcommissioning, are centered on provincial government The Provincial People's Committee (PPC), theDepartment of Agriculture and Rural Development (DARD) are the managers at the provincial level.The PPMU is responsible for managing and supervising the works with the support from the CPMU

21 The selection of rehabilitation dams by the Project was based on unified criteria, probability andseverity of incidents and risks to human and socio-economic infrastructure, paying importance ofeconomic benefits in the poverty and inequality framework The assessment criteria for dam safetyinclude: (i) dam incident probability (structural risk that is based on height and capacity); (ii) impact ofdam incident on downstream people; (iii) impact of dam incident on downstream infrastructure, (iv)context of poverty and impact, (v) areas of ethnic minorities; and (vi) the readiness

22 The Project is implemented in 34 provinces in the North, Central and Highlands There are about

450 selected dams The project components include:

- Component 1: Dam Safety Rehabilitation (US$ 412 million, of which IDA’s funding is US$388.5 million)

- Component 2: Dam Safety Management and Planning (US$ 20 million, of which IDA’sfunding is US$ 17 million);

- Component 3: Project Management Support (US$ 11 million, of which IDA’s funding is US$9.5 million);

23 In the second year, the Project will support the repair and solidification of related infrastructureand dams About 90% of the proposed dams are earth dams which are less than 15m high and theirdesign capacity are less than 3 million m3 The Project does not invest in completely changing existingstructure or new construction or expansion of main structure but focuses on repairing and re-shapingstructure of main dams, secondary dams, strengthening upstream slope by concrete and stones,reinforcing or expanding spillways to increase drainage capacity, repair or rehabilitation of existingintake culverts, replacement of hydraulic system at sluice gates (intake culverts) and spillway gate,drilling for waterproofing of the main dam bodies, upgrading service roads

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24 The implementation of the Project is expected for 6 years, 08/7/2016 - 30/6/2022 Regardingenvironmental safeguard, the Environmental and Social Management Framework (ESMF) of theproject was approved and disclosed since 2015 The Environmental and Social Impact Assessment(ESIA) for the next years of the subprojects will follow the project progress agreed between theCPMU, the PPMU and the World Bank.

25 In Phu Tho province, the Dam Rehabilitation and Safety Improvement Subproject is to ensure thesafety of the reservoirs through the repair and rehabilitation of 13 dams and strengtheningmanagement capacity and safe operation of dams to protect inhabitants and socio-economicinfrastructure in 13 communes in 7 districts: Doan Hung, Thanh Son, Thanh Ba, Yen Lap, Cam Khe,

Ha Hoa, Thanh Thuy

1.2 Approaches and methodologies

26 The Environmental and Social Impact Assessment (ESIA) is implemented in accordance with theWorld Bank’s regulations and the Law on Environmental Protection and other laws and regulations ofthe Government of Vietnam The purpose of the ESIA is to identify the importance of environmentaland social issues in the decision-making process by assessing environmental and social consequences

of the proposed research before undertaking the project activities Early identification andcharacterization of important environmental and social impacts will help communities andgovernments assess potential environmental and social impacts of the proposed subproject and applymitigation measures to minimize the risk of such effects

1.2.1 Methodology for social impact assessment

27 The objectives of the social assessment (SA), in parallel with the environmental assessment of theSubproject, include: First, it examines potential impacts of the subproject–positive and negative–onthe basis of planned subproject activities Second, it finds from the design of measures addressingpotential adverse impact and proposing community development activities that are relevant to theproject development objectives For identified adverse impacts, consultation with local people,governmental agencies, project stakeholders, etc., were carried out to ensure that affected people will

be appropriately compensated and supported in a manner that their socio-economic activities will bepromptly and fully restored to the pre-project level, at least, and that their livelihoods will not be worseoff, in the long run, as a result of the subprojects

28 A part of the social assessment is ethnic minority (EM) peoples who are living in the subprojectarea and are confirmed by the EM screening (WB’s OP 4.10) The consultations with them werecarried out in a free, prior, and informed manner to confirm supports for affected EM peoples whenthere is the subproject implementation The EM screening was conducted based on WB’s OP 4.10 andimplemented within the social assessment scope and area corresponding to the scope of theenvironmental assessment (according to OP 4.01)

29 A gender analysis in the subproject area was also done as part of the SA to understand genderfeatures in the subproject area to enable gender mainstreaming to gender equality improvement and toenhance further development effectiveness of the subprojects and the Project as a whole Depending

on the magnitude of the identified potential project impacts and the project development objectives, agender action plan and a gender monitoring plan were prepared

30 To ensure that any potential impacts can be identified during the project preparation, the SA wasconducted through series of consultations with the stakeholders A particular focus was the householdswhich are potentially affected (both positively and adversely) by the Subproject The assessmenttechniques for this SA include i) review of secondary data, ii) field observations; iii) focus groupsdiscussions/community meetings, iv) key informant interview, and v) households survey

1.2.2 Methodologies for environmental impact assessment

31 During the ESIA survey and reporting, the Consultant Agency used a combination of the followingmethods

(1) Rapid assessment method

32 The Rapid Assessment Method was issued by the World Health Organization in 1993 The basis ofthis method is based on the nature of material, technology, rules of processes in nature and experience

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to quantify pollution load.

33 In Vietnam, it has been introduced and applied in many CESMP studies, which performs relativelyaccurately the calculation of pollutant discharge under limited conditions of instrumentation andanalysis In this report, the pollutant discharge coefficients are taken from the World Bank’sEnvironmental Assessment Sourcebook (Environmental Assessment Sourcebook, World Bank,Washington D.C 8/1991)

(2) The method of building impact matrix

34 Establishing correlation between impact of each project activity on each issue and environmentalcomponent as shown on the impact matrix, which is basic for the focus on detailed contents of impactstudy

(3) Comparative method

35 The comparison method is to evaluate the environmental quality, effluent discharge quality,pollutant discharge load on the basis of comparison with the relevant environmental standards andregulations of MONRE and MOH as well as related research and experiment topics

(4) Description of environmental system

36 Identifying subproject components that affect the environment and identifying in full effluents,related environmental issues for detailed assessment

(5) Enumerating method

37 It is used extensively (since the National Environmental Protection Agency (NEPA) has beenestablished in some countries) and yields positive results thank to its advantages as mentioned abovesuch as clear approach and systematic supply during system analysis and evaluation There are twomain construction items: A descriptive list of the environmental components to be studied along withmeasurement, forecasting and evaluation, a simple list of environmental components which are likelyaffected to be studied

(6) System analysis method

38 This method is quite popular in the environment assessment The advantage of this approach is thecomprehensive assessment of impacts, which is very useful in identifying impacts and sources ofwaste It is based on the assessment of waste sources, impacted objects, environmental components,etc., as the elements in a system have close relationship with each other, thereby, we can identify,analyze, and evaluate impacts

(7) Community consultation method

39 This method is used during interviews with local leaders and local people to gather necessaryinformation for the Subproject's ESIA preparation, introduction of benefits and possible negativeimpacts of the Subproject on the environment and the life Based on that, we can aggregate feedbackand aspirations of local people

40 On the other hand, we can directly interview local officials and local people on socio-economicdevelopment, farming practices and environmental sanitation

(8) Method of collection and analysis of information and data

41 This method aims at identifying and evaluating natural and socio-economic conditions in thesubproject area through data and information collected from different sources like statistical yearbook,socio-economic report, current status of environment and related research works

(9) Field survey method

42 Field survey is required when carrying out the assessment of socialand environmental impacts todetermine the current status of the subproject area, related objects and to select sampling locations,survey of status of water supply, drainage, electricity supply etc

43 The consulting agency carried out topographical and geological surveys and collectedhydrometeorological data for design in accordance with the current standards of Vietnam Thesesurvey results are used to assess the natural conditions in the subproject area

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(10) Expert method

44 Based on the knowledge and experience of environmental science of environmental impactassessment experts of the Consultancy Agency and other scientific research agencies

(11)Method of sampling and analysis in laboratory

45 Sampling and analysis of environmental components (soil, water, air) is indispensable inidentifying and assessing the status of baseline environment quality in the subproject area

46 After field survey, the sampling and analysis program will be developed with the main contents assampling locations, measurement and analysis parameters, manpower, equipment and tools in need,implementation time, sample preservation plan, analysis plan etc

47 For Phu Tho subproject, the Consultant coordinated with the Environmental Monitoring Agency tomonitor, take and analyze samples of air, water and soil in 13 reservoirs to assess the current quality ofenvironment components The sampling, analysis and preservation are in accordance with theconcerned current standards of Vietnam

1.3 Implementation arrangement of ESIA report

48 Management of the subproject

- SubProject Owner: People's Committee of Phu Tho province

- SubProject Owner representative: Phu Tho project management unit of constructioninvestment works for agriculture and rural development;

- Represent: Mr: Nguyen Duc Luong - Position: Director;

- Address: No 215, Minh Lang Street, Tien Cat Ward, Viet Tri City, Phu Tho province

- Phone: (0210)3812890 - Fax: (0210)3846172

49 Consultant

- Thang Long infrastructure technology construction consultant joint stock company

- Represent: Mr Tran Trung Kien - Position: Director

- Address: No 72/1/4, nest 4, Giap Nhat, Nhan Chinh ward, Thanh Xuan, Ha Noi

- Phone: 024.3575 6806 - Fax: 024.3575.6806

50 Coordinating unit to implement environmental monitoring:

- Thai Duong environmental treatment and monitoring joint stock company

- Address: No 24, Lane 18, Phan Van Tri Street, Quoc Tu Giam Ward, Dong Da District, HanoiCity

- Phone: 024 3573 7766 Fax: 024 3577 3403

- Certificate of Eligibility for Environmental Monitoring Service No.: VIMCERTS 163 issued

in accordance with Decision No 194 / QD-BTNMT dated 13/5/2016 of the Minister ofNatural Resources and Environment on the certificate of eligibility event of environmentalmonitoring service

Table 3: List of persons participating in implementation

1 Nguyen Hoai Nam

Team leader / environmental specialist - Participate inField Survey; Community consultation; Summary ofgeneral topics; write ESIA report

2 Vu The Hai

Irrigation expert - Participate in Field Survey; Communityconsultation; Synthesis of irrigation topics; write ESIAreport

3 Ha Thi Quyen

Ecology Specialist - Participate in Field Survey;Community consultation; Summary of ecological topics;write an ESIA report

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No Full name Tasks performed

4 Nguyen Duc Anh

Support staff - Support field survey experts; communityconsultation, data collection and synthesis Photographingthe scene

5 Nguyen Van Chien

Vice Team / Social Specialist - Participate in Field Survey;Community consultation; Synthesis of social topics; write

an ESIA report

6 Nguyen Quang Ninh

Specialists on land clearance and resettlement Participating in field surveys; Community consultation;Synthesis of land clearance and resettlement topics; write

-an ESIA report

7 Duong Thi Phuong Thuy

Support staff - Support field survey experts; communityconsultation, data collection and synthesis Photographingthe scene

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CHAPTER II: DESCRIPTION OF SUBPROJECT 1.4 Overview of the subproject

51 Subproject: dam rehabilitation and safety improvement (wb8) in Phu Tho province under theproject of dam rehabilitation and safety improvement, WB8 is financed by the World Bank through theCredit Agreement No 5749-VN dated on 08th April, 2016 with the subproject implementationduration from 2017 to 2022 Basing on Decision No 4638 / BNN-HTQT dated 09th November 2015

by Ministry of Agriculture and Rural Development, the Dam rehabilitation and Safety improvementsubproject in Phu Tho province is implemented in 13 communes under 7 districts: Doan Hung, ThanhSon, Thanh Ba, Yen Lap, Cam Khe, Ha Hoa, Thanh Thuy

2.1.1 Name of the subproject

- Subproject: dam rehabilitation and safety improvement (wb8) in Phu Tho province under theproject of dam rehabilitation and safety improvement, WB8

2.1.2 Owner of the subproject

- SubProject Owner: People's Committee of Phu Tho province

- SubProject Owner representative: Phu Tho project management unit of constructioninvestment works for agriculture and rural development;

- Represent: Mr: Nguyen Duc Luong - Position: Director;

- Address: No 215, Minh Lang Street, Tien Cat Ward, Viet Tri City, Phu Tho province

- Phone: (0210)3812890 - Fax: (0210)3846172

2.1.3 Objective of the subproject

a. Objective of the subproject:

52 Support to implementation of program to ensure safety of water reservoirs through rehabilitationand upgrading of prioritized dams, strengthening management capacity and safe operation of dam toprotect population and economic - social infrastructure in downstream area

b. Specific objectives:

- To secure the safety of reservoirs and key works

- To improve the efficiency of irrigation works in service of intensive cultivation, increaseproductivity and quality of products, develop specialized areas of high yield and higheconomic value, maximize potential of agricultural land in the region

- To reduce water loss, to ensure the water demand for people's life, the development of localindustries, and socio-economic development in the subproject area in particular and Phu Thoprovince in general

- To create natural landscapes, improve the ecological environment, promote tourismdevelopment in the region

2.1.4 Location of subproject implementation

53 Subproject: dam rehabilitation and safety improvement (wb8) Phu Tho province consist of 13works at the following locations:

Table 4: Geographic location of reservoir under the subproject

No Name of

Google Earth coordinates North latitude East longitude

1 Da Den Yen Kien commune, Doan Hung district 21°34'26.85 105° 9'32.59"

2 Nha Giac Van Du commune, Doan Hung district 21°40'14.02" 105°10'40.91"

3 Nui Dau Ngoc Quan commune, Doan Hung district 21°36'36.89" 105° 8'19.07"

4 Dam Gai Luong Nha commune, Thanh Son district 20°58'59.26" 105°18'57.14"

5 Tram Sat Do Son commune, Thanh Ba district 21°23'25.19" 105°11'22.01"

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No Name of

Google Earth coordinates North latitude East longitude

6 Vo Luong Son commune, Yen Lap district 21°26'8.22" 104°58'9.51"

7 Dat Doi Phuong Vi commune, Cam Khe district 21°25'43.73" 105° 0'55.53"

8 Ba Gac Ninh Dan commune, Thanh Ba district 21°28'34.43" 105°10'16.96"

9 Cay Quyt Hau Bong commune, Ha Hoa district 21°37'58.76" 104°55'36.96"

10 Doc Hep Dao Xa commune, Thanh Thuy district 21°13'59.70" 105°15'56.67"

11 Su Tan Phuong commune, Thanh Thuy district 21°11'5.06" 105°17'14.54"

12 Doc Gao Dieu Luong commune, Cam Khe district 21°19'10.99" 105°10'15.04"

13 Vinh Lai Hung Quan commune, Doan Hung district 21°40'54.41" 105° 8'40.28"

Figure 1: Locations of subproject reservoirs

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1.5 Status of works and construction solutions

Table 5: : Summary of current information of reservoirs and construction works of the Subproject

1 Da

Den

reservoir

- Da Den reservoir has a capacity of

0.32*106 m3; The dam height is 8.9m

1 Main dam

Dam crest:

- The main dam has a length of 160m,

the average width of the dam crest isabout 6.0m in which the sectionfrom K0 + 50m to K0 + 100m isspread stone 0x4 width 3.0 ÷ 3,50mhas peeling, the remaining sectionsare soil The dam crest elevation isabout + 46.25 ÷ 46.85m

- There is no wave wall on the dam

crest The dam crest has no lightingsystem

- The dam crest has no wheel guard

edges

- The results of water infiltration of

dam body and dam foundation showthat the permeability coefficientexceeds the permissible level:

K=1,8E-4 cm/s ÷2,7xE-4 cm/s(permeat in dam body and damfoundation)

Dam slope:

- Coefficient of upstream slope

current status 1:3,2 & 1:5,7, withoutbanquette The dam slope has notbeen reinforced, the plants growmuch

- Coefficient of downstream slope is

1:2.5 and 1:3.0, The downstream

- Upstream slope: Upstream slope coefficient m

= 3.00, reinforced from the elevation + 42.30m

to the top of the dam by reinforced concretesheet M200 (200x200x10cm), under a solidtarpaulin lining, 5cm macadam, filter cloth

- Downstream slope: slope coefficient m = 2.75,Plant grass in rectangular M200 concreteframe, 30cm deep groove, 30cm wide bottomdistance between grooves is 5.0m ditchcollecting water at the position of the foot ofthe downstream dam slope is formedtrapezoidal BxH = 0.5x0.4, slope 1: 1.0structure anhydrous stone slices, with athickness of 30cm, Below is a reverse filterlayer consisting macadam thickness of 15cmand filtered sand thickness of 15cm Elevation

of reinforced downstream of the dam: +41.00m;

- Waterproofing of dam body and foundation:

from K0 + 030 to K0 + 090 (L = 60m) Option

Dam crest

Upstream slope

Downstream slope

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Location Current status Proposed construction activities Pictures

slope of the dam has not beenreinforced, the trees are overgrownwith a phenomenon of termites,water seeps into the position on theslope near the foot of the dam

2 Spillway:

- The results of the field survey show

that there is no overflow at thespillway location, only 05 PVCpipes D = 30cm temporarily underthe dam at the at the left shoulder, atposition K0 + 151m, elevation ofplacing pipes for flood discharge is+ 43.11m Downstream is thechannel, made of soil, Overgrownplants, on the downstream channeloverflowing from the dam heartabout 50m has 1 regulating intakemade by concrete is damaged

3 Intake:

- Intake at the right shoulder of the

dam (K0 + 015m), intake diameter

D = 60cm, intake bottom elevation +39.50m

- The survey results show that: there

is no water regulation device atpresent, water flows freely throughthe intake Doors to the intake areinserted with soil sacks The outletgate for water intake is made ofconcrete that has been stronglyeroded, The serial part behind theintake, made of soil is alreadydegraded, and eroded

- Form: Wide peak spillway, free-flowing

- Structure: Reinforced concrete M250,

- Spillway width: 6.50m

- Threshold spillway have elevation: +43.30m

3 Intake: Destroy the old intake, new intake construction with scale:

- Form: circular intake, Reinforced concreteM300, steel pipe wrap

5 House under management:

- New construction of house under management,level 4, using area of 76m2,

Status of the intake

Spillway threshold

Management road

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leading to the dam crest: Route 1 isthe main road by soil, 2 sub-roads 2and 3 with concrete going fromdownstream to the top of the dam

The main road with a width of 4.0 ÷6.0m with stone 0x4 cover haspeeled and swamped difficult totravel in the rainy season

5 House under management:

- Currently the reservoir does not

have house under management, it isnecessary to arrange house undermanagement for this reservoir

2 Nha

Giac

reservoir

- Nha Giac reservoir has a capacity of

0.6*106 m3; The dam height is 8.5 m

1 Main dam

Dam crest:

dam crest width 3.30÷3.90m, thedam face has not been reinforced

The surface of the dam is not flatwith current elevation in the range+32.76÷33.21m There is no wavewall, no wheel guard, no lightingsystem;

- Thick vegetation on the top of the

dam;

dam body and dam foundation showthat the permeability coefficientexceeds the permissible level: K =2E-3 cm / s ÷ 5E-4 cm / s(permeability high both body andbackground)

Dam slope:

- Status coefficient of upstream slope

1 Main dam and Auxiliary dam

- Main dam crest and auxiliary dam are leveled,creating dam elevation + 33.00m;

Embankment to create the downstream slope

to widen the dam crest to 5.0m Reinforce thedam crest, length 114.0m long with cementconcrete M200, with a thickness of 20cm,under is regenerative canvas, the dam surfacecreates a slope of 3% to 2 sides Upstream anddownstream, layout of wheel guard, ofconcrete M200, monad 4.8m, 2-layer asphaltoil paper at the junction between the monad

Reinforcement of downstream roof top withM100 mortar with length 1m, thickness of20cm

- Upstream slope dam of main dam andauxiliary dam: coefficient upstream slope m =3.00, reinforced from the elevation + 29.5m tothe top of the dam by reinforced concrete sheetM200 (200x200x10cm), under a solidtarpaulin lining, 5cm filter particle, filter cloth

- Downstream slope of main dam: Coefficient ofslope m = 2.75, Plant grass in rectangular

Dam crest

Downstream slope

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is in: 1: 2.0 & 1: 5.0, no muscle Thedam slope has not been reinforced,the plants grow much Downstream

of the dam foot has a water leakphenomenon

- Status coefficient of downstream

slope is 1: 3.0, The downstreamslope of the dam has not beenreinforced, the overgrown grass,downstream of the dam's feet havewater leakage

2 Auxiliary dam

- Auxiliary dam No.1: has a length of

50m, elevation of dam crest + 33.07

÷ 33.61m, surface width of dam is4.0m

- Auxiliary dam No.2 with a length of

35m, elevation of dam crest+32.12÷32.97m, surface width ofdam is 4.0m

55m, elevation of dam crest+32.52÷33.06m, surface width ofdam is 4.0m

105m, elevation of the dam crest+31.86÷32.75m, surface width ofdam is 4.0m

- Coefficient of upstream slope of

existing dams is about 1: 3.0,

- Coefficient of downstream slope of

sub-dams status is about 1: 2.75,

- Downstream slope of auxiliary dams

have not been reinforced

- The grass grows on the top and the

slope of the dam

M200 concrete frame, 30cm deep groove,30cm wide bottom, distance between grooves

is 5.0m; The water collecting channel of thedownstream slope of the trapezoidal dam BxH

= 0,5x0,4, Slope 1:1.0 of 30cm thick stoneslices below is a reverse filter layer consisting

of 15 cm thick macadam and 15cm thick sandfilter Elevation of reinforced dam downstreamslope of dam: + 26.00m

- Downstream slope of Auxiliary dam:

coefficients of auxiliary dams 1,2,4 m = 2.25,coefficients of auxiliary dams 3 m= 2.75, Plantgrass in rectangular M200 concrete frame,30cm deep groove, 30cm wide bottom, Thegroove is arranged diagonally 45 degrees,density about 10m a groove The watercollecting channel of the downstream slope ofthe trapezoidal dam BxH = 0,5x0,4, slope1:1,0 in 30cm thick stone slices

- Waterproofing body and dam foundation: fromK0 + 015 to K0 + 110 (L = 95m) by a 2-buttondrill

2 Spillway: Break old spillways, build new spillways at existing locations with scale:

- The form of spillway is the spillway with largecrest, free-flowing

- Structure: reinforced concrete M250,

- Spillway threshold elevation: + 31.00m

3 Intake: Embellishment the downstream valve house site, replace the valve door system, create yard of valve house, scale according to existing:

- Intake form: circular intake, Reinforcedconcrete M300, steel pipe wrap

- Intake diameter: D40cm

Upstream slope

Downstream of intake

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3 Spillway:

- Spillway by soil and not located at

the main dams or auxiliary dams butlocated at the inter-commune road,Spillway threshold is currentlyconcrete road, road surface elevation

at spillway threshold of about +33.00m, so the spillway is unable toremove flood

4 Intake:

- Intake is located at the right

shoulder of the dam (K0 + 012),intake diameter D = 40cm, intakebottom elevation + 26.53m

- The new intake has been repaired

for the last 5 years, According to theassessment of the current situation

as well as the management unit, theintake is still good, regulatingoperation guaranteed, however, thesystem of doors, van houses hasdegraded phenomena due to thesurrounding trees tree-covered,however system the door intake,valve house there is degradationphenomenon due to the treesgrowing, covered If there is noreinforcement solution, the overallintake will be degradation veryquickly

5 Management road:

- The management road connected to

the main dam is soil road, width ofroad surface is about 3m Seasonrain swampy, difficult to travel

- Length: 368m

- Road width: 4,00m

- Width of road surface: 3.0m

- Structure of the road: Cement concrete M250,thickness of 20cm, under the lining ofmacadam grade 1, thickness of 15cm

Management road

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3 Nui

Dau

reservoir

- Nui Dau reservoir has a capacity of

0.39*106 m3; The dam height is10.3 m

1 Main dam

Dam crest:

dam crest width is about 3.00m, Thedam face has not been reinforced

The dam surface is not flat with thepresent elevation of about + 49.15 -49.48m There is no wave wall, nowheel guard, no lighting system;

dam body and dam foundation showthat the permeability coefficientexceeds the permissible level: K =2E-3 cm / s ÷ 5E-4 cm / s (permeat indam body)

Dam slope:

is in: 1: 3.8, no muscle The damslope has not been reinforced, theplants grow much Downstream ofthe dam foot has a water leakphenomenon

- slope is 1: 3.0, The downstream

slope of the dam has not beenreinforced, the overgrown grass,downstream of the dam's feet havewater leakage

2 Spillway:

- Currently, the reservoir does not

have spillway and is unable toregulate so the reservoir does notproactive store water

3 Intake:

1 Main dam:

- Digging pit dam foundation simultaneouslywith pit of intake foundation, spillway New ofdam body with the crest width B = 5.0m, damcrest elevation +50.0 m Reinforcement of60m long dam crest with cement concreteM200, thickness of 20cm, Under regenerativecanvas, the dam surface creates a slope of 3%

on both sides In the upstream side, there is areinforced concrete wave wall of M200, 50cmhigh, The downstream, layout wheel guardedges with concrete M200, monad, 4.8m, 2layer asphalt oil paper at the junction betweenthe monad Reinforcement of downstream rooftop with M100 mortar stone of length 1m,thickness of 20cm

= 3.25, reinforced from the elevation +46.50m

of reinforced downstream of the dam: +42.00m

2 Spillway: new spillway construction with scale:

Dam crest

Upstream slope

Downstream slope

Trang 30

- Intake at the left shoulder of the dam

(K0 + 050m according to the surveyroute), intake diameter D = 40cm,intake bottom elevation + 40,76m

- The intake is completely broken, no

longer able to regulate Currentlyfree-flowing water through theintake, discharging to the back of thedam causes serious erosion

- At present, there is a project on

construction of a horizontal roadconnecting the dam with concreteroad B = 6m, so there is no need toinvest in construction ofmanagement road

- Form: The intake combined with flooddischarge regulates the reservoir

Trang 31

4 Dam

Gai

reservoir

- Dam Gai reservoir has a capacity of

3.0*106 m3; The dam height is 7.5m

1 Main dam

Dam crest:

dam crest width, the dam face hasnot been reinforced The surface ofthe dam is not flat with currentelevation in the range+23.34÷23.81m There is no wavewall, no wheel guard, no lightingsystem

dam body and dam foundation showthat the permeability coefficientexceeds the permissible level:

K=0,11E-3 cm/s ÷2,82E-4 cm/s(permeability high both body andbackground)

Dam slope:

is in: 1: 2.30, without banquette Thedam slope has not been reinforced,the plants grow much

is in: 1: 2.20, without banquette Thedam slope has not been reinforced,the plants grow much

- Downstream of dam base has water

leakage phenomena

2 Spillway:

- The spillway is located on the right

shoulder of the dam The width ofthe spillway is 12.0m, Thresholdelevation +22,50m Spillway has

1 Main dam:

- Embankment of downstream slope to createdam crest elevation + 24.00m and extend thedam crest to 5.0m Reinforcement of the damcrest of 390.0m long with cement concreteM200, thickness of 20cm, Under regenerativecanvas, the dam surface creates a slope of 3%

on both sides The downstream, layout wheelguard edges with concrete M200, monad,4.8m, 2 layer asphalt oil paper at the junctionbetween the monad Reinforcement ofdownstream roof top with M100 mortar stone

of length 1m, thickness of 20cm

to the top of the dam by reinforced concretesheet M200 (200x200x10cm), under a solidtarpaulin lining

- Downstream slope: slope coefficient m = 2.00,Plant grass in rectangular M200 concreteframe, 30cm deep groove, 30cm wide bottomdistance, 45-degree oblique layout, density ofabout 10m a trench ditch collecting water atthe position of the foot of the downstream damslope is formed trapezoidal BxH = 0.5x0.4,slope 1: 1.0 structure anhydrous stone slices,with a thickness of 30cm, Below is a reversefilter layer consisting macadam thickness of15cm and filtered sand thickness of 15cm

Elevation of reinforced downstream of the dam+21.50m

K0+10 ÷ K0+170 (L=160m) and K0+220 ÷K0+370 (L=150m) Option of drill 2 buttons

2 Spillway: Destroy the old spillway, new spillway construction at the existing location

Dam crest

Upstream slope

Downstream slope

Trang 32

deteriorated, there is a phenomenon

of water leakage that cannot keepwater The spillway scale does notensure drainage in the flood season:

the flood season in 08/2018 waternear the dam crest, after the floodseason in 8/2018 downstreamspillway is strongly eroded

3 Intake:

- The intake is located at the dam

body at K0 + 155, Intake diameterD=40cm, intake bottom elevation +20.34m

- Intake is completely damaged, no

longer capable of operating forirrigation

- At present, there is a concrete road

connecting to the dam's head sothere is no need to build a road tomanage and connect to the reservoir

with scale:

- Form: horseshoe, free-flowing

- Tram Sat reservoir has a capacity of

2.2*106 m3; The dam height is 7 m

1 Main dam

Dam crest:

the average width of the dam crest isabout 5,50m, The surface of the dam

is not flat with current elevation inthe range +23,05÷23,65m There is

no wave wall, no wheel guard, nolighting system The dam surface iscurrently combined to make inter-village roads;

Dam crest

Trang 33

- Results of experimental water

pouring: coefficient of permeabilityexceeding permissiblelevelK=2,97E-3cm/s ÷3,86xE-4cm/s(Thấm thân và nền đập);

Dam slope:

- Upstream slope: The upstream roof

has been reinforced with pavedconcrete to the normal level of waterlevel is relatively good, no signs ofslipping, coefficient slope of 1: 2.50,

- Downstream slope: the downstream

slope of the dam has not beenreinforced, the average coefficientslope of 1: 2.50, the downstream ofthe dam is the pond area, the foot ofthe dam is seeping, serious slippagedue to the saturated road rising

2 Spillway:

shoulder of the dam, at K0+437,Spillway of width 6.0m, Thresholdelevation +20,80m

- Spillway thresholds, canals and

stone walls are severely degraded,water flows under the bottom of thespillway, stone mortar circuit isbroken

3 Intake:

- Intake is located at the left shoulder

of the dam at K0 + 079, Intakediameter D=80cm, Intake bottomelevation + 19.51m

- The door to the intake is broken,

downstream is leaking, operation isdifficult to regulate, the soil fills the

m = 2.50, Upstream slope has been reinforced,good so keep the status quo

of reinforced downstream of the dam+20.50m, combine pile of stone to drain waterwith stone; 1.5m wide peak, elevation of stonepile top + 19.00m, slope coefficient m = 2.00,

from K0+020 to K0+420 (L=400m) Option ofdrill 2 buttons

2 Spillway: New spillway construction with scale:

Trang 34

door to the door

- The management road connection to

the reservoir is inter-village roadwith average width of 4.0m, dirtroad, muddy rainy season, anddifficult travel

road standard of rural road 2014

-63-TCVN_10380 Length: 514m

- Road width: 5,00m

- Width of road surface: 3,50m

Management road

6 Vo

reservoir

- Vo reservoir has a capacity of

1.68*106 m3; The dam height is 10m

1 Main dam

Dam crest:

dam crest width 4,00m, the dam facehas not been reinforced The surface

of the dam is not flat with currentelevation in the range+54.90÷55.70m There is no wavewall, no wheel guard, no lightingsystem;

1 Main dam:

- Leveling creates elevation of the dam crest+55.50m; Embankment to create thedownstream slope to widen the dam crest to5.00m Reinforce the dam crest, length 100.0mlong with cement concrete M200, with athickness of 20cm, under is regenerativecanvas, the dam surface creates a slope of 3%

to 2 sides Upstream and downstream, layout

of wheel guard, of concrete M200, monad4.8m, 2-layer asphalt oil paper at the junctionbetween the monad Reinforcement ofdownstream roof top with M100 mortar with

Dam crest

Trang 35

pouring: coefficient of permeabilityexceeding permissible levelK=3.53E-3cm/s ÷8.03xE-4cm/s(permeability high both body andbackground)

Dam slope:

- Upstream slope: Upstream slope has

not been reinforced, slopecoefficient 1:1,50, Some positionshave been landslide

- Downstream slope: the downstream

slope has not been reinforced, theaverage coefficient of 1: 2.00, somepositions are landslide

2 Spillway:

- The spillway is located at the left

shoulder of the dam at K0+118,Spillway width 15,0m, Thresholdelevation +53,20m

- The threshold of overflow is still

relatively good, the part of theoverflow wall is eroded anddegraded

3 Intake:

- Intake is located at the left shoulder

of the dam at K0+082, Intakediameter D=40cm, intake bottomelevation +52.01m

- Intake is invested by Luong Son

Commune People's Committee in

2008, currently the sluice is stilloperating, however, the lock valve iswater leak, The downstream valvehouse has deteriorated, damageddoor

length 1m, thickness of 20cm

- Downstream slope: slope coefficient m = 2.75,Plant grass in rectangular M200 concreteframe, 30cm deep groove, 30cm wide bottomdistance between grooves is 5.0m ditchcollecting water at the position of the foot ofthe downstream dam slope is formedtrapezoidal BxH = 0.5x0.4, slope 1:1.0structure anhydrous stone slices, with athickness of 30cm, Below is a reverse filterlayer consisting macadam thickness of 15cmand filtered sand thickness of 15cm Elevation

of reinforced downstream of the dam +48.00m

From K0+010 to K0+130 (L=120m) Option ofdrill 2 buttons

2 Spillway: Destroy the old spillway, new spillway construction at the existing location with scale:

- Form: horseshoe, free-flowing

- Spillway width: 25,00m

- Threshold spillway have elevation: +53,75m

Trang 36

- The management road to the lake is

a narrow, with a width of 3.0 ÷4.0m, swampy and difficult to walk

- New design management road to the grade Croad standard of rural road -63-TCVN_10380-2014

- Length: 312m

- Road width: 4,00m

- Width of road surface: 3,00m

- Dat Doi reservoir has a capacity of

1 Main dam

Dam crest:

dam crest width 3.50÷4.00m, Thesurface of the dam is not flat withcurrent elevation in the range+64.29÷64.63m There is no wavewall, no wheel guard, no lightingsystem Trees grow on the damcrest;

1 Main dam:

- Leveling creates elevation of the dam crest+64.50m; Embankment to create thedownstream slope to widen the dam crest tolên 5.0m Reinforce the dam crest, length188.0m long with cement concrete M200, with

a thickness of 20cm, under is regenerativecanvas, the dam surface creates a slope of 3%

of wheel guard, of concrete M200, monad4.8m, 2-layer asphalt oil paper at the junctionbetween the monad Reinforcement ofdownstream roof top with M100 mortar with Dam crest

Trang 37

pouring: permeability coefficientexceeds the permitted level:

K=9,41E-5 cm/s ÷2,11E-4cm/s

Dam slope:

is:1:3,0, no muscle The dam slopehas not been reinforced, the plantsgrow much

slope is 1:2,2&1:2,3, Thedownstream slope has muscle, width

of 1.5m at the elevation of +56.20m The dam slope has not beenreinforced, the plants grow much

- Downstream of the main dam foot

has water leakage

2 Auxiliary dam

- The Auxiliary dam has a length of

140m, elevation of the dam crest+64,55÷64,61m, dam surface width3,5m;

is: auxiliary dam slope coefficient1:1,5,

- Coefficient of downstream slope of

current auxiliary dam 1:1,5,

- The slope of the lower section of the

Auxiliary dam has not beenreinforced;

slope of the dam

3 Spillway:

shoulder of the Auxiliary dam,Spillway width 10,0m, Threshold

length 1m, thickness of 20cm

to the top of the dam by reinforced concretesheet M200 (200x200x10cm), under a solidtarpaulin lining, 5cm macadam, filter cloth,5cm filtered macadam, filter cloth

- Downstream slope: slope coefficient m = 2.00and m = 2.25 between 2 downstream slopeshave muscle, width of 2.00m at the elevation

of + 56.00m, Plant grass in rectangular M200concrete frame, 30cm deep groove, 30cm widebottom distance between grooves is 5.0m

ditch collecting water at the position of thefoot of the downstream dam slopeis formedtrapezoidal BxH = 0.5x0.4, slope 1: 1.0structure anhydrous stone slices, with athickness of 30cm, Below is a reverse filterlayer consisting macadam thickness of 15cmand filtered sand thickness of 15cm Elevation

of reinforced downstream of the dam+47.50m

2 Auxiliary dam

- Leveling creates elevation of the dam crest+64.50m; Embankment to create thedownstream slope to widen the dam crest tolên 5.0m Reinforce the dam crest, length122.0m long with cement concrete M200, with

of wheel guard, of concrete M200, monad4.8m, 2-layer asphalt oil paper at the junctionbetween the monad Reinforcement ofdownstream roof top with M100 mortar withlength 1m, thickness of 20cm

Upstream slope

Downstream slope

Auxiliary dam

Trang 38

spillway have elevation +62.50m

- The threshold spillway is reinforced

concrete is quite good, other partsare made of soil The downstreamafter the flood discharge spillwaythere are already connecting roads tothe auxiliary dam There are noenergy consumption parts forspillway

4 Intake:

- The intake is located at the right

shoulder of the main dam at:

K0+034, Intake diameter D=40cm,intake bottom elevation +52,25m

- Downstream water intake is water

leak, The flow from the intake leakwater causes landslide downstream

of the dam;

- Valve lock downstream leaking,

tarnish, not able to regulate,downstream valve house degraded

- The management road connection to

the lake is inter-village road with awidth of 3 ÷ 5m, dirt road, muddyrainy season, narrow road travel isdifficult

to the top of the dam by reinforced concretesheet M200 (200x200x10cm), under a solidtarpaulin lining, 5cm macadam, filter cloth,5cm filtered macadam, filter cloth

- Downstream slope: slope coefficient m = 2.00,Plant grass in rectangular M200 concreteframe, 30cm deep groove, 30cm wide bottomdistance between grooves is 5.0m ditchcollecting water at the position of the foot ofthe downstream dam slope is formedtrapezoidal BxH = 0.5x0.4, slope 1: 1.0structure anhydrous stone slices, with athickness of 30cm

3 Spillway: New design Dat Doi spillway:

- Structure: Reinforced concrete M250

- Spillway width: 10,00m

- Threshold spillway have elevation: +62,50m

4 Intake: Destroy the old intake, new intake construction, behind the sewer connected to the water channel behind the main dam is connected by HDPE Þ30 pipe, the location

at the existing intake gate is of scale:

Trang 39

- Width of road surface: 3.50m

8 Ba

Gac

reservoir

- Ba Gac reservoir has a capacity of

1 Main dam

Dam crest:

dam crest width 3,90÷4,10m, Thesurface of the dam is not flat withcurrent elevation in the range+46,70÷46,90m There is no wavewall, no wheel guard, no lightingsystem Vegetation cover on the damface;

pouring: permeability coefficientexceeds the permitted level:

K=2,54E-4 cm/s ÷3,96E-3cm/s(permeability high both body Dam)

Dam slope:

is:1:1,9&1:4,0, no muscle The damslope has not been reinforced, theplants grow much

slope is 1:1,7&1:2,7, downstreamslope has muscle, width of 2.3m atelevation + 42.20m The dam slopehas not been reinforced, the plantsgrow much

- Downstream of the dam foot has a

water leak phenomenon

2 Auxiliary dam:

1 Main dam:

- Leveling creates elevation of the dam crest+46.50m; Embankment to create thedownstream slope to widen the dam crest tolên 5.0m Gia cố The main dam has a length of70.50m long with cement concrete M200, with

- Downstream slope: slope coefficient m = 1.50

và m = 2.75, Plant grass in rectangular M200concrete frame, 30cm deep groove, 30cm widebottom distance between grooves is 5.0m

ditch collecting water at the position of thefoot of the downstream dam slope is formedtrapezoidal BxH = 0.5x0.4, Slope coefficient1: 1.0, 30cm thick stone slices

from K0+15 to K0+080 (L=75m) Option ofdrill 2 buttons

2 Auxiliary dam No.1:

- Leveling creates elevation of the dam crest

Dam crest

Upstream slope

Trang 40

- Auxiliary dam No.1 have length

70m, elevation of the dam crest+45.98÷46.40m, Dam surface widthaverages 3.0m

50m, elevation of the dam crest+46,32÷46,81m, Dam surface widthaverages 3.0m

60m, elevation of the dam crest+43,74÷45,77m, Dam surface widthaverages 3.0m

40m, elevation of the dam crest+43,81÷46,02m, Dam surface widthaverages 3,5m

is: Slope coefficient of auxiliarydams1:2,0,

- Coefficient of downstream slope

status: Slope coefficient of auxiliarydams1:2,5,

- Upstream slope, downstream slope

of the Auxiliary dam has not beenreinforced

slope of the dam

3 Spillway:

- Spillway in left shoulder Auxiliary

dam No 4, Spillway width 13,0m,Threshold spillway have elevation+44,50m

- Spillway is made of stone, threshold

spillway is still relatively good indownstream spillway, trees growmuch

+46.00m; Embankment to create thedownstream slope to widen the dam crest tolên 5.0m Reinforce the dam crest, length40.0m long with cement concrete M200, with

- Downstream slope: slope coefficient m = 2.00Plant grass in rectangular M200 concreteframe, 30cm deep groove, 30cm wide bottomdistance between grooves is 5.0m ditchcollecting water at the position of the foot ofthe downstream dam slope is formedtrapezoidal BxH = 0.5x0.4, slope 1: 1.0structure anhydrous stone slices, with athickness of 30cm, Below is a reverse filterlayer consisting macadam thickness of 15cmand filtered sand thickness of 15cm Elevation

of reinforced downstream of the dam+43.00m

3 Auxiliary dam No.2&3;4:

- Leveling creates elevation of the dam crest+46.00m; Embankment to create thedownstream slope to widen the dam crest to5.0m Reinforce Auxiliary dam 2 length 30m;

Auxiliary dam 3 length 41m; Auxiliary dam 4

Downstream slope

Auxiliary dam No.1

Auxiliary dam No.2

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