Department of Alternative Energy Development and Efficiency MINISTRY OF ENERGY

Initial Environmental Examination of Khlong Ae Mini Hydropower Project Surat Thani Province Final Report (Executive Summary )

Prepared by Macro Consultants Co., Ltd.

February 2009 u5Gn u~aT~sfiorsu"a~~nu.i1"11% MACRO CONSULTANTS CO., LTD. 20 SO1 RATCHADAPHISEK 36, RATCHADAPHISEK RD. LADYAO JATUJAK BANGKOK 10900 TEL :939051 1-5,9390518-9,9391950-2 FAX :(662) 9390520 Final Report IEE of Khlong Ae Mini Hydropower Project Acknowledgement

Acknowledgement

Macro Consultants Co., Ltd. would like to express deepest gratitude to the Department of Alternative Energy Development and Efficiency for giving opportunity to jointly undertake the Initial Environmental Examination of Khlong Ae Mini Hydropower Project, Surat Thani Province.Throughout the course of study, the Consultants received excellent cooperation and support from the Project Supervisory Committee and involved DEDE’s personnel whose contributions in field survey work, sharing effort in public participation meetings as well as providing numerous constructive comments and valuable suggestions to the Consultants, are greatly appreciated. Followings are members of the Committee :

1) Khun Chavalit Jiravichailit 2) Khun Jareerat Satrawaha 3) Khun Pheeraphong Boonsang 4) Khun Wuttipong Apichonnabutr 5) Khun Praphaporn Khursida

In the course of study, the Consultants also obtained valuable secondary data with welcome cooperation from the local government agencies in Surat Thani Province namely Khlong Yan Wildlife Sanctuary, Tapee Watershed management Unit, Agriculture Office of Surat Thani, Takuk Tai Subdistrict Administrative Organization, Takuk Nua Subdistrict Administrative Organization, Num Hak Subdistrict Administrative Organization, Takuk Tai Subdistrict Health Center, Num Hak Subdistrict Health Center. In addition, during the periods of holding several public participation meetings in the local communities and the field survey work, warmest cooperation and sincere assistance were received from numerous community chiefs including the Surat Thani Associate Provincial Governor, Vibhavadi District Officer, Khiri Ratthanikhom District Officer, Prime Minister of the Takuk Tai Subdistrict Administrative Organization, Prime Minister of the Takuk Nua Subdistrict Administrative Organization and Prime Minister of the Num Hak Subdistrict Administrative Organization. The above-mentioned excellent cooperation and contributions given and helped the project study accomplished successfully are highly acknowledged.

Last but not least, special thanks is extended to Dr. Panich Pongpirodom, the Director General of DEDE who provided moral support and encouragement to the Consultants throughout the study period.

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Initial Environmental Examination of Khlong Ae Mini Hydropower Project Surat Thani Province

EXECUTIVE SUMMARY

Table of Contents Page

Transmittal Letter i Acknowledgement ii Table of Contents iii List of Figures vii List of Tables viii Abbreviation and Symbol ix

1. INTRODUCTION 1.1 Project Background and Study Objective 1 1.2 Scope of Study 3 1.2.1 Review of Previous Study Reports 3 1.2.2 Description of Existing Environmental Conditions 3 1.2.3 Assessment of Anticipated Environmental Impacts 3 1.2.4 Mitigate Measures of Adverse Impacts 4 1.2.5 Environmental Monitoring Program 4 1.2.6 Conclusion and Recommendation 4 1.2.7 Priority of Environmental Resources/Values 4 1.2.8 Public Participation and Publicity Program 4

2. REVIEW OF PREVIOUS FEASIBILITY STUDY REPORTS 2.1 Project Features and Components of Previous Study 4 2.1.1 Project Features 4 2.1.2 Project Components 5 2.2 Meteo-hydrology 6 2.2.1 Climatology and Meteorology 6 2.2.2 Rainfall 6 2.2.3 Stream Flow 6 2.2.4 Stream Flow in This Study 7 2.3 Hydropower Generation and Impact to Flow over Water Fall 7 2.3.1 Hydropower Generation 7 2.3.2 Impact to the Discharge over the Water Fall 7 2.3.3 The Study for Stopping of Hydropower Generation for 7 Some Periods of Time 2.4 Project Design 9 2.4.1 Weir and Intake Structure 9 2.4.2 Desander 9

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Table of Contents (Cont’d) Page

2.4.3 Headrace 10 2.4.4 Surge Tank 10 2.4.5 Penstock 10 2.4.6 Power House and Substation 10 2.4.7 Mechanical and Electrical Equipments 10 2.4.8 Tailrace 11 2.4.9 Access Road 11 2.5 Project Construction Cost 25 2.6 Construction and Investment plans 25 2.6.1 Construction Plan 25 2.6.2 Project Investment 25 2.7 Economic and Financial Analyses 25 2.8 Conclusion of Project Features from Update Study 27

3. EXISTING ENVIRONMENTAL CONDITIONS 3.1 Physical Resources 30 3.1.1 Weather and Meteorology 30 3.1.2 Hydrology of Surface Runoff 31 3.1.3 Surface Water Quality 31 3.1.4 Hydrogeology and Ground Water Quality 33 3.1.5 Geology and Seismology 33 3.1.6 Soil Resources 33 3.1.7 Erosion and Sedimentation 34 3.1.8 Noise and Vibration 34 3.2 Biological Resources 34 3.2.1 Aquatic Biology 34 3.2.2 Forestry Resource 35 3.2.3 Wildlife Resource 35 3.2.4 Watershed Quality Area 35 3.3 Human Use Values 36 3.3.1 Land use 36 3.3.2 Transportation 36 3.3.3 Power Supply 36 3.3.4 Water Use 36 3.3.5 Agriculture and Livestock 37 3.3.6 Fishery and Aquaculture 37 3.3.7 Irrigation 37 3.3.8 Drainage and Flood Protection 37 3.3.9 Mineral Deposit 37 3.4 Quality of Life Values 38 3.4.1 Socioeconomics 38 3.4.2 Land and Property Compensation 38 3.4.3 Public Health and Nutrition 38 3.4.4 Historic and Archeological Site 39 3.4.5 Tourist Attraction and Recreation 39

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Table of Contents (Cont’d) Page

4. ENVIRONMENTAL IMPACT ASSESSMENT 4.1 Physical Resources 40 4.1.1 Topography 40 4.1.2 Climatology and Meteorology 40 4.1.3 Air Quality 40 4.1.4 Hydrology of Surface Runoff 41 4.1.5 Surface Water Quality 41 4.1.6 Groundwater 41 4.1.7 Geology and Seismology 42 4.1.8 Soil Resources 42 4.1.9 Erosion and Sedimentation 42 4.1.10 Noise and Vibration 43 4.2 Biological Resources 43 4.2.1 Aquatic Biology 44 4.2.2 Forestry Resource 44 4.2.3 Wildlife Resource 44 4.2.4 Watershed Quality Area 44 4.3 Human Use Values 45 4.3.1 Land use 45 4.3.2 Transportation 45 4.3.3 Power Supply 45 4.3.4 Water Use 46 4.3.5 Agriculture and Livestock 46 4.3.6 Fishery and Aquaculture 47 4.3.7 Irrigation 47 4.3.8 Drainage and Flood Protection 47 4.3.9 Mineral Deposit 48 4.4 Quality of Life Values 48 4.4.1 Socioeconomics 48 4.4.2 Land and Property Compensation 49 4.4.3 Public Health and Nutrition 49 4.4.4 Historic and Archeological Site 49 4.4.5 Tourist Attraction and Recreation 49 4.5 Conclusion of Environmental Impact Assessment 50 4.5.1 Summary of direction of anticipated impacts and 50 severity degrees on the related Environmental Resources/Values 4.5.2 Priority Arrangement of Environmental Resources/Values 50

5. PROPOSED MITIGATIVE MEASURES AND MONITORING PROGRAM 5.1 Protective and Mitigate Measures 53 5.1.1 Physical Resources 53 5.2 Environmental Quality Monitoring Program 54

6. ENVIRONMENTAL ECONOMICS STUDY 56

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Table of Contents (Cont’d) Page

7. PUBLIC PARTICIPATION AND PULBIC RELATIONS 7.1 Objectives 57 7.2 Scope of Study and Study Methodology 57 7.3 Conclusion of Public Participation Meeting 59

8. CONCLUSIONS AND RECOMMENDATIONS 8.1 Summarizes the Beneficial and Adverse effects 59 8.2 Conclusions and Recommendations 61

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List of Figures Figure Page

1.1-1 Khlong Ae Mini Hydropower Project Location 2

2.2-1 Daily Flow Duration Curve 8 2.4-1 General Layout Plan Weir and Desander 12 2.4-2 Weir Sections (1) 13 2.4-3 Weir Sections (2) 14 2.4-4 Desander General Lay-Out Plan 15 2.4-5 Desander Sections (1) 16 2.4-6 Desander Sections (2) 17 2.4-7 Power Waterway Hydraulic Arrangement 18 2.4-8 Typical Section of Headrace and O&M Road Miscellaneous Details 19 2.4-9 Surge Tank Plan and Sections 20 2.4-10 Power House General Lay-Out Plan 21 2.4-11 Power House Sections 22 2.4-12 Power House Elevations 23 2.4-13 Tailrace Sections and Details 24

3.1-1 Sampling Locations of Existing Surface Water Quality and 32 Aquatic Ecology

5.2-1 Sampling Locations of Surface Water Quality and Aquatic Ecology 55 Monitoring in Khlong Ae

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List of Tables Table Page

2.1-1 Salient Features of Project of Previous Study 5 2.6-1 Project Construction Schedule 26 2.7-1 Economic Evaluation and Energy Production Cost (Discount Rate at 8%) 28 2.8-1 Salient Features of Project after Reviewed Study 29

4.5-1 Summary of Impact Assessment for Khlong Ae Mini Hydropower Project 51 4.5-2 Priority Arrangement of Environmental Resources/Values for 52 Khlong Ae Mini Hydropower Project

- viii - Macro Consultants Co., Ltd Final Report IEE of Khlong Ae Mini Hydropower Project Abbreviation and Symbols

ABBREVIATION AND SYMBOLS

ABBREVIATION DESCRIPTION

B/C Benefit-Cost Ratio DBH Diameter at Breast Height EIA Environmental Impact Assessment EIRR Economic Internal Rate of Return FIRR Financial Internal Rate of Return Hr hour IEE Initial Environmental Examination kWh Kilowatt-hour m. meter mg/l milligram per liter MPN Most Probable Number NPV Net Present Value NTU Nephelometric Turbidity Unit O&M Operation and Maintenance PCE Per Car Equivalence PCU Passenger Car Unit V/C Volume per Capacity : , / Per, Ratio

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Final Report IEE of Khlong Ae Mini Hydropower Project EXECUTIVE SUMMARY

Initial Environmental Examination of Khlong Ae Mini Hydropower Project Surat Thani Province

EXECUTIVE SUMMARY

1. INTRODUCTION

1.1 Project Background and Study Objective

The master plan study for development of Mini Hydropower project by Department of Alternative Energy Development and Efficiency (DEDE) was completed in the year B.E. 2547. The main objective of this study is to maximize the benefit from mini hydropower and also to minimize the impact of social and environmental system from this development. At the same time, the community participation is also emphasized, which is finally expected to be sustainable project. One project from this master plan study is Khlong Ae Mini Hydropower Project in Vibhavadi and Khiri Ratthanikhom Districts which is feasible to continue the study for further development.

The project features are composed of over flow weir constructed on Khlong Ae or it is called Khlong Phai by the local people. This natural channel is the boundary area between Num Hak Subdistrict, Khiri Ratthanikhom District and Takuk Tai Subdistrict, Bibhavadi District, Surat Thani Province. The other features are headrace surge tank, penstock and power house which is situated on the bank of Khlong Ae (Khlong Phai) in the area of Takuk Tai Subdistrict, Vibhavadi District, Surat Thani Province, It is shown in Figure 1.1-1

According to classification and size of Khlong Ae Mini Hydropower project, Vibhavadi and Khiri Ratthanikhom Districts, Surat Thani Province, the past study did not need to evaluate Environmental Impact Assessment (EIA) which follows the Enhancement and Conservation of Environmental Quality Act B.E. 2535 into account. But the project construction areas which are composed of storage water in front of weir, weir its self, power horse, and access road to the project areas are in Khlong Yan Wildlife Sanctuary which is the Protected Forest Area (Conservative Zone).

Therefore, the procedure before the construction, the Department of Alternative Energy Development and Efficiency which is responsible for the project, has to prepare the report of Environmental Examination of the project in order to know the environmental impact of, project procedure, project classification and features which will be the important details report to submit for asking the permission from National Park, Wildlife and Plant Conservation Department through the department’s committee. The conclusion for consideration of the study by this committee will be submitted to the cabinet for approval. If it is approved, the project development area will be withdrawed from the protected forest area.

- 1 - Macro Consultants Co., Ltd N Vibhavadi District

Takuk Nua Subdistrict

Khlong Yan Wildlife Sanctuary

Surge Tank Power House

Access Road Khlong Ae Headrace (Khlong Phai) Takuk Tai Subdistrict n

Khlong Ae Weir (Khlong Phai) Khlong Ya

Penstock Vibhavadi Waterfall #1

Khlong Yan Wildlife Sanctuary Num Hak Subdistrict

Transmission Line n Khlong Ya

Tha Khanon Subdistrict

Khiri Ratthanikhom District Scale 0.0 1.0 2.0 3.0 4.0 Km. Interconnected Point

Weir Penstock Forest Area Surge Tank Transmission Line Khlong, River Power House Access Road Vibhavadi Waterfall Headrace Khlong Yan Wildlife Sanctuary

Figure 1.1-1 Khlong Ae Mini Hydropower Project Location

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DEDE has then entrusted Macro Consultants Co., Ltd through bid tendering, to perform an Initial Environmental Examination (IEE) of the Khlong Ae Mini Hydropower Project. : 1) Previous feasibility study reports of the Khlong Ae Mini Hydropower of DEDP. The studies emphasized on the feasibility of technical, Economic and Financial and environmental aspects for the project development. In order to proceed the mini-hydropower development projects in accordance with the proposed plan, and at the same time to minimize any probable adverse impacts resulted from the project implementation. 2) Preparation of the IEE of Khlong Ae Mini Hydropower Project, format and contents as outlined by the Office of Natural Resources and Environmental Policy and Planning.

1.2 Scope of Study

The preparation of the IEE of Khlong Ae Mini Hydropower Project shall conform to the Enhancement and Conservation of National Environmental Quality Act B.E. 2535, and its format and contents as outlined by the Office of Natural Resources, Environmental Policy and Planning. Follows are major topics of the study as required in the project’s term of reference.

1.2.1 Review of Previous Study Reports

Previous feasibility study reports of the Khlong Ae Mini Hydropower of DEDP shall be reviewed and updated as appropriate.

1.2.2 Description of Existing Environmental Conditions

The preparation of the IEE of Khlong Ae Mini Hydropower Project, collect relevant data and information in order to describe existing environmental conditions at the project site, its surroundings and adjacent areas. Four aspects of environmental resources/values of interest for this study are as follows :

1) Physical Resources : comprising climatology and meteorology, surface water hydrology, surface water quality, groundwater, soil, geology and seismology, soil erosion and sedimentation.

2) Biological Resources : including aquatic ecology and fishery, forestry and wild life, watershed quality area.

3) Human Use Values : including transportation, water use, agriculture and livestock, irrigation, flood drainage and protection, minerals deposit, land use, electricity use.

4) Quality of Life Values : comprising socioeconomic status, resettlement, land and property compensation, public health and nutrition, archeological and historical sites, tourist attractions and recreation.

1.2.3 Assessment of Anticipated Environmental Impacts

Probable anticipated environmental impacts of positive, negative, direct or indirect effects would have on the environmental resources/values (ER/V) shall be described and

- 3 - Macro Consultants Co., Ltd Final Report IEE of Khlong Ae Mini Hydropower Project EXECUTIVE SUMMARY assessed in as quantified a manner as possible. Beneficial effects, which impair them, shall be evaluated both in the project’s construction and operation periods.

1.2.4 Mitigate Measures of Adverse Impacts

Appropriate and practical mitigate measures applicable for significantly adverse impacts anticipated during construction and operation periods shall be proposed as well as their estimated relevant expenditures.

1.2.5 Environmental Monitoring Program

Both short-term and long-term monitoring program shall be addressed and proposed including applicable measure and method, duration, frequency, budget, and involved regulating agencies.

1.2.6 Conclusion and Recommendation

The report shall include conclusion and recommendation from the project findings relating to prevention and mitigation measures on various aspects of environmental impacts.

1.2.7 Priority of Environmental Resources/Values

Priority setting of environmental resources/values under study shall be performed by evaluating magnitudes and severity of impacts on the affected ER/V in comparison with existing conditions of ER/V prior to project development.

1.2.8 Public Participation and Publicity Program

Publicity programs and local population involvement on the project development shall be performed through joint meeting with local residents and organizations not less than 3 occasions. Particular attention shall be paid to the local communities situated within the 3-10 kilometer radius distance from the project site, and also the communities located 3-10 kilometers away surrounding the project site. Their attitudes, comments, pattern of local resident involvement, and recommendation as well as from local non-government organizations and local administration organizations, shall be assessed and included in a separate report other than the project main report.

2. REVIEW OF PREVIOUS FEASIBILITY STUDY REPORTS

2.1 Project Features and Components of Previous Study

2.1.1 Project Features

Khlong Ae Mini Hydropower Project is a pondage run-off-river type. Construction of a concrete weir creates a small reservoir enough to generate electricity during peak-load hours at least 4 hours a day by daily regulation. When available daily inflow is more than the capacity of the reservoir, more hours of electricity generation can be made up to 24 hours with full capacity of the power plant. The water excess the design discharge of the power plant will be spilled over the weir to downstream.

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2.1.2 Project Components

The results from the update on Feasibility Study and Solicitation Document for Investment in 4 Mini Hydropower Projects : Khlong Ae Mini Hydropower Project (DEDE 2006) as presented in Table 2.1-1

Table 2.1-1 Salient Features of Project of Previous Study

No. Items

1. Project type : Pondage 2. Catchment Area : 30.1 km2 3. Hydrology - Average Annual Inflow 26.05 MCM - Flood Design (10 years Flood) 215.8 0 m3/sec - Annual Sedimentation 3,653 m3 4. Weir - Type Ogee Weir Concrete Gravity - Weir Crest +320.00 mMSL - Length 35.00 m - Height 7.00 m - Normal Height Water Level +320.00 mMSL - Minimum Water Level +318.00 mMSL 5. Headrace - Type Steel Pipe with Reinforced Concrete - Diameter 1.00 m - Length 2,060 m 6. Intake Structure - Type Reinforced Concrete Structure - Intake Crest Elevation +315.00 mMSL 7. Surge Tank - Type Steel Tank - Height 15.00 m - Diameter 4.00 m - Base Elevation +310.50 mMSL 8. Penstock - Type Steel Pipe - Diameter 0.80 m - Length 873 m 9. Power House - Type Reinforced Concrete Structure - Diamension 18.00x37.00 m

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Table 2.1-1 (Cont’d) Salient Features of Project of Previous Study

No. Items 10. Turbine - Type Pelton - Design Discharge 2x0.57 m3/s - Design Head 188.97 m - Installed Capacity 2x905 kW 11. Generator - Output Capacity 2x1,065 kWA - Power Factor 0.85 Transmission Line - Number of Circuit 1 Circuit - Voltage 33 kV - Distance 18.00 m Average Annual Energy 10.96 GWh

Source : DEDE, 2006

2.2 Meteo-hydrology

2.2.1 Climatology and Meteorology

The climate of the Tapi river basin is influenced by South-west and North-east monsoons which can be divided into two seasons. Rainy season usually starts from middle of May to December which can be divided into two parts. The first part is from May to October which is influenced by South-west monsoon while the second part is from November to December. And the summer starts in January and is ended in April.

2.2.2 Rainfall

The thirty years of mean monthly rainfall data from the years B.E. 2517 to 2546 of the selected rainfall station by thiessen polygon reveals that in the area of lower Poomduang tributary in which the project is situated, the mean monthly rainfall is 2071.1 mm. and can be divided into 1,853.9 mm in the wet season (May to December) and 222.2 mm. in the dry season (January to April).

2.2.3 Stream Flow

The project area is situated in Lower Poomduang tributary with the catchment area of 2,012.96 km2. The mean annual stream flow data of the whole tributary is 2,191.21 million cubic meter or the annual stream flow over one square kilometer of the catchments area is 34.52 litres/sec/km2.

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2.2.4 Stream Flow in This Study

There is no stream flow gauging station at weir location, therefore, stream flow of near by station or the index station is used to analyse in the form of regional analysis in order to calculate the factor for transferring the stream flow of the near by station to the weir location. The results of evaluation of monthly flow at weir location from the year B.E. 2516-2547 are varying between 0.71-3.85 million cubic meter and the mean annual stream flow is 25.75 million cubic meter.

The result for calculation of flow-duration curve at weir location for being used in planning and design of mini hydropower generation is shown in Figure 2.2-1.

The mean annual maximum stream flow at weir location and at power house with catchment area of 30.1 and 32.2 square kilometers are 34.6 and 37.0 cubic meters per second respectively.

2.3 Hydropower Generation and Impact to Flow over Water Fall

2.3.1 Hydropower Generation

The result of the study by the Department of Alternative Energy Development and Efficiency (DEDE) in the year 2549 revealed that the alternative with the power installed capacity of 1,810 kW., the design discharge of 1.14 cms. (20% of time equaled or exceeded) and the design head of 188.97 m. with corresponding to power out put of 10.96 million unit per year is the best alternative with EIRR of 8.73%

2.3.2 Impact to the Discharge over the Water Fall

The project with the catchment area of 30.1 km2., during low flow, water can be accumulated in front of weir up to minimum flow for hydropower generation (0.342 cms.) or up to the maximum flow for power generation (1.14 cms.). From 22 years of (B.E 2526 to 2547) monthly flow data collection at Khlong Ae Mini Hydropower project reveals that minimum flow taken place in both February and April months of the year B.E 2533 and are equal to 0.14 and 0.15 million cubic meter per month respectively.

In the case of with project, the number of days without water flowing over the water fall should be increased and might be closed to 20% of time equaled or exceeded.

2.3.3 The Study for Stopping of Hydropower Generation for Some Periods of Time

Khlong Ae Mini Hydropower project is diverted the water by pass the water fall for power generation. Therefore the study of alternatives for stopping of hydropower generation for some periods of time is made. The stopping of hydropower generation is usually made during the day time of the tourist season. Four alternatives have been discussed and can be concluded in the following table.

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ชวงเวลาการเกTime ิด ปรDailyิมาณน ้ําทFlowารายว (cu.m./sec)ัน (ลบ.ม./วินาที)

% nd st (%) ผลการศ2 ึกษาครStudyั้งที่ 2 ผลการศ1 ึกษาครStudyั้งแรก 9 1 5.63 6.30 5 2.54 2.65 10 1.78 1.70 15 1.39 1.25 20 1.14 1.00 8 25 0.95 30 0.81 0.80 35 0.69 40 0.60 0.60 45 0.53 7 50 0.47 0.50 55 0.42 60 0.36 0.45 65 0.31 70 0.26 0.38 6 75 0.22 80 0.18 0.30 85 0.15 90 0.12 0.20 95 0.08 100 0.02 0.15 5

ผลการศ2nd Studyึกษาครั้งที่ 2 4 ผลการศ1st Studyึกษาครั้งแรก Daily Flow (cu.m./sec) . Daily Flow (cu.m./sec)

3

2

1

0 0 102030405060708090100 Time (%)

Figure 2.2-1 Daily Flow Duration Curve

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Hydropower Case Details Generation Output million unit per year

1. Four months during tourist period, stop of hydropower 7.75 generation for 12 hrs daily during the day time, while the rest of 188 days stop of hydropower generation for 7 hrs. daily during the day time. 2. Four months during tourist period, stop of hydropower 7.97 generation for 12 hrs. daily during the day time while the rest of 188 days stop of hydropower generation for 6 hrs daily during the day time 3. Four months during tourist period, stop of hydropower 7.90 generation for 11 hrs. daily during the day time, while the rest stop of hydropower generation for 7 hrs. daily during the day time 4. Four months during tourist period, stop of hydropower 8.11 generation for 11 hrs. daily during the day time, while the rest stop of hydropower generation for 6 hrs. daily during the day time.

Remark : In average case, 15% of the time or 55 days in a year, full capacity of hydropower installed can be generated with minimum flow over water fall of 0.25 cms. Which is in wet season period.

2.4 Project Design

In this study, it was considered by the consultant that the project features which had been preliminary designed by the Department of Alternative Energy and Efficiency is suitable and the details are:

2.4.1 Weir and Intake Structure

1) Weir. It is a reinforced concrete overflow weir with ogee crest. The height is 7.00 m and the crest level is at 320.00 m.MSL. The crest length is 35 m while the river bed level is 313.m.MSL. The sand sluice has three gates and it is joined by reinforced concrete bridge mainly for maintenance purpose. The 100-yrs. flood magnitude is 215.80 cms. (Figure 2.4-1 to Figure 2.4-3)

2) In take structure. It is reinforced concrete structure and is located on left bank of the weir. The floor elevation is 315.00 m.MSL. The size of sluice gate is 1.00x1.20 m. Trash rack is also installed in order to protect garbage flowing into Intake Conduit.

2.4.2 Desander

Desander is a reinforced concrete structure. The width and length are 3.50 m. and 44 m. respectively. The main features are:

1) Sand Trap. It is reinforced concrete structure and is composed of sand sluice with enough length for sand deposited.

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2) Spillway. The flood flows over this channel. 3) By Pass Channel. It is reinforced concrete flow channel and is operated when maintenance of Sand Trap and Sand Sluice are needed. (Figure 2.4-4 to Figure 2.4-6)

2.4.3 Headrace

Headrace of this project is designed as box culvert or conduit with diameter of 1.00 m. covered with reinforced concrete with the length of 2,060m. O&M road with 3.50 m. width is constructed parallel to Headrace line from upstream weir to power house with the length of 2,000 m. (Figure 2.4-7 to Figrue 2.4-8)

2.4.4 Surge Tank

Surge Tank of this project is the steel structure and is simple Surge Tank with 4.00 m. diameter and is 15.00 m. high. Surge Tank foundation is hard rock. Elevation of surge tank is 312.00 m.MSL. (Figure 2.4-7 and Figrue 2.4-9)

2.4.5 Penstock

Penstock is high pressure pipe with 0.80 m. diameter and is received water from Surge Tank to Power House. It is laied down on the pier and is fastened with anchor block at the curve point. Penstock is designed against the pressure from water hammer with the length of 873 m. (Figure 2.4-7)

2.4.6 Power House and Substation

1) Power house. It is reinforced concrete structure with the size of 18.00 x37.00 m. The level of power house and substation is at 132.50m.MSL.(Figure 2.4-10 to Figure 2.4-12) 2) Substation. It is an open type reinforced concrete structure with the size of 8.00x11.00 m.

2.4.7 Mechanical and Electrical Equipments

1) Turbine. The selection of size and type of turbine depends mainly on Head and Discharge. The suitable turbine features can be concluded as follows:

Type of Turbine : Horizontal Shaft Pelton Turbine Number : 2 sets Design discharge : 2x0.57 cms. Head : 188.97 m. Power generation for 1 set : 905 kilowatts Total power generation : 2x0.905 megawatts Speed : 1,000 revolutions per minute

2) Generator Type : 3 Phase, A.C. synchronous Speed : 1,000 revolutions per minute Voltage : 3.3 Kilovolts Power factor : 0.85 Frequency : 50 Hz.

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3) Transformer Type : Outdoor, Two-winding, 3 phase, Power Transformer Voltage : - Low voltage 3.3 Kilovolts - High voltage 33 kilovolts - Off-Load Tap + 5% Frequency : 50 Hz. Connecting : Delta/wye Grounded Heat released system : Oil-immersed/self-cooled

4) Transmission Line. Transmission line from Khlong Ae Mini Hydropower Project is connected with the system of Non-metropolitan Electricity Authority of Thailand (NEA) in Khiri Ratthanikhom District area, Surat Thani Province.

Length : 18 km. Voltage : 33 Kilovolts Size of transmission line : 120 square millimeters Electrical pole : Improved strength concrete pole, NEA Standard Surge Arrester : Close to power transformer

5) Ground Line and Protection system. Out side frame of electrical equipments which might be contacted, should not have electrical power flowing. In order to protect the danger, they should have ground system. Size of ground line depends on size of protection equipments for that circuit.

6) Equipment for Measurement on Working. Necessary measurement equipments for working in Hydropower Plant are: - Voltmeter - Ammeter - Frequency meter - Wattmeter - Kilowatthour meter - Var meter - Speed meter - Synchroscope

2.4.8 Tailrace

Tailrace is reinforced concrete structure and the level is 130.50 m.MSL. The design discharge is 1.14 cms. (Figure 2.4-13)

2.4.9 Access Road

1) Access road to headwork. It is paved with asphalt and is double surface treatment (DBST). Width and length are 4.00 m. and 1,635 m. respectively. 2) O & M road. It is constructed parallel to headrace and penstock for maintenance purpose. Road surface is single surface treatment with 3.5 m. width.

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Final Report IEE of Khlong Ae Mini Hydropower Project EXECUTIVE SUMMARY

2.5 Project Construction Cost

The construction cost of Khlong Ae Mini Hydropower Project, Surat Thani province, is estimated at 286.16 million Baht and is the year B.E. 2551 cost. It can be separated according to type of works namely:

1) Preparation and Civil works 161.15 million Baht 2) Hydraulic equipment 38.47 million Baht 3) Electrical and Mechanical equipments 68.24 million Baht 4) High Voltage Transmission Line 17.97 million Baht

2.6 Construction and Investment plans

2.6.1 Construction Plan

The construction of Khlong Ae Mini Hydropower Project, Surat Thani Province is scheduled for 36 months period and is shown in Table 2.6-1.

2.6.2 Project Investment

There may be two possibilities for project investment namely:

1) Investment by the government. The full project is invested by the government. The procedure, communication and coordination in order to get the certificate asking for permission to use the construction area and so on will be convenient. But during carrying on the project procedure, it might be allowed the private organization for rental project. This will reduce the risk for uncertainty of investment during carrying on the project.

2) Concession to private organization. It might be arrangement in the form of BTO (Build-Operate-Transfer). Private organization is invested, design and construction of the project. When the project construction is completed. It will be transferred to the government but private organization still be responsible for administration during concession period. In this case, government responsible office can be coordinated with the government office concerned in order to make the project construction possible. This type of concession will be benefit to the government namely: purchase the electricity with reseasonable price without project investment, increase the efficiency of power generation and quality of electricity service, and reduction of the government responsibility.

2.7 Economic and Financial Analyses

Khlong Ae Mini Hydropower Project is designed to bypass the water from Vibhavadi water fall for hydropower generation. This will reduce the flow rate at water fall, which will impact to the tourist at Vibhavadi water fall area. In order to solve this problem, it is recommended to stop the hydropower generation for some periods of time especially during the day time of tourist season. Four alternatives to stop the power generation have been studied and are concluded in item 2.3-3.

- 25 - Macro Consultants Co., Ltd Table 2.6-1 Project Construction Schedule

No. Items Year 1 Year 2 Year 3 123456789101112123456789101112123456789101112 1. Preparatory Works

2. Project Construction

2.1 Diversion Works

2.2 Weir and Intake Structures

2.3 Sedimentation Pond

2.4 Headrace Works

2.5 Surge Tank

2.6 Penstock

2.7 Powerhouse and Tailrace - 26 2.8 Transmission Line

3. Electro-Mechanical Works

3.1 Turbine and Generator

3.2 Installation

4. Test and System Commissioning Final Report IEE of Khlong Ae Mini Hydropower Project EXECUTIVE SUMMARY

Hydropower generation of four alternatives have been analysed in order to get the economic index of hydropower investment and is shown in Table 2.7-1. The result of analysis reveals that EIRR is varying between 6.82-7.29 % in which the economic rate of return is higher than the present government bond (the present government bond is 5-6%). It may be concluded that the project is economic feasible. Although the hydropower generation will be lower than the target (without stop of hydropower generation). While the investment cost of power is in the order of 3.18-3.33 Baht/kilowatt, which is not in the high side when it is comparing with electricity generated by fossil fuel. And it is expected that the price of fossil fuel will be higher in the future with following by higher investment cost for electricity power generation.

2.8 Conclusion of Project Features from Update Study

Khlong Ae Mini Hydropower project will be constructed on the stream with very steep slope portion by diversion of water from the upstream of very steep slope to by pass the steep portion through pipe and penstock to generate the power at power house which is constructed at the downstream end of this steep slope portion. The project features are composed of weir height of 7 m. and 35.00 m. of crest length will be constructed on Khlong Ae. Between water level of 318.00 m. MSL to 320 m.MSL in front of weir will be a storage of water of 60,100 cubic meters. This volume is used to store water during minimum flow period in order to supply power to the system during peak load. Water is diverted by weir through 1.00 m pipe diameter with the length of 2,060 m., then water is diverted to penstock and finally to power house which is constructed on river bank downstream. Minimum flow which can be generated the power is 1.14x0.30 = 0.342 cms. The water passing through turbine at power house is then released to Khlong Ae downstream of steep portion through energy dissipater in order to protect erosion on Khlong Ae downstream of power house. The important project features from update study can be summarized in Table 2.8-1.

- 27 - Macro Consultants Co., Ltd Table 2.7-1 Economic Evaluation and Energy Production Cost (Discount Rate at 8%)

Item NPV B/C EIRR Energy Production Cost % Baht/kWh Alternative 1 (a) Base Case -24.49 0.91 6.82 3.33 (b) Sensitivity Analysis * - Case 1 -38.38 0.87 6.23 - Case 2 -37.16 0.87 6.2 - Case 3 -51.06 0.83 5.64 Alternative 2 (a) Base Case -18.56 0.93 7.11 (b) Sensitivity Analysis * - Case 1 -32.46 0.89 6.51 3.23 - Case 2 -31.53 0.77 6.48 - Case 3 -45.43 0.84 5.91 Alternative 3 (a) Base Case -20.70 0.93 7.00 3.26 (b) Sensitivity Analysis * - Case 1 -34.60 0.88 6.41 - Case 2 -33.56 0.88 6.38 - Case 3 -47.46 0.84 5.82 Alternative 4 (a) Base Case -14.87 0.95 7.29 3.18 (b) Sensitivity Analysis * - Case 1 -28.77 0.90 6.69 - Case 2 -28.03 0.90 6.66 - Case 3 -41.92 0.86 6.08

Remarks : Case 1 : Invesment Increased 5% from Base Case Case 2 : Benefit Decreased 5% from Base Case Case 3 : Invesment Increased 5% and Benefit Decreased 5%

- 28 - Final Report IEE of Khlong Ae Mini Hydropower Project EXECUTIVE SUMMARY

Table 2.8-1 Salient Features of the Project after Reviewed Study

No. Items

1. Project type : Pondage 2. Catchment Area : 30.1 km2 3. Hydrology - Average Annual Inflow 26.05 MCM - Flood Design (10 years Flood) 215.8 0 m3/sec - Annual Sedimentation 3,653 m3 4. Weir - Type Ogee Weir Concrete Gravity - Weir Crest +320.00 mMSL - Length 35.00 m - Height 7.00 m - Normal Height Water Level +320.00 mMSL - Minimum Water Level +318.00 mMSL 5. Headrace - Type Steel Pipe with Reinforced Concrete - Diameter 1.00 m - Length 2,060 m 6. Intake Structure - Type Reinforced Concrete Structure - Intake Crest Elevation +315.00 mMSL 7. Surge Tank - Type Steel Tank - Height 15.00 m - Diameter 4.00 m - Base Elevation +310.50 mMSL 8. Penstock - Type Steel Pipe - Diameter 0.80 m - Length 873 m 9. Power House - Type Reinforced Concrete Structure - Diamension 18.00x37.00 m 10. Turbine - Type Pelton - Design Discharge 2x0.57 m3/s - Design Head 188.97 m - Installed Capacity 2x905 kW

- 29 - Macro Consultants Co., Ltd Final Report IEE of Khlong Ae Mini Hydropower Project EXECUTIVE SUMMARY

Table 2.8-1 (Cont’d) Salient Features of the Project after Reviewed Study

No. Items

11. Generator - Output Capacity 2x1,065 kWA - Power Factor 0.85 Transmission Line - Number of Circuit 1 Circuit - Voltage 33 kV - Distance 18.00 m - Annual energy 8.11 GW.h 12. Project construction 36 months 13. Project Period 50 years 14. Total Project Construction Cost 286.19 million Baht 15. Economic Evaluation - NPV -14.87 million Baht - B/C 0.95 - EIRR 7.29 % - Energy Production Cost 3.18 Baht/kWh

3. EXISTING ENVIRONMENTAL CONDITIONS

As the project area is situated in Protected Forest Area as well as the Khlong Yan Wildlife Sanctuary, the National Park, Wildlife and Plant conservation Department does not allow the study and research team to work in the project area. However, from the coordination with Khlong Yan Wildlife Sanctuary Office, the working team could have their officers to take care during the preliminary study of the project construction area. It is found that the construction area in Khlong Yan Wildlife Sanctuary which is the edge area in the east is similar to the vicinity area around the outside Wildlife Sanctuary area. Therefore in this study, the survey and data collection of environmental quality have been made on the vicinity area outside the Khlong Yan Wildlife Sanctuary area in stead of the inside area.

3.1 Physical Resources

3.1.1 Weather and Meteorology

The weather in Khlong Ae Mini Hydropower Project Vibhavadi district, Surat Thani province is influenced by monsoon and storm namely:

1) South-west monsoon: starts in May until October. 2) North-east monsoon: starts in the beginning of November until January. 3) Typoon from South Chin Sea: it is in the period of November to December.

The data from weather station at Surat Thani Province airport of 30 years (B.E. 2514- 2543) period reveals that the mean annual rainfall is 1519.80 mm., while the mean annual

- 30 - Macro Consultants Co., Ltd Final Report IEE of Khlong Ae Mini Hydropower Project EXECUTIVE SUMMARY number of days are 146.60. The heavy rainfall of 244.30-302.10 mm. is in October and November months. The daily maximum and minimum rainfall of 366.80 mm. and 45.80 mm. are in November and January months respectively, while the annual thunder storm takes place in 63.50 days.

3.1.2 Hydrology of Surface Runoff

The topography of the project location area is in the hilly area and is covered with mixed forest. The height of mountain is varying from lower than 100 m.MSL to higher than 600 m.MSL. The highest mountain is called “Kaosoong” which is the beginning of “Khlong Ae” or the local name is “Khlong Phai”. It is about 7 km. away in the west direction from the location of water diversion weir and the height is 1,007 m.MSL.. Khlong Ae (Khlong Phai) is originated from two natural channels namely: Khlong Bangtapien and Khlong Phai. They are flowing to meet each other about 2 km. before arriving the weir location. The catchment area of Khlong Ae is about 30.1 km2. with the length of 7 km.. The water in the catchment area flows from the west to the east direction. The mean daily maximum and minimum flow at weir location from the year B.E. 2516 to 2546 are in the following table:

Unit : million cubic meter Apr. May Jun. Jul. Aug. Sep. Oct. Nov. Dec. Jan. Feb. Mar. Ann. Avg. 1.15 1.76 1.68 2.11 3.19 3.21 3.45 3.91 2.92 1.20 0.71 0.77 26.05 Max. 6.88 6.97 6.82 8.43 10.04 6.57 10.87 14.77 20.34 3.86 3.57 3.59 50.25 Min. 0.12 0.26 0.51 0.47 0.47 1.30 0.93 1.11 0.53 0.26 0.14 0.14 9.08

Remark: Ann. means annual.

3.1.3 Surface Water Quality

The major analysis result of grabbed water from 5 stations in Khlong Ae (Khlong Phai) as locations shown in Figure 3.1-1 on May 12, 2008 (in Dry Season) and October 1, 2008 (Wet Season) can be summarized in the following Table

Station SW1 Station SW2 Station SW3 Station SW4 Station SW5 Parameter May Oct. May Oct. May Oct. May Oct. May Oct. 2008 2008 2008 2008 2008 2008 2008 2008 2008 2008 DO (mg/l) 7.8 8.0 6.6 8.5 8.3 8.1 7.2 8.4 4.7 7.6 BOD (mg/l) 5.5 0.8 3.6 0.6 6.8 0.1 2.0 0.8 4.0 0.4 FCB (MPN/100 ml) 3,300 1,100 1,400 4,900 490 1,300 2,300 7,000 1,300 330 TCB (MPN/100 ml) 3,300 4,600 1,400 130,000 7,900 240,000 2,300 33,000 3,300 1,100

In dry season, the quality is in typical range of natural water the southern region. It is remarkable for the high BOD at all stations as the influence from the Burma Cyclone (Nargis) during April-May 2008. The heavy rain flushed out organic matter from sloping area into Khlong Ae. High contents of coliform bacteria (FCB, TCB) also represent the contamination of community wastewater as there are agriculture community upstream and downstream of the weir site. Apart from that, a lot of tourists at the waterfall site also create community wastewater into Khlong Ae.

However, the continuous flow of water can create assimilative capacity of the water so that the overall surface water quality of Khlong Ae is still in Class 2 or very clean fresh

- 31 - Macro Consultants Co., Ltd SW 1 N

SW 2

Power House คลองแอะ Surge Tank SW 3 Takuk Tai Subdistrict

Khlong Ae SW 1 (Khlong Phai) SW 3 Weir Khlong Ae SW 4 SW 2 SW 4 SW 5 (Khlong Phai)

Vibhavadi Waterfall #1 Num Hak Subdistrict SW 5

Scale

0.0 1.0 2.0 3.0 4.0 Km.

Legend : Forest Area Weir Penstock Khlong, River Surge Tank Transmission Line Vibhavadi Waterfall Access Road Khlong Yan Wildlife Sanctuary Power House Headrace Water Sampling Point

Figure 3.1-1 Sampling Locations of Existing Surface Water Quality and Aquatic Ecology

- 32 - Final Report IEE of Khlong Ae Mini Hydropower Project EXECUTIVE SUMMARY surface water resources used for consumption, aquatic conservation, fisheries, recreation and consumption which requires ordinary water treatment process.

3.1.4 Hydrogeology and Ground Water Quality

The hydrogeological characteristic in Khiri Ratthanikhom District and Vibhavadi District consists of sedimentary rock in Quaternary Age. The consolidated aquifers provides ground water at yield lower than 2 m3/h.

In Kiri Ratthanikhom District, the unconsolidated aquifer consists of Alluvium and Colluvium deposits while the consolidated aquifer consists of Sedimentary Rock, semi- Sedimentary and Metamorphic Rock, and Igneous Rock.

In Vibhavadi District, the unconsolidated aquifer is of Colluvium deposits while the consolidated aquifer consists of Sedimentary Rock, Semi-Sedimentary Rock, Metamorphic Rock, and Igneous Rock.

3.1.5 Geology and Seismology

At weir site, the topography is narrow valley at average height of 320 m.MSL. The geologic formation is of thick deposit soil on both sides at average thickness 4-8 m covered with Alluvium Deposits, stationary accumulates and traces of colluvium soils and rocks. Most soils are clay of sandy clay, gravelly clay and silty clay. The weir foundation is of Biotite- Muscovite Granite with coarse grained and porphyritic textures that can be seen along both banks of Khlong Ae. The strength of granite rock is high with low permeability, except that some can be leaked in the zone of weathered granite.

The granite foundation layer at weir site is 4-5 m from ground surface level. It is typically fresh granite with low permeability and high strength.

The ground water table at weir site is nearly the same as Khlong Ae surface water level, ie, 1.5 m from ground level at the banks and 7.8 m at higher sloping area. The environmental status of upstream water storage consists of thick forest without rocks in sight. The geology upstream is covered with colluvium soil. The rock under water storage is granite without large faults. No leakage is expected as it is covered with very thick soil layers. The soil erosion in the storage zone will not be serious as it is plain with low slope and covered with thick trees.

Surat Thani Province locates in the Zone 2A of the Earthquake Risk Classification according to the revised Earthquake Map of DMR falls in severity range V-VII Mercalli. It means that small to medium risk degree of damages can occur if the construction is poor.

3.1.6 Soil Resources

The soil at proposed Khlong Ae Power House site and its vicinity is mostly of slope complex unit (SC) up to 81.70%. The rest 18.29% is Thung Wa and Khlong Nok-Krathung soil (Tg & knk) and 0.02% is Khlong Teng/ Na Thon/ Huai Yot association (Klt/ Ntn/ Ho), respectively.

- 33 - Macro Consultants Co., Ltd Final Report IEE of Khlong Ae Mini Hydropower Project EXECUTIVE SUMMARY

Analytical data of slope complex unit (SC) soil indicates medium to low fertility. However, the shallow soil layer is not suitable for agricultural used. The soil is currently covered with many forest types and should be kept for watershed areas.

Evaluation of soil erosion in the Power House and its vicinity area indicates the soil erosion of very severe (soil lose 15-20 ton/rai/year) to extremely severe (soil lose more than 20 ton/rai/year). However, the soil erosion rate is depended on the existing land use types.

3.1.7 Erosion and Sedimentation

The result of annual suspended load study at weir location with the catchment area of 30.1 km2 is 3,541 tons. In bed load analysis, the bottom sediments is assumed to be 30 percent of the suspended load which is equal to 1,062 tons. Therefore the total annual sediment load at weir location is 4,603 tons. If the specific weight of sediment is assumed to be 1.26 tons/cubic meter, then the erosion rate of catchment upstream of the will be 0.121 mm./year.

3.1.8 Noise and Vibration

The project components will be constructed in the Khlong Yan Wildlife Sanctuary area while the hydropower plant locates near the office of Tapee Watershed Management Unit and the office of Khlong Yan Wildlife Sanctuary. The nearest community consists of a house and a small resort on the road to the east dierction at 400 m far from the project area. The community of Ban Wang Phakwaen is further. However, there are no important noise sources at the present time.

3.2 Biological Resources

3.2.1 Aquatic Biology

The sampling of aquatic organism was done at 5 stations during dry and wet seasons at the same stations as those of surface water quality. The results can be concluded as.

Phytoplankton : 36 species were found in dry season. They were in 3 divisions, 4 classes at density 31,647-41,586 Units/m3. 23 species were found in wet season. They were in 3 divisions, 3 classes. The species diversity indicates moderate fecundity. Zooplankton : 15 species were found in dry season. They were in 3 phylums, 4 classes at density 20,580-24,232 Units/m3. 9 species were found in wet season. They were in 3 phylums, 4 classes at density 9,814-16,074 Units/m3. The species diversity index indicates moderate fecundity in dry season and low fecundity in wet season. Benthos : 7 species were found in dry season. They were in 2 phylums, 2 classes, 4 orders with 22-396 Units/m3. 14 species were found in wet season. They were in 2 phylums, 2 classes, 6 orders with 242-814 Units/m3. The species diversity index indicates rather low fecundity. Fish : 44 species in 17 families were found. The 117 species of Cyprinidea Family is most commondly found. Most fish survives in flowing water rather than stagnant water. Weeds : 10 species in 10 families of weeds along the bank were found. Flowing weeds were not found.

- 34 - Macro Consultants Co., Ltd Final Report IEE of Khlong Ae Mini Hydropower Project EXECUTIVE SUMMARY

3.2.2 Forestry Resource

The ecology in project area is evergreen forest in the Khlong Yan Wildlife Sanctuary. Various Horticulture trees in Dipterocarpaceae Family are found in the locations of weir, headrace, surge tank and penstock at density 20-46 Units/Rai. The power plant locates on flat area along Khlong Ae. The major tree found is Dipterocarpus turbinatus Gaertn.

3.2.3 Wildlife Resource

By data collection and walking survey in August and November 2008 during day time in the project area together with information from visited villagers, the 168 wildlife species in 26 orders, 71 families and 129 genus were found as the following conclusion :

Number (accoding to Taxonomic Classification) Type of Wildlife (Order) (Family) (Genus) (Species) Amphibians 1 5 8 12 Reptiles 2 10 23 28 Avis 14 42 77 105 Mammals 9 14 21 23 Total 26 71 129 168

The legal protection status of these 168 wildlife species are as follow :

Total Number of species according to 2535 Act and 2546 Law Type of Wildlife Species Reserved Protected Non-Protected Animals Animals Animals Amphibians 12 - 2 10 Reptiles 28 - 12 16 Avis 105 - 103 2 Mammals 23 - 13 10 Total 168 - 130 38

Checking with the lists of OEPP (B.E.2540) and IUCN (2007), there are 8 species that counted in the list of Near Threatened, “Vulnerable” and “Endangered”.

3.2.4 Watershed Classification

According to the OEPP Watershed Quality Boundary Map, the project components will be located in Watershed Quality Class 2, 3 and 4 with no disturbance to watershed Quality 1A, 1B.

The land use suggestion for Watershed Quality Class 2 in southern watershed area is for forestry, mining, Para Rubber plantation or other activities related to the national economic and security with confirmation from responsible agencies that the project cannot avoid using the area or move to other area. Strict monitoring according to the government regulations must be applied in order to protect the watershed and downstream areas.

- 35 - Macro Consultants Co., Ltd Final Report IEE of Khlong Ae Mini Hydropower Project EXECUTIVE SUMMARY

3.3 Human Use Values

3.3.1 Land use

As the study area is located in the conservation zone of Khlong Yan Wildlife Sanctuary, the area mainly covers with natural forest. The land use data in 2007 of the weir site and its vicinity indicated that the evergreen forest is the main land use (43.27%) followed by agricultural land used (para rubber plantation, oil palm plantation and mixed orchard), deteriorate forest, economic forest area, urban areas and government official areas (Khlong Yan Wildlife Sanctuary office and Ta Pee Watershed Management Unit area), which is 38.47%, 8.91%, 8.20%, 0.61% and 0.54% respectively.

3.3.2 Transportation

Transportation to the project site is to go along Provincial Highway 4247 from Khiri Ratthanikhom District for 1.5 km. Then, turn left on Surat Thani PAO Road, Ban Yang- Takuk Nua, that link highway 4247 and 4262 to northward direction passing communities of Ban Yang Subdistrict until reaching Ban Pak Phai, Nam Tak Subdistrict, total distance 17 km. After that, turn left along Rural Highway 3176 (Ban Pak Phai-Ban Nam Tak Vibhavadi) for 8 km to reach the power plant site in the area of Tapee Watershed Management Unit.

Another route can also reach the project site by starting from Ban-Yang-Takuk Nua Road at Vibhavadi District to the same route as mentioned above.

The three main roads are asphalitic two-traffic lanes of which traffic volumes are low.

3.3.3 Power Supply

The project area electricity service is under the responsibility of PEA Branch Office at Khiri Ratthanikhom District. The maximum electricity demand in 2007 of both districts in the project area is 3.5 MW . Up to 30% of power supply serve the commercial business and industry while the rest 70% serve households. The demand in year 2005, 2006 and 2007 are 26.223, 27.959 and 30.631 million units, respectively. The forecast demand by the end of year 2008 is 34.293 million unit at annual growth rate 10%. So, the expected electricity demand by next 10 years (2018) will be around 87.394 million units.

The household electricity consumption reveals that 60 out of 1,046 householes in Nam Hak Subdistrict (or 5.74%) have no electricity service. Even worse, 359 out of 3,030 householes in Takuk Nua Subdistrict (or 11.85%) and 38 out of 1,085 households in Takuk Tai Subdistrict (3.5 %) also have no electricity.

The feedbacks from people concerning electricity service is the frequently black out problem, especially in wet season, that can damage their electrical appliances.

3.3.4 Water Use

The sources of water use in the project area are as follow : consumable water (drinking cooking ) from rain water and bottled water; cleaning and other types of water use

- 36 - Macro Consultants Co., Ltd Final Report IEE of Khlong Ae Mini Hydropower Project EXECUTIVE SUMMARY from natural canal, shallow wells or village piped water. The project site located at Ban Wang Phakwaen which has a village pipe water supply system using raw water from Khlong Ae by constructing intake and pipeline conveying water from Vibhavadi Waterfall to every household free of charge. The pipeing is also expanded to nearby villages of Ban Chiao Maprang at fair charging rate.

There is no water usage from large industries in the project area. The agriculture water usage is mostly from rain water.

3.3.5 Agriculture and Livestocks

The agricultural sector in the study area plays a considerable social, political and economic role. In order to achieve the existing land use data of the study area, land use map in 2007 were analyses. The main agricultural land use area is for para rubber plantation which covers 13,638 rai or 27.92%. This is followed by oil palm plantation (2,130 rai or 4.36%), mixed area of para rubber plantation and oil palm plantation (2,948 rai or 6.04%), mixed area of oil palm and mixed orchard (71 rai or 0.15%) and mixed area of mixed orchard and urban area (299 rai or 0.61%). The mixed orchard (fruit trees) in the study area are mainly rambutan, durian, mangosteen, pomelo and banana

In the study area, the main livestocks is oxen which can be found up to six small farms. The 21 oxen are fostered in para rubber plantation areas. The pasture normally growth between para rubber rows. Other livestocks are of minimal such as the domestic fowl which is normally found in the study area.

3.3.6 Fishery and Aquaculture

The village leaders inform that fishing is only for household consumption and the quantity of fishing products depends on seasonal conditions. No commucial is applied as Khlong Ae is quite shallow in dry season with low fish abundance.

3.3.7 Irrigation

There is no development of irrigation system in the study area. From the 1:50,000 contour map scale of the Army Map Department, the downstream area on both banks of Khlong Ae (Khlong Phai) is mostly rolling area with steep slope with no symbol of paddy.

3.3.8 Drainage and Flood Protection

The drainage system of Khlong Ae (Khlong Phai) is flowing into Khlong Yan. During the construction of water diversion weir, the tributary sections are of steep slope from weir to the power house downstream and further from the power house to Khlong Yan. Therefore both sections are good for drainage and the flood is flash flood.

3.3.9 Mineral Deposit

There are no potential mineral resources in the project area of economical scale. However, further 2.5 km southwards from project site is the sources of construction industry

- 37 - Macro Consultants Co., Ltd Final Report IEE of Khlong Ae Mini Hydropower Project EXECUTIVE SUMMARY granite rock, Tin and Tungsten. Moreover, further 3 km. westwards from project site is also the potential area of Tin and Tungsten.

3.4 Quality of Life Values

3.4.1 Socio-Economics

Most people are native people living in this area for generations. They are mostly Buddhism. The social status is agricultural type with relatives and neighbours closely helping hands. The main occupations are farming, employee and trading. The economic plants are Para Rubber and Palm Oil.

According to the interviews of 30 community leaders and organization representatives, they thought that the high fuel oil price is major problem that needed urgent to moderate solutions. This is because it influences the daily income/expense of people. Up to 96.67% of them have positive attitude toward renewable energy in electricity generation. The reasons are the reduction of environmental problem and can solve electricity frequent black out problem. The benefit from project should be the consistent electricity service, the community development fund, the reduction of forest intrusion. The negative attitude from Takuk Tai leader is that the project site locates at the watershed area of Vibhavadi Waterfall which is the important tourism place of the district and also the water supply resource of people as well as probable environment impacts.

The 364 households survey reveals 3.95 average member per house. The income and expense are nearly equal at average18,834 Baht/month and 18,658 Baht/month, respectively. Up to 30.22% of them though that the project will provide more positive benefit and negative impacts while 21.70 % though adversely and 15.38% though of equal pros and cons. Up to 39.84% of interviewed household still have no comment. Those who agree with the project is counted as 36.26% while 23.90% disagree. The reasons of disagreement are dealing with natural resources and environment impacts, especially to the Vibhavadi Waterfall.

3.4.2 Land and Property Compensation

The locations of all project components, weir, headrace, surge tank, penstock, power plant and access road are in the area of Khlong Yan Wildlife Sanctuary. There is no private land of people to be compensated. The power line from project will link with PEA line at Kiri Ratthanikhom District by constructing line along 18 km distance of the existing road without compensation.

3.4.3 Public Health and Nutrition

The existing data from the health centers in Vibhawadee and Khiri Ratthanikhom Districts indicated that the majority of populations residing in the project area have health problem related to respiratory diseases. The 150 sampled villagers in three Tumbon of that districts namely Takuk Nua (49.0%), Takuk Tai (33.1%), and Nam Hak (17.9%) were randomed for further physical examination consisting of 67.5% of female and 32.5% male participated in this health program. Villagers were age groups of 30-59 years (43.7%), below 15 years (35.8%), and others 20.5%. The physical exam also measured the body mass index (BMI) to explore obesity condition that showed the people having normal value BMI of

- 38 - Macro Consultants Co., Ltd Final Report IEE of Khlong Ae Mini Hydropower Project EXECUTIVE SUMMARY

45.6% and having high value BMI of 30.9 %. Others ailments found from the physical examination showing 1.3% had problems of skin, oral cavity, and conjunctivitis. Other findings were headache 17.2%, malaise and fatique 11.3%, gastritis 9.3%, mucous cough and sore throat 8.6%, arthritis 6.0%. People from Takuk Tai subdistrict had stool exam and found hookworm infection 15.8%, and E. coli protozoan infection 2.6%. Stool samples from Takuk Nua found hookworm 14.5%, strongiloides 1.6% and giardiasis 1.6%. From Nam Hak subdistrict, only hookworm infection 4.2% were found. Test of 150 blood samples with COPT method found all negative results for schistosomiasis.

The survey of medically important intermediate hosts of diseases such as snails, fish crabs, rats and mosquitoes had been conducted during 10-25 June 2007 in 9 stations covering Khlong Ae (or Khlong Pai), Klong Yan and its tributaries could be summarized as follows:

1) Fresh water snails : we found four medical important snails of Pila angelica in the Family Ampullariidae, Filopaludina (Siamopaludina) martensi martensi in the Family Viviparidae, Melanoides tuberculata, and Tarebia granifera in the Family Thiaridae. The survey had not found any Neotricula snails, intermediate host of schistosomiasis. The collected snails were grouped for examining of cercariae in the lab by the methods of light shedding and crushing. The findings showed two species of non-medical important cercariae of Xyphidio in the snail Melanoides tuberculata. 2) Fresh water fish : we found various kinds of white-scale species of Cyprenoid fish such as Common silver barb (Puntius gonionotus) Spanner barb (Systomus lateritriga), Siamese river abramine(Paralaubuca riverori), Soro brook carp (Neolissocheilus soroides), Beardless barb (Cyclocheilichthys apogon), and Rasbora daniconius labios. Findings from the lab did not show appearance of larval stage (metacercaria) of important human liver fluke (Opithorchis viverrini), but only the young stage parasite of intestinal fluke in many survey stations, which is not causing severe pathogenic condition to health. 3) Crabs : Finding of crabs in the natural was scarce. We collected water-fall crabs and rock crabs in the site. Results from the lab for examining important parasites found all negative. 4) Rats : We collected many species of rats namely, Bandicota salvilei, Bandicota indica, Rattus rattus, Rattus rajah, Rattus surifer, and Rattus muelleri). All the rats indicated no evidence of human parasitic transmission, and non were carriers of leptospirosis. 5) Mosquitoes : Many species of medical important vectors were found in all survey stations such as Anopheles the vectors of malaria, Aedes the vector of dengue fever and chikungunya, Culex the vector of Japanese encephalitis, and Mansonia the vector of filariasis.

3.4.4 Historic and Archeological Site

There are no important archelogical sites within the project area. However, 2 nearby sites are near the project in Kiri Ratthanikhom District which are Tam Singkorn and Tam Buangbaeb and Perngpha Cave.

3.4.5 Tourist Attraction and Recreation

The major tourism site within project area is Vibphavadi Waterfall (Khlong Phai Waterfall) which have 9 steps of falls in the fertile forest of Khlong Yan Wildlife Sanctuary. The visitor record in 2008 was highest in April up to 11,158 visitors.

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4. ENVIRONMENTAL IMPACT ASSESSMENT

4.1 Physical Resources

4.1.1 Topography

Construction Phase

The reinforced concrete weir with the height and length of 7.00 m. and 35.00 m. respectively will be constructed on Khlong Ae (Khlong Phai). There will be temporally water diversion at construction site on Khlong Ae during construction of weir. The asphaltic road of 4.00 m. width will be constructed from weir and is laying out along headrace on top of hill area to the downstream power house with total length of 1,635 m. road in the Khlong Yan Wildlife Sanctuary area. Water will be stored along tributary channel upstream in front of the weir with maximum water level at the top of channel bank. There will be impact from the mentioned construction work. But this construction is only little effected to the topography of the area and is limited in the specific area. Therefore this development does not cause serious damage to the topography of the area.

Operation Phase

After completion of construction work, there will be no increase in changing of topographic area at all.

4.1.2 Climatology and Meteorology

Construction Phase

The construction activities of project will have no significant impact on the evaporation, relative humidity and rainfall intensity in both local and regional level.

Operation Phase

The water storage upstream of the weir will induce higher relative humidity and evaporation from Khlong Ae. However, it will not change the local climatic status to a significant level.

4.1.3 Air Quality

Construction Phase

The construction activities will create dust particulates from the open cutting and soil excavation works. Apart from that, the working machine will also release fugitive dust and smoke, especially at the power plant site near the Tapee Watershed Management Unit and the Khlong Yan Wildlife Sanctuary. Luckily, the area is surrounded by forest that can protect and absorb the suspended particles before reaching nearby communities. The dust impact during transportion of construction materials / components is expected to be low as the main roads surface condition is asphaltic.

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Operation Phase

The operation of project power plant is similar to other hydropower plants. No fuel is needed. So, the air quality will not be changed.

4.1.4 Hydrology of Surface Runoff

Construction Phase

Surface runoff may be effected by construction activities namely: sediment deposited from soil erosion in the flowing channel and construction of weir on the tributary channel. But it is planned to construct the cofferdam only half of flow channel width. Water can still flow to downstream by the other half. When the construction of weir on the first half is completed and starting to construct the second half, water can flow over the half length of weir. Therefore the impact is expected to be at low level.

Operation Phase

At weir site, flow area is reduced and backwater is taking place in front of weir to upstream direction following by reduction of flow velocity upstream of the weir. If there is enough water, water still can flow over weir all year. As there will be some bypassed water for hydropower generation, the flow along tributary channel from weir to power house will be reduced. Exception is made only during the stop of hydropower generation during the day time of tourist season. Downstream of power house, with and without project, flow along tributary channel still be the same discharge.

4.1.5 Surface Water Quality

Construction Phase

The forest clearance and open cutting tasks at the dam site can cause soil erosion. Soil sediments and traces of construction materials (rock, sand, soil, lubricants) can be flushed to reach the surface water resources which causes higher Turbidity, and deteriorates the water quality. However, the impact is temporary short term. After finishing the construction, the water quality should be back to normal condition.

Operation Phase

The stagnant water upstream of the weir will have less oxygen absorbing efficiency than natural flowing water. The Dissolved Oxygen (DO) will be reduced, as well as the assimilative capacity. On the contrary, the released water from the power plant can absorb more O2 from mixing air and the content downstream will be increased.

4.1.6 Groundwater

Construction Phase

The weir and power plant construction of this project is of small scale. No activities will contaminate the ground water quality. So there will be no impact to both quanity and quality of ground water.

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Operation Phase

The project storage area is in a high slope land of Khlong Yan Wildlife Sanctuary. The ground level of weir creast is 189 m higher than the power plant without any linkage to ground water aquifer. So, there will be no impact to both quantity and quality of ground water.

4.1.7 Geology and Seismology

Construction Phase

The small scale construction of project will create no impact to the geology change and seismic potential in the project area and vicinity.

Operation Phase

There will be no direct and indirect impact to geology pattern of the project area and its vicinity as the small scale of weir with 7 m heigh and 35 m length. The design of one story power plant can bear the seismic and will create no serious impact to the engineering structures of project.

4.1.8 Soil Resources

Construction Phase

During the construction period, oil split from heavy machine will affect the soil chemical properties at that area. However, the suitable management in the construction area will lead to less oil split affect. The soil erosion perhaps severe occurred. This is due mainly to clearing of cover plant and explosion of surface terrain leading to higher rainfall detachment.

Operation Phase

The propose weir has less affect on soil moisture both upstream and downstream areas. The upstream soil is composed of shallow soil, rock land and slope complex unit. While, downstream soil has naturally water supply by local waterway

4.1.9 Erosion and Sedimentation

Construction Phase

Clearing the forest area for soil surface excavation and transportation of construction materials namely: at access road to the project, headrace weir and appurtenance structures, surge tank, penstock and power house especially the construction site near the edge of river bank will result in increasing the erosion specifically in the west season. But the mentioned impact is not serious.

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Operation Phase

Along the tributary channel from downstream of weir to power house, erosion of tributary banks may result from rapid increasing and drawdown of water level. This impact is expected to be at low level because the bypass flow for hydropower generation is small when it is compared with flow during the wet season. And there will be stop of hydropower generation during the day time in tourist season in order to increase the flow over water fall. For tributary downstream of power house portion, at the beginning, there will be small erosion and it will become equilibrium between erosion and sedimentation in a short period of time.

4.1.10 Noise and Vibration

Construction Phase

The noise from construction vehicles machine and transportation activities will cause low impact as the surrounding area of weir is only highland forest. The construction activities around the power plant site will affect the Tapee Watershed Management Unit that locates only 50 meter further. The noise level calculation indicates that noise reaching the unit will be a bit higher than standard level. So, mitigation measures must be planned by scheduling the construction works to be during weekend days to avoid the working hours of the government office.

The Vibration will be caused by 2 activities (1) The construction materials vehicles (2) the foundation construction during piling of the power houses. However, it is expected to be of low impact as the scale of construction is small.

Operation Phase

There will be no noise and vibration impacts from the operation of project to the level of annoyance.

4.2 Biological Resources

4.2.1 Aquatic Ecology

Construction Phase

The construction activities may cause soil erosion into water resource resulting in higher turbidity, especially in rainy season. The higher turbidity cause direct impact to the Primary Productivity Process of water resources that affect the slow movement organisms such as plankton, benthic animals, etc. The construction at weir site needs to excavate the bottom of Khlong Ae and can destroy the bottom aquatic organisms and aquatic weeds. However, due to the lower abundance of aquatic organism, the impact will be just temporary.

Operation Phase

The aqutic organism upstream of the weir will be more abundance during operation. The electricity generation process will also enhance the aquatic living productity upstream.

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4.2.2 Forestry Resource

Construction Phase

During construction the forest area of 29.75 Rai in Khlong Yan Wildlife Sanctuary area will be cleared which cost around 582,454 Baht. The construction workers can also illegally cut tree and collect forest stuffs.

Operation Phase

The loss of forest at project construction sites will be permanent. During operation phase, there will be no more forest loss expected.

4.2.3 Wildlife Resource

Construction Phase

The construction area in Khlong Yan Wildlife Sanctuary which is a tropical rain forest will reduce the wildlife habitat and food source of 29.75 Rai or 0.01% of the sanctuary area. The impact is assessed to be of low level as the animals can move to nearby area of the same ecology. The construction workers may illegally catch wildlife for food during construction period.

Operation Phase

Various kinds of animal can return to the project area and used as habitat and food sources such as rodents and birds. During dry season when the water in the stream is so low that animals can reach some area. The weir can restore water upstream and become alternative water sources for wildlife, mammals, reptiles. Amphibian can easier reach the area for water, food, and breeding. However, the area downstream of the weir to the power plant will get small negative impact, especially less water during night time due to the diversion of water through headrace and penstock to generate electricity. The impact is of low level as most night time animals are those small wildlifes that consume just small quantity of water. It is expected that these wildlives and amphibian can adapt themselves to the changing environment.

4.2.4 Watershed Quality Area

Construction Phase

The construction work of project will be in the watershed classification zone 2, 3 and 4. According to the land use measures in watershed class 2 of the cabinet approval on “The Southern Basin Watershed Classification” on November 7, 1989, there is no restriction related to the construction of project component in watershed area class 2. The land use for mining, forest concession, and other businesses are allowed in watered area class 3 and 4. So, the construction of project is conformed with the cabinet approval.

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Operation Phase

The project components will already constructed in watershed class 2, 3 and 4 zone. No more further land use in zone 1 of the watershed are in operation phase.

4.3 Human Use Values

4.3.1 Land Use

Construction Phase

The approximately 29.75 rai of natural forest in Khlong Yan Wildlife Sanctuary area will be turned to construction and development area . The changed area will composed of access road (5.11 rai), weir and accessory building (6.58 rai), supported road and headrace (14.81 rai), surge tank (0.14 rai), penstock (0.82 rai) and power house and accessory building (2.29 rai).

The electrical line route from Khlong Ae Power House will connect to local electrical line of PEA-Khiri Ratthanikhom District Branch. The construction of 18 kilometers electrical line will have less affect on land use change as it can be constructed in the commom right-of- way as the existing transmission line along the royal highway side.

Operation Phase

Only the land use in the construction and development areas will permanently change from forest to be construction and development areas during construction period. Whilst, the operation of Khlong Ae Mini Hydropower Project has less influence on land use change.

4.3.2 Transportation

Construction Phase

It is assessed that the Rural Highway No.3176, Ban Yang – Takuk Nua Road and Provincial Highway No.4247 will be affected from the transportation activity of workers and construction materials. The existing V/C ratio of these roads are in the range 0.03-0.13 which indicates very fluent traffic. The transportation of project will not change this range of V/C ratio. So, the impact to traffic will be less. However, the heavy equipment loads can destroy the road surface resulting in dust and noise problems, as well as road accidents.

Operation Phase

There will be no impact from transportation during project operation.

4.3.3 Power Supply

Construction Phase

Electricity will be used temporary in a short time during construction. The contractor will co-ordinate with the Provincial Electricy Authority, Branch Ban Ta Khun District for the

- 45 - Macro Consultants Co., Ltd Final Report IEE of Khlong Ae Mini Hydropower Project EXECUTIVE SUMMARY expense of transformers and temporary jumping lines for construction machine and light. The requirement impact is low as the use of electricity for construction is not much.

Operation Phase

The electricity generation from Khlong Ae project is a clean renewable energy with less impact to the environment. The rated capacity of 1,810 Kw can generate 8.11 million unit annually that can support the high voltage transmission line of PEA at Khiri Ratthanikhom District. According to the data from socio-economic interview, PEA service in the project area is facing frequent electricity shut down with irregular power. The operation of Khlong Ae project will strengthen the service system for the project area and vicinity. It can solve the existing problem which is a positive impact of smooth service and prolong the lifetime of electrical appliances.

4.3.4 Water Use

Construction Phase

The source of construction water will come from Khlong Ae that can provide all year round. The water use for consumption of workers is generally not much. They use bottle water for drinking and cooking. So, the impact of water shortage at the downstream community is low. However, the construction will increase the turbidity of water that can disturb the village pipe water supply of Moo 8. Ban Wang Phakwaen in Takuk Tai district that uses raw water from Khong Ae downstream of the weir site. In addition, the tourists will be impacted from turbid waterfall too. The contractor should inform the downstream community in advance so as to prepare for mitigation measures.

Operation Phase

The quantity of water in Khlong Ae downstream of the weir to the power plant will be less than existing condition as some portion of water will be diverted through headrace, surge tank and penstock to the power plant. The direct impact is the less raw water at the Vibhavadi waterfall to supply the village pipe water system of Ban Wang Phakwaen. To mitigate this problem, the project must renovate the existing raw water intake and construct a new water intake upstream of the weir with receiving pipe connecting both intakes.

The water use for agriculture is expected to have no impact as the water passing generator will be relased back into Khlong Ae to maintain the downstream quantity as usual.

4.3.5 Agriculture and Livestocks

Construction Phase

The construction and development areas of Khlong Ae Mini Hydropower Project located in conservation zone of Khlong Yan Wildlife Sanctuary areas. In addition, both the upstream and downstream areas of proposed weir are forest area. So the development project has no affect on agriculture and livestocks. Similary, the electrical line route from Khlong Ae Power House to connect with local electrical line of Khiri Ratthanikhom Districtl Electricity Authority also has less affect on agriculture land use.

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Operation Phase

The operation of project has no affect on agriculture and livestock. This is due mainly to water supply of the areas and vicinity is still naturally operated.

4.3.6 Fishery and Aquaculture

Construction Phase

It is found that there are no permanent fishing equipment nor aquaculture cages in Khlong Ae or even onshore aquaculture. So, there will be no impact on fishing and aquaculture. Although some family along the bank catches fish for household consumption, it is not for commercial career. The impact will be low.

Operation Phase

There will be storage water upstream of the weir. The condition of flow will change from flowing water to stagnant or semi-stagnant water with water all year round. Such condition is good for aquatic organisms in terms of habitat and breeding ground. There will be no effect to the fishery and aquaculture as the location of weir and storage area is in the Khlong Yan Wildlife Suncturay that prohibit these activities.

4.3.7 Irrigation

Construction Phase

Construction of weir and appurtenant structures are made each time only half of tributary channel width by construction of cofferdam around the construction site. Water still can flow on the other half of the channel from upstream to downstream direction. Therefore there will be no effect to the discharge on Khlong Ae (Khlong Phai) for irrigation or other agricultural water uses of both Takuk Tai Subdistrict, Vibhavadi District and Takuk Nua Subdistrict Khiri Ratthanikhom District.

Operation Phase

Weir and hydropower plant of the project are located in Khlong Yan Wildlife Sanctuary. Irrigation of agricultural areas are in downstream of hydropower plant. Hydropower generation of the project is carried on by diverting water in front of weir through pipe system and finally to power house. Then water is drained into Khlong Ae through tailrace. Therefore, there will be no effect to the various kind of water uses along Khlong Ae downstream at all.

4.3.8 Drainage and Flood Protection

Construction Phase

Construction of weir and appurtenant structures on the tributary channel may effect the flow area. But the weir construction is made by construction of cofferdam only half of the tributary channel cross section. And allow the water flows through the other half of channel

- 47 - Macro Consultants Co., Ltd Final Report IEE of Khlong Ae Mini Hydropower Project EXECUTIVE SUMMARY cross section. After construction completion, cofferdam is constructed on the other half of river channel and the water can flow over weir of half width. Therefore the effect to the drainage during the construction of weir and appurtenant structures will be at low level. While the construction of the other project features will be no effect to the drainage and flood projection at all.

Operation Phase

The construction of weir of 7.00 m. height on Khlong Ae (Khlong Phai) will create backwater effect to the upstream direction which will result in low flow velocity in backwater region. This is the positive effect during high flow in the wet season. The slope of Khlong Ae (Khlong Phai) from weir site to downstream of power house is steep. And from downstream of power house to Khlong Yan is less steep than the upper part, but it still be rather steep. The tributary channel line of this portion is rather straight which will be good for drainage system. Therefore, it can be concluded that the carrying of this project will effect to drainage and flood protection at low level.

4.3.9 Mineral Resources

Construction Phase

There are no mineral resources or economical potential mineral area in the project area. So, the construction of project will have no impact on mineral resources.

Operation Phase

The will be no direct and indirect impacts to the mineral resources from the operation of project.

4.4 Quality of Life Values

4.4.1 Socio-economics

Construction Phase

The project construction will create more job opportunity to the local people, especially employee career. There may be some non-local employee that can cause social problems of robbery, quarrel, attack among workers and nearby communities.

Operation Phase

The operation of project will provide more stable electricity service to the local people. The problem of flack out will be reduced and can maintain the lifetime of electrical appliances.

Appart from that, the local authorities can publicize and arrage tourism promotion activities such as “Musium Knowledge of Vibhavadi Waterfall” to enhance tourism and earn more local income.

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4.4.2 Land and Property Compensation

Construction Phase

As the location of all project components are in the Khlong Yan Wildlife Sunctuary area, there are no construction in private land that needed to be compensated. The construction of 18 km. transmission line from the power plant to link with PEA system in Khiri Ratthanikhom District can follow the existing line route of PEA along the road right of way with no need for compensation

Operation Phase

There will be no more private land needed. So, no impact on compensation.

4.4.3 Public Health and Nutrition

Construction Phase

In the construction phase, there will have groups of workers and labor forces move into the dam site and settle down through the period of the dam building. In case if there are evidences of unhygienic cooking and toiletry behaviors, they will spread water-borne diseases.

Operation Phase

After completion of the dam construction, there will have collection of water in the reservoir in front of the dam crest where the vectors and intermediate hosts of water-borne diseases can multiply their populations such as mosquitoes, fish, snails, and rats.

4.4.4 Historic and Archeological Site

Construction Phase

There are no archeological sites within the project area. So, no impact occurs to archeological values.

Operation Phase

No, impact too.

4.4.5 Tourist Attraction and Recreation

Construction Phase

As the construction site locates upstream of the 9 steps of Vibhavadi Waterfall, it can increase the turbidity of water as well as contaminate from fuel oil, lubricant of construction machines. It will cause negative impacts to visitors and tourists.

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Operation Phase

The diversion of water bypassing Vibhavadi Waterfall to generate electricity will highly affect the tourism value in terms of dry waterfall for some days of dry season. It conforms with the local people concern that afraid of the loss in waterfall tourists.

It can be alleviated by stopping generation during peak tourist hours at the waterfall. This nitigation measure can reduce the tourism impact to the acceptable level. It is a compromising means to maintain the waterfall so as the tourism activities can be continued and the project can be sustainable.

Apart from this, the local agencies can publicize and arrange tourism promotion activities such as the construction of “Education Musium” of Vibhavadi Waterfall locating in public area near the waterfall entrance. The museum can be the center of education by providing media such as VDO presentation, meeting room, exhibition room of Vibhavadi Waterfall and the Hydropower plant, etc.

4.5 Conclusion of Environmental Impact Assessment

4.5.1 Summary of direction of anticipated impacts and severity degrees on the related Environmental Resources/Values

Table 4.5-1 presents the direction of anticipated impacts and severity degrees on the related ER/V both in the construction and operation phases of the project development.

4.5.2 Priority Arrangement of Environmental Resources/Values

The purpose of priority setting of the environmental resources and values in the study area for the project development is to specify and prioritize the concerned ER/V required protective and mitigate measures as well as the environmental quality monitoring program from the project implementation. The priority setting process is derived from findings of previous study reports of Khlong Ae Mini Hydropower project; collection of revised and updated project development plan; integration of current study results of existing ER/V and the anticipated environmental impact evaluation on the ER/V of interest.

The consequences of anticipated impact evaluation are normally assessed in term of impact direction (positive and negative impacts) and impact severity divided into 5 levels i.e. relatively high, moderate, relatively low, very low and no impact . Therefore the priority of ER/V is arranged in accordance with the impact severity levels, i.e. the first, second and third priorities corresponds to moderate - relatively high, very low - relatively low and no impact respectively.

1) First Priority. The ER/V of this category is expected to experience either positive or negative impact of moderate - relatively high level. Particular attention and appropriate protective/mitigate measures must be paid and planned for the this level adverse impacts.

2) Second Priority. This ER/V category is normally exposed to very low - relatively low level impacts from the project development but still requires careful attention and appropriate mitigate measures particularly the probable negative effects.

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3) Third Priority The last category of ER/V is expected to be affected at no impact level from project development

Table 4.5-2 summarizes the arrangement of priority for the ER/V.

Table 4.5-1 Summary of Impact Assessment for Khlong Ae Mini Hydropower Project

Environmental Resources/Values Level of Impact Construction Operation 1. Physical Resources 1.1 Topography - 1 0 1.2 Climatology and Meteorology 0 0 1.3 Air Quality - 2 0 1.4 Surface Water Hydrology - 1 - 2 1.5 Surface Water Quality - 3 - 1 1.6 Groundwater 0 0 1.7 Geology and Seismology 0 0 1.8 Soil Resource - 1 + 1 1.9 Erosion and Sedimentation - 2 - 1 1.10 Noise and Vibration - 3 0 2. Biological Resources 2.1 Aquatic Ecology - 3 + 1 2.2 Forest Resource - 3 0 2.3 Wildlife Resource - 1 + 1 2.4 Watershed Quality Area - 1 0 3. Human Use Values 3.1 Land Use - 1 0 3.2 Transportation - 1 0 3.3 Power Supply - 1 + 4 3.4 Water Use - 3 0 3.5 Agriculture and Livestock 0 0 3.6 Fishery and Aquaculture 0 0 3.7 Irrigation 0 0 3.8 Drainage ang Flood Protection 0 - 1 3.9 Mineral Deposit 0 0 4. Quality of Life Values 4.1 Socioeconomics + 1 + 4 4.2 Land and Property Compensation 0 0 4.3 Public Health and Nutrition - 1 - 1 4.4 Historic and Archeological Site 0 0 4.5 Tourist Attraction and Recreation - 3 - 1

Remarks : + = Beneficial impact - = Adverse impact 0 = No impact 1 = Very low impact 2 = Relatively low impact 3 = Moderate impact 4 = Relatively high impact 5 = Very high impact

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Table 4.5-2 Priority Arrangement of Environmental Resources/Values for Khlong Ae Mini Hydropower Project

Environmental Resources/Values Priority Rank First Second Third 1. Physical Resources 1.1 Topography X 1.2 Climatology and Meteorology X 1.3 Air Quality X 1.4 Surface Water Hydrology X 1.5 Surface Water Quality X 1.6 Groundwater X 1.7 Geology and Seismology X 1.8 Soil Resource X 1.9 Erosion and Sedimentation X 1.10 Noise and Vibration X 2. Biological Resources 2.1 Aquatic Ecology X 2.2 Forest Resource X 2.3 Wildlife Resource X 2.4 Watershed Quality Area X 3. Human Use Values 3.1 Land Use X 3.2 Transportation X 3.3 Power Supply X 3.4 Water Use X 3.5 Agriculture and Livestock X 3.6 Fishery and Aquaculture X 3.7 Irrigation X 3.8 Drainage ang Flood Protection X 3.9 Mineral Deposit X 4. Quality of Life Values 4.1 Socioeconomics X 4.2 Land and Property Compensation X 4.3 Public Health and Nutrition X 4.4 Historic and Archeological Site X 4.5 Tourist Attraction and Recreation X

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5. PROPOSED MITIGATIVE MEASURES AND MONITORING PROGRAM

The following protective and mitigate measures and environmental quality monitoring program were proposed in accordance with the results of anticipated impact assessment during both the construction and operation periods. The proposed and applicable mitigation measures and monitoring program would be eventually integrated as part of the project development plan so as to minimize any adverse effects and to follow up in a long-term basis on any affected environmental quality as well as the project implementation efficiency.

5.1 Protective and Mitigate Measures

5.1.1 Physical Resources

The mitigation measures for impacts that may occur from the project can be summarized as follow:

(1) Pre-construction Phase

Publicize the project information to all stakeholders to let public know the progress of project, the features and the construction schedule, etc.

(2) Construction Phase

1) The project must provide construction supervising company to closely monitor the activities of contractor throughout the construction period according to the schedule and the environmental mitigation measures.

2) The soil excavation and backfill land adjustment must be done in the limited area as planned and must have measures to protect soil / rock erosion not to reach the water resource. Avoid activities that cause higher turbidity or suspension into the water, especially during major tourism periods.

3) The forest cutting-soil open cutting activities must be done part by part according to the construction orders and not over excavation interms of area and timing. If possible the trees along the banks of water resources should be kept for the last cutting.

4) The foundation construction and loud noise activities should be scheduled to tbe done during weeken (Saturday – Sunday) to avoid / Reduce noise impact to the officers of Tapee Watershed Management Unit. The activities that cause vibration should be avoid the night time period or resting time of people.

5) Once the project is approved, the project must coordinate with the DNP to measure the exact boundary of forest that needs to be cut and mark on every tree. The cutting must be carefully done within the boundary and shoud coordinate with the Chief of Khlong Yan Wildlife Sanctuary to monitor the moving of trees without extruding other outside area.

6) Take a detail survey before cutting trees and grading the forest area, by this mean, the slow movement wildlife can be saved as well as those animals living in rabbit- holes, etc. To move animals, it is recommended to corrdinate with the Khlong Yan Wildlife

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Sanctuary to take care of those leftover animals in the project area which are mostly those hiding or living on trees.

7) The construction contractor must provide warning sign or project schedule PR board to inform people and tourists of the waterfall about the project.

(3) Operation Phase

1) In the dry season or tourist season starting from new year to the end of April (30 December to 30 April) the operation during the day time for power generation should be stopped for about 11 hours (from 7:00-18:00). But in the less flow month the day time operation should be stopped for about 6 hours (from 9:00-15:00 or other appropriate period depending on the time the tourists visiting Vibhavadee waterfall). At the time of no operation the river flow should be drained directly to downstream area.

2) Sediment deposits should be dredged once every 2-3 years and discarded at appropriate area. Dredging of soil sediment or sand sediment in the upstream of weir should be carefully performed to avoid dispersion.

3) Small opening screen should be installed at the head tank inflow to prevent small aquatic life entering the conduit.

4) Improve and construct 2 water intakes of raw water pipeline for village water supply production for Moo 8 Ban Wang Phakwan Tambon Takuk Tai, one at the existing location and the other at upstream area of the weir with connecting pipe to the main pipeline.

5.2 Environmental Quality Monitoring Program

1) Water quality monitoring at 5 locations as shown in Figure 5.2-1 to investigate water quality changes during construction and operation phases as follows : - During construction phase, water sampling and analysis should be made once every 4 months (3 times a year) and during operation phase 2 times a year covering wet and dry seasons for the first 5 years. - The monitoring expense during construction phase should be included in the construction cost. But during operation phase it should be under the responsibility of the implementation organization with the expense of 0.10 million baht/time or 0.20 million baht per year.

2) Aquatic ecology monitoring at 5 locations the same as water quality and should be conducted at the same time as water quality. - During construction phase, sampling and analysis once every 4 months (3 times a year) and during operation phase 2 times a year for the first 5 years. - Monitoring expense during construction phase should be included in the construction cost. But during operation phase it is responsible by the implementation agency with the expense of 0.05 million baht/time or 0.10 million baht per year.

3) Sediment deposit dredging in front of weir (upstream) - Dredging once every 2-3 years to maintain storage capacity upstream of weir.

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Power House

Khlong Ae Surge Tank

(Khlong Phai) Takuk Tai Subdistrict SW 1 SW 2

SW 4 SW 5 Khlong Ae SW 3 (Khlong Phai)

Weir

Num Hak Subdistrict

Scale 0.0 1.0 2.0 3.0 4.0 Km.

Legend :

Weir Headrace

Surge Tank Penstock Khlong Yan Wildlife Sanctuary

Power House Transmission Line

Access Road Water Sampling Point

Figure 5.2-1 Sampling Locations of Surface Water Quality and Aquatic Ecology Monitoring in Khlong Ae

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- Expense about 2 million baht per time and should be responsible by the implementation egency.

4) Attitude survey of local residents withing 10 km.radius from the project site. - Carry out 3 times in the 1st, 3rd and 5th year operations. - Expense about 0.40 million baht per time responsible by the implementation agency.

5) It is neccessary to conduct surveillance of the medically important snails that are potentially transmitting parasitic diseases between men in along the canal of Klong Aae (Klong Pai). This survey proposes five stations for the disease investigation in the same site of surface water quality examination. - The survey performs twice a year in the summer and in the rainy season, start in the first year for three consecutive years. - The cost of investigation and surveillance needs the budget of 0.5 M Baht/ year under the responsibility of the Project’s initiative.

6. ENVIRONMENTAL ECONOMICS STUDY

The environmental economic study is carried out by converting the environmental impacts assessed by environmental experts into monetary terms in order to reflect the potential impacts cannot convert into monetary terms. The environmental economists try to find appropriate methodology as well as conditions specified in the concept of environmental economic assessment.

From the results of environmental impacts assessment, some impacts have direct mitigation measures. Some may need the expense and some may not need to alleviate problems. However the impacts from project construction which have not yet been mitigated may have consequent effects to the operation phase. If it is assessed and converted into monetary term it can serve as the indicator of the tangible effect of the project.

Criteria for screening the impacts that should be assessed of their economic values would follow TDRI quidelines as follows :

• Environmental impacts at low levels will not be assessed of their economic values. • Environmental impacts at high and moderate levels will be considered into 2 cases : Case 1 : with mitigation measures by allocating expense for monitoring to reduce the impacts to low level. This will not be assessed of its economic value. Case 2 : without measures like Case 1 or with measures like Case 1 but the impacts still exist. This will be assessed of their economic values.

The results of impact screening for their economic value assessment revealed that biological resources of forestry and wildlife have the highest impacts. This is because the trees in the construction area have to be cleared out before construction start. It will be permanent loss of about 29.75 rai forest area. To assess the value of forest loss it is made by

- 56 - Macro Consultants Co., Ltd Final Report IEE of Khlong Ae Mini Hydropower Project EXECUTIVE SUMMARY using the Direct/Surrogate Market Approach following the Replacement-Cost Technique. The results of forest value loss assessment accounts for about 582,454 baht.

The assessment of Total Economic Values (TEV) can be made by combining all environmental impacts to be incurred in the future then converted into Present Value with the discounted rate of 10%. For the forest loss which has been estimated above at 582,454 baht with the timber growth rate of 2.50% per annum it is evaluated that the TEV would be equal to 730,322 baht.

It is concluded that the micro-hydropower project of Khlong Ae has not much impact on environments and most of the impacts have mitigation measures to alleviate the impacts to the minimum level. However, as for the forest resource the project implementation has to cut down the forest area of about 29.75 rai which is not much forest loss. This impact has been evaluated of its value for 50 year project life (after construction completion) having the TEV of 730,322 baht which is not so high value. From this evaluation the Project should be received consideration to go ahead for implementation.

7. PUBLIC PARTICIPATION AND PULBIC RELATIONS

7.1 Objectives

1) Organize the Project’s public relations to provide information to and educate stakeholders to ensure truthful understanding and good attitude toward the Project.

2) Produce media for the publicity program to communicate Project-related information to target audience.

3) Organize public hearing sessions to gather the target group’s opinions toward the Project in which the participants came from local communities, NGOs, local organizations and governmental organizations located in the Project vicinity in the form of public forum open for questions, comments, opinions and suggestions. The information gathered from the said meeting would then be processed and incorporated in planning and implementation of the Project in order to increase its efficiency and effectiveness. In turn, local communities and stakeholders would develop better knowledge, which is adequate, clear, correct and thorough, so that they become more willing to cooperate in the development projects in the long run.

7.2 Scope and methodology

(1) Target group

People participation and public relations under this Project focused on communities and/or local people who live within 0-3 kilometers and 3-10 kilometers from the Project’s power house, which covered the area of Num Hak Subdistrict in Khiri Ratthanikhom District, Takuk Tai Subdistrict and Takuk Nua Subdistrict in Vibhavadi District, as well as NGOs, local organizations and governmental organizations located in the same area. There were 3 communities consisting of 300 households living within 0-3 kilometers radius from the power house, and 20 communities of 2,100 households within 3-10 kilometers.

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(2) Publicity program

The expert team met with local communities and relevant organizations to introduce the Project to the public during 29 April – 2 May 2008. The participants included Khiri Ratthanikhom District-Chief Officer, Senior Assistant District Officer of Vibhavadi District, Head of Khlong Yan Wildlife Sanctuary, Head of Tapee Watershed Management Unit, President of Takuk Tai Subdistrict Administrative Organization, President of Takuk Nua Subdistrict Administrative Organization and President of Num Hak Subdistrict Administrative Organization.

Public relations and publicity programs executed were aimed to periodically communicate Project’s detailed information to the target group in Num Hak Subdistrict in Khiri Ratthanikhom District, Takuk Tai Subdistrict and Takuk Nua Subdistrict in Vibhavadi District through such tools and media as pamphlet/booklet/papers featuring the Project public relations messages, meeting documents, mobile bulletin board and public relations via wired broadcast of Takuk Tai Subdistrict Administration.

(3) People participation

The expert team organized meetings to communicate the Project’s essential details as well as to discuss opinions, questions and answers among the local and relevant organizations. Five meetings and an observation visit to an existing mini hydropower project had been organized, the details as follows:

1) The first public hearing session (preliminary session), chaired by Vibhavadi District-Chief Officer with 22 participants, was organized on 28 May 2008 at Tapee Watershed Management Unit, Takuk Tai Subdistrict, Vibhavadi District, Surat Thani Province. 2) In the morning of 11 September 2008, the second public hearing meeting was chaired by the President of Takuk Nua Subdistrict Administrative Organization and took place at the assembly room of Takuk Nua Subdistrict Administrative Organization, Takuk Tai Subdistrict, Vibhavadi District, Surat Thani Province with 35 participants. 3) In the afternoon of 11 September 2008, the third public hearing meeting was chaired by the President of Takuk Tai Subdistrict Administrative Organization and took place at the assembly room of Takuk Tai Subdistrict Administrative Organization, Takuk Tai Subdistrict, Vibhavadi District, Surat Thani Province with 37 participants. 4) On 12 September 2008, the forth public hearing meeting was chaired by the President of Num Hak Subdistrict Administrative Organization and took place at the assembly room of Takuk Tai Subdistrict Administrative Organization, Num Hak Subdistrict, Khiri Ratthanikhom District, Surat Thani Province with 36 participants. 5) The last public hearing meeting (Post-training closing session), chaired by Vibhavadi District-Chief Officer, was organized on 15 January 2009 at the assembly room of Takuk Nua Subdistrict Administrative Organization, Takuk Tai Subdistrict, Vibhavadi District, Surat Thani Province with 64 participants from the target group including representatives from relevant organizations, local community leaders and general public who were interested.

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6) On 18 November 2008, representatives from target organizations and community leaders make an observation visit to Khlong Lumplok Mini Hydropower Project, Yan Takhao District, Trang Province. The 19 participants studied the operations of an existing mini hydropower plant and developed better understanding thereof based the matters of fact.

7.3 Outcome of public hearings

People participation and publicity program had drawn 213 participants and undertook its tasks through organized meeting sessions to shed light on the Project, response to questions arisen during the process, open forum for feedback and suggestions as well as the observation visit to an existing mini hydropower project.

It can be concluded that the majority of the participants agreed to and accepted the concept of Khlong Ae Mini Hydropower Project. They recognized the benefits of the utilization of fundamental resource in the area, i.e. water, to generate power to alleviate or eliminate the problems associated with power supply such as dropped voltage and frequent black-out due to unstable electric power. However, they voiced concerns over the probable impact in that the Project might cause water level in Vibhavadi Waterfall to fall and affect tourism attractiveness of the area.

8. CONCLUSIONS AND RECOMMENDATIONS

8.1 Summarizes the Beneficial and Adverse effects

The development of Khlong Ae Mini Hydropower project at the proposed site, would by no means create both beneficial and adverse effects to the surrounding environment which can be summarized as follows:

(1) Beneficial Effects

1) Make use of locally available resources for maximum benefit to local population, i.e. the suitable physical features and location of Khlong Ae (Khlong Phai) for a hydropower development.

2) It is hydro-power generation which is a clean renewable energy and has minimum environmental impacts.

3) Increase capacity and security for power distribution of the substation that feeding to Amphoes Khirivatnikom and Vibhavadee areas. The project will increase power production of 1.81 megawatts and energy of 8.11 million unit per annum to the existing system. It will help decrease the unstable problem of power supply in the project area.

4) With firm and stable power supply it will help prolong the use of household electrical appliances. In addition supplementary occupation which re….on electrical supply of the local residents can be made then improving their quality of life.

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5) with weir construction across a stream the storage water will exist and serve as alternative water source for wild animals both manmals and reptiles. It could be anew food source and reproduction ground.

6) Local agency can make use of the project to supplement and promote their tourist attractions in addition to the existing waterfall. Activity supporting the local tourism could be as building up a mesium for Vibhavadee Waterfall Study in the public area near the entrance to waterfall which can help increase the revenue from the visited tourists.

(2) Adverse Effects

1) Forest area in Khlong Yan Wildlife Sanctuary will be permanently loss about 29.75 rai which will reduce the area of the evergreen forest as habitat and food source for wild animals.

2) Headwork construction activity will create erosion and sedimentation and increase turbidity of the stream water. In addition, there is potential contamination of the stream water in the construction area from oil spile from heavy equipment operation. It could finally have effect on downstream water use especially those using the water as raw water source for water supply production as well as Vibhavadee waterfall tourists and aquatic ecology. These effects will be temporary and after the construction completion it is anticipated that water quality will be recovered.

3) Construction activity of electrical building will have effect on dispersion of dust and noise nuisance to the officers working at the nearby Tapi Watershed Management Office and Khlong Yan Wildlife Sanctuary Office.

4) In the operation period after the project construction is completed, the emerging ponding water in front of the weir structure would be the breeding grounds of various vectors like Anopheles, Culex, Mansonia. and other communicable disease carriers such as fishes, oysters, crabs, and rats

5) During power generation period water feeding to Vibhavadee waterfall will decrease which effect tourism. This effect has worry the local residents but according the operation plan for power production it will be no operation during tourist season on the day time in order to minimize the effect.

Based on the comparison of both beneficial and adverse effects for the project development, it can be concluded that the beneficial effects apparently outweigh the adverse ones. The anticipated negative impacts are generally at very low and moderate levels that are considered low in significance. Additionally, according to the projects mitigate measures provided, the impacts would be minimized to acceptable levels. Hence, it is believed the project is justified to proceed for development.

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8.2 Conclusions and Recommendations

All the project components are located in Khlong Yan Wildlife Sanctuary area including water storage area upstream of the weir, weir site, penstock, pressure release tank, water conduit, power plant building, and the access road. The project implementation at pre- construction phase Department of Alternative Energy Development and Efficiency (DEDE), the project owner, has to request and get approval from National Park, Wildlife and Plant Conservation Department (DNP) seed before implementation. However, in this Initial Environmental Exanimation (IEE) the Department of National Park, Wildlife and Plant seed does not allow the study team to access to the Khlong Yan Wildlife Sanctuary area for study and research by giving the reasons that the area is high mountain area, the origins of Khlong Yan and Khlong Kapor. The area is the fertile evergreen forest with high diversity of biology, scarce plants and wild animals are found in the area. Any development should not be allowed to carry out in this area to avoid the effects on forest and wildlife. Therefore, collection survey and sampling of the concerned environmental quality have been carried out in the nearby area outside Khlong Yan Wildlife Sanctuary.

From the results of environmental impact study to be incurred from the project development by comparing the beneficial and the adverse effects, it can be concluded that the project will have not much significant adverse effects and will be at low to moderate levels. It is anticipated that all the adverse effects will be at acceptable level when compared with the beneficial effects. The project has prepared mitigation measures together with monitoring programs for surveillance in order to check their efficiency and appropriateness. Therefore if the project has been approved for development in the proposed project area, it is suggested to maximize project benefit as follows :

1) Public participation meeting should be carried out atleast one time before project construction start at Moo 8, 11 and 12 of Tambon Takuk Tai and at Moo 6 and 2 Tambon Namhak.

2) Employment opportunity for project development should be initially open for the local residents as the project would impress the communities for their contributions and participation particularly help conserving the existing forest resources and wild animals in the surrounding area.

3) Project information dissemination and a publicity program should be conducted regularly so as to provide local residents better understanding and positive attitudes toward the project development.

4) Coordination with local agencies should be carried out in order that they can help release the project information and arrange activity supporting local tourism promotion, eg., building of museum for Vibhavadee Waterfall study in public area near the entrance of the waterfall. The revenue from the visited tourists will add up the income to local communities.

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