Kingdom of Bhutan Ministry of Economic Affairs (MOEA) Department of Hydropower & Power Systems (DHPS)

Project on

Power System Master Plan 2040 in Bhutan

Final Report Appendix

November 2019

Japan International Cooperation Agency (JICA)

Tokyo Electric Power Company Holdings, Inc. (TEPCO HD) TEPCO Power Grid, Inc. (TEPCO PG) Tokyo Electric Power Services Co., Ltd (TEPSCO) Nippon Koei Co., Ltd International Institute of Electric Power, Ltd. (IIEP) IL JR 19-075

Power System Master Plan 2040 Final Report Appendix

Table of Contents

Appendix-1 Results of Site Reconnaissance ...... 1-1 1.1 A-4: Kunzangling ...... 1-1 1.2 A-5: Tingma_Rev ...... 1-4 1.3 A-8: Dorokha ...... 1-9 1.4 W-6: Chuzom ...... 1-14 1.5 W-8: Zangkhepa ...... 1-19 1.6 W-19: Pipingchhu ...... 1-24 1.7 P-15: Tamigdamchu ...... 1-29 1.8 P-17: Tseykha ...... 1-32 1.9 P-26: Thasa ...... 1-39 1.10 P-28: Kago-1 ...... 1-44 1.11 P-29: Kago ...... 1-47 1.12 P-29R: Kago_Rev ...... 1-51 1.13 P-30: Pinsa ...... 1-56 1.14 P-34: Darachhu ...... 1-61 1.15 P-34R: Darachhu_Rev ...... 1-65 1.16 P-35: Dagachhu-II ...... 1-70 1.17 P-35R: Dagachhu-II_Rev ...... 1-76 1.18 P-38: Tashiding ...... 1-82 1.19 M-5: Bemji ...... 1-88 1.20 M-6: Jongthang ...... 1-92 1.21 M-6R: Jongthang_Rev3...... 1-97 1.22 M-11R: Wangdigang_Rev ...... 1-101 1.23 M-17: Buli ...... 1-106 1.24 M-18: Nyekhar ...... 1-110 1.25 C-7: Chamkharchhu-Ⅳ ...... 1-114 1.26 C-10: Chamkharchhu-II ...... 1-121 1.27 K-13: Minjey_Rev ...... 1-125 1.28 K-15: Phawan ...... 1-132 1.29 G-6: Khamdang_Rev ...... 1-138 1.30 G-7: Gongri_Rev ...... 1-144 1.31 G-9: Gamrichhu-3 ...... 1-151 1.32 G-10: Gamrichhu-2_Rev2 ...... 1-153 1.33 G-11: Gamrichhu-1_Rev2 ...... 1-159 1.34 G-13: Sherichhu ...... 1-165 1.35 G-14R: Uzorong_Rev ...... 1-169 1.36 G-16: Jerichhu ...... 1-174 1.37 G-19: Nagor ...... 1-177 1.38 G-22: Panbang ...... 1-181 1.39 N-1: Nyera Amari Kangpara (G) ...... 1-187 1.40 N-2: Lamai Gonpa ...... 1-190 1.41 N-3: Peydung-Kangpar_Rev ...... 1-194 1.42 N-3R: Paydung-Kangpar_Rev2 ...... 1-199

Appendix-2 MCA Score Table ...... 2-1 2.1 1st MCA Score Table ...... 2-1 2.2 2nd MCA Score Table ...... 2-19

Appendix-3 Environmental and Social Considerations ...... 3-1

i Power System Master Plan 2040 Final Report Appendix

3.1 National Environmental Standards ...... 3-1 3.2 Endangered Species ...... 3-2

Appendix-4 Power System Analysis ...... 4-1 4.1 Power Flow Analysis Results ...... 4-1 4.2 Power System Map ...... 4-11 4.3 Single Line Diagram...... 4-16

Appendix-5 Conceptual CAD drawings for the promising hydropower projects ...... 5-1 5.1 Dorokha (A-8) ...... 5-1 5.2 Pinsa (P-30) ...... 5-6 5.3 Chamkharchhu-II (C-10) ...... 5-11

Appendix-6 Findings on and Evaluation of Potential PSPP Sites ...... 6-1 6.1 Content of Investigation ...... 6-1 6.2 Criteria for Identifying PSPP Candidate Sites ...... 6-1 6.3 Map Study Results ...... 6-2 6.4 Site Survey Results ...... 6-2

Appendix-7 Number tables for Financial analysis ...... 7-1

Appendix-8 Figures ...... 8-1

ii Power System Master Plan 2040 Final Report Appendix

List of Figures

Figure A 1-1 Plot Plan (A-4) ...... 1-3 Figure A 1-2 Google Earth Image (A-4) ...... 1-3 Figure A 1-3 Plot Plan (A-5_Rev) ...... 1-8 Figure A 1-4 Longitudinal Profile (A-5_Rev) ...... 1-8 Figure A 1-5 Plot Plan (A-8) ...... 1-13 Figure A 1-6 Longitudinal Profile (A-8) ...... 1-13 Figure A 1-7 Plot Plan (W-6) ...... 1-18 Figure A 1-8 Longitudinal Profile (W-6) ...... 1-18 Figure A 1-9 Plot Plan (W-8 Rev) ...... 1-23 Figure A 1-10 Longitudinal Profile (W-8 Rev) ...... 1-23 Figure A 1-11 Plot Plan (W-19) ...... 1-28 Figure A 1-12 Longitudinal Profile (W-19) ...... 1-28 Figure A 1-13 Plot Plan (P-15) ...... 1-31 Figure A 1-14 Longitudinal Profile (P-15) ...... 1-31 Figure A 1-15 Plot Plan (P-17) ...... 1-38 Figure A 1-16 Longitudinal Profile (P-17) ...... 1-38 Figure A 1-17 Plot Plan (P-26) ...... 1-43 Figure A 1-18 Longitudinal Profile (P-26) ...... 1-43 Figure A 1-19 Plot Plan (P-28) ...... 1-46 Figure A 1-20 Longitudinal Profile (P-28) ...... 1-46 Figure A 1-21 Plot Plan (P-29) ...... 1-50 Figure A 1-22 Longitudinal Profile (P-29) ...... 1-50 Figure A 1-23 Plot Plan (P-29R) ...... 1-55 Figure A 1-24 Longitudinal Profile (P-29R) ...... 1-55 Figure A 1-25 Plot Plan (P-30) ...... 1-60 Figure A 1-26 Longitudinal Profile (P-30) ...... 1-60 Figure A 1-27 Plot Plan (P-34) ...... 1-64 Figure A 1-28 Longitudinal Profile (P-34) ...... 1-64 Figure A 1-29 Plot Plan (P-34_Rev) ...... 1-69 Figure A 1-30 Longitudinal Profile (P-34_Rev) ...... 1-69 Figure A 1-31 Plot Plan (P-35) ...... 1-75 Figure A 1-32 Longitudinal Profile (P-35) ...... 1-75 Figure A 1-33 Plot Plan (P-35_Rev) ...... 1-80 Figure A 1-34 Longitudinal Profile (P-35_Rev) ...... 1-80 Figure A 1-35 Geological Profile (N-S Section) ...... 1-81 Figure A 1-36 Plot Plan (P-38) ...... 1-87 Figure A 1-37 Longitudinal Profile (P-38) ...... 1-87 Figure A 1-38 Plot Plan (M-5) ...... 1-91 Figure A 1-39 Longitudinal Profile (M-5) ...... 1-91 Figure A 1-40 Plot Plan (M-6) ...... 1-96 Figure A 1-41 Longitudinal Profile (M-6) ...... 1-96 Figure A 1-42 Plot Plan (M-6_Rev3) ...... 1-100 Figure A 1-43 Longitudinal Profile (M-6_Rev3) ...... 1-100 Figure A 1-44 Plot Plan (M-11_Rev) ...... 1-105 Figure A 1-45 Longitudinal Profile (M-11_Rev) ...... 1-105 Figure A 1-46 Plot Plan (M-17) ...... 1-109 Figure A 1-47 Longitudinal Profile (M-17) ...... 1-109 Figure A 1-48 Plot Plan (M-18) ...... 1-113 Figure A 1-49 Longitudinal Profile (M-18) ...... 1-113 Figure A 1-50 Plot Plan (C-10) ...... 1-124

iii Power System Master Plan 2040 Final Report Appendix

Figure A 1-51 Longitudinal Profile (C-10) ...... 1-124 Figure A 1-52 Plot Plan (K-13_Rev)...... 1-131 Figure A 1-53 Longitudinal Profile (K-13_Rev) ...... 1-131 Figure A 1-54 Plot Plan (K-15) ...... 1-137 Figure A 1-55 Longitudinal Profile (K-15) ...... 1-137 Figure A 1-56 Plot Plan (G-6) ...... 1-143 Figure A 1-57 Longitudinal Profile (G-6) ...... 1-143 Figure A 1-58 Plot Plan (G-7) ...... 1-150 Figure A 1-59 Longitudinal Profile (G-7_Rev)...... 1-150 Figure A 1-60 Plot Plan (G-9) ...... 1-152 Figure A 1-61 Plot Plan (G-10 Rev2)...... 1-158 Figure A 1-62 Longitudinal Profile (G-10_Rev2) ...... 1-158 Figure A 1-63 Plot Plan (G-11_Rev2)...... 1-164 Figure A 1-64 Longitudinal Profile (G-11_Rev2) ...... 1-164 Figure A 1-65 Plot Plan (G-13) ...... 1-168 Figure A 1-66 Longitudinal Profile (G-13) ...... 1-168 Figure A 1-67 Plot Plan (G-14_Rev)...... 1-173 Figure A 1-68 Longitudinal Profile (G-14_Rev2) ...... 1-173 Figure A 1-69 Plot Plan (G-16) ...... 1-176 Figure A 1-70 Longitudinal Profile (G-16) ...... 1-176 Figure A 1-71 Plot Plan (G-19) ...... 1-180 Figure A 1-72 Longitudinal Profile (G-19) ...... 1-180 Figure A 1-73 Plot Plan (G-19) ...... 1-186 Figure A 1-74 Longitudinal Profile (G-19) ...... 1-186 Figure A 1-75 Plot Plan (N-1) ...... 1-189 Figure A 1-76 Longitudinal Profile (N-1) ...... 1-189 Figure A 1-77 Plot Plan (N-2) ...... 1-193 Figure A 1-78 Longitudinal Profile (N-2) ...... 1-193 Figure A 1-79 Plot Plan (N-3) ...... 1-197 Figure A 1-80 Longitudinal Profile (N-3) ...... 1-197 Figure A 1-81 Geological Cross Section (N-3_Rev) ...... 1-198 Figure A 1-82 Plot Plan (N-3 Rev2) ...... 1-202 Figure A 1-83 Longitudinal Profile (N-3) ...... 1-202 Figure A 1-84 Geological Cross Section (N-3_Rev2) ...... 1-203 Figure A 4-1 PSS/E Power Flow Analysis Result (2035-Base) ...... 4-2 Figure A 4-2 PSS/E Power Flow Analysis Result (2035-Dry Season) ...... 4-3 Figure A 4-3 PSS/E Power Flow Analysis Result (2035-110%) ...... 4-4 Figure A 4-4 PSS/E Power Flow Analysis Result (2040-Base) ...... 4-5 Figure A 4-5 PSS/E Power Flow Analysis Result (2040-Dry Season) ...... 4-6 Figure A 4-6 PSS/E Power Flow Analysis Result (2040-110%) ...... 4-7 Figure A 4-7 PSS/E Power Flow Analysis Result (2050-Base) ...... 4-8 Figure A 4-8 PSS/E Power Flow Analysis Result (2050-Dry Season) ...... 4-9 Figure A 4-9 PSS/E Power Flow Analysis Result (2050-110%) ...... 4-10 Figure A 4-10 Future Designed Grid (2050) ...... 4-12 Figure A 4-11 System Map (in 2035)...... 4-13 Figure A 4-12 System Map (in 2040)...... 4-14 Figure A 4-13 System Map (in 2050)...... 4-15 Figure A 4-14 Single Line Diagram (2030) ...... 4-17 Figure A 4-15 Single Line Diagram (2035) ...... 4-18 Figure A 4-16 Single Line Diagram (2040) ...... 4-19 Figure A 4-17 Single Line Diagram (2050) ...... 4-20 Figure A 5-1 General Plan Dorokha (A-8) ...... 5-2 Figure A 5-2 Dam and Intake Dorokha (A-8) ...... 5-3

iv Power System Master Plan 2040 Final Report Appendix

Figure A 5-3 Profile of Intake Dam Dorokha (A-8) ...... 5-4 Figure A 5-4 Powerhouse and Switchyard Dorokha (A-8) ...... 5-5 Figure A 5-5 General Plan Pinsa (P-30) ...... 5-7 Figure A 5-6 Dam and Intake Pinsa (P-30) ...... 5-8 Figure A 5-7 Profile of Intake Dam Pinsa (P-30) ...... 5-9 Figure A 5-8 Powerhouse and Switchyard Pinsa (P-30) ...... 5-10 Figure A 5-9 General Plan Chamkharchhu-II (C-10) ...... 5-12 Figure A 5-10 Dam and Intake Chamkharchhu-II (C-10) ...... 5-13 Figure A 5-11 Profile of Intake Dam Chamkharchhu-II (C-10) ...... 5-14 Figure A 5-12 Powerhouse and Switchyard Chamkharchhu-II (C-10) ...... 5-15 Figure A 6-1 Locations of Potential PSPP Sites ...... 6-2 Figure A 6-2 Plot Plan (Pangbang PSPP)...... 6-3 Figure A 6-3 Plot Plan (Jerichhu PSPP) ...... 6-8 Figure A 6-4 Longitudinal Profile (Jerichhu PSPP Alt.3) ...... 6-8 Figure A 6-5 Plot Plan (Basochhu PSPP) ...... 6-12 Figure A 6-6 Longitudinal Profile (Basochhu PSPP) ...... 6-12 Figure A 8-1 Enlarged version of Figure 5-18 ...... 8-2 Figure A 8-2 Enlarged version of Figure 5-19 ...... 8-3 Figure A 8-3 Enlarged version of Figure 5-20 ...... 8-4 Figure A 8-4 Enlarged version of Figure 5-21 ...... 8-5 Figure A 8-5 Enlarged version of Figure 5-22 ...... 8-6 Figure A 8-6 Enlarged version of Figure 7-4 ...... 8-7 Figure A 8-7 Enlarged version of Figure 9-8 ...... 8-8 Figure A 8-8 Enlarged version of Figure 9-13 ...... 8-9 Figure A 8-9 Enlarged version of Figure 9-26 ...... 8-10

List of Tables

Table A 2-1 1st MCA Score Table (Technical – Part 1/2) ...... 2-2 Table A 2-2 1st MCA Score Table (Technical – Part 2/2) ...... 2-3 Table A 2-3 1st MCA Score Table (Technical – Part 1/2) ...... 2-4 Table A 2-4 1st MCA Score Table (Technical – Part 2/2) ...... 2-5 Table A 2-5 1st MCA Score Table (Economic – Part 1/3) ...... 2-6 Table A 2-6 1st MCA Score Table (Economic – Part 2/3) ...... 2-7 Table A 2-7 1st MCA Score Table (Economic – Part 3/3) ...... 2-8 Table A 2-8 1st MCA Score Table (Environment – Part 1/2) ...... 2-9 Table A 2-9 1st MCA Score Table (Environment – Part 2/2) ...... 2-10 Table A 2-10 1st MCA Score Table (Social environment – Part 1/2) ...... 2-11 Table A 2-11 1st MCA Score Table (Social environment – Part 2/2) ...... 2-12 Table A 2-12 1st MCA Score Table (Natural environment – Part 1/3) ...... 2-13 Table A 2-13 1st MCA Score Table (Natural environment – Part 2/3) ...... 2-14 Table A 2-14 1st MCA Score Table (Natural environment – Part 3/3) ...... 2-15 Table A 2-15 1st MCA Score Table (Social development – Part 1/3) ...... 2-16 Table A 2-16 1st MCA Score Table (Social development – Part 2/3) ...... 2-17 Table A 2-17 1st MCA Score Table (Social development – Part 3/3) ...... 2-18 Table A 2-18 2nd MCA Score Table (Technical) ...... 2-20 Table A 2-19 2nd MCA Score Table (Technical – Part 1/2) ...... 2-21 Table A 2-20 2nd MCA Score Table (Technical – Part 2/2) ...... 2-22 Table A 2-21 2nd MCA Score Table (Economic – Part 1/2) ...... 2-23 Table A 2-22 2nd MCA Score Table (Economic – Part 2/2) ...... 2-24 Table A 2-23 2nd MCA Score Table (Environment) ...... 2-25 Table A 2-24 2nd MCA Score Table (Social environment – Part 1/2) ...... 2-26 Table A 2-25 2nd MCA Score Table (Social environment – Part 2/2) ...... 2-27

v Power System Master Plan 2040 Final Report Appendix

Table A 2-26 2nd MCA Score Table (Natural environment – Part 1/2) ...... 2-28 Table A 2-27 2nd MCA Score Table (Natural environment – Part 2/2) ...... 2-29 Table A 2-28 2nd MCA Score Table (Social development – Part 1/2) ...... 2-30 Table A 2-29 2nd MCA Score Table (Social development – Part 2/2) ...... 2-31 Table A 3-1 Ambient Air Quality Standards ...... 3-1 Table A 3-2 Noise Level Limits ...... 3-1 Table A 3-3 Urban Drinking Water Supply (Water Quality Standard) ...... 3-1 Table A 3-4 Mammals: 25 species ...... 3-2 Table A 3-5 Birds: 19 species ...... 3-2 Table A 3-6 Reptiles: 3 species ...... 3-3 Table A 3-7 Amphibians: 1 species...... 3-3 Table A 3-8 Other Vertebrates: 1 species...... 3-3 Table A 3-9 Plants: 43 species ...... 3-3 Table A 6-1 Criteria for Identifying Potential Pumped Storage Projects ...... 6-1 Table A 7-1 Number table for Financial analysis (G-G Scheme) ...... 7-2 Table A 7-2 Number table for Financial analysis (ODA Scheme) ...... 7-3 Table A 7-3 Number table for Financial analysis (PPP Scheme – Part 1/2) ...... 7-4 Table A 7-4 Number table for Financial analysis (PPP Scheme – Part 2/2) ...... 7-5 Table A 7-5 Number table for Financial analysis (IPP Scheme - 1) ...... 7-6 Table A 7-6 Number table for Financial analysis (IPP Scheme - 2) ...... 7-7 Table A 7-7 Number table for Financial analysis (IPP Scheme – 3) ...... 7-8 Table A 7-8 Number table for Financial analysis (G-G Scheme (Delay)) ...... 7-9 Table A 7-9 Number table for Financial analysis (ODA Scheme (Delay)) ...... 7-10 Table A 7-10 Number table for Financial analysis (PPP Scheme (Delay) – Part 1/2) ...... 7-11 Table A 7-11 Number table for Financial analysis (PPP Scheme (Delay) – Part 2/2) ...... 7-12 Table A 7-12 Number table for Financial analysis (IPP Scheme - 1 (Delay)) ...... 7-13 Table A 7-13 Number table for Financial analysis (IPP Scheme - 2 (Delay)) ...... 7-14 Table A 7-14 Number table for Financial analysis (IPP Scheme - 3 (Delay)) ...... 7-15 Table A 7-15 Number table for Financial analysis (ODA Scheme (RP)) ...... 7-16 Table A 7-16 Number table for Financial analysis (PPP Scheme (RP) – Part 1/2)...... 7-17 Table A 7-17 Number table for Financial analysis (PPP Scheme (RP) – Part 2/2)...... 7-18

vi Power System Master Plan 2040 Final Report Appendix

Appendix-1 Results of Site Reconnaissance

1.1 A-4: Kunzangling

Project Name A-4: Kunzangling Date 19, 20/11/2018 Basin Amochhu Tributary Amochhu Dam (Weir) Latitude: 27° 17' 41.28" N Longitude: 89° 0' 37.82" E

Powerhouse Latitude: 27° 10' 50.91" N Longitude: 89° 1' 11.84" E Type ROR+Pond RBL at Dam EL 2,060 m Installed Dam/Weir 897 MW 66 (21) m Capacity Height

Primary Data Max. 141 m3/s Salient Crest Length 160 m General Discharge Features Features Effective Waterway 737.2 m 14,839 m Head Length Catchment Live Storage 2,100 km2 1.1 MCM Area Capacity Elongation from Dam site: more than 15 km from the Powerhouse Site Existing Road Powerhouse Site: 1 bridge and 8 km

Access

River Flow Rate (Eye Measurement)

Hydrology Sediment General Geology Geofacies (compiled by Long et al., 2011) are as follows: The subsurface geology of the project area belongs to the Lower metasedimentary unit in the Structurally-lower Greater Himalayan section in the Greater Himalayan Zone of the Neoproterozoic-Cambrian [?] period. Dominantly amphibolite-facies (Gansser, 1983; Grujic et al., 2002; Daniel et al., 2003) metasedimentary rocks, including quartzite, and biotite-muscovite-garnet schist and paragneiss often exhibiting kyanite, sillimanite, or staurolite, and partial melt textures** (Long and McQuarrie, 2010). Orthogneiss intervals locally split out. Up to ~5.0 km- thick; thickens toward western Bhutan.

Geography / Geology Dam / Intake Waterway Powerhouse

1 Power System Master Plan 2040 Final Report Appendix

Natural Park / Protected  Site is designated as a Protected Area (Jigme Khesar Strict Nature Area Reserve) which has an abundant variety of genetic species and ecosystem diversity of global importance.  Zoning categories have not been adopted. However, there is an idea for zoning categories based on the environment management plan, in which the project site belongs to the core zone.  A revision of the Act (Forest and Nature Conservation Act 1995) is being prepared to prohibit all human activities other than research and studies on natural science within the Strict Nature Reserve.  There is a holy lake with wetland (less than 1ha) near the upstream of the project site.

Prosperous fauna / flora  With the construction of the pond, cool broad-leaved forest and mixed conifer forest with rare species of Cordyceps, Snow down Lily, Blue Poppy, Ginseng and Rhuemnobile growing under forest designated as protected plants by the FNCR (Forest and Nature Conservation Rules of Bhutan) will be submerged.

 The main endangered species designated by the IUCN at the project

site, according to interviews with park officers (JKSNR park office), are Red Panda (EN), Gaur (VU), Wild Yak (VU), Dhole (EN), Chinese Pangolin (CR), Leopard (VU), Asiatic Black Bear (VU), and Rufous- necked Hornbill (VU).

 In terms of endangered Fish species, Golden Mahseer (EN), and Schizothorax richardsonii (VU) have been confirmed (result of interview at JKSNR park office).

Resettlement /  N/A

Natural / Social Environment Compensatory assets Historical / Cultural  N/A Heritage Other  All human activities other than research and studies on natural science within the Strict Nature Reserve have been strictly prohibited in principle so far (result of interview at JKSNR park office).

 The officials welcome the idea of constructing a HEP as they believe that the project would improve their local economy and the livelihoods of local people, and said that local people would cooperate with the survey implementation as long as their private land is not disturbed or occupied.

 Project facilities are located in Sombaykha Gewog, where the poverty rate is much worse than the overall Haa Dzongkhag. The local people expect the extension of farm roads if the project is implemented. If the roads to Haa town and Phuentsholing are further improved using the project budget, they will gain increased access to local products.

1-2 Power System Master Plan 2040 Final Report Appendix

Figure A 1-1 Plot Plan (A-4)

Figure A 1-2 Google Earth Image (A-4)

1-3 Power System Master Plan 2040 Final Report Appendix

1.2 A-5: Tingma_Rev

Project Name A-5: Tingma_Rev Date 20/11/2018 Basin Amochhu Tributary Amochhu Dam (Weir) Latitude: 27° 12' 34.21" N Longitude: 89° 1' 20.35" E

Powerhouse Latitude: 27° 9' 15.93" N Longitude: 89° 4' 35.82" E Type ROR RBL at Dam EL 1,520 m Installed Dam/Weir 816 MW 45 (10) m Capacity Height

Primary Data Max. 148 m3/s Salient Crest Length 70 m General Discharge Features Features Effective Waterway 638.3 m 13,806 m Head Length Catchment Live Storage 2,208 km2 MCM Area Capacity Elongation from Existing 5 hours by car from Haa to Sombaykha Road Dam Site: 15km Access Powerhouse Site: 15km

River Flow Rate 35 - 40 m3/s (Eye Measurement)

Hydrology Sediment 0.5 – 1.0 m (Boulder) General Geology Geofacies (compiled by Long et al., 2011) are as follows: The subsurface geology of the project area belongs to the Lower metasedimentary unit in the Structurally-lower Greater Himalayan section in the Greater Himalayan Zone of Neoproterozoic-Cambrian [?] period. Dominantly amphibolite-facies (Gansser, 1983; Grujic et al., 2002; Daniel et al., 2003) metasedimentary rocks, including quartzite, and biotite- muscovite-garnet schist and paragneiss often exhibiting kyanite, sillimanite, or staurolite, and partial melt textures** (Long and McQuarrie, 2010). Orthogneiss intervals locally split out. Up to ~5.0 km-thick; thickens toward western Bhutan.

 No geographic problems which imply a land slide and/or mass rock creeping were observed during the site reconnaissance. However, thick unconsolidated deposits were observed in the many places.  No clear lineaments were verified.  The geologies identified on the cut slope of the roads are Schist and Gneiss. In these outcrops, weathering is remarkable with loosening in the whole area.

Geography / Geology Dam / Intake 【A-5_Rev】  Since the A-4 Site was designated as a Protected Area, it would be hard to develop. The A-5_Rev Dam site was shifted to the upmost stream outside of the Protected Area.

【A-5】Dam site was observed with a drone.  There is a possibility that the right bank slope of the dam axis may be of collapsed ruins. However, the vegetation has recovered now, and it is estimated that the progress of the collapse is small (Photo 1).  A knick line (concave) is observed in the upper area of the above slope that might be a moved rock mass. (A-4 outlet site is located at the same place) (Photo 1)

1-4 Power System Master Plan 2040 Final Report Appendix

Waterway  The geology along the waterway is assumed to be Schist and Gneiss judging from the outcrops on the cut slope of the road (Photo 2). The overall geological structure is NW-SE strike and it gently slopes to the north (Photo 3). In the vicinity of the riverbed, Schist and Gneiss form a steep cliff (Photo 4).  Rock classification point of the waterway is 58 as RMR criteria and Class-III.

Powerhouse 【A-5_Rev】 Observed with drone  Ground surface of the ridge of the powerhouse is almost a uniform slope, and no unstable conditions were verified (Photos 4, 5).

【A-5】  Powerhouse is planned to be located in the ridge that forms a steep cliff.  Collapsed land exists on part of the slope (Photo 6).  Unconsolidated deposits are observed on the cut slope of the road (Photo 7).  Since the terrain near the outlet site has a lineament, there is a possibility of it being a fault. However, since the water outlet is far from the lineament, it is judged that there are no particular problems.

Natural Park / Protected  The project area is outside any protected area, but there is a Protected Area Area (Jigme Khesar Strict Nature Reserve) upstream of the pond site.

Prosperous fauna / flora  With the construction of the pond, cool broad-leaved forest associated with Java ceder, Castanopsis indica, Acer species and mixed conifer forest associated with Chir pine, and Cycas pectinata are submerged (result of interview with forest office staff).  In terms of the main endangered species designated by the IUCN, according to interviews with park officers, Leopard (VU), Asiatic Black Bear (VU), Rufous-necked Hornbill (VU) have been confirmed at the project site.  Migration of Fish (Golden Mahseer (EN) and Schizothorax richardsonii

(VU)) has been confirmed (result of interview with forest office staff).

Resettlement /  N/A Compensatory assets Historical / Cultural  N/A Heritage Other  The introduction of mitigation equipment to the Dam for fish migration is advisable to avoid adverse impacts on the ecosystem of the Protected Area (Jigme Khesar Strict Nature Reserve).

Natural / Social Environment  Gewog officers said that local people would cooperate with the survey implementation as long as their private land is not disturbed or occupied.

 Project facilities are located in Sombaykha Gewog, where the poverty rate is much worse than the whole Haa Dzongkhag. If the roads to Haa town and Phuentsholing are further improved using the project budget, they will gain increased ability to obtain and sell local products.

 There is an idea for a trekking plan from Sombaykha Gewog to Nakha, Sonnapata Lake up to Haa in the near future. Further analysis is required.

1-5 Power System Master Plan 2040 Final Report Appendix

Dam

Photo 1 A-5 Dam Site

Photo 2 Outcrops along the road (Schist weathered) Photo 3 Structure of sound rock (NW-SE strike, N dip)

Surge Tank

Photo 4 A-5_Rev Panoramic view around Surge Tank

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Photo 6 A-5 Slope collapse around Powerhouse Powerhouse

Photo 5 A-5_Rev Panoramic view around Photo 7 A-5 Unconsolidated Deposits around Powerhouse Powerhouse

1-7 Power System Master Plan 2040 Final Report Appendix

Figure A 1-3 Plot Plan (A-5_Rev)

GHlml

Figure A 1-4 Longitudinal Profile (A-5_Rev)

1-8 Power System Master Plan 2040 Final Report Appendix

1.3 A-8: Dorokha

Project Name A-8: Dorokha Date 21/11/2018 Basin Amochhu Tributary Amochhu Dam (Weir) Latitude: 27° 8'12.27"N Longitude: 89° 8'5.19"E Powerhouse Latitude: 27° 2'19.09"N Longitude: 89°12'34.28"E

Type ROR+Pond RBL at Dam EL 840 m Installed Dam/Weir 550 MW 84 (27) m Capacity Height

Primary Data Max. Salient 174.8 m3/s Crest Length 210 m General Discharge Features Features Effective Waterway 364.6 m 14,187 m Head Length Catchment Live Storage 2,602 km2 7.9 MCM Area Capacity Elongation from Existing 1.5 hours by car from Sombaykha to Dam Site Road Dam Site: 2 km Access Powerhouse Site: 1 bridge and 0.5 km

River Flow Rate 40 - 50 m3/s (Eye Measurement)

Hydrology Sediment 0.5 – 1.0 m (Boulder) General Geology Geofacies (compiled by Long et al., 2011) are as follows: The subsurface geology of the project area belongs to the Lower metasedimentary unit in the Structurally-lower Greater Himalayan section in the Greater Himalayan Zone of the Neoproterozoic-Cambrian [?] period. Dominantly amphibolite-facies (Gansser, 1983; Grujic et al., 2002; Daniel et al., 2003) metasedimentary rocks, including quartzite, and biotite-muscovite-garnet schist and paragneiss often exhibiting kyanite, sillimanite, or staurolite, and partial melt textures** (Long and McQuarrie, 2010). Orthogneiss intervals locally split out. Up to ~5.0 km- thick; thickens toward western Bhutan.

 There are many places where steep cliffs are formed across the whole area in this site.  No unstable slopes which imply an apparent lineament, a land slide and/or mass rock creeping were observed during the site reconnaissance. However, thick unconsolidated deposits were observed at many places.  Schist and Gneiss are distributed from Dam site to Waterway route. Geography / Geology Long’s Geological map shows that a thrust fault is distributed in the central part of the waterway, but clear ones were not verified.

Dam / Intake Observed with drone  The terrain around the dam site forms a steep cliff on both banks (Photo 1).  Schist and Gneiss are distributed downstream of the Dam site (Photo 2, 3).  The overall geological structure is NW-SE strike and 10 - 20NE dip.  The riverbed gravel is thickly deposited downstream of the dam axis (Photo 4).  Sediment discharged from the creek on the left bank and riverbed

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gravel is thickly deposited on the left bank side riverbed to the right upstream of the dam axis (Photo 5).

Waterway Observed from the road on the right bank  Geology along the waterway route seems to be Schist and Gneiss, which often form steep cliffs throughout the whole area (Photo 6). RMR evaluation point marks 67 and the rock classification is mainly Class-II.

Powerhouse Observed with drone  The ridge of the power station's surface shows a steep terrain, and no unstable situations are observed (Photo 7, 8).  Geology around the powerhouse seems to be Schist and Gneiss.

Natural Park / Protected  The project area is outside any protected area. Area Prosperous fauna / flora  The Dam site is covered by herbaceous plants such as White Snakeroot (Compositae) and broad-leaved trees such as Bischofia javanica, Trevesia palmata. However, these trees will not be submerged as the high-water level is under the tree zone.  In terms of the main endangered species designated by the IUCN, according to interviews with forest officers, Leopard (VU), Tiger (EN), Rufous-necked Hornbill (VU) have been confirmed at the project site (result of interview with Park office staff).  In terms of endangered Fish species, Golden Mahseer (EN) has been confirmed (result of interview with forest office staff).

Resettlement /  N/A. Compensatory assets Historical / Cultural  N/A. Heritage Other  The wide river (over 100m) will help to avoid submerging the surrounding natural environmental.  Poverty rates of the local area are far worse than the Haa Dzongkhag

Natural / Social Environment poverty level. If the project is implemented, local people expect improvements in local markets, better local business and job opportunities which would improve their livelihoods.

 There are 17 activities under the 12th 5 year plan, in areas such as construction, road soling & maintenance, monsoon restoration of farm roads, and rehabilitation of water sources.

 8 acres of private land (barren land) is present on the two river basins near the suspension bridge (1km downstream of dam site). Its owners (3 to 4 HHs) live in Putsena village, 1.5km south of the dam site.

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Photo 1 Dam Site Photo 2 Outcrop of Right Bank

Photo 3 Outcrop of Left Bank Photo 4 Riverbed Gravels (Downstream of Dam)

Photo 5 Riverbed Gravels (Upstream of Dam)

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Photo 6 Topography of Waterway Route

Photo 7 Ground Surface of Powerhouse Photo 8 Outlet Site

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Figure A 1-5 Plot Plan (A-8)

Thrust ?

Thrust ?

Figure A 1-6 Longitudinal Profile (A-8)

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1.4 W-6: Chuzom

Project Name W-6: Chuzom Date 10/12/2018 Basin Wangchhu Tributary Wangchhu Dam (Weir) Latitude: 27° 18' 41.83" N Longitude: 89° 32' 50.47" E

Powerhouse Latitude: 27° 16' 28.44" N Longitude: 89° 32' 0.96" E Type Reservoir RBL at Dam EL 2,059m Installed Dam/Weir 152 MW 206 (40) m Capacity Height

Primary Data Max. 94.5 m3/s Salient Crest Length 550 m General Discharge Features Features Effective Waterway 186.0 m 4,486 m Head Length Catchment Live Storage 2,483 km2 370.6 MCM Area Capacity Elongation from Existing Dam site and powerhouse site: Accessible through the existing main road. Road Access General Geology Geofacies (compiled by Long et al., 2011) are as follows: The subsurface geology of the project area falls in the Middle unit of the Paro Formation (Pzpm), for which the geological age ranges from the Cambrian to the Ordovician period. Gray to tan, thin-bedded, fine-

grained, micaceous quartzite, interbedded with biotite-garnet-muscovite schist, rare calc-silicate rocks, and marble. Contact with schist of the lower unit is gradational. Two white to gray, medium crystalline marble marker beds are divided out. White to gray, medium-crystalline marble marker bed (m1; 10m thick) is interbedded.

 The above mentioned medium crystalline marble (m1) could not be

Geography / Geology observed on the cut slope of the N-S direction main road.  Thick overburden due to past debris flow is distributed widely around the project area. Some outcrops for which debris flow had eroded the old terrace were observed.

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Dam / Intake  The dam site is located just downstream of the confluence point of Wangchhu and Parochhu.  Topography of the dam and intake site is V-shaped and is around 55 degrees up to 100m high from the river bottom, and yet the higher slope is gentle at around 30 degrees (Photo 1).  Schist or Quartzite, which strike and dip (EW/20S), are observed on the right bank. However, the rock seems moderately weathered even in the riverbed. Huge boulders are scattered, and their surface shows dirt (Photo 2).  Since the subsurface of the dam site is covered by thick overburden, such as debris flow and terrace deposits, it is assumed that the excavation volume for the dam foundation will be huge.  In addition, thick overburden is observed not only at the dam site but also on the slopes surrounding the reservoir area. Impoundment of the reservoir may cause instability in the slopes surrounding the reservoir. Most probably, there may be landslides into the reservoir, bringing about instability of the dam and a reduction of storage capacity in the reservoir.  Construction material for dam construction could be developed at the confluence point of Thimphuchhu and Parochhu. However, the yielding percentage might be low, since most of the outcrops in this area are moderately weathered and flaggy.

Waterway  The surface of the slope is covered with sparse forest. Fresh rock outcrops are scarcely observed on the right bank of Wangchhu where the waterway is planned to run.  The rock classification along most of the headrace tunnel is estimated as mainly Class-III: Fair rock whose RMR value is estimated as 53.

Powerhouse  The geology surrounding the underground powerhouse seems to be schist dominated. A moderately weathered outcrop of schist and quartzite is observed on the slope at the powerhouse site (Photo 5). The schist and quartzite alternate with a thickness of 2-5m for quartzite and 1m for schist. The rock’s hardness seems to be “R4; strong”1. However, joints might exist frequently. Detailed geological investigation is required to examine the lithology and geotechnical conditions surrounding the cavern.

Natural Park / Protected  The project area is outside of any protected area. Area Prosperousment fauna / flora  The project area is covered by Blue Pine Forest. The forest has been severely degraded by human activities. Social Natural /  According to the Territorial Office at Paro, there are no endangered Environ species in the project area because of the degraded environment.

1 Hand-held specimens require more than one blow of a geological hammer to fracture them.

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Resettlement / According to the GIS data from NLC and an interview with Paro Dzongkhag, Compensatory assets at least the following impacts can occur at the dam site, reservoir area, and PH site.  220 resettlements, including houses, will be required due to the reservoir. In the Isuna village alone, there would be almost 70+ households displaced.  Approx. 594 acres of private land acquisition will be required. In the Shaba village stretch alone, approximately 100 acres of wetland (paddy field) would be lost.  Almost 30+ km of National Highway, from Paro airport to Thimphu, would be submerged. Isuna Bridge and Chuzom Bridge would be submerged.

Historical / Cultural  According to the GIS data from NLC, 27 cultural heritage sites, Heritage including “Tachog Lhakhang” and the “Tachog Suspension Bridge”, which are considered nationally important, would be submerged.

Other  Paro Dzongkhag Administration remarked that development of this site wouldn’t be possible just because of the immense loss of wetlands (paddy field) and the huge amount of resettlement that would be required, including reconstruction of major government installations.

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Photo 1 Dam Site Photo 2 View of Riverbed at Dam Site

Photo 3 Right bank of Dam Site Photo 4 Thick Overburden at Dam Site

Photo 5 Outcrop above the Powerhouse Site Photo 6 View of riverbed at Powerhouse Site

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Figure A 1-7 Plot Plan (W-6)

Figure A 1-8 Longitudinal Profile (W-6)

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1.5 W-8: Zangkhepa

Project Name W-8: Zangkhepa_Rev Date 10/12/2018 Basin Wangchhu Tributary Parochhu Dam (Weir) Latitude: 27° 34' 55.26" N Longitude: 89° 17' 37.14" E

Powerhouse Latitude: 27° 29' 10.90" N Longitude: 89° 20' 30.04" E Type ROR RBL at Dam EL 2,700m Installed Dam/Weir 54 MW 5 m Capacity Height

Primary Data Max. Crest 21.6 m3/s Salient 30 m General Discharge Features Length Features Effective Waterway 288.3 m 12,696 m Head Length Catchment Live Storage 471 km2 MCM Area Capacity Elongation from Existing Dam site: Accessible using the existing road Road (improvement of 10km-long existing road is required) Powerhouse Site: 1 bridge and improvement of 1km of existing road is

Access required

General Geology Geofacies (compiled by Long et al., 2011) are as follows: The subsurface geology of the project area falls in the Structurally-lower Greater Himalayan section in the Greater Himalayan Zone of the Neoproterozoic-Ordovician [?] period. The upper half of the waterway route belongs to the Upper metasedimentary unit (GHlmu), with variable metamorphic grades, and dominantly amphibolite facies (Gansser, 1983), partial melt- and often kyanite-, sillimanite-, or staurolite-bearing paragneiss, schist, and quartzite in the east (Grujic et al., 2002) and near base in west-central Bhutan, and melt-free, dominantly upper greenschist-facies (Gansser,

1983) quartzite and biotite-muscovite-garnet schist in central Bhutan (Long and McQuarrie, 2010). The lower half of the waterway route belongs to the Orthogneiss unit (GHlo) from the Cambrian to the Ordovician Period, and the Lower metasedimentary unit (GHlml) from the Neoproterozoic to the Cambrian [?] period. The Orthogneiss unit (GHlo) consists of Cliff-forming, massive-

Geography / Geology weathering, granite-composition orthogneiss; generally, it exhibits leucosomes and abundant feldspar augen. Paragneiss, schist, and quartzite intervals locally split out. Interpreted as deformed Cambrian- Ordovician granite plutons that intruded Greater Himalayan sedimentary protoliths thickens toward eastern Bhutan. The Lower metasedimentary unit (GHlml) consists mostly of amphibolite-facies metasedimentary rocks, including quartzite, and biotite-muscovite- garnet schist and paragneiss often exhibiting kyanite, sillimanite, or staurolite, and partial melt textures. Orthogneiss intervals locally split out.

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Weir / Intake  Since the original weir site was located in a Protected Area and was hard to develop, the Dam site is shifted to the upmost stream outside of the Protected Area.  In addition, the weir site is positioned just upstream of the flat terrace on the left bank, where the open-air settling basin could be installed.  The geography of the weir site is gentle (around 20 degrees), and both right and left slopes are cultivated for terraced paddy fields.  No bedrock could be observed on the left bank of the site.

Waterway  The waterway route is positioned on the left bank to avoid impacts on the Jigme Dorji National Park Corridor.  A length of about 100m for the headrace from the desilting basin should be a culvert, since the overburden is composed of gravelly soil, which is deposited with a thickness of about 30m. Excavation for an underground type desilting basin is very hard, since such overburden contains huge, hard bounding stones.  The subsurface geology along the tunnel route belongs to the Structurally-lower Greater Himalayan section. That is, gneissoid bedrock such as orthogneiss, paragneiss, schist, or quartzite. Therefore, these geological conditions may be preferable for construction of the tunnel.  Weathering grade along the headrace tunnel may be Slightly Weathered (SW), and the rocks may mainly belong to Class-II rock, for which the RMR value is estimated to be 71.

Powerhouse  As the intake site location was revised to avoid impact on Jigme Dorji National Park, the powerhouse site was accordingly shifted to the downstream.  In consideration of the distance from the holy Taktsang (Tiger’s nest), the locations of the surge tank and powerhouse sites are positioned so that those facilities will be invisible to visitors. Since the geology of the sites is Gneiss, as per the waterway route, it is suitable for construction of the underground powerhouse.

Natural Park / Protected  The project area is outside of any protected area. However, the inlet Area area is very close to the Jigme Dorji National Park and a Biological Corridor (TSNR-JDNP), and the exact boundaries of these protected areas need to be verified.

Prosperous fauna / flora  The project area is covered by Blue Pine Forest.  According to the Territorial Office at Paro, Sambar (VU) and Black

Environment Bear (VU) occur in the area. In the Paro Dzongkhag area, six (6) and Natural / Social five (5) Tiger cubs were counted by the National Tiger Survey (2014- 2015).

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Resettlement / According to the GIS data from NLC and interview with Tsento Gewog, Compensatory assets  No resettlement is required; however, there are 2 HHs around the powerhouse.  No private land acquisition is required; however, the land owned by the villagers of Dangreyna under Zamsa Chiwog is located right below the area identified for the Powerhouse. There is a privately- operated sand quarry near Zamsa Village.

Historical / Cultural  According to the GIS data and interview with Tsento Gewog, no Heritage cultural heritage sites are affected directly; however, Lhedi Gompa (temple) is on a hillock which is located along the waterway and so might be affected or disturbed during construction. In addition, the very important national heritage sites of “Taktsang” and “Drugyal Dzong” (reconstruction of 17th century fortress and Buddhist monastery) are within the Gewog, although these are located far from the project site and no direct impacts would occur.

Other  The waterway passes through an area of private land.  According to Tsento Gewog officials, 7 HHs or so in the Shari Village of Tsento Gewog use private water pumps to irrigate their paddy fields from the river, Pachhu; however, their fields are located in the downstream area, where the tail race tunnel from the Powerhouse joins the Pachhu. For more detailed information about the use of irrigation water from the river when investigating the project, it is advisable to verify information from village representatives, too.

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Photo 1 Weir Site Photo 2 Distant View of Weir Site (Upstream)

Photo 3 Distant View of Weir Site (Downstream) Photo 4 Gravelly Soil distributed on Local Road

Photo 5 Gneissoid distributed above Powerhouse Photo 6 Distant View of Outlet Site

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Figure A 1-9 Plot Plan (W-8 Rev)

Figure A 1-10 Longitudinal Profile (W-8 Rev)

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1.6 W-19: Pipingchhu

Project W-19: Pipingchhu Date 22/11/2018 Name Basin Wangchhu Tributary Pipingchhu Dam (Weir) Latitude: 26° 51' 13.45" N Longitude : 89° 47' 2.830" E

Powerhouse Latitude: 26° 46' 22.10" N Longitude: 89° 44' 3.45" E Type ROR RBL at Dam EL 585 m Installed Dam/Weir 100 MW 35 (20) m Capacity Height Primary Data Max. 29.9 m3/s Salient Crest Length 80 m Discharge General Features Effective Waterway Features 386 m 13,394 m Head Length Catchment Live Storage 217 km2 MCM Area Capacity

Elongation from Existing Dam site: 20 km Road Powerhouse Site: 1 bridge and 2 km Access

3 River Flow Rate 2 – 2.5 m /s (the river water may leak to the other basin) (Eye Measurement) (Tributary downstream Wangchhu: 2 m3/s) Sediment 0.1 – 0.5 m (Boulder) Hydrology

General Geology Geofacies (compiled by Long et al., 2011) are as follows: The subsurface geology of the project area belongs to the Manas Formation in the Baxa Group in the Lesser Himalayan Zone of the Neoproterozoic-Cambrian [?] period. Gray to white, medium- to thick-bedded, medium- to coarse-grained, locally-conglomeratic quartzite exhibiting common trough cross- bedding, interbedded with dark-gray to dark-green, thin-bedded to thinly-laminated phyllite, and medium-gray dolostone (locally divided out) (Bhargava, 1995; Tangri, 1995a; Long et al., 2011A).

 In Google Earth images, a lot of NW-SE system lineaments are observed along Pipingchhu in the overall project area.  A lot of collapsed land is observed along the road.  Schist is distributed along the right bank road of Wangchhu near the Powerhouse site (Photo 3). Phylite (Photos 4, 5) and Calcareous breccia composed of breccia of Dolomite (Photos 6, 7) are

Geography / Geology distributed along the left bank road of Pipingchhu near the Powerhouse site. Taking into account Long’s geological map, the same geology is assumed to be distributed across the whole project area.  According to Long’s geological map, a thrust fault is assumed to exist around the Powerhouse site. However, no thrust fault was identified in this field survey.

Dam / Intake

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Waterway  Geology along the Waterway route was not observed. However, it is assumed that the waterway will encounter a number of thrust faults at a gentle angle in the direction of the channel. RMR evaluation point marks 48 and the rock classification is mainly Class-III. Powerhouse  The slope where the Powerhouse is planned to be located is uniformly inclined at around 45° (Photo 1).  The rock of the power station site is hard itself, but weakness is expected in some places due to the influence of a Thrust fault.

Natural Park / Protected  The project area is outside any protected area. Area Prosperous fauna / flora  The Dam site and Powerhouse site are covered with Subtropical broad-leaved forest composed of Musa balbisiana, Shorea robusta, and Acer sikkimense (interview with naturalists from Chhukka forest office)  Tiger (EN), Asian Elephant (EN) and Leopard (VU) are observed in the forests of the project site.  An endangered species of Fish, Golden Mahseer (EN), has been confirmed near the outlet of powerhouse.

Resettlement / Compensatory assets  Unknown as it is not accessible.

 Private houses (10 structures) and farmland are on the surface of the PH site.  Maize, millet, orange, sugarcane, banana, jackfruit, mango, and papaya will be damaged if the PH is constructed on the surface.  A few types of livestock, such as ox, cow and hen, are raised in the village.

Natural / Social Environment  Teak is produced in the village.

Historical / Cultural  There is a nationally important cultural heritage site named Heritage "Jimechunye", 500m southeast of the PH. It attracts local tourists, and they are examining how they should promote international tourism. Tourism is one of the major programs in the upcoming 5 year plan.

Other  The existing road and bridge will be submerged, which will impact the neighboring villages.

Other (Special Note)  The locations of Wangchhu HPP and W19 are close each to other in the same village. Wangchhu HPP's PH is planned to be on the surface, and negotiation with local people regarding land acquisition and resettlement is presently on-going. Local people are happy and willing to cooperate because substitute land will be given with favorable conditions (more fertile land will be provided in the same village, or same gewog), together with crop compensation.

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Surge Tank

Pipingchhu

Wangchhu

Photo 1 Powerhouse Site

Surge Tank

Pipingchhu Wangchhu

Photo 2 Surge Tank & Powerhouse Site Photo 3 Geology along Road (Schist)

Photo 4 Geology along Road (Phyllite) Photo 5 Close-up Photo

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Photo 6 Geology along Road (Calcareous Breccia) Photo 7 Geology along Road (Calcareous Breccia)

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Figure A 1-11 Plot Plan (W-19)

Pzm Pzm

thrust fault? thrust fault? thrust fault?

Figure A 1-12 Longitudinal Profile (W-19)

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1.7 P-15: Tamigdamchu

Project Name P-15: Tamigdamchu Date Basin Punatsangchhu Tributary Phochhu Latitude: 27° 41' 53.19" N Longitude: 89° 58' 54.39" E Dam (Weir) 27° 41' 21.69" N 89° 57' 29.26" E

Powerhouse Latitude: 27° 40' 51.39" N Longitude: 89° 56' 20.04" E EL 1,540 m Type ROR+Pond RBL at Dam EL 1,555 m Installed Dam/Weir 60 (40) m 188 MW Capacity Height 5 m Primary Data Max. Salient 80 m 156.5 m3/s Crest Length General Discharge Features 40 m Features Effective Waterway 139.5 m 4,993 m Head Length Catchment Live Storage 2,120 km2 MCM Area Capacity Elongation from Existing Road Access

River Flow Rate (Eye Measurement)

Hydrology Sediment General Geology Geofacies (compiled by Long et al., 2011) are as follows: Subsurface geology of the project area belongs to the Upper metasedimentary unit (GHlmu) in the Structurally-lower Greater Himalayan section in the Greater Himalayan Zone of the

Neoproterozoic-Ordovician [?] period. Variable metamorphic grades; dominantly amphibolite facies (Gansser, 1983), partial melt- and often kyanite-, sillimanite-, or staurolite-bearing paragneiss, schist, and quartzite in east (Grujic et al., 2002) and near base in west-central Bhutan, and melt-free, dominantly upper greenschist-facies (Gansser, 1983) quartzite and biotite- muscovite-garnet schist in central Bhutan (Long and McQuarrie, 2010). Geography / Geology Dam / Intake Waterway Powerhouse Natural Park / Protected  Project site is designated as a Protected Area (Jigme Dorji National

l nt

al / Area Park). Socia Envir onme Natur

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Prosperous fauna / flora  Dam site, Waterway, and Powerhouse site are covered with primeval forest of Chir pine composed of Pinus roxburghii and Cycas pectinate, and warm broad-leaved forest composed of Bischofia javanica and Castanopsis indica (observation results from a distant place outside of National Park boundary).  Tiger (EN), Asiatic Black Bear (VU) and Leopard (VU) are observed in the forests of the project site (interview with local people).  No endangered species of Fish have been confirmed near the outlet of the powerhouse (interview with local people).

Resettlement /  N/A Compensatory assets Historical / Cultural  N/A Heritage Other  The three components of the Dam, Waterway and Powerhouse are located in a National Park.

 Punakha Dzongkhag is very strict in the preservation of the natural environment and cultural sites. Development work in the buffer zone of cultural sites is difficult in Punakha. Consideration for the landscape during construction work and the operation period is essential. Development plans at the ministry level are to be discussed with the Dzongkhag prior to the final decision.  Boundaries of government land and royal family's land remain unclear in Punakha.  Dzongkhag Admin Office reminded us that it is hard to ensure the availability of vacant land. Amendment of land use requires not only the consent of the Ministry of Human Settlement but that of the royal family.  Water sources are drying up year by year, and there are water shortages at small tributaries. On the other hand, the people suffer from floods during the summer time when they have heavy rains (there was a massive flood in 1994). There is an early warning system for GLOF and disaster maps are developed by MCHM.

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Figure A 1-13 Plot Plan (P-15)

Figure A 1-14 Longitudinal Profile (P-15)

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1.8 P-17: Tseykha

Project Name P-17: Tseykha Date 10/12/2018 Basin Punatsangchhu Tributary Phochhu Dam (Weir) Latitude: 27° 40' 49.90" N Longitude: 89° 56' 7.10" E Powerhouse Latitude: 27° 36' 20.68" N Longitude: 89° 52' 40.77" E

Type ROR+Pond RBL at Dam EL 1,380m Installed 170 MW Dam Height 49 (29) m Capacity Primary Data Salient Max. Discharge 162.8 m3/s Crest Length 90 m General Features Features Effective Head 120.9 m Waterway Length 9,980 m Live Storage Catchment Area 2,205 km2 0.4 MCM Capacity Elongation from Dam site: 3 km Existing Road Powerhouse Site: 0 km Access

River Flow Rate 100 – 120 m3/s (Eye Measurement)

Hydrology Sediment 0.1 – 0.5 m (Gravel - Boulder) General Geology Geofacies (compiled by Long et al., 2011) are as follows: 【Dam ~ Powerhouse】 Subsurface geology of the project area belongs to the Upper metasedimentary unit (GHlmu) in the Structurally-lower Greater Himalayan section in the Greater Himalayan Zone of the Neoproterozoic-Ordovician [?] period. Variable metamorphic grades; dominantly amphibolite facies (Gansser, 1983), partial melt- and often kyanite-, sillimanite-, or staurolite-bearing paragneiss, schist, and quartzite in east (Grujic et al., 2002) and near base in west-central Bhutan, and melt-free, dominantly upper greenschist- facies (Gansser, 1983) quartzite and biotite-muscovite-garnet schist in central Bhutan (Long and McQuarrie, 2010).

【Waterway ~ Powerhouse】

Subsurface geology of the project area falls in the Orthogneiss unit (GHlo) from the Cambrian to the Ordovician Period in the Structurally- lower Greater Himalayan section of the Greater Himalayan Zone in Neoproterozoic-Ordovician [?] period. Cliff-forming, massive-weathering, granite-composition orthogneiss; generally, exhibits leucosomes and abundant feldspar augen. Paragneiss, schist, and quartzite intervals locally split out. Interpreted as deformed Cambrian-Ordovician granite plutons that intruded Greater Himalayan Geography / Geology

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sedimentary protoliths thickens toward eastern Bhutan.

 No geographic problems which imply a landslide and/or mass rock creeping were observed during the site reconnaissance.  The topography from the Dam site to Powerhouse site forms a gentle uniform slope of 30 - 40°, and there are steep cliffs in some places.  Clear lineaments are not observed around the Powerhouse site.  The geology observed at the cut slope of the road is Gneiss and Schist.

Dam / Intake Observed with drone  The terrain on the right bank forms a steep cliff. Since the slopes on the left banks are covered by vegetation, the geological conditions are unknown (Photos 1, 2, 3, 4).  The geology around the Dam site is assumed to be Gneiss and Schist, judging from the surrounding outcrops (Photo 5).  The overall geological structure is EW~NW-SEN strike and it is inclined 10 - 20° to the north, judging from the surrounding outcrops.  Sediment volume is assumed to be small in general (Photo 6). Construction materials have not yet been observed.

Waterway  The topography along Phochhu is, in general, inclined 30 - 40°.  The geology around the Dam site is assumed to be Gneiss and Schist, judging from the outcrops along the road.  RMR evaluation point marks 58 and the rock classification is mainly Class-III.

Powerhouse  The topography of the Powerhouse site is a talus slope which is uniformly inclined 20 - 30° to the riverbed (Photos 7, 8, 9).  The geology is talus cone deposits and terrace deposits (Photo 10). The bed rock is assumed to be mainly Gneiss, judging from a moving rock (Photo 11).

Natural Park / Protected  Part of the Dam and intake (right bank of river) is located on the Area border of a Protected Area (Jigme Dorji National Park).

Prosperous fauna / flora  The north part of the Dam site (within the National Park) is covered with primeval forest of Chir pine. However, the southern part of the

Dam site (not in the National Park) is covered with warm broad- leaved forest composed of Bischofia javanica and Castanopsis indica.  The Waterway (underground), and Powerhouse site are covered with scattered Chir pine forest composed of Pinus roxburghii and Cycas pectinate.  Tiger (EN), Asiatic Black Bear (VU) and Leopard (VU) are observed in the forests of the project site (interview with local people).  No endangered species of Fish have been confirmed near the outlet of the powerhouse (interview with local people).

Natural / Social Environment Resettlement /  Livelihood activities in the area surrounding the PH site may be Compensatory assets affected during the construction phase if it is built on the surface. Historical / Cultural  N/A Heritage Other  There is a habitat of White-bellied Heron which plays an important

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role in providing a feeding and nesting place between the Dam site and the outlet site from the powerhouse.  There is a private house and rice field near the planned powerhouse. The Gup of Dzomi Gewog mentioned that local people will show a positive attitude towards the project implementation although their livelihood activities will be affected to some extent.  According to the Punakha Dzongkhag Administration Office, a sacred mountain in the shape of an elephant’s nose between Phochhu and Mochhu will soon be designated as a heritage site by the Department of Culture (DOC). This is on the opposite side of Phochhu from the powerhouse site. All development acts on the mountain are prohibited. DOC and the Dzongkhag Administration adopt a cautious attitude, whereas the Gup of Dzomi Gewog mentioned that the project will do no harm as the planned location of the PH is on the other side of the river, and transmission lines can avoid the sacred site by rerouting.  Punakha Dzongkhag is very strict in the preservation of the natural environment and cultural sites. For instance, a buffer zone is created within an area of 500 m from the Dzong in radius. Development work in the buffer zones of cultural sites is difficult in Punakha. Consideration for the landscape during construction work and the operation period is essential. Development plans at the ministry level are to be discussed with the Dzongkhag prior to the final decision.  Boundaries of government land and royal family's land remain unclear in Punakha.  Dzongkhag Admin Office reminded us that it is hard to ensure the availability of vacant land. Amendment of land use requires the consent of not only the Ministry of Human Settlement but also the royal family.  Water sources are drying up year by year, and there are water shortages at small tributaries. On the other hand, the people suffer from floods during the summer time when they have heavy rains (there was a massive flood in 1994). There is an early warning system for GLOF and disaster maps are developed by MCHM.

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Right bank

Left bank

Photo 1 Dam Site

Right bank Left bank

Photo 2 Upper Stream of Dam Site

Right bank

Dam

Left bank

Photo 3 Right Bank of Dam Photo 4 Outcrop on Right Bank of Dam (Gneiss?)

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Photo 5 Right Bank of Dam Photo 6 Riverbed near Dam Site

Photo 7 Powerhouse Site

PH

Photo 8 Riverbed near Powerhouse Site Photo 9 Powerhouse Site (Open Type)

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Photo 10 Terrace Deposits around Powerhouse Photo 11 Moving rock around Powerhouse (Granite) (Gneiss)

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Figure A 1-15 Plot Plan (P-17)

GHlmu GHlo

Figure A 1-16 Longitudinal Profile (P-17)

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1.9 P-26: Thasa

Project Name P-26: Thasa Date 14/11/2018 Basin Punatsangchhu Tributary Sankoshchhu Dam (Weir) Latitude: 27° 12' 28.31" N Longitude: 90° 4' 9.15" E

Powerhouse Latitude: 27° 5' 55.41" N Longitude: 90° 4' 8.53" E Type ROR RBL at Dam EL 460 m Installed Dam/Weir 706 MW 108 (23) m Capacity Height

Primary Data Max. 489.3m3/s Salient Crest Length 350 m General Discharge Features Features Effective Waterway 167.4.0 m 10,579 m Head Length Catchment Live Storage 7,040 km2 39.5 MCM Area Capacity Elongation from Dam site: Along with National highway Existing Road Powerhouse Site: 1 bridge and 0.5 km Access General Geology Geofacies (compiled by Long et al., 2011) are as follows: The subsurface geology of the project area belongs to the Upper metasedimentary unit in the Structurally-lower Greater Himalayan section in the Greater Himalayan Zone of the Neoproterozoic-Ordovician [?] period. Variable metamorphic grades; dominantly amphibolite facies (Gansser, 1983), partial melt- and often kyanite-, sillimanite-, or staurolite-bearing paragneiss, schist, and quartzite in east (Grujic et al., 2002) and near base in west-central Bhutan, and melt-free, dominantly upper greenschist-facies (Gansser, 1983) quartzite and biotite-muscovite-garnet schist in central Bhutan (Long and McQuarrie, 2010).

Leucogranite of the Miocene period, which belongs to the Structurally- higher Greater Himalayan section, intrudes to the above-mentioned older rocks crossing the Punatsangchhu. Syncline axis passes through on the one third reach from the intake of the waterway almost perpendicular to the waterway route.

Dam / Intake  Since the original dam site was located in the core zone of Jigme Singye Geography / Geology Wangchuck National Park and its connected corridor, the dam site was shifted approximately 3km downstream. Though the riverbed elevation became about 20m lower, water flow from Harachhu can be utilized.  Topography of the dam site is quite narrow and steep at about 60-70 degrees.  Geology of the dam site is quartzite dominant, for which the strike/dip is N70E/45S.  Concrete gravity type dam is preferable because of the morphologic and geologic features.  Construction material for the dam should make the most of the quarry site which was used for the previous Punatsangchhu I project.

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Waterway  One of the advantages of shifting the dam site downstream is that the waterway route can be planned to run on the left bank of the river and the waterway length can be shortened.  Two lineaments are observed on 1/3 and 2/3 of the waterway route on the Google Earth image but they could not be observed clearly.  Bedded quartzite is observed on both right and left banks along the Punatsangchhu, for which the weathering grade is Moderately Weathered (MW) on the surface of the cliff. However, it is presumed that the weathering grade on some parts of the headrace tunnel is Slightly Weathered (SW).  The headrace tunnel route may mainly belong to Class-III rock, for which the RMR value is estimated to be 57.

Powerhouse  It is recommended that an open-air type powerhouse is built on the alluvial plain on the left riverbank of Punatsangchhu.  Since the height of the alluvial plain from the present riverbed is less than 10m, a bank wall will be required to protect the powerhouse from floods during the construction and operation periods.

Natural Park /  The intake is on the border of a Biological Corridor (JDNP-JSWNP) and Protected Area Jigme Singye Wangchuck National Park. The national park side is the Core Zone.  Part of the waterway (underground) is within the corridor.

Prosperous fauna /  Chir Pine Forest covers the project area. flora  White-bellied Heron (CR) and Asian Small-clawed Otter (VU) are observed in Punatsangchhu.  Along the road of the right bank, just downstream of the dam site, a rare plant, Pentasacme pulcherrima, is observed. This plant is found in only two places (including this site) in Bhutan.

Resettlement / According to the GIS data from NLC and an interview with Athang Gewog, Compensatory assets  No resettlement is required.  No private land acquisition is required.  In the case of the revised dam location, reconstruction of public infrastructure may be necessary, such as: - Two motorable bridges and 1 suspension foot bridge - Taksha Park Range Office of Jigme Singye Wangchuck National Park (including staff quarters) - Golden Mahseer Hatchery for protection of the endangered migratory fish in Punatsangchu river (including office and staff quarters)

Natural / Social Environment Historical / Cultural  According to the GIS data from NLC and an interview with Athang Heritage Gewog and village representatives (Tshopas), no cultural heritage sites are located in the dam site, reservoir area or powerhouse site.

Other  Athang gewog, the project site location, is one of the poorest gewogs in Wangduephodrang Dzongkhag.  There is an indigenous community called "Rukha", which consists of 11 villages of two chiwogs in Wangduephodrang Dzongkhag and 1 village under Tsirang Dzongkhag, along with Harachhu in a stretch of approx. 20km upstream from the junction with Puntsangchu. They can fish officially in Harachhu, from this junction to above Dayul and Chinading Villages. Fishing activities are one of the primary sources of cash income for the community.

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Other (Special Note)  Accessibility of Rukha community residences is important, and key for their livelihood. Bridges which will be submerged in the revised dam area are the only access points to paved roads for the Rukha Community.  Careful investigation into the impact of the revised reservoir on the fish population and migration should be carried out to understand the potential impact of the project on the fishing activities of the Rukha Community.

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Photo 1 Left Bank of Dam Site Photo 2 Right Bank of Dam Site

Photo 3 Downstream View of Dam Site Photo 4 Candidate for Quarry which was used for the previous project

Photo 5 Bedded Quartzite near Powerhouse Site Photo 6 Surge Tank and Powerhouse Site

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Figure A 1-17 Plot Plan (P-26)

Figure A 1-18 Longitudinal Profile (P-26)

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1.10 P-28: Kago-1

Project Name P-28: Kago-1 Date - Basin Punatsangchhu Tributary Kisonachhu Dam (Weir) Latitude: 27°20'32.23"N Longitude: 90° 8'59.88"E Powerhouse Latitude: 27°19'58.42"N Longitude: 90° 8'41.54"E RBL at Type ROR EL 2,340 m Dam Installed Dam/Weir 102 MW 5 m Capacity Height

Primary Data Max. Crest 17.2 m3/s Salient 30 m Discharge Length General Features Effective Waterway Features 688.2 m 2,056 m Head Length Live Catchment 250 km2 Storage MCM Area Capacity Elongation from Existing The Powerhouse site is located 0.6km upstream of the intake of the Road Bartsha Site. The intake site of Kago-1 is located a further 1.8km upstream. In total,

Access 6.4km of new access road is to be constructed, and 22km of the existing road should be improved. General Geology Geofacies (compiled by Long et al., 2011) are as follows: The subsurface geology of the project area falls in the Upper metasedimentary unit in the Structurally-lower Greater Himalayan section in the Greater Himalayan Zone (Ghlmu) of the Neoproterozoic-Ordovician [?] period. Variable metamorphic grades; dominantly amphibolite facies (Gansser, 1983), partial melt and often kyanite-, sillimanite-, or staurolite-bearing paragneiss, schist, and quartzite in the east (Grujic et al., 2002) and near the base in west-central Bhutan, and melt-free,

dominantly upper greenschist-facies (Gansser, 1983) quartzite and biotite-muscovite-garnet schist in central Bhutan (Long and McQuarrie, 2010).

 There are some unknowable geographic concerns. The first is that there are plenty of N-S trend fissures, and the second is the form of the tributary which flows on the mountain-side observed in the Google Earth image. It indicates the possibility of the existence of Geography / Geology some soluble rocks, such as limestone or dolostone.  Since the existing geological map referred to has limitations in accuracy in some detailed parts, detailed geological investigation is required to conduct a review of geological mapping for the project implementation.

Weir / Intake  It seems that there are no particular issues with small-scale weir construction.  Since there are plenty of fissures with a N-S trend, there might be Waterway

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Powerhouse similar systematic fissures along the headrace tunnel route. This might make the headrace tunnel construction difficult, since such systematic fissures sometimes lead large volumes of water leakage into the tunnel during excavation.  Bedrock of the underground powerhouse site may also have a similar issue to the headrace tunnel route concerning water leakage. Natural Park / Protected  The river is the border of a Biological Corridor (North) and Jigme Area Singye Wangchuck National Park. The national park side is the Core Zone. All facilities of the project fall into either the corridor or the national park.

Prosperous fauna / flora  Cool broad-leaved forest covers the project area.  Endangered species (categorized by IUCN) are likely to be present in the project area.  According to the villagers of Lophikha, the village close to the project site, White-bellied Heron (CR) is regularly observed in the pond in the village (interview during the survey).

Resettlement / According to the GIS data from NLC and an interview with Athang Gewog Compensatory assets and the Kago-Lomtshokha chiwog representative at the dam site and the powerhouse,  No resettlement is required.  No private land acquisition is required.

Historical / Cultural  According to the GIS data from NLC and an interview with Athang Heritage Gewog and the Kago-Lomtshokha chiwog representative, no cultural heritage sites are present at the project site.

Other Natural / Social Environment  Athang gewog, the project site location, is one of the poorest gewogs in Wangduephodrang Dzongkhag.  No indigenous communities are near the project site.

 Tourism development with eco-trails is being planned under the budget of the 12th Five Year Plan (2018-2023).  Expansion of Horticulture Development Program (fruit trees such as Mango, Guava, Orange, Walnut, etc.) is being undertaken using the budget of the Gewog Development Fund, and financial support from the Ministry of Agriculture and Forests and the International Fund for Agricultural Development (IFAD). Potential for increased sales of local products can be expected due to road improvements in this area via the project.

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Figure A 1-19 Plot Plan (P-28)

Figure A 1-20 Longitudinal Profile (P-28)

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1.11 P-29: Kago

15/11/2018 Project Name P-29: Kago Date 16/11/2018 Morichhu Basin Punatsangchhu Tributary Porichhu Latitude: 27° 19' 22.28" N Longitude: 90° 8' 29.50" E Dam (Weir) 27° 20' 11.69" N 90° 5' 27.62" E

Powerhouse Latitude: 27°18' 5.60" N Longitude: 90° 6' 18.85" E

Type ROR RBL at Dam EL 1,480 m Installed Dam/Weir 5 m 58 MW

Primary Data Capacity Height 5 m Max. 40 m 26.0 m3/s Salient Crest Length General Discharge Features 40 m Features Effective Waterway 250.4 m 5,900 m Head Length Catchment Live Storage 377 km2 MCM Area Capacity Elongation from Dam site: 4 km to No. 1 Weir site and 5 km to No. 2 Weir site Existing Road (improvement of 22 km - long existing road is required) Access Powerhouse Site: 1 bridge and 0.5 km General Geology Geofacies (compiled by Long et al., 2011) are as follows: The subsurface geology of the project area belongs to the Upper metasedimentary unit in the Structurally-lower Greater Himalayan section in the Greater Himalayan Zone of the Neoproterozoic-Ordovician [?] period. Variable metamorphic grades; dominantly amphibolite facies (Gansser, 1983), partial melt- and often kyanite-, sillimanite-, or staurolite-bearing paragneiss, schist, and quartzite in the east (Grujic et al., 2002) and near the base in west- central Bhutan, and melt-free, dominantly upper greenschist-facies (Gansser, 1983) quartzite and biotite-muscovite-garnet schist in central Bhutan (Long and McQuarrie, 2010).

Leucogranite of the Miocene period belonging to the Structurally-higher Greater Himalayan section intrudes into the above-mentioned older rocks near the Punatsangchhu.

 Leucogranite is widely distributed along the existing local forest road from the weir site to the bridge crossing the Punatsangchhu, while the geology map (produced by Long et al., 2011) shows that the distribution area is limited to

Geography / Geology near the Punatsangchhu. Furthermore, the rock is distributed on the right bank of the Morichhu in the eastern part of the headrace tunnel, too.

Weir / Intake  No. 1 Weir is located on the Morichhu, and No. 2 Weir is located on the Porichhu. Since a tributary of the Morichhu had frequent floods, the No. 1 weir site location was selected to be just upstream of the confluence with the tributary.  Since the intake discharges designed for both weirs are less than 25m3/s, a Trench type weir is recommended to be built on the alluvial flood plains, where there are huge boulders and gravel.

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Waterway  Leucogranite outcrops are observed as massive rocks with Slightly Weathered (SW) or Moderately Weathered (MW) conditions along the Morichhu and steep cliffs on the left bank of the Porichhu, close to the powerhouse site.  It is presumed that the whole waterway route will run in the Leucogranite zone. The rock classification along the headrace tunnel is estimated to be mainly Class-II with an RMR value of 74.  Since N-S trend joints are highly dominant on the Google Earth Image, some of them may appear on the E-W direction waterway. Furthermore, there are E-W trend lineaments across the waterway route.  The two headraces from the Morichhu and Porichhu are joined at the center of the ridge, and one headrace conveys the water to the powerhouse.  Since the mountain body of the waterway route is relatively gentle, a surface- type penstock is recommended.

Powerhouse  It is recommended to build the surface type powerhouse on the alluvial plain at the confluence of the Morichhu and Porichhu, although no outcrops are observed.  Since the height of the alluvial plain is less than 10m from the riverbed, training walls are required to protect it from floods during construction and operation.

Natural Park /  Two intakes are planned for the project. One of them, the eastern intake Protected Area (Bartsha (1)), is located on the border of Jigme Singye Wangchuck National Park. The national park side seems to be the Core Zone, but this needs to be verified.

Prosperous fauna /  Warm broad-leaved forest covers the project area. 

flora Foot prints of Leopard were observed by a guide from the local village during the field survey on 15 November 2018. Leopard is categorized as Vulnerable by the IUCN. Feces of otter (species unknown) were observed by the local expert during the survey. The otter may be the Asian Small-clawed Otter, which is categorized as Vulnerable.  According to the villagers of Lophokha, the village close to the project site, White-bellied Heron (CR) is regularly observed in the pond in the village (interview during the survey).

Resettlement / According to the GIS data from NLC and interview with Athang Gewog, Compensatory assets  No resettlement is required. Natural / Social Environment  No private land acquisition is required.

Historical / Cultural  According to the GIS data from NLC and interview with Athang Gewog and Heritage village representatives (Tshopas), no cultural heritage is affected. There is a lake, “Athang (Adha) Tsho”, in the south of Lophokha Village which local people consider a holy site. The project does not affect this lake.

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Other  Athang gewog, the project site location, is one of the poorest gewogs in Wangduephodrang Dzongkhag.  No indigenous communities are near the project site.

 Tourism development with eco-trails is being planned under the budget of the 12th Five Year Plan (2018-2023).  Expansion of the Horticulture Development Program (fruit trees such as Mangoes, Guava, Oranges, Walnut, etc.) is being undertaken using the budget of the Gewog Development Fund and financial support from the Ministry of Agriculture and Forests and the International Fund for Agricultural Development (IFAD). Potential for increased sales of local products can be expected due to road improvement in this area for the project.

←Weir Site

Photo 1 Weir Site Photo 2 Riverbed Condition at Weir Site

Photo 3 Outcrop of Leucogranite along Porichhu Photo 4 Rock exposed near Powerhouse Site

Photo 5 Surge Tank & Powerhouse Site Photo 6 Surge Tank & Powerhouse Site

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Figure A 1-21 Plot Plan (P-29)

Figure A 1-22 Longitudinal Profile (P-29)

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1.12 P-29R: Kago_Rev

Project P-29R: Kago_Rev Date 19/01/2019 Name Basin Punatsangchhu Tributary Morichhu Dam (Weir) Latitude: 27° 19' 33.45" N Longitude: 90° 8' 44.18" E Powerhouse Latitude: 27° 18' 5.60" N Longitude: 90° 6' 18.85" E Type ROR RBL at Dam EL 1,585 m

Installed Dam/Weir 58 MW 5 m Capacity Height Primary Data Max. 17.9 m3/s Salient Crest Length 30 m General Discharge Features Features Effective Waterway 376.7 m 6,124 m Head Length Catchment Live Storage 260 km2 MCM Area Capacity

Elongation from Intake Weir Site: 5 km Existing Road (improvement of 22km-long existing road is required)

Access Powerhouse Site: 1 bridge and 0.5km

River Flow Rate Around 4.0 m3/s (Eye Measurement)

Hydrology Sediment 0.5 – 5.0 m (Boulders) General Geology Geofacies (compiled by Long et al., 2011) are as follows: The subsurface geology of the project area belongs to the Upper metasedimentary unit in the Structurally-lower Greater Himalayan section in the Greater Himalayan Zone of the Neoproterozoic-Ordovician [?] period. Variable metamorphic grades; dominantly amphibolite facies (Gansser, 1983),

partial melt- and often kyanite-, sillimanite-, or staurolite-bearing paragneiss, schist, and quartzite in the east (Grujic et al., 2002) and near the base in west- central Bhutan, and melt-free, dominantly upper greenschist-facies (Gansser, 1983) quartzite and biotite-muscovite-garnet schist in central Bhutan (Long and McQuarrie, 2010). Leucogranite of the Miocene period belonging to the Structurally-higher Greater Himalayan section intrudes into the above-mentioned older rocks near the Punatsangchhu. Geography / Geology  Leucogranite is widely distributed along the existing local forest road from the weir site to the bridge crossing the Punatsangchhu while the geology map (produced by Long et al., 2011) shows that the distribution area is limited near the Punatsangchhu. Furthermore, the rock is distributed on the right bank of the Morichhu, on the eastern part of the waterway, too (Photos 2 and 3).

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Weir / Intake  Diversion of the tributary is abandoned and the intake site of the main river is sifted to the upmost stream, outside of the protected area on the right bank.  The weir is located on the Morichhu between the outlet of the Kago-1 scheme and the No. 1 Weir of the original Bartsha scheme (Photo 1).  Since the max. discharge is less than 25m3/s, a trench weir is adopted.  The location of the intake is selected to be on the right bank of the weir. The rock conditions of the intake site could not be verified because the location is covered by high vegetation.

Waterway  Massive Leucogranite is observed, of Fresh to Slightly Weathered (SW) conditions on the outcrop beside the Morichhu and Moderately Weathered (MW) conditions on the steep cliff on the left bank of the Porichhu, close to the powerhouse site (Photo 3).  It is presumed that the whole waterway route passes through the Leucogranite zone. The rock classification along the headrace tunnel is assumed to be mainly Class-II rock, whose RMR value is estimated to be 74 (engineer’s intuition).  E-W trend lineaments are visible on the Google Earth image.  Since the terrain of the Penstock route is relatively gentle, an open-air type is recommended (Photo 4).

Powerhouse  It is recommended to employ an open-air type powerhouse on the alluvial plain at the confluence of the Morichhu and Porichhu.  Since the elevation of the alluvial plain is less than 5m higher than the riverbed, training walls need to be constructed in order to protect the powerhouse from flooding during the construction and operation stages (Photo 5).

Natural Park /  Weir is located on the border of Jigme Singye Wangchuck National Park. The Protected Area national park side seems to be the Core Zone, but this needs to be verified.

Prosperous fauna /  Warm broad-leaved forest covers the project area. flora  Foot prints of Leopard were observed by a guide from the local village during

the field survey on 15 November 2018. Leopard is categorized as Vulnerable by the IUCN. Feces of otter (species unknown) were observed by the local expert during the survey. The otter may be the Asian Small-clawed Otter, which is categorized as Vulnerable.  According to the villagers of Lophokha, the village close to the project site, White-bellied Heron (CR) is regularly observed in the pond in the village (interview during the survey).

Resettlement / According to the GIS data from NLC and interview with Athang Gewog, Compensatory  No resettlement is required.  Natural / Social Environment assets No private land acquisition is required.

Historical /  According to the GIS data from NLC and interview with Athang Gewog and Cultural Heritage village representatives (Tshopas), no cultural heritage is affected. There is a lake, “Athang (Adha) Tsho”, in the south of Lophokha Village which local people consider a holy site. The project does not affect this lake.

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Other  Athang gewog, the project site location, is one of the poorest gewogs in Wangduephodrang Dzongkhag.  No indigenous communities are near the project site.  Positive impacts on access to education and health facilities can be expected due to improvement of the road via the project, since the villages near the dam and powerhouse area are connected only by farm road from the Athang Gewog (approx. 22 km). A few houses are not connected by any type of road.

 Tourism development with eco-trails is being planned under the budget of the 12th Five Year Plan (2018-2023).  Expansion of the Horticulture Development Program (fruit trees such as Mangoes, Guava, Oranges, Walnut, etc.) is being undertaken using the budget of the Gewog Development Fund and financial support from the Ministry of Agriculture and Forests and the International Fund for Agricultural Development (IFAD). Potential for increased sales of local products can be expected due to road improvement in this area for the project.

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Photo 1 Weir Site

Photo 2 Outcrop of Leucogranite along Morichhu Photo 3 Rock exposed on the left bank of Porichhu near Powerhouse Morichhu

Porichhu

Photo 4 Surge Tank Location Photo 5 Powerhouse & Switch Yard Site

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Figure A 1-23 Plot Plan (P-29R)

Figure A 1-24 Longitudinal Profile (P-29R)

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1.13 P-30: Pinsa

14-16/11/2018 Project Name P-30: Pinsa_Rev Date 20/01/2019 Kisonachhu Basin Punatsangchhu Tributary （Morichhu & Porichhu） Latitude: 27° 17' 42.22" N Longitude: 90° 6'11.61"E Dam (Weir) Latitude: 27° 17' 42.10" N Longitude: 90° 6' 8.18" E

Powerhouse Latitude: 27° 14' 31.89" N Longitude: 90° 3' 27.92" E

Type ROR RBL at Dam EL 1,170 m Installed Dam/Weir 5 m 153 MW Primary Data Capacity Height 5 m 3 Max. 20.7 m /s Salient 40 m 3 Crest Length General Discharge 8.7 m /s Features 30 m Features Effective Waterway 604.8 m 7,634 m Head Length Catchment 301 km2 Live Storage MCM Area 126 km2 Capacity Elongation from Dam site: 0 km (improvement of 22km-long existing road is required) Existing Road Powerhouse Site: 1 bridge and 0.5km (improvement of 3km-long existing road is

Access required)

River Flow Rate About 5 m3/s (Morichhu) (Eye Measurement) About 2.5 m3/s (Porichhu)

Hydrology Sediment 1.0 – 5.0 m (Boulder) General Geology Geofacies (compiled by Long et al., 2011) are as follows: The subsurface geology of the project area belongs to the Upper metasedimentary unit in the Structurally-lower Greater Himalayan section in the Greater Himalayan Zone of the Neoproterozoic-Ordovician [?] period. Variable metamorphic grades; dominantly amphibolite facies (Gansser, 1983), partial melt- and often kyanite-, sillimanite-, or staurolite-bearing paragneiss, schist, and quartzite in the east (Grujic et al., 2002) and near the base in west- central Bhutan, and melt-free, dominantly upper greenschist-facies (Gansser, 1983) quartzite and biotite-muscovite-garnet schist in central Bhutan (Long and McQuarrie, 2010).

 Leucogranite of the Miocene period belonging to the Structurally-higher Greater Himalayan section intrudes into the above-mentioned older rocks near the Punatsangchhu.  Leucogranite is widely distributed along the existing local forest road from the weir site to the bridge crossing the Punatsangchhu.

Geography / Geology Dam / Intake  The locations of the weirs are selected to be just upstream of the confluence of Morichhu and Porichhu, where the terrain forms a relatively gentle river slope and wide river (Photos 1 and 2).  Since no bedrock is observed around the weir site, a trench weir is recommended to be built on a wide alluvial flood plain where there are many huge (3m to 10m) boulders (Photo 3).  The location of the desilting basin is selected to be on the right bank.  In consideration of the possibility of frequent floods, protection walls should be installed to protect the intake gate and the desilting basin from attack by huge boulders associated with floods.

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Waterway  Leucogranite is observed as massive rocks with slightly weathered (SW) or moderately weathered (MW) conditions on most outcrops (Photo 4).  It is presumed that the whole waterway route passes through the Leucogranite zone. The rock classification along the headrace tunnel is assumed to be mainly Class-II rock, whose RMR value is estimated as 74 (engineer’s intuition) (Photo 5).  A ground surface type penstock is advantageous from the economic efficiency aspect. However, at this site, since there is swamp topography, which is inferred to be formed along the geological layer border (by the intrusion of granite in the bedrock) along the ridge, the alignment of the penstock is changed to run along a ridge of gneiss on the downstream side. Even in the case of using an embedded type for the penstock, its alignment is changed so as to run in the gneiss rockmass (Photos 7 and 8).

Powerhouse  It is recommended that a ground surface type powerhouse be installed on the alluvial plain on the left riverbank of Punatsangchhu.  Since the alluvial plain is only approximately 10m higher than the riverbed, protection walls are required to provide protection from floods during the construction and operation stages.

Natural Park /  The intake is located on the border of Jigme Singye Wangchuck National Park. Protected Area The national park side is a Multiple-use Zone.

Prosperous fauna /  Warm broad-leaved forest covers the intake and waterway area. Chir Pine flora Forest covers the power plant area.

 According to the villagers of Lophokha, the village close to the intake site, White-bellied Heron (CR) is regularly observed in the pond in the village (interview during the survey).  The power plant is located on the left bank of Punatsangchhu. White-bellied Heron and Asian Small-clawed Otter (VU) are observed in Punatsangchhu.

Resettlement / According to the GIS data from NLC and interview with Athang Gewog and the Compensatory assets Lopokha – Phakthakha chiwog representative (Tshopas), by the dam site and the powerhouse,  No resettlement is required.

Natural / Social Environment  No private land acquisition is required.

Historical / Cultural  According to the GIS data from NLC and interview with Athang Gewog and Heritage Lopokha– Phakthakha chiwog representative, no cultural heritage is directly affected at the project site.

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Other  Athang gewog, the project site location, is one of the poorest gewogs in Wangduephodrang Dzongkhag.  The project is located in areas which are uninhabited and has been named Pinsa based on the name of the village opposite the powerhouse across the Punatsangchhu.  Positive impacts on access to education and health facilities can be expected due to improvement of the road via the project since the villages near the dam and powerhouse area are connected only by farm road from the Athang Gewog (approx. 22 km). A few houses are not connected by any type of road.

 Tourism development with eco-trails is being planned under the budget of the 12th Five Year Plan (2018-2023).  Expansion of the Horticulture Development Program (fruit trees such as Mangoes, Guava, Oranges, Walnut, etc.) is being undertaken using the budget of the Gewog Development Fund and financial support from the Ministry of Agriculture and Forests and the International Fund for Agricultural Development (IFAD).

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Photo 1 Weir Site (Porichhu) Photo 2 Weir Site (Morichhu)

Photo 3 Just Upstream of Confluence Point Photo 4 Leucogranite distributed along Local Road

Photo 5 Geological boundary of Quartzite and Photo 6 Powerhouse Site Leucogranite

Powerhouse and Switchyard

Photo 7 Surge Tank and Penstock Photo 8 Penstock Route

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Figure A 1-25 Plot Plan (P-30)

Figure A 1-26 Longitudinal Profile (P-30)

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1.14 P-34: Darachhu

Project Name P-34: Darachhu Date 15/11/2018 Basin Punatsangchhu Tributary Darachhu Dam (Weir) Latitude: 27° 6' 3.32" N Longitude: 89° 47' 2.28" E

Powerhouse Latitude: 27° 3' 34.91" N Longitude: 89° 51' 57.44" E Type ROR RBL at Dam EL 1,640 m Installed Dam/Weir 61 MW 5 m Capacity Height

Primary Data Max. 15.3 m3/s Salient Crest Length 30 m General Discharge Features Features Effective Waterway 460.4 m 10,625 m Head Length Catchment Live Storage 220 km2 MCM Area Capacity

Elongation from Dam site: 15 km from the Powerhouse Site ess Acc Existing Road Powerhouse Site: 1 bridge and 3km River Flow Rate N.A.

(Eyegy Measurement)

Hydrolo Sediment N.A. General Geology Geofacies (compiled by Long et al., 2011) are as follows: The subsurface geology of the project area belongs to the Upper metasedimentary unit in the Structurally-lower Greater Himalayan section in the Greater Himalayan Zone of the Neoproterozoic-Ordovician [?] period. Variable metamorphic grades; dominantly amphibolite facies (Gansser, 1983), partial melt- and often kyanite-, sillimanite-, or staurolite-bearing paragneiss, schist, and quartzite in the east (Grujic et al., 2002) and near the base in west-central Bhutan, and melt-free, dominantly upper greenschist- facies (Gansser, 1983) quartzite and biotite-muscovite-garnet schist in

central Bhutan (Long and McQuarrie, 2010).

 Schist and Gneiss are distributed downstream of the Powerhouse site along Dagachhu. In consideration of Long’s geological map, the same geology is assumed to be distributed across the whole project area.  In Google Earth images, no large-scale collapsed land or clear lineaments are visible across the whole project area.

Geography / Geology Weir / Intake  In consideration of Long’s geological map, the geology around the Dam site, as well as that downstream of the Powerhouse site, is assumed to be Gneiss and Schist. The overall geological structure is assumed to be NW- SE strike and to be inclined gently to the north.

Waterway  Although the geology along the waterway route was not observed, if it has similar characteristics to that downstream of the Powerhouse site it is assumed that the RMR evaluation point marks 58 and the rock classification is mainly Class-III.

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Powerhouse Observed with drone  Since the slope that the Powerhouse is planned to be located on is uniformly inclined at around 40° and no landslides or mass rock creeping have been observed, the slope seems to be stable (Photos 1 and 2).  Degree of weathering or loosening is assumed to be low, judging from the outcrops downstream of the Powerhouse site.  The geology around the Powerhouse site is assumed to be Gneiss and Schist, judging from the outcrops downstream of the Powerhouse site along Dagachhu. The overall geological structure is NW-SE strike and it is inclined 5 - 20° to the north (Photo 3).

Natural Park /  The project area is outside the protected area. However, the waterway, Protected Area surge-tank and powerhouse are located in Heritage Forest, for which development is strictly regulated by the Forest and Nature Conservation Act 1995. Prosperous fauna /  The weir site is covered by pure cool broad-leaved trees (interview with flora forest office), but the sites for the waterway, surge-tank and powerhouse are covered with mixed forest composed of cool broad-leaved such as Java Ceder, Parasol leaf tree and conifer of chir pine forest of Pinus roxburghii.  The right flank of the weir is contiguous with Heritage Forest, but it will not cause an impact on the trees of the Heritage Forest as its area is vertical rock with no growing trees.  There are some small mountain flows downstream, but flowing is not anticipated during any time of the year.  In terms of endangered species designated by the IUCN, according to an interview with the forest office, Cycas Pectinata (VU), Rufous-necked Hornbill (VU) White-bellied Heron (CR), and Tiger (EN) have been

confirmed at the project site.

Resettlement /  N/A Compensatory assets Historical / Cultural  N/A Heritage Other  People see the project as one of the most effective elements for fast socio- economic development of the gewog. Therefore, the people would welcome the project. Natural / Social Environment  Poverty rates are better (around 20%) than the average of the whole Dzongkhag. They requested us to widen and improve the existing road in the Gewogs.  There is no road to the site at present. Better road access and network will help promote market access and tourism (a trekking course is under development).

 Dagana Dzongkhag Administration Office and Gewog Offices (Tseza and Kana) request that no impacts such as noise or vibrations be caused to the Dzong in any case.

 There is 1.5 acres of barren land owned by 4 households on the surface of the PH site. If the PH is constructed on the surface, no resettlement or asset loss is anticipated as their living places are located away from it.

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PS

Dagachhu

Photo 1 Powerhouse Site Photo 2 Powerhouse Site

Photo 3 Outcrop downstream of Powerhouse (Schist, Gneiss)

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Figure A 1-27 Plot Plan (P-34)

Figure A 1-28 Longitudinal Profile (P-34)

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1.15 P-34R: Darachhu_Rev

Project P-34R: Darachhu_Rev Date 18/01/2019 Name Basin Punatsangchhu Tributary Darachhu Dam (Weir) Latitude: 27° 6' 3.32" N Longitude: 89° 47' 2.28" E Powerhouse Latitude: 27° 3' 15.70" N Longitude: 89° 54' 28.08" E Type ROR RBL at Dam EL 1,640 m

Installed Dam/Weir 89 MW 5 m Capacity Height Primary Data Max. 15.3 m3/s Salient Crest Length 30 m General Discharge Features Features Effective Waterway 674.3 m 14,067 m Head Length Catchment Live Storage 220 km2 MCM Area Capacity

Elongation from Dam site: 15 km from the Main Road Existing Road Powerhouse and Outlet Site：0.5 km from Local Road

Access

River Flow Rate 3.0 – 3.5 m3/s (Inferred from discharge at the confluence point) (Eye Measurement)

Hydrology Sediment N.A. General Geology Geofacies (compiled by Long et al., 2011) are as follows: The subsurface geology of the project area belongs to the Upper metasedimentary unit in the Structurally-lower Greater Himalayan section in the Greater Himalayan Zone of the Neoproterozoic-Ordovician [?] period. Variable metamorphic grades; dominantly amphibolite facies (Gansser, 1983), partial melt- and often kyanite-, sillimanite-, or staurolite-bearing paragneiss, schist, and quartzite in the east (Grujic et al., 2002) and near the base in west-central Bhutan, and melt-free, dominantly upper greenschist- facies (Gansser, 1983) quartzite and biotite-muscovite-garnet schist in central Bhutan (Long and McQuarrie, 2010).

 Mica Schist is observed surrounding Dagana Dzong, and Gneiss is distributed downstream of the Powerhouse site along Dagachhu. These strata are inclined gently to the north.

Geography / Geology  According to the existing Pre-feasibility Report for Dagachhu II Hydropower project by the ADB/ Mott MacDonald issued in May 2016, “gneissose quartzite with some thin bands of quartz mica schist and quartzitic gneiss” are recorded on the Darachhu river floor, which is located in the middle part of the waterway.  No large-scale collapse or obvious lineaments have been verified across the whole project area, but a small-scale lineament is observed on the waterway close to the weir site on the Google Earth image.

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Weir / Intake  In consideration of Long’s geological map, the Pre-feasibility Report and the JICA team’s survey results, the geology around the weir site is assumed to be Mica Schist, which is the upper horizon of “gneissose quartzite with some thin bands of quartz mica schist and quartzitic gneiss” investigated far downstream of the weir site. Since the overall strata are inclined gently to the north, it is assumed that the geology of the weir site is mica schist.

Waterway  In line with the revision of the Dagachhu II plot plan, the outlet site is shifted downstream as far as possible.  Although the geology along the waterway route was not observed, mica schist, quartzite and gneiss will be in order along the headrace tunnel and penstock. It is assumed that the RMR evaluation point marks 58 and the rock classification is mainly Class-III (Photo 4).  Subsurface geological conditions surrounding the surge tank and penstock route are not stable enough for setting an open-air penstock. Accordingly, an underground type penstock is recommended.

Powerhouse Observed with drone  Since the slope where the Powerhouse is planned to be located is uniformly inclined at around 40°, and no landslides or mass rock creeping have been observed, the slope seems to be stable. Degree of weathering or loosening is assumed to be low (Photo 1).  The geology around the Powerhouse site is assumed to be Gneiss, judging from all the geological information mentioned above in “General Geology”. The overall geological structure is NW-SE strike and is inclined 5 - 20° to the north.

Natural Park /  The project area is outside the protected area. However, the waterway Protected Area passes underground near a Heritage Forest, in which development is strictly regulated by the Forest and Nature Conservation Act 1995.

Prosperous fauna /  The weir site is covered by pure cool broad-leaved trees (interview with flora forest office), but the sites of the waterway, surge-tank and powerhouse

are covered with mixed forest composed of cool broad-leaved such as Java Ceder, Parasol leaf tree and conifer of chir pine forest of Pinus roxburghii.  The right flank of the weir is contiguous with the Heritage Forest, but it does not cause impact on the trees of Heritage Forest as its area is vertical rock with no growing trees.  There are some small mountain flows downstream, but flowing is not anticipated during any time of the year.  In terms of endangered species designated by the IUCN, according to an interview with the forest office, Cycas Pectinata (VU), Rufous-necked

Natural / Social Environment Hornbill (VU) White-bellied Heron (CR), and Tiger (EN) have been confirmed at the project site.

Resettlement / Compensatory  N/A assets  The surface land of the PH site is private land with paddies.

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Historical /  N/A Cultural Heritage Other  People see the project as one of the most effective elements for fast socio-economic development of the gewog. Therefore, the people would welcome the project.

 Poverty rates are better (around 20%) than the average of the whole Dzongkhag. They requested us to widen and improve the existing road in the Gewogs.  There is no road to the site at present. Better road access and network will help promote market access and tourism (a trekking course is under development).

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PS

Photo 1 Powerhouse Site

Photo 2 Mica Schist observed at Dagana Dzong Photo 3 Quartzite boudin in Mica Schist

Photo 4 Waterway Route

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Figure A 1-29 Plot Plan (P-34_Rev)

Figure A 1-30 Longitudinal Profile (P-34_Rev)

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1.16 P-35: Dagachhu-II

Project Name P-35: Dagachhu-II Date 14, 15/11/2018 Basin Punatsangchhu Tributary Darachhu, Dagachhu Latitude: 27° 4' 39.37" N Longitude: 89° 53' 19.16" E Dam (Weir) 27° 3' 55.78" N 89° 52' 29.32" E

Powerhouse Latitude: 27° 2' 26.14" N Longitude: 90° 6'18.85"E EL 1,130 m Type ROR RBL at Dam EL 1,120 m Installed Dam/Weir 29 (14) m 94 MW Capacity Height 35 (10) m Primary Data Max. Salient 50 m 41.2 m3/s Crest Length General Discharge Features 70 m Features Effective Waterway 1,965 m 265.1 m Head Length 5,484 m Catchment Live Storage 593 km2 MCM Area Capacity Elongation from Dam site: 1km to No. 1 Dam site and 1km to No. 2 Dam site Existing Road Powerhouse Site: 1.0 km from Dagachhu HPP Dam site Access

River Flow Rate Dagachhu: 4 - 5 m3/s (Eye Measurement) Darachhu: 4 - 5 m3/s

Hydrology Sediment 0.5 – 5m Boulder General Geology Geofacies (compiled by Long et al., 2011) are as follows: The subsurface geology of the project area belongs to the Upper metasedimentary unit in the Structurally-lower Greater Himalayan section in the Greater Himalayan Zone of the Neoproterozoic-Ordovician [?] period.

Variable metamorphic grades; dominantly amphibolite facies (Gansser, 1983), partial melt- and often kyanite-, sillimanite-, or staurolite-bearing paragneiss, schist, and quartzite in the east (Grujic et al., 2002) and near the base in west-central Bhutan, and melt-free, dominantly upper greenschist- facies (Gansser, 1983) quartzite and biotite-muscovite-garnet schist in central Bhutan (Long and McQuarrie, 2010).

 Schist and Gneiss are distributed around both Dam site (1) and (2). In Geography / Geology consideration of Long’s geological map, the same geology is assumed to be distributed across the whole project area.  In the Google Earth image, no large-scale collapsed land or clear lineament have been verified across the whole project area.

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Dam / Intake 【Dam (1)】Observed with drone  Topography of the left bank of the Dam forms a steep cliff. The slope of the right bank of the Dam is uniformly inclined at 40 - 50° and no landslides or mass rock creeping have been observed (Photos 1, 2, and 3).  Degree of weathering or loosening is assumed to be low.  River gravel is thickly deposited in the riverbed. The size of boulders is from 0.5m to 5m and their shape is round. River gravel is widely distributed at the confluence with the tributary 200m downstream of the Dam (Photos 4 and 5).

【Dam (2)】Observed with drone  Topography of the right bank of the Dam forms a steep cliff. Since the slopes on the left banks are covered by vegetation, geological conditions are unknown, but it is assumed that the slope is uniformly inclined at about 40° (Photo 6).  Degree of weathering or loosening is assumed to be low.  The geology around the Dam site is assumed to be Gneiss and Schist, judging from the outcrops along Dagachhu downstream of the Dam site. The overall geological structure is assumed to be NW-SE strike and to be inclined gently 5 - 20° to the north (Photo 7).  River gravel is thickly deposited in the riverbed. The size of boulders is from 0.5m to 1m and their shape is round (Photo 8).  There is an intake for an existing Mini hydropower plant just downstream of the Dam (Photos 9 and 10).

Waterway  Although the geology along the waterway route was not observed, if it has similar characteristics to that of the Dam site, it is assumed that the RMR evaluation point marks 58 and the rock classification is mainly Class-III.

Powerhouse  The geology around the Powerhouse site is assumed to be Gneiss which outcrops could be observed downstream of Powerhouse site along Dagachhu (Photo 11, 12).

Natural Park /  The project area is outside the protected area. However, a part of Protected Area waterway connected from weir II (2) to powerhouse pass through under the Heritage Forest which development is strictly regulated by the Forest and Nature Conservation Act 1995.

Prosperous fauna /  The weir site of II (2) and I (1) are covered by shrub with broad-leaved flora trees such as Orange jessamine, and site of waterway, surge-tank and powerhouse is covered with mixed forest composed of cool broad-leaved such as Java Ceder, Parasol leaf tree and conifer of chir pine forest composed of Chir pine.  The right flank of the weir of II (2) is contiguous with the Heritage Forest, but it will not cause an impact on the trees of the Heritage Forest as its area is vertical rock with no growing trees.  There are some small mountain flows downstream, but flowing is not anticipated during any time of the year.  In terms of endangered species designated by the IUCN, according to an Natural / Social Environment interview with the forest office, Cycas Pectinata (VU), Rufous-necked Hornbill (VU) White-bellied Heron (CR), and Tiger (EN) have been confirmed at the project site.

Resettlement /  N/A Compensatory assets

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Historical / Cultural  There is a possibility that there are 3 holy sites in the vicinity of the PH Heritage area and surge tank. Further investigation is required.

Other  Gewog officers mentioned that local people would show a positive attitude toward the plan if they are given sufficient and proper compensation. They welcome the idea of implementing hydropower projects as they believe that such projects can boost the local economy, and improve local facilities and the livelihoods of the people.

 Poverty level (around 20%) is better than the average for the whole Dzongkhag. Market access will be improved due to the road improvement, where local food items (vegetables, poultry, rice, fruits, etc.) will be able to be sold.  Population increase during the construction period will result in enhancement and upgrade of school and hospital levels (e.g., from BHU to ORC).

 Preservation and improvement of religious sites will attract tourism.  Gewog officers request that no impacts such as noise or vibration be caused to the Dzong (even during underground construction work).

 On and around the surface of the PH, there are 150 acres owned by 31 households. The land is currently used as cultivated land for paddies, maize, cardamom and oranges, and house cattle (cows) that live on wheat.

Dam (1) Left bank Dam (1)

Darachhu

Photo 1 Dam site (1) Photo 2 Dam site (1) View from Downstream

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Left bank

Right bank

Photo 3 Dam site (1) Bird’s Eye View

Photo 4 Riverbed around 200m downstream of Dam Photo 5 Right Bank of Dam around 400m downstream

Photo 6 Right Bank of Dam (2)

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Photo 7 Right Bank of Dam (Gneiss Outcrop) Photo 8 Riverbed downstream of Dam (2)

Photo 9 Existing Mini Hydropower Photo 10 Intake of Existing Mini Hydropower PH

Photo 11 Powerhouse Site Photo 12 Powerhouse Site (Gneiss Outcrop)

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Figure A 1-31 Plot Plan (P-35)

Figure A 1-32 Longitudinal Profile (P-35)

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1.17 P-35R: Dagachhu-II_Rev

Project Name P-35R: Dagachhu-II_Rev Date 17/01/2019 Basin Punatsangchhu Tributary Dagachhu Dam (Weir) Latitude: 27° 6' 08.47" N Longitude: 89° 52' 26.28" E

Powerhouse Latitude: 27° 2' 55.47" N Longitude: 89° 54' 57.45" E Type ROR RBL at Dam EL 1,270 m

Installed Dam/Weir 71 MW 5 m Capacity Height Primary Data Max. 21.3 m3/s Salient Crest Length 30 m General Discharge Features Features Effective Waterway 386.0 m 8,100 m Head Length Catchment Live Storage 307 km2 MCM Area Capacity

Elongation from Intake Weir Site: 2 km from Local Road Existing Road Powerhouse Site: 1.5 km from Dagachhu HPP Dam site

Access Outlet Site: 0.3 km from Dagachhu HPP Dam site

3

River Flow Rate 4 - 5 m /s (Eye Measurement)

Hydrology Sediment 0.5 – 3 m Boulder General Geology Geofacies (compiled by Long et al., 2011) are as follows: The subsurface geology of the project area belongs to the Upper metasedimentary unit in the Structurally-lower Greater Himalayan section in the Greater Himalayan Zone of the Neoproterozoic-Ordovician [?] period. Variable metamorphic grades; dominantly amphibolite facies, partial melt- and often kyanite-, sillimanite-, or staurolite-bearing paragneiss, schist, and quartzite near the base in west-central Bhutan (Gansser, 1983).

 According to the existing Pre-feasibility Report for Dagachhu II Hydroelectric project by the ADB/Mott MacDonald issued in May 2016, “gneissose quartzite with some thin bands of quartz mica schist

Geography / Geology and quartzitic gneiss” are recorded in this area.  A cross section from north to south via Dagachhu and Darachhu (red line on the Google Earth image) is shown in the profile shown below.  In the Google Earth image, no large-scale collapse is observed, but a lineament crosses the waterway near the intake.

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Weir / Intake Observed with drone  Diversion of Darachhu is abandoned and the two intake dams are changed to a weir which is shifted to the confluence point with a tributary.  Intake site is located at a narrow gorge of Dagachhu just downstream of the confluence with Pelrichhu (Photo 1).  It is probable that huge rolling stones of more than several meters diameter scattered on the riverbed have a thickness of more than 5m (Photos 2 and 3).  Fresh abutments for both right and left bank are expected, referring to the existing Pre-feasibility Report for Dagachhu II Hydropower project by the ADB/Mott MacDonald issued in May 2016. A boring, BH-1, was carried out at the riverbed. The overburden was 7.8m and the UCS (unconfined compressive strength) value varied from 22.4 to 49.5MPa.  Accordingly, there are no particular difficulties in constructing the weir.

Waterway  Waterway route is shifted to the left bank of Dagachhu, since the mountain slope is steeper, the geological conditions are better and its length is shorter.  Although the geology along the waterway route was not observed, it is assumed that the RMR evaluation point marks 63 and the rock classification is mainly Class-II, because almost all of the headrace tunnel will run in Gneiss.  An investigation to verify the characteristics of the upper reach of the waterway, where a lineament crosses the route (Photo 4), will be required.

Powerhouse  The geology around the Powerhouse site is assumed to be Gneiss, of which outcrops could be observed downstream of the Powerhouse site along Dagachhu (Photo 5).

Natural Park /  The project area is outside the protected area. Protected Area Prosperous fauna /  The weir site is covered by shrubs with broad-leaved trees such as flora Orange jessamine. The sites of the waterway, surge-tank and

powerhouse are covered with mixed forest composed of cool broad- leaved such as Java Ceder, Parasol leaf tree and conifer of chir pine forest composed of Chir pine.  There are some small mountain flows downstream, but flowing is not anticipated during any time of the year.  In terms of endangered species designated by the IUCN, according to an interview with the forest office, Cycas Pectinata (VU), Rufous-necked Hornbill (VU) White-bellied Heron (CR), and Tiger (EN) have been confirmed at the project site.

Natural / Social Environment Resettlement /  N/A Compensatory assets Historical / Cultural  N/A Heritage

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Other  Gewog officers mentioned that local people would show a positive attitude toward the plan if they are given sufficient and proper compensation. They welcome the idea of implementing hydropower projects as they believe that such projects can boost the local economy, and improve local facilities and the livelihoods of the people.

 Poverty level (around 20%) is better than the average across the whole Dzongkhag. Market access will be improved due to the road improvement, where local food items (vegetables, poultry, rice, fruits, etc.) will be able to be sold.  Population increase during the construction period will enhance and upgrade school and hospital levels (e.g., from BHU to ORC)

 Gewog officers request that no impacts such as noise or vibrations be caused to the Dzong (even during underground construction work).

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Left bank

Photo 1 Intake Weir Site

Photo 2 Riverbed Condition Photo 3 Riverbed Materials

Photo 4 Morphologic gap where a lineament crosses Photo 5 Waterway, Surgetank, Penstock and the headrace tunnel in the upper part of the waterway Powehouse

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Figure A 1-33 Plot Plan (P-35_Rev)

Figure A 1-34 Longitudinal Profile (P-35_Rev)

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Figure A 1-35 Geological Profile (N-S Section)

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1.18 P-38: Tashiding

Project Name P-38: Tashiding Date 14, 16/11/2018 Basin Punatsangchhu Tributary Dagachhu Dam (Weir) Latitude: 26° 57' 44.84" N Longitude: 89° 57' 37.72" E

Powerhouse Latitude: 26° 55' 1.36" N Longitude: 90° 1' 20.18" E Type ROR+Pond RBL at Dam EL 500 m Installed Dam/Weir 81 MW 53 (9) m Capacity Height

Primary Data Max. 53.6 m3/s Salient Crest Length 140 m General Discharge Features Features Effective Waterway 175.8 m 8,207 m Head Length Catchment Live Storage 788 km2 1.1 MCM Area Capacity Elongation from Dam site: 0.3km from Dagachhu HPP Outlet Existing Road Powerhouse Site: 5km (Tunnel part: 1km) Access

River Flow Rate About 13 m3/s (Dagachhu HPP Discharge: 10 m3/s) (Eye Measurement)

Hydrology Sediment 0.3 – 5m (Gravel ~ Boulder) General Geology Geofacies (compiled by Long et al., 2011) are as follows: 【Dam~Waterway】 The subsurface geology of the project area belongs to the Lower metasedimentary unit in the Structurally-lower Greater Himalayan section in the Greater Himalayan Zone of the Neoproterozoic-Cambrian [?] period. Dominantly amphibolite-facies (Gansser, 1983; Grujic et al., 2002; Daniel et al.,2003) metasedimentary rocks, including quartzite, and biotite-muscovite- garnet schist and paragneiss often exhibiting kyanite, sillimanite, or staurolite, and partial melt textures** (Long and McQuarrie, 2010). Orthogneiss intervals locally split out. Up to ~5.0 km-thick; thickens toward western Bhutan.

【Powerhouse】 The subsurface geology of the project area belongs to the Jaishidanda Formation in the Lesser Himalayan Zone of the Neoproterozoic-Ordovician [?] period. Gray, biotite-rich, locally garnet-bearing schist, interbedded with gray to tan, biotite lamination-bearing, lithic clast-rich quartzite (Bhargava, 1995; Dasgupta, 1995; Long et al., 2011A). Typically 600-900 m-thick, but 1,700 Geography / Geology m-thick along Kuri (Long et al., 2011A). Upper greenschist to lower amphibolite facies (Gansser, 1983).

 The site is characterized by mass rock creeping on the left bank of Dagachhu and a large-scale landslide around the Powerhouse site.  Schist and Gneiss are distributed from the Dam site to the Waterway route. In consideration of Long’s geological map, the geology around the Powerhouse site is assumed to be Schist and Quartzite and MCT is assumed to be distributed around the Powerhouse site.

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Dam / Intake  Mass rock creeping on the left bank of the Dam site is in a progressed state and land collapses have occurred in some places. Degree of weathering or loosening is high (Photos 1, 2, 3, and 4).  There was information that the rock surrounding the surge tank of the existing Dagachhu HPP collapsed during excavating. Since mass rock creeping is also observed around the surge tank, it is assumed that the collapse occurred due to excavating loosened rock (Photo 5).  The geology around the Dam site is assumed to be mainly Schist (Photo 6).  The overall geological structure is assumed to be NW-SE strike and to be inclined 10 - 30° to the northeast.  River gravel is deposited in the riverbed and the thickness is unknown. Boulders are mainly large and round.

Waterway  Although the geology along the waterway route was not observed, if the geology has similar characteristics with that of Dam site. It is assumed that RMR evaluation point marks 40 and the rock classification is mainly Class-IV. The rock classification grade is assumed to be lower as it is nearer the powerhouse site affected by MCT.

Powerhouse  In consideration of Long’s geological map, Powerhouse site is assumed to locate within the range of MCT’s affect. In the Google Earth image, many collapsed areas affected by MCT are observed, but clear lineament have not been verified across the whole project area.

Natural Park /  The project area is outside the protected area. Protected Area Prosperous fauna /  The site of pond, waterway, surge-tank and powerhouse is covered with flora mixed forest composed of cool broad-leaved such as Java Ceder, Parasol leaf tree and conifer of chir pine forest composed of Pinus roxburghii.  As an endangered species designated by IUCN, according to interview at forest office, Rufous-necked Hornbill (VU) and White-bellied Heron (CR), Tiger (EN) is being confirmed at the project site.

Resettlement / Compensatory assets  There are 20 acres of private land owned by 6 households. The land is currently used as cultivated land.

Natural / Social Environment  N/A

Historical / Cultural  N/A Heritage

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Other  Gewog officers say local people will welcome the project if they are provided more fertile land substitute of their current land.

 Poverty rate is the 3rd worst in Dagana Dzongkhag. Road quality shall be improved. Roads will be widened and transportation enhanced. Employment, and an enhancement of dairy product business (vegetables, rice, livestock, chicken and eggs) is expected.  Schools and health facilities are expected to be enhanced and improved.

 Spread of infectious diseases (for both humans and animals) was experienced by DHPP. They are concerned about when the construction starts.  Landslides occur a lot on the present waterway route up to the powerhouse. Gewog officers recommend reconsidering the waterway route, changing it from the south of the river to the north.

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Photo 1 Mass Rock Creeping on Left Bank of Dam Site

Photo 2 Dam Site

Photo 3 Collapse on Left Bank of Dam site Photo 4 Collapse due to Mass Rock Creeping

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Photo 5 Surge Tank of Dagachhu HPP Photo 6 Outcrop around 1km upstream of Dam site (Schist)

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Figure A 1-36 Plot Plan (P-38)

Figure A 1-37 Longitudinal Profile (P-38)

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1.19 M-5: Bemji

Project Name M-5: Bemji Date 19/11/2018- Basin Mangdechhu Tributary Mangdechhu Dam (Weir) Latitude: 27° 42' 14.61" N Longitude: 90° 28' 57.46" E

Powerhouse Latitude: 27° 34' 24.31" N Longitude: 90° 27' 48.52" E Type ROR+Pond RBL at Dam EL 2,530 m Installed Dam/Weir 333 MW 88 (23) m Capacity Height

Primary Data Max. 71.6 m3/s Salient Crest Length 180 m General Discharge Features Features Effective Waterway 539.4 m 16,421 m Head Length Catchment Live Storage 1,010 km2 1.2 MCM Area Capacity Elongation from Dam site: Approximately 10 km Existing Road (improvement of 25km-long existing road is required) Access Powerhouse Site: 0 km General Geology Geofacies (compiled by Long et al., 2011) are as follows: The subsurface geology of the project area falls in the Structurally-lower Greater Himalayan section in the Greater Himalayan Zone of the Neoproterozoic-Ordovician [?] period. The upper half of the waterway route belongs to the Upper metasedimentary unit (GHlmu), with variable metamorphic grades: dominantly amphibolite facies (Gansser, 1983), partial melt- and often kyanite-, sillimanite-, or staurolite-bearing paragneiss, schist, and quartzite in the east (Grujic et al., 2002) and near the base in west-central Bhutan, and melt-free, dominantly upper greenschist-facies (Gansser, 1983) quartzite and biotite-muscovite- garnet schist in central Bhutan (Long and McQuarrie, 2010). The lower half of the waterway route belongs to the Orthogneiss unit (GHlo) from the Cambrian to the Ordovician Period. Cliff-forming, massive-

weathering, granite-composition orthogneiss; generally, exhibits leucosomes and abundant feldspar augen. Paragneiss, schist, and quartzite intervals locally split out. Interpreted as deformed Cambrian-Ordovician granite plutons that intruded upon the Greater Himalayan sedimentary protoliths and which thicken toward eastern Bhutan.

Dam / Intake  Though the JICA survey team couldn’t reach the site, there seem to be no particular issues regarding dam construction. Geography / Geology  Concrete gravity dam seems to be preferable in view of the morphological and geological features.  Construction material for the dam is recommended to make use of a quarry candidate which is located within 1 km downstream of the dam.

Waterway  The subsurface geology of the waterway route belongs to the Structurally- lower Greater Himalayan section. Therefore, the rocks along the headrace tunnel seem to be preferable.  Weathering grade mostly seems to be Slightly Weathered (SW), but the lowermost part, which faces the SE slope, seems to be Moderately Weathered (MW), since there are some gentle slopes which were most likely formed by landslides.  The rock seems to belong mainly to Class-II, for which the RMR value is estimated at 65.

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Powerhouse  The underground powerhouse is located under Bemji Village.  Bedrock conditions of the underground powerhouse may have no particular issues regarding the stability of the cavern, but the location is just under the Dzong so social/environmental issues should be taken care of.

Natural Park /  The intake is Wangchuk Centennial National Park. Protected Area  About 2/3 of the waterway (underground) is within the national park.

Prosperous fauna /  Blue Pine Forest covers the intake and waterway area (from Google Earth flora photographs). The power plant area is in the village of Bemji, which is surrounded by Blue Pine Forest.  According to villagers from Karshong, a nearby village, there are Leopard (VU) and Asiatic Black Bear (VU) in the area, and otters (species unknown) may also be present.  According to a park ranger of Jigme Singye Wangchuk National Park (Trongsa Office), the North Biological Corridor (located west of the project area) is an important corridor for Tiger (EN). Although the project area is not in the Biological Corridor, careful consideration should be given to the conservation of Tigers. The ranger also stated that there are Red Panda (EN), Takin (VU), Leopard (VU) and Asiatic Black Bear (VU) in the area.

Resettlement / According to the GIS data from NLC and interview with the Nubi Gewog and Compensatory assets village representatives (Tshopas),  No resettlement is required.  Private land for agriculture is in the powerhouse location.

Historical / Cultural  According to the GIS data from NLC and interview with the Nubi Gewog Heritage and village representatives (Tshopas), no historical or cultural heritage sites are directly affected; however, in the peripheral area, there are some cultural sites as per the below:

Natural / Social Environment - Approx. 300 m from the powerhouse, there is a cultural heritage site at one of the oldest houses in the community, "Bemji Naktshang". - Approx. 80 m from the waterway, there is a cultural site where residents of the community make offerings to a local deity (god) named "Menmo Tashi Yangzom".

Other  Noteworthy additional positive social impacts are not expected to any great extent since the project site is located in a relatively better off area, where there is already a vehicle-accessible road connection.

 From the experience of Mandechhu hydropower project, officials at the Dzongkhag mentioned that there are serious concerns and fears that the development of HP and associated infrastructure is causing stress on the Dzong and on other assets in the town due to all the explosions and vibrations caused by construction.

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Photo 1 Waterway, Surge Tank and Penstock

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Figure A 1-38 Plot Plan (M-5)

Figure A 1-39 Longitudinal Profile (M-5)

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1.20 M-6: Jongthang

19/11/2018 Project Name M-6: Jongthang Date 20/11/2018 Basin Mangdechhu Tributary Mangdechhu Dam (Weir) Latitude: 27° 33' 39.17" N Longitude: 90° 27' 0.79" E Powerhouse Latitude: 27° 29' 39.23" N Longitude: 90° 30' 17.38" E

RBL at Type ROR+Pond EL 1,907 m Dam Installed Dam/Weir 164 MW 138 (40) m Capacity Height

Primary Data Max. Crest 93.1m3/s Salient 240 m Discharge Length General Features Effective Waterway Features 204.6 m 8,262 m Head Length Live Catchment 1,314 km2 Storage 28.3 MCM Area Capacity

Elongation from Existing Dam site: Dam site accessible via the existing road, 1 hour by car from Road Trongsa Town Powerhouse Site: Dam site accessible via the existing road, located in Access Trongsa Town General Geology Geofacies (compiled by Long et al., 2011) are as follows: Subsurface geology of the project area belongs to the Orthogneiss unit (GHlo) from the Cambrian to the Ordovician Period in the Structurally- lower Greater Himalayan section of the Greater Himalayan Zone in the Neoproterozoic-Ordovician [?] period. Cliff-forming, massive-weathering, granite-composition orthogneiss; generally, exhibits leucosomes and abundant feldspar augen. Paragneiss, schist, and quartzite intervals locally split out. Interpreted as deformed

Cambrian-Ordovician granite plutons that intruded Greater Himalayan sedimentary protoliths thickens toward eastern Bhutan.

Dam/ Intake  Since many landslide-prone slopes are observed surrounding the original and revised dam sites and their reservoir areas, decreasing the reservoir water level seems to be a much safer way to maintain the stability of the slope. Therefore, it was proposed to shift the dam

Geography / Geology location approximately 2km downstream of the junction of Mangdechhu and its tributary. Though the water head will decrease, water flow from the additional tributary can be used and the waterway length can be shorter.  Topography of both bank slopes of the dam site is steep and V-shaped. Massive gneiss is expected for the dam foundations at the dam site.  The ridge just 0.5km upstream of the dam site, which forms at the winding of the river, could be utilized as a quarry for construction materials.

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Waterway  By shifting the dam site downstream, the length of the waterway becomes shorter than the original one.  Gneiss, quartzite, and thin schist may be repeatedly distributed along the headrace tunnel judging by observations along the national road in the western part of Trongsa Town.  The rock classification along the headrace tunnel is estimated to be mainly Class-II, for which the RMR value is estimated to be 69.

Powerhouse  The original powerhouse and outlet are located near the Trongsa Dzong in Trongsa City. Even if they are located far underground, it would seem to be difficult to get local consent for construction of the project. Therefore, it is recommended to shift them 0.8km upstream of the original ones. With this change in the locations, the water head for generation decreases by approximately 30m.  The powerhouse is to be underground to avoid influence on Trongsa Town and because there is limited space for an open-air type of powerhouse.  The geology around the powerhouse site is assumed to be massive gneiss, which is relatively stable for excavation of an underground powerhouse.

Natural Park / Protected  The project area is outside protected areas. Area Prosperous fauna / flora  Blue Pine Forest covers the right bank, and Cool Broad-leaved Forest covers the left bank of the alternative site for the intake.  Blue Pine Forest covers the right bank, and Cool Broad-leaved/Chir Forest covers the left bank of the original site for the intake.  Cool Broad-leaved Forest covers the waterway and outlet area.  According to villagers from Karshong, a nearby village, there are Leopard (VU) and Asiatic Black Bear (VU) in the intake area, and otters (species unknown) may be present in the intake area.

Resettlement / According to the GIS data from NLC and interview with Nubi Gewog and Compensatory assets village representatives (Tshopas),  No resettlement is required.  In the dam site and reservoir area, acquisition of approx. 16 acres of private land for agriculture and grazing, and community land is

Natural / Social Environment required. Some cowsheds and other huts are affected, too. Thus, impacts on crops and livestock activities are predicted.

Historical / Cultural  According to the GIS data from NLC and interview with Nubi Gewog Heritage and village representatives (Tshopas), in dam site and reservoir area, no cultural heritage is directly affected.

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Other  The Waterway runs through the upper middle part of the Trongsa Municipality and would impact (damage) multiple public infrastructure installations and private houses, and may affect the National Museum above the Trongsa Dzong.  Noteworthy additional positive social impacts are not expected to any great extent since the project site is located in a relatively better off area in Trongsa, where there is already a vehicle-accessible road connection.

 From the experience of Mandechhu hydropower project, officials at the Dzongkhag mentioned that there are serious concerns and fears that development of HP and associated infrastructure is causing stress on the Dzong and on other assets in the town due to all the explosions and vibrations caused by construction.

Other (Special Note)  Revised versions of Trongsa Reservoir and Powerhouse require acquisition of private land used for agriculture and pasture.  Revised version of the waterway runs partly through private land used for agriculture and grazing.

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Photo 1 Weir Site Photo 2 Candidate for Quarry

Photo 3 Gneiss exposed along Road which is expected Photo 4 View of Surge Tank and Powerhouse Site to be along Waterway Route

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Figure A 1-40 Plot Plan (M-6)

Figure A 1-41 Longitudinal Profile (M-6)

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1.21 M-6R: Jongthang_Rev3

Project Name M-6R: Jongthang_Rev3 Date 21/01/2019 Basin Mangdechhu Tributary Mangdechhu Dam (Weir) Latitude: 27° 36' 18.15" N Longitude: 90° 29' 52.02" E Powerhouse Latitude: 27° 30'11.41" N Longitude: 90° 29' 18.88" E

RBL at Type ROR+Pond EL 2,100 m Dam Installed Dam/Weir 232 MW 51 (21) m Capacity Height

Primary Data Max. Crest 85.0m3/s Salient 140 m Discharge Length General Features Effective Waterway Features 316.2 m 14,721 m Head Length Live Catchment 1,200 km2 Storage 0.3 MCM Area Capacity

Elongation from Existing Dam site: Dam site accessible via the existing road, 1 hour by car from Road Trongsa Town

Access Powerhouse Site: Dam site accessible via the existing road, located in Trongsa Town 3

River Flow Rate About 15 m /s

(Eyeogy Measurement) Hydrol Sediment Riverine sand and cobble/boulder bed General Geology Geofacies (compiled by Long et al., 2011) are as follows: Subsurface geology of the project area belongs to the Orthogneiss unit (GHlo) from the Cambrian to the Ordovician Period in the Structurally- lower Greater Himalayan section of the Greater Himalayan Zone in the Neoproterozoic-Ordovician [?] period. Cliff-forming, massive-weathering, granite-composition orthogneiss; generally, exhibits leucosomes and abundant feldspar augen. Paragneiss, schist, and quartzite intervals locally split out. Interpreted as deformed Cambrian-Ordovician granite plutons that intruded Greater Himalayan sedimentary protoliths thickens toward eastern Bhutan.

 Deep weathering is observed, along the winding forest road from Trongsa to the project site, on the top of the broad plain in most areas, especially the upstream side of the project area.

Dam/ Intake  Since the M-5 site was very hard to develop due to it being inside a protected area, the dam site was shifted to the upmost stream outside of the protected area. Geography / Geology  Since many landslide-prone slopes are observed around the Rev 3 dam site and its pond area, the dam site was shifted to the upmost stream and the dam height was lowered less than 30m (Photos 1 and 2).  Topography of both bank slopes at the dam site is gentle at around 30 degrees. The river, the width of which is about 50m, is covered by recent riverine sand and cobble/boulder bed (Photo 2).  No outcrops are observed surrounding the intake area. No quarry sites are expected, so a fill type dam or an earth dam is recommended. Earth materials such as mudflow and terrace deposits will be easily obtained from the surrounding area.

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Waterway  Orthogneiss may be distributed along the headrace tunnel, although its outcrops are rarely observed due to deep weathering (Photo 3).  The rock classification of most of the downstream part of the headrace tunnel is estimated to be Class-III, for which the RMR value is estimated to be 57. However, 1/4 to 1/3 of the upstream part seems to be worse because of weathering.

Powerhouse  The original powerhouse and outlet were located near the Trongsa Dzong in Trongsa City. Even if they were located far underground, it seems it would be difficult to obtain local consent for construction of the project. Therefore, it is recommended to shift them 0.8km upstream of the original ones. With this change in the locations, the water head for generation decreases by approximately 30m.

 The powerhouse is to be underground to avoid influence on Trongsa Town and because there is limited space for an open-air type of powerhouse.

 The geology around the powerhouse site is assumed to be massive gneiss, which is relatively stable for excavation of an underground powerhouse.

Natural Park / Protected  The project area is outside protected areas. Area Prosperous fauna / flora  Blue Pine Forest covers the right bank, and Cool Broad-leaved Forest covers the left bank of the alternative site for the intake.  Blue Pine Forest covers the right bank, and Cool Broad-leaved/Chir Forest covers the left bank of the original site for the intake.  Cool Broad-leaved Forest covers the waterway and outlet area.  According to villagers from Karshong, a nearby village, there are Leopard (VU) and Asiatic Black Bear (VU) in the intake area, and otters (species unknown) may be present in the intake area.

Resettlement / According to the GIS data from NLC and interview with Nubi Gewog and Compensatory assets village representatives (Tshogpas),  No resettlement is required.  In the dam site and reservoir area, part of private land for agriculture and grazing and a cowshed/hut may be affected, too.

Historical / Cultural  According to the GIS data from NLC and interview with Nubi Heritage Gewog and village representatives (Tshopas), in the dam site and reservoir area, no cultural heritage is directly affected by the dam site or the powerhouse.

Natural / Social Environment Other  Waterway runs under part of private agricultural land.  Noteworthy additional positive social impacts are not expected since the project site is located in a relatively better off area, where there is already a vehicle-accessible road connection.

 From the experience of Mandechhu hydropower project, officials at the Dzongkhag mentioned that there are serious concerns and fears that the development of HP and associated infrastructure is causing stress on the Dzong and on other assets in the town due to all the explosions and vibrations caused by construction.

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Right bank

Left bank

Photo 1 Dam Site_Rev3 (Height : 60m) Photo 2 Final dam Site (Height: 30m) (No bedrock was observed on the left bank)

Photo 3 Gneiss exposed along Road which is Photo 4 Surge Tank and Powerhouse Site expected to be along Waterway Route

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Figure A 1-42 Plot Plan (M-6_Rev3)

Figure A 1-43 Longitudinal Profile (M-6_Rev3)

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1.22 M-11R: Wangdigang_Rev

Project Name M-11R: Wangdigang_Rev Date 20/11/2018, 09/03/2019 Basin Mangdechhu Tributary Mangdechhu Dam (Weir) Latitude: 27° 19' 51.14" N Longitude: 90° 34' 57.28" E

Powerhouse Latitude: 27° 13' 36.87" N Longitude: 90° 37' 2.35" E Type ROR+Pond RBL at Dam EL 910 m Installed Dam/Weir 502 MW 126 (26) m Capacity Height

Primary Data Max. 176.4 m3/s Salient Crest Length 200 m General Discharge Features Features Effective Waterway 330.2 m 13.268 m Head Length Catchment Live Storage 2,490 km2 22.4 MCM Area Capacity Elongation from Dam site: Dam site accessible via the existing road Existing Road Powerhouse Site: Powerhouse site accessible via the existing road Access General Geology Geofacies (compiled by Long et al., 2011) are as follows: The subsurface geology of the project area belongs to the Tethyan Himalayan Zone in the Ordovician or younger age. The geological structure of this site has a south dipping monoclinic form, and there is a synclinal axis around the powerhouse site. The upper half of the waterway route belongs to the Chekha Formation (Pzc). This unit has dominantly upper greenschist facies, with thick- bedded, fine to medium-grained, cliff-forming, micaceous quartzite, interbedded with biotite-muscovite-garnet schist. The lower half of the waterway route belongs to the Maneting Formation

(Pzm). Its facies are dark-gray, graphitic, crenulated, finely-laminated, biotite-garnet phyllite.

Dam / Intake  The dam site is located 5km downstream from the outlet of Mangdechhu Power Plant. So, FRL of the dam should be set considering influence on Mangdechhu’s operations.  Geography of the dam and intake site is a box-shaped narrow gorge (Photo 1). The bedrock on both right and left abutments seems to be Geography / Geology massive. Quartzite and mica-schist are observed along the road, which runs at a higher elevation near the dam site.  The dam site would suit a less than 100m class of arch or concrete gravity type dam in view of the morphological and geological conditions. However, since several landslide-prone slopes are observed at the reservoir areas, some protection measures should be taken to ensure safety during the construction and operation stages.  The area just upstream of the dam site, where there is a confluent point with a tributary from the left bank, could serve as a quarry site for dam construction material.

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Waterway  The right bank of the Mangdechhu is designated as a multiple zone of Jigme Singye National Park. In order to avoid impacts on the National Park, the waterway is selected to be on the left bank of the river.  The original plan for the outlet was for it to be located at the bottom of the collapsed slope. The surge tank, powerhouse and outlet were planned to be in the corridor of the National Park. Accordingly, the waterway length was slightly extended; the outlet is located at the confluence point with the tributary, and the surge tank and powerhouse are shifted.  Massive rocks such as quartzite and schist seem to be distributed along the headrace tunnel. The rock classification along most of the headrace tunnel is estimated to be mainly Class-III and the RMR value is estimated to be 58.

Powerhouse  Phyllite is expected to dominate the area surrounding the original powerhouse cavern. A massive outcrop of biotite-garnet phyllite is observed above the powerhouse site (Photo 3). Though no particular exfoliation is observed there, the rock hardness is “R3; medium strong2” and it has joints with 0.3m intervals.  Powerhouse should be shifted to the confluence point and changed to an open-air type. In line with this, the turbine type should also be changed to Pelton.

Natural Park / Protected  The right bank of the intake and power plant areas are in the Multiple- Area use zone of Jigme Singye Wangchuk National Park.  About half of the waterway (underground) goes through a biological corridor (TNP-JSWNP-RMNP, left bank of the river).

Prosperous fauna / flora  The area of the intake and waterway is covered mainly by Warm Broad-leaved Forest. Some Chir Pine Forest is observed. The outlet area is covered by Subtropical Broad-leaved Forest.  According to a park ranger of Jigme Singye Wangchuk National Park (Trongsa Office), Gee’s Golden Langur (VU) and Sambar (VU) are present in the project area, and White-bellied Heron (CR) and Rufous- necked Hornbill (VU) come to the area for feeding. Putitor (Golden) Mahseer (EN) may be present in the area. Cycas pectinata (VU), a plant species, is present in the area. White-bellied Heron is observed

Natural / Social Environment regularly along the river. One was observed at about 200 m downstream of the outlet site in 2015 by a Forestry Officer of the Zhemgang Territorial Forest Office. See the report on M18 Burgangchhu for information regarding the White-bellied Heron.

2 Cannot be scraped or peeled with a pocket knife. Hand-held specimens can be fractured with single firm blow of a geological hammer.

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Resettlement / According to the GIS data from NLC, the Google Earth map, and an Compensatory assets interview with Langtel Gewog,

 There are some houses in the reservoir area; however, they are a temporary camp for Mangdechu Hydropower Authority (MHPA). No resettlement of permanent residents is required.  Acquisition of about 9.6 acres of private agricultural and fallow land is required.  2 bridges and part of a Dzongkhag road are to be submerged under the reservoir.

 No resettlement or private land affected.

Historical / Cultural  According to the GIS data from NLC and interview with Langthel Heritage Gewog, no cultural heritage is found in the project site.

Other  Waterway passes through private residential, agricultural, fallow, and dairy farm land.

 According to the Gewog, communities in part of Langthel Gewog are in a relatively impoverished area in Trongsa Dzongkhag. Communities called “Monpa” inside Jigme Singye Wangchuk National Park (JSWNP), which includes indigenous people and is located on the right-hand side of the Mangdechhu, are in relatively impoverished areas.  On the right-hand side of the Mangdechhu, on the opposite side of the waterway on the left-hand side of the river, there are 4 Monpa communities inside the JSWNP (right-hand side of the river). However, they are not directly affected by the project in terms of land acquisition, resettlement, asset loss, or livelihood activities.

 From the experience of Mandechhu hydropower project, officials at the Dzongkhag mentioned that there are serious concerns and fears that the development of HP and associated infrastructure is causing stress on the Dzong and on other assets in the town due to all the explosions and vibrations caused by construction.

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Powerhouse

Photo 1 Dam Site Photo 2 Powerhouse and Penstock

Photo 3 Outcrops above Powerhouse Site

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Figure A 1-44 Plot Plan (M-11_Rev)

Pzm

Pzc

Figure A 1-45 Longitudinal Profile (M-11_Rev)

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1.23 M-17: Buli

Project Name M-17: Buli Date 22/11/2018 Basin Mangdechhu Tributary Burgangchhu Dam (Weir) Latitude: 27° 9' 7.30" N Longitude: 90° 47' 31.47" E

Powerhouse Latitude: 27° 7' 44.68" N Longitude: 90° 47' 17.75" E Type ROR RBL at Dam EL 1,375 m Installed Dam/Weir 69 MW 5 m Capacity Height

Primary Data Max. 14.0 m3/s Salient Crest Length 30 m General Discharge Features Features Effective Waterway 572 m 5,090 m Head Length Catchment Live Storage 214 km2 MCM Area Capacity Elongation from Dam site: 0.5km to the weir site Existing Road (improvement of 3km-long existing road from Buli Village is required) Powerhouse Site: 2 km to the outlet site from Nyekhar Village

Access (improvement of 14km-long existing road from Buli Village is required)

General Geology Geofacies (compiled by Long et al., 2011) are as follows: Subsurface geology of the project area belongs to the Orthogneiss unit (GHlo) from the Cambrian to the Ordovician Period in the Structurally- lower Greater Himalayan section of the Greater Himalayan Zone in the Neoproterozoic-Ordovician [?] period. Cliff-forming, massive-weathering, granite-composition orthogneiss; generally, exhibits leucosomes and abundant feldspar augen. Paragneiss, schist, and quartzite intervals locally split out. Interpreted as deformed Cambrian-Ordovician granite plutons that intruded Greater Himalayan sedimentary protoliths thickens toward eastern Bhutan.

 This scheme discharges the water just upstream of the Burgangchhu intake site. Therefore, a composite scheme such as a combined scheme or cascade scheme can also be considered.

Weir / Intake  At the original intake site, massive outcrops of Gneiss were observed. It seems that there are no major concerns regarding construction of Geography / Geology the intake or waterway. However, the desilting chamber must be installed underground, since there is no space suitable for a ground surface-type desilting pond.  A site 1.5km upstream was selected for the revised intake site. Since there is flat land, a ground surface-type desilting pond can be installed. Furthermore, about 70m of additional water head can be obtained in comparison with the original plan.  Geography surrounding the intake weir and intake site is gentle, and the ground surface is covered by gravel and clayey soil sedimentation caused by past debris flows.

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Waterway  While the original layout was simple, the revised layout requires a change from open channel to pressure tunnel downstream of the desilting pond.  Fresh and massive gneiss bedrock is expected through the headrace tunnel. The rock classification along the headrace tunnel is estimated to be mainly Class-II, for which the RMR value is estimated to be 62.  Nearly vertical joints (N12W/75NE) perpendicular to the stratigraphic boundary, for which the interval is around 10 to 20m, are observed on the steep cliff on the right bank of the Burgangchhu. There is concern that such joints may cause sudden springs during tunnel excavation.  Three lineaments are observed on the headrace tunnel. Two of them are E-W trend lines and one of them is a N-S trend line.

Powerhouse  An underground powerhouse is planned, since the topography is steep.  Since the geology of the area consists of massive gneiss, there are no particular issues concerning construction of an underground powerhouse and tailrace tunnel.

Natural Park / Protected  The project area is outside of the protected area. Area Prosperous fauna / flora  The area of the intake is covered mainly by Subtropical Broad-leaved Forest. The waterway (underground) and the outlet areas are covered with Subtropical Broad-Leaved and Chir Pine Forests.  According to a villager at Buli, there are Tiger (EN), Leopard (VU) and otters (species unknown) in the area. Groups of Gee’s Golden Langur (VU) were observed during the site survey (22 Nov. 2018).

Resettlement / According to the GIS data from NLC and interview with Nangkhor Gewog, Compensatory assets  No resettlement is required.  No private land acquisition is required.

Historical / Cultural  According to the GIS data from NLC and interview with Nangkhor Heritage Gewog, no cultural heritage is directly affected by the project. The Project site is located far from the village of Buli; however, it should be noted that the village has obtained Heritage Village status and also located within the village are an identified heritage forest site and other sites.

Other  Waterway passes through part of uncultivated private land.  At present, Buli in Nangkhor Gewog is relatively better off within the Dzongkhag. Natural / Social Environment  Tourism development with Eco-trails (junction of Zhemgang town - Buli village, Tali - Buli Village) is being planned under the 12th Five Year Plan (2018-2023) by the Gewog.

 According to the Dzongrab (Deputy Dzongkhag Administrator), the Dzongkhag Administration is not very keen on Hydropower Development, stating that Zhemgang is the last remaining ecological hotspot in the country and HP development might impact this ecological zone.  The Gewog welcomes and supports the project.

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Photo 1 Intake Weir Site Photo 2 Riverbed Materials at Weir Site

Photo 3 Surge Tank Site Photo 4 Powerhouse Site

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Figure A 1-46 Plot Plan (M-17)

Figure A 1-47 Longitudinal Profile (M-17)

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1.24 M-18: Nyekhar

Project 22/11/2018 M-18: Nyekhar Date Name 24/11/2018 Basin Mangdechhu Tributary Burgangchhu Dam (Weir) Latitude: 27° 7' 29.26" N Longitude: 90° 47' 42.41" E

Powerhouse Latitude: 27° 6' 11.32" N Longitude: 90° 45' 21.77" E Type ROR RBL at Dam EL 740 m

Installed Dam/Weir 43 MW 5 m Capacity Height Primary Data Max. 15.9 m3/s Salient Crest Length 30 m General Discharge Features Features Effective Waterway 399.9 m 5,229 m Head Length Catchment Live Storage 244 km2 MCM Area Capacity

Elongation from Dam site: 2 km to the outlet site from Nyekhar Village Existing Road (improvement of 14km-long existing road from Buli Village is required)

Access Powerhouse Site: 1 bridge and 0 km

General Geology Geofacies (compiled by Long et al., 2011) are as follows: Subsurface geology of the project area belongs to the Orthogneiss unit (GHlo) from the Cambrian to the Ordovician Period in the Structurally-lower Greater Himalayan section of the Greater Himalayan Zone in the Neoproterozoic-Ordovician [?] period. Cliff-forming, massive-weathering, granite-composition orthogneiss; generally, exhibits leucosomes and abundant feldspar augen. Paragneiss, schist, and quartzite intervals locally split out. Interpreted as deformed Cambrian-Ordovician granite plutons that intruded Greater Himalayan sedimentary protoliths thickens toward eastern Bhutan.

Weir / Intake  The intake site is located just downstream of the outlet for the Buli project.  As an alternative plan, the headrace could be directly connected with the tailrace of the Buli project, since the difference in the designed discharge of the two projects is just 1m3/s. In order to avoid the influence of operation stoppage for one project, additional structures such as a connecting chamber, outlet and intake would be required.  There are no particular issues surrounding the weir and intake site.

Geography / Geology Waterway  The waterway route is planned to be on the right bank of Burgangchhu. Although the left bank route can obtain 30m of additional head, its outlet is located 1.9km downstream, where a corridor of the National Park is designated.  Since the penstock is planned to be underground along the ridge, where the terrain is a gentle slope of about 30 degrees, a ground surface type is applicable.  Fresh and massive gneiss bedrock is expected through the headrace tunnel. The rock classification along the headrace tunnel is estimated to be mainly Class-II, for which the RMR value is estimated to be 66.

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Powerhouse  Underground powerhouse is planned, since there is no flat plain in the area.  Since the geology of the area consists of massive gneiss, the conditions seem to be suitable for excavation of the powerhouse cavern and tailrace tunnel.

Natural Park / Protected  The project area is outside the protected area. Area  The outlet is located on the left bank of Mangdechhu. Mangdechhu is on the border of the Multiple-use Zone (proposed) of Royal Manas National Park.

Prosperous fauna / flora  The project area is covered mainly by Subtropical Broad-leaved Forest. Some Chir Pine Forest is observed at the outlet area.  According to a park ranger of Jigme Singye Wangchuk National Park (office at Tingtibi), Chinese Pangolin (CR) is present in the project area. Putitor (Golden) Mahseer (EN) and Snow Trout (VU) are present in the area.  White-bellied Heron (CR) is present in the area, based on an interview at the Park Office at Tingtibi on 24 Nov. 2018.  The Park Office at Tingtibi monitors the activities of herons.  One pair has been breeding since 2014. The records from 2015 to 2018 are given as follows: 2 chicks in 2015, 2 in 2016, 3 in 2017, and 3 in 2018. Their nest had been recorded as being along Bertichhu, a tributary of Mangdechhu, about 5 km from Tingtibi. In 2018, they nested about 500 m upstream of the outlet for the project (left bank of Mangdechhu).  The heron feeds along Mangdechhu in winter when the water flow decreases, and along the tributaries in summer. It seems that they feed on Snow Trout and other fish.  The heron is sensitive to human activities. At about 150 m or less distance from a human, they fly away. Illegal fishing disturbs their feeding behavior and the herons sometimes feed at night, which causes them to

Natural / Social Environment collide with transmission (or distribution) lines.  There was a carcass of a young heron at the Park Office at Tingtibi. According to the Park Ranger, they collected it under a transmission line 5 days before. The cause of death is unknown, but it seems that the heron collided with a transmission line.  They do not like dusty and/or noisy areas.  The project at Burgangchhu may cause significant impact on the species. Special attention is also needed with regard to the project at Wangdigang.

Resettlement /  According to the GIS data from NLC and interview with Nangkhor Compensatory assets Gewog, No resettlement is required.  No private land acquisition is required.

Historical / Cultural  According to the GIS data from NLC and interview with Nangkhor Heritage Gewog, no cultural heritage is affected by the project.

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Other  Waterway passes through part of cultivated land and also may disturb an irrigation channel.

 Nyakhar and Tsheldang communities in Nangkhor Gewog are more economically vulnerable in comparison to other communities in the gewog and would benefit due to the project,

 According to the Dzongrab (Deputy Dzongkhag Administrator), the Dzongkhag Administration is not very keen on Hydropower Development, stating that Zhemgang is the last remaining ecological hotspot in the country and HP development might impact this ecological zone.  The Gewog welcomes and supports the project.

Photo 1 Intake Weir Site Photo 2 Intake Weir Site (Bird’s-eye View)

Photo 3 Powerhouse and Penstock Site Photo 4 Massive Gneiss exposed at the opposite side of Powerhouse Site

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Figure A 1-48 Plot Plan (M-18)

Figure A 1-49 Longitudinal Profile (M-18)

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1.25 C-7: Chamkharchhu-Ⅳ

Project Name C-7: Chamkharchhu-Ⅳ Date 26/11/2018 Basin Chamkharchhu Tributary Chamkharchhu Dam (Weir) Latitude: 27° 28' 48.18" N Longitude: 90° 48' 39.66" E

Powerhouse Latitude: 27° 24' 31.22" N Longitude: 90° 52' 58.04" E Type Pondage RBL at Dam EL 2,478 m Installed Dam/Weir 451 MW 118 (40) m Capacity Height

Primary Data Max. 130.7 m3/s Salient Crest Length 160 m General Discharge Features Features Effective Waterway 399.9 m 11,759 m Head Length Catchment Live Storage 2,080 km2 22.7 MCM Area Capacity Elongation from 1.0 hour by car from Bumthang to Dam Site Existing Road Dam Site: 0 km, Existing road 10km long is to be relocated Access Powerhouse Site: 1 bridge and 10 km

River Flow Rate 40 – 50 m3/s (Eye Measurement)

Hydrology Sediment 0.1 – 0.5 m (Boulder) General Geology Geofacies (compiled by Long et al., 2011) are as follows: 【Dam】 The subsurface geology of the project area belongs to the Upper metasedimentary unit in the Structurally-lower Greater Himalayan section in the Greater Himalayan Zone of Neoproterozoic-Ordovician [?] period. Variable metamorphic grades; dominantly amphibolite facies (Gansser, 1983),

partial melt- and often kyanite-, sillimanite-, or staurolite-bearing paragneiss, schist, and quartzite in the east (Grujic et al., 2002) and near the base in west- central Bhutan, and melt-free, dominantly upper greenschist-facies (Gansser, 1983) quartzite and biotite-muscovite-garnet schist in central Bhutan (Long and McQuarrie, 2010).

【Waterway ~ Powerhouse】 The subsurface geology of the project area belongs to the Chekha Formation in Geography / Geology the Tethyan Himalayan Zone of the Ordovician or younger period. Tan to gray, thick-bedded, fine- to medium-grained, cliff-forming, micaceous quartzite, interbedded with biotite-muscovite-garnet schist in eastern and central Bhutan (Tangri and Pande, 1995; Long and McQuarrie, 2010). Interbedded with green to white, thin-bedded marble in Dang Chu klippe. Dominated by tan, cliff- forming marble, with lesser gray phyllite and dark-gray phyllitic quartzite in Lingshi region (Gansser, 1983). Dominantly upper greenschist facies (Gansser,

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1983). 2.2-4.0 km-thick (Long et al., 2011B).

 No geographic problems which imply a landslide and/or mass rock creeping were observed during the site reconnaissance.  In general, the topography of the left bank of Chamkharchhu is steep and forms a steep cliff, whereas the terrain on the right bank side forms a gentle slope.  No clear lineaments were verified.  The geologies identified on the cut slope of the roads are mainly Gneiss.  Terrace plains were verified in places along the Chamkharchhu.

Dam / Intake  The terrain around the dam site forms a steep cliff on both banks (Photo 1).  Very hard rock of Gneiss is distributed (Photos 2 and 3).  The overall geological structure is NW-SE strike and 20SW dip.  Joints are prominent, and the three directions of N60E / 20SW (same as structure), NS / 70W and EW / 80S are remarkable.  A lot of open cracks were observed, and looseness is considerable on the whole (Photo 4).  The joints of the N60E / 20SW, which is the downstream direction, are densely prominent in some places (Photo 5).  The sedimentation volume of the riverbed is assumed to be small in general (Photos 6 and 7).

Waterway  The topography of the left bank along the waterway is steep in general (Photo 8).  Geology along the waterway route seems to be Gneiss through observation from the right bank.  Long’s Geological map shows that a thrust fault is distributed in the central part of the waterway, but clear ones were not verified. Distribution of Phylite was not identified either.  RMR evaluation point marks 72 and the rock classification is mainly Class-II.

Powerhouse Observed with drone  The ridges of the ground surface of the powerhouse are generally uniformly inclined and unstable conditions were not observed (Photos 9 and 10).

Natural Park /  The project area is outside the protected area, but the right side 1,500m Protected Area downstream from the dam to the powerhouse site is adjacent to the protected area of Phrumsengla National Park.

Prosperous fauna /  Dam site is greatly covered by cool broad leaf forest associated with dominant

flora Rhododendron and Acer species. The powerhouse site is covered with mixed Cool broad leaf forest and Warm broad leaf forest associated with Castanopsis hystrix and Oak.  The endangered species of Black necked crane (VU), Rufous necked hornbill (VU), Chestnut breasted partridge (VU), Red Panda (EN), Himalayan Muskdeer (EN), and Tiger (EN) were confirmed in the forest near the Dam and powerhouse (interview with forest office staff).

Resettlement / Compensatory assets  Four temporary structures for a sawmill on the right bank of Khagangchhu

Natural / Social Environment will be inundated (Chumey Gewog). Cultivated land of Chhokor Gewog (within the municipal area) will also be inundated.

 There seems a settlement near the PH under Ura Gewog. Local people take cows to the PH site. (This cannot be confirmed as the site is inaccessible.)

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Historical / Cultural  There is a cliff worshipped by local people where Chamkharchhu and Heritage Khagangchhu meet at the dam site. The holy place, named "sengye namsumgi dra", is sacred and reserved for national treasure. Besides the cliff, there is a small chorten that will be inundated. According to the Department of Culture (DOC), the cliff is a sacred cultural place of national importance.  There are nine historical and cultural sites around the reservoir, such as those related to the monarchy, chorten and lhakhang. Other  Chumey Gewog Office will welcome the project only if local people are not against the plan for the holy cliff.  Ura Gewog officers mentioned that local people might prefer substitute land, if there is any, from the PH site to Gewog center.

 The existing road and bridge will be submerged, which will impact the neighboring villages.

 According to the Bumthang Dzongkhag, it is included as a flood area in the flood hazard map and they will soon clear all the flood areas based on the map. The whole process, however, depends on budgets in the coming years.

Other (Special Note)  Dzongkhag Officials informed us that there are 108 glacier lakes in the upstream area. An early warning system for GLOF is in place.

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Right Left

Photo 1 Dam Site Photo 2 Gneiss (Right Bank)

Photo 4 Loosened and opened Cracks (Left Bank)

Photo 3 Gneiss (Left Bank) Photo 5 Joints Prominent Zone declined to Downstream

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Photo 6 Riverbed at Dam Site

Photo 7 Riverbed upstream of Dam

Photo 8 Waterway Route (from Right Bank)

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Photo 9 Powerhouse Site (from Right Bank)

Photo 10 Powerhouse Site (from Left Bank)

Photo 11 Terrace Plain on Right Bank

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A 1-1 Plot Plan (C-7)

A 1-2 Longitudinal Profile (C-7)

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1.26 C-10: Chamkharchhu-II

Project Name C-10: Chamkharchhu-II Date 21/11/2018 Basin Mangdechhu Tributary Chamkharchhu Dam (Weir) Latitude: 27° 16' 24.05" N Longitude: 90° 55' 46.22" E

Powerhouse Latitude: 27° 12' 8.26" N Longitude: 90° 56' 49.74" E Type ROR＋Pond RBL at Dam EL 1,225 m Installed Dam/Weir 414MW 84 (24) m Capacity Height

Primary Data Max. 130.4 m3/s Salient Crest Length 180 m General Discharge Features Features Effective Waterway 368.3 m 9,541 m Head Length Catchment Live Storage 2,525 km2 1.2 MCM Area Capacity Elongation from Existing Dam site: 10km from the powerhouse site, accessible by the local forest Road road, but its improvement is required. Powerhouse Site: Accessible by the existing road, 25km from Buli village.

Access (improvement of 25km-long existing road is required)

General Geology Geofacies (compiled by Long et al., 2011) are as follows: Subsurface geology of the project area belongs to the Orthogneiss unit (GHlo) from the Cambrian to Ordovician Period in the Structurally- lower Greater Himalayan section of the Greater Himalayan Zone in the Neoproterozoic-Ordovician [?] period. Cliff-forming, massive-weathering, granite-composition orthogneiss; generally, exhibits leucosomes and abundant feldspar augen. Paragneiss, schist, and quartzite intervals locally split out. Interpreted as deformed Cambrian-Ordovician granite plutons that intruded Greater Himalayan

sedimentary protoliths thickens toward eastern Bhutan.

 There are several gentle slopes every 2km which are inclined to the north on the left bank. Their inclination is around 25 degrees and they are homologized to the stratigraphy of this area (Questa). These gentle slopes are utilized for cultivation lands and settlements.

Geography / Geology Dam / Intake  Although the dam site could not be seen during the first site visit, it is recommended to shift it 0.3km downstream from the original site judging from observation of the surrounding areas and Google Earth (Photo 1).  Since the topography of the dam site is steep and V-shaped, a concrete gravity dam is recommended. The construction material may be obtained easily from 1 km upstream of the dam site.  Since there is a trace of a past landslide just upstream of the dam, the intake should be laid out near the dam (Photo 2).

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Waterway  The waterway route was shifted from the right bank to the left bank of Chamkharchhu, since the right bank of the project site is covered by a forest reserve. In addition, it is easier to access the headrace tunnel on the left bank.  Stratified gneissoid outcrops were observed on the left bank of Chamkharchhu with Moderately Weathered (MW) condition. The rock classification along the headrace tunnel is estimated to be mainly Class-II, for which the RMR value is estimated to be 63. Since there are long discontinuities along the stratigraphic boundary, fillings or pores might be encountered at some shallow overburden sections of the headrace tunnel.

Powerhouse  Topography of ground surface above the powerhouse site is terrace- like flat land and the depth of the powerhouse cavern is around 200m. Moderately weathered rock outcrops are readily observed. Bedrock conditions of the underground powerhouse cavern are expected to be fresh and massive, but long discontinuities might repeatedly exist every 30 to 50 meters and be gently inclined to the upstream.

Natural Park / Protected  The project area is outside the protected area. Area  Since about half of the waterway (underground) in the original layout was in a biological corridor (TNP-JSWNP-RMNP, right bank of the river), the layout was revised so as not to affect this.

Prosperous fauna / flora  The area of the intake and waterway is covered by Warm Broad- leaved Forest (confirmed via Google Earth). The outlet area is

covered by Subtropical Broad-leaved Forest.  According to a villager from Nimshong, a village nearby, Tiger (EN), Leopard (VU), and Putitor Golden Mahseer (EN) occur in the project area.  The existing roads to the project area need to be improved and widened, which will impact the forest along the roads. The one from Tingtibi to the area via Buli is about 50 km, but the distance of the one from Panbang is unknown.

Resettlement / According to the GIS data from NLC and interview with Singkhor Gewog,

Natural / Social Environment Compensatory assets and village representatives (Tshopas),  No resettlement is required.  No private land acquisition is required.

Historical / Cultural  According to NLC’s GIS data on heritage sites and an interview with Heritage the Gewog and Tshogpas at the project site, no cultural heritage is directly affected by the dam site or the powerhouse.

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Other  Waterway on the left bank runs under villages and agricultural land.

 Positive impacts on access to education and health facilities can be expected due to improvement of roads via the project since the villages near the dam and powerhouse area are connected only by farm road.

 According to the Dzongrab (Deputy Dzongkhag Administrator), the Dzongkhag Administration is not very keen on Hydropower Development, stating that Zhemgang is the last remaining ecological hotspot in the country and HP development might impact this ecological zone.  Dzongkhag officer also addressed concerns about the expectation of villagers in the Chamkharchhu area caused by the preliminary survey for the project, since in the past, even before project commencement they constructed guest houses.  The Gewog expects the project to progress.

Photo 1 Gneissoid Outcrops observed on Left Bank Photo 2 Dam and Intake Site

Photo 3 Surge Tank Site Photo 4 Outlet Site

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Figure A 1-50 Plot Plan (C-10)

Figure A 1-51 Longitudinal Profile (C-10)

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1.27 K-13: Minjey_Rev

Project Name K-13: Minjey_Rev Date 28/11/2018 Basin Kurichhu Tributary Kurichhu Dam (Weir) Latitude: 27° 34' 57.56" N Longitude: 91° 12' 38.74" E

Powerhouse Latitude: 27° 31' 3.84" N Longitude: 91° 10' 25.40" E Type Pondage RBL at Dam EL 1,070 m Installed Dam/Weir 673 MW 120 (15) m Capacity Height

Primary Data Max. 381.5 m3/s Salient Crest Length 220 m Genera Discharge Features Features Effective Waterway 204.6 m 8,908 m Head Length Catchment Live Storage 8,926 km2 52.2 MCM Area Capacity Elongation from Existing road 5km long and 1 bridge are to be relocated. Existing Road Dam site: 0 km Access Powerhouse Site: 1 bridge and 0.5 km

River Flow Rate 100 – 120 m3/s (Eye Measurement)

Hydrology Sediment 0.3 – 1.0 m Boulder General Geology Geofacies (compiled by Long et al., 2011) are as follows: 【Dam ~ Powerhouse】 The subsurface geology of the project area belongs to the Daling Formation (pCd) in the Daling-Shumar Group in the Lesser Himalayan Zone of the Paleoproterozoic period. Similar lithologies to Shumar Formation, but dominated by schist and phyllite. Quartzite is thin- to medium-bedded, and medium-gray limestone interbeds are rare. Lower contact is gradational with Shumar Formation (McQuarrie et al., 2008; Long et al., 2011A). Between 2.3 and 3.2 km-thick (Long et al., 2011A).

【Reservoir】 The subsurface geology of the project area belongs to the Jaishidanda Formation (Pzj) in the Lesser Himalayan Zone of the Neoproterozoic- Ordovician [?] period. Gray, biotite-rich, locally garnet-bearing schist, interbedded with gray to tan, biotite lamination-bearing, lithic clast-rich quartzite (Bhargava, 1995; Dasgupta, 1995; Long et al., 2011A). Typically 600-900 m-thick,

Geography / Geology but 1,700 m-thick along Kuri (Long et al., 2011A). Upper greenschist to lower amphibolite facies (Gansser, 1983).

 No geographic problems which imply a landslide and/or mass rock creeping were observed during the site reconnaissance.  In general, the topography of the right bank side is steep and forms a steep cliff, whereas the terrain on the left bank side forms a gentle uniform slope of 40 - 50°.  Clear lineaments were not observed.  The geology observed at the cut slope of the road is Schist and Gneiss.  According to Long’s geological map, MCT will be distributed in the reservoir area, but no outcrops were observed. However, the number of outcrops is small and there are places where the topography

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becomes relatively gentler than the surroundings, and MCT may pass through such areas (Photo 1).

Dam / Intake  The topography of the right bank of the Dam site forms a steep cliff (Photo 2, 3). The terrain on the left bank is uniformly inclined steeply from 40° to 50° (Photo 5).  The geology is hard schist (Photo 4).  There are a few outcrops on the left bank. The fissures of the outcrops are opened and outcrops are loosened (Photo 4). Additionally, there is a possibility that unconsolidated deposits are thickly distributed on the left bank side compared to the right bank (Photos 5 and 6).  The geological structure is EW strike and it is inclined 20~30° to the north.  Sediment volume in the riverbed is assumed to be small in general (Photo 7). (Construction materials have not been verified.)  It is assumed that the MCT will pass through the reservoir area. A large moving rock-like terrain that can be seen on the left bank side has the possibility of being the distribution area of MCT (Photo 1).

Waterway  The terrain on the right bank side along the waterway route forms a generally steep slope. Unstable slope conditions such as landslides and mass rock creeping were not observed (Photos 8 and 9).  It is assumed that the geology is mainly Quartzite and that Schist intervenes in some places.  Judging by Long’s geological map, it is considered that the waterway will become closer to the MCT distributed along Kurichhu. However, the distribution of MCT has not been observed.  RMR evaluation point marks 63 and the rock classification is mainly Class-II.

Powerhouse Observed with drone  The ridge that the powerhouse is planned to be located on is generally uniformly inclined and no unstable slope conditions, such as mass rock creeping, were observed (Photo 10).

Natural Park / Protected  Dam Site and PH are located in a Corridor. Waterway crosses the Area underground of the Corridor.

Prosperous fauna / flora  The Dam site is covered with Chir pine forest associated with Cycas pectinate, Woodfordia fruticosa. However these trees will not be

submerged as the high water level is under the tree zone.  The corridor presumed to be submerged is covered with chir pine and shrubs composed of Quercus, growing in the flank of the river.  In terms of the main endangered species designated by IUCN, according to interview with forest officers, Leopard (VU), Tiger (EN) and Rufous-necked Hornbill (VU) have been confirmed at the project site.  Migration of Golden Mahseer (EN) has not been confirmed, as the existing Dam (Kurichhu) located downstream blocked its migration (interview with park office).

Natural / Social Environment Resettlement / Compensatory assets  30 acres of private land (paddy field, corporation land and residential land with 17 private house plots, livestock yard and automobile garage) may be inundated. The elevation should be checked.  N/A

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Historical / Cultural  One chorten on the highway may be inundated. There are a holy cave Heritage named “Amdrangchu Zham”, visited by a guru, coetens and praywheels in the vicinity.

Other  The current existing Corridor will be abolished in the new management plan for protected areas as this current Corridor no longer plays a role in animal transit because the main part of the Corridor has been developed for housing sites or farmland (interview with park office).

 Gup of Minjey Gewog is for the project. Although the project affected people may not welcome it the rest of the local people will agree to the proposals for the project.

 Local people are better off than the Dzongkhag average. Employment opportunities, and enhancement of local trade and business are expected through the project’s implementation.

 Other than private land, according to GIS data, there are land areas owned by religious institutions (0.37ac), unknown (0.26ac), institutional land (0.1ac) and government institutions (orange orchards) (1.9ac) in the inundated area.  They already have good road connectivity. Negative impacts will be caused on the highway, farm roads and bridges due to the project’s implementation.

 Road maintenance for existing farm roads and water supply scheme for the chiwogs are included in the 12th 5 year plan.

Other (Special Note)  Since an important crematorium facility is located at the end of the reservoir (Photo 11), the elevation of which is EL. 1,780, the FRL of the Dam was reduced from EL. 1820 m to EL. 1770 m.

1-127 right left bank bank

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Right bank Left bank Dam

Left bank Right bank

Photo 1 MCT Distribution Area Photo 2 Dam Site

Photo 3 Right Bank of Dam Site Photo 4 Left Bank of Dam Site (Looseness of Schist) Left bank

Photo 5 Left Bank of Dam Axis

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Photo 6 Left Bank of Dam Axis

Photo 7 Riverbed around Dam Site

Photo 8 Waterway Route (Intake Side)

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Photo 9 Waterway Route (Powerhouse Side)

Photo 10 Powerhouse Site

Photo 11 Crematorium (at Confluence for Kurichhu)

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Figure A 1-52 Plot Plan (K-13_Rev)

FSL : 1170m TWL : 950m

pCd

Figure A 1-53 Longitudinal Profile (K-13_Rev)

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1.28 K-15: Phawan

Project Name K-15: Phawan Date 28/11/2018 Basin Kurichhu Tributary Kurichhu Dam (Weir) Latitude: 27° 29' 0.53" N Longitude: 91° 10' 58.57" E

Powerhouse Latitude: 27° 28' 50.15" N Longitude: 91° 10' 50.62" E Type Pondage RBL at Dam EL 905 m Installed Dam/Weir 499 MW 185 (30) m Capacity Height

Primary Data Max. 401.2 m3/s Salient Crest Length 460 m General Discharge Features Features Effective Waterway 144.2 m 600 m Head Length Catchment Live Storage 9,388 km2 112.6 MCM Area Capacity Elongation from Dam Site: 0.5 km Existing Road Powerhouse Site: 0.5 km Access River Flow Rate 100 – 120 m3/s (Eye Measurement) Sediment 0.3 – 1.0 m Boulder

Hydrology General Geology Geofacies (compiled by Long et al., 2011) are as follows:

The subsurface geology of the project area belongs to the Shumar Formation in the Daling-Shumar Group in the Lesser Himalayan Zone of Paleoproterozoic period. Light-gray to white, tan-weathering, very fine-grained, medium- to thick- bedded, cliff-forming quartzite. Interbeds of thin to thick-bedded, green, muscovite-biotite schist and phyllite with diagnostic sigmoidal quartz vein

boudins become more common in the upper section. Between 1-2 km thick, except for 6 km-thick section local to Kuri valley (Long et al., 2011A). Upper greenschist facies (Gansser, 1983).

 No geographic problems which imply a landslide and/or mass rock creeping were observed during the site reconnaissance.  In general, the topography of the right bank side is steep and forms a

Geography / Geology steep cliff, whereas the terrain on the left bank side forms a uniform slope of 40 - 50°.  Clear lineaments were not observed.  The geology observed at the cut slope of the road is Quartzite and Schist.  According to Long’s geological map, MCT will be distributed on the right bank side upstream area in the reservoir, but no outcrops were observed. (Photo 1).

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Dam / Intake  The topography of the right bank of the Dam site forms a steep cliff (Photos 2 and 3). The terrain on the left bank is uniformly inclined steeply from 40° to 50° (Photo 2, 4).  The geology is mainly hard Quartzite and Schist intervenes in some places (Photo 5).  There are a few outcrops on the left bank and there is a possibility that unconsolidated deposits are thickly distributed (Photo 6).  Although slight folds are observed in some places, the geological structure is EW strike and it is inclined 10~20° to the north (Photo 3).  It is assumed that riverbed gravel is deeply deposited (Photo 7).

Waterway  The topography of the right bank along the waterway route forms a steep slope in general.  It is assumed from observations at the cut slope of the road that the geology is mainly hard Quartzite with Schist intervening in some places.  It is estimated that the RMR evaluation point marks 56 and the rock classification is mainly Class-III.

Powerhouse Observed with drone  The ridge that the powerhouse is planned to be located on forms a steep slope. Unstable slope conditions such as mass rock creeping were not observed (Photos 8 and 9).

Natural Park /  The project area is outside the protected area. Protected Area Prosperous fauna /  The Dam site is covered by broad-leaved trees such as Bischofia flora javanica, Trevesia palmata, and chir pine trees. Part of the Dam site (left bank) is planted with a man-made forest associated with Lebbek

tree, Scots pine and Soap-nut tree. These trees will be submerged.  In terms of the main endangered species designated by IUCN, according to interview with forest officers, Leopard (VU), Tiger (EN) and Rufous-necked Hornbill (VU) have been confirmed at the project site (interview with Park office staff).  Migration of Golden Mahseer (EN) has not been confirmed, as the existing Dam (Kurichhu-I) located downstream blocked its migration (interview with park office). / Social Environment

Resettlement /  6 acres of barren land (1), paddy field (5 partly) and orange orchard (1 Compensatory assets partly) will be inundated. Natural

Historical / Cultural  There is a holy site in the river just downstream of the reservoir area (2 Heritage golden fish stones). The Gewog plans to revive the site together with another one in Tsenkhar in the 12th 5 year plan, and requested the Tourism Council to keep the footpath as it is.

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Other  Gewog people are positive about the development.  Local people are better off than the average of Lhuntse Dzongkhag. They expect business opportunities and employment.

 A major road, including a highway, will be affected by the project’s implementation, together with 4 bridges and some portion of farm roads too.  2 MOAL facilities (poultry farm and dairy farm) will be inundated. Local species are collected from all over the country and kept at the farms. Local employment opportunities at farms will be lost due to the project’s implementation.

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Photo 1 MCT Distribution Area Photo 2 Gneiss (Right Bank)

Photo 3 Quartzite (Right Bank)

Photo 4 Left Bank of Dam Photo 5 Outcrops at Dam Axis (Quartzite) (Schist intervenes)

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Photo 6 Unconsolidated Deposits on the Left Bank Photo 7 Riverbed Gravels

Photo 8 Penstock and Powerhouse Site Photo 9 Powerhouse Site

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Figure A 1-54 Plot Plan (K-15)

Figure A 1-55 Longitudinal Profile (K-15)

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1.29 G-6: Khamdang_Rev

Project Name G-6: Khamdang_Rev Date 2/12/2018 Basin Gongri Tributary Tawangchhu Dam (Weir) Latitude： 27° 28' 48.69" N Longitude： 91° 38' 42.40" E

Powerhouse Latitude： 27° 26' 36.59" N Longitude： 91° 34' 46.32" E Type ROR+Pond RBL at Dam EL 957 m Installed Dam/Weir 512 MW 46 (13) m Capacity Height

Primary Data Max. 440.1 m3/s Salient Crest Length 150 m General Discharge Features Features Effective Waterway 134.9 m 9,652 m Head Length Catchment Live Storage 7,286 km2 0.8 MCM Area Capacity Elongation from Dam Site : 5 km Existing Road Powerhouse Site：0 km Access River Flow Rate 120 – 150 m3/s (Eye Measurement) Sediment 0.3 – 1.0 m (Boulder)

Hydrology General Geology Geofacies (compiled by Long et al.,2011) are as follows: The subsurface geology of the project area belongs to the Upper metasedimentary unit in Structurally-lower Greater Himalayan section in the Greater Himalayan Zone of Neoproterozoic-Ordovician[?] period. Variable metamorphic grades; dominantly amphibolite facies (Gansser, 1983), partial melt- and often kyanite-, sillimanite-, or staurolite-bearing paragneiss, schist, and quartzite in east (Grujic et al., 2002) and near base in west-central Bhutan, and melt-free, dominantly upper greenschist- facies (Gansser, 1983) quartzite and biotite-muscovite-garnet schist in central Bhutan (Long and McQuarrie, 2010).

 Schist and Gneiss are distributed around Powerhouse site. In consideration of Long’s geological map, the same geology is assumed to distribute in the whole project area.  According to Google Earth image, any large-scale collapse land and clear lineament are not verified in the whole project area.  There are many alluvial fans in the confluence of main river Geography / Geology and tributaries.  The upstream end of pond is located in the vicinity of the border with India.

Dam / Intake Observed with the drone  The slopes of the both banks have a uniform inclination of 40 to 50°. A land slide and/or a mass rock creeping is not observed (Photo1, 2).  The distribution of riverbed gravel is not clear. A large-scale alluvial fan is verified on the right bank about 2 km downstream of the dam (Photo 3).

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Waterway Observed with the drone  The geology along the waterway could not be verified, but if the geological condition is equivalent to that of the powerhouse site, RMR evaluation point is assumed to mark 56 and the rock classification is mainly Class-III.  Distribution of alluvial deposits was observed in the central part of the waterway, but it is judged that there is no problem if the waterway is planned avoiding the that area (Photo 4, 5).

Powerhouse  The terrain around the powerhouse site forms steep cliff. The unstable conditions of slope such as mass rock creeping were not verified (Photo 6, 7).  Very hard rock of Gneiss / Schist is distributed around Powerhouse site (Photo 8). There are few outcrops and unconsolidated deposits are thickly distributed (Photo 9).  The overall geological structure is NW-SE strike and 10 - 20NE dip. And joints of the same direction are prominent.  Penstock route and Powerhouse site was shifted slightly to the downstream, where the outcrops of very hard Gneiss / Schist were observed.

Natural Park /  The project area is outside the protected area. Protected Area  The New Protected area management plan prepared by DOFPS includes these project sites into Corridor (hearing from forest office).

Prosperous fauna /  The Dam site is covered by scattered chir pine associated with flora warm broad-leaved trees such as Sizyzium tree. These chir pine trees will not be submerged as high water level is under these tree zone, but broad-leaved trees growing river side will be submerged (supposed from distance).  Surface ground of waterway (planned in the underground) is covered with shrubs growing after forest fire at the flank of steep barren slope.  The site of Power house is located in rock area covered with shrubs scattered in bare steep slope.

Environment  As a main species designated by IUCN, according to interview with local people, Tiger (EN), Capped Langur (VU), Leopard (VU) are being confirmed at the project site.

Resettlement / Compensatory assets  Paddy field will be inundated due to the construction of Natural / Social reservoir (Manam village, Manam Chiwog of Toetsho Gewog). Mushroom, lemongrass and bamboo will be affected.  A few local people take cows down to the river around reservoir site during winter time (Toetsho Gewog).  There are some small wetlands seem to exist near the Dam site.

 N/A

Historical / Cultural  N/A Heritage

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Other  Khamdang and Toetsho gewogs officers said that local people long await and welcome HPP. Toetsho Gup also suggests to create a transit camp within Toetsho for the benefit of local people.

 There is one “nye” (holy place) located just below the proposed waterway: “Gongzala nye”, which is one of the most sacred site in the country. There is another important nye located above the waterway: “Omba Nye.” During winter season, lots of people go visit them, and the Dzongkhag has a plan to develop a trekking route between those sites for local tourists.  Manan villagers speak Dakpa language. Their annual ritual is different from the rest of Bhutan.  No road is connected to Manam village as it is at the country border. Dzongkhag Administration Office implied that there would be no plan for connecting road with Manan village.  Land substitute and cash compensation are going to be carried out for private land within the location of the planned Kholongchhu HPP colony. Proposed alternative lands (8 acres for 18 households) are in the surrounding area of proposed PH site, which has been just allotted to the 18 households.  Paddy field of Manan village is located in wetland, which government preserves. Dzongkhag officials do not want their wetland destroyed as they have limited stock of wetland in the district.

Others’ Special Note  Our site visit was not permitted by Local authority due to sensitive area near the border with India.  Penstock route and Powerhouse site was shifted slightly to the downstream, where the outcrops of very hard Gneiss / Schist were observed.

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Photo 1 Dam View from Downstream Photo 2 Dam Site

Photo 3 Alluvial Fan downstream of Dam Photo 4 Waterway Route

Photo 5 Waterway Route

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Photo 6 Penstock and Powerhouse Site

Photo 7 Outcrops around Powerhouse Shifted

Photo 8 Outcrop of Schist Photo 9 Unconsolidated Deposits

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Figure A 1-56 Plot Plan (G-6)

Figure A 1-57 Longitudinal Profile (G-6)

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1.30 G-7: Gongri_Rev

Project Name G-7: Gongri_Rev Date 3/12/2018 Basin Gongri Tributary Gongri Dam (Weir) Latitude: 27° 22' 50.27" N Longitude: 91° 33' 37.08" E

Powerhouse Latitude: 27° 21' 15.59" N Longitude: 91° 33'20.49" E Type Pondage RBL at Dam EL 722 m Installed Dam/Weir 546 MW 130 (27) m Capacity Height

Primary Data Max. 523.7 m3/s Salient Crest Length 335 m General Discharge Features Features Effective Waterway 120.9 m 3,963 m Head Length Catchment Live Storage 8,669 km2 48.2 MCM Area Capacity Elongation from Existing Road of 4km long is to be relocated. Existing Road Dam site: 0 km Access Powerhouse Site: 1 bridge and 0.3km

River Flow Rate 120 – 150 m3/s (Eye Measurement)

Hydrology Sediment 0.3 – 1.0 m (Boulder) General Geology Geofacies (compiled by Long et al., 2011) are as follows: The subsurface geology of the project area belongs to the Upper metasedimentary unit in the Structurally-lower Greater Himalayan section in

the Greater Himalayan Zone of the Neoproterozoic-Ordovician [?] period. Variable metamorphic grades; dominantly amphibolite facies (Gansser, 1983), partial melt- and often kyanite-, sillimanite-, or staurolite-bearing paragneiss, schist, and quartzite in the east (Grujic et al., 2002) and near the base in west-central Bhutan, and melt-free, dominantly upper greenschist- facies (Gansser, 1983) quartzite and biotite-muscovite-garnet schist in central Bhutan (Long and McQuarrie, 2010).

Geography / Geology  Schist and Gneiss are distributed across the whole project area.  In the Google Earth image, no large-scale collapsed land or clear lineaments were identified across the whole project area.

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Dam / Intake Observed with drone  Since thick unconsolidated sediment is distributed on the right bank around the original dam site and it is not suitable for a dam site, the dam site was shifted about 2km to the upper stream.  A steep cliff is formed on the right bank of the dam. No landslides or mass rock creeping have been observed (Photos 1, 2 and 3).  Geology around the revised Dam site is mainly Gneiss and Schist is distributed partially. Gneiss is very hard (Photo 5).  The overall geological structure is EW strike and it is inclined 20° to the south.  In the Gneiss, small shear zones have been confirmed in rare cases. They are about 10 centimeters wide, EW strike and inclined 20 degrees to the south harmoniously with the whole structure (Photo 6).  The distribution of riverbed gravel is small in scale (Photo 7). Alluvial fan deposits are widely distributed on the left bank downstream of the dam (Photo 8).

Waterway  The original waterway route was planned for the right bank side of the mountain, where unconsolidated deposits are widely distributed. Therefore, the waterway route was shifted to the left bank side.  Judging from the geological conditions of the cut slope along the right bank road, the geology along the waterway route is assumed to be Gneiss and Schist (Photo 9). The RMR evaluation point marks 70 and the rock classification is mainly Class-II.

Powerhouse Observed with drone  The terrain around the powerhouse site is generally uniformly inclined steeply from 40° to 50°, and no unstable slope conditions, such as mass rock creeping, were observed (Photo 10).  Although the original powerhouse was planned to be located in the center of a ridge, since the tip was thin the location was shifted to the Gamrichhu side (Photo 11).  The geology around the Powerhouse site is Gneiss and Schist. The unconsolidated deposits are thin (Photo 12).  The geological structure is assumed to be N30W strike and 30 - 40NE dip.

Natural Park /  The project area is outside the protected area. Protected Area Prosperous fauna /  The Dam site is covered by scattered chir pine associated with warm flora broad-leaved trees such as the Sizyzium tree. These chir pine trees will not be submerged as the high water level is under the tree zone, but broad- leaved trees growing by the riverside will be submerged.  Surface ground of the waterway (planned to be underground) is mainly covered with chir pine.  The powerhouse site is covered with scattered chir pine trees and shrubs, composed of Alnus, growing at the flank of the river.  An endangered plant species designated by the IUCN, Cycas pectinate (VU), has been confirmed near the Dam site. However, this plant will not be submerged as the high water level is under this.

Resettlement / (Further survey is required) Natural / Social Environment Compensatory assets  56 acres of paddy field and residential land with 4 settlements. Crops will be lost.

 N/A

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Historical / Cultural  Strong concern was shown by the Department of Culture (DOC) and Heritage Trashi Yangtse Dzongkhag Administration that one of the most important cultural heritage sites in Bhutan (Gom Kora and sacred river basin) may be inundated due to the project implementation. DOC recommends avoiding negative impacts on heritage of national importance, or implementing mitigation measures for this at least. Gom Kora will not be inundated according to the latest project plan, whereas the holy river basin will be.  There is also a chorten and sacred stone which will be inundated. Several heritage sites are located in the vicinity too.

Other  Local people move to urban areas such as Thimphu and Paro, where their children and relatives settle, due to the unavailability of job opportunities in the project area. Approximately 20% of houses are kept vacant although their registrations still remain.  Gewog officers expect employment opportunities created by the project implementation and income generation accordingly.  The substation currently under construction for Kholongchhu HPP may be inundated.  According to local people interviewed during the 2nd site reconnaissance in March 2019, there was no local consultation during Khlongchhu HPP’s FS. Local people inquired at the end of it and the locations of project facilities and the plan itself were reexamined in order to avoid sacred places.

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dam( Left bank

Right bank

Photo 1 Revised Dam Site

Talus Deposit

Dam Photo 2 Left Bank of Revised Dam Site

Right bank

Alluvial Fan Deposit

Photo 3 Right Bank of Revised Dam Site

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Photo 4 Outcrops along Road on Right Bank of Revised Dam Site (Gneiss)

Photo 5 Outcrops along Road on Right Bank Photo 6 Shear Zone (Gneiss)

Left bank

Photo 7 River Bed of Revised Dam Site Photo 8 Terrace and Alluvial Fan Deposit

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Photo 9 Waterway Route Photo 10 Powerhouse Area

Slim Ridge Drangmechhu

Gamrichhu

Photo 11 Powerhouse Area Photo 12 Outcrops around Powerhouse

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Figure A 1-58 Plot Plan (G-7)

GHlmu

Figure A 1-59 Longitudinal Profile (G-7_Rev)

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1.31 G-9: Gamrichhu-3

Project Name G-9: Gamrichhu-3 Date Basin Gongri Tributary Gamri Dam (Weir) Latitude: 27° 24' 47.14" N Longitude: 91° 52' 19.79" E

Powerhouse Latitude: 27° 23' 18.66" N Longitude: 91° 45' 53.01" E Type ROR RBL at Dam EL 2,280 m Installed Dam/Weir 123 MW 5 m Capacity Height

Primary Data Max. 18.4 m3/s Salient Crest Length 30 m General Discharge Features Features Waterway Effective Head 771.9 m 13,786 m Length Catchment Live Storage 214 km2 MCM Area Capacity Elongation from Existing Road Access

River Flow Rate (Eye Measurement)

Hydrology Sediment General Geology Geofacies (compiled by Long et al., 2011) are as follows:

Subsurface geology of the project area drops in the Chekha Formation (Pzc)

in the Tethyan Himalayan Zone in the Ordovician or younger period. Tan to gray, thick-bedded, fine- to medium-grained, cliff-forming, micaceous quartzite, interbedded with biotite-muscovite-garnet schist in eastern and central Bhutan. Interbedded with green to white, thin-bedded marble in Dang Chu klippe. Dominated by tan, cliff-forming marble, with lesser gray phyllite and dark-gray phyllitic quartzite in Lingshi region. Dominantly upper greenschist facies.

Geography / Geology Weir / Intake Waterway Powerhouse  Natural Park / Project site is designated as Protected Area (Sakteng Wildlife Sanctuary) Protected Area (Dam site is planned to be in the core zone, and part of the waterway passes through the underground of a Multiple-use zone and Buffer zone) Prosperous fauna /  N/A (survey was not conducted as it is in a protected Core Zone). flora Resettlement /  N/A Compensatory assets Historical / Cultural  There are two dangrim in the vicinity. Heritage Other  Implementation of any kind of project in a core zone is strictly prohibited

Natural / Social Environment in Bhutan (interview with Division of Forests and Park Services)

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Other (Special Note)  Local Government (Phongmey gewog) expects great positive impact: employment opportunities, creation of local market and non-residents' returning.

Figure A 1-60 Plot Plan (G-9)

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1.32 G-10: Gamrichhu-2_Rev2

5/12/2018 Project Name G-10: Gamrichhu-2_Rev2 Date 6/12/2018 Basin Gongri Tributary Gamri Dam (Weir) Latitude: 27° 24' 10.85" N Longitude: 91° 49' 2.74" E

Powerhouse Latitude: 27° 23' 5.69" N Longitude: 91° 43' 16.76" E Type ROR RBL at Dam EL 1,785 m

Installed Dam/Weir 108 MW 35 (10) m Capacity Height Primary Data Max. 23.7 m3/s Salient Crest Length 140 m General Discharge Features Features Effective Waterway 525.5 m 11,920 m Head Length Catchment Live Storage 307 km2 MCM Area Capacity Elongation from Dam site: 1 bridge and 1 km Existing Road Powerhouse Site: 1 km Access

River Flow Rate 10 – 12 m3/s (Eye Measurement)

Hydrology Sediment 0.3 – 1.0 m (Boulder) General Geology Geofacies (compiled by Long et al., 2011) are as follows:

Subsurface geology of the project area drops in the Chekha Formation (Pzc) in the Tethyan Himalayan Zone in the Ordovician or younger period. Tan to gray, thick-bedded, fine- to medium-grained, cliff-forming, micaceous quartzite, interbedded with biotite-muscovite-garnet schist in

eastern and central Bhutan. Interbedded with green to white, thin-bedded marble in Dang Chu klippe. Dominated by tan, cliff-forming marble, with lesser gray phyllite and dark-gray phyllitic quartzite in Lingshi region. Dominantly upper greenschist facies.

 The site is planned to be on the right bank of Gamrichhu, flowing from the east to the west. The left bank of Gamrichhu is gently sloping and the

Geography / Geology right bank, steeply inclined. In the Google Earth image, no large-scale collapsed land or clear lineaments were identified across the whole project area.  Gneiss, Schist and Quartzite are distributed across the whole project area.  A lot of boulders are distributed on the scale of several meters in the riverbed, and it was apparent that debris flow had occurred frequently.

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Dam / Intake Observed with drone  Since the slopes on both banks of the dam axis are covered by vegetation, Geological conditions are unknown. However, in the drone image, it seems that both banks have a small cliff topography with a slope of about 30 to 40° (Photos 1 and 2).  Geology around Dam site is assumed to be Schist, judging from the outcrop of the left bank upstream of the dam (Photo 3).  The upper slope of the dam on the right bank is dotted with boulders of Gneiss. There is a possibility that collapsed sediment from the steep cliff behind has accumulated thickly.  The geological structure is EW strike and it is inclined 10 - 20° to the north.  A lot of boulders are distributed on the scale of several meters in the riverbed, and it is apparent that debris flow will occur frequently (Photo 4).

Waterway  The waterway route was revised from the left bank side to the right bank side, where a steep cliff has formed.  Judging from outcrops along the right bank road, the geology along the waterway route is assumed to be Gneiss, Schist and Quartzite. Hydrothermal alterations are observed along the road in places (Photos 5, 6 and 7).  Judging from outcrops along the right bank road, the RMR evaluation point marks 59 and the rock classification is mainly Class-III.

Powerhouse Observed with drone  The terrain around the powerhouse site forms a steep cliff. No unstable slope conditions such as mass rock creeping were verified (Photo 8).  The geology around the Powerhouse site seems to be very hard Quartzite and Schist (Photo 9).  The geological structure is EW strike and it is inclined 30 - 40°to the north.

Natural Park /  Site is not designated as a Protected Area but about 600m upstream from Protected Area the dam site is the Protected Area of Sakteng Wildlife Sanctuary. Prosperous fauna /  The Dam site is mainly covered with cool broad-leaved forest associated flora with Oak, Cherry and conifer of chir pine. These trees will not all be submerged but some growing at the flank of the river will be submerged

as the high water level is limited to under the lower flank.  Surface ground of waterway (planned to be underground) is covered with scattered chir pine growing at the flank of a steep barren slope.  The powerhouse site is covered with shrubs composed of Dhus sp., Alnus, growing at the flank of the river.  In terms of the main endangered species designated by the IUCN, according to interviews with local people, Tiger (EN), Capped Langur (VU) and Otter (name of species unknown) have been confirmed at the project site.  Migration of fish has not been confirmed (results of interview with local people). Natural / Social Environment

Resettlement /  N/A Compensatory assets Historical / Cultural  There are two choetens in the vicinity of the project site. Heritage

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Other  Gewog officers expect great positive impact, such as employment opportunities and the creation of a local market, and they expect people who have migrated out of the villages to return home.

Other (Special Note)  By changing the dam site to the upper stream and changing the waterway route from the left bank side, where the slope is gentle and there are many paddy fields, to the right bank side, concern about the waterway route runs into movement clods was eliminated.

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Right bank Left bank

Photo 1 Dam Site

Left bank

Right bank

Photo 2 Around Dam Site leftbank

Photo 3 Outcrop upstream of Dam on Left Bank Photo 4 Riverbed (Schist)

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やせ尾根

Photo 5 Riverbed Photo 6 Outcrop along Road (Collapse due to Hydrothermal Alteration)

Photo 7 Outcrop along Road (Collapse due to Hydrothermal Alteration) (Gneiss)

Photo 8 Penstock and Powerhouse Site Photo 9 Around Powerhouse Site

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Photo 10 Riverbed around Powerhouse Photo 11 Outcrops around Powerhouse

Figure A 1-61 Plot Plan (G-10 Rev2)

（Qz）

Pzc

Figure A 1-62 Longitudinal Profile (G-10_Rev2)

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1.33 G-11: Gamrichhu-1_Rev2

5/12/2018 Project Name G-11: Gamrichhu-1_Rev2 Date 6/12/2018 Basin Gongri Tributary Gamri Dam (Weir) Latitude: 27° 22' 56.93" N Longitude: 91° 42' 5.37" E

Powerhouse Latitude: 27° 21' 1.88" N Longitude: 91° 33' 15.54" E Type ROR RBL at Dam EL 1,155 m

Installed Dam/Weir 150 MW 35 (10) m Capacity Height Primary Data Max. 38.1 m3/s Salient Crest Length 80 m General Discharge Features Features Effective Waterway 455.7 m 15,765 m Head Length Catchment Live Storage 493 km2 MCM Area Capacity

Elongation from Dam site: 1 km Existing Road Powerhouse Site: 1 km

Access

River Flow Rate 15 – 20 m3/s (Eye Measurement)

Hydrology Sediment 0.3 – 1.0 m (Gravel) General Geology Geofacies (compiled by Long et al., 2011) are as follows: 【 】 Dam ~ Waterway Subsurface geology of the project area drops in the Chekha Formation (Pzc) in the Tethyan Himalayan Zone in the Ordovician or younger period. Tan to gray, thick-bedded, fine- to medium-grained, cliff-forming, micaceous quartzite, interbedded with biotite-muscovite-garnet schist in eastern and central Bhutan. Interbedded with green to white, thin-bedded

marble in Dang Chu klippe. Dominated by tan, cliff-forming marble, with lesser gray phyllite and dark-gray phyllitic quartzite in Lingshi region. Dominantly upper greenschist facies.

Geology 【Waterway ~ Powerhouse】 The subsurface geology of the project area belongs to the Upper metasedimentary unit (GHlmu) in the Structurally-lower Greater Himalayan section in the Greater Himalayan Zone of the Neoproterozoic-Ordovician Geography / [?] period. Variable metamorphic grades; dominantly amphibolite facies (Gansser, 1983), partial melt- and often kyanite-, sillimanite-, or staurolite-bearing paragneiss, schist, and quartzite in the east (Grujic et al., 2002) and near the base in west-central Bhutan, and melt-free, dominantly upper greenschist- facies (Gansser, 1983) quartzite and biotite-muscovite-garnet schist in central Bhutan (Long and McQuarrie, 2010).

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 The site is planned to be on the right bank of Gamrichhu, flowing from the east to the west. The left bank of Gamrichhu is gently sloping and the right bank, steeply inclined. In the Google Earth image, no large-scale collapsed land or clear lineaments were identified across the whole project area.  A lot of boulders are distributed on the scale of several meters in the riverbed, and it is apparent that debris flow had occurred frequently.  Schist and Gneiss are distributed around the Powerhouse site and Waterway route. In consideration of Long’s geological map, the same geology is assumed to be distributed across the whole project area.  Waterway route may pass through a thrust fault.

Dam / Intake Observed with drone  The terrain on the right bank of the Dam site is uniformly inclined steeply from 40° to 50° and no unstable slope conditions such as landslides or mass rock creeping were observed. Since the slopes on the left banks are covered by vegetation, geological conditions are unknown. However, the terrain on the left bank seems to be inclined from 30° to 40° (Photos 1, 2 and 3).  Geology around the Dam site is assumed to be Gneiss and Schist, judging from the surrounding outcrops (Photo 4).  The geological structure is EW strike and it is inclined 20 - 30° to the north.  Distribution of riverbed gravel is unknown. However, since debris flow deposits are distributed along Gamrichhu, thick riverbed gravel is assumed (Photo 5).

Waterway  Although the geology along the Waterway could not verified, if the geological conditions are equivalent to those of the powerhouse site and the area around the road, the RMR evaluation point marks 56 and the rock classification is mainly Class-III.  Overburden depth along the waterway route becomes thinner in the upper stream area (Photo 6). There is also a concern that sediments are distributed thickly in the creek portion of the waterway route on the upstream side (Photo 5).  According to the Long’s geological map, the waterway route will cross a thrust fault. The conditions have not verified.

Powerhouse  The terrain around the powerhouse site is generally uniformly inclined steeply from 40° to 50° and unstable slope conditions such as mass rock creeping were not observed (Photos 7 and 8).  The geology around the Powerhouse site is Gneiss and Schist. The unconsolidated deposits are thin (Photo 9).  The geological structure is N30W strike and 30~40NE dip, judging from the cut slope of the road along Gongri.

 Natural Park / The project area is outside the protected area. Protected Area

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Prosperous fauna /  The Dam site is covered with shrubs composed of Dhus sp., Alnus, flora growing at the flank of the river.  Surface ground of waterway (planned to be underground) is covered with scattered chir pine growing at the flank of a steep barren slope.  The powerhouse site is covered with shrubs composed of Dhus sp., Alnus, growing at the flank of the river, and a small part of its area is cultivated for rice fields.  In terms of the main endangered species designated by the IUCN, according to interview with local people, Tiger (EN), Capped Langur (VU) and Otter (name of species unknown) have been confirmed at the project site.  Migration of fish has not been confirmed (results of interview with local people).

Resettlement / Compensatory assets  There is one empty house at the reservoir site. Local people abandoned it due to fear of wild animals, but it remains registered at the gewog. The rest of the area is covered by government barren land.

 N/A

Historical / Cultural  There is a choeten in the vicinity of the project site. Heritage Natural / Social Environment Other  Part of a cultivated rice field will be used for the powerhouse and waterway sites.  Poverty incidence is worse than the Dzongkhag average. They expect more employment opportunities, business opportunities and more local involvement.

 The river basin is being eroded year by year, and floods often hit the area. The massive flood of 2003 caused VTI to be inundated, and a bridge, houses, paddy fields and animals were washed away. They are trying gradually to relocate all the facilities from the river basin.

Other (Special Note)  By changing the dam site to the upper stream, concern about the occurrence of landslides in the reservoir area was eliminated.

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Right bank

Right bank

Dam Left bank

Left bank

Photo 1 Dam Site Photo 2 Dam Site Right bank Right bank

Left bank Left bank

Photo 3 Dam Site with a bird’s-eye View Photo 4 Outcrop at Dam Site

Deposits might be thick

Photo 5 Waterway Route (Intake side) Photo 6 Waterway Route (Outlet side)

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Drangmechhu Slim Ridge

PH Site

Gamrichhu

Photo 7 Powerhouse Site Photo 8 Outcrops around Powerhouse

Photo 9 Ground Surface around Powerhouse

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Figure A 1-63 Plot Plan (G-11_Rev2)

Pzc GHlmu

Figure A 1-64 Longitudinal Profile (G-11_Rev2)

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1.34 G-13: Sherichhu

4/12/2018 Project Name G-13: Sherichhu Date 5/12/2018 Basin Drangmechhu Tributary Sherichhu Dam (Weir) Latitude: 27° 22' 19.60" N Longitude: 91° 21' 39.77" E

Powerhouse Latitude: 27° 16' 7.25" N Longitude: 91° 24' 47.40" E Type ROR RBL at Dam EL 1,100m

Installed Dam/Weir 58 MW 5 m Capacity Height Primary Data Max. 16.8 m3/s Salient Crest Length 30 m General Discharge Features Features Effective Waterway 399.9 m 12,640 m Head Length Catchment Live Storage 278 km2 MCM Area Capacity

Elongation from Dam site: Accessible to the intake site using the existing road Existing Road (improvement of the existing road from the nearest village to the intake site)

Access Powerhouse Site: Accessible via the existing main road

River Flow Rate 7 – 8 m3/s (Eye Measurement)

Hydrology Sediment 1.0 – 3.0 m (Boulder) General Geology Geofacies (compiled by Long et al., 2011) are as follows: The subsurface geology of the project area cuts across the Shumar Formation (pCs), and Daling Formation (pCd) of the Daling-Shumar Group in the Neoproterozoic Period, Jaishidanda Formation (Pzj) in the Neoproterozoic-Ordovician [?] period, and finally the Lower metasedimentary unit (GHlml) in the Neoproterozoic-Cambrian [?] period of the Structurally-lower Greater Himalayan section in the Greater Himalayan Zone, in sequence from south to north. MCT lies between Pzj and GHlml in the middle of the waterway route. Shumar Formation (pCs), which only surrounds the powerhouse site,

consists of light-gray to white, tan-weathering, very fine-grained, medium to thick-bedded, cliff-forming quartzite. Interbeds of thin to thick-bedded, green, muscovite-biotite schist and phyllite with diagnostic sigmoidal quartz vein boudins become more common in the upper section. Daling Formation (pCd), which covers the lower-half proportion of the waterway route, has similar lithologies to the Shumar Formation but is dominated by schist and phyllite. Quartzite is thin to medium-bedded, and medium-gray limestone interbeds are rare. Lower contact is gradational Geography / Geology with the Shumar Formation. Jaishidanda Formation (Pzj), which is distributed in the upper-half of the waterway in the southern part of MCT, consists of gray, biotite-rich, locally garnet-bearing schist, interbedded with gray to tan, biotite lamination-bearing, lithic clast-rich quartzite. Its facies change from greenschist in the upper part to amphibolite in the lower part. The lower metasedimentary unit (GHlml), which is distributed only near the intake site, consists dominantly of amphibolite-facies metasedimentary rocks, including quartzite, and biotite-muscovite-garnet schist and paragneiss often exhibiting kyanite, sillimanite, or staurolite, and partial melt textures. Orthogneiss intervals locally split out.

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Weir / Intake  The topography of the intake weir site is asymmetric. The left bank’s slope inclination is almost vertical and the right bank’s is 25 degrees and covered by vegetation. The rock distributed on the steep cliff on the left abutment is gneiss. There are plenty of huge boulders around the weir site.  Although there were no concerns about the construction of the original weir site, the weir site was shifted 300m upstream so that a ground surface-type desilting basin could be constructed on the alluvium terrace on the left bank. In order to connect to the waterway to the gneiss rocks, a culvert about 50m long is required for protection from the seasonal floods from the small creek on the left bank, which has no water flow in the dry season.

Waterway  The waterway is planned to be on the left bank of Sherichhu. Although the geology of the upper stream half part of the waterway route is Gneiss, the waterway crosses MCT, which is generally a weak zone where caution is needed. Since the downstream half part of the waterway passes Schist and/or Phyllite, which has fissile features, dominant zone. Special attention should be paid during construction.  Geotechnical investigation surrounding the inferred MCT crossing zone is fundamental to examine the rock conditions.  The rock classification along the headrace tunnel is estimated to be Class-IV rock, for which the RMR value is estimated to be 34.

Powerhouse  The powerhouse is located underground, and its outlet is on the right bank of Manaschhu. Since in order to construct the original outlet, thick overburden has to be excavated, the outlet was shifted to 1.7km upstream of Manaschhu.  Thick unconsolidated talus material covers the bedrock around the powerhouse site. Rocks distributed under the talus materials are Moderately Weathered (MW).  Rocks around the powerhouse cavern seem to be schist and phyllite of the Daling Formation (pCd).  If the Uzorong project is not realized, the powerhouse of Sherichhu could be a ground surface-type, and the water head would increase by 100m.

Natural Park /  According to the GIS data provided by the Department of Forest and Protected Area Park Services, the project area is outside the protected area network.

However, according to a Forest Ranger at Bumdeling Wildlife Sanctuary, the closest protected area to the project area, the intake area seems to be within or on the border of the sanctuary.

Prosperous fauna /  The intake area is covered mainly by Subtropical Broad-leaved Forest. flora The waterway area is covered mainly by Chir Pine Forest. The outlet area is in a Chir Pine Forest.  According to a Forest Ranger at the sanctuary, Red Panda (EN), Tiger (EN), Leopard (VU), and other endangered species are present in the Natural / Social Environment project area. Putitor (Golden) Mahseer (EN) may come to the project area because the species is present in the main river, Drangmechhu.

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Resettlement / According to the GIS data from NLC and interview with Drametse Gewog: Compensatory assets  No resettlement is required.  No private land acquisition is required.

Historical / Cultural  According to the GIS data from NLC and interview with Drametse Heritage Gewog, no cultural heritage sites are present at the project site.

Other  According to the GIS data from NLC, the waterway passes through private agricultural land.

Photo 1 Intake Weir Site Photo 2 Upstream of Weir

Photo 3 Surge Tank Site Photo 4 Powerhouse Site (Ground Surface Type)

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Figure A 1-65 Plot Plan (G-13)

Figure A 1-66 Longitudinal Profile (G-13)

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1.35 G-14R: Uzorong_Rev

Project Name G-14R: Uzorong_Rev Date 4/12/2018 Basin Manaschhu Tributary Manaschhu Dam (Weir) Latitude: 27° 13' 56.04" N Longitude: 91° 23' 29.64" E

Powerhouse Latitude: 27° 13' 8.88" N Longitude: 91° 23' 43.23" E Type Pondage RBL at Dam EL 530m Installed Dam/Weir 764 MW 168 (23) m Capacity Height

Primary Data Max. 614 m3/s Salient Crest Length 330 m General Discharge Features Features Effective Waterway 144.2 m 1,860 m Head Length Catchment Live Storage 10,175 km2 217.3 MCM Area Capacity Elongation from Existing Dam site: 1.5 km from the existing Main Road Road Powerhouse Site: 3km and 1 bridge from the dam site Access General Geology Geofacies (compiled by Long et al., 2011) are as follows: The subsurface geology of the project area falls in the Shumar Formation (pCs) of the Daling-Shumar Group in the Neoproterozoic Period. Light-gray to white, tan-weathering, very fine-grained, medium to thick- bedded, cliff-forming quartzite. Interbeds of thin to thick-bedded, green,

muscovite-biotite schist and phyllite with diagnostic sigmoidal quartz vein boudins become more common in the upper section. The Daling Formation (pCd), which is overlain by pCs, has similar lithologies to pCs, but is dominated by schist and phyllite. Quartzite is thin to medium-bedded, and medium-gray Limestone interbeds are rare. Lower contact is gradational with the Shumar Formation.

 There is a fault or unconformity inclining to the north at 15 degrees, Geography / Geology just downstream of the dam site. The upper layer’s strata is inclined to the north, and the lower’s, to the south. The surface of their boundary is covered by vegetation, and the stratigraphic boundary seems to be N45W/15NE. This may be a boundary between pCs and pCd (Photo 4).

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Dam / Intake  The morphology of the dam site is asymmetric. The left bank is almost vertical and the right bank inclination is 25 degrees, covered by sparse pine forest on a thin overburden. The riverbed is covered by cobble gravel and the river width is about 70m (Photos 1 and 2).  The rock of the steep cliff on the left abutment seems to be schist bearing quartzite boudins. This has a sigmoidal normal sense drag, and the layer’s strike and dip is N50E/40-50NW.  Weathering grade of the rock is MW. There are some deep grooves perpendicular to the strata, and some meltage clings to the bottom (Photo 3). Accordingly, since the bedrock may contain some calcareous material, it is not recommended for a gravity dam site of over 150m in height.  Accordingly, the dam site was shifted to about 1.5 km downstream from the original site, where the riverbed elevation is 10m lower than the original site.  In previous reconnaissance by DHPS, quartzite bedrock was outcropped. It is expected that the bedrock of the revised dam site area will belong to pCs and the bedrock seems to be better than the original site area (Photo 5). However, there are some unstable slopes observed on the Google Earth image.

Waterway  The rock classification along the upper 1/3 of the headrace tunnel seems to be Class-IV and the RMR value is estimated to be 37. That of the other part seems to be Class-III and the RMR value is estimated to be 47.

Powerhouse  There are no particular issues at the powerhouse or outlet sites. However, an unstable slope is observed just downstream of the outlet.

Natural Park / Protected  The project area is outside the protected area. Area Prosperous fauna / flora  The project area is covered by Chir Pine Forest.  According to a Forest Ranger at Bumdeling Wildlife Sanctuary, Leopard (VU) is common in the area, and, in Drangmechhu, Putitor Golden Mahseer (EN) is present. Footprints of Leopard were observed by the DHPS survey team during the last survey at the project area.  According to the villagers of Uzorong and Kanglung Gewog, Black- necked Crane (VU) has been observed during November at the confluence of Khengri and Gongri since 2016: one in 2016, two in

Natural / Social Environment 2017 and three in 2018.

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Resettlement / According to the GIS data and interview with Uzorong Gewog, Kanglung Compensatory assets Gewog, Drametsue Gewog and representatives of villages (Tshogpas) in the project site;

 GIS data shows that resettlement of a total of 35 hhs will be required in the reservoir area; however, as a result of site survey and information from the gewogs and Tshogpas, as of January 2019, only 4 settlements (4 shops cum houses) exist and other houses are for temporary construction workers, staff quarters for the Department of Roads or are abandoned.  Private land acquisition of approx. 116 acres in total for agriculture and other purposes will be required in the reservoir area.  Submerged facilities: Lemongrass Processing Unit belonging to the Farmers’ Cooperative, Sand and Surface Rock collection sites belonging to the NRDCL, two suspension bridges and two motorable bridges, Territorial Forest Office and its nursery, part of a highway, Department of Roads office and staff quarters, and a hydro metering station.

 No resettlement or impact on private land

Historical / Cultural  According to the GIS data from NLC, there are no cultural heritage Heritage sites. However, site reconnaissance and interviews with the Gewogs and village representatives revealed that “Aja Ney Ju” would be submerged at the junction of two rivers, Sherichhu and Gongri. There is a chorten and a stone throne for Buddhist Saint Guru Rinpoche, who visited Bhutan in the 8th century. Local people consider it a holy site.

Other  According to Uzorong gewog, positive impacts on local affairs may occur due to the project. Road improvement (widening and blacktopping) would divert traffic flowing through Trashigang via Samdrup Jongkhar, and Uzorong would be used as a bypass, reducing the distance travelled on the east-west highway.  While Kanglung Gewog officials communicated that there is no substitute land for replacement, an Uzorong Gewog official stated that land replacement would not be a problem.  According to Kanglung Gewog officials, in the submerged area of the project, a horticulture cultivation project for unemployed youth is planned in Membrang in Kanglung, supported by the current Queen. The project will start in 2019.  According to Drametse Gewog, along the stretch of the Drametse Gewog bordering the Gongri River, the Gewog has identified land for agricultural activity under the Land User Certification Program to boost agricultural production in the country.

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Photo 1 Dam Site Photo 2 Close-up of Left Bank of Dam Site

Photo 3 Close-up of Meltage on bottom of Groove Photo 4 Stratigraphic Boundary on Left Bank just downstream of Dam Site

Photo 5 Uzorong Rev Dam Site

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Figure A 1-67 Plot Plan (G-14_Rev)

pCs

Figure A 1-68 Longitudinal Profile (G-14_Rev2)

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1.36 G-16: Jerichhu

Project Name G-16 : Jerichhu Date 30/11/2018 Basin Manaschhu Tributary Jerichhu Dam (Weir) Latitude: 27° 8' 51.18" N Longitude: 91° 25 '43.08" E

Powerhouse Latitude: 27° 6' 46.43" N Longitude: 91° 22' 50.74" E

Data Type ROR RBL at Dam EL 1,020 m Installed Dam/Weir 39 MW 5 m Capacity Height

Primary Max. 9.2 m3/s Salient Crest Length 30 m General Discharge Features Features Effective Waterway 483.6 m 6,844 m Head Length Catchment Live Storage 153 km2 MCM Area Capacity Elongation from Existing Dam site and Powerhouse Site: No access road either to the intake or Road powerhouse site. 

There are two routes to access Banag Tang Village near the intake site. One is 42km from Wamrong and the other is 39km from Ngangshing Tshangkhang Ray. Accessing the village takes 2.5 hours Access by car via either route.  For construction of the project, more than 10km of new road should be constructed, and the 40km-long existing road should be improved.

General Geology Geofacies (compiled by Long et al., 2011) are as follows: The subsurface geology of the project area falls in the Manas Formation (Pzm) of the Baxa Group in the Lesser Himalayan Zone, in the Neoproterozoic to the Cambrian [?] Period. Gray to white, medium to thick-bedded, medium to coarse-grained, locally-conglomeratic quartzite exhibiting common trough cross- bedding, interbedded with dark-gray to dark-green, thin-bedded to

thinly-laminated phyllite, and medium-gray dolostone. Pangsari Formation (pCd), which belongs to the Baxa Group as well, covers this Formation with a thrust fault dipping to the SE on the same terrain.

Weir / Intake  The intake is located at the mid-stream of Jerichhu, the topography of which forms a V-shaped valley. There are no problems in Geography / Geology employing a 5m high intake in terms of topographical and geological conditions, since thin bedded but fresh quartzite and phyllite bedrock was observed on the tributary.  Some eluted materials are observed on the forest road slopes near Banag Tang Village, which is located in the eastern part of the project site. This might have been caused by solution from some calcareous rocks in the Pangsari formation (pCd).

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Waterway  The waterway is planned to be located on the left bank of the river, where the geological conditions seem to be better than those in the above mentioned area, which belongs to the Manas formation (Pzm) in the upper horizon.  Thin bedded but fresh quartzite and phyllite bedrock is expected along the headrace tunnel. The rock classification along the headrace tunnel is estimated to be Class-III and the RMR value is estimated to be 38.  An oblique lineament is observed in the Google Earth image.

Powerhouse  The underground bedrock around the powerhouse seems to be preferable, since the geology consists of stratified quartzite and, partially, phyllite.  The above strata seem to be flaggy. The longitudinal axis of the powerhouse cavern should be set perpendicular to the strike of the strata because the dip seems to be around 30 degrees.

Natural Park / Protected  The project area is outside the protected area. Area Prosperous fauna / flora  The project area is covered by Subtropical Broad-leaved Forest (the

JICA Survey Team visited only the intake area).  According to the villagers of Phogchiri, a settlement close to the intake, Leopard (VU) is present in the area.

Resettlement / According to the GIS data from NLC and interview with the Shumer Gewog: Compensatory assets  No resettlement is required.  No acquisition of private land is required.

Historical / Cultural  According to the GIS data from NLC and interview with the Shumer Heritage Gewog, no directly affected cultural heritage sites are found at the project site. Natural / Social Environment

Other  The waterway passes some private land owned by around 10 hh or so.

Photo 1 Intake Weir Site Photo 2 Waterway Route

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Figure A 1-69 Plot Plan (G-16)

Figure A 1-70 Longitudinal Profile (G-16)

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1.37 G-19: Nagor

27/11/2018 Project Name G-19: Nagor Date 30/11/2018 Basin Manaschhu Tributary Gangchatpu Latitude: 27° 5' 13.80" N Longitude: 91° 6' 16.48" E Dam (Weir) 27° 4' 44.96" N 91° 6' 6.12" E Powerhouse Latitude: 27° 1' 46.73" N Longitude: 91° 12' 50.94" E

Type ROR RBL at Dam EL 925 m Installed Dam/Weir 59 MW 5 m Capacity Height Primary Data Max. 10.9 m3/s Salient Crest Length 30 m General Discharge Features Features Effective Waterway 1,003 m 627.8 m Head Length 13,644m Catchment Live Storage 146 km2 MCM Area Capacity Elongation from Existing Dam site: Accessible via local forest road Road (improvement of the existing road, which is 38km from the bridge crossing Manaschhu to Nagor Village and 7km from Nagor Village to the intake site, is required)

Access Powerhouse Site: a bridge crossing Manaschhu and 0.5km of new access road is required.

General Geology Geofacies (compiled by Long et al., 2011) are as follows: The subsurface geology of the project area falls in the Manas Formation (Pzm) of the Baxa Group in the Lesser Himalayan Zone, in the Neoproterozoic to the Cambrian [?] Period. Gray to white, medium to thick-bedded, medium to coarse-grained, locally-conglomeratic quartzite exhibiting common trough cross- bedding, interbedded with dark-gray to dark-green, thin-bedded to thinly-laminated phyllite, and medium-gray dolostone (Bhargava, 1995; Tangri, 1995a; Long et al., 2011A). Locally divided dolostone is taken into there. Furthermore, the Pangsari Formation (pCd), which belongs to the Baxa Group as well, overlies this

Formation with a thrust fault.

Weir / Intake  There may be no particular issues around the weir or intake site, because the bedrock around the area consists of quartzite accompanied partially with phyllite.  However, the total water flow rate at both intake sites seems to be 1.0 - 1.5 m3/s, which is a noticeably lower flow than the designed

Geography / Geology discharge.

Waterway  Collapsed slopes caused by hydrothermal alteration are distributed along the forest road near Nagor village. Since their permeability seems to be very low and groundwater may be stored there, special attention should be paid during excavation of the headrace tunnel.  2/3 of the HRT route seems to belong mainly to the Manas Formation (Pzm), and the other 1/3 seems to belong to the Pangsari Formation (pCd), for which the rock classification is estimated to be Class-III and RMR value, 39.  The headrace tunnel will encounter a thrust fault having an anti-form.

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Powerhouse  The topography above the powerhouse site is quite steep at 60 degrees. However, such a steep slope may generally yield some semi- vertical cracks caused by mass rock creeping, as shown at the Kuri Gongri dam site. Accordingly, it is recommended to pay special attention to safety during construction.  Since the bedrock around the powerhouse and outlet site consists of dolostone and the rock seems sound, careful geological investigation, especially in terms of permeability and the distribution of underground caves, should be carried out.

Natural Park / Protected  The project area is outside the protected area. Area Prosperous fauna / flora  The project area is covered mainly by Subtropical Broad-leaved Forest. The area of the waterway is covered by Subtropical/Warm Broad-leaved Forest.

 According to the villagers of Nagor, a village close to the intakes, Leopard (VU) and Asian Black Bear (VU) are present in the project area. Putitor Golden Mahseer (EN) is present in Manaschhu, where the outlet is located.

Resettlement / According to the GIS data from NLC: Compensatory assets  No resettlement is required.  Acquisition of private land may be required in the powerhouse location.

Natural / Social Environment Historical / Cultural  According to the GIS data from NLC, there are no directly affected Heritage cultural heritage sites at the project site.

Other

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Photo 1 Leached Rock due to Hydrothermal Photo 2 Weathered Quartzite and Phyllite Alteration near Nagor Village distributed near No.1 Weir Site

Photo 3 Weir Site (Intake1) Photo 4 Upstream side of Weir (Intake2)

Photo 5 Penstock and Powerhouse Site

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Figure A 1-71 Plot Plan (G-19)

Figure A 1-72 Longitudinal Profile (G-19)

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1.38 G-22: Panbang

26/11/2018 Project Name G-22: Panbang Date 27/11/2018 Basin Drangmechhu Tributary Manaschhu Dam (Weir) Latitude: 26° 51' 41.29" N Longitude: 91° 0' 18.92" E

Powerhouse Latitude: 26° 51' 32.19" N Longitude: 91° 0' 14.74" E Type Pondage RBL at Dam EL 121 m

Installed Dam/Weir 1,100 MW 155 (21) m Capacity Height Primary Data Max. 1,006.4 m3/s Salient Crest Length 406 m General Discharge Features Features Effective Waterway 119.3 m 600 m Head Length Catchment Live Storage 20,944 km2 495.2 MCM Area Capacity Elongation from Existing Dam site: accessible via Panbang town Road (improvement of 3km of existing road from Panbang town is required)

Access Powerhouse Site: As above

General Geology Geofacies (compiled by Long et al., 2011) are as follows: The subsurface geology of the project area falls in the Manas Formation (Pzm) of the Baxa Group in the Lesser Himalayan Zone, in the Neoproterozoic to the Cambrian [?] Period. Gray to white, medium to thick-bedded, medium to coarse-grained, locally-conglomeratic quartzite exhibiting common trough cross- bedding, interbedded with dark-gray to dark-green, thin-bedded to thinly-laminated phyllite, and medium-gray dolostone (Bhargava, 1995; Tangri, 1995a; Long et al., 2011A). E-W trend Syncline, anticline axis, MBT (Main Boundary Thrust) and

some hydrothermal alteration zones pass through the project site almost parallel to the Manas river.

 Quartzite with thin phyllite (less than 1m) is distributed along the local road on the right bank of the dam site. Three directions of joint set are observed on the MW condition outcrop (Photo 3), and since the rock is flaggy from place to place, it is easily broken by a hammer. 3 Geography / Geology The rock hardness grade is estimated to be R3 (Medium strong rock).  SW (Slightly Weathered) rock is exposed on the left riverbank. The rock seems hard, however, and two or three directions of joint sets were observed as well (Photo 4).  A fracture zone is observed on the roadside downstream of the dam site, with an R2 (Weak rock) grade, for which the trend is almost parallel, or slightly oblique, to Manaschhu.  For such above-mentioned geological circumstances, construction of a concrete gravity high dam is very difficult.

3 Cannot be scraped or peeled with a pocket knife. Hand-held specimens can be fractured with a single firm blow of a geological hammer (after ISRM 1981).

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Dam / Intake  Since fractured Quartzite and/or Phyllite are distributed on the right bank of the dam site, the bedrock is expected to be insufficient as a foundation for an over-100m high dam.  In addition, two large scale slope failures observed at the right bank of the reservoir may cause a huge volume of sediment to enter the reservoir.  An alternative site, which is located 6km upstream of the original dam site, has been identified. Although the water head is reduced by 30m, its economic efficiency is much higher than that of the original plan. In addition, it has advantages in that the submergence of 15 households and sediment inflow from the above mentioned slope failures can be avoided.  Furthermore, its reservoir may be used as a lower pond for a PSPP scheme.  In a PSPP project, the tailrace may encounter a 20 to 30 m wide hydrothermal alteration zone.

Waterway  The intake and penstock are designed to be on the left bank.

Powerhouse  The original powerhouse site is located underground on the left bank.  It is recommended that the powerhouse be changed from an underground type to a ground surface type on the alluvial plain downstream to reduce construction costs.

Natural Park / Protected  The left side of the river belongs to a Multiple-use Zone (proposed) Area of Royal Manas National Park (about 15 km from the dam site to the upstream). Prosperous fauna / flora  The project area is covered by Subtropical Broad-leaved Forest.  According to a Forest Ranger of Panbang Range, Asian Elephant (EN) and Gaur (VU) come to the area in summer, and Putitor (Golden) Mahseer (EN) is present in the area. According to a villager from Yumdang, a village near the dam site, Leopard (VU) and Asian Black Bear (VU) are present in the area.  The dam will change the current seasonal water flow, which will create an impact on the downstream ecosystem (including Royal

Natural / Social Environment Manas National Park).

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Resettlement / According to the GIS data from NLC, and interviews with Ngakhor, Compensatory assets Norbugang, Bjoka, Dechengling and Dungming Gewogs and village representatives (Tshopas):  Resettlement of at least 45 settlements from 4 villages (Yumdang, Zarkapla Bali, Pato, and Gem de Ri) in 3 Chiwogs (Yumdang, Yangbari and Chapdonpa) will be required due to the reservoir. According to Gewog officials, resettlement of approx. 96 hh will be needed (Gewog-wise: Ngakhor: 12hh, Bjoka: 9hh, Dechengling: 25hh, Dungming: 3hh, Gondue: about 47hh).  According to the GIS data from NLC, approx. 700 acres of private land acquisition will be required due to the reservoir. According to Gewog officials, the use of private land is for residences, agriculture, livestock sheds, shops, sand quarries, some fallow land etc. (Gewog- wise: Ngakhor 35± acres, Norbugang: 45± acres, Bjoka: 130± acres, Dechengling: 175± acres; Dungming also has some private land).  According to the Google Earth map and the Gewog offices, many public facilities will be submerged or affected by the reservoir, such as farm roads, some parts of the Gyelposhing-Nganglam highway, 2 locations of sand and boulder collection sites for the NRDCL, a suspension bridge (for foot traffic) connecting Telung to Yangbari, a motorable Bailey Bride at Kurung River, and a motorable bridge at Sokporongchu.  No resettlement or private land acquisition.

Historical / Cultural  According to the GIS data from NLC, 1 chorten and 1 prayerwheel Heritage will be submerged in Ngangla Gewog. The community of Lhakhang is located very close to the water level.

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Other  Among affected villages, some have relatively high levels of poverty. According to Dungkhag and Bjoka Gewog officials, the community is comparatively poorer than other areas in the gewog. In Dumgmin Gewog, the village of Laniree, where the land is to be submerged, is under Mikuri Chiwog and is one of the chiwogs with a high incidence of poverty. It has also benefitted under the Tarayana-supported Livelihood Project. In addition, according to Dzongkhag and Gewog officials nearby and site observations, Yangbari Chiwog is relatively vulnerable economically and has support from HRH Prince Namgyal Wanchuk (4th King's uncle) to develop aquaculture production. The Tarayana foundation also has plans to support the construction of houses in this village.  Positive impacts are expected in terms of improved access to socio- economic benefits and local product sales will increase in some villages around the project site. For example, in Bjoka Gewog, the villages in Chapdemba Chiwog currently do not have road access and travel roughly 3-4 hours to reach Panbang from Zarkapla. The communities in Bjoka village are known for their cane and bamboo handicrafts, which could see an increase in sales with improvements in road connectivity and a reduction in transport costs.  Eco-tourism is on the rise with local tourists as well as foreign tourists. Indian visitors from across the border also frequent the Bhutanese side of the Manas National Park.  According to Gewog officials, the junctions of the Kerung and Kurung rivers are fishing grounds for HRH Prince Jigyel Ugyen Wangchuck (5th King's younger brother) for Golden Mahseer.  Gewog officials also stated that there are many opportunities for surface collection of sand and boulders along the stretch of the river from Kuri-Gongri to the Panbang area.

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Photo 1 Dam and Powerhouse Site Photo 2 Slightly sheared Quartzite Outcrop along Road downstream of Dam Site

Photo 3 Quartzite Outcrop on the right bank of Dam Photo 4 Quartzite Outcrop on the left Riverbed

Photo 5 Huge Collapse which may have beeen Photo 6 Hydrothermal Alteration Outcrop on the loosened by Hydrothermal Alteration 4.5km upstream left bank of Manaschhu 17km from Dam Site (No.115 of Dam Site flag in the Google Earth image below)

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Figure A 1-73 Plot Plan (G-19)

Figure A 1-74 Longitudinal Profile (G-19)

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1.39 N-1: Nyera Amari Kangpara (G)

Project Name N-1: Nyera Amari Kangpara (G) Date 02/12/2018 Basin Nyera Amari Tributary Shangri Dam (Weir) Latitude: 27° 15' 48.76" N Longitude: 91° 43' 33.82" E

Powerhouse Latitude: 27° 14' 35.02" N Longitude: 91° 44' 8.83" E Type ROR RBL at Dam EL 2,790 m Installed Dam/Weir 71 MW 5 m Capacity Height

Primary Data Max. 10.8 m3/s Salient Crest Length 30 m General Discharge Features Features Effective Waterway 762.6 m 6,261 m Head Length Catchment Live Storage 145 km2 MCM Area Capacity

Elongation from Existing Intake weir site: 16 km from Kangpara District Center Road Powerhouse site: 14 km from Kangpara District Center

Access (Total of 30km of new road should be constructed.)

General Geology Geofacies (compiled by Long et al., 2011) are as follows: The subsurface geology of the project area falls in the Structurally-lower Greater Himalayan section in the Greater Himalayan Zone of the Neoproterozoic-Ordovician [?] period. The uppermost section of the waterway route belongs to the Upper metasedimentary unit (GHlmu), with variable metamorphic grades: dominantly amphibolite facies (Gansser, 1983), partial melt- and often kyanite-, sillimanite-, or staurolite-bearing paragneiss, schist, and quartzite in the east (Grujic et al., 2002) and near the base in west-central Bhutan, and melt-free, dominantly upper greenschist-facies (Gansser, 1983) quartzite and biotite-muscovite-garnet schist in central Bhutan (Long and McQuarrie, 2010).

The next section of the waterway route belongs to the Orthogneiss unit (GHlo) from the Cambrian to the Ordovician Period. Cliff-forming, massive-weathering, granite-composition orthogneiss; generally, exhibits leucosomes and abundant feldspar augen. Paragneiss, schist, and quartzite intervals locally split out. Interpreted as deformed Cambrian-Ordovician granite plutons that intruded Greater Himalayan sedimentary protoliths thickens toward eastern Bhutan. The longest, which is up to more than half the length of the waterway Geography / Geology route, belongs to the Lower metasedimentary unit (GHlml). This features dominantly amphibolite-facies metasedimentary rocks, including quartzite, and biotite-muscovite-garnet schist and paragneiss often exhibiting kyanite, sillimanite, or staurolite, and partial melt textures. Orthogneiss intervals locally split out.

Weir / Intake  Though the team couldn’t reach the site, there seem to be no particular issues regarding weir construction.  The geology along the waterway route belongs to the Structurally- Waterway lower Greater Himalayan section, and the rock classification seems to Powerhouse belong to Class-II, with the RMR value estimated to be 65. Therefore, rocks along the headrace tunnel seem to be preferable for tunnel construction.

Natural Park / Protected  The project area is outside the protected area. / l t al m en on So tur En vir Na Area cia

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Prosperous fauna / flora  The project area is assumed to be covered by Cool Broad-leaved Forest.  According to Forest Rangers in Kangpara Gewog, Leopard (VU), Asian Black Bear (VU) and Sambar (VU) are present in the area. There is a fish called “Kheng Nga” in the local language, and this might be Putitor Golden Mahseer (EN).

Resettlement / According to the GIS data from NLC and interview with Kangpara Gewog: Compensatory assets  No resettlement is required.  No private land acquisition is required.

Historical / Cultural  According to the GIS data from NLC and interview with Kangpara Heritage Gewog, there are no historical/cultural heritage sites at the project site.

Other  According to Dzongkhag and Gewog officials, Nyera Amari is rich in local fish. Though the communities in the Kangpara Gewog do not have user rights/licenses for fishing, people occasionally eat fish as a protein source. They do not directly depend on fishing as a source of cash income.

 According to the Chief Forestry Officer (CFO) of the Territorial Forest Division, Trashigang, there may be a community fishing group with fishing user rights along the Nyera Amari. Also, a Forest Management Unit (FMU) of approx. several thousand acres has been proposed under the 12th FYP in Kangpara Gewog. If the FMU is designated, development activities will be restricted in this area.

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Figure A 1-75 Plot Plan (N-1)

Figure A 1-76 Longitudinal Profile (N-1)

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1.40 N-2: Lamai Gonpa

2/12/2018 Project Name N-2: Lamai Gonpa Date 3/12/2018 Basin Nyera Amari Tributary Shangri Dam (Weir) Latitude: 27° 12' 29.92" N Longitude: 91° 43' 42.41" E

Powerhouse Latitude: 27° 8' 39.65" N Longitude: 91° 43' 35.01" E Type ROR RBL at Dam EL 1,935m

Installed Dam/Weir 37 MW 5 m Capacity Height Primary Data Max. 14.1 m3/s Salient Crest Length 30 m General Discharge Features Features Effective Waterway 302.3 m 9,695 m Head Length Catchment Live Storage 188 km2 MCM Area Capacity Elongation from Dam site: About 20km of new road construction is required. Existing Road Powerhouse Site: Accessible using the existing road Access General Geology Geofacies (compiled by Long et al., 2011) are as follows: The subsurface geology of the project area includes the Shumar Formation (pCs), Daling Formation (pCd) of the Daling-Shumar Group of the Neoproterozoic Period and Jaishidanda Formation (Pzj) of the Neoproterozoic-Ordovician [?] period in sequence from south to north. The Shumar Formation (pCs), which is distributed only in the area surrounding the powerhouse site, consists of light-gray to white, tan- weathering, very fine-grained, and medium to thick-bedded, cliff- forming quartzite. Interbeds of thin to thick-bedded, green, muscovite- biotite schist and phyllite with diagnostic sigmoidal quartz vein boudins become more common in the upper section. The Daling Formation (pCd), which covers a high proportion of the waterway route, has similar lithologies to the Shumar Formation but is

dominated by schist and phyllite. Quartzite is thin to medium-bedded, and medium-gray limestone interbeds rarely exist. Lower contact is gradational with the Shumar Formation. The Jaishidanda Formation (Pzj), which is distributed in the uppermost area, near the intake site, consists of gray, biotite-rich, locally garnet- bearing schist, interbedded with gray to tan, biotite lamination-bearing, lithic clast-rich quartzite. Its facies change from greenschist in the upper part to amphibolite in the lower part. Geography / Geology Weir / Intake  The intake weir site is planned to be on the Shangri, which is a tributary of Nyera Amari.  Earthquake intensity in the project area is high and MCT passes near the intake site.

Waterway  The waterway route is selected to be on the left bank of the Shangri.  Since schist and phyllite seem to be dominant along the waterway route, the alignment of the headrace tunnel should be carefully examined to avoid weak zones and anisotropic rocks.  The headrace tunnel seems to run in pCd, for which the rock classification is estimated to be Class-III and the RMR value is estimated to be 42.

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Powerhouse  Since the powerhouse site is located near a monastery, the accurate distance should be examined.  No particular issues are anticipated in constructing the underground powerhouse, since the powerhouse site seems to be located in the thick Quartzite layer. However, in order to avoid encountering the hydrothermal alteration zone and ST (Shumar Thrust) during the excavation of the underground cavern, detailed geological conditions (especially the distribution of anisotropic rocks such as phyllite and schist) should be carefully investigated.

Natural Park / Protected  The project area is outside the protected area. Area  According to the Terrestrial Forest Division, Trashigang, the establishment of a forest management unit has been proposed around the project area and this is in the process of being finalized. The size of the unit is about 5,000 ha but the details of its location have not been decided.

Prosperous fauna / flora  The inlet and waterway areas are assumed to be covered by Warm Broad-leaved Forest. The outlet area is covered by Warm Broad-leaved Forest.  According to Forest Rangers in Kangpara Gewog, Leopard (VU), Asian Black Bear (VU) and Sambar (VU) are present in the area. There is a fish called “Kheng Nga” in the local language, and this might be Putitor (Golden) Mahseer (EN).

Resettlement / According to the GIS data from NLC and interview with Kangpara Gewog:

Compensatory assets  No resettlement is required.  No private land acquisition is required.

Historical / Cultural  According to the GIS data from NLC and interview with Kangpara Heritage Gewog, approx. 0.33 km from the powerhouse and the waterway is the oldest cultural heritage site, known as Lamai Gonpa Lhakhang. It is one of the most important cultural heritage sites in the Kangpara Gewog. Both the Dzongkhag and Gewog Office have concerns that, due to the blasting and tunneling work, the Lhakhang (temple) might get damaged.

Natural / Social Environment Other  The waterway runs through some private land and a community forest. According to Dzongkhag and Gewog officials, Nyera Amari is rich in local fish. Though the communities in the Kangpara Gewog do not have user rights/licenses for fishing, people occasionally eat fish as a protein source. They do not directly depend on fishing as a source of cash income.

 According to the Chief Forestry Officer (CFO) of the Territorial Forest Division, Trashigang, there may be a community fishing group with fishing user rights along the Nyera Amari. Also, a Forest Management Unit (FMU) of approx. several thousand acres has been proposed under the 12th FYP in Kangpara Gewog. If the FMU is designated, development activities will be restricted in this area.

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Photo 1 Powerhouse Site Photo 2 Quartzite dominant Geology distributed around Powerhouse Site

Photo 3 Weathered Quartzite and Phyllite at the Photo 4 Nyera Amari Condition waypoint 150

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Figure A 1-77 Plot Plan (N-2)

Figure A 1-78 Longitudinal Profile (N-2)

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1.41 N-3: Peydung-Kangpar_Rev

2/12/2018 Project Name N-3: Peydung-Kangpar_Rev Date 3/12/2018 Basin Nyera Amari Tributary Nyera Amari Dam (Weir) Latitude: 27° 7' 40.10" N Longitude: 91° 42'12.60" E

Powerhouse Latitude: 27° 5' 52.46" N Longitude: 91° 36'51.67" E Type ROR＋Pond RBL at Dam EL 1,575m

Installed Dam/Weir 102 MW 58 (28) m Capacity Height Primary Data Max. 28.4 m3/s Salient Crest Length 120 m General Discharge Features Features Effective Waterway 418.5 m 12,500 m Head Length Catchment Live Storage 379 km2 0.7 MCM Area Capacity Elongation from Existing Dam site: Accessible using the existing black-top road. Road Powerhouse Site: Accessible using the existing black-top road. Access General Geology Geofacies (compiled by Long et al., 2011) are as follows: The subsurface geology of the project area falls in Shumar Formation (pCs) of Daling-Shumar Group in Neoproterozoic Period. Light-gray to white, tan-weathering, very fine-grained, medium to thick-bedded, cliff-forming quartzite. Interbeds of thin to thick- bedded, green, muscovite-biotite schist and phyllite with diagnostic sigmoidal quartz vein boudins become more common in the upper section.

 A landslide is observed on the slope above the planned powerhouse site, which seems to have been caused by hydrothermal alteration. The alteration is observed along the phyllite layer and its direction seems to be almost parallel to the

headrace tunnel. Therefore, the weak zone caused by hydrothermal alteration should be carefully examined to decide the tunnel alignment and the powerhouse site location (Photo 3).

Dam / Intake  The original dam was designed as a concrete gravity type dam, 58m high. However, a weir of less than 15m in height is recommended so that a ground surface type desilting basin can

Geography / Geology be constructed on the alluvium plain just downstream of the dam site.  The river flow rate of Shangri was 4 - 5m3/s and that of Gongri was 2 - 3 m3/s. The total river flow rate at the dam site is estimated to be 6 - 7m3/s via visual observation. The river flow rate at the powerhouse site seems to be less than 5m3/s. Some tributaries and streams surrounding the project area have water flows that are less than expected, and others are more than expected.  As for topography of the dam/intake site, the right bank’s slope is steep at 55 degrees, while the left bank’s slope is gentle at 35 degrees.  No outcrops of bedrock are found, and boulder gravel covers the riverbed surrounding the dam site. Since thick sediment deposit is anticipated, a floating type weir is recommended.

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Waterway  Quartzite is dominant along the waterway route. The average thickness of quartzite is 0.4m, and an interbedded thin phyllite band with a thickness of 10mm was observed. Strike and dip of the bedding plane is N70-80E/40NW. Two sets of joint systems with a 0.2m interval are observed on the cut slope of the road (Photo 2).  Weathered bedrock of schist or phyllite is expected to be distributed at several parts of the waterway route near the intake.  The headrace tunnel may run in pCs, for which the rock classification is estimated to be Class-II and RMR value is estimated to be 63.

Powerhouse  Per the site reconnaissance, the surge tank, powerhouse and outlet were shifted downstream to just upstream of the intake of Nyera Amari I so that an additional water head of 70m could be gained (refer to the below Plot Plan).  There seem to be no particular issues regarding the underground powerhouse site. However, the hydrothermal alteration zone and ST (Shumar Thrust Fault) should be avoided.

Natural Park / Protected  The project area is outside the protected area. Area Prosperous fauna / flora  The inlet area is covered by Warm Broad-leaved Forest. The waterway and outlet areas are covered by Chir Pine Forest.  According to Forest Rangers in Kangpara Gewog, Leopard (VU), Asian Black Bear (VU) and Sambar (VU) are present in the area. There is a fish called “Kheng Nga” in the local language, and this might be Putitor Golden Mahseer (EN).

Resettlement / According to the GIS data from NLC and interview with Kangpara Compensatory assets Gewog,  No resettlement is required.  Acquisition of private land (wetland & dry land; currently it is left fallow) of approx. 2 acres will be required in the reservoir area.

Historical / Cultural  According to the GIS data from NLC, no cultural heritage sites are

Environment Heritage present at the project site.

Other  The waterway might pass through a community forest.

Natural / Social  According to Dzongkhag and Gewog officials, Nyera Amari is rich in local fish. Though the communities in the Kangpara Gewog do not have user rights/licenses for fishing, people occasionally eat fish as a protein source. They do not directly depend on fishing as a source of cash income.

 According to the Chief Forestry Officer (CFO) of the Territorial Forest Division, Trashigang, there may be a community fishing group with fishing user rights along the Nyera Amari. Also, a Forest Management Unit (FMU) of approx. several thousand acres has been proposed under the 12th FYP in Kangpara Gewog.

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Photo 1 Intake Weir Site (and desilting chamber) Photo 2 Quartzite distributed along Road above Powerhouse

Photo 3 Weakened Layer caused by Photo 4 Downstream View from Powerhouse Hydrothermal Alteration

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Figure A 1-79 Plot Plan (N-3)

Figure A 1-80 Longitudinal Profile (N-3)

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Figure A 1-81 Geological Cross Section (N-3_Rev)

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1.42 N-3R: Paydung-Kangpar_Rev2

Project Name N-3R: Paydung-Kangpar_Rev2 Date 26/01/2019 Basin Nyera Amari Tributary Nyera Amari Dam (Weir) Latitude: 27° 9' 3.17" N Longitude: 91° 42' 9.73" E

Powerhouse Latitude: 27° 5' 47.50" N Longitude: 91° 36' 16.48" E Type ROR RBL at Dam EL 1,675m

Installed Dam/Weir 73 MW 5 m Capacity Height Primary Data Max. 17.3 m3/s Salient Crest Length 40 m General Discharge Features Features Effective Waterway 488.3 m 12,750 m Head Length Catchment Live Storage 231 km2 MCM Area Capacity

Elongation from Existing Dam site: Accessible using the existing black-top road. Road Powerhouse Site: Accessible using the existing black-top road.

Access

3

River Flow Rate 2.5 - 3 m /s (Eye Measurement)

Hydrology Sediment 0.5 – 1m (Gravel ~ Boulder) General Geology Geofacies (compiled by Long et al., 2011) are as follows: The subsurface geology of the project area falls in the Shumar Formation (pCs) of the Daling-Shumar Group in the Neoproterozoic Period. Light-gray to white, tan-weathering, very fine-grained, medium to thick-bedded, cliff-forming quartzite. Interbeds of thin to thick- bedded, green, muscovite-biotite schist and phyllite with diagnostic sigmoidal quartz vein boudins become more common in the upper

section.

 A landslide is observed on the upper slope of the planned powerhouse site, which might have been caused by hydrothermal alteration being exposed on the road side. The alteration occurs along the phyllite layer, and its direction may be almost parallel to the HRT. Hence, the tunnel alignment and the powerhouse site must be carefully examined to avoid the Geography / Geology weak zone caused by hydrothermal alteration (refer to the figure shown below).

Dam / Intake  Since the Laimai Gonpa project was hard to develop due to low economic efficiency, the intake site was shifted to the upper stream of the Nyera Amari river.  No outcrops of bedrock are found, and gravel covers the riverbed surrounding the weir site. Since thick sediment deposit is anticipated, a trench weir type would be suitable (Photo 1).

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Waterway  The waterway is located on the right bank along the river.  Quartzite is dominant along the waterway route. The average thickness of quartzite is 0.4m, and an interbedded thin phyllite band with a thickness of 10mm is observed. Strike and dip of the bedding plane is N70-80E/40NW. Two sets of joints with a 0.2m interval are observed on the cut slope of the road (Photo 2).  At some parts of the waterway route near the intake, weathered bedrock of schist or phyllite is expected. Therefore, it is recommended to carry out geological investigations to examine the existence of weak zones.  The HRT may pass through pCs, which is assumed to be Class- II rock with an estimated RMR value of 63 (engineer’s intuition).

Powerhouse  It is recommended to shift the surge tank, powerhouse and outlet downstream to just upstream of the intake of Nyera Amari I so that an additional 70m of head can be acquired (Photo 3).  Particular issues may not occur at the underground powerhouse site. However, the hydrothermal alteration zone and ST (Shumar Thrust) should be avoided (Photo 4).

Natural Park / Protected  The project area is outside the protected area. Area Prosperous fauna / flora  The inlet area is covered by Warm Broad-leaved Forest. The waterway and outlet areas are covered by Chir Pine Forest.  According to Forest Rangers in Kangpara Gewog, Leopard (VU), Asian Black Bear (VU) and Sambar (VU) are present in the area. There is a fish called “Kheng Nga” in the local language, and this might be Putitor Golden Mahseer (EN).

Resettlement / According to the GIS data from NLC: Compensatory assets  No resettlement is required.  No private land acquisition is required.

Historical / Cultural  According to the GIS data from NLC and interview with Heritage Kangpara Gewog, no cultural heritage sites are present at the project site.

Natural / Social Environment Other  According to Dzongkhag and Gewog officials, Nyera Amari is rich in local fish. Though the communities in the Kangpara Gewog do not have user rights/licenses for fishing, people occasionally eat fish as a protein source. They do not directly depend on fishing as a source of cash income.

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Photo 1 Revised Weir Site

Photo 2 Quartzite distributed along Road above Photo 3 Downstream View from Powerhouse Powerhouse

Photo 4 Weakened Layer caused by Hydrothermal Alteration

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Figure A 1-82 Plot Plan (N-3 Rev2)

pCs

Figure A 1-83 Longitudinal Profile (N-3)

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Figure A 1-84 Geological Cross Section (N-3_Rev2)

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