II. Environment Clearance

The Environment Clearance is pre-requisite for any construction and developmental activities to ensure minimum impacts on the environment. Thus, the Environmental Clearance for construction and operation of 1020MW PHPA-II from the Department of Environment & Climate Change (DECC) was renewed and obtained on March 14, 2024 with validity till March 13, 2028. The PHPA-II, besides the main package Environmental Clearance have also obtained and issued clearances from different stakeholders/agencies as follows:

Table A: Total Clearance obtained (Till March, 2024):

III. Environment Management and Mitigation measures

Water Environment 

a) Sanitation facilities

• The workers camps were constructed with proper toilets with proper septic tanks and drainage system to ensure that the discharge from each toilet is collected in the tank and no discharge is drained into the surrounding water bodies.
• The waste generated at each worker camp and work site is collected on daily basis and disposed at landfill site.

b) Sedimentation tank and drainage system

• The sedimentation tanks were constructed at crusher plants/batching plant, auto workshops and at each tunnel to ensure that the wastewater is treated prior to discharge.
• To avoid increasing of sediments from the muck disposal site, a proper drainage system has been constructed in order to avoid blockage and formation of pool.

c) Sewage treatment plant

• The sewage treatment plant was constructed for the project colony at Pheytheykha to treat effluents prior to the discharge.

d) Water quality monitoring

• The water quality monitoring is carried out every month in order to ensure that the quality of water is within the standard set by DECC. The result of the water quality monitoring is submitted to DECC every month.
• The following parameters are considered during the water quality monitoring:
• TDS and TSS, BOD, Conductivity, Dissolved Oxygen, pH & Temperature

AIR ENVIRONMENT 

• In order to control the dust emission at project site, two water tankers were deployed for sprinkling water along the highway/road and at project sites.
• Each Contractor deploys water tanker along the project roads and at their respective work site including muck disposal site to suppress dust due to movement of heavy trucks.
• All the project vehicles were subjected to emission test and frequent inspection is being carried out by

project officials and RSTA officials to ensure that the emission from all the vehicles deployed for the project purpose are within the set standard.

• The dust emission from the crusher plant is being controlled through installation of water sprinkling system wherever required with regular monitoring and control blasting method is being adopted to ensure minimum dust generation.
• The use of firewood at the workers camp is restricted to prevent and avoid the risk of fire and emission of CO/CO₂ into atmosphere.
• In order to minimize the dust emission along the primary national highway due to continuous movement of vehicle, the re-carpeting (black-top) of highway was carried out by the Project from Dam site till Tail Race Tunnel.

Land Environment

Compensatory Afforestation

As per the Detail Project Report, about 300 ha of forest area will be affected or lost during the construction of 1020MW PHPA-II and it is stated that the compensatory afforestation of twice the area affected or lost should be executed by PHPA-II.

Accordingly, the project has executed the Compensatory Afforestation of 600 ha (300ha X 2) in five neighboring districts of Gasa, Punakha, Wangdue, Dagana and Tsirang through Department of Forest & Park Services (DoFPs) upon signing of Memorandum of Understanding (MoU) with Gross National Happiness Commission (GNHC). The Compensatory Afforestation details is tabulated below:

Muck disposal sites and rehabilitation

There are ten muck disposal sites measuring about 151.036 acres identified for PHPA-II to dump muck and boulders excavated from various tunnelling works (The detail is given in the following table). After, the completion of mucking activity, the dump yards should be properly developed with slope stabilization and revegetate to the extent possible with various tree and grass species as per the requirement of Detailed Project Report, Land Lease Agreement and other Environmental obligations.

Accordingly, PHPA-II has completed rehabilitation for 38.5 acres of exhausted muck disposal sites and handed over to the Dzongkhag Administration of Wangdue.  All the completed rehabilitation sites have more than 99% survival rate and are well established for natural succession. Further, these rehabilitation sites can be used as gene pool to collect seeds of various tree & grass species in the future and some of the rehabilitation sites can also be developed into green eco parks by the local communities.   

Conservation of White Bellied Heron (Ardea insignis)

In the year 2011, the PHPA-II in coordination with Royal Society of Protection of Nature (RSPN) has initiated a pilot artificial incubation of WBH eggs at Bhumitsawa along the Pochu bank in Punakha. Out of the two eggs that has been collected and incubated, one hatched on 7^th May, 2011. The fully grown chick was released on 77^th day i.e on 17^th September, 2011.

Further, the PHPA-II has signed a MoU with RSPN on 17^th November, 2016 for construction of WBH conservation facility at Chanchey under Tsirang Dzongkhag. The following facilities were constructed and handed over to RSPN on 27^th November, 2020 for operation & maintenance:

1. Construction of staff quarter, laboratory and Office
2. Fish pond and Aviaries
3. Access road
4. WBH public information & exhibition center
5. Public toilet

Golden Mahseer (Tor putitora)

As a part of conservation and mitigation measure, The PHPA-II signed a Letter of Understanding with Department of Livestock (DoL), under Ministry of Agriculture and Forest for construction of Golden Mahseer Hatchery and Conservation Facility at Harachu on 16^th March, 2018.

Subsequently, the construction work was awarded to Construction Development Corporation Limited (CDCL) comprising of the following works:

1. Two bailey bridges across Punatsangchhu and Harachhu.
2. Approach road and internal roads for hatchery facility and residential blocks.
3. Construction of two residential buildings.
4. Construction of hatchery viz office, laboratory, rearing unit, nursing unit and fish ponds.
5. Chain link fencing and installation of street lights.

Upon, completion of all the construction works, the hatchery was handed over to DoL, Ministry of Agriculture & Forest on 24^th March, 2021 for operation and maintenance.

Snow Trout Rearing facility at Rabuna, Wangdue

As a part of mitigation measures, snow trout rearing facility was set up at Rabuna, Wangdue for conservation of Snow Trout with ultimate aim of restocking the wild population in the main stream. The Snow Trout rearing facility at Rabuna was handed over to the Dzongkhag Livestock Sector under Wangdue Dzongkhag Administration on 30^th March, 2018.