Chapter 1: introduction
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- Bu səhifədəki naviqasiya:
- 5.8 Associated Risks
- 5.9 Technology, Operation, Procedures, Time Schedules and Raw Materials to be used
- Chapter VI: POTENTIAL ENVIRONMENTAL IMPACTS AND MITIGATION MEASURES
- 6.1 Adverse Issues
5.7 No Forest AlternativeThe forest guideline 2006 of the GoN mandates no forest alternative as one of the criteria for the project site selection to minimize forest losses. To comply with the guideline provisions, one of the considerations while selecting the project structure and project support facility sites is to minimize the forest areas as far as possible. The selected structure and ancillary facility sites locations (refer section 5.6 above) are the locations which impose the least impacts on the forest and are the most suitable locations from the power output and geological/ geotechnical stability prospective. The selected site is therefore considered to have insignificant impacts on the area green cover. 5.8 Associated RisksThe project design was given a due consideration to avoid risks both in terms of natural and social resources. While doing so, the efforts were made to minimize the project’s costs. Most of the waterways in KAHEP have been designed as the underground structures including settling basin, headrace tunnel and surge shaft. The underground settling basin and headrace tunnel was designed based on the surface geological investigations and has the risks associated with the cost overrun during the construction due to possible changes in the geological formations properties. Similarly, the powerhouse area is located partly on an elevated terrace of the Tamor River and the fan deposit of Piple Khola. It was designed considering 1,000 years return period flood level of Tamor River. The risk of GLOF has also been considered by referring to the potential GLOF discharge estimates. Protection structures were designed for two extreme floods with the assumption that both of them will not occur simultaneously. Even though the risk associated with GLOF is not prevalent in the Tamor basins as per a recent study on GLOF by ICIMOD (2001), there is a potential hazard of flooding of the powerhouse in an extreme case due to the lack of data on GLOF events. Protection structures to safeguard the powerhouse have been envisaged from the undercutting and sediment deposition from the Piple Khola torrent. The Piple Khola has been cutting and depositing sediment loads in the vicinity of the powerhouse area in the past. The proposed protection structure assumed to avoid the risk of such events. Another major item to consider is the risk of the peaking reservoir. A reservoir with the designed storage capacity is not envisaged to pose risks to the downstream population and other natural and environmental resources in the event of normal operation. However, risks due to improper regulation, malfunctioning of regulation structures and dam breaking, at the worst, may pose threats to the downstream reaches. Preliminary calculations show that the spontaneous discharge due to dam breaking is 1084.1 m3/s at FSL 575.3 m and 1217.931 m3/s at FSL 578.3 m that is much lower than the design flood of 1860m3/s at Q100. Therefore, the risk of inundating the downstream even during a dam break event is low. Still, the ponding reservoir and its regulation might have the consequences and pose some risks, like discharging water to the downstream without adequate warning which may sweep humans and cattle on the downstream reach. An adequate warning system should be designed to minimize such avoidable risks. 5.9 Technology, Operation, Procedures, Time Schedules and Raw Materials to be usedTo provide the maximum job opportunities to the locals, the selected construction technology alternative is based on a mix of labor and machine. The machine only or maximum machine based construction technology is rejected because of its potential environmental management difficulties and the minimum job opportunities to the locals. The power plant operation will make the optimal utilization of the available hydrology. A consideration is given to the environmental requirements to release the environmental flow from the dam according to the local legal provisions. As far as possible, raw materials required for the project will be sourced from the local area except for timber and fuel wood. Chapter VI: POTENTIAL ENVIRONMENTAL IMPACTS AND MITIGATION MEASURESThis Chapter discusses the environmental issues identified during the ToR stage of the study for the prediction of the potential environmental impacts in the project area in the absence of mitigation measures. The section also identifies the mitigation measures to avoid, minimize, and compensate the adverse environmental impacts with additional enhancement measures to maximize the benefits of the positive impacts. The project proponent is committed to the implementation of all mitigation and enhancement measures illustrated in this section at different phases of project implementation and operation. The proponent understands that any additional measures required to avoid, minimize and compensate the adverse environmental effect unforeseen in this section are also its responsibility. 6.1 Adverse IssuesThe prioritized adverse issues that are likely to occur by the implementation of the project are presented below. 6.1.1 Primary Issues6.1.1.1 Construction PhaseI. Impacts on vegetation due to the site clearance for the project activities and offsite activities of construction works and associated workforce a. Loss of Forest and Site Clearance for Project Structures and Facilities The site clearance activities, for the construction of project structures (such as headworks, tunnel inlet, surge-shaft, penstock & powerhouse) and project facilities will result in the loss of vegetation as parts of these structures and facilities are situated in forest lands. The forestlands to be acquired are small areas scatted in several locations for various project works. Out of total 1.57 ha forest land required, 0.21 ha area belongs to Thulo Dhuseni Community Forest (CF), 0.12 ha belongs to Kabeli Garjite CF, 0.97 ha belongs to Pinasi Leasehold Forest (LF) and 0.27 is the communal national forest land. Table 6.1 presents the loss of forest areas by the construction of different project structures and facilities. Table 6.1: Loss of Forest Vegetation in Different Project Structures and Facilities
Note: As the internal access roads have an existing community developed motorable track, the forest clearance is not envisaged. Similarly, quarry sites, camps and spoil disposal site lie outside the forested areas. Source: Field Survey, 2010 The loss of tree species, pole, sapling and seedling in the different forest areas is presented in Table 6.2. Table 6.2: Loss of Forest Resources in Different Forest Areas by KAHEP Forest Land Acquisition
Note: Se-Seedling, Sa-Sapling, P-Pole, T-Tree; TS-Total Stem, TB-Total Branch, TF-Total Foliage * Avg. DBH and Range of DBH to be given for Pole and Tree Class ** Seedling_0-4 cm DBH; Sapling_4-10 cm DBH; Pole Class_10-30 cm DBH; Tree Class_>30 cm DBH Source: Field Survey, 2010 It is estimated that a total of 200 trees and 153 pole size vegetation would be cleared from the forest land areas occupied by the project permanent structures and facilities. None of the floral species to be cleared by the project in the occupied forestlands are listed in the IUCN Red Book or CITES Appendices. The Government of Nepal, under the Forest Act 1993, has protected many plant species which are banned for transportation, export and felling for commercial purposes. In the project impact area, there are some floral species listed by the Government of Nepal as protected based on their economic value. Table 6.3 presents the list of the floral species “protected” under Forest Act and available in the project impact zones that would have to be cut for the construction of the project. All of the protected species are the commonly found species within the project area. Table 6.3: Loss of GON Protected Floral Species in the Forestland Occupied by the Project
Note: Se-Seedling, Sa-Sapling, P-Pole, T-Tree Source: FieldSurvey, 2010 It is estimated that 102 trees and 61-pole size vegetation of GON protected category will be cleared from the forestland areas occupied by the project. Cutting/ clearing of the protected species for commercial purpose is not permissible. However, cutting/ clearing of these species for non-commercial/ development purpose is allowed and a subject to clearance from the competent authority (i.e. Ministry of Forest and Soil Conservation), and compensatory plantation at the ratio of 1: 25 (i.e. 1 tree cut: 25 sapling planted and taken care for 5 years at the least). The clearance of forest in monetary terms is valuated in Table 6.4. A total of NRs 2,228,293 is the estimated monetary value of the lost forest area resources. Table 6.4: Monetary Value of the Lost Forest Resources
Note: Pole Ku Kath = NRs. 250/pole, Su kath NRs 450/pole; Timber, Ku Kath - NRs 125/cft (NRs.4411.25/ cum), SuKath NRs 350/cf (NRs.12351.50/cum) [Sukath- Acacia catechu, Adina cordifolia, Duabanga grandiflora, Shorea robusta]; Fuel Wood - Lumpsum NRs 11500/Chatta; Fodder - Lumpsum NRs 0.5/kg Source: EIA Survey, 2010 As elaborated in the baseline environment (Chapter 4, section 4.2.1.8), the forest in the project area is degraded and encroached by the local communities for cattle grazing and collection of firewood, fodder, and litter, and hence it has lost the characteristics of a natural forest. Though the community forest is better preserved than a government forest, it has very little or limited significance for wildlife habitat. Despite this fact, these degraded forest patches have provided ecological services (groundwater recharge, soil moisture, spring flows, soil nutrient budget etc.) to sustain the agro-economic practices. The loss of 1.57 ha forest due to the project is scattered in several locations and occurs only along the boundary areas of the existing forest and does not involve large scale fragmentation across the core forested area. In addition, the road leading to the headworks developed by the local communities already has some adverse implications due to forest fragmentation at outer boundaries of the forest and erosion compared to other areas of forest losses. Considering the occasional nature of the wildlife (mostly raider animals) movement (for feeding only) across these areas the envisaged impact is assessed as insignificant, because the raider wildlife have already established an ecological relationship with the agro-economic activities of the nearby communities.
Enormous efforts have been made to minimize the forest area and vegetation loss while planning the project structures and facilities. However, complete avoidance of the forested areas and vegetation is not possible due to the key structural locations of the project, which are largely determined by geology and other design parameters. It is, therefore, in the given geographic setting, some small loss of the forested area and vegetation by the project structures and facilities is unavoidable. However, to minimize the loss of forest area and vegetation and to mitigate the impacts, the following abatement measures, already agreed with local communities, will be implemented in the project VDCs.
b. Loss of vegetation due to the offsite activities of construction works and associated workforce The project development site at headworks and powerhouse will have the presence of a relatively large construction workforce both local as well as outsiders. Nearly 600 to 800 people will be in the project site during the peak construction period (which is normal for a project of this magnitude in Nepal such as the Middle Marsyagdi Project). Traditionally for cooking and other heating purposes, firewood is used in Nepal. If no other alternatives are offered, the construction workers in the Kabeli project will also use the firewood for cooking. The obvious sources of the firewood are the local forests. The local forests have a limited regeneration capacity to meet the required firewood annually. The construction work force family or the local merchants/villagers are likely to cut the trees from the local forest to supplement the firewood requirement of the construction workforce. This might have a long-term impact on the ecological goods and services provided by the forest if not mitigated properly. The experience in other hydropower projects recently developed shows that many of the outside workers do not cook their food themselves and were dependent upon the nearby hotels and restaurants opened by outsiders or the locals to grab the economic opportunity (Consultant’s Middle Marsyangdi HEP experience). The hoteliers, as they burden the energy cost of cooking to the consumer, prefer LPG gas for cooking and cause very little damage to the forest areas for cooking purposes. This might be the case in the proposed project as it is facilitated with motorable road and people are already habituated to using LPG stoves for cooking. But one cannot be sure about the likely impacts based on the experience in other socio-economic setting and hence the environmental impacts of the associated project workforce could not be overlooked. Non-Timber Forest Products (NTFPs) are available in the upper reaches of the surrounding forests, which are away from the project facility sites. Although there will be no direct impacts on the NTFPs by project facility, possibility of increased demand or induced impact on the NTFP due to increased number of people during construction may not be ruled out. Mitigation
Despite the above measures, there will be some residual ecological effects of forest clearance for the structures and facilities and will remain as residual impact for a period of 20 to 30 years till the afforested forest matures. c. Impacts on protected species of flora and fauna None of the floral species to be cleared by the project, in the occupied forestlands, are listed in the IUCN Red Book or CITES Appendices. The GON protected plant species namely Shorea robusta, Bombax ceiba and different species of lichens & orchids attached on the trunks and branches of the trees to be cleared will be affected by the construction of project structures and facilities. The impact to the protected species of flora (pole and tree) is considered low, as listed species are categorized as protected on economic grounds only (Table 6.4). The project development site is not the prime habitat of the conservational or economical important mammals or any other animal life. However few wild mammals visit the project development area for different purposes- perhaps the area is used as alternate seasonal migratory route, occasional feeding purpose, or temporary habitat for socially driven animals12, etc. The baseline study finding reveals that the project affected sites are the occasional feeding grounds particularly of the raider mammals. Nonetheless, the loss of 1.57 ha forest due to the project is scattered in several locations and does not involve large scale fragmentation across the core forested area; this impact is not envisaged to be significant.
The last three measures will be included in the specifications for the Contractor and in the Code of Conduct for workers. d. Impact on the community and leasehold forests due to construction of dam, access road and powerhouse structures The project is only acquiring 1.1 % (0.21 ha out of total 19 ha) forest land of Thulo Dhuseni CF; and 0.32% (0.12 ha out of total 36.5 ha) forest land of Kabeli Garjite CF along the boundary areas at the headwork site. The acquisition of forest lands are in small pieces on the edges of the forest areas and will not create fragmentation across the core-forested area. Therefore, the loss of community forest to the user group is not considered significant. Apart from that, the construction of powerhouse, switchyard and penstock will result in the loss of 0.97 ha of leasehold forest which belongs to the seven local inhabitants of Pinase village. As this forest is already in a degraded condition and there are options of other community forests to these users, the impact on the leasehold forest is not considered significant, while the quarry area, camps, and spoil disposal sites will not affect the forest.
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