NB/T 10347-2019Code for environmental impact assessment of hydropower projects (English PDF)

Foreword

This document was issued on 30 December 2019 by the National Energy Administration of the PRC and takes effect on 1 July 2020.

It is a NB/T standard: recommended rather than compulsory, but it is the text a Chinese reviewer applies when assessing a submission.

It is classified under ICS 27.140, Chinese classification P 59.

It replaces SDJ 302-88, which is superseded.

This code was revised by the drafting group in accordance with the requirements of the Notice of the National Energy Administration on Issuing the Second Batch of the 2012 Plan for the Formulation and Revision of Industry Standards in the Energy Field (Guo Neng Ke Ji [2012] No. 326). The revision was based on the environmental protection laws and regulations in force and on the requirements of the current technical standards for environmental impact assessment, and was carried out after extensive investigation and research, a careful summing-up of practical experience, reference to relevant advanced standards at home and abroad, and a wide solicitation of opinions.

The main technical contents of this code are: assessment classification and range; project investigation; engineering analysis and environmental impacts identification; investigation and assessment of environmental status; environmental impact forecasting and assessment; environmental protection measures and their techno-economic verification; environmental risk assessment and risk management; environmental monitoring plans; environmental management and supervision plans; environmental protection cost estimate and environmental impact cost-benefit analysis; and conclusion.

The main technical contents revised in this code are listed in the paragraphs below.

The compulsory provisions 1.0.1, 1.0.5 and 2.0.5 of the original code have been converted into recommendatory provisions.

A chapter of terms and a chapter on assessment classification and range have been added.

Chapters have been added on project investigation, engineering analysis, environmental protection measures and techno-economic verification, environmental risk assessment and risk management, environmental monitoring plans, environmental management and supervision plans, and environmental protection cost estimate and environmental impact cost-benefit analysis.

Appendix B to Appendix H and Appendix J have been added.

Original Appendix 1, Format and Requirements for Compiling the Work Outline of the Environmental Impact Assessment of Water Conservancy and Hydropower Projects, and original Appendix 3, Format for Compiling the Environmental Impact Report Form of Water Conservancy and Hydropower Projects and Instructions for Filling It In, have been deleted.

The general provisions, the investigation and assessment of environmental status, the environmental impact forecasting and assessment, and the conclusion have been revised.

Original Appendix 2 has been revised into Appendix A, Contents of Report on Environmental Impact Assessment of Hydropower Project.

This code is under the administration of the National Energy Administration. It was proposed by, and its day-to-day administration is the responsibility of, China Renewable Energy Engineering Institute. The interpretation of its specific technical contents is the responsibility of the Technical Committee for Standardization of Reservoir Environmental Protection in Hydropower Planning of the energy industry.

Comments and suggestions arising during implementation should be sent to China Renewable Energy Engineering Institute, No. 2 Liupukang Beixiaojie, Xicheng District, Beijing, postcode 100120.

Chief editing organizations: China Renewable Energy Engineering Institute; PowerChina Chengdu Engineering Corporation Limited.

Participating organizations: PowerChina Northwest Engineering Corporation Limited; PowerChina Zhongnan Engineering Corporation Limited; PowerChina Guiyang Engineering Corporation Limited.

The foreword lists thirty-three chief drafters, headed by Yu Weiqi, Liu Yuan, Li Yanong, Sun Dadong, Jiang Hong and Jiang Hao, and continuing with Wei Fan, He Tao, Yang Jiuxian, Lang Jian, Lu Bo, Tan Ping, Yan Jianbo, Kou Xiaomei, Qiu Xingchun, Li Min, Sun Dandan, Tong Xiaoshuang, Zhang Lei, Wang Chao, Wang Weiying, Chen Fan, Niu Le, Yang Wenzheng, Sun Ying, Long Xuezhen, Zhao Zaixing, Liu Rui, Wang Sungao, Xia Hao, Zhai Hongjuan, Zhang Yong and Ju Lin.

The foreword also lists twenty-three chief examiners, headed by Gu Hongbin, Wan Wengong, Chang Zhongnong, Chen Kaiqi, Xue Lianfang and Chen Guozhu, and continuing with Rui Jianliang, Cui Lei, Lian Yu, Chen Yongbai, Chen Yuying, Liu Qing, Li Yingxi, Wei Bing, Jin Yi, Zhang Rong, Chu Kaifeng, Shi Jiayue, Tang Zhongbo, Chen Xueqiang, Qiao Ye, Piao Ling and Li Shisheng.

Publication Data

Standard designation printed on the cover: NB/T 10347-2019, an energy industry standard of the People's Republic of China.

Chinese title on the cover: Shuidian Gongcheng Huanjing Yingxiang Pingjia Guifan. English title printed on the cover: Code for Environmental Impact Assessment of Hydropower Projects.

Classification codes printed on the cover: ICS 27.140 and the Chinese Standard Classification code P 59; the letter P also appears alone above the standard number.

Date of issue: 30 December 2019. Date of implementation: 1 July 2020. The title page repeats the date of entry into force as 1 July 2020.

This code replaces SDJ 302-88, as stated by the replacement note on the cover and on the title page.

Chief editing department indicated on the title page: China Renewable Energy Engineering Institute. Approving department: National Energy Administration. Issuing authority on the cover: National Energy Administration.

Publisher: China Water and Power Press, Beijing, 2020.

The code was approved by Announcement No. 8 of 2019 of the National Energy Administration, dated 30 December 2019, which approved 152 energy industry standards headed by the Code for Operation and Maintenance of Excitation Systems of Small Hydropower Generating Units, together with 39 English versions of energy industry standards headed by the Code for Safe and Civilized Construction of Onshore Wind Power Projects.

In the catalogue of industry standards attached to that announcement, this code appears as item 24, standard number NB/T 10347-2019, replacing SDJ 302-88, with date of approval 30 December 2019 and date of implementation 1 July 2020.

Structure of the Code

The code is organized in thirteen chapters followed by nine appendices and three closing items, and the body of the text runs to 59 pages before the explanation of provisions.

Chapters 1 and 2 set out the general provisions and the terms. Chapter 3, Assessment Classification and Range, is divided into nine sections covering general requirements, hydrological regime, water temperature, surfacewater quality, groundwater environment, aquatic ecosystem, terrestrial ecosystem, atmospheric environment and acoustical environment.

Chapter 4, Project Investigation, is divided into planning overview and project overview. Chapter 5, Engineering Analysis and Environmental Impacts Identification, is divided into general requirements, engineering analysis, analysis of environmental influence sources, environmental impact identification and assessment factor screening, and comprehensive analysis.

Chapter 6, Investigation and Assessment of Environmental Status, is the longest chapter of the first half of the code, with fifteen sections running from weather and climate to the comprehensive assessment of environmental status and including solid waste, public health, landscape and scenery and the environmental status of resettlement areas.

Chapter 7, Environmental Impact Forecasting and Assessment, has thirteen sections that follow the same sequence of environmental elements and close with the comprehensive analysis of environmental impacts.

Chapter 8, Environmental Protection Measures and Techno-Economic Verification, has fourteen sections, among them ecological operating schemes, ecological flow discharging measures, mitigation measures for water temperature impacts, water quality protection of the reservoir, environmental scientific research plans and the comprehensive analysis of environmental protection effects.

Chapters 9 to 12 cover environmental risk assessment and risk management, environmental monitoring plans, environmental management and supervision plans including the Three-Simultaneity management plans, and the environmental protection cost estimate together with the cost-benefit analysis. Chapter 13 sets out the conclusion.

The appendices supply the working tools of the assessment: Appendix A gives the contents of the environmental impact assessment report, Appendix B the table of major characteristics of the project, Appendix C the accounting of pollution source intensity, Appendix D the matrix for impact identification and assessment factor screening, Appendix E the tables of statistical data of runoff characteristic parameters, Appendix F the methods of surfacewater quality evaluation, Appendix G and Appendix H the methods and the result tables of hydrological regime influence forecasting, and Appendix J the methods of acoustical environment effect forecasting.

The code closes with the Explanation of Wording in This Code on page 57, the List of Quoted Standards on page 58 and the Addition, Explanation of Provisions, beginning on page 59.

1 Scope

NB/T 10347-2019 is the Chinese code for environmental impact assessment of hydropower projects, replacing SDJ 302-88. A dam changes the river it sits on - the flow regime below it, the sediment that no longer reaches the delta, the temperature of the released water, the fish that can no longer migrate past it, and the land and communities beneath the reservoir - and this code fixes how those changes are predicted, judged and mitigated before the project is approved. It sets the general provisions, the defined terms and the classification of assessment by project scale and environmental sensitivity, then the scope and the baseline survey required for each environmental element. Assessment chapters follow one by one: water environment including water temperature stratification and dissolved gas supersaturation, hydrology and the ecological flow to be released, sediment, aquatic ecology with particular attention to fish and their habitat and passage, terrestrial ecology and vegetation, soil erosion, groundwater, air quality and noise during construction, solid waste, and the social environment including resettlement and cultural heritage. For each the code gives the prediction method, the evaluation criteria and the mitigation measures to be designed, together with the environmental protection works that become part of the project. Risk assessment, the environmental management and monitoring plan, public participation, and the content of the assessment report complete the code.

1.0.1 This code is formulated in order to standardize the contents and the methods of the environmental impact assessment work of hydropower projects and to unify the technical requirements applied to it.

1.0.2 This code applies to the environmental impact assessment of newly built, rebuilt and expanded hydropower projects.

1.0.3 The environmental impact assessment of small hydropower projects may be carried out in a simplified manner in accordance with this code.

1.0.4 The environmental impact assessment of a hydropower project shall carry through the policy of overall planning with due consideration to all concerns, adaptation to local conditions and the pursuit of real effectiveness. It shall conform to the general requirements of the environmental protection laws, regulations and policies and of the environmental impact assessment of the river hydropower plan, shall follow the principles of objectivity and fairness, scientific rationality and concentration on the key points, and shall fully coordinate the relationship between hydropower development and ecological protection.

1.0.5 The environmental impact assessment of a hydropower project shall pay particular attention to the long-term, cumulative and regional impacts of the project on the hydrological regime, the water temperature, the surfacewater quality, the aquatic ecosystem and the terrestrial ecosystem, as well as to the impacts on environmentally sensitive objects. Where major environmental impacts may exist, special studies shall be carried out; where major environmental constraining factors exist, special verification shall be carried out.

1.0.6 The environmental impact assessment of a hydropower project shall conform to the relevant provisions of the current industry standards Technical Guidelines for Environmental Impact Assessment of Construction Projects, General Programme, HJ 2.1, and Technical Guidelines for Environmental Impact Assessment, Water Conservancy and Hydropower Projects, HJ/T 88, and shall mainly include the contents and requirements listed in the following items.

1.0.6 item 1 Collecting the existing relevant data and investigating the environmental status of the area that may be affected by the project.

1.0.6 item 2 Identifying the environmental impact factors, defining the environmental protection objectives and screening the assessment factors.

1.0.6 item 3 Determining the assessment classification and the assessment range.

1.0.6 item 4 Carrying out the analysis of the environmental rationality of the project schemes.

1.0.6 item 5 Forecasting and assessing the environmental impacts that the recommended project scheme may produce.

1.0.6 item 6 Putting forward the environmental protection measures and the environmental monitoring plans, and carrying out the cost-benefit analysis of the environmental impacts.

1.0.6 item 7 Putting forward the conclusions of the environmental impact assessment and compiling the environmental impact assessment documents. The contents of the environmental impact report of a hydropower project shall conform to the provisions of Appendix A of this code.

1.0.7 For the environmental impact assessment of a rebuilt or expanded project, the superimposed impacts that the environment may suffer after the rebuilding or expansion shall be forecast and assessed on the basis of the retrospective assessment of the environmental impacts of the existing project, and countermeasures shall be proposed for the treatment of the existing environmental pollution and ecological damage related to that project.

1.0.8 For projects where preparatory works such as the connection of road, power and water supply and the levelling of the site have already been carried out, an investigation shall be made of the implementation of environmental protection for those preparatory works. The investigation should mainly cover the design changes of the project scheme and their environmental rationality, the actual environmental impacts brought about by the project construction, and the implementation and the effects of the Three-Simultaneity system for environmental protection measures.

1.0.9 In addition to this code, the environmental impact assessment of hydropower projects shall also conform to the provisions of the relevant national standards in force.

2 Terms

2.0.1 Environmental impact of hydropower project. The impact on the environment of activities such as the construction and the operation of the hydropower project and the resettlement of the population, including direct and indirect impacts, favourable and unfavourable impacts, and reversible and irreversible impacts.

2.0.2 Environmentally sensitive object. The various kinds of natural and cultural protected areas, ecologically sensitive areas, areas of social concern, protected species and their important habitats, the various kinds of water intakes and the concentrated residential settlements that may be involved in a hydropower project.

2.0.3 Environmental protection objective. The environmental quality, ecological function, protection requirements for environmentally sensitive objects and other requirements related to environmental protection that shall be maintained during the construction and the operation of a hydropower project.

2.0.4 Cumulative impact. The superimposition in time and in space of the impacts on the hydrological regime, the water temperature, the aquatic ecosystem and other elements produced by the joint operation of the hydropower project with upstream and downstream cascade power stations or reservoirs, water transfer projects and similar works, and the environmental consequences thereby caused.

2.0.5 Hydrological regime. The temporal and spatial variation and the trend of the hydrological elements of a river, such as discharge, flow velocity, water level and sediment.

2.0.6 Water reduced reach. The river reach downstream of the dam site in which the discharge of the river channel is reduced as a consequence of water diversion for power generation by the hydropower project, usually the reach between the dam site and the tailwater of the power station.

2.0.7 Local climate. The climate of the small area in the reservoir region of a hydropower project that is affected by the changes in the underlying surface and in the conditions of heat and water transport of the water body; its characteristic elements mainly include air temperature and humidity.

2.0.8 Drawdown area. The belt of land along the banks of the reservoir inundation area that is exposed as a result of the periodic fluctuation of the water level during reservoir operation.

2.0.9 Ecological operating scheme. The modes of operation of the power station and of utilization of the reservoir adopted, through discharge regulation and sediment regulation, in order to maintain the ecological and environmental functions, improve the quality of the ecological environment and bring into play the ecological and environmental benefits, so as to satisfy requirements such as ecological water demand, environmental water demand, the control of saltwater intrusion at the river mouth and sediment transport.

3 Assessment Classification and Range

3.1.1 The environmental impact assessment of a hydropower project shall divide the assessment classes separately for each environmental element, according to the characteristics of the project, the environmental features of the area in which it is located and the degree of environmental sensitivity, and shall carry out the investigation and assessment work to the depth required by the corresponding class.

3.1.2 The environmental impact assessment of a hydropower project shall determine comprehensively the assessment range of each environmental element according to the characteristics of the project, the degree of impact, the distribution of the environmentally sensitive objects and the interaction among the impacts on the various related environmental elements, and shall draw the assessment range map using the national standard coordinate system.

3.2.1 The determination of the assessment class of the hydrological regime shall be carried out according to the scale of the affected river and the regulating performance of the reservoir, in accordance with the provisions of Table 3.2.1, Determination of the Assessment Class of the Hydrological Regime.

3.2.1 Table 3.2.1 classifies the affected river as large river, medium river or small river, and the regulating performance of the reservoir as annual regulation and above, seasonal regulation, and weekly regulation and below. A large river with annual regulation and above or with seasonal regulation gives class one and with weekly regulation and below gives class two; a medium river gives class one with annual regulation and above and class two in the other two cases; a small river gives class one with annual regulation and above, class two with seasonal regulation and class three with weekly regulation and below.

3.2.1 Note 1 to Table 3.2.1: a large river means a river whose mean annual discharge at the dam site is greater than or equal to 150 cubic metres per second.

3.2.1 Note 2 to Table 3.2.1: a medium river means a river whose mean annual discharge at the dam site is greater than 15 cubic metres per second and less than 150 cubic metres per second.

3.2.1 Note 3 to Table 3.2.1: a small river means a river whose mean annual discharge at the dam site is less than or equal to 15 cubic metres per second.

3.2.2 When a hydropower project presents one of the following situations, the assessment class of the hydrological regime shall be raised by one class.

3.2.2 item 1 When the hydropower project adopts the diversion type or the mixed type of development and thereby causes a reduction of the discharge in the river channel.

3.2.2 item 2 When there is a reservoir with seasonal regulation or with annual regulation and above upstream of the reservoir of the hydropower project, giving rise to superimposed impacts on the hydrological regime.

3.2.2 item 3 When the hydropower project affects the tidal reach of a large river and causes an upstream propagation of saltwater intrusion.

3.2.2 item 4 When the assessed water body involves an environmentally sensitive area.

3.2.3 The assessment range of the hydrological regime shall include the main stream and the tributaries of the reservoir region affected by the project, the river reach below the dam and the river reaches intended to be protected as fish habitats. Among these, the assessment range of the reach below the dam shall be determined comprehensively according to the regulating performance of the reservoir and according to the confluence of downstream tributaries, the construction and operation of power stations and the distribution of environmentally sensitive objects.

3.3.1 The determination of the assessment class of the water temperature shall be carried out according to the degree of water temperature sensitivity of the affected river and the type of water temperature distribution of the reservoir, in accordance with the provisions of Table 3.3.1, Determination of the Assessment Class of the Water Temperature. The type of water temperature distribution of the reservoir shall be identified in accordance with the provisions of the current industry standard Code for Calculation of Water Temperature of Hydropower Projects, NB/T 35094.

3.3.1 In Table 3.3.1 the water temperature sensitivity of the river is classified as sensitive or ordinary, and the type of water temperature distribution of the reservoir as stratified, transitional or mixed. A sensitive river gives class one for the stratified and the transitional types and class two for the mixed type; an ordinary river gives class one for the stratified type, class two for the transitional type and class three for the mixed type.

3.3.1 Note 1 to Table 3.3.1: sensitive means that within the assessment range there is a distribution of aquatic ecologically sensitive areas, important wetlands, water intakes of large and medium sized irrigation districts or other environmentally sensitive objects having special requirements as to water temperature. Note 2: ordinary means the situations other than sensitive.

3.3.2 The assessment range of the water temperature shall include the reaches of the main stream and of the tributaries in the reservoir region and the reach below the dam. Among these, the assessment range of the reach below the dam shall be determined comprehensively according to the type of water temperature distribution of the reservoir and according to the confluence of downstream tributaries, the construction and operation of power stations and the distribution of the objects sensitive to water temperature.

3.4.1 The determination of the assessment class of the surfacewater quality shall be carried out according to the pollution load level of the assessed river reach and the regulating performance of the reservoir, in accordance with the provisions of Table 3.4.1, Determination of the Assessment Class of the Surfacewater Quality.

3.4.1 In Table 3.4.1 the pollution load level of the assessed reach is classified as high, medium or low load. A high load gives class one for annual regulation and above and for seasonal regulation and class two for weekly regulation and below; a medium load gives class one for annual regulation and above, class two for seasonal regulation and class three for weekly regulation and below; a low load gives class three in all three cases.

3.4.1 Note 1 to Table 3.4.1: high load means that the waste water directly discharged by the point pollution sources along the banks of the assessed reach is greater than or equal to 20 000 cubic metres per day and that the permanganate index, the chemical oxygen demand, the total phosphorus and the ammonia nitrogen concentrations in the water quality of the assessed reach exceed the standard.

3.4.1 Note 2 to Table 3.4.1: medium load means the situations other than high load and low load. Note 3: low load means that the waste water directly discharged by the point pollution sources along the banks of the assessed reach is less than 200 cubic metres per day and that the permanganate index, the chemical oxygen demand, the total phosphorus and the ammonia nitrogen in the water quality of the assessed reach satisfy the environmental quality standard of the water body in which they are located.

3.4.2 When a hydropower project presents one of the following situations, the assessment class of the surfacewater quality shall be raised by one class: first, when the assessed reach involves a protected area of a drinking water source; second, when, on a river reach with medium or high pollution load, the hydropower project adopts the diversion type or the mixed type of development and thereby causes a reduction of the discharge in the river channel.

3.4.3 The assessment range of the surfacewater quality should be consistent with the assessment range of the hydrological regime.

3.5.1 The determination of the assessment class of the groundwater environment shall be carried out in accordance with the relevant provisions applicable to class three construction projects of the current industry standard Technical Guidelines for Environmental Impact Assessment, Groundwater Environment, HJ 610.

3.5.2 The assessment range of the groundwater environment shall include the distribution areas of the groundwater environmentally sensitive objects related to the project and shall be able to reflect the status of the regional groundwater environment and the characteristics of the basic flow field.

3.6.1 The determination of the assessment class of the aquatic ecosystem shall be carried out according to the aquatic ecological sensitivity of the affected river and the extent of the affected water area, in accordance with the provisions of Table 3.6.1, Determination of the Assessment Class of the Aquatic Ecosystem. The aquatic ecological sensitivity shall be determined in accordance with the relevant provisions of the current industry standard Technical Guidelines for Environmental Impact Assessment, Ecological Impact, HJ 19, by selecting the ecologically sensitive areas related to the protection of the aquatic ecosystem, the protected areas of aquatic germplasm resources being included among the important aquatic ecologically sensitive areas.

3.6.1 In Table 3.6.1 the aquatic ecological sensitivity is classified as special aquatic ecologically sensitive area, important aquatic ecologically sensitive area or ordinary area, and the extent of the affected water area is expressed by a reservoir area greater than or equal to 20 square kilometres or an affected river length greater than or equal to 100 kilometres, by a reservoir area greater than 2 square kilometres and less than 20 square kilometres or an affected river length greater than 50 kilometres and less than 100 kilometres, and by a reservoir area less than or equal to 2 square kilometres or an affected river length less than or equal to 50 kilometres. A special sensitive area gives class one in all three cases; an important sensitive area gives class one in the first two cases and class two in the third; an ordinary area gives class one in the first case and class two in the other two.

3.6.2 The assessment range of the aquatic ecosystem shall be determined comprehensively according to the range of the impacts of the changes in hydrological regime, water temperature and surfacewater quality, the range required for the fishes protected in the river basin in which the project is located to complete their life history, and the range of the impacts on the aquatic ecosystem. The key assessment range shall include the main stream and the tributaries of the river reach affected by the project and the river reaches intended to be protected as fish habitats.

3.7.1 The determination of the assessment class of the terrestrial ecosystem shall be carried out according to the terrestrial ecological sensitivity of the affected area and the area occupied by the reservoir inundation and by the project, in accordance with the provisions of Table 3.7.1, Determination of the Assessment Class of the Terrestrial Ecosystem. The terrestrial ecological sensitivity shall be determined in accordance with the relevant provisions of the current industry standard Technical Guidelines for Environmental Impact Assessment, Ecological Impact, HJ 19, by selecting the ecologically sensitive areas related to the protection of the terrestrial ecosystem.

3.7.1 In Table 3.7.1 the terrestrial ecological sensitivity of the affected area is classified as special terrestrial ecologically sensitive area, important terrestrial ecologically sensitive area or ordinary area, and the area of reservoir inundation and project occupation is classified as greater than or equal to 20 square kilometres, greater than 2 square kilometres and less than 20 square kilometres, and less than or equal to 2 square kilometres. A special sensitive area gives class one in all three cases; an important sensitive area gives class one, class two and class three respectively; an ordinary area gives class two, class three and class three respectively.

3.7.2 The assessment range of the terrestrial ecosystem shall include the reservoir inundation area, the affected area around the reservoir, the affected areas on both banks of the river reach below the dam, the construction area of the hydropower project, the resettlement area and the areas around the reservoir intended to be protected as habitats of protected species, and may be extended to a complete ecological unit according to the needs of the assessment. When the project involves a terrestrial ecologically sensitive area, that sensitive area shall be incorporated into the assessment range as a whole.

3.8.1 The assessment of the impacts of a hydropower project on the atmospheric environment should be carried out at the third class determined in accordance with the current industry standard Technical Guidelines for Environmental Impact Assessment, Atmospheric Environment, HJ 2.2.

3.8.2 The assessment range of the atmospheric environment shall include the area directly affected by the construction of the hydropower project and the distribution area of the objects sensitive to the atmospheric environment; the range should be 500 metres outward from the boundary of each construction working area, and 200 metres on each side of the centre line of the construction roads.

3.9.1 The determination of the assessment class of the acoustical environment shall be carried out in accordance with the relevant provisions of the current industry standard Technical Guidelines for Environmental Impact Assessment, Acoustical Environment, HJ 2.4.

3.9.2 The assessment range of the acoustical environment shall include the area directly affected by the construction of the hydropower project and the distribution area of the objects sensitive to the acoustical environment; the range should be 200 metres outward from the boundary of each construction working area, and 200 metres on each side of the centre line of the construction roads.

4 Project Investigation

4.1.1 The project investigation shall collect data on the natural geographical conditions of the river basin, such as topography and landforms, meteorology, river systems, runoff, floods and sediment characteristics, as well as data on the status of economic and social development.

4.1.2 The project investigation shall ascertain the hydropower plan of the river and the process of its examination and approval, the recommended planning scheme and the general situation of the opinions on the implementation of the plan, and the state of implementation of the plan, and shall collect the table of the techno-economic indexes of the recommended planning scheme, the map of the river system of the basin, the general layout plan of the plan and the longitudinal profile layout drawing.

4.1.3 The project investigation shall ascertain the environmental impact assessment of the river hydropower plan, the retrospective assessment of the environmental impacts of the hydropower development and the process of their examination, shall collect the assessment documents and the main conclusions of the opinions of their examination, and shall investigate the overall arrangement and the state of implementation of the environmental protection measures and the requirements imposed on the environmental protection of the project under assessment.

4.2.1 The project investigation shall collect the latest project design results at the stage of environmental impact assessment and technical documents such as the project feasibility study report, collecting in particular the data, figures and drawings related to environmental protection.

4.2.2 The investigation of the main project shall cover the basic conditions such as the geographical location, the development tasks, the necessity of construction, the comparison of project schemes, the project scale of the recommended scheme, the mode of development, the composition of the project, the project layout and the main structures, and shall collect or prepare the table of project characteristics, the table of project composition, the map of geographical location, the layout drawing of the hydropower complex and other drawings and tables. The table of major characteristics of a hydropower project shall conform to the provisions of Appendix B of this code.

4.2.3 The investigation of the construction planning of the project shall cover the construction diversion, the general construction layout, the permanent and temporary land occupation for construction, the construction plant facilities, the construction transport, the planning of the borrow areas, the planning of the spoil disposal areas, the construction technology, the main project quantities and the general construction schedule, and shall collect drawings such as the drawing of the external transport for construction and the general construction layout drawing.

4.2.4 The investigation of the initial impoundment plan of the reservoir shall cover the period of initial impoundment of the reservoir, the types, layout schemes and discharge capacity of the various discharge facilities, the water level of initial impoundment and the discharge released downstream.

4.2.5 The investigation of the operation scheme of the project shall cover the modes of operation of the reservoir and of the power station, the variation of the reservoir water level in a typical year and on a typical day, the processes of inflow and outflow discharge, and the water level and discharge relation curves at the design sections of the project.

4.2.6 The investigation of the resettlement planning shall cover the physical indexes within the land requisition range of the construction area, broken down by administrative division, and the state of the rural resettlement, of the relocation of towns and cities, of the treatment of specialized projects and of the clearing of the reservoir bottom, and shall collect drawings such as the map of the reservoir inundation range, the resettlement planning drawing, the general layout plan of the residential settlements to be built, the general layout plan of the relocation of towns and cities and the general layout plan of the reconstruction planning of the specialized projects.

4.2.7 The investigation of the environmental protection situation of the project shall cover the project items having an environmental protection function in the hydropower complex and in the resettlement planning and design, the environmental protection measures already adopted and their effects.

4.2.8 The investigation of a rebuilt or expanded project shall collect the project characteristics of the original project, such as its project composition and main economic indexes, shall investigate the environmental protection measures already adopted and their effects, and shall investigate the construction contents of the project to be built and its relations of dependence on the original project.

4.2.9 The investigation of preparatory works such as the connection of road, power and water supply and the levelling of the site shall ascertain the composition of such works and their relations of dependence on the main project, shall collect the environmental impact assessment documents of those works and the opinions of their examination and approval, and shall investigate the state of implementation of the works, the design changes of the project scheme, and the environmental protection measures already adopted and their effects.