Environmental Impact Assessment Ordinance (Cap. 499), Section 5 (7)
Environmental Impact Assessment Study Brief No. ESB-134/2005
(hereinafter known as the "Project")
Name of Applicant : Castle Peak Power Company Limited,
CLP Power Generation Projects Department,
Black Point Power Station,
G/F East Wing, GBG Management Building
Lung Kwu Tan, Tuen Mun, N.T.
(hereinafter known as the "Applicant")
1. BACKGROUND
1.1 An application (No. ESB-134/2005) for an Environmental Impact Assessment (EIA) study brief under section 5(1) of the Environmental Impact Assessment Ordinance (EIAO) was submitted by the Applicant on 28 September 2005 with a project profile (No. PP-262/2005) (the Project Profile).
1.2 The scope of the Project is to construct and operate emissions control at Castle Peak Power Station “B” Units (CPB) , as shown in Figures 1 and 2 in Appendix A and described below :
(i) Demolition of existing facilities at CPB including the 4680 tonne Fuel Oil Day Tank, Fuel Oil Pump House, Ash Plant Substation, Ash and Dust Control Room, and Dangerous Goods (DG) Store;
(ii) Relocation or re-routing of existing facilities including Underground Pipeworks, 2626 litre Carbon Dioxide (CO2) Storage Tank, 2 numbers of 4600 litre Liquefied Petroleum Gas (LPG) Storage Tank, Intermediate Pressure Reduction Station, Oil Interceptors, Oils Sump, Oil Sewer Manholes and Foul Water Pumping Station;
(iii) Installation of new emission control equipment and facilities including the Selective Catalytic Reduction (SCR) for NOx emission control, Limestone Flue Gas Desulphurisation (LS-FGD) for SO2 emission control;
(iv) Provision of Reagent and By-Product Handling and Storage Facilities including limestone silos, limestone slurry tanks, gypsum dewatering and storage facilities for the LS-FGD operations and the urea storage silos, urea dissolving tanks, urea solution storage tanks and urea-to-ammonia reactors for the SCR operations;
(v) Provision of additional berthing facilities for loading and unloading of the additional reagents, including up to 40,000 tonnes per year of urea, 150,000 tonnes per year of limestone and by-products including 257,000 tonnes per year of gypsum.
1.3 The Project is a Material Change to the existing Castle Peak Power Station, which is an exempted designated project (DP), because of the changes introduced by the SCR and LS-FDG operations to the types and quantities of wastes, emissions and effluents. In addition, the Project has or is likely to have other DP elements under Schedule 2 of the EIAO, including :
(i) Item 16 in Part 2 – Decommissioning of a store for oil with a storage capacity exceeding 200 tonnes;
(ii) Item C12 in Part 1 - A dredging operation which is less than 100 m from a seawater intake point;
(iii) Item G6 in Part 1 - A waste disposal facility for gypsum;
(iv) Item K6 in Part 1 - A chemical plant with a storage capacity of more than 500 tonnes and in which substances are processed or produced.
1.4 Pursuant to section 5(7)(a) of the EIAO, the Director of Environmental Protection (the Director) issues this EIA study brief to the Applicant to carry out an EIA study.
1.5 The purpose of this EIA study is to provide information on the nature and extent of environmental impacts arising from the construction and operation of the Project and related activities that take place concurrently. This information will contribute to decisions by the Director on :
(i) the overall acceptability of any adverse environmental consequences that are likely to arise as a result of the Project;
(ii) the conditions and requirements for the detailed design, construction and operation of the Project to mitigate against adverse environmental consequences wherever practicable; and
(iii) the acceptability of residual impacts after the proposed mitigation measures are implemented.
2. OBJECTIVES OF THE EIA STUDY
2.1 The objectives of the EIA study are as follows :
(i) to describe the Project and associated works together with the requirements for carrying out the Project;
(ii) to identify and describe elements of community and environment likely to be affected by the Project and/or likely to cause adverse impacts to the Project, including natural and man-made environment and the associated environmental constraints;
(iii) to provide information on the consideration of alternatives to avoid and minimize potential environmental impacts to ecologically sensitive areas and other sensitive uses; to compare the environmental benefits and dis-benefits of each of different options; to provide reasons for selecting the preferred option(s) and to describe the part environmental factors played in the selection of preferred option(s);
(iv) to identify and quantify emission sources and determine the significance of impacts on sensitive receivers and potential affected uses;
(v) to identify and quantify any potential landscape and visual impacts and to propose measures to mitigate these impacts;
(vi) to identify and quantify any potential losses or damage to flora, fauna and natural habitats and to propose measures to mitigate these impacts;
(vii) to propose the provision of mitigation measures so as to minimize pollution, environmental disturbance and nuisance during construction and operation of the Project;
(viii) to investigate the feasibility, practicability, effectiveness and implications of the proposed mitigation measures;
(ix) to identify, predict and evaluate the residual environmental impacts (i.e. after practicable mitigation) and the cumulative effects expected to arise during the construction and operation phases of the Project in relation to the sensitive receivers and potential affected uses;
(x) to identify, assess and specify methods, measures and standards, to be included in the detailed design, construction and operation of the Project which are necessary to mitigate these environmental impacts and cumulative effects and reduce them to acceptable levels;
(xi) to investigate the extent of the secondary environmental impacts that may arise from the proposed mitigation measures and to identify constraints associated with the mitigation measures recommended in the EIA study, as well as the provision of any necessary modification; and
(xii) to design and specify environmental monitoring and audit requirements to ensure the effective implementation of the recommended environmental protection and pollution control measures.
3. DETAILED REQUIREMENTS OF THE EIA STUDY
3.1 The Purpose
The purpose of this study brief is to scope the key issues of the EIA study. The Applicant has to demonstrate in the EIA report that the criteria in the relevant sections of the Technical Memorandum on the Environmental Impact Assessment Process of the Environmental Impact Assessment Ordinance (hereinafter referred to as “the TM”) are complied with.
3.2 The Scope
3.2.1 The scope of this EIA study shall cover the Project mentioned in sub-section 1.2 above. The EIA study shall address the likely key issues described below, together with any other key issues identified during the course of the EIA study:
(i) potential air quality and noise impacts from construction and operation of the Project to nearby sensitive receivers, taking into account the cumulative impact from the existing and planned sources of pollution in the vicinity of the Project;
(ii) potential water quality impact from the construction and operation of the Project on the relevant water system(s);
(iii) potential losses or damage to flora, fauna and natural habitats and the potential ecological impacts from the Project;
(iv) waste arising as a result of the construction and operation activities of the Project, including the management of dredged marine sediment; and
(v) potential land contamination from demolition, relocation or re-routing of existing facilities.
3.3 Consideration of Alternatives
3.3.1 The Need of the Project
The Applicant shall study and review the need of the Project, and provide information to justify the need. The Applicant shall explain clearly the purpose and objectives of the Project and describe the scenarios with and without the Project.
3.3.2 Consideration of Different Technology and Emission Controls Options
In addition to the proposed SCR and LS-FDG processes mentioned in sub-section 1.2 above, the Applicant shall consider other feasible emission controls options for the Project, provide justification regarding how the proposed scheme is arrived at, including the descriptions of the environmental factors considered in the option selection. Alternative emission controls options and selection of the most suitable technology shall be reviewed and investigated. A comparison of the environmental benefits and dis-benefits of possible emission controls options and alternative technologies and design shall be made with a view to recommending the preferred option to maximise environmental benefits and avoid/minimize adverse environmental effects to the maximum practicable extent.
3.3.3 Consideration of Alternative Construction Methods and Sequences of Works
Taking into consideration the combined effect with respect to the severity and duration of the construction impacts to the affected sensitive receivers, the EIA study shall explore alternative construction methods and sequences of works for the Project, with a view to avoid prolonged adverse environmental impacts to the maximum practicable extent. A comparison of the environmental benefits and dis-benefits of applying different construction methods and sequence of works shall be made.
3.3.4 Selection of Preferred Scenario
Taking into consideration of the findings in sub-sections 3.3.2 and 3.3.3 above, the Applicant shall recommend/justify the adoption of the preferred scenario that will maximise environmental benefits and avoid or minimize adverse environmental effects arising from the Project, and adequately describe the part that environmental factors played in arriving at the final selection.
3.4 Technical Requirements
The Applicant shall conduct the EIA study to address environmental aspects as described in sub-sections 3.1, 3.2 and 3.3 above. The EIA study shall include the following technical requirements on specific impacts.
3.4.1 Air Quality Impact
3.4.1.1 The Applicant shall follow the criteria and guidelines as stated in Section 1 of Annex 4 and Annex 12 of the TM for evaluating and assessing the air quality impact due to the construction and operation of the Project, as stipulated in Sections 1.2 and 1.3 above.
3.4.1.2 As stipulated in Section 1.2 above, the Project is for reducing the overall NOx and SO2 emission from the Castle Peak Power Station “B” Units. The Applicant may carry out a comparative study to demonstrate if the stack emission impacts of the “B” Units before and after the Project will lead to lower air quality impacts at the Air Sensitive Receivers (ASRs) including the areas of Tuen Mun, Lung Kwu Tan, Ha Pak Nai, Sheung Pak Nai, Tin Shui Wai, So Kwun Wat, Tai Lam Chung and Tung Chung by using either a simple screening tool such as ISCST3 Gaussian model or a more sophisticated tool, such as wind tunnel test, if necessary. If result of the comparative study shows that the air quality impacts at ASRs are worsened, the air quality impact assessment following the technical requirements as described in Section 3.4.1.5 below shall be carried out to evaluate the cumulative impacts at the identified ASRs against the criteria set out in section 1 of Annex 4 of the TM. The cumulative assessment for the stack emission impact shall take into account the project specific impacts together with a regional-wide emission impact for background concentration.
3.4.1.3 The Study Area for air quality impact assessment shall generally be defined by a distance of 500 metres from the boundary of the Project site, and it shall be extended to include other areas that may have a bearing on the environmental acceptability of the Project. For this Project, the assessment shall include the existing and planned/committed air sensitive receivers within the study area, areas of Tuen Mun, Lung Kwu Tan, Ha Pak Nai, Sheung Pak Nai, Tin Shui Wai, So Kwun Wat, Tai Lam Chung and Tung Chung, where the air quality may be potentially affected by the Project. Such assessment shall be based on the best available information at the time of the assessment.
3.4.1.4 The Applicant shall assess the air pollutant concentrations with reference to the Guidelines for Local-Scale Air Quality Assessment Using Models given in Appendices B1 – B3 or other methodology as agreed by the Director.
3.4.1.5 The air quality impact assessment shall include the following:
(i) Background and Analysis of Activities
(a) Provide background information relating to air quality issues relevant to the Project, e.g. description of the types of activities of the Project that may affect air quality during operation stage.
(b) Present background air quality levels in the assessment area for the purpose of evaluating cumulative operational air quality impacts.
(c) Consider alternative modes of operation to minimize the operational air quality impact.
(ii) Identification of Air Sensitive Receivers (ASRs) and Examination of Emission/ Dispersion Characteristics
(a) Identify and describe representative existing and planned/committed ASRs, such as the proposed Tung Wah Group of Hospital Youth Holiday Camp at Siu Lang Shui, that would be affected by the Project, including those earmarked on the relevant Outline Zoning Plans, Development Permission Area Plans, Outline Development Plans and Layout Plans. The Applicant shall select the assessment points of the identified ASRs such that they represent the worst impact point of these ASRs. A map showing the location and description including name of buildings, their uses and height of the selected assessment points shall be given. The separation distances of these ASRs from the nearest emission sources shall also be given.
(b) Provide an exhaustive list of air pollutant emission sources within the Castle Peak Power Station which are to have impact related to the Project based on the analysis of the operational activities in Section 3.4.1.5(i) above. Apart from stack emissions, it is also necessary to address any air quality issue due to additional marine traffic emissions for transportation of materials including limestone and gypsum. Besides, if the likely concurrent projects are identified relevant, its possible emissions shall also be taken into account in the air quality impact assessment. Confirmation of the validity of the assumptions and the magnitude of the activities shall be obtained from the relevant parties and documented.
(c) Describe any topographical and man-made features that may affect the dispersion characteristics of the area.
(iii) Operational Phase Air Quality Impact
(a) The Applicant shall assess the expected air pollutants, including gaseous emissions and dust, at the identified ASRs based on an assumed reasonably worst-case scenario. The evaluation shall be based on the strength of the emission sources identified in Section 3.4.1.5(ii)(b) above. The Applicant shall follow the methodology as described in Section 3.4.1.5 (iv) below when carrying out the quantitative assessment.
(iv) Quantitative Assessment Methodology
(a) In choosing the types of models (such as physical or numerical) to be used for quantitative assessment of the operational phase air quality impact, the Applicant shall apply the general principles enunciated in the modelling guidelines in Appendices B-1 to B-3 while making allowance for the specific characteristics of the Project. The specific methodology must be documented in such level of details (preferably with tables and diagrams) to allow the readers of the assessment report to grasp how the model is set up to simulate the situation at hand without referring to the model input files. Details of the calculation of the emission rates of air pollutants for input into the modelling shall be presented in the EIA report. The Applicant must ensure consistency between the text description and the model files. In case of doubt, prior agreement between the Applicant and the Director on the specific modelling details should be sought.
(b) The Applicant shall identify the key/representative air pollutant parameters (types of pollutants and the averaging time concentration) to be evaluated and provide explanation for choosing these parameters for the assessment of the impact of the Project.
(c) If the predicted air quality impacts at the ASRs are worsened by the Project, the Applicant shall calculate the cumulative air pollutant concentrations at the identified ASRs identified under Section 3.4.1.5(ii) above and compare these results against the criteria set out in Section 1 of Annex 4 in the TM. The predicted air quality impacts (both unmitigated and mitigated) shall be presented in the form of summary table and pollution contours as appropriate, to be evaluated against the relevant air quality standards and on any effect they may have on the land use implications. If applicable, plans of a suitable scale should be used to present pollution contour to allow buffer distance requirements to be determined properly.
(v) Mitigation Measures for Non-compliance
The Applicant shall propose remedies and mitigating measures where the predicted air quality impact exceeds the criteria set in Section 1 of Annex 4 in the TM. If these measures will result in any constraints on future land use planning outside the Project site, the Applicant shall liaise with the relevant government departments/authorities and document the agreement in the EIA Report in order to demonstrate that the proposed measures are feasible and practicable. The Applicant shall demonstrate quantitatively that the residual impacts after incorporation of the proposed mitigating measures will comply with the criteria stipulated in Section 1 of Annex 4 in the TM.
(vi) Submission of Model Files
Input and output file(s) of the model run(s) shall be submitted to the Director in electronic format.
(vii) Constructional Phase Air Quality Impact
The Applicant shall follow the requirements of the Air Pollution Control (Construction Dust) Regulation to ensure constructional dust impacts are controlled within the relevant standards as stipulated in section 1 of Annex 4 of the TM. An audit and monitoring program during constructional stage shall be devised to verify the effectiveness of the control measures and to ensure that the construction dust levels be brought under proper control. The Applicant shall follow the methodology set out in subsection 3.4.1.7 (iv) above when carrying out the quantitative assessment.
3.4.2 Noise Impact
3.4.2.1 The Applicant shall follow the criteria and guidelines for evaluating and assessing noise impact as stated in Annexes 5 and 13 of the TM, respectively.
3.4.2.2 The noise impact assessment shall include the following :
(i) Determination of Study Area
The study area for the noise impact assessment shall generally include areas within 300m from the Project boundary. Subject to the agreement of the Director, the study area could be reduced accordingly if the first layer of noise sensitive receivers (NSRs), closer than 300m from the outer Project limit, provides acoustic shielding to those receivers at distances further away from the Project. Subject to the agreement of the Director, the study area shall be expanded to include NSRs at distances over 300m from the Project which would be affected by the construction and operation of the Project.
(ii) Provision of Background Information and Existing Noise Levels
The Applicant shall provide background information relevant to the Project, e.g. relevant previous or current studies. Unless required for determining the planning standards, e.g. those for planning of fixed noise sources (such as ventilation systems of traffic noise enclosures), no existing noise levels are particularly required.
(iii) Identification of Noise Sensitive Receivers
(a) The Applicant shall refer to Annex 13 of the TM when identifying the NSRs. The NSRs shall include existing NSRs and planned/committed noise sensitive developments and uses, such as the proposed Tung Wah Group of Hospital Youth Holiday Camp at Siu Lang Shui, earmarked on the relevant Outline Zoning Plans, Development Permission Area Plans, Outline Development Plans, Layout Plans and other relevant published land use plans. Photographs of existing NSRs shall be appended to the EIA report.
(b) The Applicant shall select assessment points to represent identified NSRs for carrying out quantitative noise assessment described below. The assessment points shall be agreed with the Director prior to the quantitative noise assessment. A map showing the location and description such as name of building, use, and floor of each and every selected assessment point shall be given. For planned noise sensitive land uses without committed site layouts, the Applicant should use the relevant planning parameters to work out representative site layouts for operational noise assessment purpose.
(iv) Provision of an Emission Inventory of the Noise Sources
The Applicant shall provide an inventory of noise sources including representative construction equipment for construction noise assessment, and traffic flow/ fixed plant equipment (e.g. ventilation systems of traffic noise enclosures), as appropriate, for operational noise assessment. Confirmation of the validity of the inventory shall be obtained from the relevant government departments/authorities and documented in the EIA report.
(v) Construction Noise Assessment
(a) The assessment shall cover the cumulative noise impacts due to the construction works of the Project and other concurrent projects identified during the course of the EIA study.
(b) The Applicant shall carry out assessment of noise impact from construction (excluding percussive piling) of the Project during daytime, i.e. 7 a.m. to 7 p.m., on weekdays other than general holidays in accordance with the methodology in paragraphs 5.3. and 5.4 of Annex 13 of the TM. The criteria in Table 1B of Annex 5 of the TM shall be adopted in the assessment.
(c) To minimize the construction noise impact, alternative construction methods to replace percussive piling shall be proposed as far as practicable.
(d) If the unmitigated construction noise levels are found exceeding the relevant criteria, the Applicant shall propose practicable direct mitigation measures (including movable barriers, enclosures, quieter alternative methods, re-scheduling and restricting hours of operation of noisy tasks) to minimize the impact. If the mitigated noise levels still exceed the relevant criteria, the duration of the noise exceedance shall be given.
(e) The Applicant shall, as far as practicable, formulate a reasonable construction programme so that no work will be required in restricted hours as defined under the Noise Control Ordinance (NCO). In case the Applicant needs to evaluate whether construction works in restricted hours as defined under the NCO are feasible or not in the context of programming construction works, reference should be made to relevant technical memoranda issued under the NCO. Regardless of the results of construction noise impact assessment for restricted hours, the Noise Control Authority will process Construction Noise Permit (CNP) application, if necessary, based on the NCO, the relevant technical memoranda issued under the NCO, and the contemporary conditions/situations. This aspect should be explicitly stated in the noise chapter and the conclusions and recommendations chapter in EIA report.
(vi) Operational Noise Assessment
(a) Fixed Noise Sources
If the Project will cause impacts from any fixed noise sources, such as the ventilation systems of plants, the following assessment shall be followed.
(a1) Assessment of Fixed Source Noise Levels
The Applicant shall calculate the expected noise using standard acoustics principles. Calculations for the expected noise shall be based on assumed plant inventories and utilization schedule for the worst-case scenario. The Applicant shall calculate noise levels taking into account correction of tonality, impulsiveness and intermittency in accordance with Technical Memorandum for the Assessment of Noise from Places other than Domestic Premises, Public Places or Construction Sites issued under the NCO.
(a2) Presentation of Noise Levels
The Applicant shall present the existing and future noise levels in Leq (30 min) at the NSRs at various representative floor levels (in m P.D.) on tables and plans of suitable scale. A quantitative assessment at the NSRs for the proposed fixed noise source(s) shall be carried out and compared against the criteria set out in Table 1A of Annex 5 of the TM.
(a3) Proposals for Noise Mitigation Measures
The Applicant shall propose direct technical remedies within the Project limits in situations where the predicted noise level exceeds the criteria set out in Table 1A of Annex 5 of the TM to protect the affected NSRs.
(vii) Assessment of Side Effects and Constraints
The Applicant shall identify, assess and propose means to minimize any side effects and to resolve any potential constraints due to the inclusion of any recommended direct technical remedies.
(viii) Evaluation of Constraints on Planned Noise Sensitive Developments/Land uses
For planned noise sensitive uses which will still be affected even with practicable direct technical remedies in place, the Applicant shall propose, evaluate and confirm the practicability of additional measures within the planned noise sensitive uses and shall make recommendations on how these noise sensitive uses will be designed for the information of relevant parties. The Applicant shall take into account agreed environmental requirements / constraints identified by the EIA study to assess the development potential of concerned sites which shall be made known to the relevant parties.
3.4.3 Water Quality Impact
3.4.3.1The Applicant shall follow the criteria and guidelines for evaluating and assessing water pollution as stated in Annexes 6 and 14 of the TM respectively.
3.4.3.2 The Study Area for the purpose of water quality impact assessment shall cover the North Western, North Western Supplementary, Western Buffer, Deep Bay Water Control Zones as designated under the Water Pollution Control Ordinance (WPCO), Cap. 358. Sensitive receivers including nearby beaches between Lung Kwu Sheung Tan and East of Ma Wan such as Lung Kwu Upper & Lower Beaches, Butterfly Beach, Castle Peak Beach, Kadoorie Beach, Cafeteria New & Old Beaches, Golden Beach, Dragon Beach, Angler’s Beach, Gemini Beach, Ho Mei Wan Beach, Casam Beach, Lido Beach and Ting Kau Beach, as well as the Ma Wan Fish Culture Zone, Lung Kwu Chau & Sha Chau Marine Park; and the ecological sensitive receivers identified in Ecological Impact Assessment in 3.4.6 shall be addressed in the water quality assessment. In addition, the sea water intakes for Shiu Wing Steel Mill and the proposed EcoPark in Tuen Mun Area 38, Castle Peak Power Station and Black Point Power Station, Tuen Mun Area 38 Industries Intakes, Tuen Mun Flushing Water Intake, etc. shall also be addressed. This Study Area may be extended to cover other areas such as stream courses and the associated water system, existing and new drainage system, wetland, estuaries, coastal, marine and fresh water, groundwater system; and the associated catchment area(s) being impacted and to be identified during the course of the EIA study.
3.4.3.3 The Applicant shall identify and analyse physical, chemical and biological disruptions of marine, estuarine, fresh water, ground water system(s) and the associated catchment area(s), stormwater drainage system and coastal water arising during the construction and operation of the Project.
3.4.3.4 The water quality impact assessment shall cover the following, but not limited to, major areas of concern:
i) Construction and operational impacts arising from the additional berthing facilities;
ii) Dredging of marine sediment for the construction and maintenance of berthing facilities;
iii) Impacts of demolition and relocation of existing facilities; and making reference to the findings of the Land Contamination Assessment in 3.4.5; and
iv) Impacts of wastewater and effluent treatment and disposal during operational stage of the Project, such as the selective catalytic reduction and flue gas desulphurization processes.
3.4.3.5 Essentially the assessment shall address the following:
i) Collection and review of background information on the existing and planned water system(s) and the respective catchment(s) and sensitive receivers which might be affected by the Project.
ii) Characterization of water and sediment quality of the water system(s) and respective catchment and sensitive receivers which might be affected by the Project based on existing information or site surveys and tests as appropriate.
iii) Identification and analysis of existing and planned future activities and beneficial uses related to the water system(s) and identification of water sensitive receivers. The Applicant shall refer to, inter alia, those developments and uses earmarked on the relevant Outline Zoning Plans, Development Permission Area Plans, Outline Development Plans and Layout Plans;
iv) Establishment of pertinent water and sediment quality objectives, criteria and standards for the water system(s) and sensitive receivers in 3.4.3.5 (i), (ii) and (iii) above;
v) Identification of any alteration of water courses, natural streams, shoreline or bathometry, flow regimes, ground water levels, catchment types or areas;
vi) Review the specific construction methods and configurations of the Project, such as, but are not limited to, the dredging requirements; design and configuration of the berthing facilities;
vii) Review of the Project to identify any alteration of existing water course, natural streams/ ponds, shoreline or bathymetry, flow regimes, ground water level and catchment type or area;
viii) Identification, analysis and quantification of existing and likely future water and sediment pollution sources and loading, including point discharges and non-point sources to surface water runoff, spent industrial wastewater from the Project. Field investigation and laboratory tests shall be conducted as appropriate. Establishment and provision of an emission inventory on the quantities and characteristics of these pollution sources.
Wastewater and Non-point Sources Pollution
ix) Assessment and quantification on the adequacy of existing and future sewerage infrastructure to treat and dispose of the wastewater identified above. In general waste water generated shall have to meet the effluent discharge standards set out in the Technical Memorandum stipulated under the WPCO prior to discharge.
x) Assessment and quantification of existing and future water pollutants from non-point sources and analysis on the provision and adequacy of existing and future facilities to reduce such pollution.
Dredging, Filling and Dumping
xi) Identification and quantification of dredging, fill extraction, backfilling, mud/sediment transportation and disposal activities and requirements. Potential fill source and dumping ground to be involved shall also be identified. Field investigation, sampling and laboratory tests to characterize the sediment/mud concerned shall be conducted as appropriate. The potential for the release of contaminants during dredging shall be addressed using the chemical testing results derived from sediment and marine water samples collected on site and relevant historic data. Appropriate laboratory tests such as elutriate tests in accordance with the United States Army Corps of Engineers (USACE) method and sediment pore water (interstitial water) analyses shall be performed on the sediment samples to simulate and quantify the degree of mobilization of various contaminants such as metals, ammonia, nutrients, oxygen demand, trace organic contaminants (including Polychlorinated Biphenyls (PCBs), Polycyclic Aromatic Hydrocarbons (PAHs), Tributyltin (TBT) and chlorinated pesticides) into the water column during dredging. The ranges of parameters to be analyzed; the number, location, depth of sediment, type and methods of sampling; sample preservation; and chemical laboratory test methods to be used shall be subject to the approval of the Director. The Applicant shall also address the pattern of the sediment deposition and the potential increase in turbidity and suspended solid levels in the water column and at the sensitive receivers due to the disturbance of sediments during dredging, backfilling and dumping.
xii) In case of small scale dredging works and with the prior approval by the Director, the Applicant shall assess the potential increase in turbidity and suspended solids levels in the water column due to disturbance of marine sediments during dredging. The potential for release of contaminants during dredging shall also be addressed using the chemical testing results derived from sediment samples collected and tested in xi) above and relevant historic data;
Impact Prediction
xiii) Prediction and quantification, by mathematical modelling or other technique approved by the Director, of the impacts on the water system(s) and the sensitive receivers due to the construction and operation of the Project. The mathematical modeling requirements are set out in Appendix C of this Study Brief. Possible impacts include change in hydrology, flow regime, sediment erosion or deposition, water and sediment quality and the effects on the aquatic organism due to such changes in the affected water bodies. The prediction shall take into account and include possible different construction stages or sequences, and different operation stages.
xiv) Assessment of the cumulative impacts due to other related concurrent and planned projects, activities or pollution sources within a boundary around the Study Area to be agreed by the Director, that may have a bearing on the environmental acceptability of the Project through mathematical modelling. This shall include the potential cumulative construction and operational water quality impacts arising from, inter alia, the associated works of the Project, the activities and planned projects to be approved by the Director when the programme of the Project and associated works is confirmed during the course of the EIA study.
Mitigation
xv) Recommendation of appropriate mitigation measures to avoid or minimize the impacts identified above, in particular suitable mud dredging and disposal, and backfilling method(s). The residual impacts on the water system(s) and the sensitive receivers with regard to the relevant water and sediment quality objective, criteria, standards or guidelines shall be assessed and quantified by mathematical modeling as set out in Appendix C in this Study Brief or other techniques to be approved by the Director.
xvi) Identification and evaluation of the best practicable dredging, backfilling, marine mud disposal and reclamation methods to minimize marine mud disturbance and dumping requirements and demand for fill sources based on the criterion that existing marine mud shall be left in place and not be disturbed as far as possible.
xvii) Proposal of effective infrastructure upgrading or provision, water pollution prevention and mitigation measures to be implemented during the construction and operational stages so as to avoid and reduce the water and sediment quality impacts to within acceptable levels of standards. Requirements to be incorporated in the Project contract document shall also be proposed.
xviii) Best management practices to reduce storm water and non-point source pollution shall be investigated and proposed as appropriate. Attention shall be given to the water quality control and mitigation measures recommended in the “Practice Note for Authorized Persons and Registered Structural Engineers on Construction Site Drainage”.
3.4.3.1 Evaluation and quantification of residual impacts on the water system(s) and the sensitive receivers with regard to the appropriate water and sediment quality objectives, criteria, standards or guidelines using appropriate mathematical models as set out in Appendix C in this Study Brief or other techniques to be approved by the Director.
3.4.4 Waste Management Implications
3.4.4.1 The Applicant shall follow the criteria and guidelines for evaluating and assessing waste management implications as stated in Annexes 7 and 15 of the TM respectively.
3.4.4.2 The assessment of waste management implications shall cover the following:
(i) Analysis of Activities and Waste Generation
The Applicant shall identify the quantity, quality and timing of the waste arising as a result of the construction and operation activities of the Project, based on the sequence and duration of these activities.
(ii) Proposal for Waste Management
(a) Prior to considering the disposal options for various types of wastes, opportunities for reducing waste generation, on-site or off-site re-use and recycling shall be evaluated. Measures which can be taken in the planning and design stages e.g. by modifying the design approach and in the construction stage for maximizing waste reduction shall be separately considered.
(b) After considering the opportunities for reducing waste generation and maximizing re-use, the types and quantities of the wastes required to be disposed of as a consequence shall be estimated and the disposal options for each type of waste shall be described in detail. The management of the by-products to be generated from the FGD Process shall be addressed in details. The disposal method recommended for each type of waste shall take into account of the result of the assessment in (c) below.
(c) The impact caused by handling (including labelling, packaging & storage), collection, and disposal of wastes shall be addressed in detail and appropriate mitigation measures shall be proposed. This assessment shall cover the following areas :
&nb