17 Conclusion and recommendations

17.1 Introduction

17.1.1 This EIA Report has provided an assessment of the potential environmental impacts associated with the construction and operational phases of the proposed developments under the Project, “Further Development of Tseung Kwan O - Feasibility Study”.

17.1.2 Specific mitigation measures requirements for the Project, as well as an environmental monitoring and auditing programme, have been developed during the assessment of the proposed developments. The Implementation Schedule of the recommendations is presented in Section 18. The principal findings of this study are summarized below.

17.2 Air Quality Impact

Construction Phase

17.2.1 Air quality impacts from the construction works for the Project would mainly be related to construction dust from excavation, materials handling, filling activities and wind erosion. With the implementation of mitigation measures specified in the Air Pollution Control (Construction Dust) Regulation and EM&A programme, dust impact on air sensitive receivers would be minimal.

Operation Phase

17.2.2 For the operation phase, cumulative air quality impact arising from vehicular emissions from roads, portal emissions from the WCR, Eastern Harbour Crossing, Lei Yue Mun Road underpass, deck-over of Sceneway Garden, tunnel section of link roads of WCR/ CBL Road P2 interchange and the Road P2 decked road sections, emissions from idling traffic near the WCR and EHC toll plazas, emissions from the EHC vent shafts and WCR ventilation exhaust buildings, emissions from the industry chimneys at Yau Tong and emissions from the landfill gas flaring plant located at Sai Tso Wan Landfill and TKO Stage I & Stage II/III Landfills is anticipated. Air quality modelling was carried out to assess their impacts in view of installation of proposed noise barriers/ enclosures on WCR, CBL and Road D4 flyover. With the proposed ventilation systems (relocation of the Mid-Ventilation Building and extraction of 7090% tunnel emission from the WCR eastboundwestbound tunnel through vent shaft facing southerlyupward direction at the Eastern Portal Ventilation Building at TKO area, and extraction of 70% tunnel emission from WCR eastbound tunnel through vent shafts facing upward direction at Eastern Portal Ventilation Building at TKO area) ), the predicted air quality impacts at all representative ASRs would satisfy the AQO.

17.2.3 The air pollutant concentration in the WCR tunnel would meet the EPD guideline provided the tunnel is provided with an effective ventilation system. With the installation of high efficiency deodourization units, insignificant odour impacts are expected from sewage pumping station at the southern end of TKO Stage 1 Landfill near Area 86,.

17.3 Noise Impact

Construction Phase

17.3.1 This assessment has predicted the construction noise impacts associated with the construction works of the proposed Project. With the use of silenced equipment, and the use of movable noise barriers for some plant, all representative NSRs would comply with the construction noise criteria.

Operational Phase

17.3.2 The potential road traffic noise impacts were assessed for the worst-case traffic flows in the years 2016 and 2031. Without mitigation, most of the noise sensitive receivers were predicted to exceed the EIAO-TM traffic noise criteria. Direct mitigation measures such as use of low-noise road surfacing materials, roadside barriers and enclosures, are proposed on the ‘new’ roads to alleviate the traffic noise impacts. In addition, it is also recommended wherever possible to reduce traffic noise impacts in planned areas through careful building layout/ designs. With the implementation of all the recommended mitigation measures, no exceedance of the relevant noise limit was predicted at the representative NSRs due to noise from ‘new roads’, except is still predicted at some planned educational institutions some NSRs due to noise from ‘new’located at Areas 86, 65C, 67 and 74S roads. Once all the available direct mitigation measures have been exhausted, these affected educational NSRs should be provided with indirect technical remedies in the forms of air-conditioning and appropriately glazed windows. It should be noted that the schools proposed in Areas 86, 67 and 74S are standard school and the indirect technical remedies for these schools are standard measures in line with the Class Assessment Document for Standard Schools. Once all the available direct mitigation measures have been exhausted, the affected NSRs would be provided with indirect technical remedies such as air-conditioning and appropriately glazed windows.

17.3.3 The predicted noise levels at the NSRs in the vicinity of the proposed WCR Mid-Vventilation bBuildings and pumping stations would comply with the EIAO-TM criterion. The closest NSRs in vicinity of proposed WCR Eastern Portal Ventilation Building would also meet the EIAO-TM standard, provided that if the acoustic silencers are installed for reversible fans. sound emission levels of the noise sources are designed to meet with the recommended noise levels.

17.3.4 Monitoring of noise is considered necessary to verify the effectiveness of the mitigation scheme. It is recommended that traffic noise monitoring should be carried out at the representative NSRs for the section of CBL near Area 86, Road D4 Flyover and the section of WCR in Kowloon area, during the first year after road opening. Noise monitoring should also be carried out during the commissioning stage of the Eastern Portal vVentilation bBuildings and pumping stations. The recommended mitigation measures, monitoring procedures and locations are presented in the stand-alone EM&A Manual.

17.4 Water Quality Impact

Operational Phase

17.4.1 Water quality modelling results indicated that the proposed WCR reclamation and construction of the CBL bridge would not cause any adverse impact on the marine water quality in Junk Bay and Victoria Harbour, taking into account the cumulative effect of all possible pollution sources including those from landfill sites, non-point source surface run-off and sewage from cross connectionsOperational water quality modelling results indicated that the proposed WCR reclamation and construction of CBL bridge would not cause any adverse impact on the marine water quality in Junk Bay and Victoria Harbour, taking into account the cumulative effect of all possible pollution sources including those from landfill sites, non-point source surface run-off and sewage from cross connections.

17.4.2 To minimise cope with the potential impacts on the proposed beneficial use of Eastern Drainage Channel (EDC) for recreation activities, drainage diversion work is proposed under this Project to divert two existing storm outfalls from in the EDC to the south of TKO town centre to enhance the dispersion of pollutants. Modelling results indicated that EDC and Junk Bay water quality would generally be acceptable for secondary contact recreation with the recommended drainage diversion. Monitoring of water quality is recommended to verify the model predictionTo cope with the potential impact on the proposed beneficial use of Eastern Drainage Channel (EDC) for secondary contact recreation, drainage diversion work is proposed under this Project to divert two existing storm outfalls in EDC to the south of TKO town centre to enhance the dispersion of pollutants. Modelling results indicated that EDC and Junk Bay water quality would generally be acceptable for secondary contact recreation under the ultimate condition with further development of TKO in 2016.

17.4.3 Water recreation activity quality impact on the proposed beneficial use in the area of the EDC and Junk Bay could be affected by due to the emergency release of sewage bypass at the either the seawall or the submarine outfall, but impacts are is expected to be short-term. The occurrence of such an event is considered to be very In the remote. Nevertheless, should it case that it occurs, the plant operators of Tsueng Kwan O Preliminary Treatment Works (TKOPTW) should closely communicate with EPD and LCSD to ensure appropriate actions can be undertaken to close the EDC and Junk Bay for water recreation activities. Water quality monitoring is recommended at such a time to determine when conditions are suitable for re-opening of the EDC and Junk Bay for recreational purposes. No insurmountable water quality impact on the proposed beneficial use is expected from any these temporary discharges under emergency situationThe water quality impact on the proposed beneficial use of EDC and Junk Bay due to the emergency bypass at seawall or submarine outfall is expected to be short-term. In the remote case that it occurs, the plant operators of TKO PTW should closely communicate with EPD and LCSD to ensure appropriate actions are undertaken to close the EDC and Junk Bay for water recreation activities. No insurmountable water quality impact on the proposed beneficial use is expected from these temporary discharges under emergency situation.

Construction Phase

17.4.4 Short-term water quality impact could be associated with the proposed construction works. Impacts may result from the surface runoff from construction sites, sewage from on-site construction workers, wastewater from general construction activities, dredging and filling operations and Deep Cement Mixing (DCM) treatment[1]. Impacts could be controlled to comply with relevant standards in the Water Pollution Control Ordinance (WPCO) standards by implementing the recommended mitigation measures. Therefore, Uunacceptable residual impacts on water quality are not expected. Monitoring of water quality is recommended to verify the effectiveness of the mitigation measuresShort-term water quality impact would be associated with the proposed construction works. Impacts may result from the surface runoff, sewage from on-site construction workers, wastewater from general construction activities, dredging and filling operations and Deep Cement Mixing (DCM) treatment. Impacts could be controlled to comply with the Water Pollution Control Ordinance (WPCO) standards by implementing the recommended mitigation measures. Unacceptable residual impacts on water quality are not expected.

17.5 Sewerage and Sewage Treatment Implications

17.5.1 The performance of the existing and committed sewerage infrastructure under full development condition for the ultimate scenario was assessed and formed the Baseline Condition. The development projections for 2016 studied is reflective of the approved OZP condition. The SIA Condition takes into account of the recommended development proposal for TKO sewerage catchment which involves TCS, TKL and PSK.

17.5.2 The adopted unit flow factors are generally based on the recommendations of the Sewerage Manual Part 1 and are in line with the Environmental and Engineering Feasibility Assessment Studies in Relation to the Way Forward of the Harbour Area Treatment Scheme (EEFS). The total flows generated by the TKO sewerage catchment are estimated to be 165,515m³/d and 161,510m³/d for Baseline and SIA Conditions respectively.

17.5.3 The recommended peaking factors are based on the Sewerage Manual. The estimated peak flow is 4.58m³/s for Baseline Condition whilst peak flow of 4.47m³/s is estimated under SIA Condition. These peak flows are used in the hydraulic assessment of the existing and committed sewerage systems, TKO PTW and the HATS Stage I Tunnel section from TKO to Kwun Tong.

17.5.4 The performance assessment results have identified surcharged sewers measuring a total length of 690m with diameters ranging from 450mm to 1,050mm under the SIA peak flow condition. Under 1.15 times of the SIA peak flow condition, the total length of surcharged sewers is 1,780m with a similar range of pipe sizes. The analyses indicated that there are no risks of overflow under the various flow conditions as the available freeboards exceed 1m. Works to improve these surcharged sewers are not accorded as top priority in accordance with the Sewerage Manual. In addition, some 302m of sewers were identified with adverse gradients.

17.5.5 Whilst there is an overall reduction in population and flows as a consequence of the reduction of development density in further development in TCS, TKL and PSK within TKO catchment, it is noted that there are local increases of population and flows in Planning Area 66, 68 and 78. The performance assessment results showed that these local effects did not cause any additional adverse impacts on the sewerage system.

17.5.6 The TKO PTW was assessed to be adequate to convey the total ultimate catchment flows under both Baseline and SIA Conditions under this Study. In accordance with the EEFS, the HATS Stage I Tunnel section from TKO to Kwun Tong was also assessed to be adequate to handle the projected flows under both Baseline and SIA Conditions.

17.1.1 According to the sewerage records and the proposed works in TKO catchment, there were no existing or planned sewerage systems to serve the developments at Planning Area 65, 65B, 66, 67, 68, 72 and Pak Shing Kok. New sewers of 300mm and 600mm diameter with total lengths of approximately 1,203m and 1,081m are proposed to connect these areas to the existing sewerage system. The cost for the proposed new sewers is about $12M.

17.5.7

17.5.8 SewerageSewerage improvement works to the existing and committed sewerage infrastructure were recommended when opportunity arises, e.g. in conjunction with road works and/or nearby sewerage projects, in future. It is proposed to upgrade the existing sewers with pipes of diameters ranging from 450mm to 1,050mm in order to relieve the identified hydraulic inadequacies and surcharged condition.

17.6 Terrestrial Ecology

17.6.1 A literature review and 6-month ecological surveys covering the wet season were undertaken to establish the ecological profile of the Assessment Area. As much of the proposed development area is dominated by highly disturbed urban districts, terrestrial ecological impact assessment was focussed on three areas where direct/indirect impacts to terrestrial ecological sensitive receivers are anticipated.

17.6.2 The Assessment Areas were found to be dominated largely by relatively low ecological value habitats, including areas of wasteland and developed areas. Habitats considered of conservation interest included moderate-high ecological value secondary woodland in the PSK Assessment Area, and moderate ecological value stream habitats in the E-WCR and PSK Assessment Areas.

17.6.3 Four plant species of conservation interest were recorded from the Assessment Areas during recent surveys. Although the recorded species are all relatively common in Hong Kong, they are either protected through Hong Kong or mainland Chinese Legislation, or are considered to have regionally or globally threatened populations.

17.6.4 Several faunal species of conservation interest were recorded in the Assessment Areas, comprising one fish, two reptile, two mammal, one freshwater invertebrate, and 13 bird species. Of particular interest was the fish species Philippine Neon Goby (Stiphodon artopurpureus), recorded from a small stream below the TKO Permanent Chinese Cemetery. Previous records of the Eurasian Eagle Owl (Bubo bubo), which is of regional conservation interest, have also been made from the E-WCR Assessment Area. Although not recorded during recent surveys, it is possible this species still occurs in the Assessment Area.

17.6.5 Direct terrestrial ecological impacts resulting from developments proposed under this Project would generally be confined to small areas of relatively low ecological value habitats. No direct impacts to moderate-high ecological value secondary woodland or moderate ecological value streams are expected. Habitat loss resulting from the proposed works is expected to result in minor and acceptable ecological impacts.

17.6.6 Individuals of two of the plant species of conservation interest would be directly impacted by works proposed under this Project. It is recommended that the plants be transplanted to suitable nearby habitats outside of the proposed works areas prior to the construction phase.

17.6.7 Impacts to the majority of faunal species of conservation interest recorded in the Assessment Areas are expected to be relatively minor in scale. Many of the recorded species are often found in urban/developed areas, and are not considered particularly sensitive to disturbance (e.g., Black Kite, Milvus lineatus). Other species (e.g., Besra, Accipiter trivirgatus) were recorded at some distance from the proposed works areas, and therefore would not be affected by construction or operation phase activities. Records of some species (e.g., Black-naped Oriole, Oriolus chinensis) refer to occasional sightings of migrant birds that would not be substantially affected by the proposed works.

17.1.1 Without

17.6.8Without mitigation, substantial impacts to the Philippine Neon Goby population recorded from the E-WCR Stream have been predicted. Although no direct impacts to the stream habitat are expected, reclamation works for the WCR within Junk Bay would result in the loss/disturbance of habitats potentially utilised by juvenile Neon Gobies. Measures to protect adult fishes during the construction phase and to provide suitable passage from the stream to marine habitats during the operation phase have therefore been recommended.

17.6.9 Measures to avoid, minimise and compensate for various identified ecological impacts have been recommended. With the implementation of the recommended mitigation measures, residual terrestrial ecological impacts resulting from developments proposed under this Project are expected to be ecologically acceptable.

17.7 Marine Ecology

17.7.1 Literature review of existing marine ecological conditions was supplemented by field surveys of marine ecological resources in the Assessment Area. Surveys were conducted over a 6 month period from May to October 2004. Marine habitats affected by WCR reclamation and construction of CBL were generally of low ecological value. Rocky and sandy shore habitats were considered to be of low-medium ecological value. Artificial seawall and marine mammal habitat was rated as being of very low ecological value. Soft substrata subtidal habitat at Junk Bay was considered to be of low ecological value. Owing to the sparse cover of common hard corals and patchy cover of soft and gorgonian corals, the ChuiChiu Keng Wan coast at the proposed reclamation area was considered to be of low ecological value.

17.7.2 WCR reclamation would cause direct and permanent loss of 1km of natural rocky shore and 0.2km of sandy shore. A total of 16.5ha of subtidal habitat would be permanently lost mainly due to the WCR reclamation area (16.3ha) but also due to construction of piers for the CBL (0.2ha). Impacts to marine habitats (and natural shorelines in particular) have been avoided and minimised as far as practicable taking into account engineering constraints and also constraints posed by other environmental considerations (e.g., the visual impact of the WCR reclamation). Direct impacts to these habitats therefore would be largely mitigated for through the compensation provided by construction of a sloping rubble mound seawall: the seawall would provide a suitable habitat for rocky inter-tidal and coral community re-colonisation. WCR reclamation would cause direct and permanent loss of 1km of natural rocky shore and 0.2km of sandy shore. A total of 16.5ha of subtidal habitat would be permanently lost mainly due to the WCR reclamation area (16.3ha) but also due to construction of piers for the CBL (0.2ha). Owing to construction methods, dredging would be relatively small scale and be conducted for approximately 1 month. With the implementation of recommended water quality mitigation measures, indirect impacts on adjacent hard substrata subtidal habitat, which supported sparse hard coral, and some soft and gorgonian corals, were predicted to be low.

17.7.3 In summary, residual marine ecological impacts resulting from the Project were assessed as being minor and acceptable.

17.8 Fisheries Impact

17.8.1 A literature review has been conducted to incorporate the latest relevant information for determining impacts on fisheries arising from the Project.

17.8.2 The size of catches in the Junk Bay assessment area were ranked as low – moderate compared to other fishing grounds in Hong Kong though the fish species captured were considered to be of low commercial value. Fishing grounds in inner Junk Bay were considered to be of low commercial importance. The only sensitive fisheries receiver identified in the vicinity of the project was the Fish Culture Zone at Tung Lung Chau.

17.1.1The proposed WCR reclamation and CBL construction would result in the direct loss of approximately 16.5 ha of fishing ground at inner Junk Bay. The loss of this area is anticipated to have a relatively low effect on fisheries production of Hong Kong as a whole.

17.8.3 P
Provided that recommendations to protect water quality (Section 5) are fully implemented, specific mitigation measures to protect fisheries resources would not be necessary. Similarly, audit activities on work sites to ensure prevention of water quality impact would also serve to protect fisheries resources. Therefore EM&A programme for fisheries is not necessary.

17.9 Landscape and Visual Impact

17.9.1 The potentially most significant impacts during the construction phase will be the permanent and irreversible loss of the Landscape Resources of Natural Coastline and Topography along the Western side of Junk Bay (LR5) and Inner Junk Bay (LR60). It is estimated that approximately 1km of natural coastline and 10.52.3 ha of Junk Bay will be permanently lost by the reclamation works associated with DP1 - Western Coast Road. The Landscape Character Area of Inner Junk Bay (LCA9) will also be permanently impacted upon. The residual landscape impact for these resources and character areas will be substantial.

17.9.2 The Landscape Character Areas of Tseung Kwan O Southern Reclamation (LCA1) and Pak Shing Kok Cement Works (LCA7) will be impacted by the construction of new buildings and roads. The residual landscape impact for these character areas will be moderate.

17.9.3 The Landscape Resources of Coastal Woodland on the slopes along the western side of Junk Bay (LR6), Woodland Vegetation above Chui Ling Road (LR15) Woodland Vegetation on the northern side of Lei Yue Mun Road (LR64), the open space(LR66) and vegetation (LR67) at the intersection of Lei Yue Mun Road and Kai Tin Road, the Natural Hillside and Quarry Face to the west of the Harbour Tunnel Road (LR74) and the Landscape Character Areas of Lam Tin To Lei Yue Mun Residential Area (LCA13), Sai Tso Wan Urban Fringe (LCA14) and Cha Kwo Ling Cargo Area (LCA15) will be impacted by the tunnel portals, ventilation buildings, slope stabilisation works and vegetation clearance during the construction of the Western Coast Road. The residual landscape impact for these resources and character areas will be moderate.

17.9.4 The potentially most significant visual impacts during the construction phase will be for the VSRs at the Residential Development at Oscar by the Sea (R1), Choi Ming Court (R4), Bauhinia Gardens (R5), Beverey Gardens (R6), Ocean Shores (R10), Commercial / Residential Development Developments of Area 86 (C/R1), Tseung Kwan O Plaza (C/R3), Park Central (C/R4), the Recreational Users at Area 77 (O1) and Area 47 (O5) on the Tseung Kwan O side of Devil's Peak. These VSRs will have open views of the new buildings associated with the further development of TKO, the reclamation associated with WCR, CBL, Road P2 and night time lighting. These VSRs will have substantial residual visual impacts during the construction phase due to their open views of the bay and proximity to the works.

17.9.5 On the Lam Tin side of Devil's Peak, the VSRs of the existing high-rise development at Eastern Harbour Crossing Residential (R12), the Commercial / Residential Development along Cha Kwo Ling Road (C/R8), the Planned Residential Development R(A)4 at Kaolin Mine Site (R21) and the village houses located along Cha Kwo Ling Road (R14) will have views of the western tunnel portal, vegetation clearance, noise barriers, elevated road structures along the waterfront and slope stabilisation works. These VSRs will have substantial residual visual impacts during the construction phase due to their open views of works.

17.9.6 During the construction phase all other VSRs on both the Tseung Kwan O side and the Lam Tin side of Devil’s Peak will suffer moderate, slight or negligible residual visual impacts.

17.9.7 The potentially most significant landscape impacts during the operation phase will be the permanent and irreversible loss of the Landscape Resources of Natural Coastline and Topography along the Western side of Junk Bay (LR5) and Inner Junk Bay (LR60). It is estimated that approximately 1km of natural coastline and 10.5 ha of Junk Bay will be permanently lost by the reclamation works associated with the Western Coast Road. The Landscape Character Area of Inner Junk Bay (LCA9) will also be permanently impacted upon. These Landscape Resources and Character Area will have a substantial residual landscape impact.

17.9.8 For the Cross Bay Link, the design of the bridge as a feature will result in a slight positive impact for the Landscape Character Area of Junk Bay (LCA9A).

17.9.9 On the Lam Tin side of Devil's Peak, the VSRs of the existing high-rise development at Eastern Harbour Crossing Residential (R12) will have close range views of the western tunnel portal, noise barriers, elevated road structures and slope stabilisation works. This VSR will have moderate residual visual impacts during the operation phase due to their close range, open views of works.

17.9.10 During the operation phase, after implementation of the proposed mitigation measures, all other VSRs on both the Tseung Kwan O side and the Lam Tin side of Devil’s Peak will suffer either slight or negligible residual visual impacts.

17.9.11 Overall, it is considered that, in terms of Annex 10 of the EIAO TM, the landscape and visual impacts are acceptable with mitigation measures. While the residual impact on the Landscape Resources (Natural Coastline and Topography along the Western side of Junk Bay (LR5) and Inner Junk Bay (LR60) and Character Area Inner Junk Bay (LCA9)) will remain substantial, the current proposal impacts substantially less the natural coastline than the original coastal alignment, and ensures that areas of coral further along the coast are not disturbed. The tunnel proposal has minimised the amount of reclamation as far as practicable.

17.10 Waste Management Implications

17.10.1 The dredged volume for the WCR Phase 1 Reclamation was estimated to be approximately 20,000 m³. With the implementation of the recommended mitigation measures and management procedures in accordance with the requirements of ETWB TCW No. 34/2002, no residual impact was predicted.

17.10.2 Other waste types generated by the construction activities are likely to include C&D material (from foundation, excavation and tunnelling works), general refuse from the workforce and chemical wastes from the maintenance of construction plant and equipment. Provided that these identified waste arisings are to be handled, transported and disposed of using approved methods and that the recommended good site practices are to be strictly followed, adverse environmental impacts would not be expected. During the operation phase, domestic waste would be generated by the planned residential use at the new development areas at PSK, TCS and TKL. Domestic waste generated in the development areas would be directed to the SENT Landfill.

17.11 Biogas Assessment

17.11.1 The calculations show that, assuming 75% biodegradable TOC (which is a worst-case scenario) the estimated methane emission from the WCR reclamation is estimated to be well below all relevant assessment criteria. It is therefore concluded that the methane gas generation potential is not expected to pose a development constraint to the proposed WCR reclamation.

17.11.2 Furthermore, the planned land use of highway and toll plaza on the proposed WCR reclamation is not sensitive to potential biogas emission. The proposed administration building of the toll plaza would not have a basement and therefore potential biogas emissions would be considered to pose a very limited, if any, risk.

17.12 Impact on Cultural Heritage

17.12.1 Based on the baseline review and the marine geophysical survey results, a surface anomaly having archaeological potential was identified. This surface anomaly is located close to one of the proposed piers of the CBL and could be directly impacted. A visual diver survey should be carried out during the detailed design stage of the Project. The dive survey should cover the surface anomaly and those shallow water areas to be reclaimed that were not covered by the marine geophysical survey.

17.12.2 No pre-war clan or notable feng shui features such as feng shui woods and ponds or historical trackway or other historic features were identified within the study area. Fourteen notable buildings and structures were identified. Since all of the identified notable buildings and structures are located outside the project boundary, direct impacts are not expected. Nevertheless, since Cha Kwo Ling Tin Hau Temple is located less than 50m from the works area of the proposed roundabout at Cha Kwo Ling, it may be indirectly impacted by dust and vibration due to the nearby construction activities of the Project. To prevent damage to Cha Kwo Ling Tin Hau temple during the construction phase, a temporarily fenced-off buffer zone (with allowance for public access) should be provided around the temple. Monitoring should be carried out at the temple during the construction period.

17.13 Landfill Gas Hazard Assessment

17.13.1 The results of the qualitative risk assessment of landfill gas hazard to the proposed project posed by TKO Stage I & II/III Landfill and Sai Tso Wan Landfill suggested that the overall level of the landfill gas hazard would be “medium” for the three areas.

17.13.2 Some appropriate protection measures have been proposed to minimise the landfill gas hazard at the proposed project site during the construction phase and operational phase. These measures should be implemented during the construction phase and/or operational phase of the proposed project, as necessary.

17.13.3 Provided that the recommended protection measures are implemented properly, the health and safety of the site workers/personnel working at the proposed project site would be safeguarded and there would be no adverse impact on the feasibility of the proposed project.

17.14 Hazard to Life

17.14.1 With reference to the EIA Study Brief, the hazard to life of the proposed Dangerous Goods Vehicles Ferry Pier (DGVFP) that could result from modification of the access road to the vehicle queuing area (due to the two WCRTrunk Road T2 slip roads proposed under this study) was assessed.

17.14.2 In the assessment, three changes introduced by the two proposed slip roads to the surrounding environment of the proposed DGVFP were noted but the changes would not induce significant change to the risk levels associated with the proposed DGVFP. Therefore, it is considered that the hazard to life associated with the proposed DGVFP with the modifications of the access road to the vehicle queuing area would be acceptable.

17.15 Overall Conclusion

17.15.1 The findings of this EIA have provided information on the nature and extent of environmental impacts arising from the construction and operation of the Project. The EIA has, where appropriate, identified mitigation measures to ensure compliance with environmental legislation and standards.

17.15.2 Overall, the EIA Report has predicted that the Project would be environmentally acceptable with the implementation of the proposed mitigation measures for construction and operation phases. An environmental monitoring and audit programme has been recommended to ensure the effectiveness of recommended mitigation measures.

17.1.1The findings of this EIA have provided information on the nature and extent of environmental impacts arising from the construction and operation of the Project. The EIA has, where appropriate, identified mitigation measures to ensure compliance with environmental legislation and standards.

17.1.1Overall, the EIA Report has predicted that the Project would be environmentally acceptable with the implementation of the proposed mitigation measures for construction and operation phases. An environmental monitoring and audit programme has been recommended to ensure the effectiveness of recommended mitigation measures.

17.1.1The Project is to review the overall planning for the TKO further development to take account of the recent changes in planning parameters and to ensure a comprehensive planning approach to the development of this area within the context of the South East New Territories Development Strategy.

17.1.1The Project aims to formulate a comprehensive plan for the further development of TKO, covering TCS, PSK and the remaining area of TKL which will address all the issues arising from the development, and will integrate the new and existing/planned developments of the new town in a coherent manner.

17.1.1The aim is to improve the overall design of the new town with the vision to build TKO into a new town that can boast of its convenience, vibrancy, distinctive urban design and quality living environment.

17.1.1To support the further development of TKO, major highway infrastructure such as WCR and CBL are required. Optimum planning and engineering solutions for new development areas and major highway infrastructure elements must be found such that these together with the existing and planned developments in TKO, fit together in a coherent manner and provide for an optimum level of population and development.

Project Scope

17.1.1The scope of the Project comprises:

(i)local road and engineering infrastructure for TCS, PSK and remaining areas of TKL;

(i)local engineering infrastructure for the proposed recreational development at TKO Stage 1 Landfill;

(i)modification of existing infrastructure to serve TCS development;

(i)WCR to provide a linkage between TKO and the main urban area;

(i)CBL to provide a linkage between the eastern and south-eastern areas of TKO as an alternative route bypassing the New Town Centre; and

(i)Road P2 to provide an extension of Po Shun Road to connect with WCR.

Project Benefits

17.1.1The new planning has considered reduced residential density in TCS and the remaining area of TKL, use of TKO Stage I Landfill for leisure and recreation, extensive park developments and waterfront promenade providing a variety of open spaces and deletion of planned waterfront roads to create a traffic free pedestrian environment with easy access to bring people to the waterfront. The TCS development area provides opportunity to create a better living environment through good urban design planning with an attractive waterfront for the enjoyment of TKO residents. The Eastern Channel and Inner Junk Bay would be utilised for water recreation activities. More landscape open space in TKL will alleviate the impact of the surrounding high density environment.

17.1.1The proposed WCR will serve as a relief to the existing TKO Tunnel as well as the existing TKO roadnetwork. The proposed CBL will provide the necessary relief to the existing Wan Po Road which is the only existing route linking south-east TKO including Area 86 development, TKO Industrial Estate and Area 137 development with the TKO Town Centre. It also diverts the industrial traffic away from the Town Centre.

Consequences of Not Proceeding with the Project

17.1.1Without the necessary local infrastructure to serve TCS, TKL and PSK, these development areas cannot be developed as planned.

17.1.1Without WCR and CBL, the traffic congestion envisaged at the existing TKO Tunnel and Wan Po Road cannot be relieved. The development potential of the south-eastern of TKO is constrained without these road infrastructure.

17.1The proposed sewerage system would serve to collect and transfer the sewage arising from the existing villages including restaurants to the proposed STW and submarine outfall for proper treatment and disposal.  This would achieve the effect of eliminating untreated or partially treated sewage discharges to Picnic Bay.  This represents the major benefit of the Project, not only in the respect of water quality improvement to the Bay but also to the local environment in the residential areas by eliminating unhealthy, malodorous and potentially visually unpleasant surface discharges.

17.113.34. This EIA has identified potential environmental impacts of various nature including air quality, noise, water quality, sediment contamination, solid waste, ecology, fisheries and landscape and visual associated with the implementation of the Project.  The potential environmental impacts would be expected to arise during both construction and operational stages if no mitigation measures are in place.

17.1

17.113.35. With the recommended mitigation measures applied, the Project would be environmentally acceptable and no unacceptable residual impacts would be anticipated.  Table 13.1 summarises the environmental outcomes/benefits from the implementation of the Project and the recommended mitigation measures.  The schedule of implementation of the recommended mitigation measures has been provided in Chapter 12 – Implementation Schedule.  Monitoring requirements have also been specified in a separate EM&A Manual to ensure proper implementation of the recommended mitigation measures. 

17.1

17.1

Table 13.1       Summary of Key Environmental Outcomes/benefits

Issue	Mitigation Measures and Environmental Outcomes/Benefits
The Project	Provision of a new sewage collection, treatment and disposal facilities for Sok Kwu Wan area in order to: · Eliminate the direct discharges of untreated or partially treated sewagegenerated from approximately 1300 residents, 6000 day visitors and restaurants in Sok Kwu Wan area into coastal area of Picnic Bay in 2016 (which are equivalent to the ultimate population figures) as well as from Lo So Shing and Mo Tat Wan which would have total residents of approximately 532 in 2016. · Improve the water quality of Picnic Bay. · Improve the local environment in the residential areas by eliminating unhealthy, malodorous and potentially visually unpleasant surface discharges.
Option Selection & Design	The locations and design of the proposed sewer alignment, pumping stations, STW and submarine outfall are considered environmental friendly due to the following reasons: · Avoid or reduce impacts on sites of archaeological interest and cultural heritage importance (Lo So Shing Archaeological Site). · Avoid reclaiming land for STW construction. · Reduce the risk of untreated sewage leakage by selecting the route with shorter pipeline on land. · Minimizethe encroachment into private lot and the LCSD playground. · Minimize the loss/disturbance of vegetated areas. · Avoid direct impact on coral habitats with the use of HDD. · Minimize potential water quality impacts on nearby sensitive receivers by extending the outfall length, eliminating the need of reclamation, and using of no-dig method for inshore section of the outfall pipeline. · Improve water quality of Picnic Bay by eliminating the discharge of untreated or partially treated sewage and providing a full secondary treatment with nitrogen removal and UV disinfection unit. · Minimize the extent of construction dust and noise impacts (i.e. the selected route would avoid affecting the receivers in Lo So Shing)
Air Quality –Construction Phase	2m high solid fence around construction site of Pumping Station P2 and dust suppression measures stipulated in Air Pollution Control (Construction Dust) Regulation are proposed to protect the nearby ASRs. All ASRs would be protected to comply with AQQ and EIAO-TM standards.
Air Quality –Operation Phase	All pumping stations, sequence batching reactor (SBR) feed pump station and sludge dewatering room would be enclosed and installed with deodorisation facilities. All ASRs would comply with of EIAO-TM odour standard.
Noise – Construction phase	Use of quieter plants, limiting number of some powered mechanical equipment, use of noise screening structures and manual working method are proposed to protect the NSRs located near the pumping stations and along the sewer alignment. All NSRs comply with EIAO-TM noise standards, except short-term residual impact during sewer construction.
Noise – Operation phase	Installation of a silencer with at least 8 dB(A) noise reduction at Pumping Station P1a is recommended. All NSRs would be protected to meet both daytime and nighttime noise criteria.
Water Quality – Construction Phase	Use of HDD for the inshore section outfall pipeline installation, reduction of dredging rate and use of 2-layer silt curtains are recommended to protect the FCZ at Picnic Bay and secondary contact recreation subzone at Mo Tat Wan. The FCZ and secondary contact recreation subzone would be protected to be within the relevant WQO.
Water Quality – Operation Phase (Normal Operation)	Provision of full secondary treatment with nitrogen removal and UV disinfection and disposal of treated sewage at a long submarine outfall near the mouth of Picnic Bay. The FCZ and secondary contact recreation subzone would comply with WQO, except WQO limit for TIN due to the high background level which has already exceed the limit.  The predicted TIN levels would fall within the background variations of TIN levels at Picnic Bay.
Water Quality – Operation Phase (Emergency Discharge)	Mitigation measures such as provision of standby pump and standby generator, 24-hour temporary storage and contingency measures are recommended to minimize the occurrence of emergency discharge and potential water quality impact if an overflow does occur, in order to protect the FCZ at Picnic Bay. With the implementation of the recommended mitigation measures and contingencies, the occurrence of emergency discharge and the residual impacts in the unlikely event that an overflow does occur would be minimised.
Ecology	Use of HDD for the inshore section of outfall pipeline would avoid the loss of coral habitats and reduce the temporary seabed loss due to dredging. Fencing and labelling of uncommon tree species is proposed to avoid direct or indirect disturbance during construction.  No significant and unacceptable residual impact would be expected.
Fisheries	With the implementation of the mitigation measures recommended for the water quality impact, no unacceptable residual impact on fisheries would be expected.
Landscape and Visual Impact	Appropriate construction practice, design and surface treatment of the built elements and appropriate soft landscape treatment within available areas of the Project are recommended to mitigate the potential landscape and visual impacts. Landscape and visual impacts would be acceptable with the recommended mitigation measures.

17 Conclusion and recommendations. 17-1

17.1 Introduction.. 17-1

17.2 Air Quality Impact. 17-1

17.3 Noise Impact. 17-1

17.4 Water Quality Impact. 17-2

17.5 Sewerage and Sewage Treatment Implications. 17-3

17.6 Terrestrial Ecology.. 17-4

17.7 Marine Ecology.. 17-5

17.8 Fisheries Impact. 17-617-617-617-5

17.9 Landscape and Visual Impact. 17-6

17.10 Waste Management Implications. 17-7

17.11 Biogas Assessment. 17-917-917-917-8

17.12 Impact on Cultural Heritage. 17-917-917-917-8

17.13 Landfill Gas Hazard Assessment. 17-917-917-917-8

17.14 Hazard to Life. 17-917-917-917-8

17.15 Overall Conclusion.. 17-1017-1017-1017-9

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[1] DCM {Deep Cement Mixing} is a well-known sediment treatment method to improve the load-bearing strength of sediments so they could be left in-situ under, in this instance, the future seawall for the WCR reclamation.