13 Summary of Env Impacts and Outcomes

Table 13.1 Summary of Environmental Impacts Associated with the Project

Sensitive Receivers/ Assessment Points	Impact Prediction Results (Without Mitigation)	Key Relevant Standards/ Criteria	Extent of Exceedance (Without Mitigation)	Impact Avoidance Measures/ Mitigation Measures	Residual Impacts (After Implementation of Mitigation Measures)
Air Quality Impact
Construction Phase
Existing ASRs are industrial buildings, commercial buildings, parks at Kowloon Bay and Kwun Tong and the industrial buildings, residential buildings and sitting area at Cha Kwo Ling. The planned ASRs are the Commercial, Comprehensive Development Area, Residential, Government, Institution or Community, Open Space and Other Specified Uses of Kai Tak Future Development. A total of 10 Air Sensitive Receivers (ASRs) have been identified for the construction phase assessment shown in Figures 4.1a and 4.1b, summarised in Table 4.4.	• Maximum predicted 1-hour and 24-hour averaged results of the worst case Tier 1 screening at representative ASRs are 570 µg/m³ and 169 µg/m³ respectively. • The predicted 1-hour and 24-hour results for the representative ASR CKL3 for the Tier 2 focused Cha Kwo Ling assessment area showed no exceedances of the criterion. There is a small area with exceedance on the contour plots but this comprises the works areas of the TKO-LTT project where no ASRs are located and therefore the dust impacts are considered as insignificant.. • Maximum predicted annual average TSP concentrations at representative ASRs is 76.5µg/m³ which indicates that all ASRs are in full compliance with the criteria.	• Annexes 4 and 12 of EIAO-TM; • 1-hour, 24-hour and annual averages for TSP; and • Air Quality Objectives (AQOs)	• Maximum predicted 1-hour averaged TSP result of Tier 1 exceeds EIAO-TM (1hr) criterion by up to 4031 µg/m³ • Maximum predicted 24-hour averaged TSP result of Tier 1exceeds AQO (24-hr) criterion by up to 1166 µg/m³ Maximum predicted annual averaged TSP result of Tier 1exceeds AQO (Annual) criterion by up to 95.2 µg/m³ • No exceedances for maximum predicted 1-hour and 24-hour TSP Concentrations of Tier 2	• Watering of the construction areas 12 times per day to reduce dust emissions by 91.7%, with reference to the “Control of Open Fugitive Dust Sources” (USEPA AP-42). The amount of water to be applied would be 0.91L/m2 for the respective watering frequency; • Dust enclosures with watering would be provided along the loading ramps and conveyor belts for unloading the C&D materials to the barge for dust suppression; • 3-sided barriers around the stockpiling areas WA3 and WA4; • The dust control measures detailed below shall also be incorporated into the Contract Specification where practicable as an integral part of good construction practice: -Use of regular watering to reduce dust emissions from exposed site surfaces and unpaved roads, particularly during dry weather; -Use of frequent watering for particularly dusty construction areas and areas close to ASRs; -Side enclosure and covering of any aggregate or dusty material storage piles to reduce emissions. Where this is not practicable owing to frequent usage, watering shall be applied to aggregate fines; -Open stockpiles shall be avoided or covered. Prevent placing dusty material storage piles near ASRs; -Tarpaulin covering of all dusty vehicle loads transported to, from and between site locations; -Establishment and use of vehicle wheel and body washing facilities at the exit points of the site; -Imposition of speed controls for vehicles on unpaved site roads, 8 km per hour is the recommended limit; -Routing of vehicles and position of construction plant should be at the maximum possible distance from ASRs; -Every stock of more than 20 bags of cement or dry pulverised fuel ash (PFA) should be covered entirely by impervious sheeting or placed in an area sheltered on the top and the 3 sides; -Cement or dry PFA delivered in bulk should be stored in a closed silo fitted with an audible high level alarm which is interlocked with the material filling line and no overfilling is allowed; and -Loading, unloading, transfer, handling or storage of bulk cement or dry PFA should be carried out in a totally enclosed system or facility, and any vent or exhaust should be fitted with an effective fabric filter or equivalent air pollution control system.	• No irreversible adverse residual impacts will be anticipated.
Operational Phase
Existing ASRs are industrial buildings, commercial buildings, parks at Kowloon Bay and Kwun Tong and the industrial buildings, residential buildings and sitting area at Cha Kwo Ling. The planned ASRs are the Commercial, Comprehensive Development Area, Residential, Government, Institution or Community, Open Space and Other Specified Uses of Kai Tak Future Development. A total of 25 Air Sensitive Receivers (ASRs) have been identified for the operational phase assessment shown in Figures 4.2a and 4.2b, summarised in Table 4.4.	• Predicted 1-hour average NO₂ Concentration at 1.5m above ground level: 114 - 199 µg/m³. • Predicted 24-hour average NO₂ Concentration at 1.5m above ground level: 75 - 95 µg/m^3. • Predicted annual average NO₂ Concentration at 1.5m above ground level: 64.5 – 74.7 µg/m³. • Predicted 24-hour Average RSP Concentration at 1.5m above ground level: 55 - 61 µg/m^3. • Predicted annual average RSP Concentration at 1.5m above ground level: 50.2 -53.3 µg/m³.	• Annexes 4 and 12 of EIAO-TM; • Hourly, 24-hour and Annual NO2 and RSP Concentrations; • AQOs; and • Tunnel Air Quality Guidelines specified under the EPD’s Practice Notes on Control of Air Pollution in Vehicle Tunnel 1995.	• No exceedances of the NO₂ or RSP AQOs are predicted.	• No mitigation measures are required.	• No adverse residual impacts are expected to occur.
Airborne Noise
Construction Phase
There are no existing NSRs within the South Apron area. Existing NSRs are residential village houses in the Cha Kwo Ling village, mid-rise residential developments in Cha Kwo Ling and the Tin Hau Temple. Existing and planned future NSRs have been identified at both the South Apron and in Cha Kwo Ling. The selected NSRs for the construction phase are shown in Figures 5.1a and 5.1b.	• Maximum Predicted Construction Noise Level ranged from 69dB(A) to 90 dB(A)	• Annex 5 of the EIAO-TM for non-restricted hours: 75dB(A) for domestic premises and hotels, and 70dB(A) during normal hours for education institutions including kindergartens (65dB(A) during examination periods), nurseries and all other places where unaided voice communication is required.	• Exceed the relevant criteria by up to 15dB(A).	• Use of quieter plant, including Quality Powered Mechanical Equipment (QPME) is specified for the list of equipment; • Use of temporary or fixed noise barriers with a surface density of at least 10kg/m2 to screen noise from movable and stationary plant; • Use of enclosures with covers at top and three sides and a surface density of at least 10kg/m2 to screen noise from generally static noisy plant such as air compressors; • Use of acoustic fabric for the silent piling system, drill rigs, rock drills etc.; • Proper fitting of silencers and mufflers on the ventilation fans; and • Implementation of good site practice.	• The mitigated predicted maximum noise level at all NSRs reduced to within the 75dB(A) noise criteria.
Operational Phase (Traffic Noise)
• Four future hospital developments and a residential development at the South Apron, and village houses at Cha Kwo Ling Village and two future residential developments at ex-Cha Kwo Ling Kaolin Mine Site and Yau Tong Bay (refer to Figures 5.2a and 5.2b)	• Without noise mitigation measures, the predicted noise levels would be in the range of 66.4 to 80.2 dB(A)	• Annex 5 of EIAO-TM; and	• No exceedances are predicted.	• No direct mitigation measures are required.	• Adverse residual impacts would not be anticipated
Operational Phase (Fixed Noise)
• Four future hospital developments and a residential development at the South Apron, and village houses at Cha Kwo Ling Village and two future residential developments at ex-Cha Kwo Ling Kaolin Mine Site and Yau Tong Bay (refer to Figures 5.2a and 5.2b)	• The operational fixed plant noise impacts at the identified NSRs have been predicted to comply with the respective criteria and adverse fixed noise impacts are not anticipated.	• Annex 5 of EIAO-TM: ANL-5dB(A) or prevailing noise level.	• No exceedances are predicted.	• No direct mitigation measures are required.	• Adverse residual impacts are not anticipated.
Ground-borne Noise
Construction Phase
A future residential development at the South Apron in Kai Tak, and village houses at Cha Kwo Ling Village (refer to Figures 5.1a and 5.1b)	• No exceedances are predicted.	• Annex 5 of the EIAO-TM for periods between 0700-1900 (except General Holiday & Sunday); The criteria for noise transmitted primarily through the structural elements of the building or buildings should be 10dB(A) less than the relevant acceptable noise level (ANL).	• No exceedances are predicted.	• The advancing speed of the TBM should be restricted to 2m/hr in order to ensure compliance with the daytime ground-borne noise limits.	• Adverse residual impacts would not be expected.
Water Quality
Construction Phase
15 WSRs are identified (refer to Figure 6.2 and Table 6.5)	• Potential water pollution sources have been identified as construction run-off, wastewater discharge from tunnelling and excavation, groundwater hydrology, contaminated groundwater, sewage effluent, accidental spillages and waste construction materials. • No disturbance to the marine waters or seabed will occur	• EIAO-TM; • WPCO; • WDO; and • ProPECC PN 1/94.	• No exceedances are predicted.	• A list of construction phase mitigation measures including providing perimeter drains, sand/silt removal facilities and oil interceptors, covering excavated and construction materials and spill response plans (refer to Section 6.4.8) was proposed for controlling and minimizing water quality impacts during construction phase; and • Construction activities should be subject to a routine audit programme throughout the construction period.	• Impacts of construction site runoff will be reduced to an acceptable level.
Operational Phase
15 WSRs are identified (refer to Figure 6.2 and Table 6.5)	• Impacts may be associated with tunnel run-off, surface road run-off, sewage from ventilation buildings and accidental spillage.	• WPCO	• No exceedances are predicted.	• The road drainage in the tunnel should pass through oil interceptors to remove oil, and grease before being discharged into the public storm water drainage system; • Silt traps and oil interceptors should be cleaned and maintained regularly; and • The oily contents of oil interceptors should be transferred to an appropriate disposal facility, or to be collected for reuse, if possible.	• No adverse water quality impacts are predicted.
Marine Ecology
Construction Phase
Eastern Buffer Water Control Zone (WCZ), the Victoria Harbour WCZ and the Western Buffer WCZ and other area likely to be impacted by the Project (refer to Figure 6.1)	• The ecological value of the intertidal habitats to be temporarily lost is generally considered to be very low, does not containing any species of conservation interest and the duration of any impact is temporary and reversible in nature. • Site run-off may lead to temporary water quality issues and an increase in local suspended solids for a short period of time. • Insignificant effects of increased marine traffic would be anticipated.	• Annex 8 of the TM-EIAO; • Marine Parks Ordinance (Cap. 476); • Wild Animals Protection Ordinance (Cap. 170); • Protection of Endangered Species of Animals and Plants Ordinance (Cap. 586); • Town Planning Ordinance (Cap. 131); • Hong Kong Planning Standards and Guidelines Chapter 10 (HKPSG); • The World Conservation Union IUCN; • United Nations Convention on Biodiversity; and • Convention on the International Trade in Endangered Species of Flora and Fauna (CITES)	• Not applicable.	• Good construction practice measures have been recommended to be implemented as follows: • avoid damage and disturbance to the remaining and surrounding natural habitat; • placement of equipment in designated areas within the existing disturbed land; • spoil heaps should be covered at all times; • construction activities should be restricted to the designated works areas; and • disturbed areas to be reinstated immediately after completion of the works.	• No long-term, unacceptable residual ecological impacts to marine ecological habitats and associated wildlife.
Operational Phase
Eastern Buffer Water Control Zone (WCZ), the Victoria Harbour WCZ and the Western Buffer WCZ and other area likely to be impacted by the Project (refer to Figure 6.1)	• No direct impacts are anticipated • Indirect impacts resulting from the deterioration of water quality.	• As for construction phase above.	• Not applicable.	• No specific mitigation measures are required; and • Implementation of the water quality mitigation measures recommended in the water quality impact assessment.	• No long-term, unacceptable residual ecological impacts to marine ecological habitats and associated wildlife.
Fisheries
Construction Phase
Victoria Harbour Water Control Zone (WCZ), Western Buffer WCZ and Eastern Buffer WCZ (refer to Figure 6.1)	• No significant impacts to fisheries are anticipated	• Annex 9 and Annex 17 of EIAO-TM	• Not applicable.	• No specific mitigation measures are required. • Construction run-off control measures will be implemented.	• No adverse water quality impacts are predicted.
Operational Phase
Victoria Harbour Water Control Zone (WCZ), Western Buffer WCZ and Eastern Buffer WCZ (refer to Figure 6.1)	• No significant impacts to fisheries are anticipated	• Annex 9 and Annex 17 of EIAO-TM	• Not applicable.	• No specific mitigation measures are required.	• No adverse water quality impacts are predicted.
Landscape and Visual
Construction Phase
Landscape Resources (LRs) and Landscape Character Area (LCAs) within the Study Area Visually Sensitive Receivers (VSRs) within the Primary Zone of Visual Influence	• Moderate to slight (Adverse) significance on LRs. • Moderate to slight (Adverse) significance on LCAs. • Moderate/substantial to insubstantial (Adverse) significance on VSRs. • 98 trees will be impacted due to the construction of Project. • 66 trees to be felled and 31 trees to be transplanted. • 5029 square meters of planting areas and a temporary loss of 75,300 square metres of hard standing which will be temporarily lost in the construction phase, and an permanent loss of 8500 square meters of hard standing within the operation phase (Western Works Area). • Loss of one tree and 21,500 square metres of hard standing which will be temporarily lost in the construction phase (Eastern Works Area).	• EIAO (Cap.499.S.16) and the TM on EIA Process, particularly Annexes 10 and 18; • EIAO Guidance Note 8/2010; • Protection of Endangered Species of Animals And Plants Ordinance (Cap 586); • Town Planning Ordinance (Cap 131); • Protection of the Harbour Ordinance (Cap 531); • Hong Kong Planning Standards and Guidelines (HKPSG); • Study on Landscape Value Mapping of Hong Kong; • Land Administration Office Instruction (LAOI) Section D-12 - Tree Preservation; • WBTC No. 25/92 - Allocation of Space for Urban Street Trees; • WBTC No. 7/2002 - Tree Planting in Public Works; • ETWB TC(W) No. 13/2003 - Guidelines and Procedures for Environmental Impact Assessment of Government Projects and Proposals; • ETWB TC(W) No. 13/2003A - Guidelines and Procedures for Environmental Impact Assessment of Government Projects and Proposals; Planning for Provision of Noise Barriers • ETWB TCW No. 2/2004 - Maintenance of Vegetation and Hard Landscape Features; • ETWB TCW No. 29/2004 - Registration of Old and Valuable Trees (OVTs), and Guidelines for their Preservation; • ETWB TCW No. 8/2005 - Aesthetics Design of Ancillary Buildings in Engineering Projects; • ETWB No. 36/ 2004 - Advisory Committee on the Appearance of Bridges and Associated Structures (ACABAS); • ETWB TCW No. 10/2005 - Planting on Footbridges and Flyovers; • ETWB TCW No. 3/2006 - Tree Preservation; • DEVB TCW No. 2/2013 - Greening on Footbridges And Flyovers • DEVB TCW No. 3/2013 – Site Coverage of Greenery on Footbridges And Flyovers • Hyd - Structures Design Guidelines for highways & Railways, Third Edition. Section 17;	• Moderate to slight (Adverse) significance on LRs. • Moderate to slight (Adverse) significance on LCAs. • significance on LCAs. • Moderate/ substantial to insubstantial (Adverse) significance on VSRs. • 98 trees will be impacted due to the construction of Project. • 66 trees to be felled and 31 trees to be transplanted. • 5029 square meters of planting areas and a temporary loss of 75,300 square metres of hard standing which will be temporarily lost in the construction phase, and an permanent loss of 8500 square meters of hard standing within the operation phase (Western Works Area). • Loss of one tree and 21,500 square metres of hard standing which will be temporarily lost in the construction phase (Eastern Works Area). •	• All works shall be carefully designed to minimize impacts on existing landscape resources and visually sensitive receivers. Existing trees within works area shall be retained and protected. • Existing trees of good quality and condition that are unavoidably affected by the works should be transplanted. · Large temporary stockpiles of excavated material shall be covered with unobtrusive sheeting to prevent dust and dirt spreading to adjacent landscape areas and vegetation, and to create a neat and tidy visual appearance. · Construction plant and building material shall be orderly and carefully stored in order to create a neat and tidy visual appearance. · Erection of decorative screen hoarding should be designed to be compatible with the existing urban context. All lighting in construction site shall be carefully controlled to minimize light pollution and night-time glare to nearby residences and GIC user. The contractor shall consider other security measures, which shall minimize the visual impacts.	• Moderate to slight (Adverse) significance on LRs. • Moderate to slight (Adverse) significance on LCAs. • Moderate to insubstantial (Adverse) significance to VSRs.
Operational Phase
Landscape Resources (LRs) and Landscape Character Area (LCAs) within the Study Area Visually Sensitive Receivers (VSRs) within the Primary Zone of Visual Influence	• Slight to insubstantial (Beneficial) significance on LRs. • Slight to insubstantial (Beneficial) significance on LCAs. • Moderate to insubstantial (Beneficial) significance on VSRs. •	• As above for operational phase.	• Slight to insubstantial (Beneficial) significance on LRs. • Slight to insubstantial (Beneficial) significance on LCAs. • Moderate to insubstantial (Beneficial) significance on VSRs	• Compensatory tree planting shall be incorporated along all roadside amenity areas affected by the construction works. The required numbers and locations of compensatory trees shall be determined and agreed with the Government during Tree Removal Application process under ETWB TCW No. 3/2006. • Compensatory tree planting shall be incorporated by the Project. The required numbers of compensatory trees shall follow the requirements of ETWB TCW No. 3/2006. Loss of amenity area adjacent to the Kwun Tong By-pass and planting areas in KTD South Apron will be mitigated by the creation of the Kai Tak South Apron: Amenity Area, which will be equal to or larger than the current provision. • Trees, shrubs and climbers shall be planted to soften and screen proposed roads, central medians and associated structures, and to enhance streetscape greening. • All works area, excavated area and disturbed area for tunnel construction and temporary road diversion or any other proposed works shall be reinstated to former conditions or better, with reasonable landscape treatment and to the satisfaction of the relevant Government departments. • Tunnel portals and all above ground structures shall be sensitively designed to ensure the element with colour, texture and tonal quality being compatible to the existing urban context. Trees and shrub planting to minimize the potential adverse landscape and visual impacts shall be included where space permits. Roof top greening and vertical greening shall also be provided.	• Slight to insubstantial (Beneficial) significance to LRs on Day 1 and Slight to insubstantial (Beneficial) to LRs at Year 10. • Slight to insubstantial (Beneficial) significance to LCAs on Day 1 and Slight to insubstantial (Beneficial) to LRs at Year 10. • Moderate to insubstantial (Beneficial) significance on VSRs on Day 1 and Slight to insubstantial (Beneficial) to LRs at Year 10. • 152 compensatory trees to be planted, 4900 square meters of amenity area to be provided within the Kai Tak • South Apron. 15,740 square meters of planting ara to be provided(trees and, shrubs) Sensitive architectural treatments to the Ventilation and Tunnel Portal Buildings including green roof and vertical greening.
Culture Heritage
Construction Phase
The terrestrial and marine archaeology assessments did not identify any areas of archaeological potential The built heritage survey has identified 11 buildings in Cha Kwo Ling.	• No impacts are predicted. • No adverse impacts to any of the buildings have been identified.	• Annexes 10 and 19 of EIAO; • Chapter 10 of the HKPSG; and • Antiquities and Monuments Ordinance (AMO).	• Not applicable.	• No mitigation will be required	• No adverse impacts to any of the buildings have been identified.
Operational Phase
The terrestrial and marine archaeology assessments did not identify any areas of archaeological potential The built heritage survey has identified 11 buildings in Cha Kwo Ling.	• No terrestrial or marine archaeological potential and no impacts are predicted. • No adverse impacts to any of the buildings have been identified.	• Annexes 10 and 19 of EIAO; • Chapter 10 of the HKPSG; and • Antiquities and Monuments Ordinance (AMO).	• Not applicable.	• No mitigation will be required	• No adverse impacts to any of the buildings have been identified.
Waste Management
Construction Phase
Near the Project Site, the waste transportation routes and the waste disposal site	• Excavated marine deposit (sediment) buried underneath the South Apron and Cha Kwo Ling works areas for the construction of cut-and-cover tunnel sections; • The majority of the soft C&D material, comprising sand fill, Grade III rock and below and alluvium, makes up approximately 1.15Mm3. The predicted surplus amount of this C&D material, in addition to the Grade II or above rock from the subsea tunnel, totally approximately 975,980m3; • Site clearance will likely comprise the 11,846m3 inert C&D materials • C&D waste which is not suitable for public fill; • Chemical waste; • Sewage; and • Approximately 1000m3 of general refuse will be generated. • Site clearance will generate inert materials in the form of soil, rock and concrete, in addition to non-inert C&D waste materials such as timber, paper, vegetation and plastic. • No marine sediment will be extracted from the marine waters. As such, the marine deposits to be generated will be restricted to the sediment located under the reclaimed land to be excavated during the land-based works at the South Apron and Cha Kwo Ling.	• Environmental Impact Assessment Ordinance (Cap 499); • Waste Disposal (Amendment) Ordinance (Cap 354); • Dumping at Sea Ordinance (Cap 466); • Land (Miscellaneous Provisions) Ordinance (Cap 28); • Public Health and Municipal Service Ordinance (Cap 132) – Public Cleansing and Prevention of Nuisances By-laws; • Waste Disposal (Charges for Disposal of Construction Waste) Regulation (Cap 354); • Waste Disposal (Chemical Waste) (General) Regulation (Cap 354); • Environment, Transport and Works Bureau Technical Circular (Works) No.34/2002 Management of Dredged /Excavated Sediment; and • Works Bureau Technical Circular (WBTC) No. 12/2000 Fill Management.	• Not applicable.	• Mitigation measures are required to ensure the proper handling, storage, transportation and disposal of waste is carried out. Also measures to ensure that the generation of waste is avoided and minimised and that waste materials are recycled and treated as far as practicable. (refer to section 11.4.8.1) • During construction phase, regular site inspections and supervision of the waste management procedures shall be undertaken as part of the EM&A procedures. • Disposal options have been proposed. (refer to Table 11.8)	• No adverse residual impacts would be anticipated
Operational Phase
Near the Project Site, the waste transportation routes and the waste disposal site	• No significant quantities of waste are expected. • The quantities of general refuse arising from the Project would be low and mainly arise from the plant maintenance workshops associated with the ventilation buildings. • The quantities of chemical waste such as lubrication oils, used batteries, paints and solvents are likely to be generated but the quantities would be small and insignificant. • Operational sewage will be generated but in small quantities.	• Waste Disposal (Amendment) Ordinance (Cap 354) • Waste Disposal (Chemical Waste) (General) Regulation (Cap 354);	• Not applicable.	• No significant waste implications are predicted	• No adverse residual impacts would be anticipated
Contaminated Land
Construction Phase
• Construction workers would be prone to exposure to any potential contaminated materials during the construction phase when conducting excavation of the concerned contaminated sites. The principle exposure routes would include: -Direct ingestion of contaminated materials through eating or drinking on-site; and -Dermal contact with contaminated materials. -A total of 53 soil samples and 13 groundwater samples were collected.	• No adverse impacts due to land contamination anticipated. in accordance to the site investigation during the EIA stage. • 2 borehole locations, EH1 and EH3, at which the SI works, were inaccessible during the site investigation due to site access constraints at Cheung Yip Street. • There may be potential land contamination hotspots at Works Area WA2. As this area has been inaccessible for conducting site investigation during the EIA stage, land contamination assessment has not been conducted.	• Practice Guide for Investigation and Remediation of Contaminated Land; • Guidance Note for Contaminated Land Assessment and Remediation; and • Guidance Manual for Use of Risk-Based Remediation Goals (RBRGs) for Contaminated Land Management.	• No exceedances of the RBRGs criteria for the land contamination.	• No specific mitigation measures are required in accordance to site investigation during the EIA stage. • Supplementary SI to complete the land contamination assessment for borehole locations EH1 and EH3 and further reconnaissance visits to WA2, would be conducted when these sites become accessible. A supplementary CAP, CAR and/or RAP and RR (if remediation work is necessary) should be submitted to EPD for endorsement before commencement of construction works at these sites.	• No adverse residual impacts are anticipated.
Operational Phase
• No sensitive receivers have been identified.	• Not applicable.	• Practice Guide for Investigation and Remediation of Contaminated Land; • Guidance Note for Contaminated Land Assessment and Remediation; and • Guidance Manual for Use of Risk-Based Remediation Goals (RBRGs) for Contaminated Land Management..	• Not applicable.	• Provided that the necessary remediation action and measures have been fully implemented, .no specific mitigation measures are required.	• Not applicable.

Table 13.2 Summary of Key Environmental Outcomes

Area/Issue	Environmental Outcomes and Mitigation Measures
Trunk Road T2 Project	As a part of the strategic road network within the South East Kowloon Development, Route 6 forms an east west express link between West Kowloon and Tseung Kwan O. Route 6 comprises the Central Kowloon Route (CKR), Trunk Road T2 and Tseung Kwan O–Lam Tin Tunnel (TKO-LTT). This Assignment covers the provision of the Trunk Road T2 and the main elements of the works comprise the construction of Trunk Road T2 and its connections with the CKR at the north apron area and the TKO-LTT to the south in the Cha Kwo Ling area. The preferred Trunk Road T2 will comprise: 1. a dual two-lane trunk road of approximately 3.0km long with about 2.7km of the trunk road in form of tunnel; 2. ventilation and administration buildings and a traffic control and surveillance system; and 3. associated civil, electrical, mechanical, landscaping and environmental protection and mitigation works.
Environmentally Friendly Design Recommended	The preferred alignment for the Trunk Road T2 provides the best environmental option resulting in significantly less environmental impacts, including reduced quantities of excavated material, no dredging of potentially contaminated marine deposits, reduced impacts on fisheries, water quality and marine ecology and operation noise and air quality benefits. In addition, the TBM method has been selected as the preferred method of tunnel construction, which also, has notable environmental benefits. Air and Noise: As a sub-marine tunnel would be constructed by TBM method, noise and dust from this operation would be contained underground from the point of the launching shaft, minimising construction phase impacts to the environment on the South Apron, particularly for existing sensitive receivers (SRs) at the southern end of the alignment in Cha Kwo Ling. The operational air emissions would be vented via a high level shaft from the ventilation buildings, enhancing dispersion and resulting in low level impacts at the SRs at both the South Apron and Cha Kwo Ling. Water Quality: As TBM is used to construct the Trunk Road T2, dredging and reclamation is not required. The TBM tunnel would be deep enough to avoid the seabed and marine deposits. It would be avoided to pass under the existing breakwaters to the KTTS and the existing twin submarine outfalls of the KTSTW and hence avoid the need to excavate and temporarily re-provide both of these features and thus reduce further disturbance to the seabed and marine sediment deposits. The TBM would also be launched and received from shafts on land which would also avoid deterioration of water quality and any disturbance to the seawalls and marine environment. Construction run-off from the land based works could potentially affect the marine waters if not controlled. Marine Ecology and Fisheries: As the Trunk Road T2 project will be built on largely developed or disturbed land, terrestrial ecological impacts are not expected. As the Trunk Road T2 project is largely in tunnel to be constructed by TBM, there would be no disturbance to the marine environment. LVIA: On completion of the project, as the majority of the Trunk Road T2 project works is either underground or used for temporary construction and associated works, except for the Ventilation Building and Tunnel Portal Buildings. In the operational phase these impacts will be mitigated by provision of new roadside trees and shrub planting and a new public amenity area, termed the Kai Tak South Apron Public Open Space. In addition, the aforementioned buildings and portal will be mitigated by sensitive and contemporary architectural detailing, including green roofs, textual and tonal finishes, and screen planting. These are envisioned to blend the Project into the proposed surrounding landscape. It is considered that the residual landscape and visual impacts of the proposed Project are acceptable with mitigation measures during construction and operational phases. Cultural Heritage: Study of the marine and terrestrial archaeology did not reveal any areas of archaeological potential in the Trunk Road T2 area and as such no impacts are expected. In terms of built heritage, the only resources are located in the Cha Kwo Ling Village but these will not be significantly affected and no mitigation is required. Waste Management: The bulk material constructed by TBM from the sub-sea tunnel will be alluvial material which is not contaminated and can be reused in other projects once dewatered. Some uncontaminated marine sediments will be produced from the land based foundation works but it is proposed to treat and reuse this material on site.
Population and Environmentally Sensitive Areas Protected	With the adoption of the environmentally friendly design in the preferred option, the major environmental sensitive receivers will be protected. This preferred option is determined based on the comparison of the environmental benefits and dis-benefits of the various options and alternatives and has been selected on the basis that it minimises environmental impacts and presents overall environmental benefits over the other options and is considered the optimum scheme from an environmental perspective.
Air Quality	Construction Dust Impact: Potential air quality impacts from the construction works for the Trunk Road T2 construction works would mainly be related to construction dust from excavation, materials handling, spoil removal and wind erosion. Without mitigation measures, dust impacts to the nearby ASRs will exceed the respective TSP criteria. However, with the implementation of hourly watering of all exposed areas and mitigation measures as defined in the Air Pollution Control (Construction Dust) Regulation, provision of dust enclosures at the conveyor belts, 3-sided barriers at the stockpiling areas and good site practices, adverse 1-hour, 24-hour or annual residual impacts would not occur. The predicted air impact would be unlikely to induce public health concern. Operational Impact: Potential air quality impact during the operational phase of Trunk Road T2 and other major existing road networks would be dominated by vehicle gaseous emissions, mainly NO₂ and RSP, either from open roads, or via the proposed tunnel portals and ventilation buildings. No exceedances of the hourly, 24 hourly and annual NO₂ or 24 hourly and annual RSP AQOs are predicted and as such, no mitigation measures are required. No adverse residual impacts during the operational phase are predicted.
Noise	Construction Air-borne Noise: Without mitigation, noise impacts are predicted to exceed the relevant criteria by up to 15dB(A). The high level of unmitigated construction noise impacts are due to the limited separation distance between the NSRs and the works sites. Mitigation measures are, therefore, recommended to reduce the noise levels to within the EIAO-TM noise criterion, including provision of quieter plants, silencers, noise barriers, enclosures and acoustic fabric. After these mitigation measures are adopted, the noise levels at all representative NSRs would meet the relevant noise criteria. No adverse residual impacts would be anticipated during the construction phase. However, construction air-borne noise monitoring would be required to ensure compliance with respective criteria. Construction Ground-borne Noise: With a 10dB(A) prediction safety factor, the daytime noise criteria of 65dB(A) is fulfilled at all the NSRs under unmitigated condition. In order to ensure compliance with the daytime ground-borne noise limits, the advancing speed of the TBM should be restricted to 2m/hr. Operation Fixed Plant Noise: The operation fixed plant noise impacts at the identified NSRs have been predicted to comply with the respective criteria and adverse fixed noise impacts are not anticipated. As such, no mitigation measures are required. However, prior to the operation of the Trunk Road T2 project, the Contractor should conduct noise commissioning tests for all major fixed noise sources to ensure the noise emission comply with the EIA report assessed scenario. Operation Traffic Noise: Exceedances of respective operational traffic noise are anticipated at some of the NSRs. However, the affected NSRs are anticipated to be equipped with centralised air conditioning systems and will, therefore, not rely on openable windows for ventilation. Thus, no direct mitigation measures are required.
Water Quality	Potential water pollution sources have been identified as construction run-off, wastewater discharge from tunnelling and excavation, contaminated groundwater, sewage effluent, accidental spillages and waste construction materials. Mitigation measures including providing perimeter drains, sand/silt removal facilities and oil interceptors, covering excavated and construction materials and spill response plans have been recommended to mitigate any adverse water quality impacts. Based on the implementation of the mitigation measures, no adverse water quality impacts are predicted. Operational phase water quality impacts may be associated with tunnel run-off, surface road run-off, sewage from ventilation buildings and accidental spillage. However, any impacts are considered negligible provided that the recommended mitigation measures are implemented and adverse water quality impacts are not predicted. No significant adverse residual impacts during the construction and operational phases are anticipated, provided that the above mitigation measures are implemented.
Marine Ecology	Construction Phase: In order to avoid the marine ecological impacts during construction phase, TBM method of tunnelling has been adopted instead of the IMT method. As such, there will be no permanent habitat loss predicted. The potential for construction stage site run-off may lead to temporary water quality issues and an increase in local suspended solids for a short period of time during construction phase. However, these impacts are predicted to be minor and can be further controlled by the implementation of the recommendations in the Water Quality Impact Assessment and ProPECC PN 1/94 Construction Site Drainage and, thus, they would be temporary and negligible with good site practices in place during the construction phase. With implementation of the mitigation measures, the Trunk Road T2 project would have no long-term, unacceptable residual ecological impacts to marine ecological habitats and associated wildlife during construction phase Operational Phase: Minor impacts to marine ecological resources due to potential accident spillages of chemical/oil and road surface run-off have been predicted as a result of the operation of the Trunk Road T2 project and no ecological specific mitigation measures are required. The implementation of the mitigation measures recommended in the Water Quality Impact Assessment, including provision of adequate drainage system with silt traps and oil interceptors, will help to minimise any impacts further.
Fisheries	No construction or operational impacts to the marine environment are predicted and, therefore, mitigation measures are not required for fisheries resources given that the water quality mitigation measures will be implemented as necessary.
Landscape and Visual	On completion of the Project, the majority of Trunk Road T2 is underground, except for the low rise (+17mPD) Ventilation Building, Tunnel Portal Building and refuse collection building. In the Western Works Area, there will be a temporary loss of 75,300 square metres and a permanent loss of 8500 square meters of hard standing and, 5029 square meters of planting areas will be permanently lost. This will be mitigated by 15,740 square meters of planting areas and 4,900 square meters of Amenity Area as referred to in the report as RE10 Kai Tak South Apron: Amenity Area. 98 trees will be impacted upon. 67 trees are recommended to be felled and 31 are proposed to be transplanted to a location that will be identified at a later stage of the project. Extensive compensatory planting will include 152 trees in accordance with ETWB TCW No. 3/2006 (refer to Figure 9.11.2). In the Eastern Works Area one tree and an approximate area of 21,500 square metres of hard standing will be lost. Mitigation for the felled tree has been included within the compensatory trees for the Western Works Area. The site will be reinstated and handed over for future development of Cha Kwo Ling Promenade Park under a separate project. Details of the landscape proposals for the Western Works Area will be reviewed within the detail design stage. It is considered there will be no substantial adverse landscape and visual impacts by the Project during the operation phase. Through the construction stage the following mitigation measures will be followed: (a) All works shall be carefully designed to minimize impacts on existing landscape resources and visually sensitive receivers. Existing trees within works area shall be retained and protected where practical. (b) Existing trees that are unavoidably affected by the works should be transplanted where practical. (c) Topsoil, where identified, shall be stripped and stored for re-use in the construction of the soft landscape works, wherever practicable. (d) The potential for soil erosion shall be reduced by minimizing the extent of vegetation disturbance on site and by providing a protective cover over newly exposed soil. (e) Large temporary stockpiles of excavated material shall be covered with unobtrusive sheeting to prevent dust and dirt spreading to adjacent landscape areas and vegetation, and to create a neat and tidy visual appearance. (f) Construction plant and building material shall be orderly and carefully stored in order to create a neat and tidy visual appearance. (g) Erection of decorative screen hoarding should be designed to be compatible with the existing urban context. (h) All lighting in construction sites shall be carefully controlled to minimize light pollution and night-time glare to nearby residences and GIC user. Through the operational phase the following mitigation measures will be implemented: (a) Provision of a new public open space, termed the Kai Tak South Apron Public Open Space. (b) Compensatory tree planting shall be incorporated along all roadside amenity areas affected by the construction works. The required numbers and locations of compensatory trees shall be determined and agreed with the Government during Tree Removal Application process under ETWB TCW No. 3/2006. (c) Compensatory tree planting shall be incorporated into any public open spaces affected by the construction works. The required numbers and locations of compensatory trees shall be determined and agreed with the Government during Tree Removal Application process under ETWB TCW No. 3/2006 (d) Trees and shrubs shall be planted to soften and screen proposed roads, central medians and associated structure, and to enhance streetscape greening. (e) All works areas, excavated area and disturbed area for tunnel construction and temporary road diversion or any other proposed works shall be reinstated to former conditions or better, with reasonable landscape treatment and to the satisfaction of the relevant Government departments. (f) The tunnel portal and refuse collection building would be sensitively designed and proposed to be no higher than 17mPD (Figures 9.12.1 – 9.12.4). Mitigation measures including vertical greening and tree planting are proposed to be provided. The overall visual impacts on the surrounding VSRs would not be significant and could be considered positive to a certain extent. The above mitigation measures for construction and operational phases will reduce landscape and visual impacts of the Project to acceptable levels.
Cultural Heritage	The terrestrial and marine archaeology assessments did not identify any areas of archaeological potential and no impacts are predicted. However, any antiquity or supposed antiquity discovered during the course of the excavation works will be reported to the AMO immediately. The built heritage survey identified 11 buildings in Cha Kwo Ling. However, no adverse impacts to any of the buildings have been identified during either the construction or operational phases of the project and no mitigation will be required.
Waste Management Implication and Land Contamination	The construction of the Trunk Road T2 will involve a number of activities which will generate waste that can be broadly be classified into distinct categories based on its nature and the options for disposal. These include: · Excavated marine deposit (sediment) buried underneath the South Apron works area for the construction of cut-and-cover tunnel sections; · Excavated C&D materials suitable for public fill, including the alluvium from the sub-marine tunnel construction; · C&D waste which is not suitable for public fill; · Chemical waste; · Sewage; and · General refuse. There are remaining SI works at EH1 & EH3 and further reconnaissance visits to inaccessible Works Area WA2 to be conducted when these sites become accessible. Supplementary CAP, CAR and/or RAP and RR (if remediation work is necessary) should be submitted to EPD for endorsement before commencement of construction works at these sites. With the implementation of the recommended mitigation measures, there would be no adverse residual impacts associated with the handling, storage, transportation or disposal of the waste generated by the Trunk Road T2 project during the construction and operational phases. As there were no exceedances of the criteria for the land contamination for the Trunk Road T2 project, there would be no adverse impacts due to land contamination anticipated.