1. introduction

Ove Arup & Partners (Arup) was commissioned by Kowloon Canton Railway Corporation (the Project Proponent) to undertake an Environmental Impact Assessment (EIA) of the proposed Kowloon Southern Link (KSL).

1.1 EIA Study Brief

The proposed KSL project is classified as a designated project under Schedule 2 of the Environmental Impact Assessment Ordinance (EIAO). In accordance with the requirements of Section 5(1) of the EIAO, a project profile (No. PP-160/2002) ^[1-1] was submitted to Environmental Protection Department (EPD) for the application of an EIA Study Brief on 21 January 2002. Pursuant to Section 5(7)(a) of the EIAO, EPD issued to the Project Proponent a study brief (ref: EIA Study Brief No: ESB-097/2002 dated March 2002) ^[1-2] to carry out an EIA study.

1.2 Background Information & Previous Studies

A preliminary assessment of the environmental issues of KSL and a study of the pros and cons of the 4 alignment options were provided in a Preliminary Project Feasibility Study of KSL completed in 2001^{[1-3] & [1-4]}. The key environmental issues of the proposed project and the considerations on the alignment options have been further elaborated and reviewed in this EIA Report (see Chapter 3).

1.3 Project Description

1.3.1 Key Elements

The Project Proponent proposes to construct and operate a new railway line as shown in Figure 1-1 to improve the accessibility to Tsim Sha Tsui (TST) and West Kowloon districts. The proposed 3.7km underground railway will connect the new KCRC East TST Station to the current West Rail (WR) Nam Cheong (NAC) Station, with its alignment running under Salisbury Road, Canton Road and the West Kowloon Reclamation area.

There were two stations originally planned along the KSL alignment, namely the Canton Road Station (CAR) and the West Kowloon Station (WKN). The plan for CAR has been deferred and there is also no confirmed implementation plan for any topside property development for the WKN. In addition, the originally proposed subway under Haiphong Road and/or Peking Road for connection between the existing MTR TST Station and the CAR has been shelved. Any future incorporation of a station at Canton Road shall be subject to consideration of material change to a designated project. If any Essential Project Infrastructure Works, such as subway connection, is to be implemented in the future as part of the railway upgrade, the EIAO framework will apply to determine whether it constitutes a material change.

Two ventilation / plant buildings would be required along the alignment to provide tunnel cooling and ventilation: Yau Mai Tei (YMT) Ventilation Building is located between the WKN and the WR NAC; and Canton Road Plant Building (CRPB) is located at the junction of Kowloon Park Drive and Canton Road. Necessary mechanical plant items will be accommodated within the WKN and at the ventilation / plant buildings.

In addition, a freshwater cooling facility will be provided to serve the environmental control requirements for WKN and the tunnels. Neither reclamation nor dredging works are anticipated for KSL at this stage.

Detailed descriptions of the project elements and their corresponding construction methodologies are presented in Chapter 4.

1.3.2 Construction Programme

The construction work will commence in early 2005 and is scheduled to be completed by late 2007. Testing and commissioning of the railway system will immediately follow with target completion for operation in late 2008 / early 2009.

1.3.3 Train Services

Upon completion of KSL, the WR train service will terminate at Hung Hom. Train services will extend through the nighttime period on special occasions to cater for the needs during festivals (for example, Christmas Eve, Chinese New Year, etc.). WR type Electric Multiple Units (EMUs) will be deployed on KSL to serve passengers. Maintenance trains are organised only for emergency and during scheduled services.

1.4 Scenarios for With and Without the Project

The project will create an efficient transportation link between the West Kowloon area and TST, and provide access for the public to an environmental friendly transport system for travel connection between WR, East Rail and MTR. It offers an alternative route for cross-harbour passengers originated from the North West New Territories and will greatly enhance the public transport infrastructure network of Sham Shui Po and Yau Tsim Mong districts. Population from these two districts as well as tourists travelling from the TST area will be directly benefited.

Inevitably, temporary environmental impacts will be induced on the existing environment along the alignment from some of the construction activities. Environmental friendly construction methodologies and appropriate mitigation measures will be implemented to ensure all the impacts are minimized to acceptable levels (see Chapters 4 –12 for details).

When completed and in operation, permanent changes to the environment and controlled acceptable impacts may be experienced by individuals. However, in the absence of KSL, passengers travelling between WR NAC and TST will solely rely on road-based transport, which will result in increasing road traffic and contribution to additional noise and air pollution issues local to the districts. Also, cross-harbour passengers originated from Northwest New Territories community on East Rail will suffer a longer journey time on travelling.

1.5 Concurrent Projects & Essential Public Infrastructure Works

There are several confirmed projects in the vicinity of KSL works area, as summarised in Table 1-1. At this stage, consideration of concurrent projects for cumulative environmental impacts will only take into account those with confirmed implementation programme.

Table 1-1 : Confirmed projects identified in the vicinity of KSL works area and key dates

	Key Date for Construction
Project	Commencement	Completion
KCRC East Rail Extension	Jan 2001 ^[1]	Mid 2004 ^[1]
Salisbury Road Underpass and Associated Road Improvement Works including Middle Road Circulation System	Early 2002 ^[2]	Late 2004 ^[2]
Modifications to MTRC TST Station	April 2002	End 2005 ^[3]
FMPHQ	Early 2004 ^[4]	Mid 2006 ^[4]
WKCD	April 2007^[5]	2011-2013^[5]
Post Secondary College at junction of Hoi Ting Road & Hoi Wang Road	2005/2006^[6]	Not available
Cultural Square Development at Salisbury Road	2005 ^[7]	2007^[7]
Pedestrian Piazza	2007^[8]	2008^[8]
Road D1/D1A (potentially entrusted to KCRC projects)	Tentatively in late 2007^[7]	-
Road D12 (eastern section to be potentially entrusted to KCRC projects)	Tentatively in late 2007 (for potentially entrusted work)^[7]	-
Hong Kong Girl Guides Association Headquarter	Early 2005^[8]	Late 2007^[8]
Secondary school at Yau Cheung Road	2007/08^[8]	2009/10^[8]
China Light Power Electricity Substation	Late 2004^[8]	2007^[8]

Note:

[1] It is confirmed by the Project Proponent that all construction of ERE will be completed before commencement of the KSL.

[2] It is confirmed by HyD that all Salisbury Road widening works have been completed in August 2002. Construction of the entrusted works to KCRC ERE will be completed before commencement of the KSL.

[3] Information as extracted from EIAO web site.

[4] Reference has been made to Project Profile DIR-094/2003 submitted for application for direct EP for FMPHQ.

[5] Based on “Invitation for Proposal” for West Kowloon Cultural District.

[6] The commencement date was advised by Education and Manpower Bureau.

[7] The tentative programme was advised by the Project Proponent.

[8] Based on discussion with the respective project proponents.

It is noted that the civil construction works for the following three projects will be completed before commencement of the construction of KSL and hence there will be no concurrent activities.

(1) KCRC East Rail Extension

· KCRC East Rail Extension will be completed before commencement of KSL works.

(2) Salisbury Road underpass

· For Salisbury Road underpass, the major excavation works are entrusted to KCRC East Rail Extension (ERE), which will be completed before commencement of the KSL while the remaining Salisbury Road widening works have already been completed by Highways Department (HyD) in August 2002.

(3) Modification to MTRC TST Station

· According to the latest information from the approved EIA of the “Modification to MTRC TST Station”^[1-5], all backfilling and road reinstatement work for the MTR Station in Nathan Road will be completed by late 2004. The remaining works are electrical and mechanical (E&M) fitting out, and architectural and builders works & finishes (ABWF) for concourses only which will be completed by end of 2005. Overlapping of civil construction works with KSL is not anticipated.

There are ten possible concurrent projects and they are described as follows (see Figures 1-2-1 and 1-2-2). Their cumulative environmental impacts are addressed in the respective chapters of this report.

(1) Former Marine Police Headquarters

· According to the recent approved Project Profile (DIR-094/2003) submitted for application for direct EP for the “Development at Former Marine Police Headquarters KIL11161” ^[1-6], the proposed construction period of the FMPHQ site is planned for 30 months and will commence in early 2004. It will overlap with the KSL construction.

· A summary of the construction activities during the overlapping period of the two projects is given in Table 1-2.

Table 1-2: Construction activities during the overlapping construction period with FMPHQ

	Construction Activities
Period	KSL ^[1]	FMPHQ
Mar 05 – May 05	Utilities diversion along Salisbury Road & at the Emergency Egress Point (EEP) and construction of access shaft	Remaining excavation
Jun 05 – Mar 06	Remaining utilities diversion work at EEP and construction of access shaft Temporary wall & decking along Salisbury Road & at EEP and construction of access shaft Excavation at EEP and construction of access shaft	Remaining excavation + Superstructure work
Apr 06 – Oct 06	Excavation along Salisbury Road	Superstructure work

Note:

[1] Refer to Chapter 4 for the construction programme and methodology.

(2) West Kowloon Cultural District (WKCD)

· The latest information for WKCD at the time of preparing this EIA is available from the government website. It is noted that the proposal for WKCD has been submitted in middle of June 2004. According to Addendum No. 3 to the Invitation for Proposal for the WKCD ^[1-7] issued on 30 March 2004, the construction of the WKCD is anticipated to commence in April 2007, with completion and operation of the core arts and cultural facilities in phases by 2011 to 2013. There is currently no available information on the construction programme / methododlogy / phasing and its cumulative environmental impacts will be addressed by reasonable assumptions.

· The major KSL construction activities in the vicinity of WKCD are the construction of WKN which will be undertaken from March 2005 to December 2007. In accordance with the construction programme of KSL, all excavation works for WKN will be completed by September 2006. The remaining works are construction of superstructure (to be completed by September 2007) and station fit-out works. Hence, the overlapping period between the WKCD and the superstructure construction of WKN would be relatively short from May to Sept 2007 (and possibly shorter or even without overlapping at all in consideration of 2-3 months of mobilisation period of WKCD Contractor to be on site).

(3) Post-secondary College

· It is advised by Education and Manpower Bureau that construction of the Post-secondary College at junction of Hoi Ting Road and Hoi Wang Road will commence in 2005/2006. It will overlap with the construction of WKN northern tunnel for KSL. Similar to WKCD, there currently is no available information on construction programme and methododology, its cumulative environmental impacts will be addressed by making reasonable assumptions.

(4) Cultural Square Development

· The proposed Cultural Square Development is located at Salisbury Road and it is noted that the project will be constructed concurrently with the Salisbury Road tunnel section of the KSL from 2005 to 2007. There is currently no available information on construction programme and methodology, and its cumulative environmental impacts will be addressed by reasonable assumptions.

(5) Pedestrian Piazza

· The proposed pedestrian piazza is located at the existing Star Ferry Public Transport Interchange (PTI). Subject to the relocation of the Star Ferry PTI in 2006/2007, the works for the open plaza would commence in 2007 for completion in 2008. Its construction will be undertaken concurrently with the Salisbury Road tunnel section of the KSL in 2007. There is currently no available information on construction programme and methodology, and its cumulative environmental impacts will be addressed by reasonable assumptions.

(6) Road D12

· The proposed Road D12 would come into operation at the same time as KSL in 2008/2009. There is no currently available information on construction programme and methodology, and its cumulative environmental impacts will be addressed by reasonable assumptions. However, for the eastern section of Road D12, which lies partially within the gazettal boundary of the KSL project, it is advised that the construction work will potentially be entrusted to KCRC as a separate project, subject to confirmation. A separate Environmental Permit (EP) will be applied from EPD for construction and operation of the roadworks. The Project Proponent would schedule the construction works and allow programme phrasing to avoid major concurrent activities to be undertaken simultaneously in the vicinity. Construction of roadworks is likely to commence in late 2007 when all civil works of WKN are completed. Cumulative impacts are therefore not anticipated.

· The roadwork for the western section of Road D12 has already completed.

(7) Road D1/D1A

· The proposed Road D1/D1A would come into operation at the same time as KSL in 2008/2009. There is currently no available information on construction programme and methodology, and its cumulative environmental impacts will be addressed by reasonable assumptions. However, it is advised that the construction work will potentially be entrusted to KCRC as a separate project subject to confirmation. A separate Environmental Permit (EP) will be applied from EPD for construction and operation of the roadworks. The Project Proponent would schedule the construction works and allow programme phasing to avoid major concurrent activities to be undertaken simultaneously in the vicinity. Construction of roadworks is likely to commence in late 2007 when all civil works of WKN and the nearest tunnel section are completed.

(8) Hong Kong Girl Guides Association Headquarter

· The proposed Hong Kong Girl Guides Association Headquarter is located at the junction of Jordon Road and Ferry Street. It is anticipated that the construction works will be undertaken concurrently with the construction of WKN and the northern tunnel of KSL from 2005 to 2007. There is currently no available information on construction programme and methodology, and its cumulative environmental impacts will be addressed by reasonable assumptions.

(9) Secondary School

· The proposed secondary school is located at the junction of Hoi Wang Road and Yau Cheung Road. The construction is scheduled to commence in 2007/08 and for completion by 2009/10. In accordance with the construction programme of KSL, all excavation works of the WKN northern tunnel for this section will be completed in September 2006, and the remaining works are only superstructure, backfilling and road reinstatement which will be completed by May 2007. Taking into account 2 months mobilisation period for the school project, the constructions are very unlikely to be concurrent with that of KSL.

(10) China Light Power Electricity Substation

· The China Light Power (CLP) electricity substation is planned at Lai Cheung Road. It is scheduled to be constructed in late 2004 for completion in 2007, and hence will overlap with the construction of northern tunnel of KSL. It is anticipated that most of the construction activities for this concurrent project would be superstructure works.

1.6 Structure of EIA Report

The structure of this EIA report is outlined below for easy reference:

Chapter	Title	Aims
1	Introduction	Introduces the background information and the layout of the EIA report
2	Study Scope	Outlines the objectives and scope for various environmental aspects
3	Selection of the Preferred Alignment	Summaries the options considered and presents the associated benefits and disbenefits
4	Construction Methodologies for the Selected Route Alignment	Summaries the construction programme and methodologies for the selected alignment option
5	Construction Dust Impact Assessment	Presents the legislation, methodology, assessment and recommendations for air quality impacts during construction phase
6	Airborne Noise Impact Assessment	Presents the legislation, methodology, assessment and recommendations for airborne noise impacts
7	Groundborne Noise Impact Assessment	Presents the legislation, methodology and assessment for groundborne noise impacts
8	Water Quality Impact Assessment	Presents the legislation, methodology, assessment and recommendations for water quality impacts
9	Waste Management Implications	Presents the legislation, methodology, assessment and recommendations for waste management
10	Land Contamination Assessment	Presents the legislation, methodology, assessment and recommendations for land contamination
11	Landscape and Visual Impact Assessment	Presents the legislation, methodology, assessment and recommendations for landscape and visual impacts
12	Cultural Heritage Impact Assessment	Presents the legislation, methodology, assessment and recommendations for cultural heritage
13	Hazard Assessment	Presents the legislation, methodology and requirements
14	Environmental Monitoring and Auditing Requirements	Presents the requirements for EM&A
15	Summary of Environmental Outcomes	Summarises environmental outcomes and benefits
16	Conclusions	Summarises the findings
17	References	Presents the relevant reference information

2. Study Scope

According to the Study Brief, the EIA should address the following:

· The considerations on alternative rail alignments, station designs and associated structures;

· The considerations on alternative tunnel construction methods, and the assumptions, uncertainties and risks implicit to each tunnel construction methods with respect to potential impacts on sensitive receivers during construction and operational phases;

· The considerations on the adverse effects due to the construction and operation of the proposed railway on the operational performance of the affected sensitive receivers including the Hong Kong Space Museum (HKSM) and the Hong Kong Cultural Centre (HKCC). The study will address the details of the construction programme, the construction methodologies, with an assessment of the extent to which the technologies to be employed are the best available proven technologies in order to avoid or mitigate potential adverse impacts to the maximum practicable extent;

· The construction and operational groundborne noise impacts on HKSM and HKCC;

· The potential airborne and dust impacts arising from the construction activities on the neighbouring sensitive receivers including residential units and schools;

· The operational noise impacts of the proposed ventilation shafts on the receivers;

· The potential cultural heritage impacts on the monuments and graded buildings including, but not limited to FMPHQ, KCR Terminus Clock Tower, Old Fire Station Buildings (OFSB), Peninsula Hotel;

· The potential impacts associated with the spoil generation and its transportation, stockpiling and disposal arrangements during the construction phase;

· The potential contamination impacts caused by the soil, marine deposit underneath the existing fill material during excavation works;

· The potential landscape and visual impacts of the construction activities, works area, ventilation shafts and other major structures above ground level, and also the impacts on the landscape elements including Champion trees and protected species;

· The cumulative environmental impacts caused by other concurrent projects;

· The environmental impacts of the Project including its alignment and ancillary infrastructures on the existing and planned uses and the likely environmental benefits of the rail.

3. Selection Of The PreFerRed Alignment

3.1 Alignment Options Considered

The alignment is divided into two main sections due north and south with respect to the proposed West Kowloon Station (WKN). The northern section runs almost parallel to the existing Airport Express Line leading to the WR NAC. It basically follows the alignment proposed in the Railway Development Strategy 2000 (RDS-2000) ^[3-1]. The alignment in this northern section runs in the narrow corridor between the existing Airport Express Line, West Kowloon Expressway and various planned developments in the vicinity. All these constraints prohibit any alternative corridors or even very minor deviations to the alignment proposed in the RDS-2000 Report.

The original southern portion of the RDS-2000 alignment assumed the implementation of the Kowloon Point Reclamation and the location of the Kowloon Point Station on the reclaimed land. However, as the Kowloon Point Reclamation will not be implemented, it is impossible to adopt the original RDS-2000 alignment. Alternative alignments have therefore been identified.

The developments along the southern portion of the alignment comprise of mainly high-rise buildings with piled foundations. Engineering constraints prevent any alignment options passing underneath these buildings to minimise impacts thereon (refer to the following sections and Figures 3-3 to 3-5). Accordingly, alternative alignments that follow the existing main road corridors were developed since they would have minimal impact on the neighbouring buildings. The following 4 alignment options have therefore been investigated (Figure 3-1).

A summary of the alignment options is given below:

Table 3-1 : Alignment options

Alignment Option	Description	Inland	Seaward	Remarks
1	Canton Road Scheme	Yes		Figures 3-2-1 to 3-2-3
2	Kowloon Park Drive Scheme	Yes		Figures 3-3-1 to 3-3-3
3	Kowloon Point Scheme (Note 1)		Yes	Figures 3-4-1 to 3-4-3
4	Harbour City Scheme		Yes	Figures 3-5–1 to 3-5-3

Note 1 The original alignment in the RDS-2000 followed Middle Road instead of Salisbury Road. Further study of the Middle Road option in the ER Extension between TST and Hung Hom [ref. East Rail - Extension - Hung Hom To Tsim Sha Tsui – EIA, EIA-036/1999] revealed that a section of Signal Hill would need to be removed for construction of the ETS station. As such, the Project Proponent adopted the Salisbury Road option and subsequently EIA report was approved under the EIAO in 2000.

3.1.1 Alignment Option 1: The Canton Road Scheme

Commencing from East Tsim Sha Tsui Station (ETS) the route runs westwards along Salisbury Road, and then turns northwards with a tight radius curve underneath the site of the FMPHQ into the Canton Road corridor (Figures 3-2-1 to 3-2-3).

The Canton Road Station (CAR) originally proposed in the EIA Study Brief was approximately centred on the junction of Canton Road and Haiphong Road. The tunnels then pass beneath the Kowloon Park Drive Flyover and then turn to the northwest at the TST Fire Station into the West Kowloon reclamation area. However, the CAR has been deferred and there is currently no programme for its implementation. Any additional future station would require an environmental permit to be applied separately under the EIAO.

3.1.2 Alignment Option 2 : The Kowloon Park Drive Scheme

The Kowloon Park Drive Scheme is another inland route option roughly parallel to the Canton Road Scheme. This alignment takes the same route as the Canton Road alignment along Salisbury Road, then takes a very tight radius curve beneath the YMCA Building into Kowloon Park Drive (Figures 3-3-1 to 3-3-3).

The proposed Kowloon Park Station would be situated partly below the existing Haiphong Road Temporary Market and partly under Kowloon Park and the Kowloon Park Drive Children’s Playground (KPDCP). At the north of Kowloon Park Station the approach tunnels avoid Kowloon Park Drive Flyover by being routed under Kowloon Park before turning northwest into the West Kowloon reclamation area at the TST Fire Station.

3.1.3 Alignment Option 3 : The Kowloon Point Scheme

The Kowloon Point Scheme is based on the route proposed in the RDS-2000. However, the scheme has been modified to suit the current location of the ETS with alignment along Salisbury Road instead of running beneath Middle Road and under Ocean Centre (Figures 3-4-1 to 3-4-3).

Again, following the same route as the Canton Road alignment along Salisbury Road, the tunnels descend at maximum gradient after passing over the MTR Tsuen Wan Line tunnels before entering the harbour near the Star Ferry Piers. The tunnel section in the harbour would probably involve immersed tube construction beneath the seabed.

The proposed Kowloon Point Station would be located in the Kowloon Point Reclamation. At the north of the site for Kowloon Point Station the alignment runs due north before connecting with the West Kowloon Reclamation and WKN. However, the Kowloon Point Reclamation which is required for the construction of Kowloon Point Station, will not be implemented.

3.1.4 Alignment Option 4: The Harbour City Scheme

The alignment runs along Salisbury Road and then turns with a tight curve underneath Star House and the Marco Polo Hong Kong Hotel, continuing northwards adjacent to the Harbour City seawall (Figures 3-5-1 to 3-5-3).

The proposed Harbour City Station would be located adjacent and parallel to the existing seawall outside the Gateway commercial tower blocks. At the north of Harbour City Station, the alignment continues alongside the China Hong Kong City into the West Kowloon Reclamation and then to WKN.

3.2 Selection of the Preferred Alignment

3.2.1 Reasoning for Choosing the Preferred Alignment

The 4 alignment options were evaluated on the basis of the critical factors that dictated the route selection process ^[3-2] which include:

Engineering Factors :	· Resumption of buildings · Accessibility and connectivity · Reclamation
Environmental Factors :	· Landscape resources · Construction noise and dust · Visual impacts · Heritage buildings · Waste generation · Groundborne noise & vibration · Impacts on parks · Ecology and water quality
Other Factors :	· Disruption to harbour activities · Commercial and cultural activities

3.2.1.1 Resumption of Buildings

The resumption requirements for the 4 alignment options are summarised in Table 3-2 below.

Table 3-2: Resumption requirements

Alignment Option	Description	Resumption requirements
1	Canton Road Scheme	· Not required
2	Kowloon Park Drive Scheme	· YMCA Building · Fuk Tak Koo Temple
3	Kowloon Point Scheme	· Not required
4	Harbour City Scheme	· Star House · Marco Polo Hong Kong Hotel (unless underpinning can be achieved with a deeper rail alignment)

Careful design and planning of the Canton Road Scheme has eliminated the need for temporary possession of the Haiphong Road Temporary Market during construction period and thus avoid any impact on Fuk Tak Koo Temple (see Chapter 4). Both Canton Road and Kowloon Point Schemes therefore do not require resumption of private buildings.

Unlike the Canton Road and Kowloon Point Schemes, the Kowloon Park Drive and Harbour City Schemes would require resumption of buildings. The piled foundations of the buildings have imposed constraints on the alignment of the railway in such a way that unless the buildings are resumed, a feasible alignment beneath the buildings is not possible. Specific for Kowloon Park Drive Scheme, it would likely require temporary or permanent possession of the Haiphong Road Temporary Market and resumption of the Fuk Tak Koo Temple, in addition to the YMCA Building, which is a recently renovated hostel providing accommodation (about 360 rooms) for tourists in the TST area.

Similarly, the Harbour City Scheme would require resumption of Star House and Marco Polo Hong Kong Hotel. Star House is a commercial building owned by multiple owners. Its plot ratio is near to the permissible limit and hence there is little incentive for redevelopment. Marco Polo Hong Kong Hotel is a well-established hotel located next to Ocean Terminal providing over 600 rooms and suites for accommodation. Although underpinning for the Marco Polo HK Hotel is feasible, a strata resumption would be required which will severely constrain the flexibility for redevelopment on this lot.

The YMCA Building, Star House and the Marco Polo Hong Kong Hotels are located within the business area of TST which is one of the locations favoured by tourists. These guestrooms and commercial buildings have great significance for the tourism industry. The lead-time for resumption of these private buildings is anticipated to be long, given the likelihood of objections from the tenants and the landlords. This obviously imposes an implicit programming risk which would critically impact the construction programme and the subsequent project completion date. As such, it is desirable to avoid such a risk as far as practicable. Kowloon Park Drive and Harbour City Schemes are therefore comparably less practicable to Canton Road and Kowloon Point Schemes in this respect.

3.2.1.2 Accessibility and Connectivity

Latest design for Canton Road Scheme (see Chapter 4) has included only one station at West Kowloon with a design provision for future CAR. In order to provide a meaningful comparison of accessibility and connectivity with the other three schemes of two stations, the deferred
CAR for Canton Road Scheme has been included in the evaluation. Any future incorporation of a station at Canton Road shall require consideration of material change to a designated project.

Both the Canton Road and Kowloon Park Drive Schemes are strategically located between Nathan Road and Canton Road which are the key business areas in TST. Passengers will be greatly benefited by the good accessibility of these two schemes.

However, there can be no connection to the proposed Kowloon Point Station under the Kowloon Point Scheme until completion of the Kowloon Point Reclamation, which will not be implemented in future. It is therefore not possible to proceed with the Kowloon Point Scheme (including the Kowloon Point Station) at this time. If the Kowloon Point Scheme were to be built without the Kowloon Point Station, the entire railway will not be able to serve the large patronage anticipated from the commercial activities along Canton Road. This option is therefore not desirable from a transport planning perspective.

The Harbour City scheme will require the Harbour City Station to be placed parallel to the seawall. Accessibility to the Harbour City Station would not be favourable by the passengers from the areas between Nathan Road and Canton Road. The Harbour City Station will also be approximately 200m further away from the MTR TST Station as compared to the Kowloon Park Station for the Kowloon Park Drive Scheme.

A summary of the accessibility and connectivity issues is given in Table 3-3.

Table 3-3 : Issues relating to accessibility & connectivity

Alignment Option	Description	Issues
1	Canton Road Scheme	· Good accessibility & connectivity [1]
2	Kowloon Park Drive Scheme	· Good accessibility & connectivity · Kowloon Park Station can be linked to MTR TST Station
3	Kowloon Point Scheme	· No access to Kowloon Point Station at this time · Not favourable in terms of accessibility and connectivity
4	Harbour City Scheme	· Not favourable in terms of accessibility and connectivity

Note:

[1] Good when assuming there is the CAR station.

Nonetheless, since CAR is deferred at this stage, the Canton Road Scheme is comparably less attractive than Kowloon Park Drive Scheme in consideration of accessibility & connectivity.

3.2.1.3 Reclamation

It has been assumed in the Kowloon Point Scheme that reclamation in Kowloon Point would be implemented. This is however inconsistent with the general principle of the “Protection of Harbour Ordinance” that stipulates the presumption against reclamation works unless with overriding public need, and encourages protection and preservation of the harbour as a special public asset and a natural heritage of Hong Kong.

According to the Court of Final Appeal judgement, the presumption against reclamation under the Protection of Harbour Ordinance can only be rebutted by establishing an overriding public need for reclamation, with public needs being the community needs including economic, environmental and social needs. In addition, the Government has announced that there will be no more reclamation other than South East Kowloon Development, Central Reclamation Phase III and Wanchai Reclamation Phase II. As such, the Kowloon Point Scheme is not preferred as compared to the Canton Road and Kowloon Park Schemes.

3.2.2 Environmental Factors

3.2.2.1 Landscape Resources

Trees in the KPDCP would be affected by the Kowloon Park Drive Scheme. It is also likely to encroach into Kowloon Park during construction and therefore may also affect some of the trees (including the Champion trees along Haiphong Road) and plantation in the park.

Possession of KPDCP is not required for Canton Road (except for a relatively small open space at the junction of Canton Road and Kowloon Park Drive), Kowloon Point and Harbour City schemes, and hence would have no impacts on the Champion trees along Haiphong Road. For Canton Road Scheme in particular, the original Haiphong Road subway has been shelved (see S1.3.1) and hence the impacts on Champion trees along Haiphong Road have been avoided. There would be however relatively minor potential impacts on trees along Salisbury Road and West Kowloon which are less sensitive areas as compared to the KPDCP. Besides, the construction of an emergency egress point in front of the existing retaining wall for the FMPHQ under the gazettal for the current Canton Road Scheme does not require any modifications to the wall and will therefore have no impact on these landscape resources. In short, Kowloon Park Drive Scheme is less favourable in this respect.

3.2.2.2 Construction Noise and Dust

All of the schemes would have similar alignments along Salisbury Road and hence the construction noise and fugitive dust impacts on the neighbouring area would be similar. Both the Kowloon Point and Harbour City Schemes are located further away from residential units along Canton Road that are sensitive to construction noise and dust. The alignment of the Kowloon Point Scheme would however be much closer to the existing residential development atop the AEL Kowloon Station. These residential buildings are sensitive to both construction noise and fugitive dust.

The current design of the Canton Road Scheme will adopt bored tunnelling method (ie using a tunnel boring machine, see Chapter 4). By using bored tunnelling, a more environmental friendly method, most of the construction activities will be conducted underground except some construction plant items near to the mucking out locations. This will minimise the construction noise and dust impacts on the sensitive uses along Canton Road to the maximum practicable extent during the construction period.

The construction phase environmental impacts caused by Kowloon Park Drive Scheme would be similar to Canton Road Scheme if bored tunnelling could also be adopted. However, if there are other constraints that dictate the use of cut-&-cover construction techniques, it is anticipated that the associated environmental impacts would be higher, especially for the residential units in Hankow Centre along Ashley Road.

3.2.2.3 Visual Impacts

All of the alignment options would have similar temporary visual impacts during construction phase on the section along Salisbury Road, which is one of the strategic locations for tourists and cultural events.

The Canton Road Scheme will have no visual impacts during construction of the tunnels along Canton Road (also a popular spot for tourists) by adopting bored tunnelling, except at locations near to the launching shaft and recovery shaft (please refer the location to Figure 4-1-1). Similar to construction noise and dust as described in S3.2.2.2, the construction phase visual impacts caused by Kowloon Park Drive Scheme would be similar to Canton Road Scheme if bored tunnelling could also be adopted. However, if there are other constraints that dictate the use of cut-&-cover construction techniques, it is anticipated that the associated visual impacts would be higher, especially for the residential units in Hankow Centre along Ashley Road.

Both the Kowloon Point and Harbour City Schemes would require reclamation and dredging in the harbour which is an important visual asset for people in Hong Kong and tourists. These reclamation works and dredging would inevitably require construction vessels to operate within the harbour. This would then have impacts on the attractiveness and visual appeal of the harbour as a result of the marine based construction activities. Hence, the Kowloon Point and Harbour City Scheme are not preferred in this respect.

During the operational phase, the Canton Road, Kowloon Point and Harbour City Schemes would have similar degree of impacts caused by above ground structures including plant buildings, station entrance, etc. As the Kowloon Park Drive Scheme would likely affect the Champion trees along Haiphong Road (see S3.2.2.1) and the Kowloon Park (see S3.2.2.7), it is anticipated that the associated visual impacts would be higher than other schemes. Hence, Kowloon Park Drive is less preferred in this respect.

3.2.2.4 Heritage Buildings

The status of key heritage buildings within the study areas for the 4 alignment options is identified in Table 3-4 below.

Table 3-4 : Status of heritage buildings

Heritage Resources	Status
FMPHQ (including old fire station accommodation block)	Declared monument
Former Kowloon-Canton Railway Clock Tower	Declared monument
Peninsula Hotel	Historical building (not yet graded)
Whitfield Barracks (Blocks S4, 58, S61 and S62)	Grade III buildings
Old Fire Station Main Hall	Grade III buildings
Kowloon West II Battery of the Former Whitfield Barracks	Grade I buildings
Saint Andrew’s Church	Grade II building

Direct impact on the heritage buildings: KCR Clock Tower, Peninsula Hotel, Whitfield Barracks, and Kowloon West II Battery can be avoided from all alignment options.

The Canton Road Scheme will however run underneath the Old Fire Station Buildings (OFSB) on the FMPHQ site which is being redeveloped. A vertical clearance of 6 – 16m will be maintained between these buildings and the top of KSL tunnels to minimise any impacts. The construction methodology (ie mined tunnelling in Chapter 4) will avoid physical contact with the OFSB, and hence the OFSB will be kept intact during the construction period (see Chapter 4).

3.2.2.5 Waste Generation

The Kowloon Point Scheme and Harbour City Scheme would inevitably require dredging of marine sediment around the harbour area. Depending on the level of contamination, the sediment would need to be disposed of either in open sea or in confined mud pits. It is unlikely that these dredged sediments can be re-used in this or other construction projects. On this basis, the Kowloon Point Scheme and Harbour City Scheme are less preferred when compared to the Canton Road and Kowloon Park Drive Schemes.

The bulk volume of excavated material requiring disposal for the Canton Road Scheme (using bored tunnelling) is up to approximately 0.99 M m³ (see Chapter 9) while the Kowloon Park Drive Scheme would generate about 1.4M m³, including the waste from the demolition of YMCA Building. The total volume of waste generated from the Kowloon Park Drive Scheme would be about 40% higher than that of the Canton Road Scheme. Hence, Canton Road Scheme is preferred when compared to the Kowloon Park Drive Scheme.

3.2.2.6 Groundborne Noise & Vibration

The Kowloon Park Drive Scheme tunnels would need to negotiate a very tight curve of 180m near the junction between Salisbury Road and Kowloon Park Drive. Such a tight curve is far below the acceptable design limit and would have impact on the line capacity. On the other hand, the curvatures for other Schemes would satisfy the acceptable design limit and hence would not affect the line capacity.

Moreover, from operational viewpoint, the tight curvature for Kowloon Park Drive Scheme will increase the unbalanced force of the wheel-rail interaction and give rise to serious noise and vibration problems at the most sensitive area near HKCC and HKSM. Passenger comfort will also be compromised due to lateral vibration instability of the train. Frequent maintenance (due to rapid abrasion of tracks and wheels) and high energy consumption will also impact the services.

Details of the operational groundborne noise impacts on the FMPHQ and other sensitive receivers (including hotels, schools and residential buildings) for the Canton Road Scheme are given in Chapter 7. The operational groundborne noise assessment has demonstrated that, by using special trackform, all the statutory requirements for operational groundborne noise impacts for the Canton Road Scheme could be met. Since the curvature of the Harbour City Scheme and Kowloon Point Scheme are less than Canton Road Scheme, it is anticipated any groundborne noise issues could also be resolved in a similar approach. Hence, there would be no preference on Canton Road Scheme, Kowloon Point Scheme and Harbour City Scheme from groundborne noise & vibration perspective.

3.2.2.7 Impacts on Parks

All four alignments would affect Nam Cheong Park to the same extent. No other parks or children playgrounds will be encroached or affected by Kowloon Point and Harbour City Schemes.

The Canton Road Scheme would affect a relatively small open space at the junction of Canton Road and Kowloon Park Drive, which forms part of the Kowloon Park Drive Children’s Playground.

The Kowloon Park Drive Scheme will need temporary possession of the KPDCP and, inevitably, a certain portion of the Kowloon Park near the ex-Museum of History, which is a very popular leisure area for not just the local residents but also the general public of Hong Kong. Kowloon Park Drive Scheme is therefore less desirable than the other three schemes in this respect.

3.2.2.8 Ecology and Water Quality

All the 4 alignment options would run along urban areas and there are no land based ecological sensitive areas in the vicinity. Tree felling will be avoided as far as practicable for all alignment options. Any trees that need to be felled/transplanted will require separate approval from relevant government departments.

For Kowloon Point and Harbour City Schemes which inevitably require dredging in the harbour, any suspended solids generated from the dredging activities will cause certain water quality impacts. Hence, the Canton Road and Kowloon Park Drive Schemes are preferred in this respect.

3.2.3 Other Factors

3.2.3.1 Disruption to Harbour Activities

Both the Kowloon Point and Harbour City Schemes would inevitably require construction activities in the harbour area directly in front of Harbour City and Star Ferry. This area is one of the busiest marine areas in HK and has both domestic and cross boundary ferry terminals.

Construction of the Kowloon Point Scheme would make use of the immersed tube method as well as requiring the underpinning of Ocean Terminal. Both construction methods are likely to disrupt this harbour area. It would also have adverse impacts on the operation of the Star Ferry which is one of the busiest locations for cross harbour commuting between Hong Kong Island and Kowloon Peninsula. It would also require extensive underpinning of Ocean Terminal and hence shipping operations at Ocean Terminal would be severely disrupted. Reprovision of the terminal deck and underpinning would create unacceptable disruption to the operations of these premises.

The Harbour City Station for the Harbour City Scheme will require protection for ship collision and hence substantial marine fenders would be necessary west of the station box. This would likely reduce the fairway areas. In addition, the station would require significant underpinning of or shortening / alteration to the existing piers. The existing seawater cooling pump house serving Harbour City Station would also require re-provisioning. Disruption to harbour activities in the vicinity would be inevitable.

Canton Road and Kowloon Park Drive Schemes are in-land routes and therefore would not involve any marine or dredging work and thus would avoid any disruption to the harbour activities.

3.2.3.2 Commercial and Cultural Activities

All of the 4 alignment options would inevitably affect the operation of several commercial and cultural premises alongside the alignments. These premises include performance venues, hotels and retails as summarised in Table 3-5 below:

Table 3-5 : Commercial premises and cultural venues that could possibly be affected

Alignment Option	Description	Issues
1	Canton Road Scheme	· Hotels along Salisbury Road and Canton Road · HKCC & HKSM
2	Kowloon Park Drive Scheme	· Hotels along Salisbury Road and Kowloon Park Drive · HKCC & HKSM & ex-Museum of History (to be re-opened as the Hong Kong Heritage Resource Centre) · Retail areas along Kowloon Park Drive
3	Kowloon Point Scheme	· Hotels along Salisbury Road · HKCC ^[1] & HKSM · Retail areas in Star House
4	Harbour City Scheme	· Hotels along Salisbury Road & Canton Road · HKCC ^[1] & HKSM

Note:

[1] The alignment in this option(s) is closer to the venues of the HKCC

The separation distances between alignment and HKSM for the 4 schemes are similar. However, the alignments of Kowloon Point and Harbour City Schemes would be closer to the HKCC than the Canton Road and Kowloon Park Drive Schemes. While the Kowloon Park Drive Scheme would be further away from HKCC as compared to the Canton Road Scheme, it would inevitably affect the ex-Museum of History (to be opened as the Hong Kong Heritage Resource Centre in late 2004) in Kowloon Park. The Canton Road Scheme would not affect the ex-Museum of History.

It is anticipated that careful planning and measures would be required to minimise disruptions on the operations (e.g. accessibility, loading / unloading etc) of these commercial premises and cultural venues. With the CAR for the Canton Road Scheme deferred and bored tunnelling along Canton Road adopted, disruption to the commercial premises alongside Canton Road are minimised as far as practicable.

3.2.4 Summary of Reasoning for Route Selection

A summary of the reasoning that has been considered during the route selection process is given below.

Table 3-6 : Summary of reasoning for route alignment selection

	Route Alignment Options
Criteria	#1: Canton Road Scheme	#2: Kowloon Park Drive Scheme	#3: Kowloon Point Scheme	#4: Harbour City Scheme
Engineering Factors
Resumption of Buildings	· Resumption of private buildings not required	· Resumption of YMCA Building (Not feasible) · Resumption of Fuk Tak Koo Temple	· Not required	· Resumption of Star House & Marco Polo HK Hotel (Not feasible)
Accessibility & Connectivity	· Less attractive with CAR deferred · Good with CAR in place	· Good	· Not desirable · No connection to Kowloon Point Station	· Not desirable
Reclamation	· Not required	· Not required	· Required (reclamation will not be implemented since it is inconsistent with the Protection of Harbour Ordinance)	· Not required
Environmental Factors
Landscape resources	· Less impact · No impacts on champion trees	· Higher impact · Champion trees may be affected	· Less impact · No impacts on champion trees	· Less impact · No impacts on champion trees
Construction noise and dust	· Minimal impact, use of bored tunnelling along Canton Road will minimize the construction noise and dust impacts, and other disruptions to the commercial premises.	· High impact if cut-&-cover needs to be adopted · Similar impacts as Canton Road Scheme if bored tunnelling is adopted	· Minimal impact (but acceptable with mitigation measures)	· Minimal impact (but acceptable with mitigation measures)
Visual impacts	· Minimal impact, use of bored tunnelling along Canton Road will minimize the visual.	· High impact if cut-&-cover needs to be adopted · Similar impacts as Canton Road Scheme if bored tunnelling is adopted	· Construction vessels will affect the attractiveness and visual appeal of the harbour	· Construction vessels will affect the attractiveness and visual appeal of the harbour
Heritage Buildings	· FMPHQ and OFSB protected by no contact construction methodology	· No impact	· No impact	· No impact
Waste generation	· No polluted sediment generation · Use of bored tunnelling can minimize the amount of excavated materials	· More excavated materials	· Potential release of polluted marine sediment	· Potential release of polluted marine sediment
Groundborne Noise & Vibration	· Operational noise & vibration can be mitigated · Train service & passenger comfort not compromised	· Unacceptable impact on the line capacity due to tight curvature of the track near the junction between Salisbury Road and Kowloon Park Drive; · More severe operational noise and vibration problems · Train services & passenger comfort compromised	· Operational noise & vibration can be mitigated · Train service & passenger comfort not compromised	· Operational noise & vibration can be mitigated · Train service & passenger comfort not compromised
Impacts on parks	· No impact on Kowloon Park · Encroach onto a relatively small open space at junction of Canton Road and Kowloon Park Drive	· Higher impact · Temporary possession of KPDCP · Encroachment into Kowloon Park	· No impact on KPDCP & Kowloon Park	· No impact on KPDCP & Kowloon Park
Ecology & Water Quality	· No ecological impact · No water quality impact	· No ecological impact · No water quality impact	· No terrestrial ecological impact · Dredging will affect water quality	· No terrestrial ecological impact · Dredging will affect water quality
Other Factors
Disruption to harbour activities	· No impact	· No impact	· Affect harbour activities · Affect Star Ferry	· Affect harbour activities
Commercial & Cultural Activities	· Disruptions to commercial premises along Canton Road will be minimized by using bored tunnelling	· Several hotels affected · Alignment furthest away from HKCC · Ex-Museum of History would be affected	· Several hotels affected but alignment closer to the HKCC	· Several hotels affected but alignment closer to the HKCC

3.3 Conclusion

Four route alignment options were evaluated during the route selection process. A summary of the reasoning that has been considered in the route selection process is presented.

3.3.1 Overall Summary for the Four Alignment Schemes Considered

3.3.1.1 Kowloon Point and Harbour City Schemes (ie the Sea-based Alignments)

Both of these routes raise significant issues of constructability and disruption. The Harbour City Scheme is least attractive given the significant disruption to Ocean Centre, Ocean Terminal, the associated piers and the requirement for resumption of Star House and Marco Polo Hong Kong Hotel.

Kowloon Point Scheme whilst technically possible would involve large scale underpinning of Ocean Terminal and unacceptable disruption to the operations of commercial premises (including Star Ferry). Re-provisioning of the Terminal will cause adverse effect on the harbour activities.

Both of these options are not viable given the current engineering constraints with regard to disruption/resumption of buildings and ferry, protection of the harbour and the likelihood that Kowloon Point Reclamation will not proceed in the near future. These engineering constraints would in turn impose a relatively higher cost than the land based alignment options.

The dredging activities associated with these sea-based alignments will cause adverse water quality impact. Kowloon Point Scheme involves reclamation works which are also not consistent with the general principle of the “Protection of Harbour Ordinance” that stipulates the presumption against reclamation works unless with overriding public need, and encourages protection and preservation of the harbour as a special asset and a natural heritage of Hong Kong. These sea-based alignments are therefore not recommended.

3.3.1.2 Canton Road and Kowloon Park Drive Scheme (ie Land Based Alignments)

The Kowloon Park Drive Scheme is less favourable since it requires resumption of the YMCA building. The tight curvature of the track near the junction between Salisbury Road and Kowloon Park Drive will also impose unacceptable impact on the line capacity and cause higher train induced groundborne noise and vibration impacts on the HKCC. This scheme would also encroach into Kowloon Park and the KPDCP and hence some of the champion trees along Haiphong Road would inevitably be affected.

Latest engineering design of the Canton Road Scheme has confirmed the feasibility of adopting bored tunnelling along Canton Road without the need for resumption of private buildings. As most of the construction activities for the tunnels along Canton Road would be conducted underground, impacts from construction noise, fugitive dust, visual and disruption to the retails alongside Canton Road would be minimised during the construction phase. All the champion trees along Haiphong Roads would be kept intact and there is no requirement for temporary dismantling of the OFSB for construction. Canton Road Scheme is therefore considered to be the preferred option.

3.3.2 Summary of Environmental Justifications for the Preferred Alignment Option

Landscape	· The Canton Road Scheme would not encroach onto the Kowloon Park which is an important landscape and leisure asset for the local residents.
Champion trees	· The Canton Road Scheme can avoid impacts on the Champion trees along Haiphong Roads. All the Champion trees will be kept intact during both the construction and operational stages. It is better than the Kowloon Park Drive Scheme which would inevitably affect the trees along Haiphong Road, and the Kowloon Park.
Visual impacts	· Bored tunnelling will be adopted along Canton Road for the Canton Road Scheme. Most of the construction works will be conducted underground except at the mucking out locations. The visual impacts have therefore been minimised as far as practicable by using a more environmental friendly construction method. · Since the Canton Road Scheme does not require any marine works, the attractiveness and appeals of the harbour can therefore be preserved.
Construction noise & dust	· Similar to visual impacts, the use of bored tunnelling will minimise the construction noise and dust impacts as far as practicable.
Waste generation	· The Canton Road Scheme will generate less C&D materials and create no polluted marine sediment. · Due to the need for resumption of the YMCA building, the C&D waste generated from Kowloon Park Drive Scheme would be more than the Canton Road Scheme.
Ecology & water quality	· Unlike the Kowloon Point and Harbour City Schemes, the Canton Road Scheme does not require dredging of marine sediment in the Victoria Harbour. Hence, it would be much more environmental friendly in terms of marine ecology and water quality.

After reviewing all the environmental justifications, it is apparent that the Canton Road Scheme presents the most environmental friendly route put forwards for EIA study of this project.

4. Construction Methodologies for the Selected Route Alignment

This section outlines the details of the construction methodologies for the selected route alignment along Canton Road corridor (see Chapter 3). The environmental benefits and disbenefits of the construction methodologies considered are also presented.

4.1 Overview

4.1.1 Alignment

The KSL will complete the rail link between WR NAC Station and ER ETS Station (Figures 4-1-1 to 4-1-3). The alignment commences from ETS Station along Salisbury Road and enters the Canton Road corridor under the FMPHQ. It is heavily constrained both vertically and horizontally by existing buildings including HKCC, YMCA, and No 1 Peking Road, and the underground structures such as subways, MTR tunnels and highway bridge foundations, and also many utilities including drainage.

After the Canton Road corridor, the alignment runs due north to the WKN. It then passes under the western corner of Man Wui Street, under Yau Ma Tei (YMT) Interchange, Cherry Street and finally joins the NAC overrun tunnel near the Prince Edward Roundabout. The alignment is also constrained by the narrow corridor between the existing Airport Express Line / Tung Chung Line, West Kowloon Expressway and various planned development in the vicinity.

Figures 4-1-1 to 4-1-3 and 4-2-1 to 4-2-2 show the proposed alignment, station location, station entrances and connections. Other than the above-grade portion of the station, entrances to the station and ventilation / plant buildings, and a short section of tunnel near Nam Cheong Park to interface with WR, the alignment and other ancillary facilities will be underground.

The location, level and approximate dimensions of the short interface tunnel section with WR are illustrated in Figure 4-3. Since this section has to interface with the existing WR, there are no alternative locations outside the Nam Cheong Park. The tunnel box will be covered with topsoil and provided with landscape elements and form an integral part of the Nam Cheong Park (see Chapter 11 for details).

4.1.2 Train Station

West Kowloon Station (WKN) will be located at West Kowloon on the west side of Canton Road between Austin Road and Jordan Road. The originally planned Canton Road Station (CAR) at Canton Road has been deferred and there is currently no implementation programme for this station. However, the track and tunnels are maintained horizontally for a length of 220m centred on Haiphong Road with sufficient vertical separation for the future construction of CAR. In case the CAR is confirmed in the future, it will constitute a separate EIA or variation of EP, and a separate approval under the EIAO is required.

4.1.3 Ventilation / Plant Buildings

The current design of the ventilation/plant building has avoided temporary possession of the KPDCP (except for a relatively small open space at the junction of Canton Road and Kowloon Park Drive) and the Haiphong Road Temporary Market by relocating the mechanical plant and other facilities to the WKN. Hence all the champion trees along Haiphong Road will not be affected. The current design has 2 ventilation / plant buildings for the KSL as follows:

· YMT ventilation / plant building located at Hoi Ting Road, and between YMT Interchange and Cherry Street (Figure 4-4); and

· Canton Road Plant Building (CRPB) at the junction of Kowloon Park Drive and Canton Road (Figure 4-5).

The selection of YMT ventilation building location was a result of agreement made with various government departments. Various locations were considered during the selection process. Location to the south of GI/C site is deemed not feasible due to future government developments. Areas near YMT Interchange are not feasible since it was reserved for the proposed Central Kowloon Route. In addition, there are no available lands for the ventilation building north of the proposed site.

The current location of YMT ventilation building is optimised such that it is halfway between Nam Cheong Station and West Kowloon Station and the emergency assembly point (EAP) is also located within the ventilation building thus minimising further land intake.

The ventilation shafts for WKN will be located at the two ends of the station (Figures 4-2-1 and 4-2-2). Necessary plant items will be accommodated in the ventilation / plant buildings, including transformers, water-cooled chillers, air compressors, water meters, gas cylinders, telecom, battery etc.

The latest scheme designs of the ventilation shafts have been incorporated in this EIA for visual impact assessment (see Chapter 11). Details (e.g. orientation) of the ventilation shafts will be further developed by the Design-&-Built Contractor. Assessment of noise impact from the ventilation building / shafts have taken account of all four different orientations and recommendation for corresponding maximum allowable sound power levels have been made.

4.1.4 Cooling Facility

Alternatives to conventional air-cooled system have been considered in order to increase operation energy efficiency. Both seawater and freshwater cooling systems have been studied.

Seawater cooling plant is typically 20-25% more energy efficient than conventional air-cooled system. However, the use of seawater cooling requires a pumping station and associated pipework within the WKCD site. Since the WKCD development is still in the tendering period, imposing a seawater cooling facility within the WKCD site would pose severe design constraints on the development and planning of WKCD and hence would not be acceptable. Fresh water-cooling plant is approximately 50% more energy efficient than conventional air-cooled system. Plant space occupied by the fresh water-cooling system is also much less than the conventional air-cooling system and can therefore be easily integrated within the WKN. In addition, the WKN location also falls within the zone of pilot scheme for freshwater cooling promoted by the Water Services Department (WSD). It is therefore natural to adopt freshwater cooling system the project.

The current design has allowed for a centralised fresh-water cooling facility located within the WKN to serve both the station and the tunnel (see Figure 4-2-1 for location and approximate dimensions). Provision is also made for expansion of capacity to cater for the future CAR. The nearest existing sensitive receivers are located at more than 150m away. Operational noise impact of this facility is given in S6.2.

4.2 Construction Areas and Work Sites

4.2.1 Construction Areas

Preliminary engineering design has identified the locations of major construction areas along the alignment during the construction period (Figures 4-1-1 to 4-1-3). Some of the areas will be used as site offices, storage yards etc while others will be used for the construction of railway structures.

4.2.2 Key Construction Elments

A summary of the work sites and the key construction elements along the alignment is given in the Table 4-1 below and illustrated in Figures 4-1-1 to 4-1-3.

Table 4.1 : Summary of construction elements for individual worksites

Worksites		Description / Key Construction Elements
Ref	Location
1	Salisbury Road	· Tunnels under Salisbury Road · Reprovisioning of New World Subway No 1
2	FMPHQ	· Tunnels beneath the existing FMPHQ
3	Between WKN and Canton Road	· Tunnels under Canton Road · CRPB, the ventilation shafts · Emergency Egress Point and Construction Access Shaft
4	WKN	· WKN · Station entrances & associated facilities.
5	WKN to Cherry Street	· YMT ventilation building · Tunnel to the north of WKN up to Cherry Street · Local culvert diversion (for culverts JR, PS, WR and DS) at locations in conflicts with the tunnel alignment. · Footbridge FB14 modification
6	Cherry Street	· Tunnel section underneath Cherry Street · Underpinning of the foundations of Footbridges A & A1, & culverts
7	Between Cherry Street and WR NAC Station	· Underground tunnels ascending to the at-grade section near Nam Cheong.

4.3 Construction Methodologies

A number of construction methodologies have been considered for construction during the design process. These include:

· Cut-&-cover tunnelling;

· Bored tunnelling; and

· Mined tunnelling.

Appendix 4-1 presents a general description of these methodologies, the key work stages (e.g. install temporary walls / D-walls, grouting, install temporary traffic decks, excavation, tunnel construction and reinstatement), typical construction plant items involved, and the associated environmental benefits and disbenefits in terms of dust, noise, vibration, waste etc. The following sections describe the construction methods recommended for various worksites and their respective relevant construction issues.

4.3.1 Work Site 1 (Salisbury Road) (Figure 4-1-1)

4.3.1.1 Tunnels

Bored Tunnelling

Construction of this section by bored tunnelling has been considered during the design stage and concluded unlikely to be practicable due to various constraints including East Rail Extension, subways, existing MTR etc, as summarised below.

Table 4.2: Summary of constraints along Salisbury Road

Items	Engineering Constraints
East Rail	· The KSL must match with the level gradient and cant of the overrun tunnel at the end of the ER extension
New World Subway No 1 (Figure 4-7)	· The KSL has to pass under the existing subway
MTR Tsuen Wan Line tunnels and box culvert in Nathan Road (Figure 4-7)	· The KSL must pass over the MTR Tsuen Wan Line Tunnels and pass under the DSD box culvert which runs down Nathan Road
Kowloon Park Drive Pedestrian Subway	· The KSL must pass under the Kowloon Park Drive Pedestrian Subway
Railway vertical gradient	· 3% maximum

Minimum soil cover required for safe bored tunnelling operation will be equivalent to two tunnel diameters such that arching effect for safe bored tunnelling operation could be achieved in accordance with the approved EIA Report for the East Rail Extension, Hung Hom to Tsim Sha Tsui (ref EIA036/1999). The Worksite 1 is actually a continuation of the East Rail Extension along Salisbury Road and thus the minimum two diameter soil cover is also required in KSL.

The external diameter of each tunnel would be about 8.2m, which is designed for special trackform to protect the HKCC, HKSM and other premises along Salisbury Road (see Chapter 7) from operational groundborne noise. As such, the soil cover required would be at least 16m. However, due to the constraints described in the above table, the soil cover for most of the areas along Salisbury Road is less than 10m. It is therefore not feasible to adopt bored tunnelling along Salisbury Road.

Microtunnelling uses horizontal pipe piles to support the ground around the excavation. Launching and reception pits are required for drilling in the horizontal piles. These pits would need to be separated at approximately 30m. Hence, there would be approximately 6-7 launching and reception pits for construction of the tunnel section along Salisbury Road. These pits would result in significant disruption to the traffic. Thus, the microtunnelling technique would not have advantages over the cut-&-cover construction methodology. In addition, the construction period for using microtunnelling would also be 12 months longer than using the cut-&-cover methodology.

This prolonged construction period will unnecessarily increase the duration for which the locals and tourists will be affected by the environmental nuisance (including construction noise, fugitive dust, visual etc) caused by the construction works at the launching and reception pits. In addition, the commercial areas in the vicinity would be deprived of the immediate economic benefits from the early completion of the KSL.

The use of microtunnelling would have the benefit of generating less construction waste materials as compared to Cut-&-Cover tunnelling. However, since the difference in the amount of waste generated for the section along Salisbury Road would be relatively small as compared to the total amount of waste generated by the entire project, the overall benefits of reducing the waste by using microtunnelling at this worksite is not considered to be significant.

Mined Tunnelling

Mined tunnelling was also considered for construction of the tunnel section along Salisbury Road. However, it was ruled out due to the following reasons:

· Given the relatively shallow soil cover along Salisbury Road (especially for the interface section with ER ETS Station), there could be risk of collapse during mined tunnelling. Temporary traffic decks would be required to ensure safe movement of traffic above the tunnels whilst they are under construction. The construction of such a deck along Salisbury Road will negate the advantages that would otherwise be achieved from avoiding cut-&-cover tunnelling.

· In addition, there are a number of major utilities and services buried beneath Salisbury Road. These include private water mains to hotels in Tsim Sha Tsui; cooling mains supplying three of the MTR stations in Nathan Road; water, gas, and electricity supply to all the buildings in Salisbury Road; and sewerage and drainage serving much of the West side of the Kowloon peninsula. Damage to any of these would have major implications and would likely affect many very prominent properties in the area for extended period of time. Mined tunnelling beneath or grouting ground adjacent to these utilities and services will require extensive protection works including, to the worst case, exposing all these utilities and services to ensure that they are not damaged by drilling and the like. The process of exposing and protecting these services and utilities will negate the environmental advantages over cut-&-cover tunnelling.

· A cut-&-cover shaft in Salisbury Road would still be required for access and spoil removal and a longer construction period (approximately 4 months longer than cut-&-cover tunnel construction). This would result in extended disruption (e.g. traffic) along Salisbury Road. This prolonged construction period will unnecessarily increase the duration which the locals and tourists will be affected by the environmental nuisance (including construction noise, fugitive dust, visual etc) caused by the construction works at the construction access shaft.

· The use of mined tunnelling would have the benefit of generating less construction waste materials as compared to Cut-&-Cover tunnelling. However, since the difference in the amount of waste generated for the section along Salisbury Road would be relatively small as compared to the total amount of waste generated by the entire project, the overall benefits of reducing the waste by using mined tunnelling is not considered to be significant.

Cut-&-Cover

Cut-&-cover construction is therefore the only feasible option for constructing the Salisbury Road tunnels but mined tunnel will be incorporated for short sections where the constraints demand this method. Mucking-out areas will be located along Salisbury Road where temporary traffic diversions and road decking are required to maintain traffic flow during construction. There is no need for diversion of the trunk sewer underneath Salisbury Road.

4.3.1.2 Reprovision of New World Subway No 1

The existing New World Subway No 1 will be reprovisioned on a new alignment on a temporary basis before removal of part of the existing subway for construction of the railway tunnels (Figure 4-7).

4.3.2 Work Site 2 (FMPHQ) (Figure 4-1-1)

Construction of this section by bored tunnelling has been considered during the design stage but is not preferred because of the geometry of the railway tracks which have minimum radius curves and are converging. The railway alignment beneath the FMPHQ site is such that the proximity of the tracks would result in insufficient clearance between the tunnels if this section of the alignment was constructed by bored methods. This in combination with potential difficulties due to the low rock cover above the upper track makes the bored option not preferred.

From environmental perspective, the use of bored tunnelling underneath FMPHQ will require a retrieval shaft near to the junction of Salisbury and Kowloon Park Drive. Since this shaft has to be constructed by cut-&-cover method, using bored tunnelling underneath FMPHQ will not have significant environmental benefits since the tunnel along Salisbury needs to be constructed by cut-&-cover anyway. Cut-&-cover tunnelling in this work site is also considered not feasible as it would cause adverse impacts on the monuments including the FMPHQ building and the OFSB.

The use of chemical splitting or Penetrating Cone Fracture (PCF) system will require the use of hydraulic breakers to break the rock into manageable size before transporting out from the tunnel. Hence, it has no significant environmental benefits as compared to drill & blast. In addition, the use of chemical splitting or PCF system will require a longer construction period and hence extended disturbance from the mucking out locations.

Mined tunnelling (drill-and-blast) will therefore be adopted. The access shaft (see S4.3.3) will be located at the junction of Canton Road and Peking Road (A4 in Figure 4-1-1). A clear separation of about 6m between the tunnels and the OFSB, and 16m from the Main Building will be maintained. Neither resumption nor temporary dismantling of the OFSB is required.

4.3.3 Work Sites 3 (WKN to South of Canton Road) (Figure 4-1-1)

4.3.3.1 Tunnels

The use of cut-&-cover tunnelling will cause adverse impacts (including traffic, disruption, construction dust and noise etc) on the sensitive receivers and commercial premises along Canton Road and hence is not adopted for this section. Bored tunnelling, a more environmental friendly construction method, will therefore be adopted along Canton Road.

The geological nature (ie soft ground) of the Canton Road corridor requires ground treatment ahead of the TBM drives to stabilise the zone between the two tunnels and adjacent building foundations. The ground treatment will be working from north to south on two fronts down Canton Road, with one from WKN to CRPB (A5 in Figure 4-1-1) and the other from CRPB to the access shaft at south of Canton Road (A4 in Figure 4-1-1). Each section is approximately 400m long and will take approximately 2 months for each 50m sub-section. However, the detailed design will be conducted by the Design & Build Contactor at a later stage, and he would further review the need for ground treatment for the section along Canton Road, taking into account any specific construction methodology for the bored tunnelling.

Given that most of the construction activities for bored tunnelling will be conducted underground (except for ground treatment and construction of shafts), the associated construction noise and dust impacts caused will be much less than the conventional cut-&-cover method. Disruption to the retail business along Canton Road is not anticipated except some relatively minor and local disruption during ground treatment and construction of the shafts. A Construction Traffic Impact Assessment Report will be separately submitted to the relevant authorities for approval.

4.3.3.2 Launching Shaft

The shaft will be located at the southern end of WKN (Figure 4-1-1). Walls of the shaft will be constructed by D- walls or similar techniques. The TBM will be assembled inside the launching shaft and all tunnel linings will be delivered through this shaft. In order to meet the programme, the TBM will need to operate 24 hours a day. Traffic decks are not envisaged to be required during the construction period except for the small section underneath Road D12. However, a noise insulating cover will be installed for the launching shaft. After structural completion, the launching shaft will be backfilled or integrated with WKCD.

During daytime period, the conveyor at the launching shaft will transfer the spoil from the tunnel portal to neighbouring construction area A7 (about 20m long) (Figure 4-1-2), and then transported by lorries to the barging facility (A6 in Figure 4-1-2). The conveyor system will be used to lift up the spoil from the bottom of the launching shaft to the ground level only (about 20m tall). The feeding point is at the bottom of the launching shaft and the discharge point will be located at the grade level of Area A7. The feeding point and the discharge point will be connected by a conveyor belt driven by motors and gears. The whole system will be supported by steel structure. The tentative location of conveyor belt is indicated in Figure 4-1-2, but is still subject to the detailed design. However, it is anticipated that the conveyor belt system would have the following features as standard good practices:

· Conveyor system will be fully enclosed to suppress dust emission

· Conveyor transfer points and hopper discharge areas will be enclosed to control dust emission

· At the fixed transfer point, a three-sided roofed enclosure with a flexible curtain at the entrance point would be provided. Exhaust fans shall be provided for this enclosure and vented to a suitable fabric filter system.

During normal hours, the noise insulating cover at the launching shaft will be opened to facilitate tunnel construction. During restricted hours, the noise insulating cover will be closed in order to enclose all the noise generating plant items (e.g. diesel train, mortar car, TBM etc) inside the shaft and minimise the construction noise impacts on the neighbouring noise sensitive receivers (refer to Chapter 6).

Details of the noise assessments during daytime and restricted hours are given in Chapter 6. The need for a separate application of Construction Noise Permit (CNP) for works during restricted hours is also highlighted in Chapter 6.

4.3.3.3 Emergency Egress Point and Construction Access Shaft

The shaft (A4 in Figure 4-1-1) is located near the southern end of Canton Road at the junction with Peking Road. Cut-&-Cover method using pipe pile walls or similar techniques would be required for this shaft. Temporary traffic decks will be installed during the excavation and tunnel construction periods. Mucking out would be required for the construction of this shaft. An Emergency Egress Point (EEP) will also be located at the Construction Access Shaft (Figures 4-8 & 11-5-33). Most of the important retaining walls along the western boundary of the FMPHQ will be demolished as part of its redevelopment, according to the Project Profile of FMPHQ. The western boundary will be converted to different uses including E&M, commercial, entry etc. The historical tunnel to be preserved to the southern end of Canton Road is more than 100m away from the EEP. It is therefore anticipated that there will be no impacts of this structure on any historic retaining walls.

The location of the EEP is dictated by fire safety requirements (requiring either cross-passage for tunnels at maximum spacing of 240m or escape to ground level every 762m). Since cross passages cannot be provided for the tunnel section near the FMPHQ and south of Canton Road where stack arrangement is adopted, exits at ground level must be provided. Relocating the EEP to other locations will compromise the safety for the passengers. Alternative option of locating the EEP within the FMPHQ site would alleviate concerns with respect to a constraint to footpath widths, however, the current railway reserve stipulated in the lease conditions of FMPHQ has not covered the provision for an EEP within the FMPHQ site, it is considered that resumption of space within the FMPHQ site for the EEP might incur legal actions being taken against the Government by the developer. As such, this alternative site option for EEP was not recommended to be pursued. Since the EEP will be constructed by the cut-&-cover technique, in consideration of environmental performance of the various EEP locations, the construction noise, dust and visual impacts will be of similar extent.

4.3.3.4 Plant Building (A5 in Figure 4-1-1)

The CRPB (Figures 4-1-1 & 4-5) will be constructed using cut-&-cover with pipe pile walls, or similar techniques. Superstructure will be constructed by in-situ concreting. Temporary traffic decks will be installed during the excavation. Mucking out would be required for the construction of this plant building.

4.3.4 Work Site 4 (WKN) (Figure 4-1-2)

The station box of WKN (Figures 4-1-2, 4-2-1 & 4-2-2) will be constructed by cut-&-cover using D-wall or similar techniques. Sequenced construction and temporary decking will be necessary to maintain existing roads and footpaths across the excavated site. The construction would be approximately divided into three sections which will be progressed at a similar rate.

4.3.5 Work Site 5 (WKN to Cherry Street) (Figures 4-1-2 & 4-1-3)

4.3.5.1 Tunnels

The use of TBM as a method of construction for the tunnels between WKN and Cherry Street was assessed during the early stage and was ruled out for the following reasons;

· There is a requirement for a pocket track to the north of WKN for stabling disabled trains and this section cannot be constructed using a TBM. It reduces the length of possible tunnel between WKN and Cherry Street that could be constructed using TBM to approximately 800m.

· The need for diversion of the sewerage box culverts (JR, PS, DS & WR) to the north of pocket track supports the use of cut -&-cover method (Figure 4-9).

· There are also space constraints on the approach to and beneath Cherry Street, to the west adjacent to the MTRC Airport Express Line (AEL) and to the east adjacent to the Olympian City II development. The available width between these constraints would mean that TBM tunnels would be too close with a separation of significantly less than the minimum of one tunnel diameter width required. In addition, under the Cherry Street Culverts and Underpass, even closely spaced TBM tunnels would conflict with the AEL Station and Olympian City II foundations which would otherwise require extremely complex underpinning works. However, due to the constrained location, it is very difficult to underpin these structures, particularly for the footbridge foundation near Olympic Station as the foundation is situated between two narrowly spaced box culvert underneath Cherry Street. Nevertheless, the underpinning of the foundation cannot be avoided even if the spacing is narrowed to 0.5 TBM diameter. It is not recommended that the spacing of the TBM to be less than one diameter since the soil is basically reclamation sandfill, which is not ideal soil material for using TBM. In addition, the low cover of the four box culverts and Cherry Street Underpass to KSL tunnel will further impose difficulty to perform ground treatment. Therefore the TBM section would need to stop before reaching Cherry Street. Taking into account the length required to converge the alignment into a box section, the reception shaft would have to be located close to the Yau Ma Tei Ventilation Building (see S4.3.5.3). This reduces the length of possible bored tunnel further to 500m.

· As the length of possible TBM tunnel is within an area of largely reclaimed land, there is a high risk of obstructions (e.g. sea walls, abandoned sheet piles) along the tunnel length that would be difficult and time consuming to deal with.

· The duration for just the procurement of a TBM would be at least 13 months. In addition, there are only limited sensitive receivers around the 500m tunnel section. Thus, bored tunnel is not viable both from an economical and a programme point of view.

Therefore, it was concluded that TBM is not a viable solution due to all the constraints identified in the Cherry Street area. Cut-and-cover approach is recommended for this area. The tunnel will be constructed from both the southern and northern ends towards the middle, in relatively short sections (about 100m long). The installation of D-wall or other similar techniques will be commenced in the first sub-section. After finishing the D-wall construction, the plant items will be moved to the adjoining sub-section. At the same time, soil excavation and concreting will be commenced in the first sub-section. This arrangement will be repeated until all the sub-sections along the work site are completed. The spoil will be transported by lorries to the barging facility.

It should be noted that the KSL construction will be undertaken under Design-and-Build contracts and thus the Contractor is ultimately responsible for the temporary works depending on his past experience and available plant and resources.

4.3.5.2 Footbridges

Other construction works in this section include the modification of the Footbridge FB14 and the construction of a new footbridge (Figure 4-9). Temporary decking for traffic management will be provided to maintain existing roads and footpaths.

4.3.5.3 YMT Ventilation Building (Figure 4-4)

The YMT ventilation building will be constructed using cut-&-cover with D-wall or other similar techniques. Superstructure will be constructed by in-situ concreting.

4.3.6 Work Site 6 (Cherry Street Underpass) (Figure 4-1-3)

The use of bored tunnelling in this tunnel section is precluded due to the constraints imposed by the foundations of Footbridges A & A1 (connecting Olympic Station with both Olympic City II and HSBC Centre) and the limited options for effective underpinning of these piers. Open cut with a short section of mined tunnelling is therefore proposed for this short tunnel section (about 100m long). Figure 4-10 illustrates the location of these footbridges.

4.3.7 Work Site 7 (Between Cherry Street and WR NAC Station) (Figure 4-1-3)

The underground tunnel from Cherry Street will ascend to at-grade level to integrate with the WR overrun section to the south of NAC Station (Figures 4-1-3 & 4-3). Bored tunnelling is not practicable for this interface section because of insufficient soil cover (maximum 14m for this section). The relatively high gradient is also not favourable for bored tunnelling and hence cut-&-cover method is required.

4.4 Other Construction Issues

4.4.1 Construction Programme & Plant Inventory

The construction work will commence in early 2005 and is scheduled to be completed by late 2007. Testing and commissioning of the railway system will then be conducted for target completion for operation in late 2008 / early 2009. Most of the construction works will be undertaken in normal working hours to complete from 7:00 am to 7:00 pm, except the 24-hour TBM operation (see S4.3.3.1). The construction plant inventory for the entire KSL is given in Appendix 4-2. A tentative construction programme with the associated construction activities at each work site is given in Appendix 4-3.

The Contractor, when developing their own construction programme and methodology, shall take into account the design, work areas, scheme boundary, mitigation measures etc described in this EIA Report. The need and extent of the mitigation measures shall be updated by the Contractor and seek approval from the relevant authorities. If the Contractor wants to include more work areas which are not included in this EIA, he shall apply for a variation of EP under the EIAO.

4.4.2 Barging Facility

The current design is to have all the public fill materials transported by lorries to the barging facility. The barging facility will be located in West Kowloon reclamation area with two barge loading ramps. This facility will also be used for delivery of materials such as tunnel segments etc. The design of the facility will be similar to the one being used in the East Rail Extension Project in Hung Hom Bay, with the following features:

· All road surfaces within the barging facility will be paved.

· Dust enclosures will be provided along the loading ramps to avoid dust dispersion.

· Vehicles will be required to pass through designated wheel washing facilities before leaving the barging facility.

Chapters 5 & 6 address the secondary environmental impacts of this facility and recommend the required mitigation measures.

4.4.3 Stockpiles

In order to reduce the amount of spoil to be disposed, it is proposed that certain portion of the excavated spoil will be stockpiled (about 5m high) in various parts within the scheme boundary (Figures 4-1-1 to 4-1-3) for later reuse as backfilling (see Chapter 9 for the amount of reusing C&D material). Chapters 5 & 6 address the secondary environmental impacts of these temporary stockpiles and recommend the required mitigation measures.

4.4.4 Work Area in Shek Mun

There is another storage area located in Shek Mun in Shatin. This area is currently used by the MOS Rail construction and will be handed over to the KSL Contractor for general storage / office.

5. Construction Dust Impact Assessment

5.1 Legislation and Standards

The principal legislation for controlling air pollutants is the Air Pollution Control Ordinance (APCO) (Cap 311)^[5-1] and its subsidiary regulations, which define statutory Air Quality Objective (AQOs) for 7 common air pollutants. The AQOs for these air pollutants are tabulated in Table 5-1 below.

Table 5-1: Hong Kong Air Quality Objectives

Pollutant	Concentration in micrograms per cubic metre ^[1] (Parts per million, ppm in brackets)
	1 Hour ^[2]	8 Hour ^(3]	24 Hours ^[3]	3 Months ^[4]	1 Year ^[4]
Sulphur Dioxide	800 (0.3)		350 (0.13)		80 (0.03)
Total Suspended Particulates	500 ^[7]		260		80
Respirable Suspended Particulates ^[5]			180		55
Carbon Monoxide	30,000 (26.2)	10,000 (8.7)
Nitrogen Dioxide	300 (0.16)		150 (0.08)		80 (0.04)
Photochemical Oxidants (as ozone) ^[6]	240
Lead				1.5

Notes:

[1] Measured at 298K(25 ^oC) and 101.325 kPa (one atmosphere).

[2] Not to be exceeded more than three times per year.

[3] Not to be exceeded more than once per year.

[4] Arithmetic means.

[5] Respirable suspended particulates mean suspended particles in air with nominal aerodynamic diameter of 10 micrometres or smaller.

[6] Photochemical oxidants are determined by measurement of ozone only.

[7] Not an AQO. Suggested short term averaging level for 1 hour is 500 µg/m3. There is no exceedance allowance for 1-hour TSP guideline level.

For construction dust impact, reference shall also be made to the TM-EIA^[5-2]. An hourly averaged Total Suspended Particulates (TSP) concentration of 500 μg/m³ shall not be exceeded.

5.2 Air Sensitive Receivers

The landuses in the vicinity of the proposed alignment consist of commercial buildings, hotels, residential premises, educational institutions and open space. Site surveys have been carried out to identify Air Sensitive Receptors (ASRs) within 500m from the site boundary in accordance with TM-EIA ^[5-2] Annex 12 and Hong Kong Planning Standards and Guidelines (HKPSG) ^[5-3]. The worst affected ASRs during the construction phase of the proposed works have been considered.

A list of the key representative ASRs for construction dust assessment and their distances to the nearest worksites are provided in Figure 5-1. Their respective locations are illustrated in Figures 5-2-1 to 5-2-3. Currently there is no plan for topside developments on the WKN. Other sensitive uses within 500m from the site boundary include playgrounds, open space and urban parks etc.

5.3 Potential Sources and Emission Inventory

5.3.1 Potential Sources of Dust

The running tunnels will be constructed by cut-and-cover, bored tunnelling and mined tunnelling methods respectively at different sections and the WKN will be constructed by cut-&-cover method. Locations of worksites, access shaft, stockpiles and barging facility are illustrated in Figure 5-3.

Prior to any bulk excavation, temporary road decks will be installed along Salisbury Road, shaft areas and the tunnel section between Lin Cheung Road and Lai Cheung Road to maintain traffic flow during construction, and reduce the dust dispersion to the vicinity of the site. As most of the works for the bored tunnelling will be performed underground, dust will only be generated during excavation and reinstatement of the access shafts. Details of construction methodology are given in Chapter 4.

Specifically, construction dust will be potentially generated from the following activities:

· Soil excavation activities;

· Backfilling;

· Wind erosion;

· Temporary storage of spoil on site;

· Transportation / handling of spoil;

· Underground blasting activities; and

· Loading and unloading of excavated materials at barging facility.

Since excavation and backfilling activities will involve large quantities of earthworks and silty material handling, it is anticipated that there will be significant dust impact as a result of these activities if no appropriate mitigation measures are implemented. On the other hand, the drill-&- blast activities underneath the FMPHQ will be undertaken underground and therefore only small quantity of dust will be generated if proper watering facilities are provided. Spoil will be transported by lorries and uploaded to the barging facility which will be designed to handle the predicted usage of 43 vehicles per hour during peak hour. The sensitive receiver nearest to the barging facility is the existing Kowloon Station topside residential development located at approximately 200m away and 28m above the local ground. This receiver has been included in the dust assessment.

5.3.2 Emission Inventory

Dust impact assessments have been carried out based on conservative assumption of the general construction activities which include the following:

· Heavy construction activities including site clearance, ground excavation, cut and fill operations, construction of the associated facilities, drill-and-blasting, as well as all construction traffic and hauling over the sites;

· Wind erosion of all open sites, including stockpile and barging area;

· An active operating area of 30% is assumed at any one time;

· Construction working periods of 26 days a month and 12 hours a day; and

· Loading/unloading from trucks at barging area and stockpiles.

The dust emission factors for different construction activities were extracted from the USEPA “Compilation of Air Pollution Emission Factors (AP-42)”, 5th Edition^[5-4]. Calculation of dust emission factors is given in Appendix 5-1 and the key assumptions are summarised in Table 5-2 below. For easy reference, the locations of ASRs assessment points and worksites, and the dust emission rates input into the model are presented in Appendix 5-2.

Table 5-2: Calculation of Dust Emission Factors

Activities	Reference [Note 1]	Operating Sites (see Figure 5-3)	Equations & Assumptions [Note 1] (see Appendix 5-1 for details)
Heavy construction activities including land clearing, ground excavation, cut and fill operations, construction of the facilities, drill & blast, equipment traffic and hauling over the site areas	S.13.2.3.3	All construction and excavation sites	E = 1.2 tons/acre/month of activity or = 2.69Mg/hectare/month of activity
Wind Erosion	S.11.9, Table 11.9.4	All construction sites, stockpile areas, barging area (all open sites)	E = 0.85 Mg/hectare/yr (24 hour emission)
Loading/Unloading at barging points and stockpile	S13.2.4	Barging point and stockpiles	k is particle size multiplier U is average wind speed M is material moisture content

[Note 1] Extracted from USEPA Compilation of Air Pollution Emission Factors (AP-42)

Dust emission from construction vehicle movement will be limited within the confined worksites area and the equation in AP-42 S.13.2.3.3 has taken this factor into account. Watering facilities will be provided at every designated vehicle exit point. Since all vehicles will be washed at exit points and vehicle loaded with the dusty materials will be covered entirely by impervious sheeting before leaving the construction site, dust nuisance from construction vehicle movement outside the worksites is unlikely to be significant.

The loaded vehicles will move to the stockpiling areas where C&D materials will be unloaded immediately. The vehicles will then be washed again before leaving the stockpiles in order to minimise generation of dusty materials. Vehicles movement within the stockpiling areas will be very limited and dust emission from vehicle hauling at these areas will therefore be insignificant. The major dust generating activities at stockpiling areas will be originated mainly from wind erosion and loading/unloading of materials; and these have been assumed in the FDM.

The design of the barging facility will be similar to the one being used in the East Rail Extension Project in Hung Hom Bay, with the following features:

· All road surfaces within the barging facility will be paved;

· Dust enclosures will be provided along the loading ramps to avoid dust dispersion;

· Vehicles will be required to pass through designated wheel washing facilities before leaving the barging facility.

The vehicles will transport to the barging facilities, unload the C&D materials under the dust enclosure, and then be washed before leaving to avoid dispersion of dust. Vehicles movement within the barging areas will also be very limited and dust emission will be insignificant. Similar to the stockpiling areas, it has assumed in the FDM that the major dust generating activities at barging areas will be originated mainly from wind erosion and loading/unloading of materials.

5.4 Assessment Methodology

Dust impact assessment has been undertaken using the Fugitive Dust Model (FDM) as approved by USEPA and EPD. It is a well-known Gaussian Plume model designed for computing air dispersion model for fugitive dust sources. Modelling parameters including dust emission factors, particles size distributions, surface roughness, etc are referred to in EPD’s “Guideline on choice of models and model parameters” ^[5-5] and USEPA’s AP-42. The density of dust is assumed to be 2.5gm^-3. A background TSP concentration is taken as 98 µgm^-3 in accordance with the “urban” category in EPD’s Guidelines on Assessing “TOTAL” Air Quality Impacts ^[5-6]. A surface roughness of 100cm is assumed in the model to represent the terrain.

Real meteorological data on wind direction, wind speed, temperature and stability were collected from the nearest weather station, the Hong Kong Observatory Station, for Year 1999 to 2001. The anemometer height at Hong Kong Observatory Station is 42m above ground.

Fugitive dust modelling has been conducted at heights 1.5m, 5m, 10m, 15m, 20m and 25m above local ground level for each year. The maximum cumulative 1-hour and 24-hour averaged TSP concentrations at the selected ASRs were determined. A 20x20m grid contour was employed on the study area to investigate the general pollutant distribution for the worst assessment year.

5.5 Assessment Results

The worst-case scenarios at each respective ASR will occur under different meteorological conditions (e.g. different wind directions). Assessment results of the dust impact from KSL alone and cumulative impact from concurrent project are presented as follows:

1) Dust impacts from construction of KSL only (unmitigated scenario);

2) Dust impacts from construction of KSL only (mitigated scenario); and

3) Cumulative dust impacts from both KSL and concurrent project (mitigated scenario).

5.5.1 “Unmitigated” Scenario for Construction of KSL

The maximum predicted 1-hour and 24-hour TSP levels for construction of KSL are summarised in Table 5-3. Dust impacts are high at ASRs under the “unmitigated” scenario, and the predicted hourly and 24-hour averaged TSP concentrations exceed TM-EIA requirements at some sensitive receivers. The maximum predicted TSP hourly concentration is 889.5µg/m³ at Lai Chack Middle School (A36). Details of the assessment results are given in Appendix 5-3.

Table 5-3 : Predicted 1-hour and 24 hour TSP concentrations at 1.5m above the local ground (worst affected Scenario) under the “unmitigated” scenario for construction of KSL

		Unmitigated Scenario
ASR No	ASR Description	Predicted 1-hr TSP conc^[1]	Predicted 24-hr TSP conc^[2]
1	New World Centre	299.7	118.1
2	New World Centre (The Amazon)	438.3	215.4
3	Sheraton Hong Kong Hotel	610.0	348.2
4	The Peninsula Hotel	430.2	253.1
5	Hong Kong Space Museum	354.1	240.7
6	YMCA of Hong Kong	520.7	290.6
7	Old Fire Station Building	635.6	240.4
8	Hong Kong Cultural Centre	413.1	235.9
9	Star House	296.9	154.3
10	The Marco Polo Hong Kong Hotel	330.7	165.3
11	Former Marine Police Headquarters	237.9	133.2
12	Hankow Centre	212.6	147.8
13	No.1 Peking Road	412.2	265.3
14	Consumer Education Information Centre	225.8	130.1
15	No. 11-39 Ashley Road	229.0	132.6
16	No.2-12 Canton Road	316.8	163.8
17	No.4-8 Canton Road	254.8	134.1
18	Lippo Sun Plaza	267.6	124.3
19	Silvercord Centre	294.2	128.2
20	No.30-41 Haiphong Road	283.2	144.4
21	Imperial Building (facing Canton Road)	336.7	134.8
22	Imperial Building (facing KPDCP)	344.5	133.1
23	Ocean Centre, New T&T and World Commercial Center	252.0	125.3
24	Marco Polo Gateway Hotel	289.3	132.0
25	Harbour City & World Finance Center	338.5	141.1
26	Hanley Building (facing Canton Road)	371.1	141.3
27	Hanley Building (facing KPDCP)	382.2	140.9
28	The Marco Polo Prince Hotel	374.0	149.0
29	Manley Building	423.2	158.2
30	The Gateway	427.5	161.8
31	The Royal Pacific Hotel and Towers	498.1	167.6
32	China Hong Kong City	489.2	185.0
33	Tsim Sha Tsui Fire Station	733.3	251.5
34	FSD Kowloon South Divisional HQ	816.9	298.2
35	Canton Road Government School	724.4	275.1
36	Lai Chack Middle School	889.5	312.8
37	Victoria Tower	879.6	295.6
38	No.1-3A Austin Road, Wai On Building	546.6	232.7
39	The Harbour Side	182.0	138.0
40	The Waterfront	255.6	179.0
41	Sorrento	284.5	189.8
42	No.51 Jordan Road, Lee Kiu Building	376.9	237.5
43	New Headquarters for the Hong Kong Girl Guides Association with hostels	669.5	356.0
44	Man King Building	813.6	429.4
45	Yau Ma Tei Catholic Primary School	322.2	166.3
46	HKMA David Li Kwok Po College	372.2	162.9
47	Charming Garden	761.0	255.2
48	Park Avenue	248.3	155.3
49	Central Park	327.3	193.4
50	Island Harbourview	208.3	134.9
51	Olympian City One	242.4	157.4
52	HSBC Centre	468.0	287.8
53	Skyway House	448.8	260.3
54	Olympic Station Phase 3 Project and Olympian City Phase 3 (Under construction)	631.0	326.5
55	Tai Kok Tsui Catholic Primary School (Hoi Fan Road)	177.3	125.6
56	Sir Ellis Kadoorie Secondary School (West Kowloon)	172.0	115.6
57	West Kowloon Disciplined Services Quarters	196.4	135.4
58	Metro Harbourview (Under construction)	183.8	125.4
59	Nam Cheong Estate	221.7	130.5
60	Fu Cheong Estate	189.5	116.1

Notes

[1] An hourly averaged TSP concentration of 500µg/m³ should not be exceeded

[2] A 24-hour averaged TSP concentration of 260µg/m³ should not be exceeded

[3] Bold figures indicate the predicted TSP levels has exceeded EPD’s standards

5.5.2 “Mitigated” Scenario for Construction of KSL

The unmitigated TSP concentrations (in Table 5-3) above are high at ASRs along Canton Road and near WKN. However, under a good site practice with regular watering, dust suppression could be achieved. In accordance with USEPA AP-42, watering twice a day could generally reduce dust emission by half and hence the dust concentration by 50%.

With proper watering (at least four times a day for WKN and twice a day for the remaining sections) throughout the construction phase (Figure 5-4), the 1-hour and 24-hour TSP levels are predicted as shown in Table 5-4. Details of the assessment results are given in Appendix 5-4.

Table 5-4 : Predicted 1-hour and 24 hour TSP concentrations at 1.5m above the local ground (worst affected level) under the “mitigated” scenario for construction of KSL (Watering at least four times a day for WKN and at least twice a day for the remaining sections)

		Mitigated Scenario
ASR No	ASR Description	Predicted 1-hr TSP conc^[1]	Predicted 24-hr TSP conc^[2]
1	New World Centre	198.8	105.8
2	New World Centre (The Amazon)	268.2	153.4
3	Sheraton Hong Kong Hotel	354.0	223.1
4	The Peninsula Hotel	264.1	175.5
5	Hong Kong Space Museum	220.3	168.7
6	YMCA of Hong Kong	309.3	194.3
7	Old Fire Station Building	366.8	169.2
8	Hong Kong Cultural Centre	255.6	167.0
9	Star House	197.4	126.1
10	The Marco Polo Hong Kong Hotel	214.4	131.6
11	Former Marine Police Headquarters	161.1	114.5
12	Hankow Centre	147.2	122.9
13	No.1 Peking Road	255.1	181.6
14	Consumer Education Information Centre	142.4	114.1
15	No. 11-39 Ashley Road	142.8	110.2
16	No.2-12 Canton Road	207.4	130.9
17	No.4-8 Canton Road	161.5	116.1
18	Lippo Sun Plaza	158.9	108.7
19	Silvercord Centre	166.8	108.3
20	No.30-41 Haiphong Road	160.3	113.7
21	Imperial Building (facing Canton Road)	179.0	110.4
22	Imperial Building (facing KPDCP)	180.8	110.4
23	Ocean Centre, New T&T and World Commercial Center	155.4	107.4
24	Marco Polo Gateway Hotel	166.8	109.4
25	Harbour City & World Finance Center	180.9	112.2
26	Hanley Building (facing Canton Road)	188.7	112.6
27	Hanley Building (facing KPDCP)	192.8	113.2
28	The Marco Polo Prince Hotel	190.8	115.1
29	Manley Building	203.1	120.1
30	The Gateway	205.2	119.5
31	The Royal Pacific Hotel and Towers	223.9	119.2
32	China Hong Kong City	224.9	123.9
33	Tsim Sha Tsui Fire Station	288.3	141.1
34	FSD Kowloon South Divisional HQ	310.8	153.1
35	Canton Road Government School	277.0	149.1
36	Lai Chack Middle School	323.6	159.0
37	Victoria Tower	327.6	154.4
38	No.1-3A Austin Road, Wai On Building	223.7	133.2
39	The Harbour Side	149.7	121.8
40	The Waterfront	176.4	135.5
41	Sorrento	191.2	143.9
42	No.51 Jordan Road, Lee Kiu Building	191.5	134.7
43	New Headquarters for the Hong Kong Girl Guides Association with hostels	280.6	172.9
44	Man King building	411.8	245.0
45	Yau Ma Tei Catholic Primary School	200.6	129.9
46	HKMA David Li Kwok Po College	235.1	128.3
47	Charming Garden	429.5	176.6
48	Park Avenue	173.1	125.3
49	Central Park	211.0	144.4
50	Island Harbourview	145.3	116.3
51	Olympian City One	164.1	127.7
52	HSBC Centre	279.5	185.9
53	Skyway House	260.2	177.3
54	Olympic Station Phase 3 Project and Olympian City Phase 3 (Under construction)	355.3	211.1
55	Tai Kok Tsui Catholic Primary School (Hoi Fan Road)	132.3	111.8
56	Sir Ellis Kadoorie Secondary School (West Kowloon)	129.8	106.8
57	West Kowloon Disciplined Services Quarters	144.7	115.9
58	Metro Harbourview (Under construction)	138.4	111.0
59	Nam Cheong Estate	154.5	113.7
60	Fu Cheong Estate	140.9	106.4

Notes

[1] An hourly averaged TSP concentration of 500µg/m³ should not be exceeded

[2] A 24-hour averaged TSP concentration of 260µg/m³ should not be exceeded

Results indicate that by increasing frequency of watering to at least four times a day for the WKN (reducing the dust emission by 75%;) and by watering twice a day for the remaining section (reducing the dust emission by 50%), the predicted 1-hour and 24-hour TSP levels at all ASRs will comply with the TM-EIA. There would be no adverse dust impact caused by the construction of KSL.

5.5.3 Cumulative Dust Impacts from Concurrent Projects

5.5.3.1 West Kowloon Cultural District

(a) During the Overlapping Period with Construction of KSL Tunnel & Station

The location of WKCD is indicated in Figure 1-2-2. The latest information for WKCD at the time of preparing this EIA is available from the government website. It is noted that the proposal for WKCD has been submitted in mid June 2004. According to Addendum No. 3 to the Invitation for Proposal for the WKCD ^[5-7] issued on 30 March 2004, the construction of the WKCD is anticipated to commence in April 2007. There is currently no available information on construction programme / method / phasing.

The cumulative dust impacts from WKCD are considered to be insignificant and short term only due to the following reasons:

· There are no major KSL construction activities in the vicinity of WKCD. In accordance with the construction programme of KSL, all excavation works for WKN will be completed by September 2006. The remaining works are construction of superstructure and station fitting out works of which insignificant dust impacts are anticipated. The overlapping period for the major excavation (if any) of WKCD and the superstructure construction of WKN would be relatively short from May to Sept 2007 (and possibly shorter or even no overlapping at all taking into account 2-3 months of mobilisation period of WKCD on site).

· The site formation work for WKCD has been completed. Except for the construction of basements (e.g. carparks), other major excavations are not expected and most of the construction activities would be superstructure and fitting out works which would only generate insignificant dust. Its cumulative dust impacts on KSL during the interfacing period would be minor.

(b) During the Overlapping Period with Operation of Barging Facility and Stockpiles for KSL

The barging facility and two stockpiles (at south of the WKN) in the vicinity of WKCD will be operated from January 2005 to end of 2007. The ASRs that would most likely be affected by cumulative dust impacts are the topside residential towers (The Harbour Side and The Waterfront) at MTRC Kowloon Station, for which the podium level is at about 28m above the local ground.

These two works areas are located at 150-250m from the nearest ASRs. There will be no construction activities except for loading and unloading of C&D materials (only 43 trucks per hour transporting from work sites to barging facility and 6 trucks per hour transporting from work sites to each of the two stockpiles). The stockpiles will be covered by impervious sheet; while the loading ramps in the barging facility will be designed with dust enclosures. Dust impacts on these ASRs due to the operation of these two works areas are therefore anticipated to be minor. It can be seen in Appendix 5-4 that the predicted hourly TSP levels at The Harbour Side and The Waterfront at 25m high as a result of the construction of KSL project are 116 mgm^-3 and 119 mgm^-3, respectively with 98mgm^-3 TSP background concentration. Hence, the contribution of KSL to the cumulative dust impacts during the overlapping period with WKCD from May to end of 2007 would be insignificant only. In addition, since all excavation works of KSL will be completed by commencement of the construction of WKCD, it is also expected that the operation of the barging facility and two stockpiles will be reduced during the concurrent period.

5.5.3.2 Post Secondary College & China Light Power Electricity Substation

The proposed post-secondary college (Figure 1-2-2) is located at the junction of Hoi Ting Road and Hoi Wang Road and will be constructed in 2005/2006. The China Light Power (CLP) electricity substation is planned at Lai Cheung Road (Figure 1-2-2) and is scheduled to be constructed in late 2004 for completion in 2007. The ASR that would most likely be affected by the cumulative dust impacts is Yau Ma Tei Catholic Primary School, which is about 150m at the east of KSL and about 100m at the north-west of post-secondary college and 150m at the north of the CLP electricity substation. It is anticipated that most of the construction activities for these two concurrent projects would be superstructure works, which would not generate significant dust. Its cumulative dust impacts on KSL are therefore considered to be insignificant.

5.5.3.3 Secondary School

The proposed secondary school (Figure 1-2-2) is located at the junction of Hoi Wang Road and Yau Cheung Road. The construction is scheduled to commence in 2007/08 and for completion by 2009/10. There is no other information available on construction programme / method / phasing at this stage. In accordance with the construction programme of KSL, all excavation works for this section of the WKN northern tunnel will be completed by 2007, and the remaining superstructure, backfilling and road reinstatement work will be taken from December 2006 to May 2007. Taking into account 2 months of mobilisation period of the school project, the constructions are very unlikely to be undertaken concurrently. Nevertheless, it is also anticipated that the construction activities for the secondary school would mainly be superstructure works, which would not generate significant dust. Its cumulative dust impacts on KSL, if any, are therefore considered to be insignificant.

5.5.3.4 Cultural Square Development & Hong Kong Girl Guides Association Headquarter

The proposed Cultural Square Development is located at Salisbury Road (Figure 1-2-1) and Hong Kong Girl Guides Association Headquarter is located at the junction of Jordon Road and Ferry street (Figure 1-2-2). Both projects will be constructed concurrently with KSL from 2005 to 2007. Similarly, since the construction activities for these two projects would mainly be superstructure works only, they would not generate significant dust. Cumulative dust impacts on KSL are therefore considered to be insignificant.

5.5.3.5 Pedestrian Piazza

The proposed pedestrian piazza is located at the existing Star Ferry Public Transport Interchange (PTI) (Figure 1-2-1) and the works for the open plaza would commence in 2007 for completion in 2008. Its construction will likely be undertaken concurrently with the construction of Salisbury Road tunnel section and the reinstatement works of the TBM retrieval shaft of KSL in 2007. There is no available information on construction programme and method at this stage. However, since the construction activities for pedestrian piazza would mainly be superstructure works only, they would not generate significant dust. Cumulative dust impacts on KSL are therefore considered to be insignificant.

5.5.3.6 Proposed Roads D12 (Eastern Section), D1 and D1A

It was noted that the proposed Road D12, D1 and D1A would come into operation at the same time with that of KSL in 2008. There is no available information on construction programme / method / phasing at this stage. However, it is advised that the construction work will be potentially entrusted to KCRC as a separate project, subject to confirmation (Figure 1-2-2). A separate Environmental Permit (EP) will be applied from EPD for construction and operation of the roadworks.

Subject to the confirmation on the potential entrustment of these roadworks to KCRC, the Project Proponent could schedule the construction works and allow programme phasing to avoid the concurrent activities to be undertaken in the vicinity. The construction of roadworks is likely to be commenced in late 2007 when all civil works of KSL are completed. Hence, there will be no cumulative dust impacts at the potentially sensitive receivers including Lai Chack Middle School, Victoria Tower and Wai On Building (ref. FSD Kowloon South Divisional Headquarter will be relocated at that time due to the construction of WKCD).

5.5.3.7 Redevelopment of FMPHQ

The construction of KSL will overlap with the redevelopment of FMPHQ. Cumulative dust impacts have been assessed based on the latest information from the approved Project Profile for FMPHQ. The construction of FMPHQ is tentatively divided into six stages of works: 1) tree retaining wall installation, retaining wall installation for main building, open cut excavation; 2) retaining wall installation for main building, open cut excavation; 3) Retaining wall installation for main building; 4) remaining excavation; 5) foundation work; and 6) superstructure work. Bulk excavation during site formation stage is anticipated to generate the most significant dust impact. A summary of the construction activities during the overlapping period of the two projects is given in Table 5-5.

Table 5-5 : Construction activities during the Overlapping Construction Period with FMPHQ

	Construction Activities
Period	KSL	FMPHQ
Mar 05 – May 05	Utilities diversion along Salisbury Road and at EEP and construction access shaft	Remaining excavation
Jun 05 – Mar 06	Remaining utilities diversion work at EEP and construction access shaft Temp wall & decking along Salisbury Road and at EEP and construction access shaft Excavation at EEP and construction access shaft	Remaining excavation + Superstructure work
Apr 06 – Oct 06	Excavation along Salisbury Road	Superstructure work

According to the programme for FMPHQ, bulk excavation is scheduled between mid 2004 and 2^nd quarter of 2005. Activities contributing to the fugitive dust impact during bulk excavation are identified as excavation, loading of materials to trucks for disposal at public filling area, transportation of materials and wind erosion. It is confirmed that watering of at least 4 times per day on all exposed worksites will be implemented for FMPHQ project; and the dust emission will be reduced by 75%.

The cumulative impacts have been modelled by taking the FMPHQ’s dust emission factors as provided by the project EIA consultant. Results indicate that with proper watering throughout the construction of KSL and FMPHQ projects, there will be no adverse cumulative dust impact. The following frequencies of watering are recommended and agreed by the respective project proponents:

· Four times a day for WKN for KSL project;

· Twice a day for the remaining section for KSL project; and

· Four times a day for the FMPHQ project.

A summary of mitigated cumulative 1-hour and 24-hour TSP concentrations is showed in Table 5-6. Contours of maximum cumulative 1-hour and 24-hour averaged TSP concentration for the worst scenario are presented in Figures 5-5 and 5-6. Results identified that all ASRs are within the TM-EIA limits, and there are no other ASR and sensitive uses within the exceedance areas. Details of the assessment results are given in Appendix 5-5.

Table 5-6 : Predicted Cumulative 1-hour and 24-hour TSP concentrations at 1.5m above the local ground at the worst meteorological hour under the “Mitigated” scenario

		Cumulative Dust Impact (Mitigated Scenario)
ASR No	ASR Description	Cumulative 1-hr TSP conc^[1]	Cumulative 24-hr TSP conc^[2]
1	New World Centre	216.3	107.0
2	New World Centre (The Amazon)	295.2	153.5
3	Sheraton Hong Kong Hotel	354.0	223.1
4	The Peninsula Hotel	264.1	175.5
5	Hong Kong Space Museum	268.4	169.7
6	YMCA of Hong Kong	309.3	194.3
7	Old Fire Station Building ^[3]	ASR 7 is not an ASR during FMPHQ project construction
8	Hong Kong Cultural Centre	255.6	167.0
9	Star House	259.9	164.3
10	The Marco Polo Hong Kong Hotel	308.1	154.7
11	Former Marine Police Headquarters^[3]	ASR 11 is not an ASR during FMPHQ project construction
12	Hankow Centre	190.5	143.1
13	No.1 Peking Road	255.1	190.3
14	Consumer Education Information Centre	199.9	146.7
15	No. 11-39 Ashley Road	164.4	117.2
16	No.2-12 Canton Road	214.5	164.4
17	No.4-8 Canton Road	199.0	147.9
18	Lippo Sun Plaza	170.8	130.8
19	Silvercord Centre	166.8	116.0
20	No.30-41 Haiphong Road	160.3	113.7
21	Imperial Building (facing Canton Road)	179.0	110.4
22	Imperial Building (facing KPDCP)	180.8	110.4
23	Ocean Centre, New T&T and World Commercial Center	180.1	122.5
24	Marco Polo Gateway Hotel	166.8	110.4
25	Harbour City & World Finance Center	180.9	112.2
26	Hanley Building (facing Canton Road)	188.7	112.6
27	Hanley Building (facing KPDCP)	192.8	113.2
28	The Marco Polo Prince Hotel	190.8	115.1
29	Manley Building	203.1	120.1
30	The Gateway	205.2	119.5
31	The Royal Pacific Hotel and Towers	223.9	119.2
32	China Hong Kong City	224.9	123.9
33	Tsim Sha Tsui Fire Station	288.3	141.1
34	FSD Kowloon South Divisional HQ	310.8	153.1
35	Canton Road Government School	277.0	149.1
36	Lai Chack Middle School	323.6	159.0
37	Victoria Tower	327.6	154.4
38	No.1-3A Austin Road, Wai On Building	223.7	133.2
39	The Harbour Side	149.7	121.8
40	The Waterfront	176.4	135.5
41	Sorrento	191.2	143.9
42	No.51 Jordan Road, Lee Kiu Building	191.5	134.7
43	New Headquarters for the Hong Kong Girl Guides Association with hostels	280.6	172.9
44	Man King building	411.8	245.4
45	Yau Ma Tei Catholic Primary School	200.9	130.1
46	HKMA David Li Kwok Po College	235.1	128.5
47	Charming Garden	429.5	176.6
48	Park Avenue	173.1	125.5
49	Central Park	211.2	144.5
50	Island Harbourview	146.0	116.3
51	Olympian City One	164.5	127.7
52	HSBC Centre	279.5	186.0
53	Skyway House	260.8	177.4
54	Olympic Station Phase 3 Project and Olympian City Phase 3 (Under construction)	356.2	211.2
55	Tai Kok Tsui Catholic Primary School (Hoi Fan Road)	132.9	111.8
56	Sir Ellis Kadoorie Secondary School (West Kowloon)	130.4	106.8
57	West Kowloon Disciplined Services Quarters	144.8	116.0
58	Metro Harbourview (Under construction)	138.6	111.1
59	Nam Cheong Estate	155.2	113.7
60	Fu Cheong Estate	141.2	106.5

Notes

[1] An hourly averaged TSP concentration of 500µg/m³ should not be exceeded

[2] A 24-hour averaged TSP concentration of 260µg/m³ should not be exceeded

[3] ASRs 7 & 11 are part of the FMPHQ redevelopment site. They are therefore not considered as ASRs during the construction of FMPHQ development. They are however considered as ASRs after the completion FMPHQ development.

5.6 Recommended Mitigation Measures

The Contractor is obliged to follow the procedures and requirements given in the Air Pollution Control (Construction Dust) Regulation^[5-8]. It stipulates the construction dust control requirements for both Notifiable (e.g. site formation) and Regulatory (e.g. road opening) Works to be carried out by the Contractor.

In accordance with the Air Pollution Control (Construction Dust) Regulation, the following dust suppression measures should also be incorporated by the Contractor to control the dust nuisance throughout the construction phase:

l Any excavated or stockpile of dusty material should be covered entirely by impervious sheeting or sprayed with water to maintain the entire surface wet and then removed or backfilled or reinstated where practicable within 24 hours of the excavation or unloading;

l Any dusty materials remaining after a stockpile is removed should be wetted with water and cleared from the surface of roads or streets;

l A stockpile of dusty material should not be extend beyond the pedestrian barriers, fencing or traffic cones;

l The load of dusty materials on a vehicle leaving a construction site should be covered entirely by impervious sheeting to ensure that the dusty materials do not leak from the vehicle;

l Where practicable, vehicle washing facilities with high pressure water jet should be provided at every discernible or designated vehicle exit point. The area where vehicle washing takes place and the road section between the washing facilities and the exit point should be paved with concrete, bituminous materials or hardcores;

l When there are open excavation and reinstatement works, hoarding of not less than 2.4m high should be provided as far as practicable along the site boundary with provision for public crossing. Good site practice shall also be adopted by the Contractor to ensure the conditions of the hoardings are properly maintained throughout the construction period;

l All main haul roads should be paved with concrete, bituminous materials, hardcores or metal plates, and kept clear of dusty materials; or sprayed with water or a dust suppression chemical so as to maintain the entire road surface wet;

l The portion of any road leading only to construction site that is within 30m of a vehicle entrance or exit should be kept clear of dusty materials;

l Surfaces where any pneumatic or power-driven drilling, cutting, polishing or other mechanical breaking operation takes place should be sprayed with water or a dust suppression chemical continuously;

l Any area that involves demolition activities should be sprayed with water or a dust suppression chemical immediately prior to, during and immediately after the activities so as to maintain the entire surface wet;

l Where a scaffolding is erected around the perimeter of a building under construction, effective dust screens, sheeting or netting should be provided to enclose the scaffolding from the ground floor level of the building, or a canopy should be provided from the first floor level up to the highest level of the scaffolding;

l Any skip hoist for material transport should be totally enclosed by impervious sheeting;

l 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;

l 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;

l 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;

l Exposed earth should be properly treated by compaction, turfing, hydroseeding, vegetation planting or sealing with latex, vinyl, bitumen, shotcrete or other suitable surface stabiliser within six months after the last construction activity on the construction site or part of the construction site where the exposed earth lies;

l The areas within 30m from the blasting area should be wetted with water prior to blasting;

l No blasting should be carried out when strong wind signal or tropical cyclone warning signal no. 3 or higher is hoisted.

By implementing these control measures and with good construction site practice, it is anticipated that dust impacts will be insignificant. It is recommended that the Contractor should undertake proper watering on all exposed spoil (with at least 4 times per day for WKN and 2 times per day for the remaining sections) throughout the construction phase. The barging facility should be designed with dust enclosures along the loading ramps to avoid dust dispersion. All road surfaces within the barging facility should be paved. Watering should be undertaken twice a day over the work area and all vehicles are required to pass through designated wheel washing facilities before leaving the barging facility. Figure 5-4 illustrates the locations and extent for the implementation of dust control measures.

These requirements should be incorporated into the Contract Specification for the civil work. In addition, an audit and monitoring programme during the construction phase should be implemented by the Contractor to ensure that the construction dust impacts are controlled to within the HKAQO. Detailed requirements for the audit and monitoring programme is given separately in the EM&A manual.

5.7 Residual Impacts

No residual dust impacts are expected if appropriate dust mitigation measures are adopted and incorporated during the construction phase.

5.8 Conclusion

Key representative ASRs for construction dust impacts have been identified. They comprise of residential uses, hotels, and schools. Other sensitive uses within 500m from the site boundary include playgrounds, open space, parks etc. Currently there is no plan for topside developments on the proposed station.

Potential dust impact would be generated from the soil excavation activities, backfilling, site erosion, storage of spoil on site, transportation of soil, as well as underground blasting activities during the construction phase. Quantitative fugitive dust assessments have been conducted, taking into account the cumulative impact caused by nearby concurrent projects.

It is identified that there are concurrent projects that would potentially cause cumulative dust impacts. The likely impacts from most of the projects are considered to be only minor and insignificant, except for the contribution from redevelopment of FMPHQ which has been taken into consideration in the assessment. Results indicate that, with proper watering of at least 4 times per day for WKN and 2 times per day for the remaining sections throughout the construction phase of KSL and also watering of at least 4 times a day for FMPHQ project, the predicted TSP concentrations will comply with the statutory requirements. Effective dust control can also be achieved by implementing the procedures and requirements given in the Air Pollution Control (Construction Dust) Regulation and the EM&A programme during construction. With the implementation of dust suppression control and good site practice, adverse fugitive dust impact is not anticipated.

During operational phase, only Electric Multiple Units (EMUs) will be deployed during normal operation. It is anticipated that there will be no operational air quality impacts for the proposed KSL development. However, as a good design practice, it is recommended that exhaust louvres should be located away from air sensitive receivers. Intakes louvers would not have any adverse air quality impacts on neighbouring receivers.

6. Airborne Noise Impact Assessment

6.1 Construction Phase

6.1.1 Legislation and Standards

Control over construction noise is governed by the Noise Control Ordinance (NCO) (Cap 400) ^[6-1] and the EIAO and their subsidiary requirements. Various Technical Memoranda (TMs) have been issued under the NCO and the EIAO to stipulate control approaches and criteria. These TMs prescribe the maximum permitted noise levels for the use of Powered Mechanical Equipment (PME) and certain construction activities and processes, according to the type of equipment or activity, the perceived noise climate of the area, and the working hours of equipment operation and usage. The TMs applicable to the control of noise from construction activities in the current proposed KSL works are:

· TM on Noise from Construction Work other than Percussive Piling (TM-GW) ^[6-2];

· TM on Noise from Construction Work in Designated Areas (TM-DA) ^[6-3];

· TM on Environmental Impact Assessment Process (TM-EIAO) ^[6-4];

· TM on Noise from Percussive Piling (TM-PP) ^[6-5].

It is noted that use of any percussive sheet piling is governed under the TM-PP and separate application to EPD for Construction Noise Permit (CNP) would be required.

6.1.1.1 Noise Standards for Daytime

Noise arising from general construction works during daytime is governed by the TM-EIAO under the EIAO. Table 6-1 presents the recommended noise standards.

Table 6-1 : Noise standards for daytime (0700 to 1900 hours) construction activities

Uses	Acceptable Noise Standards Leq (30mins), dB(A)
All domestic premises including temporary housing accommodation	75
Hotels and hostels	75
Educational institutions including kindergartens, nurseries and all others where unaided voice communication is required HKCC and HKSM ^[note]	70 65 (during school examinations)

Note: The above standards apply to uses which rely on open windows for ventilation. Performance art centers (e.g. HKCC and HKSM) are also considered as NSRs according to the TM-EIAO and hence need to be considered. Since noise sensitivity of the HKCC and HKSM is regarded as similar to schools as mentioned in S7.1.1, a noise standard of 70dB(A) for daytime construction noise is therefore adopted.

In accordance with the TM-EIAO, the noise criteria as laid down in Table 6-1 for the construction of designated projects shall be met as far as practicable. All practicable mitigation measures shall be exhausted to avoid residual impacts to the maximum possible extent.

6.1.1.2 Noise Standards for Restricted Hours

The NCO provides statutory controls on general construction works during the restricted hours (ie 1900 to 0700 hours from Monday to Saturday and at any time on Sundays or public holidays). The use of PME for construction works during the restricted hours would require a CNP. The TM-GW details the procedures adopted by EPD for assessing such application. The granting of a CNP is subject to conditions stated in the permit and it may be revoked at any time for failure to comply with the permit conditions.

In addition to the general controls on the use of PME during the restricted hours, the use of Specified Powered Mechanical Equipment (SPME) and the undertaking of Prescribed Construction Work (PCW) during the restricted hours in a designated area are controlled by the TM-DA. Construction plant or equipment classified as SPME under the TM-DA includes hand-held breakers, bulldozers, concrete mixer lorries, dump trucks and poker vibrators. PCW includes the erection or dismantling of formwork or scaffolding, hammering, handling of rubble, wooden boards, steel bars, or scaffolding material, and the disposal of rubble through plastic chutes.

The TM-DA details the procedures that should generally be adopted by EPD for assessing the use of SPME during the restricted hours and for determining whether a CNP would be issued.

Maximum noise levels from construction activities during restricted hours at affected NSRs are controlled under the TMs and shall not exceed the specified Acceptable Noise Levels (ANLs). These ANLs are stipulated in accordance with the Area Sensitivity Ratings established for the NSRs. The ANLs for construction works in designated areas are more stringent than those given in the TM-GW, as reflected from the corresponding Basic Noise Levels (BNLs) stated in Table 6-2.

Table 6-2 : BNLs for construction noise other than percussive piling

Time Period	Basic Noise Levels for Area Sensitivity Ratings, dB(A)
	A	B	C
All weekdays during the evening (1900 to 2300 hours), and general holidays (including Sundays) during the day and evening (0700 to 2300 hours)	60 (45)	65 (50)	70 (55)
All days during the night-time (2300 to 0700 hours)	45 (30)	50 (35)	55 (40)

Note: Figures in brackets are BNLs for SPME construction work in designated areas

As defined in the Noise Control Designated Area Plan no. EPD/NP/KLN-01a, the whole KSL alignment and work sites are within the Designated Area.

6.1.1.3 Construction Noise Permits

Despite any description or assessment made in this EIA Report on construction noise aspects, there is no guarantee that a CNP will be issued for the project construction. The Noise Control Authority will consider a well-justified CNP application, once filed, for construction works within restricted hours as guided by the relevant TMs issued under the NCO.

The Noise Control Authority will take into account contemporary conditions / situations of adjoining land uses and any previous complaints against construction activities at the site before making a decision in granting a CNP. Nothing in the EIA report shall bind the Noise Control Authority in making a decision. If a CNP is to be issued, the Noise Control Authority shall include in it any conditions demand. Failure to comply with any such conditions will lead to cancellation of the CNP and prosecution action under the NCO.

6.1.1.4 Blasting

There are no statutory procedures and criteria under the NCO and EIAO for assessing the blasting impacts and are therefore beyond the scope of the EIA. However, the administrative and procedural control of all blasting operations in Hong Kong is vested in the Mines Division of the Civil Engineering and Development Department (CEDD). The Dangerous Goods (General) Regulations, Chapter 295 also stipulates that no person shall carry out blasting unless he possesses a valid mine blasting certificate to be issued by the Mines Division of CEDD. The Superintendent of Mines will review the application on a case-by-case basis before issuing the Mine Blasting Certificate.

6.1.2 Noise Assessment Methodology

6.1.2.1 Summary of Construction Methodology

The construction programme, sequence, methodology and plant inventory adopted for this assessment were provided by the Design Team. The construction work will commence in early 2005 and is scheduled to be completed by late 2007. Testing and commissioning of the railway system will then be conducted for target completion for operation in late 2008 / early 2009.

Tunnels along Salisbury Road will be constructed using cut-&-cover technique. Bored tunnelling will be adopted from south of WKN along Canton Road. For the tunnels to the north of WKN, cut-&-cover technique will be adopted. The construction activities will commence in the first 100m worksite sub-section, and after completion, the plant items will be relocated to the next sub-section. The spoil from all mucking-out locations will be transported by dump trucks to the barging facility at West Kowloon.

Detailed description on the construction methodologies for each work site is given in Chapter 4 and the associated construction plant inventory is given in Appendix 4-2.

6.1.2.2 General Assessment Procedures

Construction noise assessment will be conducted based on the following procedures:

· Determine the assessment area;

· Identify and locate representative NSRs that may be affected by the works;

· Obtain the construction method and work sequence for the construction period;

· Obtain the plant items for each corresponding construction work sequence;

· Determine the sound power levels of the plant items according to the information stated in the TM-GW or other recognised sources of reference, where appropriate;

· Calculate the correction factors based on the distance between the NSRs and the notional noise source positions of the work sites;

· Apply corrections for façade, distance, barrier attenuation, acoustic reflection where applicable;

· Predict construction noise levels at the NSRs;

· Quantify the level of impact at the NSRs, in accordance with TM-GW; and

· Predict the cumulative noise impacts for any concurrent construction works in the vicinity of the proposed work.

6.1.2.3 Determination of Assessment Area

The study area for the noise impact assessment includes all NSRs within 300m from the boundary of the project and its works sites. With the shielding from the first row of building blocks, the second row of NSRs will generally be protected. The assessment therefore focuses on the first row of NSRs that have direct line of sight within the project boundary and works sites.

6.1.2.4 Noise Sensitive Receivers

NSRs are chosen in accordance with Annex 13 of the TM-EIAO. Both existing and future planned uses during the construction period of KSL are included as appropriate. The existing NSRs are identified through desktop review and site surveys while the planned NSRs are identified from the latest Outline Zoning Plans ^{[6-6 to 6-10]}, Outline Development Plans and Layout Plans.

The landuses in the vicinity of the proposed alignment and station include schools, residential developments, commercial buildings and hotels. All hotels and performance venues are air-conditioned and do not rely on openable windows for ventilation. The key representative NSRs for noise assessment are given in Figure 6-1 and their respective locations are shown in Figures 6-2-1 to 6-2-3.

6.1.2.5 Construction Plant Inventory & Emission Inventory

Chapter 4 presents a detailed description of the key construction works required for each of the work site. The major construction works would include the following activities:

· Site clearance and formation activities;

· Structure dismantling;

· Station construction;

· Tunnel construction (including bored tunnelling);

· Installation of diaphragm walls or pipe pile walls;

· Underpinning of subway, piers and footbridge;

· Diversion of box culverts;

· Spoils removal from underground works & stockpiling;

· Backfilling and reinstatement works; and

· Barging activities.

The above construction activities would require Powered Mechanical Equipment (PME) including breakers, pipe pile rigs, excavators, lorries, mobile cranes, concrete pumps, concrete mixers, pokers, rollers, etc. The Sound Power Levels (SWLs) for each PME without mitigation measures are given in Appendix 6-1.

The construction of the proposed works involves different construction activities and plant items at different stages. For cut-&-cover sections along Salisbury Road, at shaft areas, and between Lin Cheung Road and Lai Cheung Road where temporary decking will be installed for traffic management, most of excavation works and tunnel construction will be undertaken beneath the deck. After installing the decking for cut-&-cover sections, the PMEs remaining at grade are assumed at the notional source position of the nearest worksite from the NSRs for worst-case assessment.

The plant inventory provided in Appendix 4-2 indicates the total number of PME for each route section along the railway alignment. For assessment purpose, it has been assumed that all PME items are evenly distributed over that area (unless otherwise specified), and the worksites were divided into a number of notional sources having a length to width ratio of approximately 5:1 for calculation. Locations of notional source and distance for NSRs are given in Appendix 6-2.

6.1.2.6 Utilisation Rates of Powered Mechanical Equipment

Practically, the PMEs will not be operating for all times within a work site. In this assessment, similar utilisation rates adopted in other approved EIA report ^[6-11] have been assumed. These are summarized below:

Table 6-3 : Utilisation rates of PME

PME	Utilisation Rate
Asphalt paver and roller	50%
Auger	65%
Circular saw	50%
Hand-held breaker, hydraulic breaker	80%
Lorries, excavators and crane lorries	65%
Mobile crane, crawler crane	30%
Pipe pile rigs and chisels	65%

6.1.2.7 Operation of the TBM Launching Shaft

The plant inventory for operation of the launching shaft is given in Appendix 4-2. Some of the construction plant items including TBM, diesel trains etc would be normally operating inside tunnels, except during the initial stage when the TBM just commences operation.

The TBM will operate 24 hours and the TBM launching shaft will be provided with a noise insulating cover which will be closed during restricted hours to shelter the plant items (see Chapter 4). The conveyor belt at the launching shaft will transfer the spoil from the bored tunnel to the adjoining Construction Area A7 (see S4.3.3). The conveyor system will be used to lift up the spoil from the bottom of the launching shaft to the ground level only (about 20m tall). The tentative location of conveyor belt is indicated in Figure 4-1-2, but is still subject to the detailed design. Spoil from A7 will then be transported by dump trucks to the barging facility in West Kowloon during the daytime.

When the TBM runs about 100m in the tunnel, the diesel train and mortar car will need to travel to and from along the tunnel to facilitate the tunnelling work. For conservative assessment, it is assumed that the TBM, diesel train and mortar car will be operating simultaneously. The following assumptions are made for the calculations for the unmitigated scenario.

· The noise insulating cover for the launching shaft will be closed during night-time and can achieve an overall noise reduction of 22dB(A). Typical configuration of acoustic panels that can achieve this insulation requirement is 1.5mm GS outer skin, 100mm acoustic infill (e.g. fibreglass) with 80kg/m³, and an inner perforated sheet (see Figure 6-3). Typical transmission loss at different frequency bands are 19dB at 125Hz, 25dB at 250Hz, 30dB at 500Hz, 35dB at 1000Hz, and 35dB at 2000Hz.;

· The ventilation fan will be installed with an sound attenuator (e.g. silencer) to reduce the noise impacts by 15dB(A);

· Enclosures with 10dB(A) reduction will be installed for conveyor belt and water pump;

· The motor of the gantry will be screened to provide a noise reduction of 5dB(A);

· The TBM noise emanating from the tunnelling will diminish when the TBM goes further to the south of the tunnel. However, for conservative assessment, such attenuation is not taken into consideration; and

· Since the TM-GW does not include noise data for TBM, diesel train and mortar car, reference has been made to the Sheung Shui to Lok Ma Chau Spur Line CNP application (ref GW-TN0374-03 dated Nov 2003) in this assessment.

6.1.2.8 Noise Assessment Tool

An in-house program has been used for the analysis of the construction noise calculations. The initial program runs were conducted without any mitigation measures. Where noise level exceedance were identified, further runs would be made assuming different combinations of mitigation measures to be incorporated.

6.1.3 Assessment Results for “Unmitigated” Scenario During Daytime

Assessment results indicate that, under “unmitigated” scenario, the construction noise impacts at some of the NSRs would exceed the criteria. The maximum unmitigated noise levels, including noise contribution from the construction plant in the launching shaft, and the exceedance over the criteria at the NSRs are shown in Table 6-4. Detailed results of construction noise assessment are given in Appendix 6-3.

The most affected residential building is Man King Building (N19), with a noise exceedance of 15dB(A), during the construction of WKN and northern tunnel. Canton Road Government School (N11) and Lai Chack Middle School (N12) would also be exposed to noise exceedance of 16dB(A).

Table 6-4 : Predicted maximum construction noise levels at the NSRs – “unmitigated” scenario

NSR No.	NSR Description	Unmitigated Scenario
		Max Predicted Noise Level, dB(A)	Exceedance, dB(A)^[1]
N1	Hong Kong Space Museum	82	12
N2	Hong Kong Cultural Centre	79	9
N3	Hankow Centre	72	0
N4	Not used
N5	Not used
N6	No.4-8 Canton Road	86	11
N7	Imperial Building (facing Canton Road)	82	7
N8	Hanley Building (facing Canton Road)	81	6
N9	Manley Building (facing Canton Road)	86	11
N10	FSD Kowloon South Divisional HQ	85	10
N11	Canton Road Government School	86	16
N12	Lai Chack Middle School	86	16
N13	Victoria Tower	78	3
N14	No.1-3A Austin Road, Wai On Building	81	6
N15	The Harbour Side	61 ^[4]	0
N16	The Waterfront	76	1
N17	Sorrento	78	3
N18	No.51 Jordan Road, Lee Kiu Building	80	5
N19	Man King Building	90	15
N20	Man Fai Building	86	11
N21	Man Yiu Building	83	8
N22	Man Cheong Building	82	7
N23	Man Wah Building	80	5
N24	Yau Ma Tei Catholic Primary School	77	7
N25	HKMA David Li Kwok Po College	78	8
N26	Charming Garden	84	9
N27	Park Avenue	75	0
N28	Central Park	84	9
N29	Island Harbourview	77	2
N30	Olympic Station Phase 3 Project and Olympian City Phase 3 (Under construction)	84	9
N31	Tai Kok Tsui Catholic Primary School (Hoi Fan Road)	71	1
N32	Sir Ellis Kadoorie Secondary School (West Kowloon)	69	0
N33	West Kowloon Disciplined Services Quarters	71	0
N34	Metro Harbourview (Under construction)	69	0
N35	Nam Cheong Estate	68	0

Note:

[1] Exceedance for schools are deducted from comparison with the normal noise criterion of 70dB(A)

[2] Bold figures indicate that the predicted noise levels have exceeded the criteria in TM-EIAO.

[3] The HKSM and HKCC are provided with central A/C and hence the predicted noise levels are for information only.

[4] Prediction of noise level at Harbour Side has included the contribution of haul road (i.e. 56dB(A)).

It is anticipated that there will be a total of about 43 lorries per hour transporting the spoils from the entire work sites to the barging facility. Noise contribution from the additional construction traffic to the existing roads would be very minimal. It is estimated that the noise level on the nearest NSR, i.e. The Harbour Side, due to the operation of dump trucks on haul road is only 56dB(A) (Appendix 6-3). Adverse noise impacts are therefore not anticipated. Details on timing for disposal, transportation routings of the trucks, locations of temporary stockpiles and barging facility, and location of disposal sites are presented in Chapter 9.

6.1.4 “Good Practice” Mitigation Measures

The predicted noise levels show that unmitigated construction activities could exceed the daytime noise criteria at some of the NSRs. Noise mitigation measures are therefore required to alleviate the noise impacts. Noise emissions from construction sites could be minimised by the following means:

· Good site practices to limit noise emissions at the source;

· Use of quiet plant and working methods;

· Use of site hoarding as noise barrier to screen noise at ground level of NSRs;

· Use of shrouds / temporary noise barriers to screen noise from relatively static PMEs;

· Scheduling of construction works outside school examination periods in critical area; and

· Alternative use of plant items within one worksite, wherever practicable.

The above mitigation measures would need to be implemented in all work sites as good practices. Detailed descriptions of these mitigation measures are given in the following sections.

6.1.4.1 Good Site Practices and Noise Management Techniques

Good site practice and noise management techniques could considerably reduce the noise impact from construction site activities on nearby NSRs. The following measures should be followed during each phase of construction:

· only well-maintained plant should be operated on-site and plant should be serviced regularly during the construction programme;

· machines and plant (such as trucks, cranes) that may be in intermittent use should be shut down between work periods or should be throttled down to a minimum;

· plant known to emit noise strongly in one direction, where possible, be orientated so that the noise is directed away from nearby NSRs;

· silencers or mufflers on construction equipment should be properly fitted and maintained during the construction works;

· mobile plant should be sited as far away from NSRs as possible and practicable; and

· material stockpiles, site office and other structures should be effectively utilised, where practicable, to screen noise from on-site construction activities.

The benefits of these techniques can vary according to specific site conditions and operations. The environmental noise climate would certainly be improved through these control practices, although the improvement can only be quantified during implementation when specific site parameters are known.

6.1.4.2 Use of Site Hoarding

Purpose built temporary noise barriers of 2.4m high located on the site boundaries between noisy construction activities and NSRs could generally reduce noise levels at low-level zone of NSRs through partial screening. In general this would provide minimum 5 dB(A) attenuation for the low level receivers. It would be possible for the Contractor to provide these in the form of site hoardings to achieve this attenuation effect, provided that the barriers have no openings or gaps and have a superficial surface density of at least 14kg/m². Good site practice shall also be adopted by the Contractor to ensure the conditions of the hoardings are properly maintained throughout the construction period. For conservative assessments, however, the site hoarding has not been taken into consideration in the construction noise assessments.

6.1.4.3 Use of Movable Noise Barrier & Full Enclosure for Relatively Static Plants

Movable temporary noise barriers that can be located close to noisy plant and be moved iteratively with the plant along a worksite can be very effective for screening noise from NSRs. A typical design which has been used locally is a wooden framed barrier with a small cantilevered upper portion of superficial density no less than 14kg/m² on a skid footing with 25mm thick internal sound absorptive lining. This measure is particularly effective for low level zone of NSRs. A cantilevered top cover would be required to achieve screening benefits at upper floors of NSRs.

Movable barriers or flexible acoustic mat (shrouds) will be used for some PME (e.g. pipe pile rigs, auger). It is anticipated that suitably designed barriers /acoustic mats could achieve at least 5 - 10dB(A) reduction. For a conservative assessment, only a reduction of 5dB(A) is assumed.

The use of full enclosure has been considered in this assessment to shelter relatively static plant including air compressor, generator, grout pump. These enclosures can provide about 10dB(A) noise reduction. A sketch of typical noise enclosure /temporary barrier is attached in Figure 6-3.

A summary of the barrier, enclosure, and acoustic mat adopted for PMEs, and the associated noise reduction is given in Appendix 6-4.

6.1.4.4 Scheduling of Construction Works Outside School Examination Period

During school examination periods, the daytime construction noise criterion is 65dB(A) which is lower than the normal daytime school criterion of 70dB(A). Scheduling of construction works outside school examination period to less intrusive periods would definitely reduce the overall noise impacts at the NSRs for ensuring compliance with the construction noise criterion.

The Contractor shall liaise with the school representative(s) including, but not limited to Lai Chak Middle, Canton Road Government, Yau Ma Tei Catholic Primary, HKMA David Li Kwok Po College, and the planned schools that would receive student intake during the construction of the KSL (e.g. secondary school at junction of Hoi Wang Road and post secondary college at junction of Hoi Ting Road and Hoi Wang Road), to obtain the examination schedule and avoid noisy construction activities during school examination period.

6.1.4.5 Use of “Quiet” Plant and Working Methods

The use of quiet plant is a feasible solution to tackle adverse noise impacts associated with the construction works. It is generally known (supported by field measurement) that particular models of construction equipment are quieter than standard types given in the TM-GW. Whilst it is generally considered too restrictive to specify that the Contractor has to use specific models or items of plant, it is reasonable and practicable to set plant noise performance specifications for specific PME so that some flexibility in selection of plant is allowed. A pragmatic approach would be to request that the Contractor independently verifies the noise level of the plant proposed to be used and demonstrates through furnishing of these results, that the plant proposed to be used on the site meets the requirements.

The use of quiet plant associated with the construction works is prescribed in British Standard “Noise Control on Construction and Open Sites, BS5228: Part 1: 1997” which contains the SWLs for specific quiet PME. The SWLs for quiet PMEs adopted for the assessment are detailed in Appendix 6-5. It should be noted that while various types of silenced equipment could be found in Hong Kong, EPD when processing a CNP application for evening or night time works may apply the noise levels specified in the TM-GW and TM-DA. CNP applications which contain sufficient details of any particularly quiet items of PME or any special noise control measures which the CNP applicant proposes to employ on the site may be given special consideration by the Noise Control Authority.

6.1.4.6 Sequencing Operation of Construction Plant Equipment

In practice, some plant items will operate sequentially within the same work site, and certain reduction of the predicted noise impacts could be achieved. However, any additional control on the sequencing of plant will impose a restrictive constraint to the Contractor on the operation and planning of plant items, and the implementation of the requirement would be difficult to be monitored. Hence, sequencing operation of PME has not been taken into consideration in the construction noise assessments, except those specified in S6.1.2.6 for which the realistic operating time has been incorporated.

6.1.4.7 Use of Quieter Plants at TBM Launching Shaft

It is proposed to use quieter plant to alleviate the noise impacts at the launching shaft. The noise data for quieter compressor and ventilation fan used in the Spur Line Construction CNP application is also adopted (see Appendix 6-6 for details).

6.1.5 Assessment Results for “Mitigated” Scenario During Daytime - “Good Practice” Mitigation Measures

Noise reduction from the use of mitigation measures including quiet plant, noise barrier, acoustic mat and enclosure for construction plants as described in S6.1.4 has been applied in the assessment. However, no screening correction for site hoarding has been assumed in the model for conservative analysis. Detailed results of construction noise assessment for “mitigated” scenario (with contributions from the launching shaft) are given in Appendix 6-6. The predicted noise levels and the exceedance over daytime construction noise criteria are summarised in the following Table 6-5.

Table 6-5 : Predicted maximum construction noise levels at the NSRs – “mitigated” scenario – with good practices

NSR No.	NSR Description	Mitigated Scenario
		Max Predicted Noise Level, dB(A)	Exceedance, dB(A)^[1]
N1	Hong Kong Space Museum	71	1
N2	Hong Kong Cultural Centre	69	0
N3	Hankow Centre	62	0
N4	Not used
N5	Not used
N6	No. 4-8 Canton Road	75	0
N7	Imperial Building (facing Canton Road)	71	0
N8	Hanley Building (facing Canton Road)	70	0
N9	Manley Building (facing Canton Road)	75	0
N10	FSD Kowloon South Divisional HQ	75	0
N11	Canton Road Government School	74	4
N12	Lai Chack Middle School	74	4
N13	Victoria Tower	72	0
N14	No.1-3A Austin Road, Wai On Building	75	0
N15	The Harbour Side	59 ^[4]	0
N16	The Waterfront	69	0
N17	Sorrento	71	0
N18	No.51 Jordan Road, Lee Kiu Building	73	0
N19	Man King Building	81	6
N20	Man Fai Building	77	2
N21	Man Yiu Building	75	0
N22	Man Cheong Building	74	0
N23	Man Wah Building	73	0
N24	Yau Ma Tei Catholic Primary School	69	0
N25	HKMA David Li Kwok Po College	69	0
N26	Charming Garden	75	0
N27	Park Avenue	67	0
N28	Central Park	75	0
N29	Island Harbourview	68	0
N30	Olympic Station Phase 3 Project and Olympian City Phase 3 (Under construction)	76	1
N31	Tai Kok Tsui Catholic Primary School (Hoi Fan Road)	64	0
N32	Sir Ellis Kadoorie Secondary School (West Kowloon)	62	0
N33	West Kowloon Disciplined Services Quarters	64	0
N34	Metro Harbourview (Under construction)	62	0
N35	Nam Cheong Estate	61	0

Note:

[1] Exceedance for schools are deducted from comparison with the normal noise criterion of 70dB(A)

[2] Bold figures indicate that the predicted noise levels have exceeded the NCO criteria.

[3] The HKSM and HKCC are provided with central A/C and hence the predicted noise levels are for information only.

[4] Prediction of noise level at Harbour Side has included the contribution of haul road (i.e. 56dB(A)).

With the use of recommended noise mitigation measures described in S6.1.4, construction noise impacts at the NSRs could be reduced but still there will be exceedances at some of the NSRs over daytime construction criteria. A maximum noise level of 81dB(A) is found at Man King Building (N19) and 74dB(A) at Canton Road Government School (N11) and Lai Chack Middle School (N12), respectively.

6.1.6 Further Specific Mitigation Measures Considered

Further specific mitigation measures have been investigated in order to reduce the noise impacts to the maximum practicable extent at the remaining affected NSRs, including the Canton Road Government School (N11), Lai Chack Middle School (N12), Man King Building (N19), Man Fai Building (N20), and Olympian City Phase 3 (N30). Details of the results are presented separately for each NSR in the following sections and summarized in Appendix 6-7.

6.1.6.1 Schools

Assessment results indicate that the noise impacts at the two schools are caused by the ground treatment works for the bored tunnel sections in front of them. The total duration for the noise exceedance over the 70dB(A) criterion is 2 months. Noise contributions from other construction works, such as the launching shaft and the WKN which are much further away, are less significant. The current assessment has assumed the worst case that ground treatment would be required (i.e. approximately 2 months for each 50m sub-section). The detailed design will be conducted by the Design & Build Contactor at a later stage, and he would further review the need for ground treatment for the section along Canton Road, taking into account any specific construction methodology for the bored tunnelling. If the construction methodology developed by the Design & Build Contractor confirms that the less ground treatment is required, the actual environmental impacts would be less than that predicted in this EIA Report.

(a) Specific Mitigation Measures 1 : Temporary Noise Barrier for Particular PME

The ground treatment work would require drill hole machine, grout pump, crane lorry and air compressor. Since the use of quiet plants and movable barrier/enclosure for drill hole machine, grout pump and air compressor have been already recommended in S6.1.4, a possible effective mitigation measures for further investigation is the use of temporary noise barrier for the crane lorry during ground treatment.

It is found that the use of temporary noise barrier for the crane lorry is not effective to reduce the noise impacts at the two schools. The predicted noise impacts and the duration of exceedance are given in Table 6-6.

Table 6-6 : Noise impacts at schools – with temporary noise barrier for particular PME

NSR	Description	Noise Impacts, dB(A)			Duration in different noise band (Month)^[1]
		Criterion	Max Impacts	Exceedance	71 – 75 dB(A)^[2]	76 – 79 dB(A)	80 – 84 dB(A)
N11	Canton Road Government School	70	74	4	2	0	0
N12	Lai Chack Middle School	70	74	4	2	0	0

Note:

[1] Total duration of noise exceedance (i.e. the sum of individual exceedance duration for all activities) is given.

[2] The noise level band between 71 dB(A) and 75 dB(A) applies to schools only.

(b) Specific Mitigation Measures 2 : Large Full Enclosure

Another possible mitigation measures is the use of large full enclosure for all noisy plants during the ground treatment work. A larger full enclosure would provide better noise attenuation than the use of temporary noise barriers / acoustic mats. However, the height of the enclosure would need to be at least 7m in order to accommodate all the plant. Given the nature of Canton Road, having such a tall barrier would impose adverse visual impacts to the neighbouring receptors and pedestrians, especially for the Canton Road Government School and the Lai Chack Middle School which their boundaries would be within 10m. Together with potential nuisance / impacts on the access to the schools, the use of large enclosure would cause significant impacts and hence is considered as not practicable. It is therefore not recommended to implement such a measure for the relatively short duration of noise exceedance (i.e. 2 months) during the construction period.

(c) Specific Mitigation Measures 3 : Scheduling of Works

The noise exceedance could possibly be avoided at the schools if the ground treatment work is scheduled to be carried out during the insensitive period, e.g. summer vacation. However, this mitigation measures will pose a constraint on the construction programme to the Contractor and thus prolonging the overall construction duration as well as nuisance to the schools. It is also considered that there may be supplementary classes or extra-curriculum activities during the school vacation and hence scheduling of the works may not be practicable. However, it is still recommended the Contractor to consult with the school representatives to confirm the practicality of scheduling such works to tie in with long school vacations and the arrangement of summer courses during this period.

All noise mitigation measures, whichever practicable and effective, have been exhaustively investigated. Residual noise impacts for the schools are described in S6.1.7.

6.1.6.2 Man King Building and Man Fai Building

The predicted noise impacts at Man King Building and Man Fai Building, after implementing the “good practice” mitigation measures described in S6.1.4 are 81dB(A) for a duration of 17 months and 77dB(A) for a duration of 10 months (refer to Table 6-5 & Appendix 6-6). The remaining affected dwelling is the southern and western facades facing the tunnel section immediately to the north of the WKN. The major noise contributing sources are emanated from the construction activities of the tunnelling work and diversion of box culvert in front of the Man King Building. In order to further reduce the noise impacts, the following mitigation measures have been further considered.

(a) Specific Mitigation Measures 1 : Temporary Noise Barrier for Particular PME

Since most of the relatively static plants have already been sheltered by either a movable barrier, acoustic mats or enclosure (S6.1.4), the remaining noisy sources from the worksite in front of the Man King Building are hydraulic breaker, lorry/dump truck, concrete lorry mixer, concrete pump truck for tunnelling work and diversion of box culvert. The use of temporary noise barrier for these plant items has therefore been investigated. The following table summarises the predicted noise impacts for the scenario with installation of the temporary noise barrier for these particular PME at this section (Figure 6-4).

Table 6-7 : Noise impacts at Man King and Man Fai Buildings – with temporary noise barrier for particular PME

NSR	Description	Noise Impacts, dB(A)			Duration in different noise band (Month)^[1]
		Criterion	Max Impacts	Exceedance	71 – 75 dB(A)^[2]	76 – 79 dB(A)	80 – 84 dB(A)
N19	Man King Building	75	80	5	NA	15	0
N20	Man Fai Building	75	75	0	NA	0	0

Note:

[1] Total duration of noise exceedance (i.e. the sum of individual exceedance duration for all activities) is given.

[2] The noise level band between 71 dB(A) and 75 dB(A) applies to schools only.

It can be seen that the use of temporary noise barrier for mitigating noise generated from hydraulic breaker, lorry, concrete lorry mixer for the tunnel section to the south of Man King Building will reduce the noise impacts by 1dB(A) from 81dB(A) to 80dB(A), and the duration of exceedance will be reduced from 17 months to 15 months; and the associated noise impacts at Man Fai Building will be reduced to within the noise criterion. Detailed results of the noise assessment are given in Appendix 6-7.

(b) Specific Mitigation Measures 2 : Sequencing of Construction Activities

Since movable temporary barriers have been used for all noisy PMEs as far as practicable, sequencing of construction activities for tunnelling work at the nearest worksite in front of Man King Building is investigated. The tunnel section will be originally constructed from both the southern and northern ends towards the middle in relatively short sections of about 100m long. Discussion with the Design Team suggests that it is feasible to construct the 100m long tunnel immediately in front of Man King Building in 2 sub-sections sequentially (Figure 6-4). This approach will reduce the total amount of PMEs operating within that area and hence the associated noise impacts. Appendix 6-7 shows the PME inventory, work programme and a sketch showing the approximate demarcation of the 2 sub-sections, and the noise prediction results.

Assessment results indicate that, after sequencing the construction activities, the noise impact will be reduced to 77dB(A) with only 2dB(A) exceedance for a duration of 4 months at Man King Building (see Appendix 6-7).

(c) Specific Mitigation Measures 3 : Large Full Noise Enclosure

The use of large full enclosures or large cantilevered noise barriers to screen the entire tunnel section has also been studied in order to further reduce the noise impacts. However, to ensure the construction plant items can move and transverse freely inside the enclosures or large cantilevered noise barrier, the minimum height should be as high as about 9m and for a length of about 100m.

Given the close proximity of the enclosure / large cantilevered noise barrier to the NSRs, such a massive structure would cause adverse visual impacts to the residents in Man King Building. It is also estimated that the foundation construction for such an extensive enclosure / large cantilevered barrier would be about 2-3 months. The foundation works of the enclosure / large cantilevered noise barrier would require piling rigs to be located relatively close to Man King Building, the noise impacts caused by the piling rigs on Man King Building would also be significant. It is noted that Man King Building does not have a podium and the lowest residential floor is only about 3-4 m above the local ground. Hence, the visual impacts on the low level receivers, especially those in north-west corner of Man King Building, will be very significant. On this basis, the use of large full noise enclosure is not considered as practicable. In addition, implementing such a noise enclosure can only benefit for 2dB(A) for a period of 1-2 months. The environmental benefits are only minimal and hence it is not recommended to implement this large full enclosure.

6.1.6.3 Olympian City Phase 3

The predicted noise impacts at Olympian City Phase 3, after implementing the “good practice” mitigation measures as described in S6.1.4, is 76dB(A) for a duration of 4 months (refer to Table 6-5 & Appendix 6-6). The dominant noise sources are caused by the construction activities during the installation of D-wall for tunnelling work. Further mitigation measures have been considered to mitigate the noise impacts.

(a) Specific Mitigation Measures 1 : Temporary Noise Barrier for Particular PME

Use of temporary noise barrier for mitigating noise generated from concrete lorry mixer, concrete pump truck, lorries/dump truck at the tunnel section immediately in front of the Olympian City Phase 3 development (Figure 6-4) has been found to be effective in reducing the construction noise impacts to within noise criterion (Table 6-8). No residual impact is anticipated.

Table 6-8 : Noise impacts at Man King Building – with temporary noise barrier for particular PME

NSR	Description	Noise Impacts, dB(A)			Duration in different noise band (Month)^[1]
		Criterion	Max Impacts	Exceedance	71 – 75 dB(A)^[2]	76 – 79 dB(A)	80 – 84 dB(A)
N30	Olympian City Phase 3	75	75	0	NA	0	0

Note:

[1] Total duration of noise exceedance (i.e. the sum of individual exceedance duration for all activities) is given.

[2] The noise level band between 71 dB(A) and 75 dB(A) applies to schools only.

Olympian City Phase 3 development is being constructed up to the lower residential floors during the time of preparing this EIA. It would take about 1-2 years for the completion of construction, fitting out and subsequent issue of the occupation permit. The above assessment has assumed that the NSR will be occupied during KSL construction as the worst-case assessment. In case it is not occupied at the time of KSL construction at this tunnel section, the Contractor should revisit the need of the proposed mitigation measures before the actual construction activities commence.

6.1.7 Residual Impacts During Daytime

All practicable direct mitigation measures including use of temporary barrier for particular plant items, large full enclosure, scheduling of construction works, and sequencing of construction activities (see S6.1.4 to S6.1.6 above) have been investigated and exhaustively used in order to alleviate the construction noise impacts. Assessment results indicate that with the incorporation of all recommended mitigation measures, there are still minor exceedance over the daytime construction noise criteria at one residential building and two schools. The residual impacts and durations of noise exceedance due to construction of KSL are summarised in Table 6-9.

Table 6-9 : Residual construction noise impacts

NSR	Description	Noise Impacts, dB(A)			Duration in different noise band (Month)^[1]
		Criterion	Max Impacts	Exceedance	71 – 75 dB(A)^[2]	76 – 79 dB(A)	80 – 84 dB(A)
N11	Canton Road Government School	70	74	4	2	0	0
N12	Lai Chack Middle School	70	74	4	2	0	0
N19	Man King Building	75	77	2	N/A	4	0

Note:

[1] Total duration of noise exceedance (i.e. the sum of individual exceedance duration for all activities) is given.

[2] The noise level band between 71 dB(A) and 75 dB(A) applies to schools only.

Since all the practicable direct noise mitigation measures (including quieter plant, temporary noise barriers, large full enclosures, scheduling of construction activities and sequencing of construction activities, as elaborated in S6.1.4 to S6.1.6) have been implemented, Indirect Technical Remedies (ITR) have been considered by the Project Proponent as the last resort for mitigating residual construction noise impacts.

ITR would generally require the consideration to upgrade the glazing (if necessary) for the facades that would be subject to excessive residual noise. In addition, the provision of air-conditioning would also be considered for those units subject to residual noise impacts. Erecting scaffolding to the exterior of the receivers may be required to upgrade the glazing. If necessary, the construction workers would need to get access to the units to replace the glazing and the air-conditioning equipment. After all the replacement works are completed, the scaffolding would need to be dismantled. The whole process would take 1-2 months, depending on the site conditions.

With reference to the East Rail Extension Hung Hum to Tsim Sha Tsui EIA Final Report (ERE EIA) ^[6-12] which is also prepared by the Project Proponent, the eligibility criteria proposed for qualifying the receivers for ITR are dependent on the severity of the residual noise impact and duration of exceedance after implementing all practicable direct mitigation measures. The eligibility criteria are given as follow:

· A residual impact of 5dB(A) or more (During the upgrading of glazing and provision of air-conditioning, the use of powered tools (eg electric drills) and general activities by the workers would generate high noise levels within the premises. The Project Proponent considers that the requirements of having the 5dB(A) above the criterion for consideration of ITR is appropriate) ; and

· A duration of noise exceedance of equal or more than 1 month (As explained above, ITR work would take about 1-2 months for implementation. Hence, it is not considered appropriate by the Project Proponent to consider ITR for any residual noise impacts shorter than 1 month).

Results indicate that none of the remaining affected NSRs would be qualified for ITR. Nonetheless, preliminary site inspection suggests that most of the classrooms of these schools have been provided with upgraded glazing and air-conditioning.

6.1.8 Cumulative Construction Noise Impacts from Concurrent Projects During Daytime

6.1.8.1 FMPHQ

The redevelopment of FMPHQ will be undertaken concurrently with KSL works (Figure 1-2-1). According to the latest information provided by the FMPHQ developer, the construction is planned for 30 months and will commence in early 2004 and hence will overlap with KSL. Cumulative construction noise impact is considered.

Hankow Centre is the only residential premise that would be potentially affected by concurrent constructions of both KSL and FMPHQ redevelopment. As mentioned in Chapter 5, the construction of FMPHQ is tentatively divided into six stages of works, including:

1) Tree retaining wall installation, retaining wall installation for main building, open cut excavation;

2) Retaining wall installation for main building, open cut excavation;

3) Retaining wall installation for main building;

4) Remaining excavation;

5) Foundation work; and

6) Superstructure work.

The cumulative noise levels at different construction phases for the mitigated scenario at Hankow Centre are summarised in Table 6-10 below. Results show that the predicted cumulative noise levels at Hankow Centre will be within the relevant criteria at all stages and residual impact is therefore not anticipated.

Table 6-10 : Cumulative Construction Noise Levels at N3 Hankow Centre

	Construction Activities		Predicted Noise Level dB(A)
Period	KSL	FMPHQ	KSL	FMPHQ^[1]	Cumulative
Mar 05 – May 05	Utilities diversion along Salisbury Road	Remaining excavation	58	70	70
Jun 05 – Mar 06	Temp wall & decking	Remaining excavation + superstructure work	61	69	70
Apr 06 – Oct 06	Excavation	Superstructure work	59	68	69

Note:

[1] Results have been made reference to the approved Project Profile of FMPHQ.

[2] Results are only presented for overlapping construction period.

6.1.8.2 WKCD

The latest information for WKCD at the time of preparing this EIA is available from the government website. It is noted that the proposal for WKCD has been submitted in mid June 2004. According to Addendum No. 3 to the Invitation for Proposal for the WKCD ^[1-7] issued on 30 March 2004, the construction of the WKCD is anticipated to commence in April 2007. There is no available information on the construction programme / method / phasing at this stage.

The Canton Road Government School (N11), Lai Chack Middle School (N12), Victoria Tower (N13) and No.1-3A Austin Road, Wai On Building (N14) are the NSRs that would be potentially affected by the cumulative impacts from both WKCD and KSL projects. An assessment has been conducted to evaluate the potential cumulative noise impacts caused by the construction of WKCD. It is anticipated that the construction of WKCD would involve mainly piling and superstructure. Information from other approved EIA report ^[6-13] for large site formation work and building construction suggests that the typical sound power levels of the groups of PME for piling and superstructure, or drainage / utility would be 113dB(A). On this basis, the potential cumulative noise contributions from the WKCD have been predicted (see Appendix 6-8) and are summarised below:

Table 6-11 : Cumulative construction noise impacts from WKCD

NSR	Description	Noise Levels, dB(A)			Criterion, dB(A)	Exceedance, dB(A)
		KSL	WKCD	Total
N11	Canton Road Government School	74	69	75	70	5
N12	Lai Chack Middle School	74	69	75	70	5
N13	Victoria Tower	72	66	73	75	0
N14	No.1-3A Austin Road, Wai On Building	75	64	75	75	0

Note: According to the Invitation for Proposal for WKCD, N10 (FSD Kowloon South Divisional HQ) will be relocated as part of the WKCD development project. Hence, as far as the cumulative construction noise impacts from WKCD are concerned, it is not considered as a NSR.

The exceedance at the two schools is caused by the construction of KSL only and all practicable direct mitigation measures have been considered exhaustively including good site practices, use of temporary barrier for particular plant items, quiet plants, typical movable barriers and enclosures, and scheduling of construction works (see S6.1.4 and S6.1.6.1 above). No other mitigation measures is considered to be practicable and effective to reduce the residual impact and the duration of the impacts after exhausting the use of direct mitigation measures is 2 months, as laid down in Table 6-9 above.

It should be noted that WKCD is a Designated Project under the EIAO. Hence, the project proponent of WKCD would need to conduct a separate EIA study for separate approval to address all the impacts during its construction and operational phase. The results for the above table should therefore be considered as for information only and be subject to detailed assessment by the project proponent of WKCD.

6.1.8.3 Post Secondary College

The proposed post-secondary college (Figure 1-2-2) is located at the junction of Hoi Ting Road and Hoi Wang Road and will be constructed in 2005/2006. Yau Ma Tei Catholic Primary School is identified as the only NSRs that would be potentially affected. Similar to the WKCD, a notional sound power level of 113dB(A) has been assumed for assessment of the cumulative construction noise impact for this school. Results are given in Appendix 6-8 and summarised below. Cumulative noise impacts on Yau Ma Tei Catholic Primary School would not exceed the 70dB(A) criterion.

Table 6-12 : Cumulative construction noise impacts from post secondary school

NSR	Description	Noise Levels, dB(A)			Criterion, dB(A)	Exceedance, dB(A)
		KSL	School	Total
N24	Yau Ma Tei Catholic Primary School	69	64	70	70	0

Nonetheless, it is recommended that the Contractor shall liaise with the school representative(s) of the college if it would receive student intake during the construction of the KSL to obtain the examination schedule and avoid noisy construction activities during school examination periods.

6.1.8.4 Roads D12 (Eastern Section), D1/ D1A

Subject to the confirmation on potential entrustment of the Roads D12, D1 and D1A to KCRC (Figure 1-2-2), the Project Proponent could schedule the construction works and allow programme phasing to avoid the concurrent activities to be undertaken in the vicinity. The construction of roadworks is likely to be commenced in late 2007 when all civil works of KSL are completed. Hence, there will be no cumulative noise impacts at the potentially sensitive receivers including Lai Chack Middle School, Victoria Tower and Wai On Building (ref. FSD Kowloon South Divisional Headquarter will be relocated at that time due to the construction of WKCD). Nonetheless, a separate Environmental Permit (EP) will be applied from EPD for construction and operation of the roadworks.

6.1.8.5 Cultural Square Development & Pedestrian Piazza

The proposed Cultural Square Development is located at Salisbury Road (Figure 1-2-1). It is anticipated that the construction works will be undertaken concurrently with KSL from 2005 to 2007. The proposed pedestrian piazza is located at the existing Star Ferry Public Transport Interchange (PTI) (Figure 1-2-1) and the works would commence in 2007 for completion in 2008. However, there are only hotels and performance art centres in the vicinity of the area and all of these developments are provided with central air conditioning and do not rely on open window for ventilation. Cumulative noise impacts are therefore not anticipated.

6.1.8.6 Hong Kong Girl Guides Association Headquarter

The proposed Hong Kong Girl Guides Association Headquarter is located at the junction of Jordon Road and Ferry street (Figure 1-2-2). It is anticipated that the construction works will be undertaken concurrently with KSL from 2005 to 2007. Assuming a notional sound power level of 113dB(A) for assessment of the cumulative construction noise impact for this development, results are given in Appendix 6-8 and summarised below.

Table 6-13 : Cumulative construction noise impacts from Hong Kong Girl Guides Association Headquarter

NSR	Description	Noise Levels, dB(A)			Criterion, dB(A)	Exceedance, dB(A)
		KSL	Headquarter	Total
N19	Man King Building	77	67	77	75	2
N23	Man Wah Building	73	76	78	75	3

The exceedance at Man King Building is caused by the construction of KSL only and all practicable direct mitigation measures have been considered exhaustively including good site practices, use of temporary barrier for particular plant items, quiet plants, typical movable barriers and enclosures, and sequencing of construction activities (see S6.1.4 and S6.1.6.2 above). No other mitigation measures is considered to be practicable and effective to reduce the residual impact and the duration of the impacts after exhausting the use of direct mitigation measures is 4 months, as laid down in Table 6-9 in S.6.1.7.

On the other hand, the noise exceedance at Man Wah Building is mainly contributed by the construction of the Hong Kong Girl Guides Association Headquarter. It is recommended that the mitigation measures shall be reviewed by the Design & Build Contractor, subject to the detailed construction programme of the Headquarter. The duration would also be subject to the details of the construction programme, and would be for the worst case up to a maximum of 2 years from Year 2005 to 2007 for the entire construction period of the Headquarter.

6.1.8.7 Secondary School

The proposed secondary school (Figure 1-2-2) is located at the junction of Hoi Wang Road and Yau Cheung Road. The construction is scheduled to commence in 2007/08 and for completion by 2009/10. There is no other information available on construction programme / method / phasing at this stage. In accordance with the construction programme of KSL, all excavation works for this section of the WKN northern tunnel will be completed by 2007, and the remaining superstructure, backfilling and road reinstatement work will be taken from December 2006 to May 2007. Taking into account 2 months of mobilisation period of the school project, the constructions are very unlikely to be undertaken concurrently.

Assuming a notional sound power level of 113dB(A) for assessment of the cumulative construction noise impact, it is identified that the predicted cumulative noise level on the most likely affected NSR, i.e. Man Cheong Building (N22), caused by the construction of the secondary school will still comply with the noise criterion. Results are given in Appendix 6-8 and summarised below.

Table 6-14 : Cumulative construction noise impacts from secondary school

NSR	Description	Noise Levels, dB(A)			Criterion, dB(A)	Exceedance, dB(A)
		KSL	School	Total
N22	Man Cheong Building	72 ^[1]	66	73	75	0

Note:

[1] The figure is the maximum predicted construction noise level caused by KSL at N22 during Year 2007 (i.e. the possible concurrent period)

6.1.8.8 China Light Power Electricity Substation

The proposed CLP electricity substation (Figure 1-2-2) is planned at Hoi Wang Road (Figure 1-2-2) and is scheduled to be construction in late 2004 for completion in 2007. The NSR that would most likely be affected by the cumulative noise impact is Yau Ma Tei Catholic Primary School which is about 150m at the north of the electricity substation. Similarly, by assuming a notional sound power level of 113dB(A) for the project, it is identified that the cumulative noise level on Yau Ma Tei Catholic Primary School (N24) will not exceed the 70dB(A) criterion. Results are given in Appendix 6-8 and summarised below.

Table 6-15 : Cumulative construction noise impacts from CLP electricity substation

NSR	Description	Noise Levels, dB(A)			Criterion, dB(A)	Exceedance, dB(A)
		KSL	Substation	Total
N24	Yau Ma Tei Catholic Primary School	69	65	70	70	0

6.1.9 Operation of Launching Shaft during Restricted Hours

The TBM will operate 24 hours and the TBM launching shaft will be provided with a noise insulating cover. This cover will be closed during restricted hours to shelter most of the PMEs inside. The Contractor would be required to apply for a CNP from EPD for its works during the restricted hours. There will not be any plant operating above ground during restricted hours when the noise insulating cover is shut. The gantry above the cover will also not be operating during restricted hour.

6.1.9.1 Noise Sensitive Receivers & Noise Criteria

The nearest NSRs that would be affected during restricted hours and the night time noise criterion are summarised in Table 6-16 below. The locations of these NSRs are illustrated in Appendix 6-9.

Table 6-16 : NSRs and criteria for restricted hours

Ref	NSRs	Area Sensitivity Rating	Night-time Criterion, dB(A)
N10	FSD Kowloon South Divisional HQ	B	50
N13	Victoria Tower	B	50

The Area Sensitivity Ratings are determined based on the best available information at the EIA study stage. The Area Sensitivity Ratings determined in this EIA Report are unlikely to be different at the time of project implementation unless there are substantial changes such as building redevelopment or land use change in the near vicinity of the NSRs. The Noise Control Authority would process any CNP application taking into consideration the construction method and condition prevailing at the time in accordance with the procedures laid down in the relevant technical memoranda issued under the NCO.

In any event, the Area Sensitivity Ratings assumed in this EIA Report is for indicative assessment only given that there would be changes to the developments (as well as their timing) in the vicinity of the proposed railway alignment. It should be noted that fixed noise sources are controlled under section 13 of the NCO. At the time of investigation, the Noise Control Authority shall determine noise impact from concerned fixed noise sources on the basis of prevailing legislation and practices being in force, and taking account of contemporary conditions/situations of adjoining land uses. Nothing in this EIA Report shall bind the Noise Control Authority in the context of law enforcement against all the fixed noise sources being assessed.”

6.1.9.2 Assessment Results

There are two key stages for the night-time works as far as construction noise is concerned. The first stage is when the TBM has just started the boring process. During this stage, the diesel train and mortar car do not need to operate. The noise assessment has taken into consideration a number of assumptions for unmitigated scenario as described in S6.1.2.7. In particular, the cover for the launching shaft will be closed during night-time and it can achieve an overall noise reduction of 22dB(A).

Assessment indicates that, for the unmitigated scenario, the night-time noise impacts on the receiver would be 53dB(A), exceeding the noise criterion by 3dB(A). It is therefore proposed to use quieter plant to alleviate the noise impacts. The quiet construction methods during night-time are described in S6.1.2.7 and S6.1.4.7. The resultant noise impacts after using quieter plant are 49dB(A) which are within the noise criterion and there are no residual noise impacts during night-time. Further noise mitigation measures are therefore not required. Appendix 6-9 also presents the calculations for both the unmitigated and mitigated scenarios.

6.1.9.3 Summary of Recommended Mitigation Measures During Restricted Hours

A summary of the noise mitigation measures for the TBM launching shaft during restricted hours is given below:

Table 6-17 : Mitigation measures for PME working in the launching shaft during restricted hours

Construction Plant/Worksite	Mitigation Measures
Launching shaft	Noise insulating cover to be shut
Ventilation fan	Silencer + Quieter plant
Compressor	Quieter plant
Conveyor belt	Acoustic enclosure
Water pump	Acoustic enclosure

6.1.10 Other Recommendations

6.1.10.1 Continuous Noise Monitoring

A continuous noise monitoring mechanism will also be implemented and operated by the Contractors throughout the entire construction period. This mechanism will include a system for reporting the real time monitoring results on the Project Proponent’s website within a period of time, to be agreed by EPD, after the relevant noise monitoring data are collected. In cases where exceedance is found, the Contractor and Environmental Team (ET) should take immediate actions to implement remediation measures. The EM&A Manual has specified the roles of ET / Independent Environmental Checker (IEC) / Contractor, Engineer etc on the continuous noise monitoring system. The general system requirements are also be outlined.

6.1.10.2 Blasting

Blasting is administrated by the Mines Division of CEDD. According to the Dangerous Goods Ordinance, the Contractor shall obtain a valid Blasting Permit from the Mines Division before carrying out any blasting in HK. When submitting the application for the blasting Permit, the Contractor shall enclose a method statement including manner of working and protective measures to protect adjacent land and property when blasting is carried out at different parts of the site and at different stages of blasting. Proposal to ensure compliance with the limits on ground vibration should be included. The application shall also include relevant plans approved by Building Ordinance Office showing any restrictions and conditions regarding blasting proposal, adjacent properties and structures (within plan radius of 300m), power lines, water main and services ^[6-14]. The blasting shall also be conducted by a qualified blasting specialist processing a valid Blasting Certificate issued by the authority ^[6-15].

In order to minimize the risk of loss in human life and damage to properties, the number of blasts per day and the maximum charge to be detonated will be limited. According to current design information, there will be up to 2 times of detonations per day for the drill-&-blast tunnels underneath the FMPHQ. The construction period of the drill-&-blast tunnels would be about 11 months. All the detonation will be conducted underground within the tunnels.

The nearest sensitive receiver is the HKCC. The distance from the drill-&-blast tunnel to the HKCC is between 40m and 160m. The YMCA and the Omni HK Hotels are located at a similar distance as HKCC. The other more critical sensitive receiver is the HKSM located at about 160m to 280m away. The most critical sensitive receiver for the noise generated by the blasting is therefore the HKCC.

It should be noted that each blast will only last for a fraction of second. Depending on the charge weights, impulsive noise of very short duration may be audible at some of the receivers. In order to minimise the nuisance of the short duration of the blasting noise, the Contractor shall implement the following mitigation measures:

· The Contractor shall establish a communication channel with HKCC and HKSM to liaise on the blasting schedule.

· The Contractor shall inform the HKCC and HKSM any scheduled blasting in advance.

· Sufficient time shall be allowed for alerting all the potential sensitive receivers including HKSM, HKCC, etc through established channel of communication prior to each and every blasting activity.

· In case the HKCC and HKSM have any special rehearsals / events that would not allow short impulsive noise even for a certain period in a day, the Contractor shall re-schedule the blasting to suit.

· Proper procedures shall be put in place to alert and minimise any startling effect on the vehicle drivers and pedestrians.

· Subject to detailed design to be conducted by the Contractor (i.e. a Design and Built Contractor), trial tests could be conducted to evaluate the optimal amount of charge to be used for each blasting.

Since blasting will be conducted during periods when there are no special rehearsal / events in the HKCC and HKSM, construction noise monitoring for underground blasting of the drill-&-blast tunnel is not necessary.

6.2 Operational Phase

6.2.1 Legislation and Standards

Noise from railway, station plant items and ventilation shafts is controlled under the NCO and the associated Technical Memorandum on Noise from Places Other Than Domestic Premises, Public Places or Construction Sites (TM-Places) ^[6-16], and the relevant noise criteria are listed in Table 1A, Annex 5 of TM-EIA. Table 6-18 below summarises the noise standards for railway noise.

Table 6-18: Noise criteria for railway noise

Area Sensitivity Rating	Time Period ^[1]	Acceptable Noise Levels (ANL), LAeq, 30 mins, dB(A) dB(A)	Maximum A-weighted sound pressure level, Lmax (2300-0700hrs) dB(A)
A	Day & evening	60	85
	Night	50
B	Day & evening	65
	Night	55
C	Day & evening	70
	Night	60

Note:

[1] Day: 0700 to 1900 hours, Evening: 1900 to 2300 hours, Night: 2300 to 0700 hours

According to TM-EIA, fixed plant noise levels should be 5dB(A) below the appropriate ANLs stipulated in TM-Places, or the prevailing noise levels, whichever is lower. The ANLs for different Area Sensitivity Ratings are summarised Table 6-19.

Table 6-19: Operational noise criteria for fixed noise sources

Area Sensitivity Rating	Time Period ^[1]	Acceptable Noise Levels (ANL), LAeq, 30 mins, dB(A)	ANL for Fixed Plant Noise (ANL-5), L eq, 30 mins, dB(A)
A	Day & evening	60	55
	Night	50	45
B	Day & evening	65	60
	Night	55	50
C	Day & evening	70	65
	Night	60	55

Note:

[1] Day: 0700 to 1900 hours, Evening: 1900 to 2300 hours, Night: 2300 to 0700 hours

6.2.2 Determination of Assessment Area

The study area for the operational noise impact assessment includes all NSRs within 300m from the boundary of the alignment. The first row of buildings having direct line of sight to the alignment will be most affected. The second row of NSRs will generally be protected from the shielding effect of the first row of buildings. The assessment therefore focuses on the first row of NSRs that have direct line of sight to the alignment.

6.2.3 Noise Sensitive Receivers & Area Sensitivity Ratings

6.2.3.1 Noise Sensitive Receivers

The existing NSRs to be assessed for operational noise would be the same as those for construction noise. In addition, any future NSRs are also included in the assessment to minimise any constraints on future developments. These future NSRs include planned residential developments in Tsim Sha Tsui and West Kowloon as shown in Figures 6-1 and 6-2-1 to 6-2-3.

6.2.3.2 Area Sensitive Ratings

The Area Sensitivity Ratings are defined in accordance with the relevant TMs. Determination of the Area Sensitivity Ratings for the NSRs in this study has been made reference to other approved EIA reports including WR EIA ^[6-18] and ERE EIA^[6-12]. The study area is classified as “urban”. An Area Sensitivity Rating of “B” is assigned for the NSRs not influenced by road traffic noise from major roads, and an Area Sensitivity Rating of “C” for NSRs indirectly influenced by road traffic noise from main roads.

In accordance with The Annual Traffic Census 2002 ^[6-19], the Area Sensitivity Rating for NSRs located at Canton Road (from Salisbury Road to Kowloon Park Drive) and Haiphong Road should be “B”. For NSRs close to northern part of Canton Road (from Austin Road to Jordan Road), Ferry Street, and West Kowloon Highway (between Austin Road West and Jordan Road (station no. 3502), the Area Sensitivity Rating should be “B”. The West Kowloon Highway is not considered as an influencing factor given the setback distance. For other receivers further north, the Area Sensitivity Rating should be “C”.

The Area Sensitivity Ratings are determined based on the best available information at the EIA study stage and are unlikely to be different at the time of project implementation unless there are substantial changes such as building redevelopment or land use changes in the near vicinity of the NSRs. Nothing in this EIA report shall bind the Noise Control Authority in the context of law enforcement against any fixed noise sources being assessed.

6.2.3.3 Prevailing Noise Levels

Noise measurements have been conducted to establish the prevailing noise levels along the proposed alignment. A summary is given in Table 6-20.

Table 6-20: Prevailing noise levels along the proposed alignment

Area	Time Period ^[1]	Prevailing Noise Levels, dB(A) L eq, 30 min, dB(A)
Along Canton Road	Day & evening	66 - 73
	Night	63 - 66
West Kowloon	Day & evening	62 - 70
	Night	63 –71
Charming Garden	Day & evening	68 - 73
	Night	67 - 70

Note:

[1] Day: 0700 to 1900 hours, Evening: 1900 to 2300 hours, Night: 2300 to 0700 hours

6.2.3.4 Noise Criteria

A summary of the noise criteria at NSRs caused by fixed plant noise is given in the following Table 6-21.

Table 6-21: Summary of noise criteria

Area	Time Period ^[1]	Prevailing Noise Levels, dB(A) [1]	Area Sensitivity Rating	ANL-5 dB(A) [2]	Criteria dB(A) min of [1] & [2]
Along Canton Road	Day & evening	66 - 73	B	60	60
	Night	63 - 66	B	50	50
West Kowloon	Day & evening	62 - 70	B	60	60
	Night	63 –71	B	50	50
Charming Garden	Day & evening	68 - 73	C	65	65
	Night	67 - 70	C	55	55

6.2.4 Emission Inventory of Noise Sources

6.2.4.1 Trains

All the tracks for KSL will be underground. The 150m tunnel section at Nam Cheong Park interfacing with WR is enclosed in a concrete box and will be covered with top soil (see S4.1). Hence, adverse operational train noise impacts are not anticipated.

6.2.4.2 Fixed Noise Sources

Operational noise will emanate from other fixed noise sources including:

· YMT Ventilation Building;

· CRPB; and

· WKN

The YMT Ventilation Building and CRPB will accommodate various plant items such as tunnel ventilation fans, transformers, pumps etc. For the WKN, there will be ventilation shafts to both the north and south ends of the station. Other major plant items to be accommodated in the WKN include fresh-water cooling facilities, ventilation fans, transformers, pumps etc.

Although there is no implementation plan for the topside properties, the ventilation shafts in WKN will be designed to be well above any podium level.

Figures 4-1 to 4-5 show the locations of YMT ventilation building, CRPB and WKN (ventilation shafts and E&M plants etc).

6.2.5 Assessment Methodology

Maximum allowable Sound Power Level (SWL) for above-grade louvres and ventilation plants have been established by considering the following:

· Separation distances and orientation from the nearest NSR(s);

· Cumulative noise impacts from other noise sources (e.g. other vent shafts) on the NSR; and

· Tonality, impulsiveness and intermittency based on TM-Places, where appropriate.

The above methodology has been adopted in the East Rail Extension Project ^[6-12] which is currently being implemented.

6.2.6 Assessment Results

Analysis has been conducted to quantify the preliminary near-field SWL criteria (Appendix 6-10). A summary of the SWL criteria is given in Table 6-22.

Table 6-22 : Summary of SWLs criteria for major fixed noise sources

Station	Plant Item	Distance to nearest NSRs, m	Maximum allowable Sound Power Level, dB(A)
			Daytime	Night-time
West Kowloon Station (South Block)	East Elevation	5	69	59
	South Elevation	5	76	66
	West Elevation	5	76	66
	North Elevation	5	69	59
West Kowloon Station	Fresh Water Cooling Towers	5	73	63
	Air Cooled Chillers	5	73	63
	Water Cooled Chillers	5	73	63
West Kowloon Station (North Block)	East Elevation	5	72	62
	South Elevation	5	72	62
	West Elevation	5	78	68
	North Elevation	5	78	68
Yau Ma Tei Ventilation Building	East Elevation	40	98	88
	South Elevation	50	98	88
	West Elevation	60	103	93
	North Elevation	60	101	91
Canton Road Plant Building	East Elevation	170	105	95
	South Elevation	170	110	100
	West Elevation	170	105	95
	North Elevation	170	104	96
Ventilation shaft of Emergency Egress Point	East Elevation	60	99	89
	South Elevation	60	98	88
	West Elevation	60	93	83
	North Elevation	60	94	84

Note: The above criteria are based on the assumption that the louvers are facing away from NSRs as a good design practice.

The above SWL criteria should be implemented and refined during the design development by the Contractor. Any new NSRs should also be identified and incorporated into the design as necessary. The Contractor shall install sound attenuators to ensure that the specified maximum SWLs in the above table are achieved. The performance of the sound attenuators shall be obtained by comparing the total SWL of noise emanating from the facade and the specified maximum SWL specified in the above Table 6-22.

6.2.7 Recommendation of Mitigation Measures

The detailed design should incorporate the following good practice in order to minimise the nuisance on the neighbouring NSRs.

· Louvres should be orientated away from adjacent NSRs, preferably onto main roads (e.g. Kowloon Park Drive, West Kowloon Expressway) which are less sensitive.

· Direct noise mitigation measures including silencers, acoustic louvers and acoustic enclosures should be allowed for in the design for various ECS plant.

· The facade for these plant areas / ventilation shafts should have adequate sound insulation properties to minimise the noise emanating through the building fabric.

6.2.8 Residual Impacts and Constraints on Future Receivers

The operational noise generated by the proposed railway can be properly mitigated by implementing the proposed mitigation measures. Residual noise impacts are not anticipated and there are no constraints on the future sensitive receivers that could be identified at this stage. In order to ensure compliance of the operational airborne noise impacts with the TM’s stipulated noise standard, the requirement for carrying out a noise commissioning test for all major fixed noise sources should be included in the Contract Document.

6.3 Conclusion

Potential noise sources and representative NSRs for the construction and operational phases have been identified. Noise prediction has been conducted based on established methodologies.

6.3.1 Construction Phase

Most of the construction activities will be conducted during daytime period except for the TBM launching shaft located to the south of WKN and the tunnel under Canton Road. The construction noise predictions have also included the potential noise contributions from concurrent projects.

Daytime

Noise assessment for daytime period reveals that mitigation measures including good site practice, use of quiet plant and site hoarding, installation of movable barriers for generally static plants would be required to alleviate the noise impacts at most of the sensitive receivers to within the statutory requirements.

However, the noise impacts at Canton Road Government School, Lai Chack Middle School, Man King Building, Man Fai Building and Olympian City Phase 3 would still be exposed to noise impacts exceeding the criteria. Further noise mitigation measures have therefore been investigated. Specific measures including the use of temporary noise barriers for some particular PMEs and sequential operation of construction activities at specific locations have been recommended to further reduce the noise impacts. However, there is still a minor noise exceedance (due to KSL only) of 4dB(A) for 2 months at the two schools and 2dB(A) for 4 months for Man King Building.

These residual noise impacts could be possibly mitigated by installing large full noise enclosure to accommodate all the noisy plant items. However, such a large-scale full enclosure in an urban setting like Canton Road or so near Man King Building would impose adverse visual impacts to the neighbouring receivers. The foundation works of the enclosure / large cantilevered noise barrier would require the use of piling rigs and the associated noise impacts on the Building would also be significant. In addition, the time required to construct such a large full noise enclosure would be comparable to the duration of noise exceedance. The net environmental benefits (in terms of construction noise impacts) of implementing this large full noise enclosure would not be significant. As such, it is not practicable to implement large noise enclosure for both the schools and Man King Building. The residual impacts on these receivers would be minor and temporary.

The noise exceedance at the two school, on the other hand, could possibly be avoided if the ground treatment work is scheduled to be carried out during the insensitive period, e.g. summer vacation. However, this mitigation measures will pose a constraint on the construction programme to the Contractor and thus prolonging the overall construction duration as well as nuisance to the schools. It is also considered that there may be supplementary classes or extra-curriculum activities during the school vacation and hence scheduling of the works may not be practicable. However, it is still recommended the Contractor to consult with the school representatives to confirm the practicality of scheduling such works to tie in with long school vacations and the arrangement of summer courses during this period.

Restricted Hours

The launching shaft will be provided with a noise insulating cover which will be closed during restricted hours to shelter the plant items and protect the residential premises in the vicinity. With the implementation of additional mitigation measures including quiet plant and enclosures etc, the predicted noise impacts during restricted hours would comply with the noise criteria. However, the Contractor shall take into account their specific construction methodology and apply separately for a Construction Noise Permit from the Noise Control Authority before commencement of works during restricted hours.

6.3.2 Operational Phase

Operational noise impacts can be effectively mitigated by implementing noise control treatment at source during the design stage and residual operational airborne noise impacts are not anticipated. The need for noise commissioning on fixed noise sources should be included in the Contract Document.

7. Groundborne Noise Impact Assessment

7.1 Construction Groundborne Noise

7.1.1 Legislation and Standards

Control over construction noise is governed by the Noise Control Ordinance (NCO), the EIAO, and their subsidiary requirements. Noise arising from general construction works during normal working hours is governed by the TM-EIAO under the EIAO as shown in Table 6-1. TM for the Assessment of Noise from Places other than Domestic Premises, Public Places or Construction Sites (TM-Places) under the NCO stipulates that noise transmitted primarily through the structural elements of building, or buildings, shall be 10 dB(A) less than the relevant ANLs. This approach to deriving groundborne noise limit is pragmatic given the temporary nature of the construction works and the practical difficulty to abate the inherently noise construction activities (e.g. rock drilling / breaking). Such approach is also being adopted in the Project Profile for Development of the Former Marine Police Headquarter (FMPHQ)^[7-4] for direct application of Environmental Permit.

Noise sensitivity of the HKCC (a performing arts centre) and the HKSM (a museum) is regarded as similar to schools where a completely immersed attention is often needed. Daytime groundborne construction noise criterion of 60dB(A) therefore applies with reference to TM-EIAO 70dB(A) criterion for schools and taking account of the minus 10dB(A) requirement under the NCO TM-Places. Following the same principle for groundborne noise criteria, groundborne construction noise levels inside hotel and domestic premises relying on open window for ventilation will be limited to 65dB(A), with reference to the daytime airborne noise criterion of 75dB(A) in accordance with TM-EIAO.

In the evening (1900 – 2300hrs) and during nighttime (2300 – 0700hrs), the TM on Noise from Construction Work other than Percussive Piling (TM-GW) applies. Again following the principle of deriving groundborne noise criteria, groundborne noise level will be limited to 10dB(A) below the respective ANLs for the Area Sensitivity Rating category of “B” at the NSRs along Salisbury Road and Canton Road. A summary of these criteria is given in Table 7-1 below.

Table 7-1 : Groundborne noise criteria for HKCC, HKSM, Schools, hotel guestrooms and domestic premises

	Groundborne Noise Criteria, dB(A) ^[2]
NSR Description	Daytime (except General Holidays & Sunday)	Daytime during general holidays and Sundays and all days during Evening (1900 to 2300 hrs)	Night-time (2300 to 0700 hrs)
HKCC - Grand Theatre, Studio Theatre, Concert Hall	60	55	[1]
HKSM - Planetarium, Recording Room	60	55	[1]
School - Classrooms	60/55 ^[4]	55	[1]
Hotel guestrooms along Canton Road & Salisbury Road	65	55	40
Domestic premises along Canton Road	65	55	40

[1] No sensitive uses during these periods

[2] Parameter for daytime noise is L_{eq, 30mins}

[3] Appendix 7-1 presents the ambient noise measurements in HKCC & HKSM

[4] A 5dB(A) reduction to the groundborne noise criterion is recommended for school during examination period.

The granting a CNP is subject to the relevant TMs issued under the NCO. A CNP may be revoked at any time for failure to comply with the permit conditions.

7.1.2 Noise Sensitive Receivers

NSRs that would be potentially affected by construction groundborne noise include the HKCC and HKSM, guestrooms of hotels along Salisbury Road and Canton Road, residential units along Canton Roads and schools to the north of Canton Road. The locations of these NSRs are illustrated in Figure 7-1.

The HKCC is a performance venue comprising Concert Hall, Grand Theatre, Studio Theatre, Exhibition Gallery and Foyer Exhibition Area, Rehearsal Rooms, Practice Rooms, Function Rooms, VIP Lounges. If needed, recording will be carried out during or after the performance in the recording facilities near the auditorium on 1/F. There will not be any operation during night-time and hence it is only a NSR during daytime and evening periods.

The HKSM is a museum comprising Activity Room and Maintenance office on basement, Lecture Hall, control room and Exhibition Hall on G/F, and Space Theatre, recording room and Office on 1/F. Sound recording is occasionally carried out in both the Lecture Hall (during live music performance) on G/F and the recording room on 1/F. There will not be any operation during night-time and hence it is only a NSR during daytime and evening periods.

Other sensitive receivers along Canton Road include hotel guestrooms and domestic premises. These NSRs would need to be taken into account during both the daytime and night-time periods. School classrooms are also noise sensitive during daytime period, and evening period if there are any evening classes. However, it is unlikely that there will be any class during the night-time period from 2300 to 0700 hours.

7.1.3 Groundborne Noise Sources from Construction Activities

Details of the construction methodologies, plant inventory and construction programme are given in Chapter 4 of this EIA report. Potential groundborne noise impacts on NSRs during the construction phase will arise mainly from hydraulic breakers, hand-held breakers, pipe pile rigs, rock drills and TBM. Other construction activities such as lorry movement, concreting, road paving etc are unlikely to generate significant groundborne noise. Airborne construction noise of these activities is addressed in Chapter 6 of this EIA Report.

It is anticipated that the rock breaking activities by large hydraulic breakers would represent the worst case for groundborne noise impact. Pipe pile rigs are required for the construction of pipe pile wall along Salisbury Road. These rigs will be operating in soil for most of the time until the last 0.5-1m during toe-in.

7.1.4 Groundborne Noise Prediction Methodology

The method used to predict construction groundborne noise is based on the U.S. Department of Transportation “High-Speed Ground Transportation Noise and Vibration Impact Assessment”, 1998^[7-1]. The vibration level L_v,rms at a distance R from the source is related to the vibration source level at a reference distance R_o. The conversion from vibration levels to groundborne noise levels is determined by the following factors:

C_dist: Distance attenuation

C_damping: Soil damping loss across the geological media

C_building: Coupling loss into building foundation

C_floor: Coupling loss per floor

C_noise: Conversion factor from floor vibration levels to noise levels

C_multi: Noise level increase due to multiple sources

C_cum: Cumulative effect due to neighbouring sites

The predicted groundborne noise level L_p inside the noise sensitive rooms is given by the following equation.

L_p = L_v,rms + C_dist + C_damping + C_building + C_floor + C_noise + C_multi + C_cum

7.1.4.1 Reference Vibration Sources

The reference source level was determined by on-site measurement of the rock breaking activities of a large hydraulic breaker operating in the basement level of the ERE station. The average vibration velocity measured at 5.5m from the hydraulic breaker was 0.298mm/s (rms). Similarly, the vibration velocities of handheld breakers, pipe pile rigs, rock drills and TBM were determined by measurements and some of these in Peak Particle Velocity (PPV). In such cases, a crest factor of four was applied to establish the rms level in accordance with the FTA Guidance Manual ^[7-1]. Appendix 7-1 presents the measurement records of these vibration sources.

The vibration measurements for the TBM were extracted from the in-situ measurements during the bored tunnelling of Kwai Tsing Tunnel of the West Rail project. The geology consists of mainly granite, which is considered similar to the geology along Canton Road. The measurements records are considered the most appropriate available information for the purpose of assessing TBM groundborne noise.

7.1.4.2 Soil Damping Loss

Internal losses of soil would cause the vibration amplitude to decay against the propagation distance and the decay relationship is based on the equation set out in the Transportation Noise Reference Book^[7-3]:

V(R) = V(R_o) ´ e^{-2pf h R/2c}.

The velocity amplitude V is dependent on the frequency f in Hz, the soil or rock loss factor h, the wave speed c in m/s, the distance R from the source to the NSR. The properties of soil materials are based on Ungar and Bender^[7-3] and reproduced in Table 7-2. The geological profiles along Salisbury Road are shown in Figure 7-2. No soil damping loss is applied when the NSR distance is less than the reference source level measurement distance.

Table 7-2 : Wave propagation properties of soils

Soil Type	Longitudinal Wave Speed c, m/s	Loss Factor, h	Density, g/cm^3
Rock	3500	0.01	2.65
Clay, clayey soil	1500	0.5	1.7

7.1.4.3 Coupling Loss into Building Structures

This represents the change in the incident ground-surface vibration due to the presence of the piled building foundation. The empirical values based on the guidance set out in the Transportation Noise Reference Book^[7-3] are given in Table 7-3.

Table 7-3 : Loss factor for coupling into building foundation

Frequency	Octave Band Frequencies, Hz
	16	31.5	63	125	250	500
Loss factor for coupling into building foundation, dB	-7	-7	-10	-13	-14	-14

7.1.4.4 Coupling Loss Per Floor

This represents the floor-to-floor vibration transmission attenuation. In multi-storey buildings, a common value for the attenuation of vibration from floor-to-floor is approximately 1dB attenuation in the upper floor regions at low frequencies and greater than 3dB attenuation at lower floors at high frequencies. Coupling loss of –1 dB reduction per floor is assumed for a conservative assessment.

7.1.4.5 Conversion from Floor Vibration to Noise Levels

Conversion from floor vibration levels to indoor reverberant noise levels is based on standard acoustic principles. The conversion factor is dependent on the surface area S of the room in m², the radiation efficiency s, the volume of the room V in m³ and the room reverberation time RT in seconds. Analyses were carried out for concert hall, theatres, lecture hall and recording studios. Results are summarised in Table 7-4.

Table 7-4 : Conversion factors from floor vibration levels to indoor reverberant noise levels

NSR Description	Conversion Cnoise (dB re 1x10^-6 mm/s)
HKCC & HKSM	–26 to –27
Hotel guestrooms and residential units	–26 to –27
School classrooms	-23

Note : Calculations of the above correction factors are given in Appendix 7-1

7.1.4.6 Multiple Vibration Sources

This represents the increase in noise level due to multiple noise sources. The groundborne noise levels from construction plant are summed logarithmically in accordance with standard acoustic principles to obtain the total groundborne noise level at the area of interest.

7.1.5 Assessment Results & Residual Impacts

Details of the construction methodologies, plant inventory and construction programme are given in Chapter 4 of this EIA report. Cut-&-cover tunnelling and mined tunnelling will be conducted under Salisbury Road and FMPHQ respectively. This tunnelling work will only be conducted during daytime. However, the bored tunnelling along Canton Road will be conducted 24 hours.

7.1.5.1 Cumulative Impacts

Discussions with the FMPHQ developer indicate that the key groundborne noise sources (e.g. foundation works) for the FMPHQ development would be completed in October 2004 and could even be completed by 2 to 3 months earlier. On the other hand, the construction of KSL will commence by early 2005. Most of the rock breaking activities along Salisbury Road would be started in April 2006 (see construction programme in Appendix 4-3). Hence, there will not be any overlapping of the rock breaking activities for KSL and FMPHQ redevelopment, and there will not be any cumulative groundborne noise impacts on HKCC and HKSM, and other sensitive receivers along Canton Road.

7.1.5.2 Tunnelling Work Under Salisbury Road and FMPHQ

The tunnel construction along Salisbury Road will be mostly above the rockhead until it approaches the YMCA. Tunnel sections close to the HKSM would therefore be on soft ground. At the tunnel sections between YMCA and Old Fire Station Building (OFSB), hydraulic breakers and pipe pile rigs would be operating on rock from below –5mPD. For the cut-&-cover tunnelling to be carried out for the section along Salisbury Road, pipe pile walls will be used as temporary walls for excavation. For each section of work, pipe pile walls will be first installed down to the bottom of the tunnel levels. After the installation of the pipe pile walls, excavation will then be conducted layer by layer with temporary props installed accordingly, until the entire excavation process is completed. Hence, the toeing in of the pipe piles (ie one of the dominant groundborne noise sources) will not overlap with the use of hydraulic breakers during the excavation process.

The predicted maximum groundborne noise levels at the HKCC, HKSM and YMCA are given in Table 7-5. Sample calculations are given in Appendix 7-2. All the predicted noise impacts due to rock breaking are below the statutory criteria given in Section 7.1 and there are no residual construction groundborne noise impacts.

Table 7-5 : Predicted maximum construction groundborne noise levels at HKCC HKSM and YMCA

NSR Description	Soil Materials [2]	Area	Max Predicted Noise Level, dB(A)	Exceedance above ground-borne noise criteria of 60 dB(A)
FMPHQ – Construction plant in simultaneous operation
Hong Kong Space Museum [1]	Marine deposit/alluvium/fill	1/F Recording Studio 1/F Space Theatre	<15 <15	0 0
Hong Kong Cultural Centre	Granite	Grand Theatre Concert Hall Studio Theatre	20 25 33	0 0 0
YMCA	Granite	Guestrooms	33	0
Salisbury Road between KPD to Hankow Road – Construction plant in simultaneous operation
Hong Kong Space Museum [1]	Marine deposit/alluvium/fill	1/F Recording Studio 1/F Space Theatre	<15 <15	0 0
Hong Kong Cultural Centre	Granite	Grand Theatre Concert Hall Studio Theatre	16 19 30	0 0 0
YMCA	Granite	Guestrooms	37	0
Both FMPHQ and Salisbury Road between KPD to Hankow Road – Construction plant in simultaneous operation
Hong Kong Space Museum [1]	Marine deposit/alluvium/fill	1/F Recording Studio 1/F Space Theatre	<15 <15	0 0
Hong Kong Cultural Centre	Granite	Grand Theatre Concert Hall Studio Theatre	21 26 35	0 0 0
YMCA	Granite	Guestrooms	38	0

Notes:

[1] Tunnel section along HKSM is above the inferred rockhead level.

[2] Soil materials refer to materials being impacted by construction plant on site.

7.1.5.3 Pipe Piling Along Salisbury Road

Pipe pile rigs are required for the construction of pipe pile walls along Salisbury Road. These rigs will be operating in soil for most of the time until the last 0.5-1m during toe-in.

The predicted groundborne noise with pipe pile rigs working in fill materials would be less than 19dB(A) for HKCC. During toe-in, the predicted noise level for the Studio Theatre in HKCC would be 31dB(A). For YMCA, which is the nearest hotel along Salisbury Road, the predicted groundborne noise is 38dB(A) when pipe pile rigs are operating at rock (see Appendix 7-2 for calculations). These impacts would comply with the statutory noise criteria as described in Section 7.1.

7.1.5.4 Bored Tunnelling Along Canton Road

The tunnel boring machine will be at least 150m away from HKCC and 270m away from HKSM. The predicted groundborne noise levels are less than 15dB(A) and are well below the adopted groundborne noise criteria. Adverse groundborne noise impact due to bored tunnelling on HKCC and HKSM is not anticipated.

Along Canton Road, the predicted groundborne noise levels for the hotels and domestic premises are not greater than 33dB(A) and for the school is 43dB(A). They are below their respective groundborne noise criteria. There are no residual impacts and hence mitigation measures are not required.

The detailed analyses are given in Appendix 7-2.

7.1.6 Recommendations

Prediction of construction groundborne noise indicates the criteria will be achieved and mitigation measures are not required. In order to ensure proper control of groundborne noise is executed by the contractor, a monitoring requirement is recommended at the worksites in front of the HKCC and HKSM for assurance checking. Rock breaking activities will be subject to an assurance groundborne noise measurement at one selected location each inside HKCC and HKSM to be agreed with their respective operators. If groundborne noise criterion is exceeded, the monitoring shall continue daily until acceptance has been restored against the criterion. Otherwise the monitoring can be discontinued.

7.2 Operational Groundborne Noise

7.2.1 Legislation and Standards

With reference to the Technical Memorandum for the Assessment of Noise from Places Other Than Domestic Premises, Public Places or Construction Sites (TM-Places) under the Noise Control Ordinance (NCO), 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). These criteria apply to all kinds of use from domestic premises to performing arts centres. According to the TM-Places, the groundborne noise standard for HKCC and HKSM is L_{eq 30mins} 55dB(A) during general operational periods. Given the nature of activities held at HKCC and HKSM, it is desirable that a more stringent design goal be adopted for these facilities.

Under Annex 13 of the TM-EIA performing arts centres are defined as potential Noise Sensitive Receivers (NSRs). However, the TM-EIA does not have any specific criteria for groundborne noise at performing arts centres. As such the criteria for evaluating noise impacts on these facilities shall be determined on a case by case basis in accordance with the TM-EIA Annex 5. A groundborne noise limit of Lmax 25dB(A) is proposed by the project proponent and subsequently agreed by the EIAO Authority for special buildings, such as concert halls and recording studios following a recognised international standard - the latest guidance manual “Transit Noise and Vibration Impact Assessment” 1995 issued by the Federal Transit Administration (FTA), US Department of Transportation.

The operational groundborne noise criteria for the representative NSRs along KSL alignment are tabulated in Table 7-6 below.

Table 7-6 : Operational groundborne noise criteria for HKCC, HKSM, Schools, hotel guestrooms and domestic premises

	Groundborne Noise Criteria, dB(A)
NSR Description	Day & Evening (0700 to 2300 hrs)	Night (2300 to 0700 hrs)
HKCC - Grand Theatre, Studio Theatre, Concert Hall	25 (Lmax)	-
HKSM - Planetarium, Recording Room	25 (Lmax)	-
School – Classrooms	55 (Leq 30 mins)	-
Hotel guestrooms along Canton Road & Salisbury Road	55 (Leq 30 mins)	45 (Leq 30 mins)
Domestic premises along Canton Road	55 (Leq 30 mins)	45 (Leq 30 mins)

Note: For HKSM and HKCC, the 25dB(A) criterion is based on FTA guidance manual. It is maximum rms average over a 1 second period.

7.2.2 Noise Sensitive Receivers

The most sensitive receivers along the KSL alignment are primarily the HKCC, with three performing venues (the Grand Theatre, the Concert Hall and the Studio Theatre) and the HKSM, with the planetarium and the recording room. The HKCC has frequent performances that are held in its three venues and sometimes these facilities are used for digital sound recording. The HKSM Planetarium is also used for public performances and the facility routinely undertakes digital sound recording and editing of its presentation materials in the recording room.

Other sensitive receivers along the KSL alignment include schools, hotel guestrooms and domestic premises. Hotels and domestic premises are taken into account during both the daytime and night-time periods. HKCC, HKSM & school classrooms are considered to be noise sensitive during daytime and evening only.

Some of these structures have large underground foundation walls facing the alignment, with occupied levels at the same depth as or deeper than the KSL tunnels. The information pertaining to the sensitive receivers and the proposed ambient noise criteria are shown in Appendix 7-3. The locations of these representative groundborne noise sensitive receivers are shown in Figures 7-3-1 to 7-3-4.

7.2.3 Groundborne Noise Sources from Operation

When trains operate in tunnels that are located in close proximity to occupied structures, there is a possibility that vibrations associated with train passbys will be transmitted through the ground and structure, and be radiated as noise in the occupied spaces within the structure. The noise and vibration levels within the structure may be high enough to cause annoyance to the NSRs.

7.2.4 Groundborne Noise Prediction Methodology

The most current and evolved projection methodology recommended by the FTA Manual ^[7-5] is used in this EIA study. This manual is issued by the US Department of Transportation in 1995 and is intended to provide guidance in preparing and reviewing the noise and vibrations sections of environmental submittals to the US Government for grant applications. The methodology has been applied on a number of transit systems over the years, including West Rail, East Rail Tsim Sha Tsui Extension, and MTR Tseung Kwan O Line.

The basic equation describing the model, in decibels, is

L = FDL + LSR + TIL + TCF + CCF + BCF + BVR + CTN + SAF,

Where the prediction components are:

L: Ground borne vibration or noise level within the structure, re: 1 m-in/sec or 20 m-Pascal

FDL: Force density level for the KCR SP1900 EMU, re: 1 lb/in^0.5

LSR: Unit force incoherent line source response for the ground, re: 1 m-in/sec

TIL: Trackform attenuation or insertion loss, relative level

TCF: Vibration coupling between the tunnel and the ground for soil based tunnels, relative level

CCF: Points and crossing correction factor, relative level

BCF: Vibration coupling loss factor between the soil and the foundation, relative level

BVR: Building vibration reduction or amplification within a structure from the foundation to the occupied areas, relative level

CTN: Conversion from floor and wall vibration to noise, 1 m-in/sec to 20 m-Pascal

SAF: Safety margin to account for wheel/rail condition and projection uncertainties

The units selected for the vibration analysis (re: 10^-6 in/sec) allow direct numerical comparison of vibration levels and noise levels (re: 20*10^-6 Pa) for structure borne noise, which is considered very advantageous. Units for the FDL are consistent with the English units system and thus simplify the analysis and debugging processes and hence minimise the calculation errors. These are also the units used in the FTA Manual.

Predictions are in most cases based on assuming the closest distance from the track centreline to the building foundation of the receiver; however, if a particular facility within a structure is the sensitive receiver, the setback distance is assumed to be from the track centreline to the closest part of the affected receivers. Where curved track occurs the track is considered to be straight and perpendicular to the closest setback point of the venue or receiver. For receivers located outside the curve such as HKCC, this assumption is clearly conservative.

Projections of groundborne noise levels are compared to relevant noise criteria for different trackform options. Using these comparisons, trackform specification is assessed and design recommendations made, as necessary, so that there will be no adverse impact caused by groundborne noise. The key components of the model are described below and the correction factors adopted in this study are summarised in Appendix 7-3.

7.2.4.1 Force Density Level (FDL)

The vibration source strength level (Force Density Level) for train operations on the KSL was derived from wayside vibration measurements taken during SP1900 seven car EMU passbys on ballast and sleeper track up track main line at Pat Heung Depot. This is the same type of EMU that will be in operation on KSL. The duration of one passby is the period between the passage of the front and rear ends of the train pasts the closest point on the alignment to the building foundation. Measurement results of the FDL are shown in Appendix 7-3.

7.2.4.2 Line Source Response (LSR)

The basic quantity required for the determination of LSR is the vibration response caused by a unit point source impact, which is defined as the Point Source Response (PSR). Given the PSR along the alignment over the length of the train, the LSR follows directly by incoherent integration of the PSR over the length of the train. Vibration propagation characteristic, in terms of PSR & LSR, is established by vibration measurements conducted from December 2002 to March 2003 at locations along the Salisbury Road and lower Canton Road. The vibration measurement results are shown in Appendix 7-3.

7.2.4.3 Trackform Insertion Loss (TIL)

The attenuation performance of existing trackforms on West Rail was measured in 2002 and 2003 with attenuation curves given in Appendix 7-3. Low vibration trackform (LVT) or resilient baseplates installed atop concrete embedded sleepers (referred to as trackform Type 1 herein) and the tunnel variant of the floating slab trackform (FST2, referred to as trackform Type 2 herein) are already installed on West Rail (WR) and the Ma On Shan (MOS) Extension. Both trackforms have demonstrated attenuation performance for groundborne noise impacts adjacent NSRs. These attenuations are assumed in this study.

In addition, two variants of the KCRC tunnel FST are being developed for KSL. The first FST variant, referred to as trackform Type 3, has altered support bearings to provide greater attenuation at higher frequencies. The existing KCRC tunnel FST has support bearings that are manufactured as solid rubber. However, the thickness of the bearings allows short wavelength vibration to pass through the bearing more easily at high frequencies, above 160 Hz, as shown in Appendix 7-3, thus reducing attenuation at higher frequencies. High frequency attenuation can thus be improved by reduction of the bearing thickness, which moves the passing phenomenon to a higher frequency range. New bearings are proposed which reduce the effective thickness of the bearing by introduction of steel of internal flat plates, thus creating a layered bearing, whilst preserving the civil performance of the bearing, namely sufficient resistance to static and low frequency dynamic train loading.

The second FST variant, referred to as trackform Type 4, has both altered support bearings as in trackform Type 3, and increased mass of the FST slab to lower the resonance frequency of the FST from 12.5 Hz, the resonance frequency of the KCRC tunnel FST, to 10 Hz, providing greater attenuation in the lower frequency range. The projected attenuations for these FST variants are given in Appendix 7-3. Despite the use of a combination of trackforms, there will be no jointed track used in KSL.

7.2.4.4 Conservatism in the Model Prediction

An attempt has been made to estimate the other components of the prediction as accurately as possible, neither underestimating nor overestimating their effect. Thus, the prediction conservatism is primarily determined by the 10 dB safety factor and the use of an FDL determined on rail whose rough condition is not representative of expected operational conditions. The conservatism built into the predictions is thus on the order of 15 dB.

Force Density Level

The FDL determined for the SP1900 EMU was obtained from passby measurements on the up track through Pat Heung Depot on rough rail, which during normal operations will be maintained to a much smoother level. Comparisons of the FDL obtained for the SP1900 EMU to other Hong Kong transit trains, including the old East Rail EMU, as well as several other heavy rail EMUs in operation in the United States, indicate that the SP1900 FDL is 5 dB to 10 dB higher than the maximum FDL levels for the other trains considered above 20 Hz, the low frequency threshold of hearing. A comparison of FDLs is shown in Appendix 7-3.

Ground Vibration Transmission

In most ground borne noise assessments, and usually on account of a lack of measurement data, only the most rudimentary aspects of the propagation of vibration through the ground from the tunnel to the structure are taken into account. In this study, considerable care was taken in quantifying the six possible paths through the soil, the rock and along the rock interface that vibration can take from the tunnel to the structure, as shown in Appendix 7-3. It is then assumed that vibration propagates to the structure along all relevant paths and the vibration impact on the structure is determined as the energetic sum of vibration following all relevant paths, thus necessarily resulting in predictions that are conservative in nature.

Safety Factor

Even though it is not required by the FTA Manual, a safety factor of 10 dB is also added to the predictions. This factor accounts for variability in prediction and unforeseen factors related to wheel and rail maintenance. The projection with a safety factor of 10 dB added provides, essentially, an upper bound on selected measured vibration data taken on other systems under similar circumstances.

Train Passbys

Simultaneous passbys are assumed to occur adjacent to every sensitive receiver. This clearly will not occur at every receiver, nor will it necessarily always occur at any one particular receiver. Thus, where one single train passbys occur, groundborne noise impacts are overestimated on the order of 2 dB.

Independent review and verification

A measurement study of the groundborne noise impact on the Kwai Tsing Theatre by the operation of the West Rail (SP1900 EMU and FST Type 2 installed) was conducted. The measurement results were compared with the prediction made using the same groundborne noise assessment methodology for the KSL to allow verification of the prediction accuracy. The measurement results indicated that structural borne noise level during train passbys was roughly 2dB(A) and that there was close agreement between the measured vibration levels and the projection.

The KSL groundborne noise predictions and the measurement results at Kwai Tsing Theatre have been reviewed by the original author of the FTA Manual. The reviewer confirmed that the assessment was based on a very thorough analysis using internationally recognised, state-of-the art methods, and that the conservatism built into the predictions was in the order of 15-20dB. The independent review report and the Kwai Tsing Theatre measurements results are shown in Appendix 7-3.

7.2.5 Prediction Results

The predicted operational groundborne noise results are summarised in Table 7-7 and sample detailed calculations are shown in Appendix 7-3.

Table 7-7: Predicted operational groundborne noise levels

NSR	Description	Location	Track Type		Criteria	Prediction dB(A)
			Up	Down	dB(A)	Lmax	Leq (30min)	Leq (24h)
GN1	Sheraton Hotel	4/F Guestroom	2	2	45	<35	<35	<35
GN2	Peninsula Hotel	2/F Guestroom	4	4	45	<35	<35	<35
GN3	HKSM	Planetarium	4	4	25	<15	<15	<15
GN4		Recording Room	4	4	25	<15	<15	<15
GN5	YMCA Hotel	4/F Guestroom	4	4	45	<35	<35	<35
GN6	HKCC	Grand Theatre	4	4	25	<15	<15	<15
GN7		Concert Hall	4	4	25	<15	<15	<15
GN8		Studio Theatre	4	4	25	<15	<15	<15
GN9	Redeveloped FMPHQ	G/F Guestroom	2	2	45	37	<35	<35
GN10	Marco Polo Hong Kong Hotel	2/F Guestroom	2	2	45	<35	<35	<35
GN11	No. 2-16 Canton Road	1/F Residential	2	2	45	<35	<35	<35
GN12	Imperial Building	1/F Residential	2	2	45	<35	<35	<35
GN13	Marco Polo Prince Hotel & Gateway Hotel	2/F Guestroom	2	2	45	41	37	36
GN14	Canton Road Government School	1/F Classroom	2	2	55	<45	<45	<45
GN15	FSD Kowloon South Divisional HQ	3/F Residential	2	2	45	<35	<35	<35
GN16	R(A) Future development	1/F Residential	2	2	45	<35	<35	<35
GN17	West Kowloon Station Potential Topside Development	1/F Residential	2	2	45	<35	<35	<35
GN18	Man King Building	1/F Residential	1	1	45	36	<35	<35
GN19	Charming Garden	2/F Residential	1	1	45	<35	<35	<35
GN20	Park Avenue	5/F Residential	1	1	45	<35	<35	<35
GN21	Olympian City – Phase 3	2/F Residential	2	2	45	<35	<35	<35
Note:
1.	Track Type 1 = Resilient baseplate, Type 2 = 12.5Hz FST (Plain Bearing), Type 3 = 12.5 Hz Modified FST, Type 4 = 10 Hz Modified FST
2.	Prediction is based on Leq(double passbys) i.e. simultaneous passbys of up and down trains.
3.	Calculations are based on 9-car train scenario.
4.	Leq(30mins) and Leq(24hrs) are based on maximum target frequency of 34 trains per hour in each direction running for 19 hours daily. The predictions represent the worst case of the day i.e. constant levels during the day and at night, and extended operation hours. It should be noted that with the reduced patronage forecast, the maximum number of trains per hour will unlikely exceed 25 within the next 30 years.
5.	Noise levels of 10 dB(A) below the criteria (i.e. 15, 35 or 45 dB(A)) are considered to be physically insignificant as compared to the relevant criteria.
6.	For HKSM and HKCC (GN 3,4,6,7,8), the 25dB(A) criterion is based on FTA guidance manual. It is maximum rms average over a 1 second period. Other criteria are in Leq 30min for worst case scenario as shown in Table 7-6.

7.2.6 Cumulative Impacts from the Existing MTR Tsuen Wan Line and Other Worst Case Scenarios

The MTR Tseun Wan Line tunnel at the juncture of Nathan and Salisbury road is situated in rock and significantly deeper than the KCRC KSL extension, which is in soil just above the rock head near where it crosses over the MTR tunnels at this road intersection. Vibration waves radiating from the KSL tunnel are thus trapped in the soil layer above the rock and propagate with two-dimensional geometric attenuation, as against three-dimensional geometric attenuation for the MTR tunnel in bedrock. Furthermore, MTR trains passing by the Space Museum planetarium during two separate noise measurements were not audible. Thus, groundborne vibration and noise from the MTR tunnels is not expected to add significantly to the levels resulting from KSL train operation.

There will be no freight traffic, only EMU, running on KSL. Because of the slow speed of work trains, and the fact that work trains have primary suspensions installed with low resonance frequencies and have a short length, it is not expected that the resulting groundborne noise and vibration would exceed that of a revenue EMU under the anticipated operational conditions. In addition, work trains will only be operated after revenue operation at night. There will be no impact to the critical sensitive receivers such as HKCC, HKSM and school classrooms as these are not considered to be noise sensitive during nighttime.

7.2.7 Recommendations

The four types of trackforms should be installed in accordance with the locations described in Table 7-8 and in Figure 7-4.

Table 7-8: Summary of Recommended Track Type

From	To	Approximate Extent (m)	Track Type
ETS Overrun Tunnel	New World Subway No.1	130	2
New World Subway No.1	Nathan Road	40	3
Nathan Road	Kowloon Park Drive Subway	180	4
Kowloon Park Drive Subway	FMPHQ	50	3
FMPHQ	Jordan Road	1350	2
Jordan Road	Olympian City Phase 3	1630	1
Olympian City Phase 3	Hoi Fai Road	240	2
Hoi Fai Road	NAC Overrun Tunnel	180	1

In order to ensure compliance of the operational groundborne noise criteria, a commissioning test will be included in the Contract document. More frequent rail and train maintenance, and adjustment of speed profile at critical locations such as Salisbury Road in front of HKCC and HKSM will be able to further reduce the groundborne noise impacts as contingency measures.

7.3 Conclusion

7.3.1 Construction Phase

Potential groundborne noise sources during the construction phase have been identified. The noise impacts on neighbouring sensitive receivers have been quantified. Results indicate that the predicted impacts are within the statutory requirements and hence mitigation measures are not required. There are no residual construction groundborne noise impacts.

7.3.2 Operational Phase

Projections of ground borne noise at identified representative sensitive receivers have been performed, based on a methodology recommended by the US Department of Transportation and assuming an additional 10 dB safety factor, using train source vibration levels measured on the KCRC SP1900 EMU, ground vibration propagation measurements performed along lower Canton and Salisbury Roads and trackform attenuation data taken on West Rail.

In addition to the two trackforms already in use in WR and MOS Extension, two variant FST trackforms are proposed to provide extra attenuation required at the LCSD facilities. These variants are incrementally altered version of the existing KCRC tunnel FST: they both have modified support bearings and one has increased slab mass in order to lower the resonance frequency from 12.5 Hz to 10 Hz. With the installation of the recommended trackforms, no exceedance has been identified at any NSRs along KSL.

8. Water Quality Impact Assessment

8.1 Legislation and Standards

The relevant legislation and associated guidance applicable to the present study for the assessment of water quality impacts include:

· Water Pollution Control Ordinance (WPCO) CAP 358, Water Quality Objectives (WQOs) for the Victoria Harbour Water Control Zone (VHWCZ) ^[8-1];

· Technical Memorandum for Effluents Discharged into Drainage and Sewerage Systems Inland and Coastal Waters (TM-Water), Effluents discharge limits for the Victoria Harbour Water Control Zone^[8-2];

· Environmental Impact Assessment Ordinance (EIAO) (Cap. 499), Technical Memorandum on Environmental Impact Assessment Process (TM-EIA) ^[8-3];

· ProPECC PN 5/93 “Drainage Plan subject to Comment by the Environmental Protection Department” ^[8-4];

· ProPECC PN 1/94 “Construction Site Drainage” ^[8-5];

· ProPECC PN 3/94 “Contaminated Land Assessment And Remediation” ^[8-6]; and

· “Recommended Pollution Control Clauses for Construction Contracts” issued by EPD^[8-7].

8.2 Baseline Conditions

8.2.1 Victoria Harbour

Victoria Harbour is a major tidal channel with considerable assimilative capacity. According to Marine Water Quality 2002^[8-8], with the implementation of the Harbour Area Treatment Scheme (HATS) Stage 1, the water quality in eastern end and middle portion of the Victoria Harbour has been improved. Although the discharge volume from the Stonecutter Island Sewage Treatment Works is high, the overall water quality in western harbour is still maintained.

8.2.2 Monitoring Stations Near to Project Site

The representative marine water quality monitoring stations in the vicinity of the project site are VT10 in YMT Typhoon Shelter, and VM5, VM6, and VM7 in the Victoria Harbour. A summary of the monitoring data at these stations as shown in Marine Water Quality Year 2002 is given in Table 8-1:

Table 8-1 : Marine water quality in Year 2002

	Monitoring Station
	VM5	VM6	VM7	VT10 (Yau Ma Tei Typhoon Shelter)
Temperature (°C)	23.1 (16.3 – 27.4)	23.1 (16.3 –27.4)	23.2 (16.4 – 27.5)	24.0 (18.2 – 27.6)
Salinity (ppt)	31.8 (29.1 –33.3)	31.8 (28.7 – 33.2)	31.7 (28.7 – 33.2)	30.5 (27.3 – 32.1)
Dissolved Oxygen (mg/L)	5.7 (4.6 –6.9)	5.5 (4.7 – 6.3)	5.6 (4.6 – 7.0)	3.1 (1.9 – 3.9)
BOD5 (mg/L)	1.2 (0.5 – 2.4)	1.2 (0.7 –2.3)	1.5 (0.5 – 3.1)	1.1 (0.8 – 1.7)
SS (mg/L)	6.0 (3.2 – 13.3)	7.0 (3.4 – 17.0)	6.0 (3.9 – 10.1)	14.8 (4.8 – 26.3)
TIN (mg/L)	0.31 (0.13 – 0.64)	0.33 (0.20 – 0.65)	0.34 (0.20- 0.66)	0.54 (0.38 – 0.71)
NH3-N (mg/L)	0.006 (0.003 – 0.010)	0.006 (0.003 – 0.010)	0.007 (0.003 – 0.011)	0.009 (0.004 – 0.013)
ChlorophyII-a (mg/L)	4.8 (0.6 – 18.9)	4.2 (0.4 – 16.2)	4.2 (0.7 –19.8)	1.5 (0.7 – 4.5)
E. Coli (cfu 100m/L)	4500 (630 – 42000)	5000 (600 – 19000)	4600 (1500 – 60000)	3700 (330 –37000)

Note: [1] Data presented are depth averaged, except as specified.

[2] Data presented are annual arithmetic mean except for E. Coli, which are geometric mean values

[3] Data enclosed in brackets indicate the ranges

[4] Bolded cells indicate non-compliance with the WQOs for a parameter

According to Marine Water Quality 2002, most monitoring stations showed a reduction of E. Coli and NH₄ – N on comparing with past few years. The DO in Victoria Harbour has reached a high value in 2002. Widespread increases in DO at most monitoring stations in Victoria Harbour were observed. According to EPD’s past marine water quality monitoring data, there was an overall rise of about 1°C in the surface and depth-averaged temperature over the past ten years. It is probably related to the extensive uses of seawater as coolant in the harbour area.

It can be seen from the above table that the water quality in YMT Typhoon Shelter (VT10) was not satisfactory. It is signified by low DO, high TIN and high faecal bacteria. Non-compliance of DO and Total Inorganic Nitrogen (TIN) were also recorded in Year 2002.

8.3 Water Sensitive Receivers

The closest water receiving body in the vicinity of the project site is the western region of the VHWCZ. Part of the alignment will also be adjacent to the YMT Typhoon Shelter. Due to the highly urbanised nature of Kowloon Peninsula, there are no natural streams located within 300m from the alignment.

There is neither marine biological sensitive receiver such as fish culture zone, shellfish culture ground, marine park/reserve nor commercial fishing ground in the VHWCZ. However, a number of seawater abstraction points for flushing and cooling are identified in the vicinity.

The representative Water Sensitive Receivers (WSRs) in the vicinity of the project site are summarized in Table 8-2 and shown in Figure 8-1.

Table 8-2 : Water sensitive receivers

WSR no.	WSRs Description	Operator
1	Yau Ma Tei Typhoon Shelter	-
2	Seawater abstraction point (Flushing)	WSD
3	Seawater abstraction point (Cooling)	MTRC Kowloon Station
4	Seawater abstraction point (Cooling)	China H.K City
5	Seawater abstraction point (Cooling)	Harbour City
6	Seawater abstraction point (Cooling)	Ocean Centre
7	Seawater abstraction points (Cooling)	Ocean Terminal
8	Seawater abstraction points (Cooling)	Government premises
9	Seawater abstraction points (Cooling)	New World Centre
10	Planned Seawater abstraction points (Cooling)	East Rail Extension
11	Storm water outfall	DSD
12	Storm water outfall	DSD

8.4 Construction Water Quality Impact

The site will be maintained by good site practices and there will be no direct discharge of wastewater into the Victoria Harbour during the construction phase. Hence, quantitative water quality dispersion modelling is considered not necessary. Other water quality issues relevant to the construction phase are described in the following sections.

8.4.1 Pollution Sources from Construction Activities

According to the latest design information, there will be no dredging activities, marine work platform construction and reclamation work for the proposed barging facility. Potential water pollution sources during construction phase will include sources mainly from land-based activities, including:

· Construction runoff;

· Runoff from tunnelling activities and underground works;

· Sewage effluent due to workforce on site;

· Drainage diversion;

· Groundwater seepage; and

· Groundwater from potential decontamination activities

8.4.1.1 Construction Runoff

Construction site runoff comprises:

· Runoff and erosion from site surfaces, drainage channels, earth working areas and stockpiles;

· Runoff from the proposed barging facility;

· Wash water from dust suppression sprays and wheel washing facilities; and

· Fuel, oil, solvents and lubricants from maintenance of construction machinery and equipment.

Construction runoff may cause physical, biological and chemical effects. The physical effects include potential blockage of drainage channels and increase of Suspended Solid (SS) levels in the VHWCZ.

Local flooding may also occur in heavy rainfall situations. The chemical and biological effects caused by the construction runoff are highly dependent upon its chemical and nutrient content.

Runoff containing significant amounts of concrete and cement-derived material may cause primary chemical effects such as increasing turbidity and discoloration, elevation in pH, and accretion of solids. A number of secondary effects may also result in toxic effects to water biota due to elevated pH values, and reduced decay rates of faecal micro-organisms and photosynthetic rate due to the decreased light penetration.

8.4.1.2 Tunnelling and Underground Works

During tunnelling work, rainfall, surface runoff and groundwater seepage pumped out from the tunnel would have high SS content. The situation would be worse during wet seasons.

Surface runoff may also be contaminated by bentonite and grouting chemicals that would be required for the construction of bored tunnels (for tunnel boring and ground treatment) and diaphragm walls for cut-and-cover tunnel sections. In addition, wastewater from tunnelling works will also contain a high concentration of SS.

8.4.1.3 Sewage Effluent

Sewage effluents will arise from the sanitary facilities provided for the on-site construction workforce. The characteristics of sewage would include high levels of BOD₅, Ammonia and E. Coli counts.

8.4.1.4 Drainage Diversion

Drainage infrastructure is available along the proposed alignment from TST to NAC. A separate Drainage Impact Assessment will be prepared and submitted by the Design Team. The assessment will identify the diversion or upgrading of the existing drainage infrastructure. The potential water quality impact associated with the drainage diversion or upgrading will be from the run-off and erosion from site surfaces and earth working areas. Small amount of wastewater may be released during the disconnection of various drainage systems.

8.4.1.5 Groundwater Seepage

The WKN and the tunnels from WKN to NAC will be constructed by cut and cover using D-wall technique (see Chapter 4). This construction methodology can minimise the intrusion of groundwater during excavation. D-wall technique involves excavation of a narrow trench that is kept full of slurry, which exerts hydraulic pressure against the trench walls and acts as a shoring to prevent collapse. Slurry trench excavations can be performed in all types of soil, even below the ground water table.

The construction usually begins with the excavation of discontinuous primary panels of typically up to 6m long and down to the rockhead. In order to provide an effective cut-off to ground water flow, the walls will need to be toe grouted. Once the excavation of a panel is completed, a steel reinforcement cage will be placed in the centre of the panel. Concrete is then poured in one continuous operation. Once the primary panels are set, secondary panels will be constructed between the primary panels and the process then repeats to create a continuous wall. It should be noted that this slurry trench method will reduce the gap between the panels to the practicable minimum. After this, soil excavation will be commenced. The intrusion of groundwater through D-wall panels during soil excavation is therefore considered insignificant.

For the tunnels to the south of WKN, bored tunnelling will be adopted along Canton Road, except for some locations (e.g. TBM launching / construction access shaft, CRPB, tunnel section along Salisbury Road, etc as described in Chapter 4) which will be constructed by cut-&-cover. Ground treatment (e.g. grouting) will be carried out along Canton Road prior to bored tunnelling. The intrusion of groundwater during bored tunnelling would therefore be insignificant.

8.4.1.6 Groundwater from Contaminated Area

Potential land contamination areas are identified in the vicinity of the study area including the TST Fire Station, the former shipyard sites within the West Kowloon Reclamation, Canton Road Government Office, Tai Kok Tsui petrol filling station at Skyway House and the factory building at Shum Mong Road.

Site investigations were conducted between Oct 2002 and Feb 2003. Ground water table was found at about 1-2m below the ground level. The locations of the collected groundwater samples are shown in Figure 8-2. Some of the water samples show certain degree of contamination as described in the following sections.

(a) Groundwater Analytical Results

Table 8-3 shows the measurement results for the groundwater samples taken from 5 drillholes. Heavy metals (including Cd, Cr, Cu, Ni, Pb, Zn, Hg, As, Ba, Co, Mo and Sn), BTEX, cyanide, PAH, Total Petroleum Hydrocarbon (TPH) and dioxin were tested.

Estimation indicates that the amount of groundwater generated during dewatering will be around 580m³ per day, which is corresponding to the flow band of 400 – 600m³ / day listed in the TM-Water.

Table 8-3 : Comparison between contaminants and TM-Water effluent discharge criteria

Parameters	Maximum Concentration^[1](mg/L) (unless specified)					TM-Water Effluent limit for inshore waters of VHWCZ (mg/L)	Reporting Limit (mg/L)^[5]
	KSD100/DHE063	KSD100/DHEPZ052	KSD100/DHEPZ113	KSD100/DHE053	KSD100/DHE120^[3]	400 – 600 m^3 / day
PH	7.89	8	7.4	7.2	7.7	6-9
Temperature °C	22.4	20.4	19.1	19.8	26.9	< 40°C
TPH C6 – C9	<0.020	<0.020	<0.020	<0.020	<0.020	---
TPH C10–C14	<0.050	<0.050	<0.050	<0.050	<0.050	---	20 –25
TPH C15 – C28	0.115	<0.1	0.13	<0.1	0.11	---
TPH C29 – C36	<0.050	<0.050	<0.050	<0.050	0.321	---
Dioxin (pg/L)	0.04	---	---	---	0.019	---	10 pgL
Cd	< 0.0002	0.0013	0.0005	<0.0002	0.0005	0.001
Cr	0.006	0.043	0.051	0.0071	0.0043	0.7
Cu	0.4	0.230	0.330	0.340	0.055	0.7
Ni	0.0035	0.023	0.027	0.0057	0.0081	0.7
Pb	0.013	0.210	0.210	0.0051	0.061	0.7
Zn	0.130	0.270	0.29	0.053	0.037	0.7
Hg	< 0.0005	0.0016	0.0029	0.0025	<0.0005	0.001
As	<0.010	0.021	0.015	<0.010	<0.010	0.7
Ba	0.130	0.35	0.35	0.110	0.120	2.7
Co	0.0045	0.016	0.017	0.0048	<0.001	---
Mo	0.015	0.019	0.017	0.026	0.0079	---
Sn	0.0053	0.124	0.074	0.0074	0.011	---
Total Cyanide (mg/L)	< 0.05	< 0.05	< 0.05	< 0.05	< 0.05	---
PAH^[8] (mg/L)	< 0.5	< 0.5	< 0.5	< 0.5	< 0.5	---	0.1 – 1 (Low molecular weight) 0.02 – 0.1 (High molecular weight)
Benzene (mg/L)	< 2	< 2	< 2	< 2	< 2	---
Ethylbenzene (mg/L)	< 2	< 2	< 2	< 2	< 2	---
Toluene (mg/L)	< 2	< 2	< 2	< 2	< 2	---	1
Meta- & Para Xylene (mg/L)	< 4	< 4	< 4	< 4	< 4	---
Ortho Xylene (mg/L)	< 2	< 2	< 2	< 2	< 2	---

Note [1]: Bolded letters indicate exceedance in discharge limits at flow band of 400 –600m³ /day.

[2]: KSD100/DHEPZ052: Fire Station in Canton Road;

KSD100/DHE053: West Kowloon Reclamation (replaced adjacent drillhole KSD100/DHE056);

KSD100/DHEPZ113: Petrol station in Skyway House;

KSD100/DHE120: Former shipyard site in West Kowloon Reclamation Area;

KSD100/DHE063: industrial activities west Canton Road

[3]: There will be no groundwater discharge from DHE120 as there will only be at-grade rail works

[4]: ProPECC Note 3/94: Contaminated Land Assessment and Remediation

[5]: According to TM-Water, the chemicals concentration for TPH, dioxin, BTEX and PAH should be below the Reporting limit. Discharges of PCB, PAHs, petroleum oil, pesticide and toxicant into foul sewers, inland waters and coastal waters are prohibited. As the presence of these chemicals is not known at this stage, the groundwater cannot be discharged to the stormwater or foul sewer directly.

It can be seen from the above table that the maximum temperature of the samples are less than 40°C and the pH of the samples are in the range of 6-9, which comply with the standards stipulated in TM-Water. In addition, the concentration of Cr, Ni, As, Cu, Pb, Zn, and Ba are well below the TM-Water limits. However, exceedances in heavy metals (Cd and Hg) contents are observed at locations KSD100 / DHEPZ052 (Fire Station in Canton Road), KSD100 / DHE053 (West Kowloon Reclamation), and KSD100/DHEPZ113 (Petrol station in Skyhouse).

(b) Impact on health of construction workers

The Dutch ABC Values for groundwater are based on the use of groundwater for potable supply. As this is rarely the case in Hong Kong, the Dutch B Values are not necessarily appropriate for assessing the requirement of groundwater remediation, particularly within urban areas where there may be numerous diffuse sources of historical contamination within the vicinity. Hence, the Dutch C values are used for assessment.

When comparing the groundwater with the Dutch levels, 4 groundwater samples exceed the Dutch C Levels. The analytical results exceeding the Dutch C Levels are given in Table 8-4.

Table 8-4 : Summary of groundwater samples exceeding Dutch C Level

Drillhole reference	Depth (mbgl)	Contaminant	Concentration (mg/L)	Dutch C Limit (mg/L)
KSD100/DHEPZ052	8.0m	Copper Lead	230 210	200 200
KSD100/DHE053^[1]	6.5m	Copper Mercury	340 2.5	200 2
KSD100/DHE063	3.0m	Copper	400	200
KSD100/DHEPZ113	6.5m	Copper Lead Mercury	330 210 2.9	200 200 2

Notes:

[1] According to the record for Drillhole KSD100/DHE056 (see Figure 2 of Appendix 10-2), there is distributed marine deposit starting from approximately 5.8m deep. The on-site Contamination Specialist decided to take soil samples at 0.5, 1 and 3m deep. This drillhole was backfilled after sampling. However, the amount of groundwater collected before backfilling of the borehole was found to be insufficient for the required analytical testing. As such, groundwater was collected at an adjacent Drillhole KSD100/DHE053 (835327m easting and 818111m northing) as determined by the on-site Contamination Specialist.

The groundwater analytical results indicate occasionally elevated concentrations over the Dutch C level of metals including copper, lead and mercury. Such results are not considered unusual for groundwater in urban areas, where there are numerous potential diffuse sources of contamination. Free product was not observed in any of the samples or drillholes.

The impact of groundwater on the health of construction workers is based on the Dutch C Value as a screening tool, followed by a risk assessment approach where elevated concentrations of contaminants are present. The assessment methodology is given in the Contamination Assessment Report in Appendix 10-2. Table 8-5 below summarizes the Risk Based Screening Levels (RBSL) for each contaminant. Specific values for the sources of reference for individual factors are given in Appendix 10-2.

Table 8-5 : Risk Based Screening Levels for selected contaminants in groundwater

Contaminants	THQ	Risk	RfDo	SFo		BW	ATn	ATc	IR	ED	EF	RBSL (mg/L)
Copper	1	--	0.005		--	60	5	--	0.02	5	312	17500
Lead	--	0.0004	--		0.28	60	--	70	0.02	5	312	70200
Mercury	1	--	0.0001		--	60	5	--	0.02	5	312	351

Note [1]: THQ-Taget Hazard Quotient for chemical

Risk- Taget excess individual lifetime cancer risk

RfD_o-Chronic Oral Reference dose

SF_o- Carcinogenic slope factor

BW-Body Weight

AT_n-Averaging time for non-carcinogens

AT_c-Averaging time for carcinogens

IR-Water Ingestion Rate

ED-Exposure Duration

EF-Exposure Frequency

RBSL-Risk-Based Screening Level for Groundwater

Although the contamination of groundwater exceeds Dutch C level, none of the samples exceed the calculated RBSL for construction workers. Hence, remedial action of groundwater is not considered necessary.

8.4.2 Recommended Mitigation Measures

In accordance with the Practice Note for Professional Persons on Construction Site Drainage, Environmental Protection Department, 1994 (ProPECC PN 1/94), construction phase mitigation measures shall include the following:

8.4.2.1 Construction Runoff and Site Drainage

· At the start of site establishment (including the barging facilities), perimeter cut-off drains to direct off-site water around the site should be constructed with internal drainage works and erosion and sedimentation control facilities implemented. Channels (both temporary and permanent drainage pipes and culverts), earth bunds or sand bag barriers should be provided on site to direct stormwater to silt removal facilities. The design of the temporary on-site drainage system will be undertaken by the contractor prior to the commencement of construction.

· The dikes or embankments for flood protection should be implemented around the boundaries of earthwork areas. Temporary ditches should be provided to facilitate the runoff discharge into an appropriate watercourse, through a site/sediment trap. The sediment/silt traps should be incorporated in the permanent drainage channels to enhance deposition rates.

· The design of efficient silt removal facilities should be based on the guidelines in Appendix A1 of ProPECC PN 1/94, which states that the retention time for silt/sand traps should be 5 minutes under maximum flow conditions. Sizes may vary depending upon the flow rate, but for a flow rate of 0.1 m³/s a sedimentation basin of 30m³ would be required and for a flow rate of 0.5 m³/s the basin would be 150 m³. The detailed design of the sand/silt traps shall be undertaken by the contractor prior to the commencement of construction.

· Construction works should be programmed to minimize surface excavation works during the rainy seasons (April to September). All exposed earth areas should be completed and vegetated as soon as possible after earthworks have been completed, or alternatively, within 14 days of the cessation of earthworks where practicable. If excavation of soil cannot be avoided during the rainy season, or at any time of year when rainstorms are likely, exposed slope surfaces should be covered by tarpaulin or other means.

· The overall slope of the site should be kept to a minimum to reduce the erosive potential of surface water flows, and all trafficked areas and access roads protected by coarse stone ballast. An additional advantage accruing from the use of crushed stone is the positive traction gained during prolonged periods of inclement weather and the reduction of surface sheet flows.

· All drainage facilities and erosion and sediment control structures should be regularly inspected and maintained to ensure proper and efficient operation at all times and particularly following rainstorms. Deposited silt and grit should be removed regularly and disposed of by spreading evenly over stable, vegetated areas.

· Measures should be taken to minimise the ingress of site drainage into excavations. If the excavation of trenches in wet periods is necessary, they should be dug and backfilled in short sections wherever practicable. Water pumped out from trenches or foundation excavations should be discharged into storm drains via silt removal facilities.

· Open stockpiles of construction materials (for example, aggregates, sand and fill material) of more than 50m³ should be covered with tarpaulin or similar fabric during rainstorms. Measures should be taken to prevent the washing away of construction materials, soil, silt or debris into any drainage system.

· Manholes (including newly constructed ones) should always be adequately covered and temporarily sealed so as to prevent silt, construction materials or debris being washed into the drainage system and storm runoff being directed into foul sewers.

· Precautions be taken at any time of year when rainstorms are likely, actions to be taken when a rainstorm is imminent or forecasted, and actions to be taken during or after rainstorms are summarised in Appendix A2 of ProPECC PN 1/94. Particular attention should be paid to the control of silty surface runoff during storm events, especially for areas located near steep slopes.

· All vehicles and plant should be cleaned before leaving a construction site to ensure no earth, mud, debris and the like is deposited by them on roads. An adequately designed and sited wheel washing facilities should be provided at every construction site exit where practicable. Wash-water should have sand and silt settled out and removed at least on a weekly basis to ensure the continued efficiency of the process. The section of access road leading to, and exiting from, the wheel-wash bay to the public road should be paved with sufficient backfall toward the wheel-wash bay to prevent vehicle tracking of soil and silty water to public roads and drains.

· Oil interceptors should be provided in the drainage system downstream of any oil/fuel pollution sources. The oil interceptors should be emptied and cleaned regularly to prevent the release of oil and grease into the storm water drainage system after accidental spillage. A bypass should be provided for the oil interceptors to prevent flushing during heavy rain.

· Construction solid waste, debris and rubbish on site should be collected, handled and disposed of properly to avoid water quality impacts. Requirements for solid waste management are detailed in Section 9 of this Report.

· All fuel tanks and storage areas should be provided with locks and sited on sealed areas, within bunds of a capacity equal to 110% of the storage capacity of the largest tank to prevent spilled fuel oils from reaching water sensitive receivers nearby.

· By adopting the above mitigation measures with Best Management Practices (BMPs) it is anticipated that the impacts of construction site runoff from the construction site will be reduced to an acceptable levels before discharges.

8.4.2.2 Tunnelling Works

· Cut-&-cover tunnelling work should be conducted sequentially to limit the amount of construction runoff generated from exposed areas during the wet season (April to September).

· Uncontaminated discharge should pass through settlement tanks prior to off-site discharge

· The wastewater with a high concentration of SS should be treated (e.g. by settlement in tanks with sufficient retention time) before discharge. Oil interceptors would also be required to remove the oil, lubricants and grease from the wastewater.

· Direct discharge of the bentonite slurry (as a result of D-wall and bored tunnelling construction) is not allowed. It should be reconditioned and reused wherever practicable. Temporary storage locations (typically a properly closed warehouse) should be provided on site for any unused bentonite that needs to be transported away after all the related construction activities are completed. The requirements in ProPECC PN 1/94 should be adhered to in the handling and disposal of bentonite slurries.

8.4.2.3 Sewage Effluent

· Portable chemical toilets and sewage holding tanks are recommended for handling the construction sewage generated by the workforce. A licensed contractor should be employed to provide appropriate and adequate portable toilets and be responsible for appropriate disposal and maintenance.

8.4.2.4 Groundwater from Contaminated Areas

Direct discharge of groundwater is not adopted. Contaminated groundwater from dewatering process should be recharged back into the ground at the discharged wells in the stockpile areas or temporary work areas as shown in Figure 8-3. The groundwater recharging wells will be selected at places where the groundwater quality will not be affected by the recharge operation as indicated in Section 2.3 of the TM-Water.

The Contractor shall perform ambient measurements on the groundwater quality at the WKN and the cut-&-cover tunnel to the north of WKN with reference to ProPECC PN3/94 “Contaminated Land Assessment and Remediation”, prior to the selection of the recharge wells; and submit a working plan to EPD for agreement. The measurement data of the groundwater will serve as the baseline and the pollutant levels of the groundwater to be recharged shall be measured and not be higher than the baseline measurement at the recharge well.

Apart from the mitigation measures mentioned in S8.4.2.1 and S8.4.2.2, the following additional mitigation measures are proposed to minimize the release of contaminants:

· Free products shall be removed by installing the petrol interceptor prior to recharge;

· Groundwater monitoring wells will be installed to monitor the effectiveness of the recharge wells. The locations of the monitoring wells will be near to the recharge points. During the recharge period, the groundwater level at the monitoring well shall be monitored to ensure that there is no likelihood of locally risen groundwater level and transfer of pollutants beyond the site boundary. Details of groundwater monitoring are given in the EM&A Maunal.

In addition, before excavation, the Contractor shall update the extent of potential groundwater contamination by collecting more groundwater samples along the alignment. The effluent limits and reporting limits are shown in Table 8-3. The Contractor should apply for a discharge licence under the WPCO through the Local Control Office of EPD for groundwater recharge operation.

8.4.3 Residual Impacts

Residual impacts during the construction phase are not anticipated provided that the above mitigation measures are implemented.

8.5 Operational Water Quality Impact

There will be no direct discharge of wastewater into the Victoria Harbour during the operational stage. Hence, quantitative water quality dispersion modelling is considered not necessary. Other water quality issues relevant to the operational phase are described in the following sections.

8.5.1 Pollution Sources & Prediction of Impacts

Potential water pollution sources during the operational phase are summarised below:

· Runoff from rail track and operational tunnel drainage;

· Station runoff;

· Discharge from fresh water cooled facilities; and

· Sewage from station operation.

8.5.1.1 Run off from Rail Track

Since all tracks are contained in concrete tunnel box, there will be no rainwater runoff. The tunnel wall will be equipped with water-tight liner and design for no seepage. The amount of groundwater seepage into the tunnel will be insignificant. Any tunnel run-off could be contaminated with limited amount of grease from passing trains or from maintenance activities. Standard designed silt trap and oil interceptor will be provided to remove the oil, lubricants, grease, silt, grit and debris from the wastewater before discharging into stormwater drainage. The waste will then be disposed of as general refuse and industrial wastes as described in S9.3. No adverse impact on marine environment is anticipated.

8.5.1.2 Station Runoff

Rainwater runoff from station structure (e.g. ventilation building, entrance etc) is not contaminated and hence has no adverse water quality impact.

8.5.1.3 Discharge from Fresh Water Cooling Facility

The discharge water from the fresh water-cooling facility (located in WKN) will contain small amount of dust/chemical. The discharge will be small in quantity and will be connected to main sewer system of the station.

According to the information from Design Team, three types of chemicals including, Drew 2215, Biosperse 280 and Hanmol P-50, will be added into the condenser water to control corrosion and micro-organism growth. These chemicals have been widely adopted in Hong Kong. They are described below:

Drew 2215	An ortho-phosphate based liquid cooling water treatment chemical which is an inherently biodegradable compound. It is dosed occasionally to compensate the chemical loss due to regular water loss in the condenser water system during blowdown or winddrift. The dosage volume is about 32L each time, resulting in the final concentration of around 100ppm.
Hanmol P-50	An oxidizing biocide and is used as a disinfectant to the cooling water. It is dosed twice per week with dosage volume of around 75L. The chemical content of Hanmol P-50 is sodium hypochlorite, which containing 12% w/w available chlorine. 1 ppm of the Hanmol P-50 will be used in the proposed condenser water system.
BIOSPERSE 280	A broad-spectrum biocide and will be shot dosed twice per week into the condenser water system to control the growth of microorganism. The dosage volume is about 5L each time, resulting in concentration of 200ppm inside the condenser water system. In a typical cooling system, 35% of the BIOSPERSE 280 will decompose in 1 hr, 75% is lost in 24 hours and 92% is lost in 48 hrs.

(a) Impact on Sewerage System

Potential water quality impact of the proposed fresh water cooling facility will be the daily bleed-off (~ 5m³ per day) from the condenser water. The bleed off will be used as flushing water and stored in flushing tanks. After flushing, the bleed-off, together with the raw sewage will be pumped to the Stonecutters Island Sewage Treatment Works (SCSTW) for chemical enhanced primary treatment before discharging into the harbour. As there is no biological treatment involved inside the sewage treatment plant, it is considered that there is no significant impact on the sewage treatment works from ecotoxicology perspective.

(b) Impact on Environment

The amount of DREW 2215 in the breed-off (~5m³ per day) from the condenser water system is 100 ppm. The concentration of the DREW 2215 will be further reduced after mixed with other wastewater generated inside the station. In addition, due to the high dilution capacity of the SCSTW and the inherently biodegradable property of DREW 2215, it is considered that there is no significant impact of Drew 2215 on the marine water quality after discharging from the SCSTW in the ecotoxicology standpoint.

Based on the dosage rate of Hanmol mentioned earlier, the maximum residual chlorine amount will be 0.12 ppm, which is lower than the residual chlorine content in drinking water (~1ppm). Hence, it is considered that Hanmol P-50 in the condenser water will have no impact on the environment.

For BIOSPERSE 280, due to the intermittent nature of the biocide dosing and bleeding off, the fast degradation rate of Biosperse 280 and the high dilution effect from the SCSTW, it is considered that the impact on marine environment is insignificant.

Although the chemicals used in fresh water cooling facilities have no adverse impact on the sewerage system and the environment, the Project Proponent is required to apply for the discharge licence under WPCO before the operation of the station.

8.5.1.4 Sewage from Station

A Design & Build Contractor will be appointed by the Project Proponent to conduct the detailed design and the construction and he will be responsible for carrying out the Sewerage Impact Assessment and submit to the relevant government departments for approval. Review of information from MOS Railway suggests that the typical Average Dry Weather Flow (ADWF) for a train station (without top-side properties) would be about 0.8l/s, which would be equivalent to about 55m³/day, assuming 19 hours of operation. It is therefore anticipated that the ADWF for the WKN would be of similar order and probably in the order of 50-100m³ /day. Given the small quantity of the ADWF for WKN, the capacity of the foul sewer is adequate for the proposed sewage discharge. Hence, no water quality impact is anticipated. The sewage discharge location is shown in Appendix 8-1.

8.5.2 Recommended Mitigation Measures

Mitigation measures are only required to mitigate runoff from track during the operational phase. With the implementation of the following mitigation measures, no residual impact during operational phase is anticipated.

· Track drainage channels discharge should pass through oil/grit interceptors/chambers to remove oil, grease and sediment before being pumped to the public stormwater drainage system;

· The silt traps and oil interceptors should be cleaned and maintained regularly; and

· Oily contents of the oil interceptors should be transferred to an appropriate disposal facility, or to be collected for reuse, if possible.

8.6 Conclusion

8.6.1 Construction Phase

Potential water pollution sources have been identified as construction runoff, sewage from site workforce, drainage diversion and groundwater contamination. Mitigation measures including covering excavated materials, carrying out excavation during dry seasons as far as possible and providing sedimentation tanks etc are recommended to mitigate any adverse water quality impacts.

Chemical tests have been conducted for ground water samples collected during the site investigation. Results indicate that some of the samples near the WKN and along the northern tunnels would be contaminated and exceed the discharge limit stipulated in TM-Water. Direct discharge of groundwater is thus not recommended. However, none of the samples exceed the calculated RBSL and therefore remedial action is not considered necessary for groundwater. To proper handle the groundwater, the groundwater during dewatering process should be re-charged on-site with careful monitoring to minimize environmental impact.

8.6.2 Operational Phase

The operational water quality impact for track run-off and tunnel seepage will have no adverse water quality impact provided that mitigation measures are incorporated in the design. The fresh water cooling system for station and tunnels will not cause adverse water quality impacts.

All proposed mitigation measures are clearly defined in the Environmental Mitigation Implementation Schedule.

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