5. NOISE

5.1 Introduction

5.1.1 Westwood Hong & Associates Ltd (WHA) was commissioned to conduct an environmental noise impact assessment on the proposed comprehensive development on Yau Tong Bay (Figure 5.1). The guidance for environmental considerations is provided in the Technical Memorandum on Environmental Impact Assessment Process (EIAO-TM)^[1].

5.1.2 This report presents a noise assessment with considerations given to:

· the existing noise environment in the vicinity of the proposed Development;

· the construction noise impacts on the planned and existing noise sensitive receivers (NSRs) during the construction phase of the proposed Development;

· the cumulative construction noise impacts due to other concurrent major construction activities in the vicinity on the planned and existing noise sensitive receivers (NSRs);

· the road traffic noise impact on the Development;

· the aircraft noise impact on the Development;

· the industrial noise impacts on the planned and existing noise sensitive receivers (NSRs) during the operational phase of the Development;

· the industrial noise impacts due to the operations of the remaining lots on the Development; and

· recommend mitigation measures where necessary to achieve acceptable noise levels of the affected NSRs.

Development Options due to Different Alignment Options of WCR

5.1.3 As advised by the Traffic Consultant (MVA HK Ltd) and TD, the Territory Development Department (TDD) is actively investigating the feasibility of alternative tunnel route alignment for the Western Coast Road (WCR) while there is still opportunity for adopting the WCR coastal alignment option. There is still no final decision on which alignment to be adopted for WCR.

5.1.4 In this noise assessment report, the scenarios of the WCR tunnel alignment (i.e. Development Option 1 - Minimised Reclamation) together with the WCR coastal alignment (i.e. Development Option 2 - Full Reclamation) are assessed.

Development Options due to I/R Interface Problem

5.1.5 Within the Yau Tong Bay, some existing industrial establishments owned by non-consenting owners may cause an I/R interface noise concern to the proposed residential development (Figure 5.2) :-

(a) Wing Shan Industrial Building (formerly known as Agincourt Industrial Building) at Marine lot YTML 73 and 74;

(b) Sawmill at Marine lot YTML 1, Shipyard at Marine lot YTML 2-4; and

5.1.6 To alleviate the potential noise problems generated from the remaining industrial lots to the nearby residents, special arrangement of building layouts for the Development is proposed. The scenario of without I/R interface problem (i.e. Development Option A - Without I/R Interface) together with the scenario of with I/R interface problem (i.e. Development Option B - With I/R Interface) are assessed in this report.

5.2 Site Location and Building Layout

Site Location

5.2.1 The site adjoins Cha Kwo Ling Road to the north and east and, Ko Fai Road to the south. Future Western Coast Road (WCR) – Coastal Option will be located to the west of the site (Figure 5.1).

Building Layouts

5.2.2 With the consideration of different options for WCR alignment, I/R interface and different stages, six different development scenarios are proposed and assessed in this report (Figures 5.3a - 5.3f). The six development options are:-

· WCR Tunnel Options:

Development Option 1A - Minimised Reclamation without I/R Interface

Development Option 1B (Stage A) - Minimised Reclamation with I/R Interface

Development Option 1B (Stage B) - Minimised Reclamation with all industrial premises removed

· WCR Coastal Options:

Development Option 2A - Full Reclamation without I/R Interface

Development Option 2B (Stage A) - Full Reclamation with I/R Interface

Development Option 2B (Stage B) - Full Reclamation with all industrial premises removed

5.2.3 Both development options have similar development parameters. Each option comprises five primary and three secondary schools, two office towers atop a shopping arcade and residential towers of 49-storey high atop a podium (Figures 5.3a - 5.3f, 5.4 and 5.5).

5.2.4 The residential towers have incorporated setback distances of about 30m from the southern site boundary adjoining Ko Fai Road and more than 40m from Western Coast Road for the WCR Coastal Options.

5.2.5 With the proposed schools and the office towers atop the shopping arcade located along Cha Kwo Ling Road, the separation between the Noise Sensitive Receivers (NSRs) and Cha Kwo Ling Road is significant and the traffic noise impact caused by Cha Kwo Ling Road is substantially reduced for the residential towers.

5.2.6 Some residential towers are assumed to have facades without openable windows (Figures 5.6a to 5.6f). Single aspect building design has been incorporated for the scenarios with I/R interface problems (Figures 5.6b and 5.6e).

5.3 Noise Criteria

5.3.1 The principal legislation for the control of construction and operation noise is given in the Noise Control Ordinance (NCO). The guidelines for the assessment of construction and operational noise are given in the Environmental Impact Assessment Ordinance (EIAO). Various Technical Memoranda (TMs), which stipulate the control approaches and criteria have been issued under the NCO and EIAO. The following TMs are applicable to the control of noise from construction activities and plant operation:-

· Technical Memorandum on Environmental Impact Assessment Process (EIAO-TM)^[1];

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

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

· Technical Memorandum on Noise From Percussive Piling (PP-TM)^[4]; and

· Technical Memorandum for the Assessment of Noise from Places other than Domestic Premises, Public Places or Construction Sites (IND-TM)^[5].

Construction Noise Criterion

5.3.2 Construction work should comply with the requirements of the “Noise Control Ordinance” (NCO), the “Technical Memorandum on Environmental Impact Assessment Process” (EIAO-TM), “Technical Memorandum on Noise from Construction Work other than Percussive Piling” (GW-TM) and the “Technical Memorandum on Noise from Construction Work in Designated Areas” (DA-TM).

5.3.3 Noise standards for daytime construction activities are given in Table 1B of the “Technical Memorandum on Environmental Impact Assessment Process” (EIAO-TM). The noise standards are dependent on the uses of the NSRs. The day-time construction noise (on any day not being a Sunday or general holiday) should be limited to 75dB(A) (L_eq, 30-mins) at the sensitive residential buildings with opened windows and, 70dB(A) and 65dB(A) (during examinations) at the school and educational buildings in the neighbourhood. EIAO-TM states that the noise criteria for construction or decommissioning of designated projects, shall be met as far as practicable. All practicable mitigation measures shall be exhausted and the residual impacts are minimized.

5.3.4 A Construction Noise Permit (CNP) is required for any construction work carried out during the night-time (2300 to 0700 hours), evening (1900 to 2300 hours) and any time on general holidays, including Sunday.

5.3.5 The control of percussive piling is governed at all times by “Technical Memorandum on Noise From Percussive Piling” (PP-TM).

Traffic Noise Criterion

5.3.6 In the EIAO-TM, a peak hour maximum noise levels of 70dB(A) L₁₀ and 65dB(A) L₁₀ at the facades of residential buildings and educational institutions are recommended. These noise limits apply to premises relying on open windows as the primary means of ventilation. A brief description of relevant noise terminology is given in Appendix 5A.

Aircraft Noise Criteria

5.3.7 It is recommended in the EIAO-TM that the NEF25 contour of the Chek Lap Kok Airport should not be exceeded for residential development.

Industrial Noise Criteria

5.3.8 In accordance with the IND-TM, an Area Sensitivity Rating (ASR) of "B" should be used. The Acceptable Noise Levels are shown in Table 5.1.

Table 5.1 Acceptable Noise Levels for daytime, evening and night-time periods

Time Period	Acceptable Noise Levels (ANL)
Day (0700 to 1900 hours) and evening (1900 to 2300 hours)	65dB(A)
Night (2300 to 0700 hours)	55dB(A)

5.3.9 The EIAO-TM specifies that the noise from the fixed sources under planning should be 5dB(A) below the ANL or the prevailing background noise levels.

5.4 Site Survey

Dates of Site Inspections

5.4.1 Site inspections were conducted at the site on 5 Aug 1997, 23 November 1998 and 18 October 2000. The main objective of the surveys was to establish whether the Development would be significantly affected by the road traffic or other industrial sources in the neighbourhood. Additional site visits to Tsing Yi Shipyards were made to further familiarise with the operation of shipyards on 30 January 2001, 17 and 22 February 2001.

Survey Personnel

5.4.2 The surveys were conducted by Dr Westwood Hong, Ms Mandy To, Mr Lincoln Fung and Ms Florence Cheng of WHA.

Observations on site

5.4.3 The road traffic was quite heavy on Cha Kwo Ling Road and relatively not heavy on Ko Fai Road during the site surveys. Industrial noise impact was mainly from the industrial buildings located to the south of Ko Fai Road. Inspection on site revealed that the noise sources were mainly rooftop air-cooled condensers and ventilation intakes and discharges located at the facades of the industrial buildings. Photographs taken on site are given in Appendix 5B.

Noise Sensitive Receivers in the Vicinity

5.4.4 The nearest existing Noise Sensitive Receivers (NSRs) in the vicinity were identified as the two new schools (in operation since 09/1999) located at Yau Tong Estate redevelopment, the residents of Yau Tong Centre located at approximately 200m to the south-east, Cha Kwo Ling at approximately 200m to the north-west and Yau Tong Estate redevelopment Phase I (with construction completed in August 2000) at approximately 50m to the east of the site (Figure 5.1).

5.4.5 Future NSRs include planned housing and schools developments at Eastern Harbour Crossing Sites to the north and Yau Tong Estate Redevelopment to the east (Figure 5.7).

Industrial Noise Sources in the Vicinity

5.4.6 The industrial premises in the vicinity were identified as the industrial buildings located at approximately 20m from the southern site boundary. Other industrial installations are the Salt Water Pumping Station and the Gas Pigging Station located to the west of Wing Shan Industrial Building.

Potential Industrial Noise Sources in the Remaining Lots

5.4.7 Inspection of the Wing Shan Industrial Building (Figure 5.2) has revealed that the building has some air-conditioners and exhaust hoods fitted on the northern and southern facades. The eastern and western sides of the building are blank facades. The uses of the building were mainly for godowns and offices.

5.4.8 The Premises for sawmill and storages at Marine lot YTML 1, 25, 26 and 27 were used mainly for storage and did not produce any significant noise levels at the time of the visit.

5.4.9 Inspection of the UDL shipyard at YTML 2-4 has revealed that only maintenance works and without heavy ship manufacturing activities were being carried out.

Instrumentation

5.4.10 The instrumentation used by Westwood Hong & Associates Ltd for the surveys is listed below.

Table 5.2 Instruments used for Noise Surveys

MANUFACTURER	TYPE
Ono Sokki & Bruel and Kjaer	Precision Integrating Sound Level Meters
Ono Sokki & Bruel and Kjaer	Foam Windshields
Bruel and Kjaer	Noise Calibrator Type 4231

5.4.11 The sound level meter was calibrated before use and further checks on completion of the survey confirmed that there had been no significant drift of calibration.

Survey Method

5.4.12 The site was inspected before commencing the noise measurements to ascertain that there was minimal noise from construction and occupational activities being carried out in the vicinity. The occupational activity in the neighbourhood was not considered to have any significant increase on the measured road traffic noise levels.

5.4.13 The sound level meter was adjusted to determine the A-weighted statistical sound pressure levels such as L₁₀, L_max, L₉₀ and L_eq. A simple description of the statistical acoustical terms is given in Appendix 5A.

Microphone Locations

5.4.14 The microphone was positioned at approximately 1.2m above local ground level. A measurement period of 5 minutes was employed for the road traffic noise measurements to minimize any likely adverse effect from construction and occupational activities in the neighbourhood.

Measured Road Traffic Noise Levels

5.4.15 The measured road traffic noise levels were in the range of 80 - 82dB(A)L₁₀ at the eastern site boundary facing the junction of Cha Kwo Ling Road and Yau Tong Road.

Measured Industrial Noise Levels

5.4.16 The measured industrial noise levels at the southern site boundary were in the range of 78 - 79dB(A) L_eq at a distance of 20m away from the Yau Tong industrial City. These measured noise levels included the general background noise caused by the road traffic in the neighbourhood.

Site Survey conducted in the late evening has revealed that the Salt Water Pumping Station was relatively quiet with measured noise levels in the range of 47 – 49 dB(A) L_eq at approximately 10m from the pumping station. Inspection of the Gas Pigging Station has indicated that there were only pipes within the station compound with insignificant noise emission.

Measured Industrial Noise Levels at the Remaining Lots

5.4.17 Noise measurements made at the 3/F podium at the rear of the Wing Shan Industrial Building show that the noise levels were in the range of 63-65 dB(A) L_eq, measured at 3m from the facade, indicating that the noise emanating from the building was not significant.

5.4.18 The measured noise levels were in the range of 71-72 dB(A) at 3m from the front façade of the sawmill and storages at Marine lot YTML 25, 26 and 27 facing Cha Kwo Ling Road and in the range of 61-65dB(A) at 3m from the front façade of the sawmill at Marine lot YTML 1. These measured noise levels were dominated by the nearby construction works and traffic.

5.5 Construction Noise Assessment

Assessment Methodology

5.5.1 The methodology for assessing the construction noise other than percussive piling is based on GW-TM, as summarised in the following:-

i) To identify the affected NSRs within the Study Area;

ii) To identify the phasing of construction work and, locations and required number of the construction plant items;

iii) To obtain the sound power levels in dB(A) of the construction equipment from the GW-TM;

iv) To determine the distance from the effective noise source location (or “notional source position”) to the NSRs and distance attenuation (from geometric spreading and other absorption effects where appropriate), barrier corrections and reflection corrections at the NSR as prescribed in the GW-TM;

v) To calculate the Corrected Noise Level (CNL) which will be generated by the construction works at the NSRs;

vi) To propose direct mitigation measures, if necessary, to minimise the impact by the construction work in order to comply with the stipulated noise limits.

Project Programme

5.5.2 The anticipated commencement date of the construction works for Yau Tong Bay Development is October 2005. The overall construction period of the whole development will be approximately 10 years and the anticipated completion date would be in early 2016.

Identified Planned and Existing Noise Sensitive Receivers (NSRs) in the Vicinity

5.5.3 The Noise Sensitive Receivers (NSRs) closest to the proposed project site have been selected as representative NSRs. The information on the completion year of the nearby development projects is extracted from the letter prepared by Hong Kong Housing Authority (Appendix 5C). They are shown in the following Table 5.3 and Figure 5.7.

Table 5.3 Representative NSRs closest to the Development

Representative NSRs
RYTE1	Yau Tong Estate (Phase 1)
RYTE2	Yau Tong Estate (Phase 2)
RYTE3	Yau Tong Estate (Phase 3)
RYTE5	Yau Tong Estate (Phase 5)
RYCT	Yau Tong Centre
RCKL	Cha Kwo Ling
REHC1	Eastern Harbour Crossing Site (Phase 1)
REHC2	Eastern Harbour Crossing Site (Phase 2)
REHC3	Eastern Harbour Crossing Site (Phase 3)
RSCH1	New School at Yau Tong Estate (North)
RSCH2	New School at Yau Tong Estate (South)
RSCH3	New Schools at EHC site

5.5.4 Two new schools (RSCH1 and RSCH2) at the Yau Tong Redevelopment site have started operation since September 1999 and they are located close to the Yau Tong MTR Station. Noise mitigation measures with upgraded glazing and air-conditioners have been provided to these schools for reducing noise impacts from the Station Construction.

5.5.5 In addition, three new schools (RSCH3) at EHC Site located to the north of the site are scheduled to complete construction in September 2004. Noise mitigation measures are expected to be provided by the Government to protect the schools from the significant traffic noise impact from heavily trafficked Cha Kwo Ling Road and that the proposed Development will make provision to provide the required noise mitigation measures if necessary.

Plant Inventory of Construction Equipment (PMEs)

5.5.6 The inventories of the construction equipment (Powered Mechanical Equipment, or PMEs) expected to be used during foundation & sub-structure and building construction stages of the construction phase is summarised in Tables 5.4 and 5.5. The plant inventories listed in these tables have been confirmed to be practical and practicable for completing the works within the construction programme. Different stages of the construction works will be carried out in separate period of time.

Table 5.4 Inventory of PMEs during Foundation Construction

Activity	Equipment	Reference	SWL (dB(A))	No. of units
Foundation	Dumper	066	106	2
	Concrete Pump	047	109	2
	Compressor	002	102	2
	Vibratory Poker	170	113	4
	Crane (mobile)	048	112	2
	Backhoe	081	112	3
	Drilling/ Piling Rig	165	115	6
	Truck	141	112	2
			Sub-SWL = 126 dB(A)

Table 5.5 Inventory of PMEs during Superstructure Construction

Activity	Equipment	Reference	SWL (dB(A))	No. of units
Superstructure	Compressor	002	100	6
	Concrete pump	047	109	4
	Crane (tower)	049	95	6
	Truck	141	112	2
	Vibratory Poker	170	113	4
	Hoist	122	95	4
	Generator, silenced	102	100	4
	Compactor	050	105	4
	Backhoe	081	112	4
	Bar Bender	021	90	6
	Bulldozer	030	115	2
	Saw	201	108	2
	Concrete Lorry Mixer	044	109	2
			Sub-SWL = 125 dB(A)

Predicted Construction Noise Impacts

5.5.7 The noise impacts due to the construction of the proposed Development using the plant inventory as shown in Tables 5.4 and 5.5 are predicted in this section. The objective is to assess the project feasibility during this planning stage and to identify if there is any potential constraint on the works programme or the use of the construction equipment.

5.5.8 The following Table 5.6 lists the NSRs, their setback distances and the predicted CNLs due to the construction works.

Table 5.6 Predicted Corrected Noise Levels at NSRs due to foundation and superstructure works (Unmitigated)

		Distance to Notional Source	Predicted CNLs (dB(A))		Criteria
Representative NSRs		Position (m)	Foundation	Superstructure	(dB(A))
RYTE1	Yau Tong Estate (Phase 1)	180	74	74	75
RYTE2	Yau Tong Estate (Phase 2)	216	73	72	75
RYTE3	Yau Tong Estate (Phase 3)	180	69	69	75
RYTE5	Yau Tong Estate (Phase 5)	160	75	75	75
RYCT	Yau Tong Centre	300	60	59	75
RCKL	Cha Kwo Ling	236	67	66	75
REHC1	Eastern Harbour Crossing Site (Phase 1)	228	72	71	75
REHC2	Eastern Harbour Crossing Site (Phase 2)	156	76	75	75
REHC3	Eastern Harbour Crossing Site (Phase 3)	115	78	77	75
RSCH1	New School at Yau Tong Estate (North)	276	66	65	70
RSCH2	New School at Yau Tong Estate (South)	190	69	68	70
RSCH3	New Schools at EHC site	76	77	76	70

5.5.9 The assessment results show that the predicted construction noise levels due to foundation and superstructure works at NSRs REHC2 and RSCH3 (with predicted CNL bolded in Table 5.6) do not comply with the noise criteria. Sample calculations at the worst affected NSRs are given in Appendix 5D.

Mitigation Measures for Construction Noise

5.5.10 The predicted day-time construction noise levels at some of the NSRs exceed the criteria stipulated in the EIAO-TM. The following mitigation measures are recommended to mitigate the construction noise impact:-

· Scheduling of work - The Contractor has to make the choice of the number and types of construction equipment taking into account the use of quiet plant while devising a feasible work programme.

· Siting of facilities - This includes minimizing noisy operations during examination periods; avoiding simultaneous operation of noisy equipment; retaining existing features that can act as a noise barrier until the last phase; and erecting, as early as possible, any new structures which will have the effect of screening noise sources. Such screens can reduce noise levels by 5dB(A) or more. Noisy equipment, such as emergency generators and water pumps, should always be sited as far as possible from noise sensitive receivers. Consideration should also be given to the use of structures such as site offices and stores as noise barriers.

· Movable noise barrier - A typical design being adopted extensively for local construction sites is a 3 m high wooden framed barrier with a small cantilevered upper portion infilled with marine ply of density no less than 20 kg/m² on a skid footing. It could provide up to 5 dB(A) attenuation if they are correctly positioned for static plant such as air compressors, drilling rigs, water pumps, generators and concrete pumps.

· Use of Quiet Powered Mechanical Equipment (PME) - The contractor should be requested, as far as possible, to use quiet PME, whose actual SWL is less than the value specified in GW-TM. This is one of the most effective measures and is increasingly practicable because of the availability of quiet equipment. Examples of SWLs for specific silenced PME, which are generally available in Hong Kong, are given in the following Table 5.7.

Table 5.7 Listing of Quiet PME items

Powered Mechanical Equipment (PME)	Maximum SWL, dB(A)	Reference
Concrete Pump	106	BS 5228: Part 1: 1997 Table 6
Compressor	100	GW - TM CNP001
Generator	95	GW - TM CNP103
Vibratory Poker	102	BS 5228: Part 1: 1997 Table C6
Crane (mobile)	109	BS 5228: Part 1: 1997 Table C6
Backhoe	105	BS 5228: Part 1: 1997 Table C3
Drilling/Piling Rig	105	GW - TM CNP162
Truck	102	BS 5228: Part 1: 1997 Table C9
Bulldozer	109	BS 5228: Part 1: 1997 Table C3
Saw	105	BS 5228: Part 1: 1997 Table C7
Concrete Lorry Mixer	100	BS 5228: Part 1: 1997 Table C6

5.5.11 Good site practice and noise management can considerably reduce the impact of the construction sites’ 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) 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, should, where possible, be orientated so that the noise is directed away from nearby NSRs;

· silencers or mufflers on construction equipment should be utilised and should be properly maintained during the construction period;

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

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

Predicted Construction Noise Impacts (Mitigated)

5.5.12 The residual noise impacts due to the construction of the proposed Development incorporating the quiet plants as shown in Table 5.7 and movable noise barriers for concrete pumps are predicted in this section. The following Table 5.8 summarises the predicted mitigated CNLs due to the construction works.

Table 5.8 Predicted Corrected Noise Levels at NSRs due to foundation and superstructure works (Mitigated)

Representative NSRs		Distance to Notional Source Position (m)	Predicted Mitigated CNLs (dB(A))		Criteria (dB(A))
Representative NSRs		Distance to Notional Source Position (m)	Foundation	Superstructure	Criteria (dB(A))
RYTE1	Yau Tong Estate (Phase 1)	180	67	67	75
RYTE2	Yau Tong Estate (Phase 2)	216	65	65	75
RYTE3	Yau Tong Estate (Phase 3)	180	62	62	75
RYTE5	Yau Tong Estate (Phase 5)	160	68	68	75
RYCT	Yau Tong Centre	300	52	52	75
RCKL	Cha Kwo Ling	236	60	60	75
REHC1	Eastern Harbour Crossing Site (Phase 1)	228	65	65	75
REHC2	Eastern Harbour Crossing Site (Phase 2)	156	68	68	75
REHC3	Eastern Harbour Crossing Site (Phase 3)	115	70	71	75
RSCH1	New School at Yau Tong Estate (North)	276	58	58	70
RSCH2	New School at Yau Tong Estate (South)	190	61	61	70
RSCH3	New Schools at EHC site	76	69	69	70

5.5.13 The assessment results show that the predicted mitigated construction noise levels due to foundation and superstructure works at all NSRs comply with the noise criteria. Sample of calculation at the worst affected NSRs is given in Appendix 5E.

Cumulative Impact due to Construction of Other Developments in Yau Tong Area

5.5.14 There are a number of planned and committed housing developments in Yau Tong Area, including Yau Tong Estate Development and East Harbour Crossing Housing Estates. The completion years for the developments are given in Appendix 5C. As the construction of the Development will be commenced in October 2005, there will be a period of overlap of about 2 years with the construction of the Yau Tong Bay Reclamation (Package 1 EIA Study) and EHC3 site.

5.5.15 With reference to the EIA Report titled “Yau Tong Bay Development Environmental Impact Assessment - Reclamation of Yau Tong Bay”, the mitigated construction noise levels at all NSRs due to the construction works are in the range of 36 - 65 dB(A), which comply with the stipulated noise criteria. Noise levels have been predicted at the NSRs based on a sound power level of 121dB(A) for the construction activities at EHC3 site.

5.5.16 The cumulative construction noise impacts caused by the construction of the proposed Development and the construction of nearby developments are summarised in Appendix 5F. Results indicate that the predominant noise impact will be caused by the construction activities at the EHC3 site during the first half year of the construction of the proposed Development with 1 - 5dB(A) exceedance to the NSRs of the housing developments in the vicinity of the EHC3 site. The 1 – 5dB(A) exceedance is attributable to the construction site around EHC site while the proposed Development has a minor contribution to the cumulative noise impact. The cumulative construction noise levels for the remaining period will comply with the stipulated noise criteria.

5.6 Road Traffic Noise Assessment

5.6.1 The noise prediction has been conducted by employing the RoadNoise^[6] computer software licensed to use by WS Atkins.

Traffic Flow Data

5.6.2 Traffic noise calculations have been conducted based on future traffic flow data provided by the Traffic Consultant MVA (HK) Ltd for the local roads for Year 2030. The traffic forecast has been endorsed by the Traffic Engineering (Kln) Division, TD (ref: (27) in EP2/K15/C06 III dated 7 Jan 2002). The Traffic Consultants has advised that, as compared with the traffic forecasts in the previous submission, the updated traffic forecasts have incorporated the latest development and infrastructure assumptions for the South East Kowloon area and the planning assumptions as extracted from “Agreement No. CE81/98 Feasibility Study for Development at Cha Kwo Ling Kaolin Mine Site – Additional Study”. Besides, this set of updated traffic forecasts has been endorsed by Transport Department. The methodology and assumptions adopted to obtain the traffic forecast for Year 2030 are provided by the Traffic Consultant MVA (HK) Ltd. (Appendix 5G). The percentage of heavy vehicles is calculated from the peak figures of light and heavy vehicles. The traffic flow data have been converted to light vehicles and heavy vehicles as defined in "Calculation of Road Traffic Noise (1988)" (CRTN)^[7].

5.6.3 The 2030 traffic flow data for the two WCR Tunnel and Coastal Options prepared by the Traffic Consultant are given in Appendices 5H. Summaries of the traffic flow data for the main roads in the vicinity are given in Tables 5.9 to 5.10. The traffic flow data for the roads included in the noise prediction models are shown in Figures 5.8a to 5.8d.

Table 5.9 Future traffic flow data for year 2030 (WCR Tunnel Option)

	Traffic flow data (Year 2030)
Roads	veh/hr	% of Heavy vehicles
Cha Kwo Ling Road (east section)	1500	24
Cha Kwo Ling Road (west section)	1100	23
Flyover	1900	23
Ko Fai Road	1550	20
Lei Yue Mun Road (to Eastern Harbour Crossing)	7200	14
New Yau Tong Road	2650	18

Table 5.10 Future traffic flow data for year 2030 (WCR Coastal Option)

	Traffic flow data (Year 2030)
Roads	veh/hr	% of Heavy vehicles
Cha Kwo Ling Road (east section)	2700	25
Cha Kwo Ling Road (west section)	4000	25
Ko Fai Road	2200	23
Lei Yue Mun Road (to Eastern Harbour Crossing)	7200	14
Western Coast Road (north bound) (WCR)	1550	34
Cha Kwo Ling Road to WCR	1000	30
WCR to Cha Kwo Ling Road	1050	27
Ko Fai Road to WCR	1050	25
WCR to Ko Fai Road	750	28

Assessment Methodology

5.6.4 The facade noise levels have been predicted based on the traffic flows in Year 2030 for the four development options.

5.6.5 The calculation methods are in accordance with the CRTN and the predicted noise levels at the building facades include a 2.5dB(A) facade reflection and correction factors for effects due to gradient, distance, view angle and barriers.

Noise Mitigation Measures for WCR Coastal Options

5.6.6 For the WCR Coastal Options, it is understood that semi-enclosures and vertical barriers are proposed by PM/NTE’s Consultant to be installed on the future WCR. These mitigation measures will alleviate the noise impact for the towers located at the western portion of the site (Appendix 5I). The calculations have taken into account of the anticipated noise reduction available from the future noise mitigation measures to be implemented to the WCR. The effectiveness of the Development’s proposals and mitigation measures are dependent to a large degree to the Administration’s commitment to mitigation measures on a WCR, if adopted.

5.6.7 For the WCR Coastal Options, noise barriers are proposed to be erected with 5m high roadside and podium edge barriers along Cha Kwo Ling Road and, 5m high podium edge noise barrier facing Ko Fai Road to protect the schools and residential flats of the Development.

Noise Mitigation Measures for WCR Tunnel Options

5.6.8 For the WCR Tunnel options, noise barriers are proposed to be erected with 5m high roadside and podium edge barriers along Cha Kwo Ling Road and, 5m high podium edge noise barrier facing Ko Fai Road to protect the schools and residential flats of the Development.

Predicted Road Traffic Noise Levels at Residential Towers

5.6.9 The predicted road traffic noise levels at the Noise Sensitive Receivers (NSRs) of the residential towers are presented in Figures 5.9a and 5.9b, 5.10a and 5.10b, 5.11a and 5.11b, 5.12a and 5.12b, 5.13a and 5.13b and 5.14a and 5.14b for the 6 options respectively. The results are summarised in Table 5.11.

Table 5.11 Results of Road Traffic Noise Assessments

Road Traffic Noise Assessments	Predicted Maximum Façade Noise Levels, dB(A)	% of Compliance
*WCR Tunnel Options*
Option 1A - Minimised Reclamation without I/R Interface	71dB(A)	99.5%
Option 1B - Minimised Reclamation with I/R Interface (Stage A)	70dB(A)	100%
Option 1B – Minimised Reclamation with I/R Interface (Stage B)	71dB(A)	99.5%
*WCR Coastal Options*
Option 2A - Full Reclamation without I/R Interface	72dB(A)	99.3%
Option 2B - Full Reclamation with I/R Interface (Stage A)	74dB(A)	98.7%
Option 2B – Full Reclamation with I/R Interface (Stage B)	74dB(A)	98.8%

5.6.10 Details of the computer output and input files are shown in Appendices 5Ja & 5Jb, 5Ka & 5Kb, 5La & 5Lb, 5Ma & 5Mb, 5Na & 5Nb and 5Oa & 5Ob for the 6 scenarios respectively. The predicted noise levels for all floors are given in Appendices 5Pa to 5Pf.

Predicted Road Traffic Noise Levels at Schools

5.6.11 Five primary schools and three secondary schools are located along Cha Kwo Ling Road and near the waterfront (Figures 5.3a to 5.3f).

5.6.12 Results indicate that the predicted facade noise levels at the schools will be in the range of 42 - 77dB(A) with some noise-sensitive rooms exceeding the stipulated noise criteria as described Section 5.3 (Figures 5.15a – 5.15f).

Mitigation Measures for Road Traffic Noise

5.6.13 Noise mitigation measures for mitigating traffic noise given in EIAO-TM Annex 13 paragraph 6.1 have been considered and some are incorporated, as mentioned in the following paragraphs.

· Alternative Land Use Arrangement and Siting

For all development options, the non-domestic components have been arranged to the perimeter of the site in order to minimize the impact of traffic noise to the residential units, e.g. office/retail complex and schools were located near Cha Kwo Ling, while residential towers facing Ko Fai Road have been setback 30m from the road. The land use arrangement as shown is considered to be the best option.

· Setback of Residential Towers

The residential towers have incorporated setback distances of minimum 30m from the southern site boundary facing Ko Fai Road and greater than 30m from Western Coast Road for the WCR Coastal Option. For the towers located at the YTML lots 73-74 and 25-27, the design has incorporated maximum setback distances from Cha Kwo Ling Road. It is not possible to incorporate additional setback distances such that the noise impacts will be further reduced significantly.

· Setback and Orientation of Schools

The schools have incorporated maximum setback distances from Cha Kwo Ling Road in order to reduce the traffic noise impact. The windows of the classrooms are mostly perpendicular to the road instead of having a direct facing, thus helping to minimise the traffic noise impact to the schools.

· Building Orientation and Building Design

The present building arrangement proposal is considered as one of the best options from urban design and architectural design point of view. It has minimized the visual impact of the residential towers and overlooking problem of adjacent flats.

The office towers and the shopping arcade, together with the schools, will effectively screen the residential towers from the traffic noise impact from Cha Kwo Ling Road. The majority of the NSRs in the towers will be subject to noise levels within the 70dB(A) criterion.

· Refined Scheme

In order to minimize the traffic noise impact caused by the Western Coast Road (WCR) to the schools of the Development, a Refined Scheme with schools relocated away from the WCR has been developed and assessed with WCR Tunnel Option (Minimised Reclamation) and WCR Coastal Option (Full Reclamation) (Figures 5.16a and 5.16b).

Results of noise assessment indicate that the relocated schools will be subject to insignificant traffic noise levels of not greater than 60dB(A) and that the residential towers will not be adversely affected due to the adequate setback from the WCR. The percentages of exceedence for the WCR Tunnel Option and WCR Coastal Option are 0.5% and 0.2% respectively. Details of traffic noise results are presented in Appendices 5Pg and 5Ph.

· Podium Edge Noise Barriers

The 5m high noise barrier will be required to be erected at the podium edge facing Ko Fai Road and Cha Kwo Ling Road (Figures 5.17a - 5.17h). The 5m high podium edge noise barrier will effectively screen the residential towers from the traffic noise impact due to Ko Fai Road and Cha Kwo Ling Road.

· Purpose-Built Noise Barriers

The effectiveness of erecting noise barriers along Cha Kwo Ling Road has been investigated. Results indicate that 5m high roadside noise barriers will significantly reduce the noise levels at the schools and that at low levels of the residential towers closed to Cha Kwo Ling Road (Figures 5.17a - 5.17h).

· Provision of Upgraded Glazing and Air-conditioners for Residential Towers

As a last resort to reduce the noise impacts on the occupants of the residential Development, window type I (as per EIAO-TM^[3]) with glazing comprising minimum 6mm thick glass pane and well gasketted seal will be installed to the noise sensitive areas including bedrooms, living rooms and dining rooms of the affected residential flats (Figures 5.17a – 5.17h).

It is recommended to provide air-conditioners to all noise sensitive areas of the affected residential flats so that the occupants will not solely rely on open windows for ventilation and that the adverse noise impact caused by the road traffic will be effectively reduced (Figures 5.17a – 5.17h).

· Provision of Upgraded Glazing and Air-conditioners for Schools

Upgraded window glazing and air-conditioners should be provided to the affected noise-sensitive rooms of the schools, in addition to the recommended roadside noise barriers along Cha Kwo Ling Road. Window type I (as per EIAO-TM^[3]) with 6mm thick glass pane and well gasketted seals will be provided.

· The necessity of the Proposed WCR Semi-Enclosure & Barriers for WCR Coastal Option

Additional calculations have been performed to assess the WCR noise impacts if other means of noise reduction are to be taken. It is not considered viable to construct noise barriers with a practical height within the western site boundary for screening the WCR noise as the towers are of at least 39-storey high and the WCR is elevated. Further significant setback of the towers will not be possible with the site fully utilised by the proposed towers and schools.

Based on the results reported in Section 5.6, the percentage of exceedence of the residential development with semi-enclosure for the WCR is 2%. The proposed WCR semi-enclosure is essential for the Development as an unacceptably high 9% exceedence will result for the scenario without WCR semi-enclosure.

· Decking Over and Extended Podium

As all the surrounding roads are existing and are lying outside the site boundary, decking over these roads is considered not viable. However, in order to screen off part of the traffic noise, one storey podium has been proposed and extended up to the site boundary along Ko Fai Road and Cha Kwo Ling Road together with other noise mitigation measures including barriers, setback distance, non-openable windows (as indicated in Figures 5.6a to 5.6f) and podium design (as indicated in Appendix 5Q).

5.7 Aircraft Noise Assessment

5.7.1 The Development lies beyond the NEF25 contour of the Chek Lap Kok Airport. Hence, there will be no aircraft noise restrictions on the Development.

5.8 Industrial Noise Impacts on the Development

5.8.1 The possible industrial noise sources have been identified during the site surveys as the industrial buildings located at Ko Fai Road approximately 20m from the southern site boundary. The noise levels measured at the site boundaries were dominated by road traffic noise.

5.8.2 The separation between the rooftop condensers and the southern facades of the towers will be over 60m.

5.8.3 Yau Tong Industrial Area has been rezoned as R(E), C and GIC. However, some of the industrial sources might still be operating in the interim period while the Yau Tong Industrial Area is being re-developed. The predicted maximum noise levels at the nearest towers are 59dB(A) during day-time and 49dB(A) at night-time. These are within the stipulated (ANL-5) noise limits as explained in Section 5.3

5.8.4 In the event that Yau Tong Industrial Area remains unchanged and constitutes an Influence Factor, the predicted maximum noise levels at the nearest towers are 64dB(A) during day-time and 54dB(A) at night-time, which still comply with the stipulated noise limits for ASR of C.

5.8.5 The Development has minimized the adverse noise impact that would be caused by the Yau Tong Industrial Area in the south during the interim period by providing an adequate setback of the towers. It is therefore unlikely that the residents would be adversely affected by industrial noise.

5.8.6 Based on noise levels in the range of 47 – 49 dB(A) Leq measured at approximately 10m from the Salt Water Pumping Station, the predicted noise levels caused by the Pumping Station at the nearest NSR located at more than 30m away are within 41 dB(A) and fully complying with the stipulated noise limits.

5.9 Potential I/R Interface Impact on the Development

Noise Mitigation Measures Adopted in the Building Design

5.9.1 Effective noise mitigation measures will be employed by the Development to tackle the I/R interface noise problems. These measures include :-

· Careful layout

· Buffer zone

· Design of tall podium

· Use of podium parapet as additional noise screen

· Noise tolerant building design

· Use of noise tolerant structure to provide noise buffer

· Use of tall noise barriers

· Phasing of development

· Provision made for upgraded glazing and A/C units for flats.

Careful layout

5.9.2 The layout plans for WCR Coastal and Tunnel Options have been optimised so that the industrial premises will cause the minimum impact to residential blocks. Noise tolerant buildings such as office and shopping arcade will be provided as screens for YTML lots 73-74 and 25-27 so that the schools and residential towers will keep maximum setback distances from the industrial lots (Figures 5.3b and 5.3e).

Buffer Zone

5.9.3 Temporary open space will be provided as buffer zone to maximise the setback distances from the industrial lots (Figures 5.6b and 5.6e).

Noise tolerant building design

5.9.4 Noise tolerant building design has been employed for blocks located close to the industrial lots (Figures 5.6b and 5.6e).

Use of Noise tolerant structure to provide noise buffer

5.9.5 The Clubhouse, which will be provided with central A/C and adequate glazing systems, will be noise-tolerant and serving as a noise buffer to Blocks 36 and 37.

Design of tall podium and parapet as additional screen

5.9.6 The shopping arcades will provide 15m high podiums with useful noise screening for protecting the schools and residential towers from the industrial lots YTML 1, 2-4, 25, 26 and 27.

5.9.7 A 5m high podium will be employed such that the flats will be set back as much as practicable from the industrial lots. The use of a 1.2m high podium edge parapet will give an additional noise screening to reduce the industrial noise impact to the worst-affected flats at lower floors.

Use of tall noise barriers

5.9.8 Tall noise barriers with a practical height of 8m will be erected at suitable locations around the industrial lots, supplementing the podium deck in screening the industrial noise from affecting the worst-affected flats on the lower floors (Figures 5.17b and 5.17e).

Provision made for upgraded glazing and A/C units for flats

5.9.9 In order to reduce the external traffic noise impact on the occupants of the residential Development, upgraded glazing, i.e. window type I (as per EIA-TM[3], Annex 5 of Table 2) with glazing comprising minimum 6mm thick glass pane and well gasketted seal will be installed to the noise sensitive areas including bedrooms, living rooms and dining rooms of the affected flats. In addition, air-conditioners will be provided to all noise sensitive rooms of the flats so that the occupants will not solely rely on open windows for ventilation and that the adverse noise impact caused by external noise sources will be effectively reduced.

Methodology of Noise Impact Assessment due to the Remaining Industrial Lots

5.9.10 Computer models have been constructed to predict the facade noise levels at the worst affected NSRs near the industrial lots (Figure 5.18).

5.9.11 Calculations have been conducted based on 2 scenarios:-

· Existing scenario

- YTML 1: Sawmill

- YTML 2-4 (UDL): Shipyard

- YTML 25: Timber yard

- YTML 26: Dry goods storage

- YTML 27: Sawmill

- YTML 73-74 (Wing Shan Industrial Building): noise due to ventilation fans and exhaust lourves

· Worst scenario

- YTML 1: Sawmill

- YTML 2-4 (UDL): Sawmill

- YTML 25: Sawmill

- YTML 26: Sawmill

- YTML 27: Sawmill

- YTML 73-74 (Wing Shan Industrial Building): noise due to ventilation fans and exhaust lourves

Predicted Noise Impacts for Existing Scenario

5.9.12 With the assumption that the current industrial/office uses at YTML 73-74 (formerly known as Agincourt) and YTML 25-27 (storage and sawmill) remain unchanged in the case of industrial and residential co-existence, noise levels at the future NSRs in the Development have been predicted and presented in the following.

5.9.13 The predicted noise levels are 37-52 dB(A) at the schools and, 31-58 dB(A) during daytime and 16-47 dB(A) during night-time at the nearest NSRs of the residential blocks. These levels are within the (ANL - 5) limits during daytime and night-time as stipulated in Section 5.3. No residual noise impact will result with the adoption of the noise mitigation measures.

5.9.14 A summary of predicted noise levels is given in Appendix 5Ra with sample calculations for NSRs 11, 391, 211, 301, 342, 2001, 3002 and 3003 given in Appendix 5Rb.

Predicted Noise Impacts for Worst Scenario

5.9.15 With the worst assumption that YTML 1, 2-4 and 25-27 will be converted to sawmills (permitted use under the lease conditions) in the future, noise levels at the future NSRs in the Development have been predicted and presented in the following.

5.9.16 The predicted noise levels are 41-57 dB(A) at the schools and, 32-59 dB(A) during daytime and 16-47 dB(A) during night-time at the nearest NSRs of the residential blocks. These levels are within the (ANL - 5) limits during daytime and night-time as stipulated in Section 5.3. No residual noise impact will result with the adoption of the noise mitigation measures.

5.9.17 A summary of predicted noise levels is given in Appendix 5Sa with sample calculations for NSRs 11, 391, 211, 301, 342, 2001, 3002 and 3003 given in Appendix 5Sb.

5.10 Industrial Noise Impacts from the Development on the NSRs in the Vicinity

5.10.1 The plant noise control is essential as the A/C plantrooms and sewage pumping station in the proposed Development may need to be in operation during the evening (1900 to 2300 hours) and night (2300 to 0700 hours).

5.10.2 For the design of plant noise control treatment, the plant noise emanating from plantrooms and from the fresh air intake and discharge air grilles shall be controlled to 50 dB(A), measured at 1m from the affected facade of the NSRs in the vicinity and the Development. This will meet the (ANL-5) limit of 50 dB(A) during night-time. Provisions shall be made to control the plant noise by suitable silencers, acoustic louvres and enclosures.

5.10.3 It is also recommended that the air-handling units, fans, chillers, pumps and associated pipework services shall be isolated from the structure by steel spring vibration isolators in order to reduce structure-borne noise.

5.11 Environmental Monitoring and Audit (EM&A) Requirements

5.11.1 A stand-alone EM&A Manual has been developed to define the scope of the EM&A requirements for the construction and operation of the project to achieve satisfactory environmental performance.

5.11.2 With the implementation of mitigation measures, the predicted day-time construction noise levels are within the criteria stipulated in the EIAO-TM. However, a limited amount of day-time noise monitoring for 30 active minutes on a bi-weekly basis shall be carried out during the construction stage. The noise monitoring locations are proposed at the Eastern Harbour Crossing Site (Phase 2) (REHC2), Yau Tong Estate (Phase 1) (RYTE1) and new school at Yau Tong Estate (south) (RSCH2) (Figure 5.19).

5.12 Conclusion

Construction Phase

5.12.1 An assessment of construction noise was undertaken based on GW-TM. Noise exceedances have been predicted at the nearest NSRs for daytime period due to the Development construction.

5.12.2 With the implementation of the construction mitigation measures, including the use of quiet plants and movable noise barriers, the construction noise levels at the NSRs will comply with the statutory noise criteria. Regular monitoring of construction noise levels at representative NSRs is recommended to ensure that the NSRs will not be adversely affected by the construction noise.

Operational Phase

5.12.3 Traffic noise assessment has been conducted based on the Year 2030 traffic forecast for the WCR Coastal and Tunnel Options. The effectiveness of the Development’s proposals and mitigation measures are dependent to a large degree to the Administration’s commitment to mitigation measures on a WCR, if adopted.

5.12.4 Results indicate that only a minority (within 2%) of the residential flats of the 6 development scenarios and 2 options of Refined Scheme will be subject to traffic noise levels exceeding the 70dB(A) noise criterion. The schools will be subject to facade noise levels of 35 – 73dB(A) with some rooms facing onto Cha Kwo Ling Road exceeding the stipulated 65dB(A) noise criterion.

5.12.5 It has been recommended to erect 5m high roadside noise barriers along Cha Kwo Ling Road and 5m high podium edge barriers facing Ko Fai Road for the WCR Coastal and Tunnel Options. As a last resort, upgraded Type I glazing and air-conditioners have been recommended to be provided to all noise sensitive rooms of the affected residential flats and the noise sensitive rooms of the affected schools in the 8 development scenarios (including 2 options for Refined Scheme).

5.12.6 With the implementation of the above mitigation measures, the occupants of the proposed residential Development will not be adversely affected by road traffic noise for all 8 development scenarios.

5.13 References

[1] Environmental Protection Department "Technical memorandum on Environmental Impact Assessment Process”, September 1997 (EIAO-TM).

[2] Environmental Protection Department "Technical memorandum on noise from construction work other percussive piling", July 1991 (GW-TM).

[3] Environmental Protection Department "Technical memorandum on noise from construction work in designated areas", March 1996 (DA-TM).

[4] Environmental Protection Department "Technical memorandum on noise from percussive piling", June 1997 (PP-TM).

[5] Environmental Protection Department "Technical memorandum for the assessment of noise from places other than domestic premises, public places or construction sites", June 1997 (IND-TM).

[6] WS Atkins Noise and Vibration, England "RoadNoise 2000" computer software, 2000.

[7] Department of Transport, Welsh Office, UK "Calculation of Road Traffic Noise" 1988.