3 NOISE IMPACT

3.1 Introduction

3.1.1 Noise will be one of the key environmental issues in this Project. It is anticipated that noise from the use of powered mechanical equipment (PME) on site and the haulage of construction materials during the construction of the Project will cause a nuisance to the nearby noise sensitive receivers. During operation phase, road traffic noise would have significant noise impacts on the adjacent noise sensitive receivers if unmitigated.

3.1.2 This section presents a detailed noise assessment for the construction and operation phases of the Project. The representative noise assessment points to be affected by the Project are identified. The relevant noise legislation, assessment methodology, potential noise impacts together with an evaluation of noise mitigation measures aimed to alleviate the impacts are presented in this section.

3.2 Environmental Legislation, Policies, Plans, Standards and Criteria

General

3.2.1 Noise impacts have been assessed in accordance with the criteria and methodology given in the Technical Memoranda (TMs) under the Noise Control Ordinance (NCO), and the Technical Memorandum on Environmental Impact Assessment Process (EIA-TM).

3.2.2 The Noise Control Ordinance (Cap 400) (NCO) and the Environmental Impact Assessment Ordinance (Cap 499) (EIAO) provide the statutory framework for noise control. Guidelines concerning the assessment methodology and relevant criteria are provided in the supporting Technical Memoranda (TMs).

3.2.3 The following TMs are applicable to the control of noise from construction activities:-

l TM on Environmental Impact Assessment Process (EIA-TM)

l TM on Noise from Construction Work other than Percussive Piling (GW-TM)

l TM on Noise from Percussive Piling (PP-TM)

l TM on Noise from Construction Work in Designated Areas (DA-TM)

Construction Noise – Percussive Piling

3.2.4 Percussive piling is prohibited at any time on Sundays and public holidays and during the weekday evening and night-time hours (i.e. 1900 to 0700 hours, Monday through Saturday). A Construction Noise Permit (CNP) is required for such works during the weekday daytime hours (i.e. 0700 to 1900 hours, Monday through Saturday).

3.2.5 When assessing a CNP application for carrying out percussive piling, the Noise Control Authority is guided by the PP-TM. The Noise Control Authority will pay particular concern on the difference between the Acceptable Noise Levels (ANLs), as promulgated in the PP-TM and the Corrected Noise Levels (CNLs) that are associated with the proposed piling activities. Depending on the level of noise impact on nearby Noise Sensitive Receivers (NSRs), the Noise Control Authority would determine the time periods for percussive piling operation. The time periods are indicated in Table 3.1.

Table 3.1 Permitted Hours of Operation for Percussive Piling (not involving the use of diesel, pneumatic and/or steam hammers)

Amount by which CNL excceds ANL	Permitted hours of operation on any day not being a holiday
10 dB(A) < CNL-ANL	0800 – 0900 and 1230 – 1330 and 1700 - 1800
0 dB(A) < CNL-ANL £ 10 dB(A)	0800 – 0930 and 1200 – 1400 and 1630 - 1800
CNL-ANL £ 0 dB(A)	0700 – 1900

3.2.6 The Government is committed to phase out the use of diesel, pneumatic and steam hammer pile drivers which are particularly noisy. There are more stringent requirements for the use of diesel, pneumatic and steam hammer after 1 October 1999.

3.2.7 In this Project, percussive piling may be employed. The Contractor will apply for the Construction Noise Permit (CNP) if necessary. The Noise Control Authority will judge these at the time of CNP application.

Construction Noise – General Construction

3.2.8 Noise generated by general construction works during normal working hours (i.e. 0700 to 1900 hours on any day not being a Sunday or public holiday) fall within the scope of the EIA-TM. The recommended noise standards are presented in Table 3.2.

Table 3.2 EIA-TM Daytime Construction Noise Limit

Uses	Noise Standard (Leq 30min dB(A))
Domestic Premises	75
Educational Institutions (normal periods)	70
Educational Institutions (during examination periods)	65

The above standards apply to uses which rely on opened windows for ventilation.

Construction Noise – During Restricted Hours

3.2.9 The NCO provides statutory controls on general construction works during the restricted hours (i.e. 1900 to 0700 hours Monday to Saturday and at any time on Sundays and public holidays). The use of PME for the carrying out of construction works during the restricted hours would require a CNP. The Noise Control Authority is guided by the GW-TM when assessing such an application.

3.2.10 When assessing a CNP application for the use of PME, the Noise Control Authority will compare the ANLs as promulgated in the GW-TM, and the CNLs (after accounting for factors such as barrier effects and reflections) associated with the agreed PME operations. The CNP may be issued if the CNL is equal to or less than the ANL. The ANLs are related to the noise sensitivity of the area in question and the Noise Control Authority will judge these at the time of the CNP application. As conditions may vary between the time of the EIA for a project and the time of a CNP application, the assignment of any Area Sensitivity Ratings in the EIA is not binding upon the Noise Control Authority. The relevant ANLs are shown in Table 3.3.

Table 3.3 Acceptable Noise levels (ANL, Leq 5min dB(A))

Time Period	Basic Noise Levels
	ASR A	ASR B	ASR C
All days during the evening (1900-2300) and general holidays (including Sundays) during the day and evening (0700-2300)	60	65	70
All days during the night-time (2300-0700)	45	50	55

3.2.11 In addition to the general controls on the use of PME during the restricted hours, the Noise Control Authority has implemented a more stringent scheme via the DA-TM. The DA-TM regulates the use of five types of Specified Powered Mechanical Equipment (SPME) and three types of Prescribed Construction Work (PCW) which are non-PME activities, in primarily densely populated neighborhoods called Designated Areas (DAs) during restricted hours. The SPME and PCW are shown in Table 3.4.

Table 3.4 Specified Powered Mechanical Equipment and Prescribed Construction Work Controlled under DA-TM

Specified Powered Mechanical Equipment (SPME)	Prescribed Construction Work (PCW)
l Hand-held Breaker l Bulldozer l Concrete Lorry Mixer l Dump Truck l Hand-held Vibratory Poker	l Erection or Dismantling of Formwork or Scaffoldings l Loading, Unloading or Handling of Rubble, Wooden Boards, Steel Bars, Wood or Scaffolding Material l Hammering

3.2.12 In the interest of offering additional protection to the population, PCW is generally banned inside a DA during restricted hours. As for the use of SPME, it would be necessary to comply with DA-TM noise level requirements that are 15 dB(A) less than those listed in the GW-TM before a CNP may be issued.

3.2.13 Factors such as the assigning of Area Sensitivity Rating, ANLs etc could affect the assessment results of a CNP application. The Noise Control Authority would decide these at the time of assessment of such an application based on the contemporary situations/conditions. It should be noted that the situations/conditions around the sites may change from time to time.

3.2.14 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 Technical Memoranda issued under the Noise Control Ordinance. 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 deciding whether to grant a CNP. Nothing in this EIA Report should bind the Noise Control Authority in making its decision. If a CNP is to be issued, the Noise Control Authority should include in the permit any condition it thinks fit. Failure to comply with any such conditions will lead to cancellation of the CNP and prosecution under the NCO.

3.2.15 In case that the CNL exceeds the ANL, a CNP may be granted if it can be demonstrated to the satisfaction of the Authority that carrying out the construction work during restricted hours would cause less public annoyance or inconvenience than would be caused by carrying out the work during non-restricted hours.

Operational Noise – Traffic Noise

3.2.16 The EIA-TM provides guidance on acceptable road traffic noise levels at openable windows of various types of noise sensitive buildings. The relevant criteria are shown in Table 3.5.

Table 3.5 EIA-TM Road Traffic Noise Planning Criteria

Uses	Road Traffic Noise L10, (1hr) dB(A)
Domestic Premises	70
Hotel and Hostels	70
Offices	70
Educational Institutions	65
Places of Public Worship and Courts of Law	65
Hospital, Clinics and Homes for the aged	55
Note: The criteria presented in the above apply to noise sensitive uses which rely on opened window for ventilation

3.3 Description of the Environment

3.3.1 The existing noise environment in the vicinity of the Project area is dominated by the road traffic on the existing Tuen Mun Road, Pui To Road, Tuen Hing Road, Wong Chu Road and Castle Peak Road.

3.3.2 The existing land uses in the vicinity of the Project site are mainly for residential and recreational uses. Besides, there are some educational and GIC land uses scattered along the concerned roads.

3.4 Noise Sensitive Receivers

3.4.1 Existing NSRs including residential uses, places of worship, etc relying on opened windows for ventilation and educational institutions within 300m of study area were identified in accordance with Section 3 of Annex 13 of the EIA-TM.

3.4.2 There is an open storage area adjacent to the CSBS (Mrs. Aw Boon Haw Secondary School). The land use is zoned as GIC area under the Tuen Mun Outline Zoning Plan S/TM/24 and no planning application for change of land use was found on the website (http://www.ozp.tpb.gov.hk/default.aspx) for e-Planning Archives of Planning Department in July 2008. A site office for this Project will be located at this open storage area.

3.4.3 By considering the acoustic shielding of the front layer receivers, the existing representative NSRs were identified for noise assessment with reference to topographic maps and field surveys. For the purpose of the noise assessment, a number of representative NSRs which were considered to be potentially worst-affected were selected and has been agreed with EPD (The relevant correspondence letter is attached in Appendix 3.1). Photographs of all the identified existing NSRs are provided in Appendix 3.2. The representative NSRs for construction and traffic noise assessments are summarised in Tables 3.6 below. Their locations are illustrated in Figures 3.1A to 3.1C.

Table 3.6 Representative NSRs for Noise Assessments

NSR	Description	Use	Traffic Noise Criteria dB(A)	No. of Storey
TMC	Tuen Mun Church	Place of worship	65	6
PAC	Parkview Court	Residential	70	28
ELC	ELCHK Tuen Mun Lutheran Church Dzwen Sheng Tang Kindergarten	School	65	3
YLB 1	Yik Lee Building	Residential	70	5
YLB 2	Yik Lee Building	Residential	70	2
PEN	PEN Church of Hong Kong Sheltered Workshops and Hostel	GIC	70	3
KHB	Kam Hing Building	Residential	70	25
EC1	Eldo Court	Residential	70	24
EC2	Eldo Court	Residential	70	24
RDG	Rose Dale Garden	Residential	70	25
FEC *	Far East Consortium Tuen Mun Central Building	Residential	70	10
HFB	Hing Fat Building	Residential	70	15
OC	Orchid Court	Residential	70	16
FM *	Forward Mansion	Residential	70	11
HTB *	Hing Tai Building	Residential	70	8
FHB	Fu Hang Building	Residential	70	5
MSB	Man Shing Building	Residential	70	14
SC	Sun Court	Residential	70	14
TMTP1 *	Tuen Mun Town Plaza	Residential	70	27
TMTP2	Tuen Mun Town Plaza	Residential	70	27
TMTP3	Tuen Mun Town Plaza	Residential	70	27
TMTP4	Tuen Mun Town Plaza	Residential	70	29
TMTP5	Tuen Mun Town Plaza	Residential	70	27
TMTP6	Tuen Mun Town Plaza	Residential	70	27
WG1	Waldorf Garden	Residential	70	26
WG2 *	Waldorf Garden	Residential	70	26
NTM1	New Town Mansion	Residential	70	22
NTM2	New Town Mansion	Residential	70	22
CMA *	CMA Choi Cheung Kok Secondary School	School	65	6
LWF *	Yan Oi Tong Madam Lau Wong Fat Primary School	School	65	7
THC1	Ting Hoi Court	Residential	70	17
THC2	Ting Hoi Court	Residential	70	17
TMF *	Tuen Mun Fa Yuen	Residential	70	17
LCK *	Lui Cheung Kwong Lutheran College	School	65	6
LPB	Lee Bo Building	Residential	70	28
LBB	Lai Bo Building	Residential	70	27
CLFY1 *	Chi Lok Fa Yuen	Residential	70	16
CLFY2	Chi Lok Fa Yuen	Residential	70	15
CLFY3	Chi Lok Fa Yuen	Residential	70	16
CLFY4	Chi Lok Fa Yuen	Residential	70	15
CLFY5	Chi Lok Fa Yuen	Residential	70	15
CLFY6	Chi Lok Fa Yuen	Residential	70	15
TFH *	On Ting Estate ( Ting Fuk House)	Residential	70	27
LCKP *	Lui Cheung Kwong Lutheran Primary School	School	65	7
RG	Rainbow Garden	Residential	70	18
HKG	Hong King Garden	Residential	70	18
TTP *	Tung Wah Group of Hospitals Tai Tung Pui Social Service Building	GIC	55 / 70 ^#	11
JCP	JC Place	Residential	70	18
CSBS *	CSBS Mrs. Aw Boon Haw Secondary School	School	65	6
HG	Harvest Garden	Residential	70	17
HFDG	Hanford Garden	Residential	70	26
SSE	Sam Shing Estate	Residential	70	27
SST	Sam Shing Temple	Temple	65	1
KFG1A	Kam Fai Garden	Residential	70	15
KFG1B	Kam Fai Garden	Residential	70	15
KFG2A	Kam Fai Garden	Residential	70	15
KFG2B	Kam Fai Garden	Residential	70	15
KFG2C	Kam Fai Garden	Residential	70	15
KFG2D	Kam Fai Garden	Residential	70	15
KFG3A	Kam Fai Garden	Residential	70	15
KFG3B	Kam Fai Garden	Residential	70	15
KFG3C	Kam Fai Garden	Residential	70	15
KFG3D *	Kam Fai Garden	Residential	70	15
KFG4A	Kam Fai Garden	Residential	70	15
KFG4B	Kam Fai Garden	Residential	70	15
SHT	Tuen Mun Sin Hing Tong	Temple	65	2
SLC1	Po Lun House, Siu Lun Court	Residential	70	35
SLC4	Sui Lun House, Siu Lun Court	Residential	70	35

Remark:

* NSRs with asterisk are representative NSRs assessed for both traffic noise impact and construction noise impact; others are assessed for traffic noise impact only.

^# The noise criteria of TTP for 1F to 4F is 55 dB(A).

3.5 Assessment Methodology

Construction Noise

3.5.1 Construction noise impact was assessed by adopting the standards acoustic principles and the methodologies relevant to technical memoranda issue under the Noise Control Ordinance, primarily the GW-TM.

3.5.2 During daytime from 0700 to 1900 hours on weekdays other than general holidays, the assessment of construction noise was carried out in accordance with the methodology stipulated in paragraphs 5.3 and 5.4 of Annex 13 and the criteria in Table 1B of Annex 5 of the EIA-TM.

3.5.3 Sound Power Levels (SWLs) of the equipment were taken from Table 3 of the GW-TM. The assessment also made reference to the British Standards BS 5228: Part 1:1984 Noise Control on Construction and Open Sites, Part1: Code of Practice for Basic Information and Procedures for Noise Control. Sound power levels of equipment will be made reference to these TMs and the BS5228, where applicable, and the emission levels in previous projects in Hong Kong would also be referred.

3.5.4 Schedules of powered mechanical equipment (PME) for different construction tasks of the Project and other concurrent construction activities of other projects during normal daytime working hours are presented in Appendix 3.3. The Project Proponent has confirmed that the plant inventory is valid for the Project works.

3.5.5 It was assumed that all PME items required for a particular construction activity would be located at the notional or probable source position of the segment where such activity is to be performed. The assessment was based on the cumulative SWL of PME likely to be used for each location, taking into account the construction period in the vicinity of the receiver location. To predict the noise level, PME was divided into groups required for each discrete construction task. The objective was to identify the worst case scenario representing those items of PME that would be in use concurrently at any given time. The sound pressure level of each construction task was calculated, depending on the number of plant and distance from receivers. The noise levels at NSRs were then predicted by adding up the SWLs of all concurrent construction tasks.

3.5.6 A positive 3 dB(A) façade correction was added to the predicted noise levels in order to account for the facade effect at each NSR.

3.5.7 Accordingly the unmitigated construction noise impacts at the identified NSRs were predicted. Practicable direct mitigation measures including use of quieter equipment, movable barriers, enclosures and quieter alternative methods were recommended if exceedance of relevant criteria was predicted. In case where the mitigated noise levels still exceeded the relevant criteria, the duration of the noise exceedance would be estimated.

3.5.8 The construction of the Project is originally to be commenced in late 2008 and completed by 2010. Due to a number of factors and various design developments, the commencement of the Project is postponed and the completion date will be delayed to 2012. Details of construction tasks are as follows:

l Site clearance, fencing & hoarding;

l Construction of a flyover and modification to existing flyover;

l Demolition of 4 existing footbridges and construction of 4 new footbridges;

l At grade road widening, i.e. demolition of existing verges, kerbs, central reserves, excavation works, minor slopeworks, realign the kerb, etc;

l Road paving and road marking;

l Construction of noise barrier and noise enclosures;

l Landscape works; and

l Tree transplantation and compensation works.

3.5.9 As the road widening works are to be undertaking on existing Tuen Mun Road, working space for the works is limited. It is anticipated that the works will be conducted in batches progressively with maximum of 170m works front at a time. The above construction activities would not be taken place concurrently.

3.5.10 The programme of the Project may overlap with the project of “Widening of Tuen Mun Road at Tsing Tin Interchange” which commenced in June 2008 and would be completed in 2010. However, the separation distance between both projects boundary would be more than 300m, cumulative noise impacts are therefore not expected.

3.5.11 The portion of project site of “Reconstruction and Improvement of Tuen Mun Road - Sam Shing Hui Section, Contract No.HY/2008/11” near Kam Fai Garden is planned to be commenced in mid 2009 and completed by end 2010. The Tuen Mun Town Centre Project is planned to be commenced in end 2009. Upon the completion of the works, this portion of the site would be handover to the Tuen Mun Town Centre Project for construction works. The works for Tuen Mun Town Centre Project from end 2009 to end 2010 would be mainly tree transplantation and felling works. It is anticipated that there would be no overlapping of major construction activities of both projects.

3.5.12 Noise sources from the areas greater than 300m of a given NSR are excluded from the assessment.

Operation Noise

3.5.13 Traffic noise was predicted using the methodology provided in the UK Department of Transport Calculation of Road Traffic Noise (CRTN) 1988. All noise levels were expressed in terms of L_10(1-hour) dB(A). The value of L_{10 (1-hour)} dB(A) is the noise level exceeded for just 10% of the time over a period of one hour. For comparison with the specified noise level or the EIA-TM standards, the relevant noise level from traffic was to be rounded to the nearest whole number (0.5 being rounded up).

3.5.14 Considering the scope of this Project, road sections were classified as the following categories for purpose of road traffic noise assessment:-

l ‘New’ Roads - roads within the meaning of Item A.1, Part I, Schedule 2 of the EIAO) that are completely new or major modification to an existing road sections resulting in 25% increase in lanes or substantial changes in alignment or characters of the road due to the proposed Project. In this Project, whole section of the Tuen Mun Road within the Project boundary is identified as new road with the exception of the realigned sections of Tsing Hoi Circuit and a small portion near the northern end. Sensitivity tests for aforesaid sections have been carried out and the results demonstrating that there is no adverse traffic noise impact to the nearby NSRs in accordance with the EIA-TM. Results of the sensitivity test are given in Appendix 3.9.

l ‘Existing’ Roads - that is, roads that are unchanged or subject to minor changes (i.e. less than 1.0 dB(A) noise contribution from the improved road to the overall noise level) by the Project except for possibly taking additional traffic.

3.5.15 The ‘New’ roads defined for the assessment are shown in Figures 3.2A to 3.2C.

3.5.16 As mentioned in Section 2.6.2, the Project is originally to be completed in 2010 but now is postponed to 2012. As a result from the change of completion date to 2012, a review on the traffic figures adopted in this assessment has been carried out. The 2025 traffic forecast endorsed by TD for use in this assessment was derived from the 2003-based TPEDM SI planning data. However, this set of planning data is now superseded by the 2006-based TPEDM SI planning data which was released by PlanD in mid 2008. Comparing the 2027 population and employment data in NWNT from the 2006-based TPEDM SI against the assumed 2025 population and employment data adopted in the 2025 traffic forecast, the 2027 figures obtained from the 2006-based TPEDM SI planning data are even smaller than the assumed 2025 figures adopted in the 2025 traffic forecast which were developed with reference to the 2003-based TPEDM SI planning data. There are some reductions in population and employment assumptions in the 2006-based TPEDM SI planning data. Since the traffic flows on TMRTCS are in proportion to the population and employment of NWNT (i.e. Tuen Mun/Tin Shui Wai/Yuen Long areas), the endorsed 2025 traffic forecast for the EIA are derived from a set of relatively higher population and employment assumptions. Hence even the assessment year of the EIA is postponed to 2027 and the traffic forecast for the EIA is to be updated with the latest set of 2006-based TPEDM SI planning data, the 2027 traffic forecast so produced would still be anticipated to be less than the endorsed 2025 traffic forecast. Therefore, adoption of endorsed 2025 traffic figure in the assessment is on a conservative side.

3.5.17 Apart from the traffic noise after completion of the road improvement works, prevailing traffic noise level (based on the traffic data at 2008 before project commencement) have also been assessed for eligibility test for noise insulation works. The projected 2025 peak hour traffic flows and 2008 prevailing traffic flow data are presented in Appendix 3.4. The agreement letter from Transport Department on the use of the projected traffic data for this Study is attached in Appendix 3.4.

3.5.18 The unmitigated traffic noise levels at the selected NSRs were predicted. If an exceedance of noise limit at any NSR occurred, noise mitigation measures would be considered to alleviate the traffic noise impact.

3.5.19 Direct mitigation measures would be proposed for ‘New’ roads (i.e. within the meaning of Item A.1 of Schedule 2 of EIAO-TM) if there would be an adverse environmental impact. If the NSRs are affected by noise from other existing roads, direct mitigation measures are required to reduce the noise from the ‘New’ roads to a level that it:-

l is not higher than the noise standard; and

l has no significant contribution to the overall noise from other existing roads, if the cumulative noise level (i.e. noise from the new road together with other existing roads) exceeds the noise standard.

3.5.20 If any facades of existing NSRs are still exposed to predicted noise levels exceeding the relevant noise criteria after implementation of all feasible direct mitigation measures, provision of indirect technical remedies in the form of acoustic insulation and air conditioning should be considered under the EIAO GN 12-2005, “Road Traffic Noise Impact Assessment Under the Environmental Impact Assessment Ordinance”. Eligibility for indirect technical remedies will be tested against the following three criteria:-

l The predicted overall noise level, L_10(1-hour), from the “New” road, together with other traffic noise in the vicinity must be above 70 dB(A) for domestic premises and 65 dB(A) for educational institutions;

l The predicted overall noise level is at least 1.0 dB(A) more than the prevailing traffic noise level; and

l The contribution to the increase in the predicted overall noise level from the “New” road must be at least 1.0 dB(A).

3.5.21 The total number of existing dwellings, classrooms and other noise sensitive elements that may be qualified for indirect technical remedies are then estimated.

3.6 Identification of Impacts

Construction Phase

3.6.1 Potential construction noise impacts may arise from the construction works outlined in previous section.

Operation Phase

3.6.2 Road traffic noise will arise from the new roads constructed or modified under the Project and the adjacent existing roads.

3.7 Prediction and Evaluation of Impacts

Construction Phase

3.7.1 As illustrated in the preliminary construction programme attached in Appendix 3.5, some of the construction activities would be carried out concurrently. In order to predict the noise level in the worst case scenario, the cumulative effect arising from those concurrent and relative construction activities were assessed at each representative NSRs. The programme shown on Appendix 3.5 represents the worst case scenario for the construction noise assessment. For other programme arrangements, such as longer construction periods of different construction activities, less cumulative noise impact is expected.

3.7.2 In the absence of any mitigation measures, it was found that the predicted noise levels at all representative NSRs were higher than the relevant construction noise criteria. The calculated results are summarized in Table 3.7. Detailed calculations of the unmitigated construction noise levels are presented in Appendix 3.6A.

3.7.3 In order to alleviate the construction noise impacts at the affected NSRs, mitigation measures such as adoption of quiet PME or use of movable noise barriers are required.

Table 3.7 Unmitigated Construction Noise Levels at Representative NSRs During Normal Daytime Working Hours

NSR	Description	Unmitigated Construction Noise Levels*, dB(A)
FEC	Far East Consortium Tuen Mun Central Building	75 – 89
FM	Forward Mansion	82 – 89
HTB	Hing Tai Building	80 – 90
TMTP1	Tuen Mun Town Plaza	66 – 91
WG2	Waldorf Garden	71 – 87
CMA*	CMA Choi Cheung Kok Secondary School	67 – 85
LWF*	Yan Oi Tong Madam Lau Wong Fat Primary School	72 – 85
TMF	Tuen Mun Fa Yuen	68 – 91
LCK*	Lui Cheung Kwong Lutheran College	64 – 90
CLFY1	Chi Lok Fa Yuen	77 – 91
TFH	On Ting Estate ( Ting Fuk House)	73 – 90
LCKP*	Lui Cheung Kwong Lutheran Primary School	67 – 85
TTP	Tung Wah Group of Hospitals Tai Tung Pui Social Service Building	84 – 91
CSBS*	CSBS Mrs. Aw Boon Haw Secondary School	72 – 83
KFG3D	Kam Fai Garden	82 – 89

* Remark: Boldfaced value presents the predicted noise level exceed the relevant noise limit. NSR with asterisk means educational institution.

Operation Phase

3.7.4 Based on the predicted peak hour traffic flows in 2008 and 2025, the prevailing traffic noise levels prior to the commencement of the Project and the unmitigated future traffic noise levels after completion of the Project at the representative NSRs were calculated.

3.7.5 The prevailing and unmitigated noise levels at the representative NSRs are provided in Appendix 3.7A.

3.7.6 The unmitigated noise levels in year 2025 for place of worship, residential and schools developments are in the ranges of 67.6 to 81.4 dB(A), 61.0 to 84.7 dB(A) and 70.8 to 83.8 dB(A) respectively. Most of the identified NSRs would expose to high noise levels exceeding the noise standards due to both the ‘New’ road and existing roads. The severe traffic noise impact is due to the high traffic volume and percentage of heavy vehicles as well as the close proximity of the nearby NSRs to the road alignments. Noise mitigation measures on ‘New’ roads are required to alleviate the adverse traffic noise impact.

3.8 Mitigation of Adverse Impacts

Construction Noise

3.8.1 Good site practice and management can significantly reduce the noise impact of construction site activities on nearby NSRs.  The following package of measures should be followed throughout the construction period:

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

l machines and plant that may be in intermittent use should be shut down between work periods or should be throttled down to a minimum;

l plant known to emit noise strongly in one direction should, where possible, be orientated to direct noise away from the NSRs;

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

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

3.8.2 The following sections describe measures which may be considered to reduce noise to the construction noise limits.

3.8.3 Mitigation measures are proposed to be implemented in three levels, namely Level 1, which involves adoption of quiet PME; Level 2, which involves provision of movable noise barrier; and Level 3, which involves scheduling of construction activities.

Level 1

Adoption of Quiet PME

3.8.4 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 taken from a British Standard, namely Noise Control on Construction and Open Sites, BS 5228: Part 1: 1997, which are known to be used in the assessment is given in Table 3.8.

Table 3.8 Listing of Quiet PME Items

Quiet Powered Mechanical Equipment (PME)	Identification Code / BS5228	Maximum SWL, dB(A)
Excavator	C8/33	102
Crane	C7/114	101
Truck	C3/59	105
Concrete Truck	C6/35	100
Poker Vibrator	CNP 173	102
Asphalt Paver	C8/24	101
Roller, vibratory	C3/115	102

3.8.5 With the use of quiet plant, the predicted noise levels at the NSRs in some months would still exceed the noise criteria. Detailed calculations of the construction noise levels at the NSRs with adoption of Level 1 mitigation measures are given in Appendix 3.6B.

Level 2

Use of Movable Noise Barrier

3.8.6 After adoption of Level 1 mitigation measures, the predicted construction noise at some representative NSRs during construction period would still exceed the relevant noise limits. Therefore, it is proposed to enhance the noise mitigation by provision of movable noise barrier.

3.8.7 Movable barriers could be effective in screening noise of particular items of plant such as poker vibrator and circular saw from reaching the NSRs.  A noise barrier located close to the noise generating component of a PME could produce at least 10 dB(A) screening for stationary plant and 5 dB(A) for mobile plant, depending on the line of sight that could be blocked by the barriers when viewed from the NSRs.

3.8.8 These noise barriers should be free of gaps and made of materials having a surface mass density of at least 15 kg/m². To improve the effectiveness of noise reduction, absorptive lining can be adhered on the inner surface of the barrier. The barrier can be in the form of vertical or bend top barrier with an effective height of 3m or above. Its length should be long enough to cover the length of the PME being protected. It is better to extend both ends of the barrier to exceed the size of the PME by a distance equal to the separation between the barrier and the PME.

3.8.9 With the implementation of the above mitigation measures, the mitigated construction noise levels were predicted. Detailed calculations of the mitigated construction noise levels are presented in Appendix 3.6C.

Table 3.9 Level 2 Mitigated Construction Noise Levels at Representative NSRs During Normal Daytime Working Hours

NSR	Description	Max Mitigated CNLs, dB(A)
FEC	Far East Consortium Tuen Mun Central Building	73
FM	Forward Mansion	73
HTB	Hing Tai Building	74
TMTP1	Tuen Mun Town Plaza	74
WG2	Waldorf Garden	71
CMA*	CMA Choi Cheung Kok Secondary School	69
LWF*	Yan Oi Tong Madam Lau Wong Fat Primary School	68
TMF	Tuen Mun Fa Yuen	75
LCK*	Lui Cheung Kwong Lutheran College	74
CLFY1	Chi Lok Fa Yuen	75
TFH	On Ting Estate ( Ting Fuk House)	74
LCKP*	Lui Cheung Kwong Lutheran Primary School	70
TTP	Tung Wah Group of Hospitals Tai Tung Pui Social Service Building	75
CSBS*	CSBS Mrs. Aw Boon Haw Secondary School	66
KFG3D	Kam Fai Garden	73

Remark:

NSR with asterisk means educational institution.

Boldfaced value presents the predicted noise level exceed the relevant noise limit.

Bold and italic value presents the predicted noise level exceed the noise limit for school during examination periods.

3.8.10 Based on the results shown in Table 3.9, the predicted construction noise levels at all residential NSRs would comply with the noise standard stipulated in the EIA-TM. However, the predicted construction noise level at education institute NSR LCK would exceed the noise limit by 4 dB(A) during the normal teaching period.

3.8.11 The predicted construction noise levels at five representative NSRs of educational institutions, namely CMA, LWF, LCK, LCKP and CSBS would also exceed the noise standard of 65 dB(A) by 1 to 9 dB(A) during examination periods.

Level 3

Scheduling of some Construction Activities

3.8.12 In order to further diminish construction noise impacts at NSR LCK, it is proposed that site clearance and the following activities at stage 2 (Ch. 28050 – 28200 of TMR) not to be undertaken in the vicinity of this NSR during normal teaching hours. With the implementation of these mitigation measures, the predicted noise levels at NSR LCK during normal teaching period would comply with the noise criterion of 70 dB(A). Detailed calculations of the mitigated construction noise levels are presented in Appendix 3.6D

· Truck would not operate concurrently with other PMEs during tree transplanting and noise barrier foundation work.

· Tree Transplanting would not be undertaken concurrently with Bulk Excavation and Utilities Diversion.

· Construction of Storm Water Drain would not be undertaken concurrently with Noise Barrier/Enclosure Foundation.

· Construction of Sub-base and Road Base would not be undertaken concurrently with Noise Barrier/Enclosure Installation.

· Road Surfacing, Construction of Road kerbs, Central Dividers, Parapets, and Installation of Crash Cushion and Sign Gantry would not be undertaken concurrently.

· Installation of Gantry and Directional Lighting, and Street Lighting would not be undertaken concurrently.

3.8.13 In order to avoid or reduce the construction noise problems at the schools (i.e. NSR CMA, LWF, LCK, LCKP and CSBS) during examination periods, the Contractor of the Project would be suggested to liaise with all the relevant schools to check out their examination periods and activities for preparation of the works programme. The noise calculations as presented in Appendix 3.6D demonstrate that these educational institutes would comply with the noise criterion during examination period with the scheduling of noisy construction activities. These mitigation measures are as a reference only, the Contractor can make good planning and arrangement of works and provide sufficient mitigation plans to alleviate the noise impacts.

Operation Noise

3.8.14 As mentioned in Section 3.5, direct mitigation measures should be considered or proposed on road project under the subject DP such that the noise from the “New” road to a level that it is not higher than the relevant standards and has no significant contribution to the overall noise from other existing roads. Based on this principle, mitigation measures are proposed.

Mitigation Measures

3.8.15 Noise mitigation measures in form of vertical barriers, cantilever barriers, partial enclosure or full enclosures have been considered in order to reduce the excessive noise impacts on the sensitive receivers arising from the Project. The proposed noise screening structures are mainly reflective type with transparent panels to reduce the visual intrusion and will be supported at structural steel frames fixed on concrete parapets. These noise barriers will have absorptive panels at the lower portion (about 1.5m). An enhanced low noise surfacing to the standard low noise surfacing (i.e. 30mm thick with aggregate size of 10mm) will be applied on the portion of carriageway as indicated on Figures 3.4A and 3.4B. This enhanced low noise surfacing could either be (1) 30mm thick low noise surfacing of smaller aggregate size (i.e. aggregate size < 10mm) or (2) thicker low noise surfacing of similar aggregate size (thickness > 30mm).

3.8.16 Layouts of proposed noise mitigation measures are presented in Figures 3.3A to 3.3C and summarized as below. These noise barriers should be designed and constructed to comply with the Guidelines on Design of Noise Barriers, March 2001, by Environmental Protection Department and Highways Department.

3.8.17 With the recommended noise mitigation measures, the mitigated traffic noise levels were calculated. The mitigated noise levels at the affected NSRs are provided in Appendix 3.7A.

3.8.18 With the proposed direct mitigation measures in place, the predicted overall noise levels at some NSRs would still exceed the relevant noise limits due to the noise contributions from existing roads or noise contribution from the “New” road (i.e. the noise levels from new roads at some NSRs still exceed the noise standards and/or the ‘New’ road noise contributions to the overall noise levels exceed 1.0 dB(A)). Taking into account of engineering, site and safety (e.g. fire services requirements) constraints, the proposed noise barrier/enclosures cannot be further extended, all direct noise mitigation measures are exhausted. The engineering and site constraints in limiting the design of noise barriers are given in Section 3.9.

3.8.19 The affected residential NSRs with exceedance of noise standards contributed from the “New” roads are summarized in Table 3.10.

Table 3.10 NSRs with Overall NLs Exceeding Noise Criteria and Contribution from ‘New’ Road NLs to Overall NLs Exceeding 1.0 dB(A)

NSR	Description	Contribution to Overall Noise Levels from		Mitigated Overall Noise Levels dB(A)
		Unmitigated New Road Noise	Mitigated New Road Noise
CLFY2	Chi Lok Fa Yuen	7.3 – 7.8	0.2 – 3.4	72.7 – 75.6
CLFY3	Chi Lok Fa Yuen	10.2 – 10.9	0.0 – 2.5	71.1 – 72.0
CLFY5	Chi Lok Fa Yuen	8.5 – 10.5	0.0 – 4.1	72.7 – 74.5
CLFY6	Chi Lok Fa Yuen	13.1 – 15.4	0.2 – 6.5	67.9 – 73.7
TFH	On Ting Estate (Ting Fuk House)	8.5 – 13.8	2.0 – 3.9	63.4 – 74.3
HKG	Hong King Garden	4.7 – 9.7	1.0 – 1.8	67.7 – 75..8
TTP	Tung Wah Group of Hospitals Tai Tung Pui Social Service Building	5.4 – 10.2	0.7 – 3.1	65.8 – 72.4
JCP	JC Place	5.3 – 6.8	0.5 – 1.5	70.0 – 72.3
HG	Harvest Garden	5.2 – 8.8	0.2 – 2.3	72.5 – 73.0
KFG1A	Kam Fai Garden	10.1 – 13.8	0.4 – 4.8	67.5 – 72.9
KFG1B	Kam Fai Garden	9.7 – 13.2	0.2 – 4.0	68.8 – 73.5

3.8.20 An eligibility test for indirect technical remedies was conducted for these NSRs to consider if provision of acoustic insulation and air conditioning is required. The results of the eligibility test are given in Appendix 3.7B.

3.8.21 Results of the eligibility test reveals that the NSRs are not eligible for provision of indirect technical remedies.

3.9 Evaluation of Residual Impacts

Construction Noise

3.9.1 With the implementation of the recommended noise mitigation measures, the cumulative construction noise impacts at all representative NSRs except some educational institutes such as NSR CMA, LWF, LCK, LCKP and CSBS during examination periods were predicted to be within the construction noise guidelines as stipulated in the EIA-TM.

3.9.2 In order to avoid or reduce the construction noise problems at the schools during examination, the Contractor of the Project is suggested to liaison with all the relevant schools to check out their examination periods and activities in the beginning of the work programme. Thus, the Contractor can make good planning and arrangement of works and provide sufficient mitigation plans to alleviate the noise impacts.

Operation Noise

3.9.3 With the implementation of the proposed mitigation, the overall noise levels at NSR FEC, OC, TMTP2, TMTP3, TMTP5, WG1, LCK, LPB, LBB, RG, SST, KFG2A, KFG2B, KFG2C, KFG2D, KFG3B, KFG3C, KFG3D and SLC1 are within the noise criteria. No residual impact is expected at these NSRs.

3.9.4 The overall noise levels at the residential premises including NSR PAC, YLB1, YLB2, KHB, EC1, EC2, RDG, HFB, FM, HTB, FHB, MSB, SC, TMTP1, TMTP4, TMTP6, WG2, NTM1, NTM2, THC1, THC2, TMF, CLFY1, CLFY4, HFDG, SSE, KFG3A, KFG4A, KFG4B and SLC4, schools including NSR ELC, CMA, LWF, LCKP, CSBS and other uses such as NSR TMC, PEN and SHT would exceed the relevant noise criteria. However, the ‘New’ road noise levels are within the noise criteria and no adverse noise impact is arising from the ‘New’ roads. Noise exceedances at these NSRs are mainly due to the existing roads.

3.9.5 The overall noise levels at NSR CLFY3 (mid to high floors), JCP and HG would exceed the traffic noise criterion. The ‘New’ road noise levels at these NSRs are all within the noise criterion (70dB(A)) but the “New” road contribution to the overall noise level would be greater than 1 dB(A).

3.9.6 For the mid to high floors of NSR CLFY3, the noise exceedances would be dominantly contributed from the elevated Tuen Mun Road section. However, no further direct mitigation measure on the “New” roads is allowed due to site constraint.

3.9.7 The major noise sources at NSR JCP and HG comes from the existing road of Castle Peak Road – Castle Peak Bay Section which is in front of the JC Place and Harvest Garden and the bridge section of Tuen Mun Road which across the Hoi Wing Road and Castle Peak Bay Section of Castle Peak Road. There is no upgrading work for this bridge section of Tuen Mun Road under this Project. Its existing foundation cannot take into account of additional loadings of noise barrier/enclosure. Therefore, installing noise barriers or enclosure along this strip of land is considered not feasible and remained as an open section.

3.9.8 With the proposed direct noise mitigation measures in place, noise exceedance would still be predicted at NSR CLFY2, CLFY5, CLFY6, TFH, HKG, TTP, KFG1A and KFG1B. The exceedance would be due to the traffic noise coming from the “New” road sections that could not be screened by proposed direct mitigation measures due to site constraint.

3.9.9 The “New” road noise levels at NSR CLFY2, CLFY5, CLFY6, HKG and TTP would exceed the 70dB(A) criterion. The majority of the noise impact comes from the unscreened elevated road section running towards southern direction (between Ch28160 and Ch28200). This section of road belongs to the existing Tuen Mun Road and Wong Chu Road Upramp. The elevated Wong Chu Road structure was built in 1980s’ and has not been designed for any additional future loadings for massive structures such as noise barriers or enclosure. Based on preliminary assessment, the current Wong Chu Road Flyover is already an optimal design and there is not enough spare capacity to support the loading induced by installing new noise barriers or enclosure. Therefore, installing noise barriers or enclosure on this structure is technically infeasible. For narrow strip between the Wong Chu Road Upramp and the Tuen Mun Road, in order to provide adequate horizontal clearance between the existing Tuen Mun Road and the existing Wong Chu Road Abutment, there will be not enough room to install barriers along this narrow strip of land while maintaining adequate clearance. Therefore, again, installing noise barriers or enclosure along this strip of land is considered not feasible. For this section, other than the portion of the roads between the Wong Chu Road Flyover and TMR KLN/B, all practicable mitigation measures near Wong Chu Road section have been explored. For the section near Kam Fai Garden, please note that all practicable mitigation measures near this section have been explored as well.

3.9.10 The “New” road noise levels at NSR TFH would exceed the 70dB(A) criterion. The dominant noise contribution in the “New” road noise levels would also come from the unscreened elevated road section running towards southern direction (between Ch28160 and Ch28200). No further noise mitigation measure is considered due to the site constraints as mentioned in S3.9.9. The noise contribution in the “New” road noise levels from partial open road section (Southbound of TMR) in the vicinity of Lai Po Building is insignificant. The overall noise reduction is less than 1 dB(A) even though covering this road section. In view of ineffective acoustic reduction, no further noise mitigation measure could be proposed for this road section.

3.9.11 Exceedance of “New” road noise levels at NSR KFG1A and KFG1B is due to the noise emitted from the “New” road section in front of Kam Fai Garden. Noise barriers have to be erected at Tuen Mun Road section above the Castle Peak Road or otherwise the noise could not be screened. However, this section of the road is an existing elevated structure (Sam Shing Hui Bridge) crossing Castle Peak Road. The elevated structure has not been designed for any additional future loadings for massive structures such as noise barriers or enclosure. Based on a preliminary assessment, the current structure is already an optimal design and there will be no enough spare capacity to support the loading induced by installing new noise barriers or enclosure. Therefore, installing noise barriers or enclosure on this structure is technically not feasible. For this section, other than the section of the road on the existing Sam Shing Hui Bridge, all practicable mitigation measures near this section have been explored.

3.9.12 The eligibility test in Appendix 3.7B shows that none of the representative NSRs is eligible for consideration for indirect technical remedies in the form of acoustic insulation and air conditioning under the EIAO GN 12-2005, “Road Traffic noise Impact Assessment under the Environmental Impact Assessment Ordinance”.

3.9.13 The number of dwellings or classrooms being protected or benefited from proposed noise mitigation measures are estimated and summarized in Appendix 3.8.

3.10 Monitoring and Audit Requirements

Construction Noise

3.10.1 An EM&A programme is recommended to be established according to the predicted occurrence of noisy activities. All the recommended mitigation measures for daytime normal working activities should be incorporated into the EM&A programme for implementation during construction. Details of the programme are provided in the stand-alone EM&A Manual.

Operation Noise

3.10.2 Road traffic noise levels should be monitored at representative NSRs, which are in the vicinity of the recommended direct mitigation measures, during the first year after road opening. Details of the programme are provided in the stand-alone EM&A Manual.

3.11 Summary

Construction Noise

3.11.1 This assessment has predicted the construction noise impacts of the Project during normal daytime working hours. With the use of quiet PME and movable barriers, and scheduling of construction activities, the noise levels at all representative NSRs would comply with the construction noise standard except educational NSR CMA, LWF, LCK, LCKP and CSBS during examination period.

3.11.2 The Contractor of the Project is suggested to liaison with these schools to check out their examination periods and activities in the beginning of the work programme. Thus, the Contractor can make good planning and arrangement of works and provide sufficient mitigation plans to avoid noisy construction activities undertaking during examination period.

Operation Noise

3.11.3 The potential road traffic noise impacts have been assessed based on the worst case traffic flows in 2025. The noise levels at some NSRs are predicted to exceed the EIA-TM traffic noise criteria due to both ‘New’ road and existing roads. As a result, direct mitigation measures have been proposed to mitigate the noise impacts at the NSRs where ‘New’ road noise contributions to the overall noise levels would be more than 1.0 dB(A).

3.11.4 With the proposed noise mitigation measures in place, the ‘New’ road noise contributions to the overall noise levels at all representative NSRs, except those mentioned in the following paragraphs, would be less than 1.0 dB(A) and the ‘New’ road noise levels would all be below the relevant noise criteria, though the overall noise levels at some of the NSRs would still exceed the relevant noise criteria. However, it should be noted that such noise exceedances at the representative NSRs are due to the existing roads.

3.11.5 Due to site constraint, noise enclosures could not be built to further alleviate the noise impacts at NSR TFH, CLFY2, CLFY3, CLFY5, CLFY6, HKG, TTP, JCP, HG, KFG1A and KFG1B. Eligibility test is conducted to assess the eligibility of these NSRs for provision of noise insulation works (NIW). The test results show that the NSRs are not eligible for provision of NIW.

3.11.6 Monitoring of road traffic noise is recommended to verify the effectiveness of the mitigation scheme during the first year after road opening.