This Section
assesses the potential noise impacts associated with the construction,
operation, restoration and aftercare of the Extension.
The principal legislation relating to the
control of construction, restoration and aftercare noise is the Environmental Impact Assessment Ordinance (EIAO) (Cap. 499). The Technical Memorandum on Environmental Impact
Assessment Process (EIAO-TM),
issued under the EIAO, provides
guidelines and noise criteria for evaluating the noise impacts.
The Noise
Control Ordinance (Cap. 400) (NCO) also provides means to assess
construction, restoration and aftercare noise impacts. Various Technical Memoranda (TMs), which stipulate control approaches and criteria, have
been issued under the NCO.
The following TMs are applicable to the
control of noise impacts from construction activities:
·
Technical Memorandum on Noise from
Construction Work other than Percussive Piling (GW-TM); and
·
Technical Memorandum on Noise from
Construction Work in Designated Areas (DA-TM).
Under the EIAO, potential noise impact arising from general construction
works during normal working hours (ie 07:00 to 19:00
hrs on any day not being a Sunday or public holiday) at the openable
windows of buildings, which rely on opened windows for ventilation, is to be
assessed in accordance with the noise criteria specified in the EIAO-TM. The EIAO-TM
noise standards are presented in Table
5.2a.
Table 5.2a EIAO-TM
Day-time Construction Noise Standards (Leq,
30 min dB(A))
|
Use |
Noise Standard (dB(A)) |
|
Domestic Premises |
75 |
|
Educational Institutions (normal periods) Educational Institutions (during examination periods) |
70 65 |
|
Notes: (1) The above standards apply to uses which
reply on opened windows for ventilation. (2) The above standards shall be viewed as
the maximum permissible noise levels assessed at 1m from the external façade. |
|
When assessing a Construction Noise Permit
(CNP) application for the use of Powered Mechanical Equipment (PME) during the
restricted hours, the Noise Control Authority will compare the Acceptable Noise
Levels (ANLs), as promulgated in GW-TM, and
the Corrected Noise Levels (CNLs) (ie after accounting for factors such as barrier effects and
reflections) associated with the proposed PME operations. The ANLs are
related to the noise sensitivity of the area in question and different Area
Sensitivity Ratings (ASR) have been established to reflect the background
characteristics of different areas.
The appropriate ASR for the Noise Sensitive Receiver (NSR) is determined
with reference to Table 5.2b.
Table 5.2b Area
Sensitivity Ratings
|
Types of Area Containing NSR |
Degree to which NSR is affected by
Influencing Factor (IF) |
||
|
|
Not
Affected |
Indirectly
Affected |
Directly
Affected |
|
Rural area, including |
A |
B |
B |
|
Low density residential area consisting of low-rise or isolated
high-rise developments |
A |
B |
C |
|
Urban area |
B |
C |
C |
|
Area other than those
above |
B |
B |
C |
|
Notes: The following definitions apply: (a) " (b) "directly
affected" means that the NSR is at such a location that noise generated
by the IF is readily noticeable at the NSR and is a dominant feature of the
noise climate of the NSR; (c) "indirectly
affected" means that the NSR is at such a location that noise generated
by the IF, whilst noticeable at the NSR, is not a dominant feature of the
noise climate of the NSR; (d) "not
affected" means that the NSR is at such a location that noise generated
by the IF is not noticeable at the NSR; and (e) "urban
area" means an area of high density, diverse development including a
mixture of such elements as industrial activities, major trade or commercial
activities and residential premises. |
|||
The relevant ANLs
are shown in Table 5.2c.
Table 5.2c Acceptable Noise Levels for General Construction Works (ANL, Leq, 5 min dB(A))
|
Time period |
Area Sensitivity Rating (dB(A)) |
||
|
|
A |
B |
C |
|
All days during the evening (ie 19:00-23:00 hrs) and general holidays (including Sundays)
during the day and evening (ie 07:00-23:00 hrs) |
60 |
65 |
70 |
|
All days during the night-time (ie 23:00-07:00 hrs) |
45 |
50 |
55 |
The Noise Control Authority will consider
a well-justified CNP application, for construction works within restricted
hours as guided by the relevant Technical Memorandum issued under the NCO. The Noise Control Authority will take
into account adjoining land uses and any previous complaints against construction
activities at the site before making a decision. Nothing in this EIA Report shall
bind the Noise Control Authority in making its decision. The Noise Control Authority may include
any conditions in a CNP that it considers appropriate. Failure to comply with any such
conditions may lead to cancellation of the CNP and prosecution action under the
NCO.
The EIAO-TM
and Technical Memorandum on Noise From Places Other than Domestic Premises,
Public Places or Construction Sites (IND-TM) specifies the
applicable ANLs for the operation of the
Extension. The ANLs
are dependent on the ASR and the time of the day and are presented in Table
5.2d.
Table 5.2d ANLs to be used as Fixed Plant Noise Criteria
|
Time
Period |
Leq 30min
(dB(A)) |
||
|
|
ASR “A” |
ASR “B” |
ASR “C” |
|
Day-time (ie
07:00-19:00 hrs) |
60 |
65 |
70 |
|
Evening (ie
19:00-23:00 hrs) |
60 |
65 |
70 |
|
Night-time (ie
23:00-07:00 hrs) |
50 |
55 |
60 |
Fixed plant noise is
controlled under Section 13 of the NCO and the predictions will be
undertaken in accordance with the IND-TM. The noise criteria for planning and
design of Designated Projects are set out in the EIAO-TM as follows:
·
the noise level at the facade of the nearest NSR is at
least 5 dB(A) lower than the appropriate ANL (as shown in Table 5.2d) as
specified in the IND-TM; or,
·
the prevailing background noise level (for quiet areas
with a noise level 5 dB(A) below the appropriate ANL).
The noise criteria stipulated
in the IND-TM are also dependent on the ASR of the NSR, as shown in Table
5.2d. For this assessment, the ASR assumed for the NSR and
the associated ANL are discussed in Section
5.3.2.
The traffic noise standards for planning
purposes specified in Table 1 under Annex 5 of the EIAO-TM was employed as the noise limits for the road traffic noise
impact assessment. The applicable
road traffic noise standards are 70dB(A) L10, 1hr for domestic
premises and 65dB(A) L10, 1hr for education institutions and church,
respectively. These noise limits
were applied for the peak hour traffic flows and for uses that rely on opened
windows for ventilation.
The Extension Site is located near the
southern end of
In accordance with the requirements given
in Section 3.4.2.2 of the EIA Study Brief, the Study Area for the noise impact
assessment covered a distance of 300m from the roads with traffic generated by
the Extension. Only the first layer
of the NSRs located along
Existing NSRs
that would potentially affected by the Extension are identified as the Island
Resort at Siu Sai Wan which
is located at more than 2.4km to the south-west of the Extension Site boundary,
and Oscar By the Sea in Tseung Kwan O which is
located at more than 3.2km to the north of the Extension Site. Other existing NSRs,
including residential developments and schools, are located at a further
distance away to the north. Planned
residential developments and schools in TKO Area 85 and Area 86 are located at
more than 1.5km to the north of the Extension Site boundary. The locations of the identified
representative NSRs and photographs showing the
existing representative NSRs are presented in Figures 5.3b to 5.3e. The locations of the identified
representative planned NSRs for assessment are
presented in Figure 5.3f.
As the NSRs are located in an isolated high-rise development area
and are indirectly affected by
The representative
NSRs located
along
Table 5.3a Representative
Noise Sensitive Receivers Selected for Assessment
|
NSR |
Location |
Use |
No. of Floors |
Distance to the Extension Site (km)
(Approx.) |
Selected for Noise Impact Assessment |
||
|
|
Construction |
On-site Operational |
Road Traffic |
||||
|
NFP1 |
|
Residential |
39 – 43 |
4.0 |
|
|
ü |
|
LCN1 |
La Cite Noble |
Residential |
44 – 47 |
3.9 |
|
|
ü |
|
YUKMC1 |
|
Residential |
38 |
4.1 |
|
|
ü |
|
THWV1 |
Tin Ha Wan Village |
Residential |
3 |
4.0 |
|
|
ü |
|
MTE1 |
Ming Tak
Estate |
Residential |
38 |
4.0 |
|
|
ü |
|
OS1 |
Oscar By the Sea |
Residential |
32 - 49 |
3.2 |
|
|
ü |
|
IR1 |
Island Resort |
Residential |
50 - 51 |
2.4 |
ü |
ü |
|
|
A86R1(a) |
Planned Residential Development in Area
86 |
Residential |
40 – 50 |
1.5 |
ü |
ü |
ü |
|
A86R2(a, b) |
Planned Residential Development in Area
86 |
Residential |
40 – 50 |
1.7 |
|
|
ü |
|
Notes: (a)
Under construction (b)
Only applicable to road traffic noise assessment
with Cross Bay Link. |
|||||||
To investigate the prevailing noise levels
in the Extension Site, noise measurements were made from 23 to 24 August 2006 near the office of
Green Valley Landfill Limited at the existing SENT Landfill. The noise measurements were conducted
using a 01dB Sound Level Meter (Type 1), which had been calibrated using a SVAN
Sound Level Calibrator Type 4231 with a calibration signal of 94.0 dB(A) at
1kHz. The measurements were
conducted with reference to the calibration and
measurement procedures stated in the IND-TM.
As the background noise in the Extension
Site is generally low, especially during night-time, the prevailing noise
measurement represents the quietest acoustic environment in the vicinity of the
NSRs.
Since the microphone was set in the free field measurement mode, a
façade correction of 3dB(A) was applied to the noise measurement results. The measured prevailing background noise
levels including façade correction were in the range of 60 – 75 dB(A) Leq, 30min and 55 – 64 dB(A) Leq, 30min during 13:00 to 20:00 hrs
and 23:00 to 07:00 hrs, respectively.
The major activities associated with the
construction phase will involve the use of PME and they are summarised as
follows:
·
Foundation
and building structure construction for the infrastructure area – transportation of plant and equipment,
excavation, installation of formwork and reinforcement, concreting, and
construction of monitoring wells;
·
Demolition
of existing structures at the infrastructure area – concrete breaking and crushing;
·
Site
formation and installation of liner – site formation, installation of liner, provision
of leachate and landfill gas collection system,
construction of drainage channels and sumps, construction of drainage tunnel
and road construction;
·
Construction
activities associated with the construction/operation in the Extension - construction of drainage channels and
sumps, construction of drainage tunnel and road construction during each phase
of the Extension;
·
Capping
and Landscaping (progressive restoration) – the use of excavator,
bulldozer, dump truck, vibratory roller, loader and mobile crane; and
·
Construction
of permanent gas wells – the use of drilling rig, mobile crane and small
excavator.
The
construction noise assessment was undertaken based on the proposed construction works programme (see Figure
3.4a), phasing plans (see Figure 3.6a to 3.6k) and plant inventory presented in Annex B1. The plant inventory was reviewed by the
Design Engineer and was confirmed to be suitable for completing the Assignment
within the scheduled timeframe.
The normal working hours of the Contractor
will be between 07:00 and 19:00 hrs from Monday to Saturday (except public
holidays). Construction activities
during restricted hours are not expected.
Should evening and night works between 19:00 and 07:00 hrs or on public
holidays (including Sundays) be required, the Contractor will submit a CNP
application which will be assessed by the Noise Control Authority.
Landfilling Operation
The Extension will be operated from Year
2013 to Year 2018 and will involve deposition and compaction of waste,
placement of intermediate cover, removal of intermediate cover, capping and
landscaping. The Extension
will be operated in six phases starting from the south and filling
progressively to the north as shown in Annexes
B1 and B4. The major activities associated with the
operational phase will involve the use of PME and they are summarised as
follows:
·
Deposition
and compaction of waste –
transportation and deposition of waste, and compaction; and
·
Placement
and removal of daily and intermediate cover – with the use of
excavator, bulldozer, dump truck, vibratory roller and loader.
The landfill operates daily from 08:00 to
23:00 hrs. However, the placement
of daily cover will be undertaken for about 25 minutes after 23:00 hrs. The noise levels due to the use of PME
were predicted and compared with the day-time and night-time noise criteria as
per the EIAO-TM.
Fixed
Plant Operation
The Extension also involves the operation
of a new leachate treatment plant (LTP) and a
landfill gas treatment plant on-site.
The new LTP and landfill gas treatment plant will be constructed at the
new infrastructure area as shown in Figure 5.3g. The Design Engineer has confirmed that
the type and power of the new LTP will be of a scale similar to that of the Bioplant at the existing SENT Landfill and similar building
envelopes currently provided for the fixed equipment will also be provided for
the LTP and landfill gas treatment plant at the new infrastructure (Annex B4). Additional number of equipment will not
be required for the operation of the Extension.
Reference was made to the GW-TM for the sound power levels (SWLs) of the fixed plant items that were similar in nature
to certain PME in the aforementioned GW-TM. Comparing with the sound data provided
by the operator of the existing SENT Landfill for the equipment currently being
used (Annex B4), the noise assessment
based on the SWLs from the GW-TM would have represented the worst scenario as the sound data
for the equipment currently being used is far lower than that from the GW-TM. Similarly, reference was made to the EIA
Report for North East New Territories (NENT) Landfill Extension ([1]).
A survey was undertaken on 23 August 2006
to identify the major noise sources of the Bioplant
and landfill gas treatment plant. The
new LTP and landfill gas treatment plant will operate on a 24-hour basis.
Road
Traffic Noise
The Extension peak operating hour (ie the hour with the maximum number of trucks associated
with the operation of the Extension) is expected to be 14:00 to 15:00 hrs (SENT
Peak) and 17:15 to 18:15 hrs (PM Peak) based on the traffic survey conducted
for the operation of the existing SENT Landfill. There will not be any potential traffic
noise impact during the night-time period as the landfill will be closed after
23:00 hrs.
According to the Civil Engineering and
Development Department (CEDD), the Cross Bay Link (CBL) connecting Tiu Keng Leng and
To enable identification of the traffic
noise contribution from the operation of the Extension and the prevailing
situation, traffic noise impact assessment was undertaken for the scenarios
shown in Table 5.4b.
Table 5.4b Scenarios
of Traffic Noise Impact Assessment
|
Peak Hour Scenario |
Traffic Noise Impact Assessment
Scenario |
|
|
2006 AM
peak hour |
With
Existing SENT Landfill |
Without
Existing SENT Landfill |
|
2006 PM
peak hour |
With
Existing SENT Landfill |
Without
Existing SENT Landfill |
|
2006 SENT
peak hour |
With
Existing SENT Landfill |
Without
Existing SENT Landfill |
|
Without |
|
|
|
2018 AM
peak hour |
With the
Extension |
Without
the Extension |
|
2018 PM
peak hour |
With the Extension |
Without
the Extension |
|
2018 SENT
peak hour |
With the
Extension |
Without
the Extension |
|
With |
|
|
|
2018 AM
peak hour |
With the
Extension |
Without
the Extension |
|
2018 PM
peak hour |
With the
Extension |
Without the
Extension |
|
2018 SENT
peak hour |
With the
Extension |
Without
the Extension |
Traffic
forecasts for each of the scenarios shown in Table 5.4b were prepared by the Traffic Consultant for the worst
case representative assessments (Annex B2). The maximum estimated traffic flows
in/out of the existing SENT Landfill during AM, PM and SENT peak hours for the
“with existing SENT Landfill” scenarios for Year 2006 were 105/105, 110/110 and
110/110 vehicles, respectively([2]).
The maximum hourly traffic forecast for the “with the Extension”
scenarios in/out of the Extension during AM, PM and SENT peak hours for Year
2018 was 136/136, 143/143 and 143/143 vehicles (1),
respectively. The traffic flows in/out
of the Landfill Extension generated by the scenarios with and without CBL would
be the same.
The traffic forecast employed for this
assessment has been submitted to the Transport Department (TD) and it was
confirmed that TD had no comment on the data set.
From the Year 2018 when the Extension is
full, it will be restored. The
Contractor will be responsible for the aftercare of the restored Extension for
a period of 30 years. The aftercare
of the restored Extension will involve limited construction works and is
expected to have insignificant noise impact compared with the construction and
operation/restoration of the Extension.
The LTP and landfill gas treatment plant will continue to operate during
the aftercare period.
The restored Extension (and together with
the restored SENT Landfill) may be developed into various beneficial uses (eg as open space, education/ecological park, hiking track,
or passive recreational uses (which are referred to as the afteruses)
subject to future planning. It
should be noted that the afteruse of the restored
Extension did not form part of the Extension contract. The potential environmental impacts
associated with the development and operation of the afteruse(s)
will be subject to a separate EIA Study, where appropriate.
The construction noise impact assessment
was undertaken in accordance with the procedures outlined in the GW-TM, which is issued under the NCO and the EIAO-TM. The assessment
methodology is summarised as follows:
·
Locate
representative NSRs that may be affected by the
Extension;
·
Determine
the plant teams for corresponding activities, based on the agreed plant
inventory;
·
Assign
sound power levels (SWLs) to the PME proposed based
on the GW-TM, British Standard
BS 5228([3]) and list of SWLs
of other commonly used PME([4]);
·
Calculate
the correction factors based on the distance between the NSRs
and the notional noise source position of the work sites;
·
Apply
corrections in the calculations, such as potential screening effects and
acoustic reflection, if any; and
·
Predict
the construction noise levels at NSRs in the absence
of any mitigation measures.
The total SWL associated with each construction
activity was established based on an assumed plant inventory. The
notional source position was established in accordance with the procedures
stated in the GW-TM. The
potential noise impacts at NSRs were subsequently
evaluated by comparing the predicted noise levels with the EIAO-TM day-time construction noise limits (Leq,
30min dB(A)), as outlined in Section
5.2.1.
The potential sources of noise impacts
that may arise from the operation of the Extension include the use of PME for
waste placement, operation of the LTP and landfill gas treatment plant and the
noise impact due to the traffic generated by the Extension. The
assessment methodologies employed for the on-site operational noise impact
assessment are summarised below.
On-site
Operational Noise
Noise impact assessment due to the on-site
operation of the Extension was undertaken based on standard acoustic principles
as per the requirements of the EIAO-TM. The assessment took into account typical
SWLs for the plant items, including the EIA Report
for North East New Territories (NENT) Landfill Extension ([5]), distance attenuation, topography
attenuation and façade reflection.
Based on the site survey conducted on 23 August 2006, it was indicated that
except two small compressors placed outdoors, all noisy equipment was fully
enclosed within the concrete building structures of two blower rooms and a
landfill gas power plant room.
Noise was emitted to the external environment through lourves or openings for exhaust fans only. The Design
Engineer has confirmed that the type and power of the new LTP will be of a
scale similar to that of the existing SENT Landfill and similar building
envelopes currently provided for the fixed equipment will also be provided for
the LTP and landfill gas
treatment plant at the new infrastructure area.
The noise impact due to the waste filling
and the operation of the LTP and the landfill gas treatment plant was assessed
and compared with the noise criteria as outlined in Section 5.2.2.
Road
Traffic Noise
The noise impact assessment due the truck
movements at Wan Po Road and Chiu Shun Road during the peak hours, was based on
the procedures given in The Calculation
of Road Traffic Noise (CRTN)
prepared by the UK Department of
Transport. The assessment has
been undertaken for the scenarios of with and without the existing SENT
Landfill during AM, PM and SENT peak hours at the prevailing Year 2006 and with
and without the Extension during AM, PM and SENT peak hours at the worst
assessment Year 2018 (for both scenarios with and without Cross Bay Link). The traffic forecast provided by the
Traffic Consultant is given in Annex B2.
In accordance with the Environmental
Permit (EP-073/2000/D) issued by the EPD based on the Tseung
Kwan O Development Contract F - Grade Separated Interchange T1/P1/P2,
Environmental Impact Assessment (EIA) Study (Register No. AEIAR – 017/1999), an
absorptive 5.5m inverted L-shaped barrier of about 175m length along the
central divider and an absorptive 5.5m inverted L-shaped barrier of about 450m
length alongside the southbound verge of Wan Po Road (referred as Road P1 in
the above EP) near On Ning Garden and Nan Fung Plaza
have been constructed. The noise
barriers were taken into account in the traffic noise impact assessment.
Other existing noise mitigation measures,
including a cantilevered noise barrier near the junction of
With reference to the EIA Report for
Further Development of Tseung Kwan O – Feasibility
Study ([6]), a 120 m long cantilevered barrier (5.5 m
high vertical barrier with 3 m cantilever) located at the kerb of the eastbound
carriageway, three sections of 100 m, 200 m and 168m long cantilevered barriers
(5.5 m high vertical barriers with 5m, 4.5m and 5m cantilevers) located at the
central divider, have been proposed for CBL to protect the NSRs
at Area 86. The above-mentioned
noise barriers have been included in the traffic noise impact assessment for
the scenarios with CBL.
Information on low noise surfacing for the
roads within the Study Area has been reviewed. Low noise surfacing has been included in
the traffic noise impact assessment for the roads, including sections of
The predicted noise levels due to the
traffic generated on Wan Po Road and Chiu Shun Road were evaluated by comparing
with the EIAO-TM traffic noise limits
(L10, 1hr dB(A)), as outlined in Section
5.2.2.
As
the representative NSRs are located at more than
1.6km away from the Notional Source Position, the predicted noise levels at the
representative NSRs would comply with the stipulated
construction noise criteria. A
summary of the predicted construction noise levels is presented in Table
5.6a. Details of the noise
calculations are presented in Annex B3.
Table 5.6a Predicted
Construction Noise Levels at Representative NSRs
|
NSR |
Description |
Approx. Horizontal Distance to Notional
Source Position(a) (km) |
Predicted Construction Noise Levels(b), Leq, 30 min dB(A) |
|
A86R1 |
Planned
Residential Development in Area 86 |
1.6 |
41 - 59 |
|
IR1 |
Island
Resort |
2.6 |
37 - 55 |
|
Notes: (a) According
to the GW-TM, notional source position refers to the position mid-way between
the approximate geographical centre of the construction site and its boundary
nearest to the NSR. (b) All
predicted noise levels were corrected with 3dB(A) for façade reflection. (c) Assessment
criterion for construction noise impact is 75 dB(A) for domestic premises. |
|||
The
predicted construction noise levels at the representative NSRs
are well below the noise criteria, the NSRs will not be
adversely affected by the construction of the Extension.
The noise levels
due to the operation of the landfilling works, new
LTP and the landfill gas
treatment plant at the representative NSRs were predicted and are summarised in Table 5.6b. The predicted noise levels are well
within both the stipulated day-time and night-time (ANL-5) noise criteria. Details of the noise calculations are
presented in Annex B5.
Table 5.6b Predicted
Operational Noise Levels at Representative NSRs
|
NSR |
Description |
Predicted Facade Noise Level(a), Leq, 30 min dB(A) |
|
|
Day-time
(07:00 – 23:00hrs) |
Night-time
(23:00 – 07:00hrs) |
||
|
A86R1 |
Planned Residential Development in Area
86 |
41 – 53 |
33 - 47 |
|
IR1 |
Island Resort |
44 - 50 |
43 - 46 |
|
Notes: (a) All
predicted noise levels were corrected with 3dB(A) for façade reflection.. (b) According
to EIAO-TM, day-time and night-time (ANL-5) noise criteria are 60 dB(A) and 50 dB(A),
respectively. |
|||
As NSR A86R1 will be screened from the LTP
and landfill gas treatment plant by the buildings in Tseung
Kwan O Industrial Estate and the existing topography near the SENT Landfill, a 10dB(A)
attenuation was included in the assessment.
The noise
assessment for landfilling and fixed plant operation
did not account for the atmospheric absorption and the realistic utilisation
rates of the PME (ie not operating for 100% of the
time). Screening by building envelopes and attenuation by
acoustic treatment for the fixed plant items were not included in the
assessment. The Design
Engineer has confirmed that building envelopes and acoustic treatment similar
to the existing SENT Landfill will be provided for the new equipment. Therefore, the noise levels at the NSRs in real situation will be less than the predicted
noise levels presented in Table 5.6b.
The predicted façade noise
levels at the representative NSRs for the Years 2006
and 2018 (with and without CBL in operation) are presented in Annex B6. The noise levels are predicted for the purpose of
assessing the road traffic noise impact due to the Extension, and therefore,
the predicted noise levels are for indicative uses only. Detailed road traffic noise impact
assessments should be referred to corresponding EIA Reports or Planning
Submissions for individual developments. Results indicate that the predicted façade
noise levels complied the stipulated noise limit of 70dB(A) for domestic premises at all NSR locations, except
A86R1. This exceedance
would mainly be due to the background traffic at
The noise contributions due
to the traffic generated by the Extension were predicted to be less than
0.4dB(A). In view of the fact that
the noise contributions due to the Extension are less than 1.0dB(A) for Year
2018 with and without CBL in operation, the traffic noise impact is considered
insignificant. Detailed results of
the road traffic noise impact assessment are given in Annex B6. The computer
road plots and input files of the model are provided in Annexes B7 and B8,
respectively.
While adverse noise impact is not expected
during the construction/restoration phase of the Extension, good site practices
should be implemented by the Contractor to minimise the construction noise
impact. The site practices listed
below should be adopted during the construction phase:
·
Only
well-maintained plant should be operated on-site and plant should be serviced
regularly during the construction program;
·
Silencers
or mufflers on construction equipment should be utilized and should be properly
maintained during the construction program;
·
Mobile
plant, if any, should be sited as far from NSRs as
possible;
·
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, wherever possible, be
orientated so that the noise is directed away from the nearby NSRs; and
·
Material
stockpiles and other structures should be effectively utilised, wherever
practicable, in screening noise from on-site construction activities.
While no adverse noise impact is expected during
the operational phase of the Extension, it is still recommended that the
following measures be implemented as far as practicable:
·
Choose
quieter PME;
·
Include
noise levels specification when ordering new plant items;
·
Locate
fixed plant items or noise emission points away from the NSRs
as far as practicable;
·
Locate
noisy machines in completely enclosed plant rooms or buildings; and
·
Develop
and implement a regularly scheduled plant maintenance programme so that plant
items are properly operated and serviced.
The programme should be implemented by properly trained personnel.
Notwithstanding the prediction that the NSRs will not be subject to adverse noise impact during the
construction and operational phases, noise monitoring is recommended to be
carried out during the construction, operational and restoration stages of the
Extension to ensure noise compliance.
In addition, site audits are recommended to be undertaken regularly
during the construction, operation/restoration and
aftercare phases to ensure that appropriate environmental protection and
pollution control mitigation measures are properly implemented. Details of the EM&A requirements are
provided in Section 11 and the EM&A Manual.
No adverse noise impacts are anticipated at the representative NSRs during the construction, operational, restoration and
aftercare phases due to the Extension because of the large horizontal separation. To further minimise the noise impacts,
good site practices and noise reduction measures are recommended during the
construction and operational/restoration phases of the Extension.
