This Section
presents the potential noise impacts associated with the Proposed Beach
Development at Lung Mei during the construction and operational phases.
5.2.1 Construction Phase
The principal
legislation relating to the control of construction noise is the Noise Control Ordinance (Cap 400) (NCO).
A number of technical memoranda (TMs) have been issued under the NCO to stipulate control approaches and
criteria and those which may be relevant to the construction works of the
Proposed Beach Development include the following:
·
Technical
Memorandum on Noise from Percussive Piling (PP-TM); and
·
Technical
Memorandum on Noise from Construction Work other than Percussive Piling (GW-TM).
Apart from
the above, the Environmental Impact
Assessment Ordinance (Cap 499) (EIAO)
also provides means to assess construction noise impacts. The Technical
Memorandum on Environmental Impact Assessment Process (EIAO-TM), issued under the EIAO,
provides guidelines and daytime noise criteria for evaluating construction
noise impacts.
Percussive Piling
Under the PP-TM, percussive piling is prohibited
at any time on Sundays and general holidays and during the weekday evening and
night-time hours (1900-0700 hours, Monday through Saturday). A Construction Noise Permit (CNP) is required
for such works during weekday daytime hours (0700-1900 hours, Monday through
Saturday).
General Construction Works
Under the EIAO, noise impact arising from general
construction works during normal working hours (ie 0700 to 1900 hours on any
day not being a Sunday or general holiday) at the openable windows of buildings
is to be assessed in accordance with the noise criteria as given in the EIAO-TM.
The EIAO-TM noise standards
are presented in Table 5.1.
Table 5.1: EIAO-TM
Daytime Construction Noise Standard
|
Use |
Noise Standard, Leq, 30 min dB(A) |
|
Domestic Premises |
75 |
|
Educational Institutions (normal periods)
Educational Institutions (during examination periods) |
70
65 |
When assessing a CNP
application for the use of Powered Mechanical Equipment (PME) during restricted
hours, the Noise Control Authority will compare the Acceptable Noise Levels
(ANLs), as promulgated in GW-TM, and
the corrected noise levels (CNLs) (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 have been
established to reflect the background characteristics of different areas. The relevant ANLs are shown in Table 5.2.
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 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 in granting a CNP. Nothing in this EIA Report shall bind the
Noise Control Authority in making his 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.
Table
5.2:
Acceptable
Noise Levels (ANL, Leq, 5 min dB(A))
|
Time period |
Area Sensitivity Rating |
||
|
A |
B |
C |
|
|
All
days during the evening (1900-2300 hours) and general holidays (including
Sundays) during the day and evening (0700-2300 hours) |
60 |
65 |
70 |
|
All
days during the night-time (2300-0700 hours) |
45 |
50 |
55 |
5.2.2 Operational
Phase
Fixed plant
noise is controlled under Section 13
of the NCO and the predictions are
made in accordance with the Technical
Memorandum on Noise from Places other than Domestic Premises, Public Places or
Construction Sites (IND-TM). The criteria noise limits are set out in the EIAO-TM as follows:
·
The total fixed source noise level at the facade
of the nearest NSR is at least 5 dB(A) lower than the appropriate ANL (as
shown in Table 5.3) as specified in
the IND-TM; or
·
Where the prevailing noise level in the area is
5 dB(A) or more below the appropriate ANL, the total fixed source noise level
must not exceed this noise level. Future
check of prevailing noise levels will be made during baseline noise measurement
prior to operation of the Project.
The criteria noise limits
stipulated in the IND-TM are
dependent on the Area Sensitivity Rating (ASR) of the NSRs, as shown in Table 5.3.
Table 5.3: ANLs to be used as
Operational Noise Criteria
|
Time Period |
Leq, 30min dB(A)) |
||
|
A |
A |
A |
|
|
Daytime 0700-1900 |
60 |
65 |
70 |
|
Evening 1900-2300 |
60 |
65 |
70 |
|
Night-time 2300-0700 |
5 |
55 |
60 |
As the Project Site is
located in a rural area and no influencing factors affect the NSRs, an ASR “A”
has been assumed for the NSRs located in the vicinity. Baseline noise measurements were made to
determine the prevailing noise levels at Lung Mei and to establish the noise
limit for the assessment of the operational noise impact. Details of the noise measurements are
provided in Section 5.3.3.
The Area Sensitive Rating
assumed in this Report is for the purpose of an indicative assessment only,
given that there are currently no influencing factors assumed in the vicinity
of the NSRs. It should be noted that
fixed noise sources are controlled under Section
13 of the NCO. At the time of investigation, the Noise
Control Authority shall determine noise impact from concerned fixed noise
sources on the basis of prevailing legislation and practices being in force,
and taking account of contemporary conditions / situations of adjoining land
uses. Nothing in this Report shall bind
the Noise Control Authority in the context of law enforcement against all the
fixed noise sources being assessed.
5.3.1 Baseline
Condition
The Proposed Beach
Development is located at Lung Mei in Tai Po (Figure 5.1). Two villages, Lung Mei Tsuen and Lo Tsz Tin
Tsuen, are located to the north of the Project Site. The Plover Cove Reservoir and a number of
water activity centres are located at Tai Mei Tuk at a distance of about 360 m
to the east of the Proposed Beach Development.
The background noise environment is dominated
by the road traffic noise from
5.3.2 Noise
Sensitive Receivers
Village
houses at Lung Mei and Lo Tsz Tin have been identified as noise sensitive
receivers (NSRs) that may be affected by noise associated with the construction
and operation of the Proposed Beach Development (Figure 5.1). The
planned/committed noise sensitive developments and uses in the vicinity of the
site have also been identified in the vicinity of the Project Site and are
presented in
Figure 5.1. Photographs showing the identified NSRs are
presented in Appendix D1.
Assessment
points have been selected to represent the identified NSRs for carrying out the
noise assessment (Appendix D1). The village house at No. 103 Lung Mei has
been used to represent an NSR instead of No. 101 Lung Mei as the latter has
been converted to a restaurant and no longer considered as an NSR. However, assessment has also been conducted
at No. 101 Lung Mei considering its potential change to residential use in
future. The locations of the noise
assessment points are shown in
Figure 5.2
and presented in Table 5.4.
Table 5.4: Selected Noise
Assessment Points
|
NSR |
Location |
Type of Uses |
|
N1 |
Village house - No. 165A Lung Mei |
Residential (3-Storey) |
|
N2 |
Village house - No. 103 Lung Mei |
Residential (3-Storey) |
|
N2a |
House - No. 101
Lung Meu |
Residential converted to Commercial (3-storey) |
|
N3 |
Village house - No. 70 Lo Tsz Tin |
Residential (3-Storey) |
|
N4 |
Village house - No. 79 Lo Tsz Tin |
Residential (3-Storey) |
5.3.3 Baseline
Noise Measurement
To investigate the prevailing noise levels at the NSRs at
Lung Mei, noise measurements were conducted on 4 March 2007 at two locations,
as indicated in
Figure 5.3 and Appendix D1. The noise measurements were conducted using a
01 dB Solo Sound Level Meter (Type 1) which was calibrated using a B&K
Sound Level Calibrator Type 4231 with a calibration signal of 94.0 dB(A) at
1kHz. The measurement was logged at LAeq,
in fast time weighting. Calibration and
measurement procedures in the IND-TM were
followed.
The
measurement results are summarised in Table
5.5.
Table 5.5: Measured
Prevailing Free-field Noise Levels
|
Noise Measurement Location |
Noise
Measurement Period |
Lmin, 30min,
dB(A) |
Leq, 30min,
dB(A) |
Lmax, 30min,
dB(A) |
|
M1 |
12:16:00 - 12:46:00 |
39.0 |
59.7 |
79 |
|
12:46:00 - 13:16:00 |
39.1 |
59.5 |
75.4 |
|
|
13:16:00 - 13:46:00 |
40.1 |
58 |
72.5 |
|
|
Average Leq, 30min
= 59 dB(A) |
||||
|
M2 |
13:47:03 - 14:17:03 |
36.9 |
52.2 |
63.3 |
|
14:17:03 - 14:37:03 |
40.5 |
51.9 |
69.3 |
|
|
14:47:03 - 15:17:03 |
41.5 |
53.1 |
65.8 |
|
|
Average Leq, 30min
= 52 dB(A) |
||||
A correction factor of 3 dB(A) for façade effect is applied
to the free-field noise measurement results to represent the noise level at
building facades. With the inclusion of
facade correction, the measured prevailing noise levels are in the range of 55
– 62 dB(A), and therefore a lower level of 55 dB(A) LAeq, 30min is
adopted as the daytime noise limit for NSRs located at Lung Mei for the
operational noise assessment.
5.4.1 Construction
Phase
Potential
impacts to the NSRs during the construction phase of the Proposed Beach
Development are expected to arise mainly from PME operating at construction
work sites. The key construction
activities are as follows:
·
Site formation;
·
Localised widening of
·
Construction of bathing facilities;
·
Construction of two groynes; and
·
Construction of culverts to the east and west of
the Project Site.
To minimise
the construction noise impacts, press-in piling method has been proposed to be
used instead of percussive piling. In
the event of percussive piling being required as a result of geological
constraints at the Project Site, a CNP should be applied for the percussive
piling works in accordance with the PP-TM. As the issuance of a CNP by the Noise Control
Authority would depend on the information submitted in the CNP application by
the Contractor, and the calculations to be conducted therein according to the
PP-TM, the assessment of percussive piling noise has not been included in this
assessment.
The normal
working hours of the contractor will be between 0700 and 1900 hours from Monday
to Saturday (except public holidays).
Given the constraints of the Project Site and scale of the concurrent
construction activities, there will be a limited number of plant items
operating on site at any one time. The
construction noise assessment has been undertaken based on the construction
programme and the plant inventory presented in Appendices D2 and
D3 respectively. All the PMEs listed in the plant inventory
are checked by the CEDD to be available in the market. The validity of the inventory has also been
reviewed by CEDD and confirmed to be practical and feasible for completing the
works for the Proposed Beach Development within the scheduled timeframe.
5.4.2 Operational
Phase
Noise
associated with the operational phase of the Proposed Beach Development is
expected to arise mainly from the fixed plant at the bathing facilities. The dominant noise sources are expected to
include the following equipment:
·
water and fire service pumps;
·
mechanical ventilation for plant rooms; and
·
public address (PA) systems.
The Proposed
Beach Development will not have night-time operation and the operation hours of
the PA systems will follow those of the Proposed Beach Development as indicated
in Table 5.6.
Table 5.6: Operation Hours of
the Proposed Beach Development
|
Period |
Time |
Remark |
|
April, May, September and October |
9:00 am - 6:00
pm |
Daily |
|
From June to August |
9:00 am - 6:00
pm |
Weekdays |
|
8:00 am - 7:00
pm |
Saturdays,
Sundays & Public Holidays |
|
|
From November to March |
8:00 am - 5:00
pm |
Daily |
As the
detailed design of the fixed plant equipment associated with the operation of
the Proposed Beach Development is not yet available at this stage, assumptions
on the sound power levels (SWLs) of the equipment have been made for the
operational noise assessment. These
assumptions are presented in Table 5.7. The operational plant inventory is presented
in Appendix D6. The maximum allowable SWLs presented in Table 5.7 should be included in the
tender specification to ensure the assumptions for the operational noise impact
assessment remain valid. The suppliers
of equipment should guarantee the specified SWLs, with the characteristics of
tonality, impulsiveness and intermittency accounted for, by providing
certificate of measurement and verify the SWL during testing and commissioning
in accordance with international standard procedures. If necessary, the suppliers should apply
attenuation measures (eg use of silencers) to achieve the guaranteed noise
levels during the detailed design stage.
Table 5.7: Assumption on the
Sound Power Levels of the Operational Equipment
|
Operational Equipment |
Maximum Allowable Sound Power Level, dB(A) |
|
Pumps |
92 |
|
Mechanical Fan |
88 |
|
PA system |
100 dB(A) for the loudspeaker cluster located at car park and
lifeguard lookout 98 dB(A) for the loudspeaker cluster located at building
facilities |
5.5.1 Construction
Phase
The
methodology for the noise impact assessment follows the procedures outlined in
the GW-TM, and is summarised as
follows:
·
Identify of a list of construction plant likely
to be required for each construction activity;
·
Assign sound power levels (SWLs) to the PME
proposed based on the GW-TM. When the PME is not listed in the TMs, reference is
made to SWLs provided in the document prepared by the Noise Control Authority
(http://www.epd.gov.hk/epd/english/application_for_licences/guidance/files/OtherSWLe.pdf)
and British Standard 5228, Noise and
Vibration Control on Construction and Open Sites - Part 1 (BS5228: Part 1:
1997) ([1]);
·
Calculate the SWLs for each construction
activity. With the construction works
which will not be carried out simultaneously according to the construction
sequences, maximum SWL of each activity is selected to predict the maximum
construction noise levels at the NSRs;
·
Calculate the correction factor, using a
conservative approach, based on the horizontal distance between the NSRs and
the notional noise source position of the work sites. The notional source
position of the work site was established in accordance with the procedures
stated in the GW-TM;
·
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.
Noise impacts
at NSRs were subsequently evaluated by comparing the predicted noise levels
with the EIAO-TM daytime construction
noise limits (Leq, 30min dB(A)), as outlined in Section 5.2.1.
In reality, some of the
PME will not be operating continuously within a work site. Utilisation rates for the PME that have been
adopted for the calculation of the SWL are summarised in Table 5.8. The utilisation
rates has also been reviewed by CEDD and confirmed to
be practical and feasible to achieve the construction programme.
Table 5.8: Utilisation
Rates for PME
|
PME |
Utilisation Rate |
|
Vibratory roller, timber sawing machine, bar ender and cutter, electrical drill, vibratory compactor |
50% |
|
Mobile crane,
excavator, vibratory poker, concrete lorry mixer, silent piler, road roller,
lorry, pneumatic breaker, backhoe, derrick lighter |
80% |
|
Diesel generator, grab
dredger, water pump, air compressor, pelican barge |
100% |
5.5.2 Operational
Phase
The
methodology for the noise impact assessment follows the procedures outlined in
the IND-TM. The methodology for the fixed plant noise
assessment is summarised as follows:
·
Identify types of equipment and the number of
equipment;
·
Calculate the maximum SWL for each type of
equipment;
·
Identify representative NSRs that may be
affected by the fixed plant;
·
Calculate the correction factor, using a
conservative approach, based on the horizontal distance between the NSRs and
the fixed plant sources; and
·
Present the results in terms of Leq, 30min
dB(A), as specified in the TM.
Under normal
circumstances, it is envisaged that the PA system will not be operated
continuously. As advised by Leisure and
Cultural Services Department (LCSD), the typical operating time for the PA
system is 2 minutes in every 15 minutes, and therefore it is assumed that the
operating time of the PA system will be 4 minutes in every 30 minutes and an
appropriate correction is included to account for this mode of operation. The assessment has also taken into account
the barrier correction and facade correction of +3 dB(A). The predicted noise levels at the NSRs are
compared with the criteria set out in Section
5.3.3. Mitigation measures have been
recommended in cases where an exceedance is predicted.
5.6.1 Construction
Phase
Owing to the
proximity of the NSRs to the Project Site, the NSRs would be adversely affected
by the construction activities. The
unmitigated construction noise levels at the representative NSRs have been
predicted and are summarised in Table 5.9. Details of the calculations are presented in
Appendix D4.
Table 5.9: Predicted
Construction Noise Levels (Unmitigated)
|
NSR |
Location |
Predicted
Construction Noise Levels, dB(A) |
|
N1 |
Village house - No. 165A Lung Mei |
66 – 79 |
|
N2 |
Village house - No. 103 Lung Mei |
68 – 76 |
|
N2a |
House -
No. 101 Lung Mei |
69 – 77 |
|
N3 |
Village
house - No. 70 Lo Tsz Tin |
71 – 78 |
|
N4 |
Village
house - No. 79 Lo Tsz Tin |
67 – 80 |
Note:
(a) The construction noise criterion is 75 dB(A).
To mitigate
the construction noise impact, practicable mitigation measures, including the
use of quiet construction plant and movable noise barriers, are recommended to
be implemented when works are undertaken close to the NSRs. In addition, site hoardings at the particular
work site boundary may be provided for achieving screening effect, provided
that the hoardings have no openings or gaps and meet the same specifications
for movable noise barriers. The proposed
movable noise barriers should be at least 3m high with a surface density of not
less than 7 kg m-2, which could provide a minimum of 5 dB(A)
attenuation. Skid footing of movable noise
barriers should be located at a distance not more than a few metres of
stationary plant and mobile plant such that the NSRs would not have direct line
of sight to the plant. The length of the
barriers should also be at least five times greater than its height. The locations of the proposed movable noise
barriers during construction phase are presented in Figure 5.4. The contractor will ensure that the hoardings and movable
noise barrier are properly maintained throughout the construction period. Details of the recommended mitigation
measures are presented in Tables 5.12 and
5.13.
The mitigated
construction noise levels at the representative NSRs are summarised in Table 5.10. Details
of the calculations are presented in Appendix D5. The mitigated construction noise levels are
below the daytime construction noise criterion of 75 dB(A) throughout the
construction period.
Table 5.10: Predicted
Construction Noise Levels (Mitigated)
|
NSR |
Location |
Predicted Construction
Noise Levels, dB(A) |
|
N1 |
Village house - No. 165A Lung Mei |
62 – 72 |
|
N2 |
Village house - No. 103 Lung Mei |
64 – 70 |
|
N2a |
House - No. 101
Lung Mei |
65 – 70 |
|
N3 |
Village house - No. 70 Lo Tsz Tin |
66 – 71 |
|
N4 |
Village house - No. 79 Lo Tsz Tin |
63 – 72 |
Notes:
(a) Mitigated with quiet construction plant and
noise barriers.
(b) Construction noise criterion is 75 dB(A).
The normal
working hours of the contractor will be between 0700 and 1900 hours from Monday
to Saturday (except public holidays).
Should evening and night work between 1900 and 0700 hours or work on
public holidays (including Sunday) be required, the contractor should submit a
CNP application for consideration by the Noise Control Authority. Conditions stipulated in CNPs should be
strictly followed.
5.6.2 Operational
Phase
The predicted
operational noise levels at the NSRs are summarised in Table 5.11. Details of calculation are presented in Appendix D6. With the maximum specified SWLs for the fixed
plant, the predicted operational noise levels at the representative NSRs comply
with the daytime noise criteria as discussed in Section 5.3.3.
Table 5.11: Predicted
Operational Noise Levels
|
NSR |
Location |
Predicted
Operational Noise Levels, dB(A) |
Operational
Noise Criterion, dB(A) |
|
N1 |
Village house - No. 165A
Lung Mei |
52 |
55 |
|
N2 |
Village house - No. 103
Lung Mei |
53 |
55 |
|
N2a |
House
-
No. 101 Lung Mei |
54 |
55 |
|
N3 |
Village
house - No. 70 Lo Tsz Tin |
52 |
55 |
|
N4 |
Village
house - No. 79 Lo Tsz Tin |
49 |
55 |
It should be
noted that the operational noise assessment presented above is based on a
worst-case scenario in which the equipment are assumed to be operated simultaneously,
which is unlikely to occur in real situation.
5.7.1 Construction
Phase
The
contractor is required to adopt the recommended mitigation measures as
specified in Tables 5.12 and 5.13 to mitigate the construction noise
impact at different construction stages.
Table 5.12: Use of Quiet PME
|
Quiet PME |
Reference |
SWL, dB(A) |
|
Mobile Crane |
SWL listed in the data
base of quality powered mechanical equipment prepared by the Noise Control
Authority |
107 |
|
Tracked Loader |
British Standard 5228 – Table C3, Reference No. 16 |
104 |
|
Pneumatic breaker |
British Standard 5228 – Table C2, Reference No. 10 |
110 |
|
Concrete Lorry Mixer |
British Standard 5228 – Table C6,
Reference No. 23 |
100 |
|
Excavator |
British Standard 5228 – Table C3,
Reference No. 97 |
105 |
Table 5.13: Summary of
Recommended Use of Noise Barrier
|
ID |
Task |
Work Activity |
Recommended Mitigation Measures |
|
1a |
Construction
Works on Land |
Site
Formation, construction of seawall, ramp, staircase, retaining walls, sump
tanks for grey water system and superstructure foundation |
·
Movable noise barrier should be provided for
excavator and mobile crane;
·
Timber sawing machine should be operated
behind site hoarding/ movable noise barrier; and
·
Concrete lorry mixer should be operated
behind site hoarding/movable noise barrier. |
|
1b |
Localised
road widening along |
·
Timber sawing machine should be operated
behind movable noise barrier; and
·
Movable noise barrier should be provided for
excavator and mobile crane. |
|
|
2 |
Car Park Paving |
·
Movable noise barrier should be provided for
excavator. |
|
|
3a |
Building Works |
Piling
works |
|
|
3b |
Foundation
and tanking |
·
Movable noise barrier should be provided for
excavator, mobile crane and earth auger; and
·
Timber sawing machine should be operated
behind site hoarding/ movable noise barrier. |
|
|
3c |
Superstructure |
·
Movable noise barrier should be provided for
mobile crane; and
·
Timber sawing machine should be operated
behind site hoarding/ movable noise barrier. |
|
|
3d |
Building
finishes & internal fitting-out |
·
Movable noise barrier should be provided for
mobile crane. |
|
|
4 |
Dredging for the Groynes |
- |
|
|
5 |
Rock filling for the Groynes |
·
Movable noise barrier should be provided for
excavator and derrick lighter. |
|
|
6a |
Box Culvert
Construction |
Construction
of gabion channel |
·
Movable noise barrier should be provided for
excavator. |
|
6b |
Construction
of western culvert |
·
Movable noise barrier should be provided for
excavator, mobile crane;
·
Concrete lorry mixer should be operated
behind site hoarding/movable noise barrier. |
|
|
6c |
Construction
of eastern culvert |
·
Concrete lorry mixer should be operated
behind site hoarding/movable noise barrier. |
|
|
6d |
Construction
of 90m box culvert |
·
Site hoarding should be provided for work site. |
|
|
7 |
Sand Filling |
·
Movable noise barrier should be provided for
excavator. |
|
|
Remark: (1) Movable
noise barriers and site hoarding should be at least 3m high with a surface
density of not less than 7 kg m-2. |
|||
In addition
to the recommended mitigation measures given in Table 5.12, 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
programme;
·
Silencers or mufflers on construction equipment
should be utilized and should be properly maintained during the construction
programme;
·
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.
With the
implementation of recommended mitigation measures, no residual impact at the
NSRs is anticipated.
5.7.2 Operational
Phase
Based on the
specified maximum SWLs for the fixed plant, the predicted operational noise
levels at the representative NSRs are expected to comply with the daytime
criteria. As discussed in Section 5.4.2, the suppliers of
equipment should apply attenuation measures (eg silencers), if necessary, to
achieve the guaranteed noise levels.
5.8.1 Construction
Phase
As mentioned
in Section 3.13, the construction
works of Tolo Harbour Sewerage of Unsewered Areas Stage I Phase
IIC (Agreement No. CE 18/94) (Phase IIC works) is anticipated to be from
November 2008 to November 2010, which coincides with
construction undertaken for the Proposed Bathing Beach Development,
but the details of the construction programme and associated plant inventory
are not available at this stage. Phase
IIC works is anticipated to involve mainly excavation and pipe laying works but
will be in a smaller scale as a result of limited space at
No cumulative impact is anticipated during the
operational phase.
5.9.1 Construction Phase
Noise
monitoring is recommended during the construction phase to ensure compliance
with the noise criterion at the NSRs.
Weekly noise monitoring should be undertaken at the representative NSRs
(N1 – N4). If house No. 101
Lung Mei (N2a)
is changed
to residential use, noise monitoring should be conducted at N2a instead of
N2. Regular
site audits at the frequency of twice a month should be conducted to ensure
that the recommended mitigation measures are properly implemented during the
construction stage.
5.9.2 Operational Phase
Results of
operational noise assessment indicate that the NSRs will not be affected by
fixed plant noise sources and therefore operational phase noise monitoring is
not required.
Owing to the
proximity of the NSRs to the Project Site, mitigation measures are required to
be implemented to mitigate the construction noise impacts. Practicable mitigation measures, including
use of quiet construction plant and movable noise barriers, have been recommended
to be implemented for different work stages.
With the implementation of mitigation measures, the mitigated
construction noise levels at the representative NSRs are anticipated to comply
with the construction noise criterion of 75 dB(A) throughout the construction
period. Noise monitoring during the
construction stage is recommended to ensure compliance with the relevant noise
criteria. The
potential cumulative noise impacts from the contemporary occurrence of the
Phase IIC works have been considered, and the assessment result indicates that
the cumulative construction noise level at the NSRs complies with the
construction noise criterion of 75 dB(A).
The predicted
operational noise levels at the representative NSRs are expected to comply with
the daytime criteria based on the assessment using a set of specified maximum
SWLs for the fixed plant to be installed at the Proposed Beach
Development. Attenuation measures, if
required, will be provided to the fixed plant for achieving the guaranteed noise
levels during the detailed design stage, and therefore operational phase noise
monitoring is not required.
