7.1
This Section presents an
assessment of the potential noise impacts associated with the construction and
operation of the Project and the demolition of the existing crematorium. The noise
impact assessment was conducted in accordance with the requirements of Annex 5
and Annex 13 of the Technical Memorandum on Environmental Impact Assessment
Process (EIAO-TM) as well as the requirements set out under Clause 3.4.5 and
Appendix C of the EIA Study Brief.
Environmental
Legislation, Policies, Plans, Standards and Criteria
7.2
Noise impacts were assessed in
accordance with the criteria and methodology given in the Technical
7.3
The NCO provides the statutory
framework for noise control. This defines statutory limits applicable to
equipment used during the construction and operation phases of the Project. The
NCO invokes four Technical
·
Technical
·
Technical
·
Technical
·
Technical
7.4
The NCO and the accompanying
Technical
7.5
With
regard to the assessments of the construction noise impact during restricted
hours and operation noise impact, the NCO designates acceptable noise levels
for Noise Sensitive Receivers (NSRs) on the basis of an Area Sensitivity Rating
(ASR), based on the characteristics of the area within which they are located
such as rural, village, low-density residential, or urban (see Table 7.1). Within these areas, the
presence of "influencing factors" (such as the presence of industrial
activities or major roads) can further affect the ASR and hence the acceptable
noise level.
Table 7.1 Area Sensitivity Ratings (ASRs)
|
Type of Area
Containing NSR |
Degree to
which NSR is affected by Influencing Factor |
||
|
Not Affected |
Indirectly Affected |
Directly
Affected |
|
|
Rural Area |
A |
B |
B |
|
Urban Area |
B |
C |
C |
|
Low density
residential area consisting of low-rise or isolated high-rise developments |
A |
B |
C |
|
Area other
than those above |
B |
B |
C |
Construction
Noise
7.6
Under
the GW-TM, noise from construction activity is not restricted between 0700 and
1900 hours on weekdays, except Public Holidays. However, the EIAO-TM identifies
a daytime general construction noise limit of 75 dB(A) for domestic premises
and 70 dB(A) for educational institutions during normal teaching periods (65
dB(A) during examination periods). These
noise standards were used as the assessment criteria in the construction noise
assessment for non-restricted hours.
7.7
The
NCO provides the statutory framework for noise control of construction work,
other than percussive piling, using powered mechanical equipment (PME) between
1900 and 0700 hours or at any time on Sundays and general holiday (that is,
restricted hours).
7.8
Between
1900 and 0700 hours and all day on Sundays and public holidays, activities
involving the use of PME for the purpose of carrying out construction work is
prohibited unless a construction noise permit (CNP) has been obtained. A CNP may be granted provided that the
Acceptable Noise Level (ANL) for the NSRs can be complied with. ANLs are assigned depending upon the area
sensitive rating (ASR). The
corresponding ANLs for evening and night-time periods are given in Table 7.2.
Table 7.2 Acceptable Noise Levels for Construction Work (Restricted Hours)
|
Time Period |
Acceptable Noise Level (ANL) |
||
|
ASR A |
ASR B |
ASR C |
|
|
All days during the evening (1900 to 2300 hours), and general holidays
(including Sundays) during the daytime and evening (0700 to 2300 hours) |
60 |
65 |
70 |
|
Night (2300 to 0700 hours) |
45 |
50 |
55 |
7.9
The Area Sensitivity Ratings assumed in this EIA
Report are for indicative assessment only. Despite any description or
assessment made in this EIA Report on construction noise aspects, there is no
guarantee that a Construction Noise Permit (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 making his decision in
granting a CNP. Nothing in this EIA Report shall bind the Noise Control
Authority in making his decision. If a CNP is to be issued, the Noise Control
Authority shall include in it any Condition he thinks fit. Failure to comply
with any such conditions will lead to cancellation of the CNP and prosecution
action under the NCO.
Operation
Noise
7.10
Fixed
noise sources associated with the Project would be controlled by the NCO and
IND-TM. The Acceptable Noise Levels (ANL) is a function of the type of area
within which the NSRs are located, and the degree of the effect on the NSRs of
influencing factors such as major roads and industrial areas. According to the
IND-TM, the ANLs for different Area Sensitivity Ratings (ASRs) are given in Table 7.3.
Table 7.3 Acceptable Noise Levels for Fixed Noise Sources
|
Time Period |
Acceptable
Noise Level (ANL) |
||
|
ASR A |
ASR
B |
ASR
C |
|
|
Daytime and Evening (0700 to 2300 hours) |
60 |
65 |
70 |
|
Night (2300
to 0700 hours) |
50 |
55 |
60 |
7.11 In any event, the Area Sensitivity Rating assumed in the EIA Report is for indicative assessment only. It should be noted that the 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 the EIA Report shall bind the Noise Control Authority in the context of law enforcement against all the fixed noise sources being assessed.
7.12 While the noise impact arising from newly proposed fixed plant would be assessed against the planning criterion stipulated in EIAO-TM, the cumulative noise impact arising from existing fixed plant and newly fixed plant during testing & commissioning (T&C) stage of Phase 1 would be assessed against ANL under NCO. This approach was adopted in an EIA Study for Harbour Area Treatment Scheme (HATS) Stage 2A which was approved by EPD under EIAO in October 2008.
Noise Criteria for Newly Proposed Equipment
7.13 The NSRs are located in the area other than rural area, low density residential area and urban area, and they are not affected by influencing factors (i.e. industrial activities or major roads). With reference to Table 7.1 above, ASR of “B” has been assumed for the NSRs in the vicinity of the proposed Project site. The EIAO-TM recommends that the level of the intruding noise at the façade of the nearest sensitive use should be at least 5 dB(A) below the appropriate ANL or, in the case of background noise being 5 dB(A) lower than the ANL, the predicted noise level arising from the operation of the proposed Project at the façade of the nearest sensitive use should not exceed the background noise level. In this regard, noise measurement was undertaken in the vicinity of the representative NSRs to study the prevailing noise level (see Appendix 7.1). The assessment criteria for newly proposed fixed noise sources, as adopted in this EIA Study, are presented in Appendix 7.2.
Noise Criteria for Cumulative Noise Impact
7.14 Cumulative noise impacts arising from existing equipment and new equipment during T&C stage of Phase 1 would be calculated and compared against relevant ANL criteria (i.e. 65 dB(A) for daytime/evening and 55 dB(A) for night-time) as shown in Table 7.3.
Description of the Environment
Existing Noise Environment
7.15
The
project site is the site of the existing Cape Collinson Crematorium at
Noise Sensitive Receivers
7.16
In
accordance with Appendix C of the Study Brief, the study area for noise impact
assessment is 300 metres from the boundary of the Project.
7.17
To
evaluate the construction and operational noise impacts likely to arise from
the Project, representative NSRs (both existing and planned NSRs) were selected
within the study area according to the criteria set out in the EIAO-TM, through
site visits and a review of relevant land use plans including the Outline
Zoning Plan (OZP).
7.18
A
relevant OZP No. S/H20/17, which was gazetted on
7.19
According
to Annex 13 of the EIAO-TM,
7.20
Figure
7.1 shows the
site, study area and the geographical locations of the representative NSRs. Details of the representative NSRs are shown in Table 7.4. Photographs of the representative NSRs are shown in Appendix 7.3. These identified noise assessment
points have been agreed with Environmental Protection Department prior to the
quantitative assessment (see Appendix 7.3).
Table 7.4 Details of Representative Noise Sensitive Receivers
|
NSR
ID |
Description |
No.
of Storey |
Uses |
Distance between NSR and
nearest Project Boundary (m) |
|
KTC |
|
34 |
Residential |
120 |
|
SQ1 |
Staff Quarters of |
2 |
Staff Quarters |
90 |
|
SQ2 |
Staff Quarters of Tai Tam
Gap Correctional Institution |
4 |
Staff Quarters |
135 |
|
SQ3 |
Staff Quarters of |
3 |
Staff Quarters |
235 |
Identification of Environmental Impacts
Potential Noise Impacts
7.21 Major potential noise impacts arising from the Project would be:
·
Demolition/Construction noise
·
Operation noise
Demolition/Construction
Noise
7.22
The
potential source of noise impact during the demolition/construction phase of
the Project would be the use of PME for various demolition/construction
activities. The
construction noise impacts arising from the proposed Project are discussed in
Section 7.43.
7.23 As shown in Figure 2.7, construction work of Phase 1 would commence in July 2010 for completion in March 2012, while the demolition work of existing crematorium and construction work of Phase 2 would commence in March 2012 for completion in December 2014. Prior to Phase 1 construction works, tree transplanting will be carried out in advance from January 2010 to June 2010. No overlapping of construction/demolition works between Phase 1 and Phase 2 will occur. The Project would involve the following major construction activities. As confirmed with the Project Proponent, percussive piling and blasting work would not be required, and the works would be carried out by general construction methods.
·
Site formation
·
Demolition work
·
Substructure work
·
Superstructure work
·
Landscape work
·
Fitting-out work (for external glass wall/skylight)
7.24 Generally, the construction activities of the Project would be carried out in non-restricted hours (0700-1900 hours) during normal working days. In case of any construction activities during restricted hours, it is the Contractor’s responsibility to ensure compliance with the NCO and the relevant TMs. The Contractor will be required to submit CNP application to the Noise Control Authority and abide by any conditions stated in the CNP, should one be issued.
7.25 Based on currently available information, no concurrent projects have been identified within 300m of the project boundary. Thus, the cumulative construction noise impact due to the demolition/construction works of the Project and other likely concurrent projects was not assessed in this EIA Study.
Operation
Noise
7.26 According to information provided by the Project Proponent, the fixed plant to be installed for the crematorium includes condensers of split-type air-conditioning units, radiators for cremators, fan rooms and general exhaust fans for plant rooms. The operation noise impacts arising from the proposed Project are discussed in Sections 7.44 to 7.48.
7.27 Fixed plant will also be present inside the cremator plant rooms. As confirmed with the Project Proponent, the major noise generating fixed plant inside the cremator plant rooms include crematory furnace, cooling water pump and air compressor. The fixed plant installed inside the cremator plant rooms will be similar to those equipped in the new Diamond Hill Crematorium. With reference to the approved EIA Report for Provision of Cremators at Wo Hop Shek Crematorium, the measured noise level of fixed plant inside cremator plant room at new Diamond Hill Crematorium was 83.6 dB(A). Since the fixed plant inside the cremator plant rooms are fully enclosed inside concrete structures, a minimum of 20 dB(A) of screening correction is expected from the concrete structures. With the nearest NSR locating about 105m away from the new crematorium, noise level would be further reduced about 48 dB(A) due to distance attenuation. Thus, the noise contribution due to fixed plant inside the cremator plant rooms at the nearest NSR will not be more than 20 dB(A). As such, the noise impact from the fixed plant inside the cremator plant rooms at the representative NSRs is anticipated to be insignificant.
7.28 During testing and commissioning of new cremators under Phase 1, the existing crematorium would be still operative for the public use. As advised by the Project Proponent, however, the new cremators under Phase 1 would not be operated after 2300 hours during testing and commissioning stage. Hence, this assessment would only consider the cumulative noise impact due to the operation of existing crematorium and newly proposed fixed plant under Phase 1 during daytime and evening (0700 to 2300 hours).
7.29 After the completion of the Project, the new crematorium will be operated for a maximum of 17 hours starting at 0930 every day.
Construction
Phase
7.30
The construction works of the Project
are divided into two phases – Phase 1 and Phase 2. Some construction tasks
under each phase are scheduled to be carried out concurrently. The construction noise assessment
was carried out on a monthly basis from the commencement of the Project to predict
the cumulative noise levels at representative NSRs.
7.31
In accordance with the EIAO-TM,
the methodology outlined in the GW-TM was used for the demolition/construction
noise assessment. The general approach is summarized below:
·
Locate the NSRs which would most likely be affected
by noise from the demolition/construction work
·
Determine the items of Powered Mechanical Equipment
(PME) for each discrete construction activity, based on available information
or agreed plant inventories
·
Assign sound power levels (SWLs) to the proposed
PME according to the GW-TM or other sources
·
Calculate distance attenuation and screening
effects to NSRs from notional noise source
·
Predict construction noise levels at NSRs in the
absence of any mitigation measures
·
Include a 3 dB(A) façade correction to the
predicted noise levels in order to account for the façade effect at each NSR.
7.32
Sound power levels (SWLs) of
the equipment were taken from Table 3 of GW-TM.
Where no sound power level (SWL) was given in the GW-TM, reference was
made to British Standard 5228: Part 1:1997 Noise Control on Construction and
Open Sites and previous similar studies or from measurements taken at other
sites in
7.33 The assessment was undertaken based on the assumption that all items of construction equipment are located at a notional noise source point for each phase of works and that all items of equipment are operating simultaneously.
Operation Noise
7.34
The fixed plant noise of the
proposed crematorium is assessed based on standard acoustic principles with
reference to the IND-TM.
7.35 According to the IND-TM, a correction factor for tonality, impulsiveness and intermittency shall be applied in assessing the fixed plant noise. It is anticipated that the operation of the proposed fixed plant will not involve any rapid changes in operating mode. Therefore, the correction factor for impulsiveness and intermittency was not applied in the calculations. For the tonal effect of the plant, as information is not available, a tonality correction of 6 dB(A) was applied in the calculations to represent the worst case scenario.
7.36 Given the fixed noise sources associated with the operation of existing crematorium would be controlled under the NCO, the ANL of 65 dB(A) for daytime/evening would therefore be adopted as the maximum noise level at representative NSRs due to the operation of existing fixed plant. Then, the predicted noise level at representative NSRs arising from the operation of new fixed plant under Phase 1 will be summed logarithmically to assess the cumulative operation noise impact during T&C stage of Phase 1.
7.37 In addition to the newly proposed transformer room, an existing electric sub-station (ESS) to the south of Cape Collinson Crematorium will be retained upon completion of the Project. Based on the on-site free-field noise measurement taken at 3.5m from the ECC, the sound pressure level (SPL) was 50.5 dB(A). Using the standard acoustic principle, the sound power level (SWL) of the existing ECC would be 69.4(A).
7.38 The tentative plant inventory and the corresponding SWLs have been presented in Appendix 7.5. As confirmed with the Project Proponent, the plant inventory used for prediction of operation noise impact is practical and realistic.
7.39 Noise impact was assessed on the basis of the following conservative assumptions:
·
All items of operational plant required for
operation of the proposed facilities to be located at the probable source
positions.
·
All items of operational plant to be operated simultaneously
during the operation period.
·
A +3 dB(A) façade correction was added to the
predicted noise levels to account for the façade effect at each NSR.
·
Noise impact at the nearest façades of the NSRs to
the source positions was assessed.
Level of Uncertainty
7.40 There would be some limitations such as the accuracy of the predictive base data for future conditions e.g. plant inventory for the proposed construction works and fixed plant for future operation. Uncertainties in the assessment of impacts have been considered when drawing conclusions from the assessment.
7.41 In carrying out the assessment, realistic worst case assumptions have been made in order to provide a conservative assessment of noise impacts. The construction noise impact was assessed based on conservative estimates for the types of plant and methods of working.
7.42 For operation noise assessment, being the worst case scenario, all items of equipment have been assumed to operate simultaneously during the operation period. A tonality correction of 6 dB(A) have been applied in the calculations to represent the worst case scenario. For determining the distance correction factors, the horizontal distances between the noise source positions and the NSRs were used for representing the worst level of the representative NSRs.
Prediction
and Evaluation of Environmental Impacts
Demolition/Construction Noise
7.43
For
normal daytime working hours, exceedences of the construction noise criteria (Leq
(30 minutes) 75 dB(A) for residential uses would be predicted at
representative NSRs in the absence of mitigation measures. Details of construction noise calculations
and results are presented in Appendix
7.6. Results show that the
predicted noise levels related to Phase 1 and Phase 2 of the Project are in the
range of 60 to 79 dB(A) and 61 to 81 dB(A) , respectively. A summary of the unmitigated construction
noise levels of the representative NSRs during normal daytime working hours
within the construction period of the Project is shown in Table 7.5. Noise mitigation measures would therefore be required to
reduce noise levels to the stipulated noise standards.
Table 7.5 Summary of Unmitigated Construction
Noise Levels at Representative NSRs During
|
Representative
NSRs |
Predicted
Unmitigated Construction Noise Levels during |
|
|
Phase
1 |
Phase
2 |
|
|
KTC |
66 - 79 |
64 - 78 |
|
SQ1 |
65 - 78 |
67 - 81 |
|
SQ2 |
62 - 76 |
63 - 78 |
|
SQ3 |
60 - 73 |
61 - 75 |
Operation Noise
7.44 The tentative plant inventory and the corresponding SWL are summarised in Appendix 7.5. To represent the worst case scenario, all items of equipment were assumed to operate simultaneously during the operation period and the directivity was not included in the calculation.
7.45 Due to the facade effect, a positive 3 dB(A) has been added to predict noise levels at the NSRs. For determining the distance correction factors, the distances between the probable source positions and the NSRs were considered. Regarding the fan noise impact, the distances between the louvers and the NSRs were considered in the assessment.
7.46 The new transformer will be housed/enclosed in a concrete structure. With reference to “Good Practices on Ventilation System Noise Control” published by Environmental Protection Department, facilities that would be enclosed in a concrete structure were assumed to have a 20 dB(A) reduction of noise emitted from the source due to transmission loss of the wall. Based on information provided by the Project Proponent, acoustic louvers would be provided for fan rooms and general exhaust fans for plant rooms. With reference to EIA Report for Siu Ho Wan Water Treatment Works Extension, a noise reduction of 20 dB(A) to the sound power level would be achieved with acoustic louvers. In cases where the louvers, a new transformer room and the existing ESS will be screened from the line-of-sight of NSRs by the structure of new crematorium itself or topographical features, a negative correction of 10 dB(A) would be applied to the predicted noise levels at the NSRs in accordance with the relevant Technical Memorandum. A positive 3 dB(A) for façade correction and 6 dB(A) for tonality correction have been added to predict noise levels at the NSRs.
Newly Proposed Equipment (Phase 1 and Phase 2)
7.47 According to the plant inventory for the proposed Project, the predicted noise levels at representative NSRs in the close vicinity of the Project are presented in Table 7.6. Details of the fixed plant noise calculations under unmitigated scenario are presented in Appendix 7.7. For newly proposed equipment under Phase 1 and Phase 2, while the predicted noise levels at SQ1 and SQ2 would exceed the daytime/evening planning noise criteria by 3 dB(A), the predicted noise levels at all representative NSRs would exceed the night-time planning noise criteria by 1 to 6 dB(A). Noise contribution from the existing electric sub-station to the overall noise level at the NSRs is insignificant. As a result, further specific noise mitigation measures would be required for the proposed fixed plant.
|
Representative
NSRs |
Planning
Noise Criteria, Leq(30-min) dB(A) |
Predicted
Noise Level, Leq(30-min) dB(A) |
|
|
Daytime
& Evening (0700 - 2300 hours) |
Night-time (2300
– 0700 hours) |
||
|
KTC |
56 |
50 |
54 |
|
SQ1 |
53 |
50 |
56 |
|
SQ2 |
51 |
48 |
54 |
|
SQ3 |
55 |
50 |
51 |
Transitional Operation Noise Impact (T&C of
Phase 1 Cremators)
7.48 During testing and commissioning of new cremators under Phase 1, the existing crematorium would be still operative for the public use. As mentioned in Section 7.36, the ANL of 65 dB(A) for daytime/evening would be adopted as the maximum noise level at representative NSRs due to the operation of existing fixed plant. With reference to Appendix 7.10, the predicted mitigated operation noise levels at representative NSRs due to operation of new equipment under Phase 1 would range from 41 to 46 dB(A) which are 19 to 24 dB(A) below the relevant ANL of 65 dB(A). Thus, it is anticipated that the noise contribution from the new fixed plant under Phase 1 to the cumulative noise impact at representative NSRs would not be significant (see Table 7.7). During T&C period of Phase 1, only 2 new cremators will be tested at any one time together with the existing cremators, therefore the noise contribution from the new fixed plant to the cumulative noise impact at the NSRs would be less than that presented in Table 7.7.
Table 7.7 Predicted Operation Noise Levels During Transitional Period
(Existing Equipment + New Equipment under Phase 1)
|
Representative |
Predicted Noise Level, Leq(30-min), dB(A) |
||
|
NSRs |
Existing Equipment |
New Equipment under Phase 1 |
Overall |
|
KTC |
65 |
46 |
65 |
|
SQ1 |
65 |
45 |
65 |
|
SQ2 |
65 |
44 |
65 |
|
SQ3 |
65 |
41 |
65 |
Mitigation of Environmental Impacts
Demolition/Construction Noise
7.49 In order to reduce the excessive noise impacts at the affected NSRs during normal daytime working hours, use of quiet powered mechanical equipment for excavator/loader, soil nailing drilling machine, rock dowel drilling machine, bulldozer, dump truck and crawler mounted rock drill have been recommended (see Appendix 7.8) and has been confirmed by the Engineer as being practicable in completing the works within scheduled timeframe. The Contractor may be able to obtain particular models of plant that are quieter than the PMEs given in GW-TM. It is considered too restrictive to specify that a Contractor has to use specific items of plant for the construction operations. It is practical to specify the total SWL of all plant to be used on site so that the Contractor is allowed some flexibility to select plant to suit his needs.
7.50
In
this assessment, the recommended quiet PME are taken from the BS 5228: Part 1:
1997, and the PME are known to be available in
7.51 As shown in Appendix 7.9, with the use of quiet equipment, the overall noise levels at representative NSRs would be reduced by up to 7 dB(A). The predicted mitigated construction noise levels at all representative NSRs, ranging from 60 to 74 dB(A) for Phase 1 and 61 to 75 dB(A) for Phase 2, would comply with the EIAO-TM construction noise limit of 75 dB(A). A summary of mitigated noise levels during normal daytime working hours at representative NSRs is presented in Table 7.8.
Table 7.8 Summary of Mitigated Construction Noise
Levels at Representative NSRs During
|
Representative
NSRs |
Predicted
Mitigated Construction Noise Levels during |
|
|
Phase
1 |
Phase
2 |
|
|
KTC |
66 - 74 |
64 - 72 |
|
SQ1 |
65 - 74 |
67 - 75 |
|
SQ2 |
62 - 71 |
63 - 72 |
|
SQ3 |
60 - 69 |
61 - 69 |
7.52 In addition to quiet PME and movable noise barriers, good site practice listed below is recommended to further minimise the noise nuisance.
·
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.
Operation Noise
7.53 As mentioned in Section 7.47, the predicted noise levels at all representative NSRs would exceed the night-time noise criteria. A total of 10 radiators for cremators, which are located on the upper roof of the crematorium, would be the dominant noise sources causing noise exceedance at these affected NSRs. In this regard, 2.5m high noise barriers as shown in Figure 7.2 have been proposed to surround the radiators, while the heat dissipation of the radiators would not be hindered. Besides, the noise barrier would be lined with sound absorbing material at the surface of the barrier facing the noise source to further enhance the noise reduction effectiveness. It is anticipated that a noise reduction of 10 dB(A) would be achieved with the noise barrier in place.
Newly Proposed Equipment (Phase 1 and Phase 2)
7.54 As shown in Table 7.9, the predicted noise levels at all representative NSRs would comply with both the daytime and night-time planning noise criteria with the noise barriers for radiators in place. Details of the fixed plant noise calculations under mitigated scenario are presented in Appendix 7.10.
|
Representative
NSRs |
Planning
Noise Criteria, Leq(30-min) dB(A) |
Predicted
Noise Level, Leq(30-min) dB(A) |
|
|
Daytime
& Evening (0700 - 2300 hours) |
Night-time (2300
– 0700 hours) |
||
|
KTC |
56 |
50 |
48 |
|
SQ1 |
53 |
50 |
49 |
|
SQ2 |
51 |
48 |
46 |
|
SQ3 |
55 |
50 |
43 |
Transitional Operation Noise Impact (T&C of
Phase 1 Cremators)
7.55 With the 2.5m high noise barriers for radiators in place, the predicted cumulative noise levels at all representative NSRs during T&C stage of Phase 1 would comply with the relevant ANL of 65 dB(A).
Evaluation of Residual Impacts
Demolition/Construction
Noise
7.56
With
the use of silenced PME, the predicted noise levels at representative NSRs for
Phase 1 and Phase 2 of the Project would comply with the noise limit of 75
dB(A). There would be no residual noise impact.
Operation Noise
7.57 Based on the information provided by the Project Proponent, acoustic louvers would be provided for fan rooms and general exhaust fans for plant rooms. Besides, 2.5m high noise barriers have been proposed to surround the radiators which are located on the upper roof of the crematorium. With such proper designs, no adverse residual operation noise impact arising from the Project is expected.
Environmental
Monitoring and Audit
7.58 It is recommended to establish an Environmental Monitoring and Audit (EM&A) programme for control of construction noise. The recommended mitigation measures should be incorporated into the EM&A programme for implementation during the construction period. Details of the programme are provided in a stand-alone EM&A Manual.
7.59
The EIA findings confirmed that
proper designs of the crematorium would control the potential noise impact at
noise sensitive receivers within acceptable levels, operation noise monitoring
is not considered necessary. Nevertheless, noise measurements at
Demolition/Construction Noise
7.60
This assessment has predicted the construction noise
impacts of the Project during normal daytime working. The predicted unmitigated
noise levels at representative NSRs would range from 60 to 79 dB(A)
for Phase 1 and 61 to 81 dB(A) for Phase 2. With
the use of quiet PME for excavator/loader, soil nailing drilling
machine, rock dowel drilling machine, bulldozer, dump truck and crawler mounted rock drill, the noise levels at all
representative NSRs would comply with the construction noise limit of 75 dB(A).
7.61
A construction noise EM&A programme is recommended
to check the compliance of the noise criteria during normal daytime working
hours.
Operation Noise
7.62
The
noise impact associated with the operation of the Project was assessed. For newly proposed equipment under Phase 1 and Phase 2, while the
predicted noise levels at SQ1 and SQ2 would exceed the daytime/evening planning
noise criteria by 3 dB(A), the predicted noise levels at all representative
NSRs would exceed the night-time planning noise criteria by 1 to 6 dB(A).
7.63
To mitigate the noise impact at
the affected NSRs, 2.5m high noise barriers have been proposed to surround the
radiators. Besides, the noise barrier would be lined with sound absorbing
material at the surface of the barrier facing the noise source to further
enhance the noise reduction effectiveness. With such noise barriers in place,
the predicted noise levels at all representative NSRs would comply with both
the daytime and night-time planning noise criteria. No residual operation noise
impact arising from the Project is anticipated.
7.64
For the concurrent operation of
existing fixed plant and newly fixed plant during T&C stage of Phase 1, the
predicted cumulative noise levels at all representative NSRs would comply with
the relevant daytime/evening ANL of 65 dB(A) with the 2.5m high noise barriers
for the radiators in place.
7.65
Proper design of the proposed
crematorium would control the potential noise impact at noise sensitive
receivers within acceptable levels, operational noise monitoring is not
considered necessary.
Nevertheless, noise measurements at