14.6 Waste Management
Implications
14.7 Land Contamination
Impact
14.9 Landscape and
Visual Impact
14.10 Cultural Heritage
Impact
14.11 Environmental
Monitoring and Audit
The Project is a designated project in
accordance with Item C.5 of Part I of Schedule 2 of the EIAO, which specifies
“A typhoon shelter designed to provide moorings for not less than 30 vessels”.
Table 14.1 Summary
of Environmental Impacts Associated with the Project
Environmental Issue |
Sensitive
Receivers/ Assessment Points |
Impact Prediction
Results |
Relevant Standards/
Criteria |
Extents of
Exceedances |
Impact Avoidance
Measures/ Mitigation Measures |
Residual Impacts |
Air Quality |
|
|
|
|
|
|
Construction Phase |
23 assessment points |
No adverse air quality
impacts at the ASRs are expected during construction of temporary typhoon
shelter |
EIAO-TM and Air
Quality Objective |
Nil |
Requirements of the Air Pollution Control (Construction Dust) Regulation The operated dredgers should be
regularly maintained to minimise emissions |
Nil |
Operational Phase |
Not Applicable |
In view of the project nature, no adverse air quality
impact during the operation phase would be anticipated. |
Not Applicable |
Nil |
Not Applicable |
Nil |
Noise |
|
|
|
|
|
|
Construction Phase |
N15 and N17 |
Predicted noise levels
would be in the range of 72 to 74 dB(A). |
Domestic premises:
75dB(A) |
Domestic premises: No
noise exceedence |
Use of quiet equipment
to further mininise construction noise impact |
Nil |
Operational Phase |
Not Applicable |
Considering the nearest noise sensitive receivers, |
Not Applicable |
Nil |
Not Applicable
|
Nil |
Water Quality |
|
|
|
|
|
|
The major issues would be the potential SS elevations in the water
column during dredging for construction of the TBW. The TBW may also affect the dispersion
pattern of the sediment plume potentially generated from dredging under other WDII works including
those within the existing CBTS during construction of
the CWB tunnel. |
All water sensitivity
receivers in |
The model results
indicate exceedances of WSD water quality (SS) criterion for flushing water
intakes (at |
WSD water quality
criterion for SS: < 10 mg/l Target SS level at
Admiralty Centre and MTRC cooling water intakes: < 40 mg/l Sedimentation rate at
corals: < |
Maximum SS levels
predicted at the WSD flushing water intakes ranged from 12.5 mg/l to 51.1
mg/l. Maximum SS levels
predicted at Admiralty Centre and MTRC cooling water intakes ranged from 40.4
mg/l to 100.8 mg/l. No exceedance for the
sedimentation rate was predicted |
Restriction on the
maximum dredging rates at the sewage pipelines zone, water mains zone, TWB,
HKCEC Stage 1 & 3 as well as the western seawall
of WCR1 which is close to the WSD intake at Wan Chai; Deployment of silt
curtains around seawall dredging and seawall trench filling in NPR, TCBR, WCR
and HKCEC areas. Deployment of silt screens at selected seawater
intakes |
Nil |
Full compliance with
the assessment criterion for sedimentation rate |
||||||
|
||||||
Change of dispersion capacity for polluted storm water in the existing embayment of
CBTS after the placement of the TBW |
Cooling water intakes inside the existing CBTS |
The TBW operation would not cause unacceptable
impacts in the existing embayment of CBTS |
Relevant WQO for
marine water: |
Some local
exceedances of the TIN and UIA levels are predicted at the CBTS. However, these exceedances were not
contributed by the Project as similar degree of exceedances was also
predicted under the pre-construction scenario. The associated water quality impact is
anticipated to be limited as CBTS has low marine ecological value and the
plume of UIA would be confined within the typhoon shelter. |
No mitigation measures
are considered necessary. |
Nil |
TIN level: <0.4
mg/l for annual mean |
||||||
UIA level: <0.021
mg/l for annual mean |
||||||
Depth-averaged DO
level: > 4 mg/l for 10th percentile |
||||||
Bottom DO level: |
||||||
Waste Management Implications |
|
|
|
|
|
|
Construction Phase |
Not applicable |
Main waste: dredged marine sediment with a total volume of approx. |
1. Waste Disposal Ordinance (Cap.
354) |
Not applicable |
Refer to Table 13.4 |
Nil |
|
|
Other wastes: general refuse from
the workforce; chemical waste from plant and equipment maintenance; and
C&D material from excavation works and the demolition of existing
structures. |
2. Waste Disposal (Chemical Waste) (General)
Regulation (Cap. 354) |
|
|
|
|
|
3. Land (Miscellaneous Provisions)
Ordinance (Cap. 28) |
|
|
|
|
|
|
4. Public Health and Municipal
Services Ordinance (Cap. 132) - Public Cleansing and Prevention of Nuisances
Regulation |
|
|
|
|
|
|
|
5. Annexes 7 & 15 of EIAO TM |
|
|
|
Land Contamination Impact |
|
|
|
|
|
|
Construction Phase |
Construction Workers
via direct ingestion of and dermal contact with contaminated soils. |
No land contamination
impact is expected. |
ProPECC PN3/94 - “Contaminated Land Assessment and
Remediation” “Guidance Notes for Investigation and
Remediation of Contaminated Sites of: Petrol Filling Stations, Boatyards, and
Car Repair /Dismantling Workshops |
None |
None |
Nil |
Marine Ecological Impacts |
|
|
|
|
|
|
Construction Phase |
Ecological resources
in the assessment area |
-
Temporary loss of |
Not applicable |
Not applicable |
As no adverse ecological impact on marine habitats
and associated wildlife is predicted, no necessary mitigation measure
specific for marine ecology is considered as required in this
assessment. The mitigation
measures recommended in the water quality impact assessment to control water
quality would also serve to protect marine ecological resources from indirect
impacts and ensure no adverse impact on marine life would be resulted from
this designated project.
|
Not expected. |
|
|
Changes in water
quality -
More than 30% increase of SS at the immediate vicinity outside
reclamation area -
Insignificant elevation of SS at far-field sensitive receivers -
Level of TIN is predicted to be slightly higher than WQO standard at
several locations immediately outside reclamation area -
Minimum depth-averaged DO at HKCEC is predicted to be slightly lower
than 4.0 mg/L. |
(See water quality
assessment) |
(See water quality
assessment) |
||
|
|
Disturbance impact |
Not applicable |
Not applicable |
|
|
Operational Phase |
Ecological resources
in the assessment area |
- No direct or indirect impact on marine ecological resources is predicted. |
|
|
|
|
Landscape and Visual Impact |
|
|
|
|
|
|
Construction Phase |
All Landscape Resources / Landscape
Character Areas and Visual Sensitive Receivers within the study area |
The impact on the |
Not applicable |
Not applicable |
Control of night-time lighting. |
Landscape Impacts
The temporary typhoon shelter
will not affect any existing trees.
It is considered that the
residual impacts on
|
|
|
|
|
|
|
Visual Impacts
During
construction, with implementation of mitigation measures, there will be some moderate negative
visual impact on the VSRs in the front row of high rise buildings along the
waterfront from Central to North Point.
Residual impacts VSRs further away the
|
Operational Phase |
All Landscape Resources / Landscape Character Areas and Visual Sensitive Receivers within the study area |
There will be no landscape and visual impacts during operation. |
Not applicable |
Not applicable |
Not applicable |
The existing
landscape characters will not be affected during operation. During operation,
there will be no impacts on all existing and planned VSRs. |
Cultural Heritage Impact |
|
|
|
|
|
|
Construction Phase |
Marine archaeological
resources in |
Since there is no archaeological
material present within the study area, no adverse cultural heritage impact
is expected. |
1.
Antiquities and Monuments Ordinance (Cap.53) 2.
Environmental Impact Assessment Ordinance (EIAO) (Cap. 499,
S.16) 3.
Technical Memorandum on the Environmental Impact Assessment
Process (EIAO-TM) |
Not applicable |
No further
archaeological investigation or mitigation measures is required |
Nil |
|
|
|
4.
Guidance Notes on Assessment of Impact on Sites of Cultural Heritage
in Environmental Impact Assessment Studies (GN-CH) |
|
|
|
|
|
|
5.
6.
Marine Archaeological Investigation Guidelines. |
|
|
|
Table
14.2 Summary
of Key Environmental Outcomes/ Benefits
Issue |
Environmental Outcomes/Benefits |
The Project |
Requirements: The construction of the Trunk Road tunnel beneath the existing CBTS will temporarily affect the existing moorings. To maintain the operation of the CBTS during the construction period, it is necessary to reprovision a temporary typhoon shelter in the vicinity of the existing one. |
|
Benefits: The temporary reprovisioning of the affected
CBTS to the temporary typhoon shelter at the north of the existing one
maintains the current provision of mooring area at |
|
Potential
consequences without the Project:
Should the temporary typhoon shelter not be temporarily
reprovisioned, the existing mooring area at the CBTS will be temporarily lost
during construction of the Trunk Road. In environmental terms, water quality at |
Development
Alternatives |
As alternative to temporarily
reprovisioning the typhoon shelter to the north of the existing one, which is
the nearby available location, affected vessels sheltered at CBTS could be
temporarily relocated to other off-site typhoon shelters. These are very far
away from the |
Construction Air
Quality Impact |
Environmental
benefits of environmental protection measures recommended: Potential marine traffic emissions from the
dredgers would be expected.
However, only two dredgers would be operated at the work site, the
associated emission should be limited.
Under normal operation, equipment with proper maintenance is unlikely
to cause significant dark smoke emissions and gaseous emissions are expected
to be minor. Thus, the AQOs are not expected to be exceeded. Notwithstanding, plant should be regularly
maintained to minimise emissions. |
|
Compensation
areas included: Not
required Population
and environmental sensitive receivers protected: Existing air sensitive receivers within 500m of the project boundary. |
Operational Air
Quality Impact |
Environmental
benefits of environmental protection measures recommended: In view of the project nature, no adverse air quality impact during the
operation phase would be anticipated. Compensation
areas included: Not
required Population
and environmental sensitive receivers protected: Existing and planned air sensitive receivers within |
Construction Noise
Impact |
Environmental
benefits of environmental protection measures recommended: The predicted noise levels at representative NSRs would be in the range of 72 to 74 dB(A) in the absence of mitigation measures. Notwithstanding this, in order to further minimise the noise impacts at the NSRs, mitigation measures such as adopting quiet powered mechanical equipment are recommended. |
|
Compensation
areas included: Not required. |
|
Population
and environmental sensitive receivers protected: Noise
sensitive receivers within 300m of the project boundary. |
Operation Noise
Impact |
Considering the nearest noise sensitive
receivers, |
Water Quality Impact |
Environmental
benefits of environmental protection measures recommended: The
assessment of hydrodynamic and water quality impacts associated with the
proposed TBW have been assessed using the Delft3D model. The major water
quality impact associated with dredging for construction of the TBW is the
elevation of SS within the marine water column. The TBW may also affect the dispersion
pattern of the sediment plume potentially generated from dredging within the
existing CBTS during construction of the CWB tunnel. Provided the recommended
mitigation measures are implemented, including restriction on the maximum
dredging rates, the deployment of silt curtains at the specified dredging
areas, and installation of silt screens at seawater intakes, there would be no unacceptable residual water
quality impact due to the proposed dredging works. In terms of the potential change of dispersion capacity for the
polluted storm waters in the existing embayment of CBTS after the placement of the TBW,
the model results indicated that no unacceptable water quality impacts would
be expected during the
TBW operation.
Compensation
areas included: Not required. Population
and environmental sensitive receivers protected: Seawater intakes along the waterfront of |
Waste Management
Implications |
Environmental benefits of environmental protection measures recommended: With the implementation of the recommended mitigation measures and practices, potential air, odour, noise, water quality for the handling, transportation and disposal of the identified waste arisings, no adverse environmental impacts are expected. Limited amount of refuse and debris may be
unintentionally brought from the site into the harbour during heavy rains or
typhoons. Given that the Project would not worsen the shoreline configuration
and the implementation of appropriate control measures during construction
phase, it is considered that the future quantity of refuse to be found along
the shoreline would be similar if not better than the existing situation.
With the implementation of a refuse collection system within the project
area, no insurmountable environmental impact with regard to floating refuse
would be anticipated during the construction phase, or after completion of
the Project. Compensation
areas included: Not required. Population and environmental sensitive
receivers protected: · Water quality, air, and noise sensitive receivers at or near the Project site, the waste transportation routes and the waste disposal site. |
|
|
Land Contamination
Impact |
Environmental benefits of environmental protection measures recommended: No potential contaminative land uses were identified within the Study Area. As such, adverse land contamination impacts associated with the construction and operation of the Project is not expected. Compensation
areas included: Not
required. Population and environmental sensitive receivers protected: No construction worker would be affected. |
Marine Ecological
Impact |
Environmental benefits of environmental protection measures
recommended: The
benthic, intertidal and subtidal habitats within the affected area are of
very low ecological value. Hence, adverse direct ecological impact caused
from temporary reclamation works is not expected. Water quality and noise
control measures (as described above) would minimise indirect impact on
marine habitats and associated flora and fauna due to change in water quality
and noise environment during the construction phase.
Compensation
areas included: Construction of about Population
and environmental sensitive receivers protected: Ecological resources in the assessment area. |
Landscape and Visual Impact |
Environmental benefits of environmental protection measures recommended: ·
A temporary typhoon shelter
of approximately |
|
· It is considered that the residual impacts on |
|
·
With implementation of
mitigation measures during construction, there will slight negative visual
impact on the VSRs in the front row of high rise buildings along the
waterfront from Central to North Point.
Residual impacts VSRs further away the |
|
Compensation
areas included: Approximately
Population
and environmental sensitive receivers protected: Existing and
planned Landscape Resources , Landscape Character Area and VSR at and near
the project site. |
Cultural Heritage
Impact |
Environmental
benefits of environmental protection measures recommended: Since there are no marine archaeological
resources within the study area that would be affected by the project, marine
archaeological impact due to the construction activities is not expected. The
current project design would avoid the potential impact on the Kellett Island
Archaeological Site at RHKYC and Noonday Gun at CBTS. No environmental protection measure is
required. Compensation
areas included: Not required. Population
and environmental sensitive receivers protected: Potential archaeological resources, and
historical buildings and structures within the project area. |
Operational Phase