13.1
This EIA Report has provided an assessment of the potential
environmental impacts associated with the construction and operation of the WIL
Project, based on the preliminary engineering design information available at
this stage.
13.2
The assessment has been conducted, in accordance with the
EIA Study Brief (No. ESB–130/2005) under the EIAO for the Project, covering the
following environmental issues:
n
Airborne noise impact
n
Ground-borne noise impact
n
Landscape and Visual Impacts
n
Cultural Heritage Impact
n
Waste Management Implications
n
Land Contamination
n
Water Quality Impact
n
Air Quality Impact (Construction
Stage)
n
Hazard to Life
13.3
The findings of this EIA study have determined
the likely
nature and
extent of environmental impacts predicted to arise from the construction and
operation of the Project. During the EIA
process, environmental control measures have been identified and incorporated
into the planning and design of the WIL Project, to ensure compliance with
environmental legislation and standards during both the construction and
operation phases. The Implementation
Schedules listing the recommended mitigation
measures are
presented in Section 14.
13.4
Overall, the EIA study for the WIL has predicted that the
Project, with the implementation of the mitigation measures, would be
environmentally acceptable with no adverse residual impacts on the population
and environmentally sensitive resources.
Table 13.1 summarises the environmental outcomes/benefits that
have accrued from the environmental considerations and analysis during the EIA
process and the implementation of environmental control measures of the
Project. Environmental monitoring and
audit requirements have been recommended, where necessary, to check
on project compliance of environmental legislation and standards.
Table 13.1 Summary of Key
Environmental Outcomes / Benefits
Area/Issue |
Environmental Outcomes / Benefits and Mitigation Measures |
The
Project |
The Project comprises the following
elements: ·
Approximately 3km of underground railway from Sheung
Wan via Sai Ying Pun and University of Hong Kong to Kennedy Town ·
An overrun tunnel extending from KET Station to
the Ex-police Quarters site. ·
Three stations: Kennedy Town Station (KET
Station); University Station (UNI Station); and Sai Ying Pun Station (SYP Station) ·
Ventilation shafts, cooling towers and chillers
for stations and railway tunnel. Overnight storage of explosives is
needed for the construction of the underground railway facilities. A temporary project specific magazine is
proposed at an abandoned site at The excavated materials arising from
the WIL construction would reach ground level via two main construction
shafts located at the Kennedy Praya site and the |
Environmental
Benefits of the Project |
The
use of electrically powered trains which are emission free would enable WIL
to become not only an efficient but environmentally friendly mass carrier. The
WIL sited within intensive developments and employment centres would help
encourage the usage of railways and thereby reduce reliance on road-based
transport. The
capacity of the existing heavily-loaded road networks could be freed up,
which would help to improve the current traffic congestion problems at the
Western District. This would also help
to reduce vehicular noise, air emissions and improve overall environmental
quality. |
Environmentally
Friendly Design Recommended to Avoid Environmental Problems |
Design
measures have been taken to preserve the tree walls
in the Kennedy
Town Playground and along All
The
entire WIL alignment will be constructed underground. Airborne train noise impacts and the need
for erecting noise barriers and enclosures could be avoided. Given the deep
underground tunnel,
ground-borne train noise impacts would be minor and could be alleviated to
acceptable levels through the use of vibration
mitigating trackform. Barges are to be employed for
transporting majority of the surplus C&D material from the site formation
for the An enclosed
conveyor belt system is proposed for conveying the excavated material from
the construction
shaft down to the barging point at the |
Population
and Environmentally Sensitive Areas Protected |
With
the adoption of environmentally design mentioned above, major environmentally
sensitive receivers protected would include tree walls in the Kennedy
Town Playground and along Potential
construction dust and noise impacts associated with the transport of spoil on
air and noise sensitive receivers in the Western District could be minimised
with the use of barges for transporting majority of surplus spoil. There
would not be any airborne train noise impacts on the noise sensitive uses
within in the Project boundary as the entire WIL alignment would be in
tunnel. |
Airborne Noise |
Unmitigated cumulative construction noise levels
due to the proposed works for the construction of WIL were predicted. The assessment results indicated that the
proposed works of the Project would result in noise exceedance (up to 22dB(A))
of the EIAO-TM construction noise criteria for non-restricted hours. In view of this, mitigation measures including
good site practices, quieter plant, silencer, movable noise barrier, temporary noise barrier, noise
enclosure, noise insulating fabric, “Noise Control Curtain”, noise insulating
cover, acoustic enclosure and decking over the excavation area/lift shaft were recommended
to reduce the noise levels. After
mitigation, noise levels at most of the NSRs are predicted to comply with the EIAO-TM daytime construction noise
criterion. However, some NSRs including KET 3-5, KET7, KET9,
UNI1, UNI10-12, SYP1-5, SYP 7-13, SYP16 and GT5-6 located
in close proximity to the works areas would still be exposed to noise
levels exceeding the EIAO-TM noise criteria for a short period of time. The ITR has been considered for the affected NSRs. With reference to the criteria developed in
the East Rail Extension Hung Hom to
Tsim Sha Tsui EIA Final Report (ERE-EIA), the criteria would be dependent
on the severity of the residual noise impact and duration of noise exceedance
after implementing all practical direct mitigation measures. NSRs which were
considered to be eligible for ITR provision were identified. During operation phase, predicted noise levels at all NSRs
arising from the fixed plant of the Project would comply with the EIAO-TM
criteria providing fixed plant is designed to comply with NCO. In this case, no adverse fixed plant noise
impacts would be expected. |
Groundborne
Noise |
During construction phase, the drill and blast alternative is not considered with respect to noise annoyance, as the duration of blasting is very short and infrequent. No assessment has been carried out regarding noise annoyance impacts within any of the identified sensitive receivers. Moreover, the TBM construction method is viable for tunnel formation along the WIL, with possible operational prohibition during night time hours near SHW and UNI stations. Ground-borne train noise has been predicted at representative sensitive receivers. Results indicated that vibration mitigating trackform would be required at some sections of the WIL alignment as shown in Figures 4.6-4.8 in order to provide sufficient attenuation to meet the stipulated criteria, and there would not be any adverse residual impacts. |
Landscape and Visual |
Potential landscape and visual impacts
during construction and operation of WIL would be partly reduced after
applying mitigation measures such as tree protection particularly for the The permanent loss of children play facilities and landscape sitting out area for local residents and neighbourhood nearby cannot be mitigated, even though the LCSD playground will be compensated at the existing Kennedy Town Swimming Pool site. Besides, the tree pruning works will deform and scar several nice specimens during the transplanting process. The overall landscape and visual
quality would be further enhanced by applying attractive streetscape design
with provision of tree planting. With implementation of mitigation measures, residual
impacts of the WIL are considered to be acceptable, with reference to the
criteria defined in Annex 10 of the EIAO TM. |
Cultural Heritage |
The WIL project would have no adverse impacts on the cultural heritage resources in the study area, during both construction and operation phases, with the implementation of the archaeological watching brief, recommended vibration and landscape/visual mitigation measures. |
Waste management implications |
Construction
waste arisings have been identified based on the proposed construction
activities and would comprise C&D material, general refuse and chemical
waste. Provided that the identified
waste arisings are to be handled, transported and disposed of using approved
methods and the recommended good site practices are to be followed, adverse
environmental impacts would not be expected during the construction
phase. The
waste management practices of waste arisings generated during the operational
phase of the WIL would be similar to arrangements currently in operation on
the existing Island Line and would pose no impact. |
Land Contamination |
Based on a review of historical/current land uses in respect of land contamination, including a desk-top review and site inspection, around the proposed WIL alignment and Works Areas, no land contamination issues in relation to the WIL construction was envisaged.
|
Water quality |
Water quality impacts from construction
activities would be controlled by implementing the recommended
mitigation measures, such as control measures on site runoff and drainage
from the works areas to minimise construction runoff, and particularly on-site
treatment of tunnelling wastewater prior to discharge. The operational water quality for
track run-off and tunnel seepage would have no adverse water quality impact
provided that mitigation measures are incorporated in the design. The fresh water cooling system for the WIL
would not be expected to result in unacceptable impacts on water
quality. Sewage and wastewater effluents
arisings from the operation of the stations would be discharged to the foul
sewer and would not cause adverse water quality impact. |
Hazard to Life |
A QRA has been carried
out to assess the hazard to life issues arising from the storage, use and
transport of explosives in the proposed underground magazine and the
construction sites of the Project. Assessment results
indicated that the individual and societal risk is within the acceptable
limit of the risk guidelines in the Annex 4 of EIAO-TM. |
Air quality (Construction Stage) |
Potential dust impacts would be generated from demolishment of some existing structures, excavation activities, material handlings, wind erosion, temporary stockpiles, spoil removal, material delivery, operation of temporary magazine site, barging points and rock crushing plants during the construction phase. Fugitive dust impacts would be controlled by implementation of dust suppression measures stipulated in Air Pollution Control (Construction Dust) Regulation, good site practices and proposed mitigation measures. The predicted TSP levels at the representative ASRs would comply with the statutory requirement. |