14.1.2
Environmental benefits of the Project and the environmental protection
measures recommended: The sewage treatment level of
the Cheung Chau STW will be upgraded from primary to secondary and the capacity
will be expanded to cope with the population growth and future
developments. Discharge of low quality
effluent to the receiving water body will be reduced and hence will improve the
coastal water quality of Cheung Chau.
Furthermore, hygiene problems within the catchment areas arising from the
use of septic tanks will be largely relieved with provision of public sewers to
currently unsewered villages, where practicable.
14.1.3
Population and environmentally sensitive area protected: The marine waters near the Project site are protected by the improved
treatment standard and treatment capacity of the Cheung Chau STW and the
elimination of overflow from Pak She SPS.
The residential areas and village houses which are currently unsewered
are also protected by provision of new sewers under this Project.
14.1.4
Environmentally friendly designs recommended: The Deep Sewer Option instead of Kwun Yam Wan
SPS would reduce impacts arising from the construction of a new SPS adjacent to
Kwun Yam Wan Beach and the need of private land resumption. Hand Shield construction method would be
proposed for the deep sewers construction to reduce the extent of road opening
works along Tung Wan Road and Cheung Chau Sports Road. For Cheung Chau STW and Pak She SPS, the
provision of standby parts and standby power sources improve the reliability of
the sewage treatment and disposal system, while the provision of deodorizing
units could reduce the possible odour impact to adjacent sensitive
receivers. In the design of Cheung Chau
STW, non-potable reuse of treated effluent within the STW site will be proposed
to reduce the consumption of potable water.
Energy efficiency measures such as adoption of solar panel, skylight and
natural ventilation, etc. will also be explored to reduce energy consumption.
The facilities of the upgraded Cheung Chau STW are so arranged as to minimize
disturbance to the existing trees within the STW and more trees will be planted
within the upgraded STW to enhance greenings and improve the visual
appearances.
14.1.5
Key environmental problems avoided:
Potential
deterioration of effluent quality of the existing Cheung Chau STW due to ageing
problem of the facilities will be avoided by the proposed upgrading of the
sewage treatment level and increasing the existing capacity of the STW. The hygiene problems arising from the use of
septic tanks will also be largely relieved by the provision of public sewers to
currently unsewered village, where practicable.
Furthermore, potential sewage overflow to Cheung Chau receiving water
body will be eliminated by the proposed upgrading works for Pak She SPS.
14.1.6
Compensation areas: There is no significant habitat
loss as a consequence of the Project.
Thus no specific compensation areas are required.
14.2
Overall Conclusions
14.2.1
The EIA Report has provided an assessment of the potential
environmental impacts associated with the Project. All environmental issues including air
quality, noise, water quality, waste management, land contamination, ecology,
fisheries, cultural heritage and landscape and visual have been undertaken in
accordance with the EIA Study Brief (No. ESB-212/2009).
14.2.2
The nature and extent of different environmental impacts arising from
the construction and operation of the Project have been addressed and
quantified in the previous sections. In
addition, a summary of assessment findings of these individual issues is
provided at the end of each section.
Appropriate mitigation measures have also been recommended for
incorporation into the design, construction and operation phases of the Project
for compliance of relevant environmental legislation and standards. The Implementation Schedules of the
recommended mitigation measures are provided in Section 13.
14.2.3
In conclusion, the Project would provide an overall improvement in
water quality for marine waters near the Project site. It would comply with environmental legislation
and standards with the implementation of the recommended mitigation measures
and good site practice. An EM&A
programme has also been recommended to be implemented before and during the
construction and operation phases of the Project to check the implementation
and effectiveness of the recommended mitigation measures.