Air quality impacts from the
construction works would mainly be due to construction dust from excavation,
materials handling, filling activities and wind erosion. With the implementation of recommended dust
suppression measures and mitigation measures specified in the Air Pollution Control
(Construction Dust) Regulation and EM&A
programme, dust impact on air sensitive receivers is anticipated to be minimal.
For the operation phase, cumulative
air quality impact arising from vehicular emissions was assessed using air
quality modelling. The following were included
in the assessment:
Vehicle emissions from traffic on open
Vehicle emissions from: tunnel portals
of the WCR, Eastern Harbour Crossing (EHC), Lei Yue Mun underpass; portals of
the deck-over at Sceneway Garden; portals of proposed full enclosures along the
WCR; portals of the tunnel section of link roads of WCR/ CBL/ Road P2
interchange and the covered sections of Road P2.
Vehicle emissions from idling traffic
near the WCR and EHC toll plazas.
Vehicle emissions from the EHC vent
shafts and WCR ventilation exhaust buildings.
Emissions from industrial chimneys at
Emissions from the landfill gas
flaring plants located at Sai Tso Wan Landfill and TKO Stage I & Stage
Air quality modelling took into
account the effect of the recommended roadside noise barriers and
enclosures. With the provision of the
recommended tunnel ventilation systems for the WCR (relocation of the
Mid-Ventilation Building and extraction of 90% tunnel emission from the WCR
westbound tunnel through vent shaft facing upward direction, and extraction of
70% tunnel emission from WCR eastbound tunnel through vent shafts facing upward
direction at Eastern Portal Ventilation Building at TKO area), the predicted
air quality impacts at all representative ASRs would satisfy the AQO.
The air pollutant concentrations within
the WCR tunnel would meet the requirements of the Environmental Protection
Department (EPD) guideline given that the tunnel would be provided with an
effective ventilation system.
Odour impacts from the proposed sewage
pumping station located at the southern end of TKO Stage 1 Landfill near Area
86 are expected to be minimal, with the installation of high efficiency
deodourization units. Cumulative odour
impacts from the existing preliminary wastewater treatment works at Area 85 are
not expected due to large separation distance.
The assessment predicted that with the
use of silenced equipment, and the use of movable noise barriers for some construction
plant, noise levels at all of the representative Noise Sensitive Receivers
(NSRs) would comply with the construction noise criteria.
The potential road traffic noise
impacts were assessed for the worst-case traffic flows in Year 2016 (prior to
the opening of the WCR) and Year 2031 (15 years after opening of the WCR). Noise levels at most of the NSRs were
predicted to exceed the traffic noise criteria established in the Technical Memorandum on
Environmental Impact Assessment Process under the Environmental Impact
Assessment Ordinance (EIAO-TM). Therefore, direct mitigation measures such
as use of low-noise road surfacing materials, roadside barriers and enclosures,
have been proposed to be implemented on the ‘new’ roads to alleviate the
traffic noise impacts. In addition, it
is also recommended wherever possible to reduce traffic noise impacts in
planned areas through careful building layout/ designs.
With the implementation of all the
recommended mitigation measures, exceedance of the relevant noise limit was
still predicted at some schools due to noise from ‘new’ roads. Since all the available direct mitigation
measures have been exhausted, the affected schools would be provided with
indirect technical remedies to reduce noise such as air-conditioning and
appropriately glazed windows, which are the standard measures provided by Arch
SD according to Class Assessment Document.
The predicted unmitigated noise levels
at the NSRs in the vicinity of the proposed pumping stations and ventilation
buildings, except Eastern Ventilation Building would comply with the EIAO-TM
criterion. With the implementation of
acoustic silencers for reversible fans at Eastern Ventilation Building, the
closest NSRs would comply with the noise criteria.
Monitoring of noise is considered
necessary to verify the effectiveness of the mitigation scheme. It is recommended that traffic noise
monitoring should be carried out at the representative NSRs during the first
year after road opening. Noise monitoring should also be carried out during the
commissioning stage of the Eastern Ventilation Building.
Short-term water quality impact could
be associated with the proposed construction works. Impacts may result from the
surface runoff from construction sites, sewage from on-site construction
workers, wastewater from general construction activities, dredging and filling
operations and Deep Cement Mixing (DCM) treatment. Impacts could be controlled to comply with relevant
standards in the Water
Pollution Control Ordinance (WPCO) by implementing
the recommended mitigation measures. Therefore, unacceptable residual impacts on water quality are not
expected. Monitoring of water quality
is recommended to verify the effectiveness of the mitigation measures.
Water quality modelling results
indicated that the proposed WCR reclamation and construction of the CBL bridge
would not cause any adverse impact on the marine water quality in Junk Bay and
Victoria Harbour, taking into account the cumulative effect of all pollution
sources including those from landfill sites, non-point source surface run-off
and sewage from cross connections.
To minimise potential impacts on the
proposed beneficial use of Eastern Drainage Channel (EDC) for recreation
activities, drainage diversion work is proposed under this Project to divert
two existing storm outfalls from the EDC to the south of TKO town centre to
enhance the dispersion of pollutants. Modelling
results indicated that EDC and Junk Bay water quality would generally be
acceptable for secondary contact recreation with the recommended drainage
diversion. Monitoring of water quality is recommended to verify the model
Water recreation activity in the area of
the EDC and Junk Bay could be affected by the emergency release of sewage at the
seawall, but impacts are expected to be short-term. The occurrence of such an event is considered to be very remote. Nevertheless, should it occur, the plant
operators of Tsueng Kwan O Preliminary Treatment Works (TKOPTW) should closely
communicate with EPD and LCSD to ensure appropriate actions can be undertaken
to close the EDC and Junk Bay for water recreation activities. Water quality
monitoring is recommended at such a time to determine when conditions are
suitable for re-opening of the EDC and Junk Bay for recreational purposes. No
insurmountable water quality impact on the proposed beneficial use is expected
from any temporary discharges under emergency situation.
The performance of the existing and
committed sewerage infrastructure under full development condition for the
ultimate scenario of TKO was assessed.
The results indicate that there would be no risks of sewage overflow
under various peak flow conditions for the ultimate scenario. Based on the Environmental and Engineering Feasibility Assessment
Studies in Relation to the Way Forward of the Harbour Area Treatment Scheme, the TKOPTW and the Harbour Area Treatment Scheme (HATS) Stage I
Tunnel section from TKO to Kwun Tong are considered to be adequate to handle
the ultimate catchment flows. The
Project would not pose any capacity constraint on HATS, as there would be an
overall reduction in ultimate population and flows as a consequence of planned
A literature review and 6-month
ecological surveys covering the wet season were undertaken to establish the
ecological profile of the Assessment Area. As much of the proposed development
area is dominated by highly disturbed urban districts, terrestrial ecological
impact assessment was focussed on three areas where direct/indirect impacts to
terrestrial ecological sensitive receivers were anticipated.
The Assessment Areas were found to be
dominated largely by relatively low ecological value habitats, including areas
of wasteland and developed areas. Habitats considered of conservation interest
included moderate-high ecological value secondary woodland in the PSK
Assessment Area, and moderate ecological value stream habitats in the WCR in
TKO Area (E-WCR) and PSK Assessment Areas.
Four plant species of conservation
interest were recorded from the Assessment Areas during recent surveys.
Although the recorded species are all relatively common in Hong Kong, they are
either protected through Hong Kong or mainland Chinese Legislation, or are
considered to have regionally or globally threatened populations.
Several faunal species of conservation
interest were recorded in the Assessment Areas, comprising one fish, two
reptile, two mammal, one freshwater invertebrate, and 13 bird species. Of
particular interest was the fish species Philippine Neon Goby (Stiphodon
artopurpureus), recorded from a small stream below the Junk Bay Permanent
Chinese Cemetery. Previous records of the Eurasian Eagle Owl (Bubo bubo),
which is of regional conservation interest, have also been made from the E-WCR
Assessment Area. Although not recorded during recent surveys, it is possible
this species still occurs in the Assessment Area.
Direct terrestrial ecological impacts
resulting from developments proposed under this Project would generally be
confined to small areas of relatively low ecological value habitats. No direct
impacts to moderate-high ecological value secondary woodland or moderate
ecological value streams are expected. Habitat loss resulting from the proposed
works is expected to result in minor and acceptable ecological impacts.
Individuals of two of the plant
Persimmon (Diospyros vaccinioides) and Bamboo Orchid (Arundina chinensis)) of conservation interest would be directly
impacted by works proposed under this Project. It is recommended that the
plants be transplanted to suitable nearby habitats outside of the proposed
works areas prior to the construction phase.
Impacts to the majority of faunal
species of conservation interest recorded in the Assessment Areas are expected
to be relatively minor in scale. Many of the recorded species are often found
in urban/developed areas, and are not considered particularly sensitive to
disturbance (e.g., Black Kite, Milvus lineatus). Other species (e.g.,
Besra, Accipiter trivirgatus) were recorded at some distance from the
proposed works areas, and therefore would not be affected by construction or
operation phase activities. Records of some species (e.g., Black-naped Oriole, Oriolus
chinensis) refer to occasional sightings of migrant birds that would not be
substantially affected by the proposed works.
Without mitigation, substantial
impacts to the Philippine Neon Goby population recorded from the E-WCR Stream
have been predicted. Although no direct impacts to the stream habitat are
expected, reclamation works for the WCR within Junk Bay would result in the
loss/disturbance of habitats potentially utilised by juvenile Neon Gobies.
Measures to protect adult fishes during the construction phase and to provide
suitable passage from the stream to marine habitats during the operation phase
have therefore been recommended.
Measures to avoid, minimise and
compensate for various identified ecological impacts have been recommended.
With the implementation of the recommended mitigation measures, residual
terrestrial ecological impacts resulting from developments proposed under this
Project are expected to be ecologically acceptable.
Literature review of existing marine
ecological conditions was supplemented by field surveys of marine ecological
resources in the Assessment Area.
Surveys were conducted over a 6 month period from May to October
2004. Marine habitats affected by WCR
reclamation and construction of CBL were generally of low ecological
value. Rocky and sandy shore habitats
were considered to be of low-medium ecological value. Artificial seawall was
rated as being of very low ecological value. Soft substrata subtidal habitat at
Junk Bay was considered to be of low ecological value. Owing to the sparse cover of common hard
corals and patchy cover of soft and gorgonian corals, the Chui Keng Wan coast
at the proposed reclamation area was considered to be of low ecological value.
WCR reclamation would cause direct and
permanent loss of 1km of natural rocky shore and 0.2km of sandy shore. A total
of 16.5ha of subtidal habitat would be permanently lost mainly due to the WCR
reclamation area (16.3ha) but also due to construction of piers for the CBL
(0.2ha). Impacts to marine habitats (and natural shorelines in particular) have
been avoided and minimised as far as practicable taking into account
engineering constraints and also constraints posed by other environmental
considerations (e.g., the visual impact of the WCR reclamation). Direct impacts
to these habitats therefore would be largely mitigated for through the
compensation provided by construction of a sloping rubble mound seawall: the
seawall would provide a suitable habitat for rocky inter-tidal and coral
community re-colonisation. Owing to construction methods, dredging would be
relatively small scale and be conducted for approximately 1 month. The predicted results from water quality
modelling showed that relevant water quality objectives for suspended sediments
and dissolved oxygen concentrations would be complied with. With the implementation of recommended water quality and marine
ecological mitigation measures, indirect impacts on
adjacent hard substrata subtidal habitat, which supported sparse hard coral,
and some soft and gorgonian corals, were therefore predicted to be low.
The marine ecological impact
assessment determined that Junk Bay was not a key habitat for marine mammals,
with the nearest sighting
of a live Finless Porpoise (Neophocaena phocanoides)
to Junk Bay about 2km to the south of Tung Lung Chau. No substantial impacts to
marine mammals through increased marine traffic, noise disturbance or water
quality impacts are expected.
In summary, residual marine ecological
impacts resulting from the Project were assessed as being minor and acceptable.
A literature review has been conducted
to incorporate the latest relevant information for determining impacts on
fisheries arising from the Project.
The size of catches in the Junk Bay
Assessment Area was ranked as low to moderate compared to other fishing grounds
in Hong Kong, and the fish species captured were considered to be of low
commercial value. Fishing grounds in
Inner Junk Bay were considered to be of low commercial importance. The only sensitive fisheries receiver
identified in the vicinity of the project is the Fish Culture Zone at Tung Lung
The proposed WCR reclamation and CBL
construction would result in the direct loss of approximately 16.5 ha of potential
fishing ground at Inner Junk Bay. The
loss of this area is anticipated to have little effect on fisheries production
of Hong Kong as a whole.
Provided that all the mitigation
measures recommended in the EIA for protection of the water quality are fully
implemented, specific mitigation measures to protect fisheries resources would
not be necessary. Similarly, audit
activities on work sites to ensure prevention of water quality impact would
also serve to protect fisheries resources.
Therefore, a specific EM&A programme for fisheries is not
In terms of Annex 10 of the EIAO-TM,
the landscape and visual impacts are considered to be acceptable with
mitigation measures. While the residual
impact on the landscape resources (the natural coastline and topography along
the western side of Junk Bay and inner Junk Bay as well as the Character Area
of inner Junk Bay) will remain substantial, the current design of the Project has
already minimised the amount of reclamation as far as practicable and also ensures
that other valued resources including areas of coral further along the coast would
not be disturbed.
The dredged volume for the WCR Phase 1
reclamation was estimated to be approximately 20,000 m3. With the implementation of the recommended
mitigation measures and management procedures in accordance with the
requirements of ETWB TCW No. 34/2002, no residual impact was predicted.
Other waste types generated by the
construction activities are likely to include construction and demolition
(C&D) material (from foundation, excavation and tunnelling works), general
refuse from the workforce and chemical wastes from the maintenance of construction
plant and equipment. Provided that
these identified waste arisings are to be handled, transported and disposed of
using approved methods and that the recommended good site practices are to be
strictly followed, adverse environmental impacts would not be expected. During the operation phase, domestic waste
would be generated by the planned residential use at the new development areas
at PSK, TCS and TKL. Domestic waste generated
in the development areas would be directed to the SENT Landfill.
The calculations show that, assuming
75% biodegradable Total Organic Carbon (which is a worst-case scenario) the
estimated methane emission from the WCR reclamation is estimated to be well
below all relevant assessment criteria.
It is therefore concluded that the methane gas generation potential is
not expected to pose a development constraint to the proposed WCR reclamation.
Furthermore, the planned land use of
highway and toll plaza on the proposed WCR reclamation is not sensitive to
potential biogas emission. The proposed
administration building of the toll plaza would not have a basement and
therefore potential biogas emissions would be considered to pose a very
limited, if any, risk.
Based on the baseline review of marine
archaeology and the marine geophysical survey results, a surface anomaly having
archaeological potential was identified.
This surface anomaly is located close to one of the proposed piers of
the CBL and could be directly impacted.
A visual diver survey should be carried out during the detailed design
stage of the Project. The dive survey
should cover the surface anomaly and also the position of the area to be
reclaimed that was not covered by the marine geophysical survey.
No pre-war clan or notable feng shui
features such as feng shui woods and ponds or historical trackway or other
historic features were identified within the Study Area. All of the fourteen identified notable
buildings and structures are located outside the Project boundary, so direct
impacts are not expected. Nevertheless,
since Cha Kwo Ling Tin Hau Temple is located less than 50m from the works area
of the proposed roundabout at Cha Kwo Ling, it may be indirectly impacted by
dust and vibration due to the nearby construction activities of the Project. To prevent damage to Cha Kwo Ling Tin Hau
temple during the construction phase, a temporarily fenced-off buffer zone
(with allowance for public access) should be provided around the temple. Monitoring should be carried out at the
temple during the construction period.
The results of the qualitative risk
assessment of landfill gas hazard posed by TKO Stage I & II/III Landfill
and Sai Tso Wan Landfill to the proposed project site suggested that the
overall level of the landfill gas hazard would be medium for the three areas.
Some appropriate protection measures
have been proposed to minimise the landfill gas hazard for the proposed project
site during the construction phase and operational phase. These measures should be implemented as
appropriate during the construction phase and/or operational phase of the
Provided that the recommended
protection measures are implemented properly, the health and safety of the site
workers/ personnel working at the proposed project site would be safeguarded
and there would be no adverse impact on the proposed project.
The hazard to life from the proposed
Dangerous Goods Vehicles Ferry Pier (DGVFP) that could result from modification
of the access road to the vehicle queuing area (due to the two WCR slip roads
proposed under this Study) was assessed.
In the assessment, three changes
introduced by the two proposed slip roads to the surrounding environment of the
proposed DGVFP were noted but the changes would not induce significant change
to the risk levels associated with the proposed DGVFP due to the following
conditions: (1) the
existing nature (presence of ignition sources with high presence factor) of
locations near the proposed DGVFP, (2) an insignificant increase of total
population arising from the proposed slip roads when compared to that
considered in the Previous Assessment. Moreover,
as assessed in the Previous Assessment, there is a comfortable margin between
the estimated risk level and the upper boundary of acceptable region for
societal risk. Therefore, it is
considered unlikely that the risk guidelines would be breached due to the
changes introduced by the two proposed slip roads. This shows that the Project is unlikely to be infeasible in terms
of hazard to life implication.
Moreover, the scenario considered in
the current Study (relocation of the existing DGVFP to Cha Kwo Ling, near Slip
Roads S1 and S2) is based on the assumption that the sea area near the Kai Tak
Airport Runway is reclaimed. Also, the
Trunk Road T2 and DGVFP are subject to review under the South East Kowloon Development
(SEKD) Comprehensive Planning and Engineering Review by Planning
Department. A Quantitative Risk
Assessment should be carried out by the project proponent of SEKD to confirm
the compliance of risk guidelines, if it is proposed that the existing DGVFP is
to be relocated.
Environmental monitoring and audit
(EM&A) requirements have been specified in an EM&A Manual. The EM&A Manual contains full details of
proposed baseline and compliance monitoring programmes, as well as performance
specifications, audit requirements and monitoring procedures.