11.
CONCLUSIONS AND RECOMMENDATIONS
Introduction
11.1
This EIA Report has provided an
assessment of the potential environmental impacts associated with the
construction and operation of the development on the proposed CPR improvement
works according to the latest information available. The Implementation
Schedules of the recommendations are presented in Section 12. The principal findings of this Report are
summarised in the following sections.
Air Quality Impact
Construction Phase
11.3
To further ensure compliance with the
guideline level and AQO limit at the ASRs at all times, the implementation of
the Air Pollution Control (Construction
Dust) Regulation and the inclusion of good site practice in the contract
clauses to minimize cumulative dust impact are also recommended. In addition, a comprehensive dust monitoring
and audit programme is recommended to ensure proper implementation of
mitigation measures. Details of the
monitoring and audit requirements are provided in a separate EM&A Manual.
Operation Phase
11.4
The dispersion of nitrogen dioxide (NO2),
respirable suspended particulates (RSP) and carbon monoxide (CO) arising from
the background pollutant levels within and adjacent to the proposed CPR,
vehicle emissions from open road networks, portal emissions from the full
enclosures recommended for the proposed CPR and the full enclosure at the Route
10 NLYLH’s Siu Lam Link Roads (SLLR) were modelled. The results indicate that the AQO would be satisfied at all
existing and planned ASRs. No adverse
cumulative air quality impact is predicted.
Therefore, no mitigation measures are required.
11.5
The air quality inside the full
enclosures recommended for the proposed CPR was also calculated. The results indicate that no exceedance of
the Tunnel Air Quality Guideline is expected and therefore no mitigation
measures are required.
Noise Impact
Construction Phase
11.6
Unmitigated cumulative noise levels
arising from the construction activities of the project at the representative
noise sensitive receivers (NSRs) have been predicted. The results indicate that without any mitigation, the cumulative
noise levels at most of the NSRs would exceed the EIAO-TM noise criteria.
11.7
In order to alleviate the construction
noise impacts at the NSRs, noise mitigation measures are recommended including
adoption of good site practice, the use of quiet plant, movable noise barriers
and restriction on the usage of operating plant.
11.8
With the adoption of the recommended
control measures, all the residential NSRs could be effectively protected
against the construction noise impact.
For the educational NSRs, the use of the recommended direct mitigation
measures would protect them from exceedance of the noise criterion for schools
during normal hours, but these measures would be insufficient to protect them
from exceedance of the noise criterion for school during examination period
(which is 5dB(A) lower). In order to
reduce the potential noise impacts on the schools, re-scheduling of
construction activities to avoid concurrent operations are required during the
examination period.
Operational Phase
11.9
Potential road traffic noise impact
associated with the project has been assessed for the maximum traffic flows
expected to occur in 2022. About 170
residential dwellings and 25 classrooms are predicted to experience noise
levels, if unmitigated, exceeding the traffic noise criteria. Hence direct mitigation measures would be
required.
11.10
With the implementation of the
recommended direct mitigation measures, the mitigated noise levels from new
roads at all the representative NSRs are predicted to be below 70dB(A) and the
contribution from new roads to the overall noise levels would be less than
1dB(A). It is estimated that about 30
residential dwellings would benefit by more than 1dB(A).
11.11
The residual impacts have been
assessed against the noise insulation criteria. The results show that no residential dwellings, schools or
hospitals would meet the noise insulation criteria and therefore, indirect
technical remedies in the form of window insulation and air conditioning would
not be required.
Water Quality Impact
Construction Phase
11.12 The potential water quality impacts associated with the dredging
activities during the construction of the reclamation and seawalls have been
assessed by predicting the increases in suspended sediment concentrations due
to fine sediment lost to suspension.
11.13 There are no sensitive receivers identified within the Study
Area. The nearest receivers include Ma
Wan Fish Cultural Zone (FCZ), fish nursery areas in bays on north Lantau to the
west of Kap Shui Mun Channel, Golden Beach and Anglers’ Beach, which are all
located outside the Study Area and are far away from the works area of the
project. It is anticipated that the
unmitigated elevations in suspended sediment (SS) concentration generated from
the dredging activities of the project at these sensitive receivers would not
exceed the allowable elevations in SS concentrations. However, the cumulative elevated SS concentrations from the
proposed project and the identified concurrent projects are predicted to exceed
the allowable elevated SS concentration at the Ma Wan FCZ. The use of closed grab dredgers and silt
curtains is therefore recommended to minimize the water quality impact from the
dredging works for the project.
11.14 With the use of closed grab dredgers and silt curtains, the dredging
works of the proposed project would not contribute significantly to the total
SS concentrations at the Ma Wan FCZ (less than 3%). Further constraints on the dredging activities of the proposed
project could not further reduce the predicted cumulative impact and therefore
it would be the responsibility of the concurrent projects to apply mitigation
measures should unacceptable water quality impacts be detected during
construction.
11.15 The potential impact arising from the release of contaminants from
sediment disturbed during the dredging works has also been assessed. It was predicted that because of the general
absence of significant sediment contamination in the dredging area, adverse
water quality impacts arising from the release of heavy metals, nutrients and
organic compounds are not expected during the dredging works.
11.16
With the adoption of the recommended
mitigation measures, no unacceptable residual impacts on water quality impact
are expected.
Waste Management Implications
11.17 A review of the sediment quality data from the marine ground
investigation works indicated that the majority of the marine sediments in the
proposed dredging area for the Tai Lam Kok reclamation and new seawall from Tai
Lam Kok to Ka Loon Tsuen are classified as category L. This dredged sediment will therefore be
suitable for open sea disposal. The
small volume of sediment classified as Category H at the Tai Lam Kok
reclamation will require confined marine disposal.
11.18 An assessment of the potential environmental impacts of waste
arising from the construction of the project has been conducted. Wastes generated by the construction
activities are likely to include construction and demolition (C&D)
materials, general refuse and chemical waste.
Provided that these identified wastes are handled, transported and
disposed of using approved methods and that the recommended good site practice
is adhered to, adverse environmental impacts are not expected.
Ecological Impact
Terrestrial Ecology
11.19 The ecological resources within the study area comprise a variety of
habitat types including woodland, tall shrubland, grassland/shrubland mosaic,
backshore vegetation, mudflat, village/orchard, developed area,
active/abandoned farmland, wasteland, plantation, fishpond and Tai Lam Chung
River. Grassland/shrubland mosaic was
found to support three rare/protected plant species: Alloteropsis semialatus, Platycodon grandiflorus and Thysanotus chinensis. All these
rare/protected plant species are located outside the construction
boundary. No direct impact to the
rare/protected plant species due to construction is anticipated.
11.20 The road improvement works will result in the permanent loss of
approximately 2 ha of backshore vegetation, 0.2 ha of wasteland, 0.4 ha of
plantation and 0.1 ha of tall shrubland.
All these habitats are of low ecological value and therefore adverse
impact to the terrestrial ecology is not anticipated. With the implementation of the recommended mitigation measures,
no adverse residual impact is expected.
Marine Ecology
11.21 Literature reviews of existing information supplemented with the
results of recently undertaken field surveys on marine ecological resources
indicate that the intertidal habitats and soft benthic habitats within the
study area are of low ecological value.
11.22 The dredging / reclamation and the road improvement works will result
in the permanent loss of approximately 14,348 m2 of soft bottom
benthic habitat and approximately 1.1 km of artificial intertidal habitat. Since the benthic community and intertidal
community in the study area are of low ecological value and rubble-mound
seawall will replace much of the lost intertidal habitat, no adverse impact is
anticipated.
Fisheries Impact
11.23 Fisheries resources sensitive to the project have been
identified. In terms of fish
production, the fishing areas concerned contribute a small proportion to the
territory’s total thus the overall fisheries impacts are predicted to be
minimal. No specific mitigation measure is necessary as no adverse impact is
identified.
Landscape and Visual Impacts
11.24
The major findings of the LVIA are as
follows:
·
The majority of the baseline condition of the study area is considered
to be of local importance, with the exception of a small part of the study area
in the Tai Lam Country Park which is of regional importance.
·
No areas designated with a landscape zoning such as country park, open
space or green belt would be affected by the Project and therefore the Project
is compatible with the Government’s statutory planning framework in terms of
landscape conservation.
·
The Project would result in the loss of approximately 2.0ha of coastal
vegetation, 0.5ha of roadside vegetation and affects 1.6ha of open sea under
viaducts. Compensatory planting will
provide 2.63ha of roadside and amenity planting, resulting in a net gain of
0.13ha of trees and shrubs.
·
The introduction of the Project into the study area will result mainly
in moderately adverse to slightly beneficial landscape impacts assuming
mitigation measures are incorporated into the scheme. The moderately adverse landscape impact will occur along the Ma
Wan coastal area, while there will be a slightly beneficial landscape impact
along the Tuen Mun Road corridor.
·
The introduction of the Project into the study area will result mainly
in moderately adverse visual impacts assuming mitigation measures are
incorporated into the scheme. The incorporation of visual mitigation measures
into the Project will reduce all of the moderate/significant visual impacts to
moderate levels.
·
The viewer group at SVR5 Siu Lam Police Quarters will experience
moderate/significant adverse levels of residual visual impact.
·
The proposed viaduct and the associated noise barriers and enclosures
will continue to give long term significant adverse visual impact.
·
The significance of the proposals in visual terms is changed considerably
with the construction of the Route 10 Link Roads should they proceed. The
baseline condition will be changed to a point where the visual implications
become far less significant in terms of magnitude of change. However the
cumulative impact of the two projects together will be significantly more
adverse.
Overall Conclusion
11.25
The findings of this EIA have provided
information on the nature and extent of environmental impacts arising from the
construction and operation of the project.
The EIA has, where appropriate, identified mitigation measures to ensure
compliance with environmental legislation and standards.
11.26 Overall, the EIA Report for the proposed CPR improvement works has
predicted that the project will comply with all environmental standards and
legislation with the implementation of the proposed mitigation measures for
construction and operation phases. This
EIA has also demonstrated the acceptability of the residual impacts from the
project and the protection of the population and environmentally sensitive
resources. Environmental monitoring and
audit programmes have been recommended, where necessary, to verify the accuracy
of the EIA predictions and the effectiveness of recommended mitigation measures.