At present, traffic
queues are already observed on the northern approach of Pok
Oi Roundabout (POR) during the evening peak period, and the southern approach during both morning and
evening peak hours. The situation
will likely deteriorate further when nearby developments are completed. The tailback of traffic onto the
southbound carriageway on the northern approach to POR may block the through
traffic from Tai Lam Tunnel / New Territories (NT) North to Tuen
Mun / Tin Shui Wai /
ERM-Hong Kong, Ltd (ERM), supported by Halcrow China Ltd (Halcrow), has
been commissioned by the Highways Department (HyD) to
undertake the Improvement to Pok Oi Interchange –
Environmental Impact Assessment Study (“the Assignment”) under Agreement
No. WD 6/2007. As part of the
Assignment, an Environmental Impact Assessment (EIA) Study has been prepared in
accordance with the EIA Study Brief
(No. ESB-166/2007) issued
under the Environmental Impact Assessment
Ordinance (EIAO).
The EIA Report
addresses potential environmental impacts associated with the construction and
operation of the Improvement to Pok Oi Interchange (“the Project”). This Executive
Summary summarises the key findings of the EIA.
1.2
Objectives of and
Approach to the EIA Study
The objectives of the EIA Study are to
provide information on the nature and extent of environmental impacts arising
from the Project; to recommend appropriate mitigation measures to control the
potential environmental impacts so that it complies with the requirements of
the Technical Memorandum on Environmental
Impact Assessment Process of the EIAO (EIAO-TM); and to confirm the
environmental acceptability of the Project. Key environmental issues identified in
the EIA Study Brief include air
quality, noise, water quality, waste management, and landscape and visual
impacts.
The EIA was conducted in accordance with
the guidelines on assessment methodologies provided in the EIAO-TM. The general
approach for the assessment includes description of baseline environmental
conditions for the impact assessment, identification and evaluation of
potential impacts and recommendation of mitigation measures and an
environmental monitoring and audit programme. The assessments in this EIA Study are
conducted using well-proven and internationally accepted methods based on
reasonable worst-case conditions.
Alternative construction methods and
sequences of works have been considered and environmentally friendly
construction methods have been adopted to avoid / minimise impacts to the
surrounding sensitive receivers, where appropriate and practicable.
The proposed alignment of the Project is
shown in Figure
2.1a. The scope of the
Project is as follows:
·
provision
of a single lane flyover (approximately 140m in length) adjacent to the
northbound carriageway of Pok Oi
Flyover (POF) (denoted as Flyover A in Figure 2.1a and subsequent sections of this
report);
·
construction
of a slip road (approximately 410m in length) connecting the northbound
carriageway of the ground level road of Yuen Long Highway (YLH) on the southern
arm of POR to the proposed flyover (denoted as Slip Road A in Figure 2.1a
and subsequent sections of this report);
·
construction
of a slip road (approximately 100m in length) connecting the proposed flyover
to the northbound carriageway of the ground level section of YLH on the
northern arm of POR (denoted as Slip Road B in Figure 2.1a and subsequent
sections of this report);
·
construction
of a slip road (approximately 280m in length) connecting the southbound carriageway
of POF to the southbound carriageway of the ground level section of YLH on the
southern arm of POR (denoted as Slip Road C in Figure 2.1a and subsequent
sections of this report);
·
resurfacing
and re-marking of a stretch of the southbound carriageway (approximately 280m
in length) of the ground level section of YLH on the northern arm of POR to
increase the number of traffic lanes on the carriageway from three to four
(denoted as Road Resurfacing and Remarking A in Figure 2.1a and subsequent
sections of this report);
·
resurfacing
and re-marking of a stretch of the northbound carriageway (approximately 470m
in length) of the ground level section of YLH on the northern arm of POR (denoted
as Road Resurfacing and Remarking B in Figure 2.1a and subsequent sections of this
report);
·
construction
of a segregated left-turn lane (approximately 110m in length) at the northern
arm of POR (denoted as
·
associated ancillary works.
The construction of the Project is
scheduled to commence in December 2009 and to be completed in December 2011.
The potential environmental impacts
associated with the Project are summarised in the following sections.
Potential dust nuisance from construction activities
and gaseous emissions from diesel-powered construction plant have been
considered. With the implementation
of the recommended dust control measures and adoption of good construction site
practices, adverse dust and air quality impacts from the construction of the
Project are not anticipated.
Upon completion of
the Project, vehicular emissions from the open roads would be the potential
source of air quality impact. The
key air pollutants from vehicular emissions include Nitrogen Dioxide (NO2)
and Respirable Suspended Particulates (RSP). A quantitative assessment has been
conducted using the peak hourly traffic flow of the proposed new roads and the
surrounding road network and fleet emission factors estimated using the
EMFAC-HK model. The prediction
indicated no exceedance of hourly and daily average
concentrations of NO2 or daily average concentrations of RSP in the
vicinity of the Project.
It must be emphasised that the objective of the Project is only to
relieve the traffic pressure and traffic queues of the existing POR and the
design traffic flow / capacity ratio will be maintained. There will not be any increase in the
overall traffic flow as a result of this Project.
The vehicular
emissions associated with road traffic with the implementation of the Project
are expected to comply with the respective AQOs, and
therefore will not cause an adverse air quality impact.
Regular site audits are recommended to
ensure the implementation of recommended dust control measures and adoption of
good site practices during construction.
Potential
construction noise impacts will mainly be due to road works, construction of
flyover, construction of retaining walls, abutments
and embankments. During normal daytime working hours, the
predicted noise levels at some of the representative noise sensitive receivers
(NSRs), including the Jockey Club Care & Attention Home,
The potential road traffic noise impacts
have been assessed based on the Year 2026 traffic forecast, which is the
maximum projected traffic level.
With the provision of a 2.5 m high vertical noise barrier for the
planned school, no adverse noise impacts are
predicted at the NSRs during the operational phase of
the Project. In the design
year for the Project, the traffic noise levels for the case with the Project in
operation will not be significantly higher, ie by 1.0
dB(A) or more, than those for the case without the
Project. Based on the above, the
traffic noise impact due to the Project is considered insignificant. Furthermore, the mitigated noise levels
due to the road sections within the meaning of Item A.1 of Schedule 2 under the
EIAO complied with the noise criteria
as stipulated in the EIAO-TM.
Monitoring of construction noise and road
traffic noise is recommended to verify the effectiveness of the mitigation
scheme during the construction period and during the first year after the
commencement of operation.
Potential sources of water quality impact
associated with the Project include Site runoff, discharges from construction
activities and sewage effluents from the on-site workforce. Water quality impacts from the
land-based construction works can be controlled to acceptable levels by
implementing the recommended mitigation measures. All the effluents and runoff generated
from the Site will be treated to relevant standards stipulated in the Technical Memorandum - Standards For
Effluents Discharged Into Drainage And Sewerage Systems, Inland And Coastal
Waters issued under Water Pollution
Control Ordinance (WPCO-TM)
before discharge. No unacceptable
water quality impact is expected from the land-based construction activities
with the adoption of appropriate drainage management and mitigation
measures. Regular site inspections
are recommended to ensure that the recommended mitigation measures are properly
implemented.
For the operational phase, a road drainage
system with appropriate silt or grit traps will be provided to collect runoff
from the road surface during periods of rain. With the provision of an appropriate
road drainage system, no adverse water quality impacts are anticipated. No operational water quality monitoring
is considered necessary.
Wastes generated by the construction
activities are likely to include construction and demolition (C&D)
materials from the construction works, general refuse from the workforce and
chemical waste from any maintenance of construction plant and equipment. Provided that these identified waste arisings are handled, transported and disposed of using
approved methods and that the recommended good site practices are strictly followed,
adverse environmental impacts are not anticipated during the construction
works.
The potential land contamination impacts
within the Study Area have been examined.
Based on the findings from the desktop studies and site inspection, no
contaminated sites were identified within the vicinity of the Project
boundary.
3.5
Landscape and
Visual Impact
Three
Landscape Character Areas (LCAs), LCA1 Miscellaneous Rural Fringe Landscape, LCA2
Miscellaneous Urban Fringe Landscape, and LCA3 Urban Peripheral Village Landscapes,
were identified. The
residual impacts on all three LCAs will be negligible.
A
total of seven Landscape Resources (LRs), LR1 Roads,
LR2 Agricultural Land, LR3 Roadside Plantation, LR4 Developed Area, LR5
Disturbed Area, LR6 Nullah and LR7 Village, were
identified. LR3 Roadside Plantation
will experience moderate adverse and slight adverse residual impacts during
construction and operation respectively.
However, there will be negligible
residual impacts on all other Landscape Resources.
Four Visually Sensitive Receivers (VSRs) , VSR1 Sun Yuen Long Centre,
VSR2 Pok Oi Hospital, VSR3 Kwong Ming Ying Loi School and
VSR4 Yeung Uk Tsuen, were identified. There will be negligible residual
impacts (impact at year 10) on all four VSRs.
According to Annex 10 of the EIAO-TM, the landscape and visual
impacts are considered acceptable with
mitigation.
3.6
Environmental Monitoring and Audit
Environmental monitoring and audit
(EM&A) requirements have been identified and recommended to ensure the
effectiveness of the recommended mitigation measures. These requirements are outlined in the
EIA Report. Monitoring of
construction noise and operational road traffic noise is recommended to check
compliance with relevant statutory criteria and to ensure the effectiveness of
the mitigation measures. Site
inspection and audit are also recommended to ensure that the recommended
mitigation measures are in place and operating effectively during construction.
The environmental impact assessment has
concluded that the construction and operation of the Project will not cause any
unacceptable environmental impacts, provided that the recommended mitigation
measures are implemented.
To ensure the effectiveness and proper
implementation of the recommended mitigation measures, an EM&A programme
has also been recommended.