Reprovisioning
of FEHD Sai Yee Street Environmental Hygiene Offices-cum-vehicle Depot at Yen
Ming Road, West Kowloon Reclamation Area
Environmental Impact Assessment Report
Executive Summary
CONTENTS
2.3 Selection of Project Scheme
2.5 Project Implementation Programme
3. Key Findings of Environmental Impact Assessment
3.3 Water Quality and Sewage Impact
3.4 Waste Manamgenet Implications and Land
Contamination
3.5 Landscape and Visual Impact
4. Environmental Monitoring and Audit
List of Figures
1.1.1
The existing Sai Yee Street
Vehicle Depot in Mong Kok of Food and Environmental Hygiene Department (FEHD)
has to be demolished as the land is scheduled to be returned to Lands
Department by March 2017. Continuation of
the vehicle repairing and maintenance services of the existing Sai Yee Street
Vehicle Depot as well as the washing service of the new depot is crucial to
ensure the vehicles are clean, hygienic and under normal and safe operation in
the FEHD fleet of West Kowloon region including Sham Shui Po, Mongkok, Yau Ma
Tei and Tsim Sha Tsui districts. FEHD
therefore requires
a land piece for housing the existing facilities in Sai Yee
Street Vehicle Depot.
1.1.2
This Project is to
construct and operate a new offices-cum-vehicle depot building (the Depot) at Yen Ming Road, West Kowloon to accommodate the existing facilities in Sai Yee Street Vehicle Depot and to carry
out vehicle washing and repairing services for the FEHD fleet in the district and their parking when they are not in operation.
2.1.1
The
Project is located on an urbanised area at Yen
Ming Road (the Site),
which is a land piece zoned as “Government,
Institution or Community” use in the Outlined Zoning Plan No. S/K20/28, whilst
commercial, residential and institutional uses are located in the proximity. The Site constitutes an area of previously developed reclaimed land
which was recently occupied by Civil Engineering and Development Department
(CEDD) as site offices and associated storage (just returned). The location of the Site with an area of about 8,278m2 is
shown in Figure 2-1.
2.1.2
The Depot will be a
five-storey building comprising various facilities for vehicle washing and
repair operation, parking of vehicles as well as offices. The lowest three floors will provide
vehicle maintenance and vehicle washing facilities for carrying out general
vehicle repair and washing activities as well as providing parking spaces for
the FEHD vehicle fleet of West Kowloon region.
Offices and stores will be mainly located on the higher floors, with
green roof design providing substantial landscape features.
2.2.1
In accordance with Item A.6, Part I, Schedule 2 of Environmental Impact Assessment (EIA) Ordinance, this Project is a
designated project under the category of “A transport depot located less than 200m from the nearest boundary of
an existing or planned residential area / educational institution”. An EIA is required and an Environmental Permit
(EP) is to be obtained prior to construction commencement. An application for the EIA Study Brief under Section 5(1) of the
EIA Ordinance (EIAO) was submitted by the FEHD on 17 April 2012 with a Project
Profile (No. PP-463/2012). The EIA Study Brief (No. ESB-245/2012) was issued by the Environmental Protection
Department (EPD) on 25 May 2012 to proceed with an EIA study for the
Project.
2.2.2
This EIA Report was
prepared in accordance with the abovementioned EIA Study Brief (No. ESB-245/2012). The purpose of this EIA study is to provide
information on the nature and extent of the potential environmental impacts arising from construction and operation of the
Project and associated works that will take
place concurrently.
2.3
Selection
of Project Scheme
Design of the Depot
2.3.1
The following designs were
considered and reviewed in order to optimise the operational and
environmental benefits of the facility:-
·
Building Design: To minimise the potential
environmental impacts, in particular on noise and air quality perspectives,
different forms of building have been considered and eventually non-open form
was preferred for vehicle repairing and washing activities, which are now to be
located at ground floor and refined and covered by floors above.
·
Building Layout: Layout design was investigated in
details in order to strike the balance between operational needs, as well as to
cater environmental considerations.
Activities with potential environmental implication / nuisance were
located in a confined manner as possible including covered vehicle repairing
bays and workshop surrounded by storerooms for noise screening as well as solid
partition wall to entirely isolate potential nuisance from the manual vehicle
washing bays. Substantial greenery features for enhancing visual quality were
also considered.
·
Mechanical Ventilation System: Mechanical
ventilation system is specially arranged for different functional areas. Car
parking areas provided with vast amount of openings would have rare usage of
associated substantial mechanical ventilation system to miminise potential
noise impact from fixed plant system. Whilst sufficient forced air changes
would be provided for activities with potential nuisance such as repairing
activities at the workshop and vehicle washing.
·
Local Exhaust: Ventilated exhaust will be treated
prior to discharging to the atmosphere.
Various gas treatments were evaluated and the most appropriate
technology with proven removal efficiency (e.g. activated carbon filter,
bio-oxygen generator) will be applied.
Location and orientation of the local exhaust were carefully examined to
ensure sufficient dispersion and to avoid direct impact to the nearby
receivers.
Construction
Methodology
2.3.2
Construction of the Depot would involve
various typical work stages and conventional building
services works. As such, consideration of
alternative construction method is focused on the
design of the foundation works. According to the ground condition of the
Site, two foundation types, namely driven steel-H piling (percussive) and bored
piling (non-percussive) as described below were
considered:-
·
Steel-H driven piling is a percussive piling
method. It has the supporting capacity
more suitable for low rise buildings and higher flexibility in the pile
arrangement, enabling higher load/capacity. Minimal waste is generated and
fewer plants (e.g. sedimentation tank, grouting machines) are required. The construction time required is relatively
short and hence the potential environmental impacts during the construction
phase, e.g. construction dust, noise, site effluent, C&D waste, etc would
be reduced. It is relatively the most cost effective pile system.
·
Bored piling is a non-percussive piling method with
high pile capacity suitable for medium to high rise buildings. Quality of pile can be controlled
effectively. Nevertheless, the construction time is long (especially in rock)
in comparison to other pile types. Also,
it needs to reach deep bedrock and with long pile length for end-bearing piles
in rock. It is relatively more expensive compared to driven-H piling.
2.3.3
Although relatively less noise and
vibration would be generated by bored piling during construction, the
excavation would be comparatively substantial and not cost effective when
compared to driven steel H-pile. Therefore, driven steel
H-pile would be selected for the proposed Depot.
2.4.1
Based on the above
considerations of alternatives, a preferred option has been selected in the
design phase of this Project is summarised below, based on which this EIA study
was carried out:
·
Optimum design for building design, facilities
layout, ventilation and local exhaust design; and
·
Optimum construction method using steel-H driven
piling.
2.4.2
This preferred option is
determined upon the comparison of the feasibility in line with the environmental
benefits and dis-benefits of the various options and alternatives. It was also selected on the principle of
minimising the environmental impacts and optimising overall environmental
benefits and acceptability over the other options.
2.5
Project
Implementation Programme
2.5.1
The construction works are planned to be
commenced in late 2014 and to be completed in late 2016/ early 2017, upon which mobilisation and
installation of the equipment will be carried out. The new building will then be handed over to
FEHD for operation.
2.6.1
The Project is to
reprovision the existing Sai Yee Street Vehicle Depot by another site, in order
to return the land at Sai Yee Street to Lands Department. A plan is noted proposing to redevelop the
site including commercial development above a public transport interchange
(PTI), as well as provision of public open space and preservation of the
existing mature trees at the site.
2.6.2
As such, the heavy traffic
flows and traffic jam suffered currently at Sai Yee Street would be
re-organised and resolved, which would relieve air quality in local extent from
traffic emissions.
2.6.3
Furthermore, as mentioned
above, public open space is to be developed, where landscaping areas would be
enhanced and thus favouring the landscape and visual quality in the area.
2.6.4
Moreover, the existing
depot was built and has been operating for a long period of time. Limited
comprehensive environmental measures could be incorporated into the design of
the existing depot due to technical and spatial constraints. This might impose certain concerns from the
neighbour (e.g. noise and odorous emission during vehicle repairing
works). With the Project to reprovision
the existing depot, the environmental nuisance to the surrounding at Sai Yee
Street site will be totally eliminated.
Meanwhile, with the adequately designed environmental protection
measures to be incorporated to the facilities as needed, particularly at the
odorous areas like washing bays and workshops to be arranged at enclosed
building envelop with sufficient negative ventilation and odour removal
equipment prior discharging the vent gas where the vent location and
orientation also examined, such nuisance will not be relocated / transferred to
the proposed new site.
2.6.5
Last but not the least,
extensive greening measures (pedestrian and roof levels, as well as facades)
would be incorporated into the new Depot, which could be beneficial to
landscaping and visual quality of the area, comparing with the CEDD’s site
offices and associated storage areas (just returned), and thus enhance the
living quality of the environment.
2.7.1
During the course of planning and
development of the Project, local public has been communicated and
liaised. In particular, meetings / forums
were held to consult the local residents, encouraging them to express views and
concerns.
2.7.2
Amongst different issues raised from the
local residents, environmental concerns were also expressed, such as potential
smelling issues from the activities, road vehicular noise and air emissions, as
well as the selection of traffic routing of the future vehicle fleets.
2.7.3
Once the said concerns were received and
well noted, the Project Team has examined various optimisations and design
enhancements for the Project to resolve the local’s comments, including the
provision of odour removal equipment and ventilation system, as well as traffic
re-routing of vehicle fleet away from the concerned road lanes and receivers,
in order to minimise nuisance to the locals.
2.7.4
The associated environmental nuisances
have been adequately assessed in the following chapters of the report to
address public concerns.
Construction Phase
3.1.1
There would be no major earthworks carried out for
the site formation works for the Site. Only minor excavation works
would be anticipated for the construction of the concrete footing for the
support of the sandwich roof and, also, the underground drainage and plumbing
works. Since the amount of construction
and demolition (C&D) materials generated would be minimal, impacts from the
transportation of dusty materials would be unlikely.
3.1.2
With the implementation of sufficient dust
suppression measures as stipulated under the Air Pollution Control
(Construction Dust) Regulation, adverse construction dust impact would not be
anticipated.
Operation Phase
3.1.3
Potential sources of air pollutant emissions would be from vehicular
movement and idling vehicles with their started engines within the Depot. Vehicular emissions from the surrounding open
roads would also be a dominant source of air pollutants to the Project. Air modelling was used to evaluate
concentration of major pollutants from vehicular exhaust, which are Nitrogen
Dioxide (NO2) and Respirable Suspended Particles (RSP), from the open roads within 500m study area.
3.1.4
The worst-case scenario determined based on the highest Nitrogen
Oxides (NOx) emission scenario using the EMFAC-HK is Year 2017. The highest 1-hour, 24-hour and annual
concentrations of NO2 are 137.98, 92.65 and 77.68 µg/m3 respectively. For RSP, the highest 24-hour and annual
concentrations are 57.27 and 53.29 µg/m3 respectively. The simulation indicated that the
concentration of NO2 and RSP are in compliance with Air Quality
Objectives.
3.1.5
Odour analysis conducted for the operation of the Project
revealed that potential odour emission and minimal spread in the
Depot would
be localised only in the washing bay. Mechanical ventilation adopting with proper
installation and maintenance of deodourisation system, as well as the dilution
along considerable buffer distance between the Depot and the
adjacent ASRs
will be provided.
3.1.6
Therefore, no adverse air quality impacts would be anticipated due to
limited vehicular emissions from the repairing and parking activities. Also, with implementation
of described engineering design, potential odour nuisance associated with
the operation of the Depot is anticipated to be negligible.
Construction Phase
3.2.1
The potential sources of noise impact during
the construction phase of the Project which would mainly be the use of Powered
Mechanical Equipment (PME) for various construction activities have been
assessed according to Technical Memoranda on Noise from Construction Work Other Than
Percussive Piling under Noise Control
Ordinance. The predicted cumulative construction
noise levels at representative NSRs under unmitigated scenario ranged from 58
to 72 dB(A), resulting in exceedance of the daytime construction noise criteria
during normal working hours at 3 nos. of NSRs.
By employing quiet PMEs, temporary noise barriers, noise jackets,
mufflers, and limiting the number of plants operated concurrently, the
mitigated noise levels at representative NSRs were predicted to be 55 to 65
dB(A). Therefore, adverse construction
noise impact is not anticipated.
3.2.2
In addition, it is recommended that more
detailed construction work programme should be considered before actual
construction work is undertaken by the contractor, and applicable noise mitigation
measures should be implemented according to the actual site condition and
constraints, in order to minimise the potential cumulative construction noise
impact with concurrent projects. In particular, the contractor shall keep close
liaison with the nearby educational institutions, and special arrangement on
PME operations should be determined during school examination periods.
Operation Phase
3.2.3
Fixed plant noise and off-site traffic noise were identified as
potential operational noise from the Depot.
3.2.4
Identified fixed plant noise sources
including (a) workshop vehicle repair activities and (b) Mechanical Ventilation
and Air Conditioning System (MVAC) installation have been assessed according to
Technical Memorandum for the Assessment
of Noise from Places other than Domestic Premises, Public Places or
Construction Sites under Noise Control Ordinance. With a
maximum allowable Sound Power Level (SWL) of 90 dB(A) for each of the plant
room equipment and measured SWL for workshop vehicle repair activities, the
results revealed that the predicted maximum noise levels at the identified NSRs
would be 46.6 to 58.2 dB(A) at day-time and 43.7 to 54.9 dB(A) at night-time,
which would comply with noise criteria. With the implementation of the
recommended mitigation measures for both workshop vehicle repair activities and
MVAC installation, adverse impact to the NSRs due to fixed plant noise would
not be anticipated during operation phase.
3.2.5
The off-site traffic noise contribution
generated by the Depot for the short-term period and long run are represented
by Year 2017 and 2032 respectively which would be the occupation year and 15
years after operation. Based on the insignificant off-site traffic generation and routings
for the Project development, the assessment results demonstrated that the
operation of the FEHD Depot would introduce insignificant traffic noise impact
less than 1.0 dB(A) at all representative NSRs for short-term period and in the
long run.
3.2.6
Moreover, environmental benefits by the development of the Depot as a
noise tolerate building fronting some of the NSRs could also contribute traffic
noise reduction by up to 1.7dB(A).
3.3
Water
Quality and Sewage Impact
Construction Phase
3.3.1
Potential water pollution sources have
been identified as construction site run-off, sewage from workforce, and
potential risk of chemical spillage. Mitigation measures including the
implementation of the construction site practices in accordance with the EPD’s
ProPECC PN 1/94 Construction Site Drainage, provision and management of portable
toilets on-site, and preventive measures to avoid accidental chemical spillages
are recommended to mitigate any adverse water quality impacts, based on which
adverse residual impacts would not be anticipated.
Operation Phase
3.3.2
There would be sewage discharged and
treatment implications during the operation of this Project. Sewage from the
Depot is anticipated to be generated mainly
from the toilet and shower facilities in the workshop and office, while
potentially polluted run-off is anticipated to be generated from the cleaning
activities at the vehicle washing
bays and maintenance areas. Automatic vehicle
washing machine equipped with simple filtration and disinfection before reuse
by the machine will be provided. With
the implementation of the recommended mitigation measures based on the findings
of this EIA study, adverse water quality impact would not be anticipated.
3.4
Waste
Manamgenet Implications and Land Contamination
Construction Phase
3.4.1
The major waste stream identified during construction phase will be
C&D materials, followed by C&D wastes, chemical wastes and general
refuse. Measures at design stage to reduce waste generation were
recommended. Adoption of driven H-pile
was proposed to avoid generation of excavation wastes and marine sediment.
Estimated amount of C&D materials to be reused
on-site or off-site as public fill would be approximately 40,800m3. Opportunities for minimising waste
generation via on-site sorting and reusing at least
one-third of excavated soil for backfilling upon the completion of excavation
works for substructure were
identified.
3.4.2
Provided that the
recommended waste management measures are implemented, unacceptable
environmental impacts would not be expected to arise from the handling,
storage, transportation and disposal of wastes and chemicals during the
construction phase of the Project.
3.4.3
Land contamination during
construction phase would not be anticipated.
Operation Phase
3.4.4
The waste
streams generated during the operation phase of the Project would be chemical
wastes arising from
repairing and maintenance activities of vehicles and general
refuse. Measures to ensure proper
treatment and disposal of these wastes have been
provided and no significant waste implications would be
anticipated.
3.4.5
In view of the paved site and recommended preventive measures, it is
anticipated that land contamination during operation would be avoided.
3.5
Landscape
and Visual Impact
Construction Phase
3.5.1
Out of the total 16 trees surveyed within the Site,
the Project will result in felling of 15 trees which are of the invasive exotic
species, Leucaena
leucocephala (銀合歡),
having direct
conflict with the proposed car parking spaces and access road for the vehicle
depot. Given the limited footprint of the Depot, no significant impacts on the identified
LRs and LCAs will be anticipated except for impacts on Vacant Land Vegetation
(LR 5-3) and Open Space/Vacant Land (LCA 4) due to felling of 15 common trees
of the Site.
3.5.2
Due to the close proximity of Traveller of Yen Chow Street West (VSR
T02), Traveller of Yen Ming Road (VSR T03) as well as Users/ Visitors of
Wholesale Food and Fish Market (VSR P02), to the Site where these Visual
Sensitive Receivers may have glimpse to full view of the Site, the construction
activities may impose some visual impact on the viewers. Nevertheless, in view of their transient
nature of use, the magnitude of change of VSR T02, VSR T03 and VSR P02 due to
the construction activities is considered as small. As a result, with low sensitivity and small
magnitude of change, slight visual impacts are anticipated.
3.5.3
With the implementation of mitigation
measures such as control of construction activities and temporary landscape
treatment during construction phase, the Project will inevitably result in some
landscape impact but no adverse visual impact during the construction phase.
Operation Phase
3.5.4
To compensate for the trees lost during
construction phase, 27 compensatory trees will be planted on-grade and on
3/F. Landscape design which includes an area of
about 630m2 of tree and shrub planting on ground floor pedestrian
zone, as well as an area of about 1,400m2 of tree and shrub planting
on roof garden would be provided in place before the completion of construction
work of the Project.
3.5.5
Following the completion of construction
activities, the magnitude of change would be further reduced as the proposed
landscape mitigation measures would help screen and soften the operational
phase impact of the building on the surrounding landscape. At Year 10, the trees and shrub planting will
be matured and further screening views for the surrounding VSRs. On the contrary, ground floor planting,
vertical greening and roof gardens will be provided for the proposed Depot during operation phase. Both landscape and visual impact would become
negligible in Year 10 when the mitigation measures are already established.
3.5.6
Comparing with the original setting of the
Site before the proposed project where undesirable and weedy species are located
at the Site, the overall landscape character and visual quality of the Site
would be improved, with the provision of landscape design including ground
floor planting at pedestrian zone, vertical greening and roof gardens for the
Depot.
According to Annex 10 of EIAO-TM, the landscape and visual character of
the Site have been complemented and therefore landscape and visual impact
arising from the Depot is considered as beneficial.
4.1.1
Based on the assessment on various environmental
parameters, programme and methodologies, Environmental Monitoring and Audit
(EM&A) are recommended for evaluating the environmental performance and
compliance or implementing the Project. The EM&A programme provides
systematic procedures for monitoring, auditing and minimising the environmental
impacts associated with the construction and operation of the Project.
4.1.2
Regular audit for all aspects through site inspection and supervision
during construction phase is recommended.
Environmental monitoring for airborne noise in Leq-30min
during construction phase and odour removal efficiency for the odour
removal unit during the first year of operation are also proposed.
5.1.1
EIA for the Project has been conducted to assess the likely environmental
impacts arising from the construction and operation of the Project in
accordance with the EIA Study Brief.
With the implementation of recommended environmental measures as well as
the EM&A programme, where necessary and practicable, during construction
and operation phases, it is envisaged that the adverse residual impacts would
not be anticipated.