6
waste management implication
6.1.1.1
This section identifies
the type of wastes that are likely to be generated from the construction
activities of the Project and evaluates the potential environmental impacts
that may result from waste generated. It is unlikely for the operation of the
Project to generate considerable amount of wastes, adverse environmental
impacts are thus not anticipated.
6.1.1.2
Mitigation measures and
good site practices regarding the waste handling, storage, collection and disposal
are recommended with reference to relevant waste legislation and guidelines. Handling
and disposal of sediments are also discussed in this section.
6.2.1
General
6.2.1.1
The criteria and guidelines
for assessing waste management implications are outlined in Annex 7 and 15 respectively
in the Technical Memorandum on Environmental Impact Assessment (EIAO-TM).
6.2.1.2
The following legislation
relates to the handling, treatment and disposal of wastes in the Hong Kong Special
Administrative Region (SAR):
·
Waste Disposal Ordinance (Cap. 354);
·
Waste Disposal (Chemical Waste)
(General) Regulation (Cap. 354C);
·
Waste Disposal (Charges for Disposal
of Construction Waste) Regulation (Cap. 354N);
·
Land (Miscellaneous Provisions)
Ordinance (Cap. 28);
·
Public Health and Municipal Services
Ordinance Public Cleansing and Prevention of Nuisances Regulation (Cap.
132BK); and
·
Dumping at Sea Ordinance (Cap.
466)
Waste Disposal Ordinance
(Cap. 354)
6.2.1.3
The Waste Disposal Ordinance
(WDO) prohibits the unauthorised disposal of wastes. Construction waste is defined
under Cap. 354N of the WDO as any substance, matter or thing that is generated and
abandoned from construction works regardless if it has been processed or stockpiled
before being abandoned, excluding sludge, screenings or any matter removed or generated
from desludging, desilting or dredging works. Under WDO, waste can be disposed of
only at designated waste disposal facilities licensed by the Environmental Protection
Department (EPD).
Waste Disposal (Chemical
Waste) (General) Regulation (Cap. 354C)
6.2.1.4
Issued under the WDO, the
Waste Disposal (Chemical Waste) (General) Regulation controls the possession, storage,
collection, transport and disposal of chemical wastes. EPD has also issued three
guidelines detailing how the Contractor should comply with the regulations on chemical
wastes, namely A Guide to the Chemical Waste Control Scheme (2016), A Guide to the Registration
of Chemical Waste Producers (2016) and Code of Practice on the Packaging, Labelling
and Storage of Chemical Wastes (1992).
Waste Disposal (Charges for
Disposal of Construction Waste) Regulation (Cap. 354N)
6.2.1.5
Under the Waste Disposal (Charges
for Disposal of Construction Waste) Regulation, construction waste delivered to a landfill for disposal must not contain
more than 50% by weight of inert material. Construction waste delivered to a sorting
facility for disposal must contain more than 50% by weight of inert material, and
construction waste delivered to a Public Fill Reception Facility (PFRF) for disposal
must consist entirely of inert material.
Land (Miscellaneous Provisions)
Ordinance (Cap. 28)
6.2.1.6
The inert portion of Construction
and Demolition (C&D) materials (including rocks, soil, broken concrete, building
debris etc.) may be taken to Public Fill Reception Facilities (PFRFs) operated
by the Civil Engineering and Development Department (CEDD). PFRFs usually form part
of land reclamation schemes. The Land (Miscellaneous Provisions) Ordinance requires
that individuals or companies who deliver public fill to the PFRFs are required
to obtain Dumping Licences. The licences are issued by CEDD under delegated authority
from the Director of Lands.
Public Health and Municipal
Services Ordinance Public Cleansing and Prevention of Nuisances Regulation (Cap.
132BK)
6.2.1.7
The Public Cleansing and
Prevention of Nuisances Regulation provides control on illegal dumping of wastes
on unauthorised / unlicensed sites. The illegal dumping of wastes
can lead to a fine and/or imprisonment.
Dumping at Sea Ordinance
(Cap. 466)
6.2.1.8
This Ordinance came
into operation in April 1995 and empowers the Director of Environmental
Protection (DEP) to control the disposal and incineration of substances and
particles at sea for the protection of the marine environment. Under the Ordinance, a dumping permit from
the DEP is required for the disposal of regulated substances within and outside
the waters of Hong Kong. The permit
contains terms and conditions which include the following specifications, but
not limited to:
·
Type and quantity of substances
permitted to be dumped;
·
Location of the disposal
grounds;
·
Requirement of equipment for
monitoring the disposal operations; and
·
Environmental monitoring
requirements.
6.2.1.9
Marine disposal of any
dredged/excavated sediment is subject to control under the Dumping at Sea
Ordinance (DASO). Dredged/excavated sediment destined for marine disposal is
classified based on its contaminant levels with reference to the Environment,
Transport and Works Bureau Technical Circular (Works) (ETWB TCW) No. 34/2002
Management of Dredged/Excavated Sediment. The ETWB TCW No. 34/2002 stipulated a
set of sediment quality criteria or Chemical Exceedance Levels (CEL) for
contaminants including metals, metalloid and organic pollutants.
6.2.2
Other Relevant Environmental Guidelines
6.2.2.1
Other environmental relevant
circulars/guidelines applicable to waste management practices for this Project include:
·
Works Branch Technical Circular
(WBTC) No. 2/93 Public Dumps;
·
WBTC No. 2/93B Public Filling Facilities;
·
WBTC No. 12/2000 Fill Management;
·
ETWB TCW No. 34/2002 Management
of Dredged / Excavated Sediment;
·
ETWB TCW No. 19/2005 Environmental
Management on Construction Sites;
·
Development Bureau Technical Circular
(Works) (DevB TCW) No. 06/2010 Trip-ticket System for Disposal of Construction and
Demolition Material;
·
DevB TCW No. 08/2010 Enhanced Specification
for Site Cleanliness and Tidiness;
·
DevB TCW No. 09/2011 Enhanced Control
measures for Management of Public Fill;
·
Code of Practice on the Packaging,
Labelling and Storage of Chemical Wastes (EPD);
·
A Guide to the Chemical Waste Control
Scheme (EPD); and
·
Section 4.1.3 of Chapter 4 of the
Project Administration Handbook (PAH) for Civil Engineering Works, Management of
Construction/Demolition Materials including Rocks.
6.2.2.2
The WBTC No. 2/93 Public Dumps documents the current policy related to the
disposal of C&D materials. C&D materials that are wholly inert, i.e. public
fill, should be taken to PFRFs for reuse instead of being disposed of at landfill.
6.2.2.3
Under DevB TCW No. 6/2010
Trip Ticket System for Disposal of Construction and Demolition Materials, for all contracts that are expected to generate inert C&D materials
requiring disposal from site, the project office shall write to the Public Fill
Committee (PFC) through Secretary of the PFC to request a designated disposal ground
for incorporation into the tender documents. For contracts where the estimated amount
of non-inert C&D materials requiring disposal at landfill facilities equals
to or exceeds 50 m3, the project office shall seek confirmation from
the DEP in terms of the availability of landfill facilities for disposal of such
materials and the DEP will designate landfill facilities, if available, for the
contracts. For contracts where the estimated amount of non-inert C&D materials
to be generated from the contract is less than 50 m3, the project office
is not required to apply to DEP for designated landfill facilities but it should
still specify in the tender documents of the appropriate landfill facilities for
disposal.
6.2.2.4
Further measures have been
introduced under Paragraph 4.1.3 of Chapter 4 of the PAH for Civil Engineering Works
to enhance the management of C&D materials, and to minimize its generation at
source. The enhancement measures include:
·
Drawing up a Construction and Demolition
Materials Management Plan (C&DMMP) at an early design stage to minimize C&D
materials generation and to encourage proper management of such materials;
·
Vetting of the C&DMMP prior
to upgrading of the project to Category A in the Public Works Programme; and
·
Providing the contractor with information
from the C&DMMP in order to facilitate the preparation of Waste Management Plan
(WMP) and to minimize C&D materials generation during construction.
6.2.2.5
The ETWB TCW No. 19/2005
Environmental Management on Construction Sites introduces additional measures to
enhance waste management on construction sites. The circular sets out the policies
and procedures that require the contractors to prepare and implement an Environmental
Management Plan (EMP), which includes the WMP to encourage on-site sorting of C&D
materials and to minimize generation of C&D materials during the course of construction.
·
Type 1 Open Sea Disposal or
Open Sea Disposal in Dedicated Sites;
·
Type 2 Confined Marine
Disposal; and
·
Type 3 Special
Treatment/Disposal.
6.2.2.7
For Type 3 disposal,
the Project Proponent shall be responsible for identifying and agreeing with
the DEP the most appropriate treatment and/or disposal arrangement.
6.3.1.1
The Project covers
Tai Wai and Sha Tin area. The alignment is adjacent to residential, industries,
schools, vegetation area and across Shing Mun River Channel and with depressed
and underpass roads adjacent to Lion Rock Tunnel Road near Sha Tin Tau Village.
6.4.1
Construction Phase
6.4.1.1
Potential waste
mainly generated from the construction of the Project. The construction
activities to be carried out for the Project include site clearance, slope work,
demolition /removal of existing facilities, excavation, piling works,
backfilling, foundation works, installation of new facilities, road works and
pavement etc. As a result, the types of waste associated with these activities
include:
·
C&D materials;
·
Excavated sediments;
·
Chemical wastes; and
·
General refuse
6.4.2
Operational Phase
6.4.2.1
No waste is
expected to be generated during the operation of the Project.
6.5.1.1
The assessment of the
potential waste management implications during the construction phase of the
Project has been conducted in accordance with Annexes 7 and 15 of the EIAO-TM,
including the following tasks:
·
Estimation of the types and
quantities of the wastes generated;
·
Evaluation of opportunities for
waste reduction and re-use;
·
Identification of disposal
options for each type of wastes;
·
Assessment of potential
environmental impacts arising from the waste management with respect of
potential hazards, air and odour emissions, noise, wastewater discharge, and
public transport; and
·
Assessment of the impacts
caused by handling, collection, transportation and re-use /disposal of wastes.
6.5.1.2
Prior
to considering the disposal options for various types of waste, opportunities
for reducing waste generation, on-site or off-site reuse and recycling have
been evaluated. Measures which can be taken in the construction phase for maximizing
waste reduction have been separately considered.
Practices to promote segregation of waste materials are additionally considered
for advancing the waste management efficiency.
6.5.1.3
After
considering all the opportunities for reducing waste generation and maximizing
reuse, the types and quantities of the waste required to be disposed of have
been estimated and the disposal options for each type of waste have been
described. The disposal method recommended for each type of waste has taken
into account the result of the assessment. The impacts caused by handling
(including stockpiling, labelling, packaging and storage), collection and reuse
/ disposal of waste have been addressed and appropriate mitigation measures
have been proposed.
6.6.1
Construction Phase
Construction
and demolition (C&D) materials
6.6.1.1
C&D materials would
be generated from construction works of the Project such as demolition of the existing
subway, site clearance, site formation and excavation for underpass and
depressed roads. The C&D materials would comprise both inert C&D materials
(i.e. public fill including soil, rock, concrete & etc.) and non-inert C&D
materials (i.e. C&D waste including vegetation, timber, paper, plastic etc.).
During general layout design, devising construction method described in Section 2 and planning of construction programme, considerations have been given
to minimize the generation of inert C&D materials and maximize the use of
these generated inert C&D materials for other construction works. In order
to minimize generation of excavated materials and for smooth connection with
existing Sha Tin Road (STR), the road levels of the newly formed Sha Tin Road
(STR) carriageway remain similar to that of the existing STR carriageway.
Excavated materials generated could also be stored temporarily on-site/at
stockpiling areas and used for back-filling e.g. backfilling for retaining
walls and filling for formation of at-grade slip road SR6-1.
6.6.1.2
Based on the latest layout,
it was estimated that the total quantity of C&D materials generated would be
323,464 m3 (23,850 m3 of non-inert materials and 299,614
m3 of inert materials). However, it should be noted that these
quantities are initial estimates only and would need to be further reviewed and
updated as the design progresses.
6.6.1.3
For inert C&D
materials, they would be reused on-site as far as practicable subject to the
review of detailed design stage before exported off site for or delivered to
PFRF (Tseung Kwan O Area 137 Fill Bank) for beneficial use in other projects
with potential fill demand. For non-inert C&D materials, upon exhaustion of
reuse/ recycling effort, they would be disposed of at landfill. It is the Contractors
responsibility to separate the inert and non-inert C&D materials on site. A
stockpiling area should be assigned to facilitate the sorting of inert and
non-inert C&D materials and store the inert C&D materials for
subsequent backfilling. Subject to
actual on-site condition, limited spatial area is available within the site
boundary, land required for stockpile area would be minimized as far as
possible. The existing fee-paying public car park on Man Lam Road near Caltex
Tai Wai petrol filling station (Lot No. STT2211) and an area between proposed
T4 (EB) and T4 (WB) (at underpass section to northeast of Sha Tin Tau Village)
have been identified as stockpiling areas before C&D materials are reused
or transported to landfill/ public fill (for locations, refer to Figure 6.1). Details will be
reviewed in design stage, in case stockpiling areas are found to be required,
they would be implemented with mitigation measures such as covering the
materials during heavy rainfall. Around 45,504 m3 of inert C&D
materials from construction works, mainly soil, is expected to be able to be
reused on-site as backfill material. A summary of the C&D materials
estimates during construction phase is shown in Table 6.1.
Table 6.1 Estimated Quantities of C&D Materials during
Construction Phase
|
Material Type
|
Estimated Amount of C&D Materials to be Generated (m3)
|
Total Estimated Amount of C&D Materials (m3)
|
|
Inert C&D Materials
|
Non-inert C&D Materials
|
|
C&D Materials
|
299,614
|
23,850
|
323,464
|
|
Reuse on Site
|
45,504
|
405
|
45,909
|
|
Deliver to Public Fills
|
254,110
|
0
|
254,110
|
|
Disposal of at Landfills
|
0
|
23,445
|
23,445
|
Note:
1. All in-situ volume
6.6.1.4
The amount of
non-inert materials generated during the construction phase is expected to be
around 23,850 m3. The non-inert C&D
materials would be disposed of at the SENT Landfill via Kwun Tong Bypass while
surplus inert C&D materials (general fill) would be transported to Tseung
Kwan O (TKO) Area 137 Fill Bank or other construction sites with potential fill
demand. CEDD shall enquire with the EPD on the availability of landfill and
acceptability of the waste. The Contractor should liaise with CEDD on the
arrangement of and obtain all necessary permits on disposal at the fill bank.
The
disposal of C&D materials would require maximum 60 trucks per day for
transporting C&D materials to SENT Landfill and TKO
137 Fill Bank. With the implementation
of measures recommended in Section 6.7, no adverse environmental impacts (including potential hazard, air and
odour emissions, noise and wastewater discharge) and public transport impact
caused by handling, collection, transportation and reuse/disposal of C&D
materials are expected.
Excavated
Sediments
Land-Based
Sediment
6.6.1.5
The central portions of the proposed Trunk Road
T4 alignment is situated on a reclaimed land
Under the Project, there would be construction of approximately 400 m
long of depressed road and underpass section (near Lion Rock Tunnel Road and
Che Kung Miu Road intersection), as well as construction of piers for land
section of the viaduct using bored pile method.
Based on the existing ground investigation (GI) information, no
land-based sediments are anticipated within the proposed Trunk Road T4
alignment. It is not expected that there
will be land-based sediment generated during the works.
Marine-Based
Sediment
6.6.1.6
The proposed Trunk Road
T4 comprises of a viaduct section across the Shing Mun River Channel, which
would require construction of piled foundation.
To keep sediment in place as far as possible, no open sea dredging of
seabed will be involved during construction.
However, it is inevitable that the marine-based sediment within the
bored piles for the viaduct foundation construction would need to be
excavated. The quantities of marine-based
sediment to be excavated are expected to be 800 m3. The areas with potential excavated
marine-based sediment are shown in Figure 6.1.
6.6.1.7
In order to minimise
off-site disposal, the excavated marine-based sediment is proposed to be reused
on site under the Project (e.g. as backfilling materials). The marine-based sediment would be treated
using stabilization / solidification (S/S) technique prior to reuse by mixing
with cement (e.g. Portland cement). The
sediment will be provided with the necessary strength and any contaminants in
the sediment will be immobilised in the cement/sediment mix after the S/S
process. The treated materials will be
tested for the Toxicity Characteristic Leaching Procedure (TCLP) and Unconfined
Compressive Strength (UCS) and should meet the Universal Treatment Standards
(UTS) with reference to EPDs Practice Guide for
Investigation and Remediation of Contaminated Land and the UCS standard prior to reuse. If the treated materials did not
meet the UTS and UCS standards, the materials will be re-treated and
re-tested. Pilot-scale trial should be
carried out before the commencement of treatment to determine the cement/sediment
ratio that could achieve the treatment standards. Off-site sediment disposal
should only be considered as the last resort in case sediment treatment / reuse
not possible and should follow the procedures in ETWB TCW No. 34/2002.
6.6.1.8
The estimated quantities
of marine-based sediment and the proposed handling methods are summarised in Table
6.3. Sediments that meet
the treatment standards are considered as suitable for reuse on site. The recommended
mitigation measures are discussed in Section 6.7. No adverse waste management
implications are anticipated if the recommended mitigation measures are
implemented.
Chemical
Waste
6.6.1.9
The
maintenance and servicing of construction plant and vehicles may generate a negligibly
small amount of chemical wastes including:
·
Used paint, engine oils,
hydraulic fluids and waste fuel from plant operation;
·
Spent mineral oils/ cleaning
fluids from plant maintenance; and
·
Spent solvents/ solutions from
equipment maintenance.
6.6.1.10
Since
the construction activities would be carried out in close proximity to watercourses
and drainage systems, chemical wastes arising during the construction phase may
pose environmental, health and safety hazards if not stored and disposed of in an
appropriate manner as stipulated in the Waste Disposal (Chemical
Waste) (General) Regulations (Cap. 354C).
6.6.1.11
It is
difficult to quantify the amount of chemical waste that would arise from the construction
activities since it would depend on the Contractors on-site maintenance requirements
and the amount of plant utilized. However, it is anticipated that the quantity of
chemical waste, such as lubrication oil and solvent produced from plant maintenance,
would be small and in the order of a few cubic meters per month. The amount of chemical
waste to be generated would be quantified in the WMP to be prepared by the Contractors.
6.6.1.12
Materials
classified as chemical waste shall require special handling and storage
arrangements by the Contractor. All chemical waste shall be collected by a
licensed collector and be disposed at a licensed chemical waste treatment and
disposal facility such as Chemical Waste Treatment Centre (CWTC) at Tsing Yi.
Unused chemical or those with remaining functional capacity would be reused and
recycled on site or by licensed companies whenever possible. Mitigation and
control requirements for chemical wastes are detailed Section 6.7. Provided that the handling, storage and disposal of
chemical wastes are in accordance with these requirements and the Code of
Practice on Packaging, Labelling and Storage of Chemical Wastes published by
EPD, adverse environmental impacts (including potential hazard, air and odour
emissions, noise, wastewater discharge and ecology) and public transport impact
will be negligible.
General
Refuse
6.6.1.13
General
refuse comprising general site wastes, such as packaging and container waste from
materials and equipment used on the site, food scraps, waste paper, empty containers
etc. would be generated by workforce during the construction phase. Improper collection
and removal of general refuse would give rise to hygiene problems and adverse environmental
impacts to local residents, e.g. odour impacts, and contamination of the nearby
watercourses.
6.6.1.14
The
maximum number of construction workers to be working on site at any one time was
estimated to be about 250. Based on a generation rate of 0.65kg per workers per
day, approximately 163 kg of general refuse would be generated daily during the
construction period. It is expected that the general refuse from construction sites
would be disposed of at NENT Landfill. Given the quantity of general refuse to be
disposed of at landfill would be small, no adverse impact on the operation of landfill
would be anticipated.
6.6.1.15
In
order to minimize the final disposal quantities of general refuse, provision of
sufficient number of recycling bins for the collection of different types of
recyclable waste (including paper, aluminium cans, plastic and glass bottles)
and sufficient number of general refuse bins for the collection of
non-recyclable waste is recommended. The Contractor should implement an
education programme for worker relating to avoiding, reducing, reusing and
recycling of general refuse.
6.6.1.16
The
general refuse will be collected on-site on a regular basis, separately from C&D
materials by an appropriate waste collector to be employed by the Contractor. Prior
to disposal off-site, such refuse will be temporarily put in suitably covered storage
areas / bins where they will have to be regularly cleaned and maintained to avoid
attracting vermin and pests. With proper on-site handling and storage as well as
regular disposal of the wastes, no unacceptable environmental impact would be anticipated.
Recommendations of mitigation measures for managing general refuse are presented
in Section 6.7.
Transportation
Arrangement for Waste Disposal during Construction Phase
6.6.1.17
Land
transport should be used to deliver and dispose of the waste generated from the
Project area to the designated disposal outlets. Referring to Section 6.6.1.4, it is expected there will be maximum 60
trucks per day for transporting waste during the construction phase of the
Project. The tentative transportation
routings for the disposal of various types of wastes generated during the
construction phase of the Project are shown in Table 6.2. The transportation routings may change
subject to the actual traffic conditions of the roads. Nevertheless, with the implementation of
appropriate mitigation measures (e.g. using water-tight containers and covered
trucks), no adverse environmental impacts are expected due to the
transportation of waste.
6.6.1.18
No barging points or
conveyor systems would be established in the Project area. The C&D materials will be reused or recycled
on-site as much as practicable and any surplus would be timely transported out
of construction work area. As presented in Section 6.6.1.3, subject to actual on-site condition, limited spatial area is
available within the site boundary, land required for stockpile area would be
minimized as far as possible. The existing fee-paying public car park on Man
Lam Road near Caltex Tai Wai petrol filling station (Lot No. STT2211) will be
identified as a small-scale stockpiling area before transporting the C&D
materials to landfill/ public fill. Details will be reviewed in design stage,
in case stockpiling areas are found required, they would be implemented with
mitigation measures such as covering the materials during heavy rainfall.
Table 6.2 Tentative Transportation Routings for Waste Disposal During
Construction Phase
|
Disposal Outlet
|
Type of Waste
|
Tentative Transportation
Routing
|
|
South East New Territories
Landfill
|
Non-inert C&D Materials
|
Sha Tin Wai Road, Sha Lek Highway, Tates Carin Tunnel, Kwun Tong
Bypass, Tseung Kwan O Tunnel, Wan Po Road
|
|
Tseung Kwan O Area 137 Fill
Bank
|
Surplus Inert C&D
Materials
|
Sha Tin Wai Road, Sha Lek Highway, Tates Carin Tunnel, Kwun Tong
Bypass, Tseung Kwan O Tunnel, Wan Po Road
|
|
Chemical Waste Treatment
Centre
|
Chemical Waste
|
Tsing Sha Highway / Eagles Nest Tunnel and Route 8 / Stonecutters
Bridge
|
|
North East New Territories
Landfill
|
General Refuse
|
Tai Po Road (Sha Tin Section), Tolo Highway, Fanling Highway, Heung
Yuen Wai Highway, Wo Keng Shan Road
|
6.6.2
Operation Phase
6.6.2.1
It
is expected that no waste will be generated during the operation phase of the
Project. As such it is considered that
there would be no adverse environmental impacts.
Waste
Management Hierarchy
6.7.1.1
The waste management hierarchy
has been applied in the assessment and development of mitigation measures for waste
which aims at evaluating the desirability of waste management methods and includes
the followings in descending preference:
·
Avoidance and reduction of waste
generation;
·
Reuse of materials as far as practicable;
·
Recovery and recycling of residual
materials where possible; and
·
Treatment and disposal according
to relevant laws, guidelines and good practices.
6.7.1.2
Based
on the waste management hierarchy, waste reduction measures are recommended as follows
to reduce impacts and costs arisen from the Project. Recommendations of good site
practices and waste reduction measures would be stated in order to achieve avoidance
and minimization of waste generation in the hierarchy. EMP and trip-ticket system
are recommended for monitoring management of waste.
Good
Site Practices
6.7.1.3
It is anticipated that adverse
impacts would not arise on the construction site, provided that good site practices
are strictly followed. Recommendations for good site practices during the construction
phase include:
·
Nomination of approved personnel,
such as a site manager, to be responsible for good site practices, and making arrangements
for collection of all wastes generated at the site and effective disposal to an
appropriate facility;
·
Training of site personnel in proper
waste management and chemical waste handling procedures;
·
Provision of sufficient waste reception/
disposal points, of a suitable vermin-proof design that minimises windblown litter;
·
Arrangement for regular collection
of waste for transport off-site and final disposal;
·
Appropriate measures to minimise
windblown litter and dust during transportation of waste by either covering trucks
or by transporting wastes in enclosed containers;
·
Regular cleaning and maintenance
programme for drainage systems, sumps and oil interceptors;
·
A recording system for the amount
of wastes generated, recycled and disposed (including the disposal sites) should
be proposed; and
·
Preparation of a WMP as a part
of the EMP in accordance with ETWB TCW No. 19/2005 Environmental Management on
Construction Sites and submit to the Engineer / Architect for approval.
6.7.1.4
In order
to monitor the disposal of C&D material at landfills and public filling areas,
as appropriate, and to control fly tipping, a trip-ticket system should be included
as one of the contractual requirements to be implemented by an Environmental Team
undertaking the monitoring and auditing work. Warning signs should also
be displayed to remind the designated disposal sites. CCTV should be installed
at the vehicular entrance and exit of the site as additional measures to
prevent fly-tipping. One may refer
to DEVB TCW No.6/2010 for details.
Waste
Reduction Measures
6.7.1.5
Good management and control
of construction site activities / processes can minimize the generation of waste.
Waste reduction is best achieved at the planning and design stage, as well as by
ensuring the implementation of good site practices. Recommendations to achieve waste
reduction include:
·
Segregate and store different types
of construction related waste in different containers, skips or stockpiles to enhance
reuse or recycling of materials and their proper disposal;
·
Provide separate labelled bins to
segregate recyclable waste such as aluminium cans from other general refuse generated
by the work force, and to encourage collection by individual collectors;
·
Any unused chemicals or those
with remaining functional capacity shall be recycled;
·
Maximize the use of reusable steel
formwork to reduce the amount of C&D material;
·
Prior to disposal of C&D waste,
it is recommended that wood, steel and other metals shall be separated for re-use
and / or recycling to minimise the quantity of waste to be disposed of to landfill;
·
Adopt proper storage and site practices
to minimise the potential for damage to, or contamination of, construction materials;
·
Plan the delivery and stock of construction
materials carefully to minimize the amount of surplus waste generated;
·
Adopt pre-cast construction method
instead of cast-in-situ method for construction of concrete structures as much as
possible; and
·
Minimise over ordering of concrete,
mortars and cement grout by doing careful check before ordering.
6.7.1.6
In addition
to the above measures, other specific mitigation measures are recommended below
to minimize environmental impacts during handling, transportation and disposal of
wastes.
Storage,
Collection and Transportation of Waste
·
Waste should be handled and
stored well to ensure secure containment to minimize the potential of
pollution;
·
Maintain and clean storage
areas routinely;
·
Provide stockpiling area with
covers and water spraying system to prevent materials from wind-blown or being
washed away; and
·
Designate different locations
for stockpiling each material to enhance reuse.
6.7.1.8
Licensed waste
collectors should be employed for the collection and transportation of waste
generated. The following recommendations should be implemented to minimize the
impacts:
·
Remove waste in timely manner;
·
Employ the trucks with cover or
enclosed containers for waste transportation;
·
Obtain relevant waste disposal
permits from the appropriate authorities; and
·
Dispose of waste at licensed
waste disposal facilities.
C&D Material
6.7.1.9
In order
to monitor, document and verify the disposal of C&D materials at landfills
and public fill reception facilities, as appropriate, and to control fly
tipping, a trip-ticket system in accordance with DevB TCW No. 6/2010 Trip
Ticket System for Disposal of Construction and Demolition Materials should be
implemented. A Construction and Demolition Material Management Plan
(C&DMMP) will be submitted together with the EIA Report to PFC for approval
as required under Section 4.1.3 Construction and Demolition Materials of the
Project Administration Handbook (PAH) for Civil Engineering Works.
6.7.1.10
The
C&D materials generated should be sorted on-site into inert C&D
materials and non-inert C&D waste.
To minimize the impact resulting from collection and transportation of
C&D materials as far as practicable, C&D waste, such as wood, plastic,
steel and other metals should be reused or recycled and, as a last resort,
disposed to landfill. The existing fee-paying public car park on Man Lam Road near Caltex
Tai Wai petrol filling station (Lot No. STT2211) and an area between proposed
T4 (EB) and T4 (WB) (at underpass section to northeast of Sha Tin Tau Village)
have been identified as stockpiling areas before C&D materials are reused
or transported to landfill/ public fill (for locations, refer to Figure 6.1). Inert
C&D materials will be recycled and reused as far as practicable. With
reference to Table 6.2, inert C&D materials are expected to be
disposed to Tseung Kwan O Area 137 Fill Bank. Within the stockpiling areas, the
following measures should be taken to control potential environmental impacts
or nuisance:
·
Proper handling and storage of
waste by means of covers and/or water spraying system to minimize the potential
environmental impact and to prevent materials from wind-blown or being washed
away;
·
Covering materials during heavy
rainfall;
·
Locating stockpiles to minimize
potential visual impacts;
·
Warning signs should be put up
to remind the designated disposal sites. CCTV should be installed at the
vehicular entrance and exit of the site as additional measures to prevent
fly-tipping; and
·
Minimizing land intake of
stockpile areas as far as possible
Excavated
Sediments
6.7.1.11
The sediment
should be excavated, handled, treated, transported and/or disposed of in a
manner that would minimize adverse environmental impacts. In order to minimise off-site disposal, the excavated marine-based
sediment is proposed to be reused on site under the Project (e.g. as
backfilling materials). The marine-based
sediment would be treated using stabilization / solidification (S/S) technique
prior to reuse by mixing with cement (e.g. Portland cement). The sediment will be provided with the
necessary strength and any contaminants in the sediment will be immobilised in
the cement/sediment mix after the S/S process.
The treated materials will be tested for the Toxicity Characteristic
Leaching Procedure (TCLP) and Unconfined Compressive Strength (UCS) and should
meet the Universal Treatment Standards (UTS) with reference to EPDs Practice Guide for Investigation and Remediation of Contaminated Land and the UCS standard prior to reuse. If the treated materials did not
meet the UTS and UCS standards, the materials will be re-treated and
re-tested. Pilot-scale trial should be
carried out before the commencement of treatment to determine the cement/sediment
ratio that could achieve the treatment standards. Off-site sediment disposal
should only be considered as the last resort in case sediment treatment / reuse
not possible and should follow the procedures in ETWB TCW No. 34/2002.
6.7.1.12
Requirements
of the Air Pollution Ordinance (Construction Dust) Regulation, where relevant,
shall be adhered to during excavation, treatment, transportation and/or
disposal of the sediment.
6.7.1.13
Any
treatment area for the excavated sediment should be confined for carrying out
the cement S/S process and any temporary stockpiling. The area should be designed to prevent
leachate from entering the ground.
Leachate, if any, should be collected and discharged according to the
Water Pollution Control Ordinance (WPCO).
6.7.1.14
In
order to minimize the exposure to contaminated materials, workers shall, if
necessary, wear appropriate personal protective equipments (PPE) when handling
contaminated sediments. Adequate washing
and cleaning facilities shall also be provided on site.
6.7.1.15
Stockpiling
of contaminated sediments should be avoided as far as possible. If temporary stockpiling of contaminated
sediments is necessary, the excavated sediment should be covered by tarpaulin
and the area should be placed within earth bunds or sand bags to prevent
leachate from entering the ground, nearby drains and surrounding water
bodies. The stockpiles should be
completely paved or covered by linings in order to avoid contamination to
underlying soil or groundwater. Separate
and clearly defined areas should be provided for stockpiling of contaminated
and uncontaminated materials. Leachate,
if any, should be collected and discharged according to the Water Pollution
Control Ordinance (WPCO).
6.7.1.16
In
order to minimize the potential odour / dust emissions during excavation and
transportation of the sediment, the excavated sediments shall be wetted during
excavation / material handling and shall be properly covered when placed on
trucks or barges. Loading of the
excavated sediment to the barge shall be controlled to avoid splashing and
overflowing of the sediment slurry to the surrounding water.
6.7.1.17
Should
marine disposal of sediment be unavoidable at later stage upon exhaustion of
reuse options, separate submissions (e.g. Sediment Sampling and Testing Plan
(SSTP) and Sediment Quality Report (SQR)) shall be submitted to EPDs Marine
Dumping Control Section / Territorial Control Office if application of dumping
permit under DASO is required. The rationale for sediment removal/disposal
will also need to be submitted to the Marine Fill Committee (MFC)/CEDD for
agreement in accordance with ETWB TC(W) No. 34/2002.
Chemical
Waste
6.7.1.18
If chemical waste is produced at the
construction site, the Contractor will be required to register with the EPD as
a chemical waste producer and to follow the guidelines stated in the Code of
Practice on the Packaging, Labelling and Storage of Chemical Wastes. Suitable containers compatible with the
chemical wastes should be used, and incompatible chemicals should be stored
separately. Appropriate labels should be
securely attached on each chemical waste container indicating the corresponding
chemical characteristics of the chemical waste, such as explosive, flammable,
oxidizing, irritant, toxic, harmful, corrosive, etc. The Contractor shall employ a licensed
collector to transport and dispose of the chemical wastes, to the licensed
Chemical Waste Treatment Centre (CWTC), or other licensed facilities, in
accordance with the Waste Disposal (Chemical Waste) (General) Regulation.
General
Refuse
6.7.1.19
General
refuse should be stored in enclosed bins or compaction units separately from
C&D materials. A reputable waste
collector should be employed by the contractor to remove general refuse from
the site, separately from C&D materials.
An enclosed and covered area is preferred to reduce the occurrence of
wind-blown light materials.
6.7.1.20
The
recyclable component of general refuse, such as aluminium cans, paper and
cleansed plastic containers shall be separated from other wastes. Provision and collection of recycling bins
for different types of recyclable waste shall be set up by the Contractor. The Contractor shall also be responsible for
arranging recycling companies to collect these materials.
6.7.1.21
The
Contractor shall carry out an education programme for workers in avoiding,
reducing, reusing and recycling of materials generation. Posters and leaflets advising on the use of
the bins shall also be provided in the sites as reminders.
6.7.1.22
Table 6.3 provides
a summary of the various waste types likely to be generated during the
construction works and operation of the Project, together with the recommended
handling and disposal methods.