7
waste management implications
7.1.1
This section identifies the types of wastes that
are likely to be generated during the construction and operation phases of the
Project, and evaluates the potential environmental impacts that may result from
handling, transport and disposal of the wastes.
7.1.2
Mitigation measures and good site practices,
including waste handling, storage, collection and disposal have been
recommended with reference to the applicable waste legislation and guidelines. Handling and disposal of sediments are
also discussed in this section.
7.2.1
The criteria and guidelines for assessing waste
management implications are outlined in Annex 7 and 15, respectively, of the Technical
Memorandum on Environmental Impact Assessment Process (TM-EIAO).
7.2.2
The following legislation, which has been used
in assessing potential impacts, relates to the handling, treatment and disposal
of wastes in the Hong Kong 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 (Cap.132BK) 每 Public Cleansing and Prevention of Nuisances
Regulation;
﹞
Dumping at Sea Ordinance (Cap.
466); and
﹞
Buildings Ordinance (Cap 123).
Waste Disposal Ordinance (Cap. 354)
7.2.3
The Waste Disposal Ordinance (WDO) prohibits the unauthorised disposal
of wastes. Construction waste, defined under Cap. 354N of the WDO means any
substance, matter or thing that is generated from construction works and
abandoned, whether or not it has been processed or stockpiled before being
abandoned, but does not include any sludge, screenings or matter removed in or
generated from any 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)
7.2.4
Issued under the WDO, the Chemical Waste (General)
Regulation administers the possession, storage, collection, transport and
disposal of chemical wastes. EPD
has also issued three ＆guideline＊ documents, 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), which detail how the Contractor
should comply with the regulations on chemical wastes.
Waste Disposal (Charges
for Disposal of Construction Waste) Regulation (Cap.354N)
7.2.5
Under the Waste Disposal (Charges for Disposal
of Construction Waste) Regulation enacted in January 2006, 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)
7.2.6
The inert portion of Construction and Demolition
(C&D) materials (including rocks, soil, broken concrete, building debris,
etc.) may be taken to PFRFs. PFRFs
usually form part of land reclamation schemes and are operated by the Civil
Engineering and Development Department (CEDD) and others. The Land (Miscellaneous Provisions)
Ordinance requires that individuals or companies who deliver public fill to the
public fill reception facilities are required to obtain Dumping Licences. The
licences are issued by CEDD under delegated authority from the Director of
Lands.
7.2.7
Individual licences and windscreen stickers are
issued for each vehicle involved.
Under the licence conditions, public fill reception facilities will only
accept soil, sand, rubble, brick, tile, rock, boulder, concrete, asphalt,
masonry or used bentonite. In addition, in accordance with paragraph 12 of the
Development Bureau (DevB) Technical Circular (Works) TC(W) No.6/2010, Public
Fill Committee will advise on the acceptance criteria. The material will, however, be free from
marine mud, household refuse, plastic, metal, industrial and chemical wastes,
animal and vegetable matter and any other materials considered unsuitable by
the public fill reception facility supervisor.
Public Health and Municipal Services
Ordinance 每 Public Cleansing and Prevention of Nuisances Regulation (Cap.132BK)
7.2.8
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)
7.2.9
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.
7.2.10
Marine disposal of any dredged/excavated
sediment is subject to control under the Dumping at Sea Ordinance. Dredged/excavated sediment destined for
marine disposal is classified based on its contaminant levels with reference to
the Practice Notes for Authorized
Persons, Registered Structural Engineers and Registered Geotechnical Engineers
No. 252 ADV-21 (PNAP No. 252 (ADV-21) - Management Framework for Disposal of
Dredged/Excavated Sediment (PNAP No. 252 (ADV-21)). The PNAP No. 252 (ADV-21) stipulated a set
of sediment quality criteria or Chemical Exceedance Levels (CEL) for
contaminants including metals, metalloid and organic pollutants.
Buildings Ordinance (Cap.123)
7.2.11
Private projects are regulated by the Buildings
Ordinance and relevant Practice Notes for
Authorised Persons, Registered Structural Engineers and Registered Geotechnical
Engineers (PNAPs). The PNAP No. 243 (ADV-19) Construction and Demolition Waste has introduced waste prevention
measures to enhance the management of C&D materials which include:
﹞
Identifying opportunities to prevent waste during project planning and
design stage and construction stage; and
﹞
Requiring the contractor to prepare a Waste Management Plan (WMP)
including areas described in PNAP No. 243 (ADV-19) and submit to the project
proponent for agreement.
Environmental Guidelines
7.2.12
Environmental guidelines that are related to
wastes management and disposal include:
﹞
Works Branch Technical Circular
(WBTC) No. 2/93, Public Dumps;
﹞
Works Branch Technical Circular
No. 2/93B, Public Filling Facilities;
﹞
Section 4.1.3 of Chapter 4 of
the Project Administration Handbook (PAH) for Civil Engineering Works,
Management of Construction/Demolition Materials including Rocks;
﹞
PNAP No. 252 (ADV-21) 每
Management Framework for Disposal of Dredged/Excavated Sediment;
﹞
PNAP No. 243 (ADV-19) 每
Construction and Demolition Waste; and
﹞
DevB TC(W) No.6/2010,
Trip-ticket System for Disposal of Construction and Demolition Materials.
7.2.13
The current policy related to the disposal of
C&D materials is documented in the WBTC
No. 2/93, ＆Public Dumps＊. C&D materials that are wholly inert, namely
public fill, should not be disposed of at landfill, but be taken to PFRFs,
which usually form part of reclamation schemes.
7.2.14
In accordance with the DevB TC(W) No. 6/2010 ＆Trip Ticket System for Disposal of
Construction and Demolition Materials＊, all contracts that are expected to
generate inert C&D materials (e.g. soil, broken rock, broken concrete and
building debris, etc) 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 equal or exceed 50m3,
the project office shall seek confirmation from the DEP in terms of the
availability of landfill facilities for disposal of such materials. The DEP will designate landfill
facilities, if available, for the contract. Where the estimated amount of non-inert
C&D materials to be generated from the contract is less than 50m3, the project office is
not required to apply to DEP for designated landfill facilities. However, the project office should still
specify in the tender documents of the appropriate landfill facilities for disposal.
7.2.15
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 including rock, 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;
﹞
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.
7.2.16
Measures have been introduced in PNAP No. 243
(ADV-19) to enhance the management of C&D materials and to minimize its
generation at source. The
enhancement measures include the identification of opportunities to prevent
waste during both the project planning and design stage as well as construction
stage, and preparation of a Waste Management Plan (WMP) to ensure that measures
are implemented during the construction stage for reduction of C&D
materials.
7.2.17
The PNAP No. 252 (ADV-21) sets out the procedure
for seeking approval to and the management framework for marine disposal of
dredged/ excavated sediment. This
Practice Note outlines the requirements to be followed in assessing and
classifying the sediment and explains the marine disposal arrangement for the
classified material. The sediment quality criteria for the classification of
sediment were referred as the Lower
Chemical Exceedance Level (LCEL)
and Upper Chemical Exceedance Level (UCEL). The LCEL and UCEL are
presented in Appendix A of PNAP No. 252 (ADV-21). Subject to the results of the
chemical screening, biological screening may be required to determine the
disposal requirement of the sediment.
There are three types of disposal options for dredged / excavated
sediments stipulated in the PNAP No. 252 (ADV-21):
﹞
Type 1 每 Open Sea Disposal or
Open Sea Disposal in Dedicated Sites;
﹞
Type 2 每 Confined Marine
Disposal; and
﹞
Type 3 每 Special Treatment /
Disposal. For Type 3 disposal, the
Authorized Persons / Registered Structural Engineers shall be responsible for
identifying and agreeing with the DEP the most appropriate treatment and/or
disposal arrangement.
7.3.1
The existing SHD, with an area of about 30
hectares, is sited on reclaimed land in Northshore Lantau and has operated
since 1998 for supporting the operation of the existing TCL, AEL and DRL. The existing SHD comprises stabling sidings
and main depot building located in the centre of the site, permanent way
facilities at the north eastern side, test track at the southern area, and
other supporting facilities including maintenance workshops, utilities and
drainage, ancillary buildings and facilities, traction substation and sewage
pumping station, etc.
7.3.2
Municipal solid waste (MSW) including solid
waste from commercial and industrial sources will be generated during the
operation of SHD. The MSW would be stored on site for further recycling or
disposal, whereas the chemical wastes would be temporarily stored in designated
area and collected by licensed chemical waste collector according to the
requirements under CAP 354C. For
general refuse, a waste collector is arranged to collect the general refuse
from the SHD.
7.4
Identification and Evaluation of Wastes Implications
Assessment Methodology
7.4.1
The criteria and methodology of assessing
potential waste management implications during the construction and operation
phases follows Annexes 7 and 15 of the TM-EIAO respectively, with assessment
approaches provided below:
﹞
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 wastes management with respect of
potential hazards, air and odour emissions, noise, wastewater discharges; and
﹞
Assessment of impacts on the
capacity of waste collection, transfer and disposal facilities.
Construction Phase
7.4.2
The construction activities to be carried out
for the Project would be generate a variety of wastes that can be divided into
distinct categories based on their composition and ultimate method of disposal.
The identified wastes types are:
﹞
Construction and demolition
(C&D) materials;
﹞
General refuse;
﹞
Chemical wastes; and
﹞
Land-based sediments.
Construction and Demolition Materials
7.4.3
C&D materials would be generated from excavation, demolition works, site formation, construction of facilities
and station. These C&D materials comprise both inert (e.g.
rocks, soil, broken concrete, building debris) and non-inert components (e.g. vegetation and wood).
7.4.4
In view of site constraints, scale and nature of
the Project, the available schemes for construction of SHO are limited, generation
of C&D materials has been minimized as far as possible with the following
measures taken in consideration:
﹞
Constant design reviews in
striving to optimise the scheme proposals;
﹞
Minimal interference with
existing structures to reduce the quantity of demolition materials;
﹞
Proposed use of prefabricated
materials where possible; and
﹞
Reuse of existing structures in
the design where possible.
7.4.5
Based on preliminary design information, it was estimated
that the total volume of C&D materials to be approximately 1,319,370 m3
of inert materials (i.e. public fill) and
approximately 18,200m3 of
non-inert materials (i.e. C&D waste).
A C&DMMP will be
prepared and submitted to the PFC for endorsement in accordance with Chapter 4
of the PAH.
7.4.6
A summary of inert and non-inert C&D
materials generated during construction phase is shown in Table 7.1. Due to
limited space of Project site, it may not be practicable to provide a major stockpile
area of inert C&D materials for subsequent backfilling or reuse on site. Nevertheless, there may be small
stockpile area(s) provided on-site for temporary storage before delivery to
disposal outlets. Inert C&D
materials would be reused on-site as far as practicable subject to the review
of detailed design stage before exported off-site for reuse at other concurrent
projects.
Table
7.1 Summary
of Inert and non-inert C&D Materials
Quantities Generated
|
Works
|
Construction Period
|
Approx. Quantities of
Waste To be Generated (m3)
|
|
Excavated Soil(1)
|
Rock(2)
|
Artificial
Hard Material(3)
|
Non-inert
C&D material(4)
|
|
SHO
|
2019 每 2024(5)
|
31,450
|
400
|
6,910
|
3,000
|
|
SHD Stage 1^
|
2019-2024
|
269,000
|
8,000
|
57,200
|
8,000
|
|
SHD Stage 2
|
2024-2028
|
238,000
|
8,600
|
46,760
|
3,000
|
|
SHD Stage 3
|
2028-2032
|
262,000
|
11,000
|
50,250
|
2,000
|
|
SHD Stage 4
|
2032-2034
|
238,000
|
8,600
|
80,000
|
2,000
|
|
Local Access
|
2019-2025
|
2,560
|
40
|
600
|
200
|
|
Total Generation
|
1,041,010
|
36,640
|
241,720
|
18,200
|
|
Disposal Outlet
|
Public Fill Reception
Facilities areas or reclamation sites
|
Public Fill Reception Facilities areas or
reclamation sites
|
Public Fill Reception Facilities areas or
reclamation sites
|
Designated Landfill Site to be agreed
with EPD/CEDD
|
Notes:
^ The
construction of rising mains is included in Stage 1 SHD Replanning Works.
(1) Excavated soil generated from SHD/SHO site formation works or bored piling works,
pile cap construction and excavation works related to the construction of SHD
Topside Development.
(2) ※Rock§ includes all grade rock generated from bored
piling works, pile cap construction and excavation works related to the
construction of SHD Topside Development.
(3) ※Artificial hard material§ includes, but not
limited to, broken concrete, asphalt, bitumen and granular materials, etc.
(4) ※Non-inert C&D material§ includes, but not limited
to, bamboo, timber, paper and plastic, etc.
(5) Construction works for SHO will be completed in end 2024 but the operation of SHO would commence
in the same time with the population
intake in Phase 1 of SHD Topside
Development in 2026.
7.4.7
Non-inert C&D materials generated would be
reused and recycled as much as possible before disposal of at designated landfill
site to be agreed with EPD/CEDD.
7.4.8
The number of construction vehicle
involved in transporting C&D materials/land-based sediment to the disposal
outlets is estimated to be less than 40 nos. per hour, 7am to 7pm, throughout
the construction phase, based on the current engineering design. Upon leaving the construction site,
construction vehicles for transporting C&D materials will enter the North
Lantau Highway (NLH) westbound, turn around at Tung Chung Interchange and via Tuen
Mun-Chek Lap Kok (TM-CLK) Link to Tuen Mun area and ultimately to the
designated disposal outlets (Table 7.1
refers) as agreed with EPD/CEDD during construction phase. It is anticipated that construction
vehicles would not enter the existing Tung Chung New Town and the planned
extension (i.e. Route 1 in Appendix 3.10). For the construction vehicles with the excavated
sediments, it is expected that the sediment will be loaded from construction
vehicles onto the barge at public barging point of which the exact location
will be determined by the contractor(s) and agreed by EPD/CEDD and transported
to the designated disposal sites allocated by MFC. As the construction works
would be conducted in stages, it is expected that the potential environmental
impacts arising from the handling and disposal of the inert C&D materials,
such as air and odour emissions, noise and potential hazard, could be minimized
with the implementation of appropriate measures as detailed in Section 7.5.
General Refuse
7.4.9
During the construction period, the workforce
would generate refuse comprising food scraps, waste paper, empty containers,
etc. Accidental or intentional
release of these refuse to the surrounding environment is not permitted and may
cause negative environmental impacts.
Storage of general refuse on-site will generate adverse environmental
impacts like water contamination, odour nuisance and visual impact if they are
not managed in a proper manner. The
site may also attract vermin and pests if the waste containers are not cleaned
or maintained properly and frequently.
7.4.10
The maximum number of construction workers to be
employed on the Project is estimated to be upto 350 workers in each stage. Based on a generation rate of 0.65 kg per worker per day, approximately 228
kg of general refuse will be generated daily during the construction period.
7.4.11
The refuse should be stored in enclosed bin to
avoid adverse impacts to the surroundings. Recycling bins should be provided to
maximize reuse and recycle volume.
A reputable waste collector should be employed to collect the general
refuse for later disposal of at landfills.
7.4.12
With proper implementation of waste management
practices as detailed in Section 7.5,
it is anticipated that the secondary environmental impacts from collection and
handling of general refuse would be minimal.
Chemical Waste
7.4.13
The maintenance and servicing of construction
plant and equipment may possibly generate a variety of chemical wastes, for
instance, cleaning fluids, solvents, lubrication oil and waste fuel.
7.4.14
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. The
potential hazards include:
﹞
Toxic effects on the workforce;
﹞
Adverse impacts on water
quality and aquatic biota from spills; and
﹞
Fire hazards.
7.4.15
Chemical waste producers are required to apply
for registration as specified in the Guide
to the Registration of Chemical Waste Producers. Materials classified as
chemical wastes will be handled and stored on-site according to the
requirements specified in Code of
Practice on Packaging, Labelling and Storage of Chemical Wastes before collection
by licensed collectors and disposal of at the Chemical Waste Treatment Centre
(CWTC) at Tsing Yi or other licensed facilities. Wherever possible, opportunities will be
taken to reuse and recycle materials. It
is difficult to quantify the amount of chemical waste that would arise from the
construction activities since it would depend on the Contractor＊s on-site
maintenance requirements and the amount of plant utilised. However, it is anticipated that the
quantity of chemical waste, such as lubricating oil and solvent produced from
plant maintenance, would be small to in the order of a few hundred litres per
month. Mitigation and
control requirements for chemical wastes are detailed in Section
7.5. Provided that the
handling, storage and disposal of chemical wastes are in accordance with these
requirements, adverse environmental impacts are not expected.
Sediments
7.4.16
The construction activities to be carried out for
the Project that would generate land-based sediment are the piling works and
excavation works for the proposed SHO, Stage 1 to 4 SHD Replanning Works and local
access located to the west of Reprovisioned SHD. The locations of the proposed
SHO, Stage 1 to 4 SHD Replanning Works and proposed piling works of local
access are shown in Figure No. NEX1062/S/SHD/ACM/Z10/190.
Review of Existing Sediment Quality Data
7.4.17
During the preliminary design stage, site investigation
(SI) was conducted between April and June 2016 to review the geological
characteristic within SHO and SHD Replanning Works area. As there was no
sediment quality data available within the excavation area where sediment is
expected to be encountered, considering the limitation of availability area for
site investigation within an operating depot and minimisation of impact on
existing operation, sediment sampling and testing was also conducted
concurrently with the site investigation works, according to the PNAP No. 252 (ADV-21) Management Framework
for Disposal of Dredged/Excavated Sediment ) (Appendix 7.1 refers). No dredging works will be required for
the Project, and thus no marine-based sediment will be generated.
7.4.18
The timetable for the sediment sampling,
chemical / biological screening and the subsequent laboratory reporting is
summarised in Table 7.2 below.
Table 7.2 Timetable for Sediment Sampling
and Laboratory Testing
|
Task
Descriptions
|
Time
Period
|
|
Sediment sampling
|
April to June 2016
|
|
Tier II chemical
screening
|
April to July 2016
|
|
Tier III biological
screening
|
May to August 2016
|
|
Reporting
|
August to Sept 2016
|
7.4.19
Upon completion of the SI works, a review on the
sediment quality of the sediment sampling and testing works were conducted,
making reference to PNAP No. 252 (ADV-21) and memo issued by Development Bureau
※Control Measures for Management of Dredged/Excavated
Contaminated Sediment§ (ref: 0 in DEVB(W) 515/83/04) (Appendix 7.2 refers), to identify and characterize the
excavated sediment, estimate the quantity of sediment to be encountered in the
Project and propose transportation routings and handling/disposal
arrangements/methods to fulfill the requirements of ESB-296/2016.
7.4.20
The sediment sampling and testing works commenced
on 29th April 2016 which is within 3 years at the time of this EIA
Study. In addition to ground
condition remains unchanged, based on PNAP No. 252 (ADV-21) (para. 2), the sampling and testing
results obtained within the boundary of SHD (Section 7.4.26 to 7.4.29
refers) are therefore considered to be reliable and representable to the
underlying sediment condition for the assessment of waste management
implications associated with the sediment excavation under this EIA Study.
Details of the review on the sediment quality are discussed below.
Sediment Sampling Locations, Depth of Sampling and Sampling
Procedure
7.4.21
The nearest EPD＊s sediment monitoring station is
NS2 located within the North Western Water Control Zone. The latest available
sediment quality data from 2011 to 2015 are summarized in the Annual Marine Water
Quality Report 2015 published by EPD. Based on the EPD＊s annual report, the
measured concentrations of the parameters as listed in PNAP No. 252 (ADV-21)
were below the corresponding Lower Chemical Exceedance Level (LCEL).
7.4.22
As it is possible that the sediment
contamination level within the study area is Category M/H, a 200m x 200m
sampling grid arrangement was adopted to enable a more accurate estimation of
mud disposal volume, with reference to the memo issued by Development Bureau, ※Control Measures for Management of
Dredged/Excavated Contaminated Sediment§ (ref: 0 in DEVB(W) 515/83/04).
7.4.23
Based on the adopted sampling grid arrangement, sediment
sampling were conducted at 15 land-based locations to cover the proposed works
areas where sediment could potentially be encountered, i.e. the existing SHD, the
proposed SHO station and the proposed piling works for local access as shown in
Figure No. NEX1062/S/SHD/ACM/Z10/190.
For the remaining areas within the Scheme Boundary, either no excavation works
or only shallow excavation above the sediment layer and no excavation of
sediment is anticipated. The sediment sampling locations were conducted taken
into consideration the site constraints within the Scheme Boundary (e.g.
presence of existing structures / facilities / railway and impact to current operation
of SHD, TCL and AEL).
7.4.24
The land-based sediment samples collections were
conducted by means of dry rotary drilling method (i.e. without the use of
flushing medium). In some occasions, only potable water from nearby fire
hydrant via water adaptors supplied by the Water Supplies Department (WSD) was
used as drilling fluid when encountering of hard substrata or in difficult
cases prior to the encounter of sediment layer, no flushing medium was used
during the collection of sediment samples. Inspection pits in the size of
0.3x0.3m were excavated down by hand tools to 3m below ground level (m bgl) to
inspect for underground utilities. Drill rigs were then deployed to carry out
the drilling and sampling. Sediment was collected at depths
where marine deposits are firstly encountered and samples were generally taken
at that particular depth (i.e. immediately above the top of marine deposit),
0.9m down, 1.9m down, 2.9m down and then every 3m down to the borehole
termination depth. The depth of sediment sampling was terminated at least 1m
below the base of sediment. The as-built sampling locations are shown in Figure No. NEX1062/S/SHD/ACM/Z10/190.
7.4.25
Grab sediment sample was collected from EPD＊s
routine sediment monitoring station PS6 at Port Shelter (850234E, 820057N) on
22 June 2016 as the reference sediment sample. The grab sediment sample was
collected by closed grab sampler and was placed into new/pre-cleaned high
density polyethylene containers and wide mouth borosilicate glass bottles with
Teflon lined lids and sealed to prevent leakage.
Sediment Sampling and Testing Results
7.4.26
Chemical and biological screening of sediment
samples were carried out and each sample was tested for chemical screening according
to PNAP No. 252 (ADV-21).
7.4.27
A total of 53 samples were collected from the
land-based sampling locations and tested for chemical screening. The chemical
screening results are summarised in Table
7.3 with details provided in Appendix 7.3. The laboratory analytical reports for
chemical screening are provided in Appendix 7.5.
7.4.28
Based on the chemical screening results,
Category H sediments were identified in 2 samples at locations EDH14 and EDH15
with Zinc exceeded the UCEL but below 10 times the LCEL. Category M sediments were also found in 5
samples at sampling locations EDH04, EDH16 and EDH17 with Arsenic and/or Zinc
exceeded the LCEL but equal to or below the UCEL. The remaining samples were
identified as Category L sediment.
Table 7.3 Summary of Chemical
Screening Results
|
Category
|
Percentage
|
No. of
Samples
|
|
Category L (equal to or below LCEL)
|
86.8%
|
46
|
|
Category M (above LCEL but equal to or
below UCEL)
|
9.4%
|
5
|
|
Category H (above UCEL but equal to or below 10x LCEL )
|
3.8%
|
2
|
|
Category
H (above 10x LCEL)
|
0%
|
0
|
|
Total:
|
100%
|
53
|
7.4.29
Based on the chemical screening results, Tier
III biological screening was conducted on the 5 Category M sediment samples and
all the samples passed the screening. The results of the biological screening
are summarised in Table 7.4 with
details provided in Appendix
7.4. The laboratory analytical reports for
biological screening are provided in Appendix
7.6.
Table 7.4 Summary
of Biological Screening Results
|
Sampling ID
|
Sampling Depth (m)
|
Classification
|
Result of Biological Screening
|
|
EDH04
|
10.00-10.95
|
Category
M
|
Pass
|
|
16.00-16.95
|
Category
M
|
Pass
|
|
EDH16
|
12.00-12.95
|
Category
M
|
Pass
|
|
17.00-17.95
|
Category
M
|
Pass
|
|
EDH17
|
14.50-15.45
|
Category
M
|
Pass
|
Sediment Disposal Options
and Quantities
7.4.30
Based on the
screening results and the above findings, the disposal options for each of the
sediment samples were determined in accordance with the PNAP No. 252 (ADV-21).
The quantities of sediments to be generated under each disposal option is then
estimated with consideration of (i) the excavation extent and profiles for the proposed
SHO, Stage 1 to 4 SHD Replanning Works and the proposed piling works for local access,
(ii) the depths and thickness of the underlying sediment and (iii) the
determined disposal options of the sediment samples as based on the chemical
and biological screening results. The total volume of sediment generated is
estimated to be approximately 21,826 m3. Beneficial reuse will be considered
on site as far as practicable during the construction stage before the disposal
of excavated sediment. Based on
current estimation, the quantities for each disposal type are presented
in Table 7.5.
7.4.31
It should be
noted that no sediment samples were encountered in the sampling location EDH09.
It is assumed that no sediment would be encountered within the concerned
sampling grid in the quantities estimation.
Table 7.5 Estimated
Quantities of Sediment under each Disposal Option
|
Disposal Option
|
Corresponding
Category
|
Estimated In-situ Quantity(1)(2) (m3)
|
|
Stage 1 & SHO
|
Stage 2
|
Stage 3
|
Stage 4
|
|
Type 1 每 Open Sea Disposal
|
Category L Sediment
|
8,018
|
3,909
|
2,149
|
4,688
|
|
Type 1 每 Open Sea Disposal (Dedicated Sites) at
disposal site(s) allocated by MFC
|
Category M Sediment (passed the
biological screening)
|
493
|
879
|
166
|
660
|
|
Type 2 每 Confined Marine Disposal at
disposal site(s) allocated by MFC
|
Category H Sediment (does not require
biological screening)
|
263
|
0
|
51
|
550
|
|
Type 3 每 Special Treatment/ Disposal
|
Category
H Sediment (failed biological screening)
|
0
|
0
|
0
|
0
|
|
Sub-Total
|
8,774
|
4,788
|
2,366
|
5,898
|
|
Total
|
21,826
|
7.4.32
The sediment
would be disposed of at the designated marine disposal areas according to PNAP
No. 252 (ADV-21). The disposal
options for the excavated sediment should follow the procedures in PNAP No. 252
(ADV-21). The transportation routing and frequency for marine disposal to
designated disposal outlets (Table 7.6
refers) shall be agreed with EPD/CEDD during the construction phase of each
stage prior to marine disposal. The recommended mitigation
measures for marine disposal are discussed in Section 7.5. No adverse waste management implications are
anticipated if the recommended mitigation measures are implemented.
Operation Phase
7.4.33
During operation
of the Project, the major types of wastes generated include:
﹞
Chemical waste; and
﹞
Municipal solid waste.
Chemical Waste
7.4.34
Chemical wastes such as paints, lubricants and
used batteries may be generated during maintenance activities in station and
depot. This waste may pose
environmental, health and safety hazards. Measures
as stipulated in the Waste Disposal (Chemical
Waste) (general) Regulation and the Code
of Practice on the Packaging, Labelling and Storage of Chemical Wastes would
be strictly followed for the handling and disposal of chemical waste.
7.4.35 Should
any chemical waste be generated, the operator must register with EPD as a
chemical waste producer. The
chemical waste would be readily accepted for disposal of at the CWTC at Tsing Yi
or other licensed facilities. This chemical waste should be
collected periodically in drum-type containers by licensed chemical waste
collectors. With proper storage,
handling and disposal of this waste, no adverse environmental impact is
anticipated.
Municipal Solid Waste (MSW)
7.4.37
The maximum number of persons including staff and
commercial operators in SHO and Reprovisioned SHD during the operation phase of
the Project is estimated to be about 200.
Based on a generation rate of 0.65
kg per person per day, approximately 130kg of MSW (general
refuse) will be generated daily during the operation period. As the passengers are only transient
population and will not stay in SHO, and thus the quantities of MSW (general
refuse) generated from passengers are negligible.
7.4.38
For the MSW generated from maintenance activities, it is expected that small
to a few hundred kg per month will be generated during the operation period. Plastics, papers and other recyclable
wastes should be separated from general refuse and recycled as far as
possible. The remaining refuse would be collected by waste collectors
and disposed of at landfills.
Construction Phase
﹞
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.
7.5.2
Based on the waste management hierarchy, waste
reduction measures are recommended as follow to reduce impacts and costs arisen
from the Project. Recommendations
of good site practices and waste reduction measures have been stated in order
to achieve avoidance and minimization of waste generation in the
hierarchy.
Good Site Practices
7.5.3
Adverse impacts would not arise in 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 implementation of good
site practices, arrangements for waste collection and effective disposal to an
appropriate facility;
﹞
Training of site personnel in site
cleanliness, concepts of waste reduction, reuse and recycling, proper waste management and chemical waste handling procedures;
﹞
Provision of sufficient waste
reception/ disposal points, and regular collection of waste;
﹞
Adoption of appropriate
measures to minimise windblown litter and dust during transportation of waste
by either covering trucks or by transporting wastes in enclosed containers;
﹞
Provision of regular cleaning
and maintenance programme for drainage systems, sumps and oil interceptors;
﹞
Adoption of a recording system
for the amount of wastes generated, recycled and disposed (including the
disposal sites); and
﹞
Preparation
of Waste Management Plan (WMP), as part of the Environmental Management
Plan (EMP).
Waste Reduction Measures
7.5.4
Good management and control of construction site
activities / processes can minimise 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 are discussed as
follow:
﹞
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;
﹞
Recycle any unused chemicals or
those with remaining functional capacity;
﹞
Maximise the use of reusable
steel formwork to reduce the amount of C&D materials;
﹞
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 minimise the amount of waste generated; and
﹞
Minimize over ordering and
wastage through careful planning during purchasing of construction materials.
7.5.5
In addition to the above measures, other
specific mitigation measures are recommended below to minimise environmental
impacts during handling, transportation and disposal of wastes.
Construction and Demolition Materials
7.5.6
The C&D materials generated from site
clearance, excavation works, and construction of station should be sorted
on-site into inert C&D materials (that is, public fill) and C&D waste.
To minimise 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. A suitable area should be designated within the site for temporary
stockpiling of C&D materials and to facilitate the sorting process. Within
the stockpile areas, the following measures should be taken to control
potential environmental impacts or nuisance:
﹞
Proper handling and storage of
waste such as soil by means of covers and/or water spraying system to minimise
the potential environmental impact and to prevent materials from wind-blown or
being washed away;
﹞
Covering materials during heavy
rainfall;
﹞
Locating stockpiles to minimise
potential visual impacts;
﹞
Minimising land intake of
stockpile areas as far as possible;
﹞
Adopting GPS or equivalent
system for tracking and monitoring of all dump trucks engaged for the Project
in recording their travel routings and parking locations to prohibit illegal
dumping and landfilling of C&D materials; and
﹞
keeping record and analysis of
data collected by GPS or equivalent system related to travel routings and
parking locations of dump trucks engaged on site.
General Refuse
7.5.7
General refuse should be stored in enclosed bins
or compaction units separate from C&D materials and chemical waste. A reputable waste collector should be
employed by the contractor to remove general refuse from the site, separately
from C&D materials and chemical wastes. An enclosed and covered area
is preferred to reduce the occurrence of 'wind blown'
light materials.
7.5.8
The recyclable component of general refuse, such
as aluminium cans, paper and cleansed plastic containers shall be separated
from other waste. 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.
7.5.9
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.
Chemical Wastes
7.5.10
If chemical wastes were to be produced at the
construction site, the Contractor would 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.
7.5.11
Appropriate containers with proper labels should
be used for storage of chemical wastes.
Chemical wastes should be collected and delivered to designated outlet
by a licensed collector. Chemical
wastes (e.g. spent lubricant oil) should be recycled at an appropriate facility
as far as possible, while the chemical waste that cannot be recycled should be
disposed of at either the CWTC, or another licensed facility, in accordance
with the Waste Disposal (Chemical Waste) (General) Regulation.
7.5.12
Any unused chemicals or those with remaining
functional capacity should be collected for reuse as far as practicable.
Sediments
7.5.14 Requirements of the Air Pollution Ordinance (Construction Dust) Regulation, where
relevant, shall be adhered to during excavation, transportation and disposal of
the sediment.
7.5.15 In order to minimise 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.
7.5.16 For off-site disposal, the basic requirements and
procedures specified under PNAP No. 252 (ADV-21) shall be followed. Marine Fill Committee (MFC) of CEDD is managing
the disposal facilities in Hong Kong for the excavated sediment,
while EPD is the authority of issuing marine
dumping permit under the Dumping at Sea Ordinance (DASO).
7.5.17
For the purpose
of site allocation and application of marine dumping permit and if considered
necessary by EPD (Marine Dumping Section), a separate SSTP shall be submitted
to EPD for agreement under DASO.
Additional SI works, based on the SSTP, shall then be carried out in
order to confirm the disposal arrangements of the excavated sediment. A Sediment Quality Report (SQR),
reporting the chemical and biological screening results and the estimated
quantities of sediment under different disposal options, shall then be
submitted to EPD for agreement under DASO.
7.5.18
To ensure
disposal space is allocated for the Project, the Project Proponent should be
responsible for obtaining agreement from MFC on the allocation of the disposal
site. The contractor(s), on the other hand, should be responsible for the application
of the marine dumping permit under DASO from EPD for the sediment disposal.
7.5.19
The excavated
sediments is expected to be loaded onto the barge at public barging point of
which the exact location will be determined by the contractor(s) and agreed by
EPD/CEDD and transported to the designated disposal sites allocated by
MFC. The excavated sediment would
be disposed of according to its determined disposal options and PNAP No. 252
(ADV-21).
7.5.20
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).
7.5.21
In order to
minimise 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.
7.5.22
The barge
transporting the sediments to the designated disposal sites shall be equipped
with tight fitting seals to prevent leakage and shall not be filled to a level
that would cause overflow of materials or laden water during loading or
transportation. In addition, monitoring of the barge loading shall
be conducted to ensure that loss of material does not take place during
transportation. Transport barges or vessels shall be equipped with automatic
self-monitoring devices as specified by the DEP.
Operational Phase
Chemical Wastes
7.5.23
The requirements given in the Code
of Practice on the Packaging, Labelling and Storage of Chemical Wastes should
be followed in handling of chemical waste as in construction phase. A
trip-ticket system would be adopted by the Project Proponent to monitor
disposal of chemical waste.
7.5.24
Chemical waste shall be disposed of at
appropriate facility such as the CWTC by licensed collectors. It is expected quantities of chemical
wastes to be generated from the SHO and the Reprovisioned SHD would be of
similar magnitude as current operation of SHD, i.e. about small to a few hundred
litres per month.
Municipal Solid Wastes
7.5.25 The
MSW generated from SHO and Reprovisioned SHD will follow the current practice
of waste management as adopted in existing SHD operation. Designated areas will be assigned for
proper storage and collection of MSW generated on site. Segregation of MSW will
be conducted on site to allow for maximization of recycling opportunities. It is recommended to place clearly
labelled recycling bins at designated locations which could be accessed
conveniently. A
reputable waste collector should be employed to remove MSW regularly to
minimize potential impacts arising from storage and collection of MSW.
7.5.26
Table 7.6 provides a summary of the various
waste types likely to be generated during the construction and operation of the
Project, together with the recommended handling and disposal methods.
Table 7.6 Waste
Arising, Waste Handling Procedures and Disposal Outlets
|
Waste
Material Type
|
Generated
From
|
Materials
Generated
|
Total
Quantity Generated
|
Handling
Methods/
Reuse
|
Disposal
Outlet
|
|
C&D Materials
|
Construction
Phase:
Excavation, Demolition
Works, Site Formation and Construction
of Station.
|
Inert C&D
materials 每 Rock, Soft Materials and Artificial Hard Materials
|
1,319,370m3
|
﹞ Segregation
from non-inert C&D materials during stockpiling
﹞ Stockpile area
(if required) should be well managed with covers and water spraying system
|
﹞ Public Fill
Reception Facilities areas or reclamation sites
|
|
Non-inert C&D
materials 每 Vegetation, Timber, Papers and Plastics
|
18,200
m3
|
﹞ Segregation
from inert C&D materials during stockpiling
﹞ Reusable materials should be separated and recycled as far as
practicable
|
Designated Landfill
Site to be agreed with EPD/CEDD
|
|
General Refuse
|
Construction Phase: Workforce
|
Food waste, plastic,
aluminium cans, waste papers etc.
|
Construction Phase: 228 kg/day
|
﹞ Provide on-site
collection points together with recycling bins
﹞ Collected by reputable waste collectors
|
Designated Landfill
Site to be agreed with EPD/CEDD
|
|
Chemical Waste
|
Construction and operation phase:
Maint-enance and Operation of Equipments and Machineries
|
Oils and grease
hydraulic fluids, paints, solvents, cleaners etc.
|
Construction Phase: Small to a Few hundred litres
per month
Operation Phase: Small to a Few hundreds litres
per month
|
﹞ Store in
compatible containers in designated area on site
﹞
To be collected and recycled by licensed collectors
|
Chemical
Waste Treatment Centre (CWTC) or other
licensed facilities
|
|
Municipal Solid Waste
|
Operation
Phase: Maint-enance and Operation of Equipments and Machineries; Staff and
commercial operators
|
Metal, used
fluorescent tubes(1), used welding rods, cleansing materials,
discarded electronic equipment, food waste, plastic
waste,
, papers waste
and office waste etc.
|
Operation Phase: Small to Few hundreds kg per
month generated from maintenance activities; and 130kg/day generated from
staff and commercial operators.
|
﹞ Provide on-site
collection points together with recycling bins
﹞ Collected by reputable waste collectors
|
Refuse transfer station or recycling facilities
|
|
Land-based Sediments
|
Piling
works and excavation works for the proposed
Replanning Works within the existing SHD and the SHO station construction.
|
Category
L Sediment
|
18,764 m3
|
﹞ Beneficial
reuse on site as far as practicable
﹞ Type 1 - Open
sea disposal at marine disposal site(s) allocated by by MFC.
|
Final disposal site shall be determined by
MFC;
typically South Cheung Chau / East of Ninepin
|
|
Category
M Sediment (passed Tier III - biological screening)
|
2,198 m3
|
﹞ Beneficial
reuse on site as far as practicable
﹞ Type
1 - Open sea disposal (dedicated site) at marine disposal site(s) allocated by
MFC.
|
Final disposal
site shall be determined by MFC; typically South Cheung Chau / East of
Ninepin
|
|
Category H Sediment
(does not require the Tier III biological screening))
|
864 m3
|
﹞ Beneficial
reuse on site as far as practicable
﹞ Type
2 -Confined marine disposal at marine disposal site(s) allocated by MFC.
|
Final disposal
shall be determined by MFC; typically East Sha Chau
|
7.6
Evaluation of Residual
Environmental Impacts
7.6.1
With the implementation of the recommended
mitigation measures for the handling, transportation and disposal of the
identified waste arising, adverse residual impact is not expected to occur
during the construction and operation of the Project.
7.7
Environmental
Monitoring and Audit Requirement
Construction Phase
7.7.1
During the construction period, it is the Contractor＊s
responsibility to ensure that all waste produced during the construction of the
Project are handled, stored and disposed of in accordance with good waste
management practices, relevant legislation and waste management guidelines.
7.7.2
Waste materials generated during construction
activities, such as C&D materials, are recommended to be audited at regular
intervals to ensure that proper storage, transportation and disposal practices
are being implemented. This would
ensure the waste generated would be properly disposed of. The Contractor would be responsible for
the implementation of any mitigation measures to minimise waste or mitigate
problems arisen from waste materials.
7.7.3
A WMP should be prepared and submitted to the
Engineer for approval. The recommended
mitigation measures should form the basis of the WMP.
Operational Phase
7.7.4
With the implementation of good waste management
practices, no adverse environmental impacts is expect to arise, and therefore
waste monitoring and audit programme during the operation phase is not required.
7.8.1
Waste types
generated by the construction of this Project are likely to include C&D
materials (from excavation and piling works, demolitions of existing structures
and site formation), sediment; chemical waste from maintenance of construction
plant and equipment and general refuse.
Provided that these wastes are handled, transported and disposed of according
to the recommended good site practices, adverse environmental impacts are not
expected during the construction phase.
7.8.2
The total volume
of excavated sediment generated from the proposed SHO, Stage 1 to 4 of the SHD Replanning
Works and the proposed piling works for local access is estimated to be
approximately 21,826 m3. Based on the results of the chemical
and biological screening, approximately 18,764 m3 of
sediment is suitable for Type 1 每 Open Sea Disposal, 2,198 m3 of
sediment is suitable for Type 1 每 Open Sea Disposal (Dedicated Sites) and 864
m3 of sediment requires Type 2 每 Confined Marine Disposal in
accordance with PNAP No. 252 (ADV-21). With the implementation of the
recommended mitigation measures detailed in Sections 7.5 and
in accordance with the requirements of PNAP No. 252 (ADV-21), no adverse
environment impacts would be expected from excavation, transportation and
disposal of marine sediment.
7.8.3
The main waste types generated during the
operation of the SHO and Reprovisioned SHD would be chemical waste and MSW from
maintenance activities, commercial operators and staff. The handling, collection, transportation
and disposal practices of the identified waste generated should follow the
current practices at other operating railway lines. It is anticipated that no adverse
impacts would arise if the mitigation measures are strictly followed.