6
waste
management implications
6.2.1
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 (EIAO-TM).
6.2.2
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.132) (PHMSO) and Public Cleansing and Prevention of
Nuisances Regulation (Cap. 132BK);
﹞
Dumping at Sea Ordinance (Cap. 466); and
﹞
Buildings Ordinance (Cap 123).
Waste Disposal Ordinance (Cap. 354)
6.2.3
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 should be disposed of
at designated waste disposal facilities licensed by the Environmental
Protection Department (EPD).
Waste Disposal (Chemical Waste) (General)
Regulation (Cap.354C)
6.2.4
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)
6.2.5
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)
6.2.6
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 PFRFs are required to obtain Dumping Licences. The licences are issued
by CEDD under delegated authority from the Director of Lands.
6.2.7
Individual licences
and windscreen stickers are issued for each vehicle involved. Under the licence
conditions, PFRFs 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 (PFC)
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 (Cap. 132) and Public Cleansing and Prevention of Nuisances
Regulation (Cap.132BK)
6.2.8
The PHMSO and 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)
6.2.9
The Dumping at Sea Ordinance
(DASO) 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:
﹞
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.
6.2.10
Marine disposal of any
dredged/excavated sediment is subject to control under the DASO. 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 - 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)
6.2.11
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
6.2.12
Environmental guidelines that
are related to waste 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.
6.2.13
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.
6.2.14
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 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.
6.2.15
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; 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.
6.2.16
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.
6.2.17
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.
6.3
Identification and Evaluation of Wastes
Implications
Assessment Methodology
6.3.1
The criteria and methodology of
assessing potential waste management implications during the construction and
operation phases follows Annexes 7 and 15 of the EIAO-TM, respectively. Appendix E of the EIA Study Brief (No.
ESB-332/2020) also specifies the requirements for assessment of waste
management implications.
Assessment approaches are discussed below:
﹞
Identification and estimation
of the types, quantities, qualities and timing of the wastes generated;
﹞
Evaluation of opportunities for
waste reduction, re-use and recycling;
﹞
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 discharges and
public transport;
﹞
Assessment of impacts on the
capacity of waste collection, transfer and disposal facilities; and
﹞
Identification of practicable
means of avoiding illegal dumping and landfilling.
Construction Phase
6.3.2
The construction activities to
be carried out for the Project would generate a variety of wastes that can be
divided into distinct categories based on their composition and ultimate method
of disposal. The following wastes types are anticipated to be generated:
﹞
Construction and demolition
(C&D) materials;
﹞
General refuse;
﹞
Chemical wastes; and
﹞
Land-based and river-based
sediments.
Construction and
Demolition Materials
6.3.3
C&D materials would be
generated from excavation, demolition
works, site formation, piling works,
and construction of facilities and stations.
These C&D materials comprise both inert (e.g.
rocks, soil, broken concrete, building debris) and non-inert components (e.g. vegetation and wood).
6.3.4
In view of site constraints,
scale and nature of the Project, the available schemes for construction of the
Project are limited, generation of C&D materials has been minimized as far
as possible with the following measures taken in consideration:
﹞
Minimal interference with
existing structures as far as possible to reduce the quantity of demolition
materials;
﹞
Maximisation in the use of
prefabricated materials where possible; and
﹞
Reuse of excavated materials
where possible.
6.3.5
Based on preliminary design
information, it was estimated that the total volume of C&D materials to be
approximately 97,202 m3 of
inert materials and approximately 27,930 m3 of non-inert materials.
6.3.6
A summary of inert and
non-inert C&D materials generated during construction phase is shown in Table 6.1. 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. As such, only small stockpile area(s)
could be 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. Surplus inert
C&D materials generated from the Project would be delivered to the Tuen Mun Area
38 Fill Bank which is being operated by CEDD.
Table
6.1 Summary
of Inert and non-inert C&D Materials
Quantities Generated
|
Works
|
Construc-tion Period
|
Approx. Quantities of Waste To be Generated
(m3)
|
|
Soft Inert Materials(1)
|
Grade III Rock(2)
|
Artificial
Hard Material(3)
|
Non-inert
C&D Material(4)
|
|
A16, Viaduct & TRB
|
2023 每 2027
|
55,776
|
3,207
|
15,340
|
23,640
|
|
TMS
|
2024 每 2026
|
7,009
|
350
|
15,520
|
4,290
|
|
Total Generation
|
62,785
|
3,557
|
30,860
|
27,930
|
|
Disposal Outlet
|
Tuen Mun Area 38 Fill Bank or reclamation sites
|
Tuen Mun Area 38 Fill Bank or reclamation sites
|
Tuen Mun Area 38 Fill Bank or reclamation sites
|
Designated Landfill Site such as WENT
landfill to be agreed with EPD/CEDD
|
Notes:
(1) ※Soft Inert Materials§ include fill, alluvium, colluvium,
Grade IV to Grade VI (Granite) and Grade IV to Grade VI (Volcanic).
(2) ※Grade III Rock§ includes Grade III granite rock
and Grade III volcanic rock.
(3) ※Artificial hard material§ includes, but not
limited to, asphalt, broken concrete, bitumen and granular materials, etc.
(4) ※Non-inert C&D material§ includes, but not
limited to, bamboo, timber, paper and plastic, etc.
6.3.7
Non-inert C&D materials generated
would be reused and recycled as much as possible before disposal of at
designated landfill site (e.g. WENT landfill) to be agreed with EPD/CEDD.
6.3.8
The number of construction vehicle involved in transporting C&D
materials/land-based sediment to the disposal outlets is estimated to be about
12 nos. per day, 8am to 6pm, throughout the construction phase, based on the
current engineering design. Upon
leaving the construction site, construction vehicles will enter Wu King Road,
Wu Chui Road, Wong Chu Road, Lung Fu Road / Lung Mun Road via local roads (Appendix 6.8 refers) and ultimately to the
designated disposal outlets (Table 6.1
refers) as agreed with EPD/CEDD during construction phase. 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 6.4.
General Refuse
6.3.9
During the construction period,
the workforce would generate refuse comprising food scraps, waste paper, empty
containers, etc. Proper disposal, storage
of general refuse on-site and regular cleaning of waste containers are crucial
in preventing environmental impacts such as water pollution, odour nuisance, visual impacts, vermin and pests
infestation.
6.3.10
The maximum number of
construction workers to be employed on the Project is estimated to be about 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.
6.3.11
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 designated landfills
(e.g. WENT landfill) to be agreed with EPD/CEDD.
6.3.12
With proper implementation of
waste management practices as detailed in Section
6.4, it is anticipated that the secondary environmental impacts from
collection and handling of general refuse would be minimal.
Chemical Waste
6.3.13
The maintenance and servicing
of construction plant and equipment may possibly generate a variety of chemical
wastes, for instance, cleaning fluids, solvents, lubrication oil, waste fuel,
etc.
6.3.14
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.
6.3.15
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
6.4. Provided that the
handling, storage and disposal of chemical wastes are in accordance with these
requirements, adverse environmental impacts are not expected.
Excavated
Sediments
6.3.16
The Project is situated on
reclaimed land and Tuen Mun River. Based on previous ground
investigation (GI) records, land-based and river-based
sediment is expected
within the Project area and maybe encountered during the piling and excavation
works associated with the construction of the piers and
columns for the viaducts and stations.
6.3.17
Pursuant to Appendix E, 3(i) of
ESB-332/2020, a Sediment Sampling and Testing Plan (SSTP) was prepared with
reference to PNAP No. 252 (ADV-21) and
submitted to EPD for approval. This Plan details the ranges of parameters to
be analysed; the number, type and methods of
sampling; sample preservation; chemical and biological laboratory test methods
to be used.
6.3.18
The nearest EPD＊s sediment
monitoring station is NS5 located within the Tuen Mun Typhoon Shelter. The
latest available sediment quality data from 2016 to 2020 are summarised in the Annual Marine Water Quality Report 2020
published by EPD. Based on the EPD＊s annual report, the measured concentrations
of the parameters, except for silver, zinc, arsenic and lead, as listed in PNAP
No. 252 (ADV-21) were below the corresponding Lower Chemical Exceedance
Level (LCEL). For zinc, arsenic and
lead, the highest levels measured (zinc: 260 mg/kg, arsenic: 14 mg/kg and lead:
89 mg/kg) were above the corresponding LCEL but below the UCEL. For silver, the
arithmetic mean value (1.4 mg/kg) had exceeded the LCEL but below the UCEL
and the highest level measured (9.7 mg/kg) was above the UCEL.
6.3.19
As contaminants exceeding the
LCEL / UCEL were identified in the EPD monitoring data, a 200m x 200m sampling
grid arrangement with reference to the memo ※Control Measures for Management of Dredged/Excavated Contaminated
Sediment§ issued by Development Bureau (ref: 0 in DEVB(W) 515/83/04) (Appendix
6.2 refers) would be suffice.
However, in order to refine the sediment profile and quantities
estimation, a more stringent 100 x 100m sampling grid arrangement, as recommended
in PNAP No. 252 (ADV-21) for expected high sediment contamination level,
was proposed.
6.3.20
Based on the adopted sampling
grid arrangement, a total of 32 sampling locations (16 land-based and 16
river-based) were proposed according to the proposed alignment options during
the course of the study. 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 SSTP as agreed by the EPD on 29
January 2021 are enclosed in Appendix 6.1. After the
agreement on the SSTP sought, the preferred alignment had been selected for the
EIA study. A review of validity of
SSTP has been conducted and it was confirmed that the proposed sediment
sampling locations remain valid for the preferred alignment. The proposed sampling locations and the
preferred alignment are shown in Figure Nos. C1502/C/TME/ACM/M54/101 -
102.
6.3.21
Site investigation (SI) was
conducted between March and August 2021 according to the agreed SSTP. The
sampling works were conducted by Tysan Foundation
Limited and Lam Geotechnical Limited, while the laboratory testing was carried
out by ALS Technichem (HK) Pty. Ltd., which is an
HOKLAS accredited laboratory.
6.3.22
The sediment sampling locations
were conducted taken into consideration the site constraints within the Scheme
Boundary (e.g. presence of existing road traffic / structures / facilities /
utilities). It should be noted that minor
changes were made to the sampling location IDs after EPD＊s agreement on the
SSTP. The changes are shown in Table 6.2 below and are adopted in
the remaining part of this section. The as-built sampling
locations are shown in Figure Nos. C1502/C/TME/ACM/M54/103 -
104.
Table
6.2 Changes in
Sampling Location ID
|
Sampling Location ID Proposed in SSTP
|
As-built
Sampling Location ID
|
|
Land-based
|
|
1530-TME-EDH203
|
1530-TME-EDH501
|
|
1530-TME-EDH204
|
1530-TME-EDH502
|
|
1530-TME-EDH205(P)
|
1530-TME-EDH503(P)
|
|
1530-TME-EDH306
|
1530-TME-EDH504
|
|
1530-TME-EDH206
|
1530-TME-EDH505
|
|
1530-TME-EDH207
|
1530-TME-EDH506
|
|
1530-TME-EDH315
|
1530-TME-EDH507
|
|
1530-TME-EDH116
|
1530-TME-EDH508
|
|
1530-TME-EDH210(P)
|
1530-TME-EDH509
|
|
1530-TME-EDH227(P)
|
1530-TME-EDH510(P)
|
|
1530-TME-EDH213
|
1530-TME-EDH511
|
|
1530-TME-EDH215
|
1530-TME-EDH512
|
|
1530-TME-EDH117
|
1530-TME-EDH513
|
|
River-based
|
|
1530-TME-MEDH203
|
1530-TME-MEDH601
|
|
1530-TME-MEDH117
|
1530-TME-MEDH602
|
|
1530-TME-MEDH105
|
1530-TME-MEDH603
|
|
1530-TME-MEDH106
|
1530-TME-MEDH604
|
|
1530-TME-MEDH107
|
1530-TME-MEDH605
|
|
1530-TME-MEDH108
|
1530-TME-MEDH606
|
|
1530-TME-MEDH109
|
1530-TME-MEDH607A
|
|
1530-TME-MEDH110
|
1530-TME-MEDH608
|
|
1530-TME-MEDH111
|
1530-TME-MEDH609
|
|
1530-TME-MEDH112
|
1530-TME-MEDH610
|
|
1530-TME-MEDH113
|
1530-TME-MEDH611A
|
|
1530-TME-MEDH114
|
1530-TME-MEDH612
|
|
1530-TME-MEDH115
|
1530-TME-MEDH613
|
|
1530-TME-MEDH116
|
1530-TME-MEDH614
|
6.3.23
The land-based sediment
sampling was carried out using borehole drilling method. Sediment was collected using U100 sampler at depths where marine deposits are firstly encountered and samples
were generally taken at that particular depth (i.e. top level 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.
6.3.24
The river-based sediment
sampling was carried out by means of grab sampling using closed grab sampler at
the riverbed level and borehole drilling method for the vertical sediment
profiles below. The sediment below the riverbed level
was collected using U100 sampler at depths where marine deposits were firstly
encountered and samples were generally taken at that particular depth (i.e. top
level 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.
6.3.25
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 6.2 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-332/2020.
6.3.26
Grab sediment sample was
collected from EPD＊s routine sediment monitoring station PS6 at Port Shelter
(850234E, 820057N) on 14 April 2021 as the reference sediment sample using
closed grab sampler.
Sediment
Sampling and Testing Results
6.3.27
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).
6.3.28
Of the 32 sampling locations,
10 sampling locations (viz. 1530-TME-EDH506, 1530-TME-EDH109(P), 1530-TME-EDH508,
1530-TME-EDH513, 1530-TME-MEDH101, 1530-TME-MEDH102, 1530-TME-MEDH601,
1530-TME-MEDH607A, 1530-TME-MEDH610 and 1530-TME-MEDH611A) did not encounter
sediment and as such, no sediment samples were collected and tested from these
locations.
6.3.29
A total of 56 samples were
collected from the remaining 22 land-based and river-based sampling locations
and tested for chemical screening. The chemical screening results are summarised in Table
6.3 with details provided in Appendix 6.3. The laboratory analytical reports for
chemical screening are provided in Appendix 6.5.
6.3.30
Based on the chemical screening
results, Category H sediments were identified in 5 samples at sampling
locations 1530-TME-EDH501, 1530-TME-EDH505, 1530-TME-EDH114, 1530-TME-MEDH613
and 1530-TME-MEDH614 with lead / zinc exceeded the UCEL but below 10 times the
LCEL. Category M sediments were
also found in 6 samples at sampling locations 1530-TME-EDH504, 1530-TME-EDH505,
1530-TME-EDH507, 1530-TME-MEDH613 and 1530-TME-MEDH614 with arsenic / copper /
lead / low molecular weight polycyclic aromatic hydrocarbons (LMW PAHs)
exceeded the LCEL but equal to or below the UCEL. The remaining samples were
identified as Category L sediment.
Table
6.3 Summary of
Chemical Screening Results
|
Category
|
Percentage
|
No. of Samples
|
|
Category
L (equal to or below LCEL)
|
80.4%
|
45
|
|
Category
M (above LCEL but equal to or below UCEL)
|
10.7%
|
6
|
|
Category
H (above UCEL but equal to or below 10x LCEL)
|
8.9%
|
5
|
|
Category H (above 10x
LCEL)
|
0%
|
0
|
|
Total:
|
100%
|
56
|
6.3.31
Based on the chemical screening
results, Tier III biological screening was conducted on the 6 Category M
sediment samples and all the samples passed the screening. The results of the
biological screening are summarised in Table 6.4 with details provided in Appendix 6.4. The laboratory
analytical reports for biological screening are provided in Appendix 6.6.
Table 6.4 Summary of Biological
Screening Results
|
Sampling ID
|
Sampling
Depth (m bgl)
|
Classification
|
Result of Biological Screening
|
|
1530-TME-EDH504
|
15.90
每 16.90
|
Category
M
|
Pass
|
|
1530-TME-EDH505
|
11.00
每 12.00
|
Category
M
|
Pass
|
|
1530-TME-EDH507
|
17.10
每 18.10
|
Category
M
|
Pass
|
|
1530-TME-EDH507
|
19.10 每 20.10
|
Category
M
|
Pass
|
|
1530-TME-MEDH613
|
1.00 每 1.95
|
Category
M
|
Pass
|
|
1530-TME-MEDH614
|
0.50 每 0.95
|
Category
M
|
Pass
|
6.3.32
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 proposed piling works
for the viaduct and stations, (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 2,840 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 6.5. Detailed
calculation of excavated sediment quantities and assumptions are presented in Appendix 6.7.
6.3.33
It
should be noted that no sediment were encountered in sampling locations
1530-TME-EDH109(P), 1530-TME-EDH506, 1530-TME-EDH508, 1530-TME-EDH513,
1530-TME-MEDH101, 1530-TME-MEDH102, 1530-TME-MEDH601, 1530-TME-MEDH607A,
1530-TME-MEDH610 and 1530-TME-MEDH611A. It is assumed that no sediment would be
encountered within the concerned sampling grid in the quantity estimation.
Table 6.5 Estimated Quantities
of Sediment under each Disposal Option
|
Disposal Option
|
Corresponding Category
|
Estimated In-situ Quantity(1),(2) (m3)
|
|
Type 1 每 Open Sea Disposal
|
Category L Sediment
|
2,088
|
|
Type 1 每 Open Sea Disposal (Dedicated
Sites) at disposal site(s) allocated by MFC
|
Category M Sediment (passed the
biological screening)
|
433
|
|
Type 2 每 Confined Marine Disposal at
disposal site(s) allocated by MFC
|
Category H Sediment (does not require
biological screening)
|
319
|
|
Type 3 每 Special Treatment/ Disposal
|
Category H Sediment (failed
biological screening)
|
0
|
|
Total
|
2,840
|
6.3.34
The SSTP, testing results and
disposal option presented above are to fulfill the EIA Study under the EIAO.
Separate submissions of SSTP and Sediment Quality Report (SQR) for the
application of dumping permit under the DASO should be submitted to Marine
Dumping Control Section of EPD in accordance with PNAP No. 252 (ADV-21).
6.3.35
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 shall be agreed
with EPD/CEDD during the construction phase prior to marine disposal. The recommended mitigation measures for marine
disposal are discussed in Section 6.4. No adverse waste management implications
are anticipated if the recommended mitigation measures are implemented.
Operation Phase
6.3.36
During
operation of the Project, the major types of wastes generated include:
﹞ Chemical
waste; and
﹞ General
refuse.
Chemical Waste
6.3.37
Chemical wastes such as
cleaning fluids, solvents, lubrication oil and waste fuel may be generated
during maintenance activities in stations.
This waste may pose environmental, health and safety hazards if not
stored and disposed of in an appropriate manner. 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.
6.3.38
For the chemical waste
generated from maintenance activities, it is difficult to quantify the amount of chemical waste as it would
depend on the maintenance/housekeeping requirements. Though, in view
of the small project scale, it is anticipated that the quantity of chemical
waste during operation period would be small
to in the order of a few hundred litres per
month. 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.
General Refuse
6.3.40
The maximum number of persons
including staff and commercial operators during the operation phase of the
Project is estimated to be about 415, subject to operational need in the
future. Based on a generation rate of 0.65 kg per person per day, approximately
270 kg of general refuse will be generated daily during the operation period.
As the passengers are only transient population and will not stay in the
stations, and thus the quantities of general refuse generated from passengers
are negligible.
6.3.41
Plastics, papers and other
recyclable wastes should be separated from general refuse and recycled at
respective recycling facilities as far as possible. The remaining refuse would be collected
by waste collectors and disposed of at refuse transfer stations .
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.
6.4.2
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
6.4.3
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), and submission of WMP to the Engineer of the Project for approval.
Waste Reduction
Measures
6.4.4
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.
6.4.5
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
6.4.6
The C&D materials generated
from demolition works, site clearance, excavation works, and construction of
viaduct and stations should be sorted on-site into inert C&D materials
(i.e. 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
6.4.7
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.
6.4.8
The recyclable component of
general refuse, such as aluminium cans, paper and
cleansed plastic containers should 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.
6.4.9
The Contractor should 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 should also be provided in the sites as reminders.
Chemical Wastes
6.4.10
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.
6.4.11
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.
6.4.12
Any unused chemicals or those
with remaining functional capacity should be collected for reuse as far as
practicable.
Sediments
6.4.14
Requirements
of the Air Pollution Ordinance
(Construction Dust) Regulation, where relevant, should be adhered to during
excavation, transportation and disposal of the sediment.
6.4.15
In
order to minimise the exposure to contaminated materials, workers should, if
necessary, wear appropriate personal protective equipments
(PPE) when handling contaminated sediments. Adequate washing and cleaning facilities
should also be provided on site.
6.4.16
For
off-site disposal, the basic requirements and procedures specified under PNAP
No. 252 (ADV-21) should 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 DASO.
6.4.17
For
the purpose of site allocation and application of marine dumping permit and if
considered necessary by EPD (Marine Dumping Section), a separate SSTP should be
submitted to EPD for agreement under DASO.
Additional SI works, based on the SSTP, should 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, should then be
submitted to EPD for agreement under DASO.
6.4.18
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.
6.4.19
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).
6.4.20
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
placed on surface 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).
6.4.21
In
order to minimise the potential odour
/ dust emissions during excavation and transportation of the sediment, the
excavated sediments should be wetted during excavation / material handling and
should be properly covered when placed on trucks or barges. Loading of the excavated sediment to the
barge should be controlled to avoid splashing and overflowing of the sediment
slurry to the surrounding water.
6.4.22
The
barge transporting the sediments to the designated disposal sites shall be
equipped with tight fitting seals to prevent leakage and should 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 should be conducted to ensure that loss of material
does not take place during transportation. Transport barges or vessels should
be equipped with automatic self-monitoring devices as specified by the DEP.
Operational Phase
Chemical Wastes
6.4.23
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.
6.4.24
Non-recyclable chemical waste
should be disposed of at appropriate facility like CWTC by licensed
collectors. Recyclable chemical
waste should be collected and transported off-site by licensed collectors.
General Refuse
6.4.25
Designated areas will be assigned
for proper storage and collection of general refuse generated on site. A
reputable waste collector should be employed to remove general refuse regularly
to minimize potential impacts arising from storage and collection of general
refuse. Recycling bins would be provided to staff and passengers to separate
recyclable component of general refuse. Posters and leaflets advising on the
use of the bins would also be provided as reminders.
6.4.26
Table 6.6 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 6.6 Waste Arising, Waste Handling Procedures and Disposal Outlets
|
Waste Material Type
|
Generated From
|
Materials Generated
|
Total Quantity Generated
|
Handling Methods/
Reuse
|
Disposal Outlet, Tentative Routing and Frequency(1)
|
|
C&D Materials
|
Construction Phase: Excavation, demolition works, site formation, piling works, and
construction of viaduct and stations.
|
Inert
C&D materials 每 rock, soil, broken concrete, building debris, etc.
|
97,202m3
|
﹞ Segregation
from inert C&D materials during stockpiling
﹞ Stockpile
area (if required) should be well managed with covers and water spraying
system
|
Inert
C&D materials would be delivered to Tuen Mun Area 38 Fill Bank or
reclamation sites by approx. 9 dump trucks per day through Wu King Road, Wu
Chui Road, Lung Fu Road / Lung Mun Road.
|
|
Non-inert
C&D materials 每 vegetation, wood, etc.
|
27,930 m3
|
﹞ Segregation
from non-inert C&D materials during stockpiling
﹞ Reusable
materials should be separated and recycled as far as practicable
|
Dispose to
Designated Landfill Site such as WENT landfill to be agreed with EPD/CEDD by
approx. 3 dump trucks per day through Wu King Road, Wu Chui Road, Lung Fu
Road / Lung Mun Road.
|
|
General Refuse
|
Construction
Phase: Workforce
Operation
Phase:
Staff
and commercial operators; maintenance and operation of equipment and
machineries
|
Construction
Phase:
Food scraps, waste paper, empty containers, etc.
Operation
Phase:
Food
waste, paper, plastic and office waste, used fluorescent tubes(2), cleansing materials, etc.
|
Construction Phase:
228 kg/day
Operation Phase: 270
kg/day
|
﹞
Provide on-site collection points
together with recycling bins
﹞
To be collected and recycled by reputable
waste collectors
|
Construction
Phase: Dispose to Designated Landfill Site
such as WENT landfill to be agreed with EPD/CEDD by approx. 1 dump trucks per
day through Wu King Road, Wu Chui Road, Lung Fu Road / Lung Mun Road.
Operation
Phase:
Refuse transfer
station or recycling facilities, routing to be determined by the waste
collectors.
|
|
Chemical Waste
|
Construction and Operation Phase:
Maintenance
and servicing of construction plant and equipment
|
Cleaning fluids,
solvents, lubrication oil, waste fuel, etc.
|
Construction and
Operation Phase:
Small to a few hundred litres per month
|
﹞ Store
in compatible containers in designated area on site
﹞ To
be collected and recycled by licensed collectors
|
Dispose
to Chemical Waste Treatment Centre (CWTC) or other licensed facilities on a
need basis, routing to
be determined by the licensed collectors
|
|
Land-based and River-based Sediment
|
Piling works and
excavation works for the Project.
|
Category L Sediment
|
2,088 m3
|
﹞ Beneficial
reuse on site as far as practicable
﹞ Type
1 每 Open sea disposal at marine disposal site(s) allocated by by MFC.
|
Final
disposal site (typically South Cheung Chau / East of Ninepin) shall be
determined by MFC; and disposal arrangement on a need basis
|
|
Category M Sediment
(passed Tier III - biological screening)
|
433 m3
|
﹞ Beneficial
reuse on site as far as practicable
﹞ Type
1 每 Open sea disposal (dedicated site) at marine disposal site(s) allocated
by MFC.
|
Final
disposal site (typically South Cheung Chau / East of Ninepin) shall be
determined by MFC; and disposal arrangement on a need basis
|
|
Category H Sediment
(does not require the Tier III biological screening))
|
319 m3
|
﹞ Beneficial
reuse on site as far as practicable
﹞ Type
2 每 Confined marine disposal at marine disposal site(s) allocated by MFC.
|
Final
disposal site (typically East Sha Chau) shall be determined by MFC; and disposal
arrangement on a need basis
|
6.5
Evaluation of Residual
Environmental Impacts
6.5.1
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.
6.6
Environmental Monitoring and Audit Requirement
Construction Phase
6.6.1
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.
6.6.2
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.
6.6.3
A WMP should be prepared by the
Contractor and submitted to the Engineer of the Project for approval. The recommended mitigation measures
should form the basis of the WMP.
Operational Phase
6.6.4
With the implementation of good
waste management practices, no adverse environmental impacts are expected to
arise, and therefore waste monitoring and audit programme
during the operation phase of the Project is not required.
6.7.1
Waste
types generated by the construction of this Project are likely to include
C&D materials (from excavation, demolition works, site formation, piling
works, and construction of viaduct and stations), general refuse, chemical
wastes from maintenance and servicing of construction plant and equipment, and
land-based and river-based sediments.
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.
6.7.2
The
total volume of excavated sediment generated from the Project is estimated to
be approximately 2,840 m3. Based on the results of the chemical
and biological screening, approximately 2,088 m3 of sediment is suitable for
Type 1 每 Open Sea Disposal, 433 m3 of sediment is suitable for
Type 1 每 Open Sea Disposal (Dedicated Sites) and 319 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 Section
6.4 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.
6.7.3
The main waste types generated
during the operation of the Project would be chemical waste and general refuse
from maintenance activities, staff, and commercial operators. 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.