9. waste management 9.1 introduction · 2016. 11. 17. · rubble, brick, tile, rock, boulder,...
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Outlying Islands Sewerage Stage 2 –
South Lantau Sewerage Works
9-1 B&V / ERM
9. WASTE MANAGEMENT
9.1 Introduction
This Section identifies the potential wastes arising from the construction and operation of the
proposed Project in South Lantau, and assesses the environmental impacts associated with the
handling and disposal of these wastes. The main issues are:
management of dredged marine sediment;
handling and disposal of contaminated soil/sediments;
handling and disposal of Construction and Demolition (C&D) materials (1)
arising
from the construction works; and
chemical wastes, general refuses, industrial wastes and other solid wastes from the
construction works and operational activities.
9.2 Legislation Requirement & Assessment Criteria
The following discussion on legislative requirements and evaluation criteria applies to both
construction and operation phases of the proposed Project.
The criteria and guidelines for evaluating potential waste management implications are laid
out in Annexes 7 and 15 of the EIAO-TM under the EIAO (Cap. 499). The following
legislation covers, or has some bearing upon the handling, treatment and disposal of the
wastes generated from the construction and operation of the proposed Project:
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) - Public Cleansing and
Prevention of Nuisances Regulation; and
Dumping at Sea Ordinance (Cap. 466).
Details on each of the above are presented below.
9.2.1 Waste Disposal Ordinance (Cap. 354)
The Waste Disposal Ordinance (WDO) prohibits the unauthorised disposal of wastes, with
waste defined as any substance or article, which is abandoned. Construction waste is not
directly defined in the WDO but is considered to fall within the category of ‘trade waste’.
(1) “C&D materials” refers to materials arising from any land excavation or formation, civil/building construction, road works, building renovation or
demolition activities. It includes various types of reusable materials, building debris, rubble, earth, concrete, timber and mixed site clearance materials.
When sorted properly, materials suitable for land reclamation and site formation (known as public fill) will be reused at a public filling area or other
land formation /reclamation projects. The rock and concrete can be crushed and processed to produce rock fill or aggregates for various civil and
building engineering applications. The remaining construction waste (comprising timber, paper, plastics and general refuse) are to be disposed of at
landfills.
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Trade waste is defined as waste from any trade, manufacturer or business or any wasted
building, or civil engineering materials, but does not include animal waste.
Under the WDO, wastes can only be disposed of at a licensed site. The WDO provides for
the issuing of licences for the collection and transport of wastes. Licences are not, however,
currently issued for the collection and transport of construction waste or trade waste.
9.2.2 Waste Disposal (Chemical Waste) (General) Regulation (Cap. 354C)
Chemical waste as defined under the Waste Disposal (Chemical Waste) (General) Regulation
includes any substance being scrap material, or unwanted substances specified under Schedule
1 of the Regulation, if the specified substance or chemical occurs in such a form, quantity or
concentration so as to cause pollution or constitute a danger to health or risk of pollution to
the environment.
A person should not produce, or cause to be produced, chemical wastes without registration
with the EPD. Chemical wastes must either be treated using on-site facility licensed by EPD
or be collected by a licensed collector for off-site treatment at a licensed facility. Under
EPD regulations, the waste producer, collector and disposal facility must sign all relevant
parts of a computerised trip ticket for each consignment of waste. The computerised system
is designed to allow the transfer of wastes to be traced from cradle-to-grave.
EPD has also issued a guideline document, the Code of Practice on the Packaging, Labelling
and Storage of Chemical Wastes (1992), which details how the contractor should comply with
regulations on chemical wastes. According this Code of Practice, the waste producer is
required to prepare and make available written emergency procedures for spillage, leakage or
accidents arising from the storage of chemical wastes in order to reduce the risks of pollution
and danger to human health or life. They must also provide their employees with training on
such procedures.
9.2.3 Waste Disposal (Charges for Disposal of Construction Waste) Regulation (Cap. 354N)
The Waste Disposal (Charges for Disposal of Construction Waste) Regulation defined
construction waste as any substance, matters or things that is generated from construction
work and abandoned, whether or not it has been processed or stockpiled before being
abandoned. It does not include any sludge, screening or matter removed in or generated
from any desludging, desilting or dredging works.
The Construction Waste Disposal Charging Scheme entered into operation on 1 December
2005. From that time, the main contractor who undertakes construction work under a
contract with value of HK$1 million or above is required to open a billing account solely for
the contract for waste disposal. Application shall be made within 21 days after the contract
is awarded.
For construction work under a contract with value less than HK$1 million, such as minor
construction or renovation work, any person such as the owner of the premises where the
construction work takes place or his/her contractor can open a billing account. The account
can also be used for contracts each with value less than HK$1 million. The premises owner
concerned may also engage a contractor with a valid billing account to make arrangement for
disposal of construction waste.
Under the Construction Waste Disposal Charging Scheme, charging for disposal of
construction waste started on 20 January 2006 and therefore will apply to this Project.
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Depending on the percentage of inert materials in the construction waste, inert construction
waste can be disposed of at public fill reception facilities. However mixed construction
waste can be disposed of at construction waste sorting facilities, landfills and outlying islands
transfer facilities which have different disposal costs. The scheme encourages reducing,
reusing and sorting of construction waste such that the waste producer can reduce their
disposal fee. Table 9.1 summarises the government construction waste disposal facilities,
types of waste accepted and disposal cost.
Table 9.1 – Government Facilities for Disposal of C&D Materials
Government Waste Disposal
Facilities
Type of Construction Waste Accepted Charge (HK$/
Tonne) #
Public Fill Reception Facilities Consisting entirely of inert construction waste ++ $27
Sorting Facilities Containing more than 50% by weight of inert
construction waste ++
$100
Landfills @ Containing not more than 50% by weight of inert
construction waste ++
$125
Outlying Islands Transfer
Facilities @
Containing any percentage of inert construction
Waste ++
$125
# Except for the Outlying Islands Transfer Facilities, the minimum charge load is 1 tonne, i.e. if a load of
waste weighs 1 tonne or less, it will be charged as 1 tonne. A load of waste weighing more than 1 tonne
will be charged at 0.1 tonne increment. For Outlying Islands Transfer Facilities, the charge is $12.5 per
0.1 tonne and the minimum charge load is 0.1 tonne.
++ Inert construction waste means rock, rubble, boulder, earth, soil, sand, concrete, asphalt, brick, tile,
masonry or used bentonite.
@ If a load of waste contains construction waste and other waste, that load will be regarded as consisting
entirely of construction waste for the purpose of calculating the applicable charge.
9.2.4 Land (Miscellaneous Provisions) Ordinance (Cap. 28)
The inert portion of C&D materials (also called public fill) may be taken to public fill
reception facilities. Public fill reception facilities 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 to obtain a Dumping
Licence from the CEDD. Individual licences and windscreen stickers are issued for each
vehicle involved.
Under the licence conditions, public fill reception facilities will only accept earth, soil, sand,
rubble, brick, tile, rock, boulder, concrete, asphalt, masonry or used bentonite. In addition,
in accordance with paragraph 12 of the DEVB TC(W) No. 6/2010 (2)
, the Public Fill
Committee will advise on the acceptance criteria (e.g. no mixing of construction waste,
nominal size of the materials less than 250 mm, etc). The material should, 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.
(2) DEVB Technical Circular No. 6/2010 (DEVB TC(W) No. 6/2010): Trip Ticket System for Disposal of Construction & Demolition Materials.
Outlying Islands Sewerage Stage 2 –
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9.2.5 Public Health and Municipal Services Ordinance (Cap. 132) - Public Cleansing and Prevention
of Nuisances Regulation
This Regulation provides a further control on the illegal dumping of wastes on unauthorised
(unlicensed) sites.
9.2.6 Dumping at Sea Ordinance (Cap. 466)
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 articles at sea for the protection of the marine environment. Under the DASO,
a marine dumping permit from the DEP is required for the disposal of regulated substances
within and outside the waters of the Hong Kong SAR. The permit contains terms and
conditions that includes 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.
Management of Dredged/ Excavated Sediments for Marine Disposal
Marine disposal of any dredged/excavated sediment is subject to control under the Dumping
at Sea Ordinance (DASO). Dredged/ excavated sediment destined for marine disposal is
classified based on its contaminant levels with reference to the Chemical Exceedance Levels
(CEL), as stipulated in ETWB TC(W) No. 34/2002 (3)
. This practice note includes a set of
sediment quality criteria, as presented in Table 9.2, which includes heavy metals and
metalloids, organic pollutants and a class of contamination level for highly contaminated
sediment not suitable for marine disposal.
Table 9.2 – Dredged/ Excavated Sediment Quality Criteria for the Classification
under the ETWB TC(W) No. 34/2002
Contaminant Lower Chemical
Exceedance Level
(LCEL)
Upper Chemical Exceedance
Level (UCEL)
Metal (mg kg-1 dry weight)
Cadmium (Cd) 1.5 4
Chromium (Cr) 80 160
Copper (Cu) 65 110
Mercury (Hg) 0.5 1
Nickel (Ni) (a) 40 40
Lead (Pb) 75 110
Silver (Ag) 1 2
Zinc (Zn) 200 270
Metalloid (mg kg-1 dry weight)
Arsenic (As) 12 42
(3) ETWB Technical Circular No. 34/2002 (ETWB TC(W) No. 34/2002): Management of Dredged/Excavated Sediment.
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Contaminant Lower Chemical
Exceedance Level
(LCEL)
Upper Chemical Exceedance
Level (UCEL)
Organic-PAHs (g kg-1 dry weight)
Low Molecular Weight (LMW) PAHs 550 3,160
High Molecular Weight (HMW) PAHs 1,700 9,600
Organic-non-PAHs (g kg-1 dry weight)
Total PCBs 23 180
Organometallics (g TBT l-1 in interstitial water)
Tributyl-tin (a) 0.15 0.15
(a) The contaminant level is considered to have exceeded the UCEL if it is greater than the value shown.
The DEP, as the Authority under the DASO, will classify sediments based on their
contaminant levels with reference to the CEL laid down in Table 9.2. In accordance with
ETWB TC(W) No. 34/2002, the sediment is classified into three categories based on its
contamination levels:
Category L: Sediment with all contaminant levels not exceeding the LCEL. The material
must be dredged, transported and disposed of in a manner which reduces the loss of
contaminants either into solution or by re-suspension.
Category M: Sediment with any one or more contaminants in the sediment exceeding the
LCEL with none exceeding the UCEL. The material must be dredged and transported with
care, and must be effectively isolated from the environment upon final disposal unless
appropriate biological tests demonstrate that the material will not adversely affect the marine
environment.
Category H: Sediment with any one or more contaminants in the sediment exceeding the
UCEL. The material must be dredged and transported with great care, and must be
effectively isolated from the environment upon final disposal.
Figure 9.1 summarises the sediment classification and disposal arrangements. EPD will use
the sediment and biological test results to determine the most appropriate disposal site (e.g.
open sea or confined marine disposal site).
In addition, any proposal to remove more than 500,000 m3 of clean mud or any quantity of
contaminated mud must be justified on both cost and environmental grounds. The rationale
for such removal will also be provided to enable an allocation for disposal to be considered.
Therefore it is desirable to demonstrate that any proposed sediment dredging has been
reduced as far as reasonably and safely practicable and to obtain, in-principle, an agreement
from the Secretary of the Marine Fill Committee (MFC) of the CEDD at an early stage.
9.2.7 Other Relevant Guidelines
Other guideline documents which detail how the Contractor will comply with the WDO and
its associated regulations include:
Waste Disposal Plan for Hong Kong (December 1989), Planning, Environment and
Lands Branch Government Secretariat, Hong Kong Government;
Chapter 9 - Environment (2008), Hong Kong Planning Standards and Guidelines,
Hong Kong Government;
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New Disposal Arrangements for Construction Waste (1992), EPD & CED, Hong
Kong Government;
Code of Practice on the Packaging, Labelling and Storage of Chemical Wastes
(1992), EPD, Hong Kong Government;
Hong Kong Planning Standards and Guidelines Planning (2014), Planning
Department, Hong Kong SAR Government;
WBTC No. 2/93, Public Dumps, Works Branch, Hong Kong Government;
WBTC No. 2/93B, Public Filling Facilities, Works Branch, Hong Kong SAR
Government;
WBTC No. 16/96, Wet Soil in Public Dumps, Works Branch, Hong Kong Government;
WBTC Nos. 4/98 and 4/98A, Use of Public Fill in Reclamation and Earth Filling
Projects, Works Bureau, Hong Kong SAR Government;
Waste Reduction Framework Plan, 1998 to 2007, Planning, Environment and Lands
Bureau, Government Secretariat, 5 November 1998;
WBTC No. 12/2000, Fill Management, Works Bureau, Hong Kong SAR Government;
WBTC No. 19/2001, Metallic Site Hoardings and Signboards, Works Bureau, Hong
Kong SAR Government; WBTC No. 12/2002, Specifications Facilitating the Use of
Recycled Aggregates. Works Bureau, Hong Kong SAR Government;
WBTC No. 11/2002 - Control of Site Crushers, Works Bureau, Hong Kong SAR
Government;
WBTC No. 12/2002 - Specifications Facilitating the Use of Recycled Aggregates,
Works Bureau, Hong Kong SAR Government;
ETWB TC(W) Nos. 22/2003 and 22/2003A, Additional Measures to Improve Site
Cleanliness and Control Mosquito Breeding on Construction Sites;
ETWB TC(W) No. 33/2002 - Management of Construction and Demolition Material
Including Rock, Environment, Transport and Works Bureau, Hong Kong SAR
Government;
ETWB TC(W) No. 34/2002, Management of Dredged/Excavated Sediment,
Environment, Transport and Works Bureau, Hong Kong SAR Government;
ETWB TC(W) No. 19/2005, Environmental Management on Construction Sites,
Environment, Transport and Works Bureau, Hong Kong SAR Government;
DEVB TC(W) No. 6/2010, Trip Ticket System for Disposal of Construction &
Demolition Materials, Development Bureau, Hong Kong SAR Government;
DEVB TC(W) No. 8/2010, Enhanced Specification for Site Cleanliness and Tidiness,
Development Bureau, Hong Kong SAR Government;
Section 3.3 of Chapter 2 of Project Administration Handbook for Civil Engineering
Works, 2012 Edition, Civil Engineering and Development Department, Hong Kong
SAR Government;
Sections 4.1.3 and 4.13 of Chapter 4 of Project Administration Handbook for Civil
Engineering Works, 2012 Edition, Civil Engineering and Development Department,
Hong Kong SAR Government;
Section 9.12 of Chapter 5 of Project Administration Handbook for Civil Engineering
Works, 2012 Edition, Civil Engineering and Development Department, Hong Kong
SAR Government;
Section 21.25 of Chapter 7 of Project Administration Handbook for Civil Engineering
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Works, 2012 Edition, Civil Engineering and Development Department, Hong Kong
SAR Government;
Hong Kong Planning Standards and Guidelines Planning (2014), Planning
Department, Hong Kong SAR Government;
WBTC No. 25/99, 25/99A and 25/99C - Incorporation of Information on Construction
and Demolition Material Management in Public Works Subcommittee Papers, Works
Bureau, Hong Kong SAR Government; and
Practice Note for Authorized Persons and Registered Structural Engineers No. 252 -
Management Framework for Disposal of Dredged/Excavated Sediment, Buildings
Department, Hong Kong SAR Government.
9.3 Expected Waste Sources
9.3.1 Construction Phase
Option evaluation has been conducted to try to avoid waste generation and maximize reuse
and recycling of waste generated from the construction of the proposed Project. During the
planning and design stages, options for layout, construction methods and programme have
been considered and the proposed scheme comprises the proposed best balance. Section 2
contains more discussion on the alternatives that were considered to reduce the volumes of
wastes generated by this Project.
During the construction phase, the main activities that will result in generation of waste
include site clearance, land excavation, backfilling, facilities installation works and marine
dredging. The typical waste types associated with these activities include:
dredged marine sediment from submarine outfall construction;
excavated material from site formation works and pipe laying;
C&D material from construction of new buildings;
chemical wastes; and
general refuse.
9.3.2 Operation Phase
The proposed village sewerage and trunk sewerage works are expected to be automated and
unmanned during the operation phase. Operation of the San Shek Wan STW will be manned
with a few personnel. The typical waste types associated with operational activities include:
dewatered sludge from STW operation;
chemical wastes e.g. from maintenance works; and
solid wastes/by-products generated from routine cleaning and maintenance activities,
e.g. screenings and grits.
9.4 Impact Assessment
The potential environmental impacts associated with the handling and disposal of waste
arising from the construction and operation of the Project were assessed in accordance with
the criteria presented in Annexes 7 and 15 of the EIAO-TM and summarised as follows:
estimation of the types (i.e. quality), timing and quantities of the wastes to be
generated based on information provided by the engineering design team and the
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relevant information on waste generation;
assessment of the secondary environmental impacts due to the management of waste
with respect to potential hazards, air and odour emissions, noise, wastewater
discharges and traffic; and
assessment of the potential impacts on the capacity of waste collection, transfer and
disposal facilities.
9.4.1 Construction Phase
9.4.1.1 Dredged Marine Sediment
(a) Estimation
To minimise dredging in Pui O Bay, the submarine outfall pipe will be constructed by
Horizontal Directional Drilling (HDD) method from the STW. As a result, only minor
dredging of the seabed will be required for the installation of the submarine outfall diffuser.
Approximately 4,700 m3 (in situ volume, 6,110 m
3 for bulk volume) of marine sediment will
be dredged, and the dredging works will be completed within one month approximately.
A marine sediment sampling programme has been undertaken in December 2010 in response
to the recommendation in the Desk Study Report for Site Investigation and Laboratory
Testings (2010) of this Study and the EIA Study Brief to provide an indication of the quality of
the sediment and the volumes of different types of sediment to be dredged. The sediment
sampling and testing proposal and testing results were described in the Final Site
Investigation, Surveys and Testings Report (Volume 2 – Environmental, Part 1) issued on 27
February 2012. (Annex 9A contains the relevant pages of the report). The sediment sampling
programme, including the sampling stations, the chemical analysis suite and the biological
testing programme, was developed based on the guidelines described in ETWB TC(W) No.
34/2002 - Management of Dredged / Excavated Sediment. The contaminants tested include
all the contaminants stated in Table 1 - Analytical Methodology in Appendix B of ETWB
TC(W) No. 34/2002, and all sediment samples were evaluated for sediment quality parameters
as listed in the Appendix A of the ETWB TC(W) No. 34/2002. Two vibrocores were taken
vertically down to the proposed dredging depth (i.e. at seabed, 0.9 m, 1.9 m, 2.9 m, 3.9 m, 4.9
m, 5.9 m and 6.9 m below the seabed and at the end of the vibrocore sampling) or upon
refusal, or when encountering rock head (see Figure 9.2), and a total of 14 sediment samples
from up to eight seabed layers were analysed.
Results of the vibrocore sampling programme indicate that all 14 samples tested have
negligible concentration of toxic organics since they were all below the detection limits of the
chemical analysis (see Table 9.3). Metal and metalloid concentrations in all 14 samples
were below the Lower Chemical Exceedance Level (LCEL). Based on the results of the
chemical testing, sediment from both locations and all depths were classified as Category L
uncontaminated materials. Therefore the dredged sediment generated from this Project will
be disposed of at the South Cheung Chau or East of Ninepin disposal facilities designated for
open sea disposal of uncontaminated sediment.
The testing results presented in this Report are for EIA purposes only. The project
proponent and the contractor of this Project will implement the Project in accordance with the
Dumping at Sea Ordinance (DASO) and the procedures and requirements specified in the
ETWB TC(W) No. 34/2002 prior to the commencement of the dredging activities and a marine
dumping permit will be obtained.
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(b) Potential Environmental Impacts Associated with the Disposal of Dredged Sediment
The dredged sediment will be loaded on to the barge and temporary stored in the barge.
About 8 barge trips within the dredging month will transfer the dredged sediment to the
disposal facilities at South Cheung Chau or East of Ninepin disposal facilities. The bottom
of the barge will be properly sealed to avoid the leakage of sediment during transporting.
With the proper disposal of the small quantity of dredged sediment, no unacceptable
environmental impacts are expected.
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Table 9.3 – Results of Marine Sediment Testing Sample Reference Heavy Metals (mg kg-1) Organics (g kg-1) Organo-
metallics
(g TBT l-1)
Sediment
Category
Disposal
Option
Sample
ID
Depth
(m)
From-To
Silver
(Ag)
Arsenic
(As)
Cadmium
(Cd)
Chromium
(Cr)
Copper
(Cu)
Nickel
(Ni)
Lead
(Pb)
Zinc
(Zn)
Mercury
(Hg)
Total
PCB
LMW
PAHs
HMW
PAHs
Tributyl-tin
(TBT)
Reporting Limits 0.1 1 0.2 1 1 1 1 1 0.05 18 550 1700 0.015
LCEL 1 12 1.5 80 65 40 75 200 0.5 23 550 1700 0.15
UCEL 2 42 4 160 110 40 110 270 1 180 3160 9600 0.15
SD1 0-0.9m < 0.1 5 < 0.2 14 5 8 18 36 < 0.05 <18 <550 <1700 <0.015 L Type 1
0.9-1.9m < 0.1 5 < 0.2 16 6 10 19 40 < 0.05 <18 <550 <1700 -- + L Type 1
1.9-2.9m < 0.1 5 < 0.2 16 4 10 17 37 < 0.05 <18 <550 <1700 -- + L Type 1
2.9-3.9m < 0.1 5 < 0.2 17 4 10 18 39 < 0.05 <18 <550 <1700 -- + L Type 1
3.9-4.9m < 0.1 5 < 0.2 16 4 10 15 36 < 0.05 <18 <550 <1700 -- + L Type 1
4.9-5.9m < 0.1 12 < 0.2 31 10 21 27 62 < 0.05 <18 <550 <1700 -- + L Type 1
5.9-6.9m < 0.1 6 < 0.2 11 4 7 13 20 < 0.05 <18 <550 <1700 -- + L Type 1
6.9-7.4m < 0.1 12 < 0.2 5 2 4 41 26 < 0.05 <18 <550 <1700 -- + L Type 1
SD2 0-0.9m < 0.1 5 < 0.2 13 4 8 16 32 < 0.05 <18 <550 <1700 <0.015 L Type 1
0.9-1.9m < 0.1 5 < 0.2 16 5 9 19 38 < 0.05 <18 <550 <1700 -- + L Type 1
1.9-2.9m < 0.1 4 < 0.2 14 3 8 14 32 < 0.05 <18 <550 <1700 -- + L Type 1
2.9-3.9m < 0.1 6 < 0.2 18 4 11 17 39 < 0.05 <18 <550 <1700 -- + L Type 1
3.9-4.9m < 0.1 4 < 0.2 14 3 8 15 31 < 0.05 <18 <550 <1700 -- + L Type 1
4.9-5.9m < 0.1 10 < 0.2 31 10 22 28 61 < 0.05 <18 <550 <1700 -- + L Type 1
Notes:
(a) Shaded Cell = Exceeding LCEL, classified as Category M, which requires biological screening to determine the types of disposal site (i.e. Type 1 Dedicated or Type 2 Disposal).
(b) Shaded Cell and underlined = Exceeding UCEL, classified as Category H, Type 3 Disposal.
(c) Type 1 Disposal = open sea disposal.
(d) Type 1 (Dedicated) Disposal = disposal at dedicated site.
(e) Type 2 Disposal = disposal at confined marine disposal site.
(f) L: Category L material; M: Category Mpass material; Mfail: Category Mfail material
+ Not tested due to insufficient sample from interstitial water
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9.4.1.2 Excavated Material and Construction Waste
(a) Estimation
A total of approximately 246,000 m3 of excavated material will be generated from the
construction activities, and about 178,300 m3 of suitable inert fill material (e.g. sand and rock)
will be reuse on-site for backfilling the works areas. The reuse of inert excavated material
will be maximised during the backfilling works where practicable, and surplus excavated
material (about 67,700 m3, based on the available engineering and site investigation data to-
date) will be disposed of off-site at public fill reception facilities (e.g. in Mui Wo or other
locations as agreed with CEDD). Advance consent from the Public Fill Committee (PFC)
has been sought and they have no comment on the proposed disposal of the anticipated
amount of surplus excavated material at the public fill reception facilities (Annex 9C).
A breakdown of the quantities of excavated material, fill material and surplus material
associated with this Project is presented in Table 9.4.
Table 9.4 – Summary of Quantity of Excavated Material, Fill Material & Surplus Material
(in situ Volume)
Project Facility Excavated Materials
(m3)
Fill Materials (m3) Surplus Materials
for disposal (m3)
Gravity pipes, manholes, trunk
sewers and twin rising mains
200,000 169,000 31,000
Sewage pumping station (for a total
of six)
16,000 7,300 8,700
Sewage Treatment Works 30,000 2,000 28,000
Total (m3) 246,000 178,300 67,700
The excavated materials to be reused will be properly stored on site for reuse. For
construction of STW and sewage pumping stations, the excavated materials to be reused (i.e.
9,300 m3 out of 178,300 m
3) will be temporarily and properly stored in the adequate areas
within the STW or sewage pumping station sites (i.e. the future accesses, working areas and
landscaping areas of the STW or sewage pumping stations) for backfilling after completion of
the substructures. For construction of sewers and rising mains, the excavated materials to be
reused will be temporarily and properly stored behind the excavated trenches as far as
practicable for backfilling after pipe laying. It should be noted that the sewers and rising
mains will be constructed section by section and hence the excavated materials to be reused
(i.e. 169,000 m3 out of 178,300 m
3) will be generated and reused bit by bit during the whole
construction periods of Packages B and C tentatively from mid-2018 to early 2024. A
substantial alternative storage area is therefore not needed.
Review of the previous and existing land uses of the Project area since 1980s (Annex 9B)
indicated that the Project area consists mainly of natural landscape and private residential land
use. As such the proposed excavated areas are not expected to be located on potentially
contaminated land and thus potential concern for contaminated soil excavation is not
anticipated.
Small quantities of construction waste, such as cleared vegetation, timber, paper and plastics,
are also expected to be generated during construction. They will be reused and recycled as
far as practicable and the small quantities that cannot be reused/ recycled will be disposed of
at landfills via the Outlying Islands Transfer Facilities (OITF) in Mui Wo (‘Mui Wo Transfer
Facility’).
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(b) Potential Environmental Impacts Associated with the Disposal of Excavated Material and
Construction Waste
Based on the preliminary works programme described in Section 3.6 and the quantity of
surplus material presented in Table 9.4, the quantity of excavated material for disposal each
month was calculated and presented in Table 9.5.
Table 9.5 –Quantity of Surplus Excavated Material for Off-site Disposal (in-situ volume) Works Package Surplus Excavated
Material for
disposal (m3)
Construction Period Surplus Excavated Material
for disposal per month (m3)
Package A 28,000 Aug 2017 – Jan 2023 (66 months) (a) 824 (b)
Package B 19,850 (c) Aug 2018 – Aug 2023 (61 months) 331 (e)
Package C 19,850 (d) Feb 2019 – Feb 2024 (61 months) 325 (e)
Notes:
(a) Tentative construction period for civil works, assuming excavation material to be produced during the civil works period only.
(b) Assuming surplus material will be from the excavation work period anticipated during the first 34 months of construction (Aug 2017 – May 2020).
(c) Assuming 15,500 m3 from the construction of village sewers and associated rising mains and 4,350 m3 from the construction of three sewage pumping stations.
(d) Assuming 15,500 m3 from the construction of village sewers and associated rising mains and 4,350 m3 from the construction of three sewage pumping stations.
(e) Assuming excavation work will be evenly spread over the entire construction period as the work will be done section by section along the proposed sewerage network.
The peak disposal period will be from Oct 2018 to Apr 2022 where a maximum of 1,491 m3
of excavated material will require disposal each month. It is estimated that only a maximum
of 12 truck trips per days will be required to dispose the surplus materials off-site (4)
.
In view of the small quantity of excavated material and construction waste generated and with
proper implementation of good site practices and mitigation measures recommended in
Section 9.5, potential dust, noise and water quality impacts associated with on-site handling
and transportation of the surplus excavated material and construction waste to the disposal
sites are not expected.
9.4.1.3 C&D Material from New Building Construction
(a) Estimation
C&D material will be generated during the construction of the new buildings (i.e. the sewage
pumping stations and the STW). In accordance with the Reduction of Construction Waste
Final Report (5)
, the C&D materials generation rate of 0.1 m3 per 1 m
2 of GFA is adopted for
assessing the C&D material generation from the construction of the sewage pumping stations
and the STW. The GFA of each of the sewage pumping stations and the STW is estimated
to be about 293 m2 and 8,040 m
2, respectively. It is thus expected that the construction of
each sewage pumping station and the STW will generate 29.3 m3 (a total of 176 m
3 for six
pumping stations) and 804 m3 of C&D materials respectively. With proper segregation, the
volume of the inert C&D material that could be reused as public fill is approximately 784 m3
(4) Assuming a capacity of 7 m3 per truck, bulk factor of 1.4 and 25 working days per month.
(5) Hong Kong Polytechnics (March 1993) Reduction of Construction Waste Final Report.
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and the volume of construction waste is approximately 196 m3. The exact amount of C&D
material to be generated would be quantified in the site Waste Management Plan to be
prepared by the Contractor. The public fill portion of the C&D materials (784 m3) will be
disposed of at the Mui Wo Temporary Public Fill Reception Facility while the construction
waste (196 m3) will be disposed of at landfills via the Mui Wo Transfer Facility.
(b) Potential Environmental Impacts Associated with the Disposal of C&D Material
Based on the preliminary works programme described in Section 3.6 and the quantity of C&D
material estimated, the quantity of C&D material for disposal each month was calculated and
presented in Table 9.6.
Table 9.6 –Quantity of C&D Material for Off-site Disposal Works Package C&D Material for
disposal (m3)
Construction Period C&D Material for disposal
per month (m3) (a)
Package A Public Fill: 643.2 Aug 2017 – Jan 2023 (66 months) Public Fill 10.72
Construction Waste: 160.8 Construction Waste: 2.68
Package B Public Fill: 70.4 Aug 2018 – Aug 2023 (61 months) Public Fill: 1.17
Construction Waste: 17.6 Construction Waste: 0.29
Package C Public Fill: 70.4 Feb 2019 – Feb 2024 (61 months) Public Fill: 1.17
Construction Waste: 17.6 Construction Waste: 0.29
Notes:
(a) Assuming C&D material to be generated throughout the construction period.
The peak disposal period will be from Oct 2018 to Apr 2022 where a maximum of 13.1 m3 of
public fill and 3.3 m3 of construction waste will require disposal each month. It is estimated
that only a maximum of 3 truck trips per month will be required to dispose the C&D material
off-site. In view of the small quantity of C&D materials generated and with proper
implementation of good site practices and mitigation measures recommended in Section 9.5,
potential dust, noise and water quality impacts associated with on-site handling and
transportation of the C&D material to the disposal sites are not expected.
9.4.1.4 Chemical Wastes
Chemical waste, as defined under the Waste Disposal (Chemical Waste) (General) Regulation,
includes any substance being scrap material, or unwanted substances specified under Schedule
1 of the Regulation. A complete list of such substances is provided under the Regulation.
However, substances likely to be generated from the construction of this Project will, for the
most part, arise from the equipment associated with the construction works. These may
include, but not limited to the following:
scrap batteries or spent acid/alkali from their maintenance;
used engine oils, hydraulic fluids and waste fuel;
spent mineral oils/cleaning fluids from mechanical machinery; and
spent solvents/solutions from equipment cleaning activities.
Chemical wastes may pose environmental, health and safety hazards if not stored and
disposed of in an appropriate manner as outlined in the Waste Disposal (Chemical Waste)
(General) Regulation and the Code of Practice on the Packaging, Labelling and Storage of
Chemical Wastes. These hazards may include:
toxic effects to workers;
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adverse effects on air, water and land from spills; and
fire hazards.
The amount of chemical wastes that will arise from the construction activities will be highly
dependent on the contractor’s on-site maintenance activities and the quantity of plant and
equipment utilized. With respect to the nature of construction works and the types of
equipment to be used on site, it is estimated that about a few hundred litres of used lubricant
oil will be generated per month during the construction period. It is anticipated that the
quantities of waste solvent and wasted oils will be minimal.
With the incorporation of suitable arrangements for the storage, handling, transportation and
disposal of chemical wastes under the requirements stated in the Code of Practice on the
Packaging, Labelling and Storage of Chemical Waste, no adverse environmental and health
impacts, and hazards will result from the handling, transportation and disposal of chemical
waste arising from the Project.
9.4.1.5 General Refuse
The presence of a construction site with workers and associated site facilities will result in the
generation of general refuse (mainly consist of food waste, aluminium cans and waste paper)
which requires off-site disposal. The storage of general refuse has the potential to give rise
to adverse environmental impacts. These include odour if the waste is not collected
frequently (for example, daily), windblown litter, water quality impacts if waste enters water
bodies, and visual impact.
It is conservatively estimated that up to 100 construction workers will be working on site at
any one time, with a general refuse generation rate of 0.65 kg per worker per day (6)
, the
amount of general refuse to be generated will only be about 65 kg per day.
Recyclable materials such as paper and aluminium cans will be separated and delivered to the
recyclers. The non-recyclable waste will be collected and disposed of at the Mui Wo
Transfer Facility for disposal at landfills. With respect to the small quantity of additional
general refuse to be transferred to landfills, it is not anticipated that it will cause unacceptable
operational impact to these facilities.
Provided that the mitigation measures recommended in Section 9.5 are adopted, no
unacceptable environmental impacts caused by the storage, handling, transport and disposal of
general refuse are expected.
9.4.2 Operation Phase
9.4.2.1 Dewatered Sludge from STW
Based on the present design capacity of the STW, approximately 3 m3 (about 0.75 tonnes) of
dewatered sludge (30% of dry solids) will be generated from the treatment process per day.
Dewatered sludge will be stored properly in covered containers within the STW to avoid
odour nuisance, prior to removal for disposal at landfills or the proposed Sludge Treatment
Facility in Tuen Mun by truck or via Mui Wo Transfer Facility (7)
. As the Project will be
(6) This is considered as a conservative estimate based on the number reported in a number of EIA reports approved under the EIAO.
(7) Mui Wo Transfer Facility is allowed to accept 35 tonnes of Type 2 dewatered sludge (with at least 30% of dry solids) each day and is currently receiving
about 2 tonnes of sludge per day. Hence, it should have sufficient capacity to receive the dewatered sludge from the Project. This method of
transporting waste in bulk is expected to reduce the overall transportation cost and greatly reduce the traffic and environmental nuisance associated
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commissioned in 2022/23, it is expected that the dewatered sludge will be disposed of at
Sludge Treatment Facility.
With proper implementation of the mitigation measures described in Section 9.5, no
unacceptable environmental impacts caused by the storage, handling, transport and disposal of
the small quantity of dewatered sludge are expected.
9.4.2.2 Chemical Waste
A small amount of chemical waste will be generated from maintenance works during project
operation. However, the amount of chemical waste that will arise from the maintenance
works will be highly dependent on site practices. It is estimated that about a hundred litres
of used chemical wastes will be generated each month during the project operation.
9.4.2.3 Other Solid Wastes/ By-products
The village sewerage, trunk sewerage and the STW will undergo regular cleaning and
maintenance activities during operation. Screening and grit removal will generate solid
wastes such as debris at a rate of about 1 m3 per day from each sewage pumping station and 1
m3 per day from the STW (i.e. a total of about 2,600 m
3 per year). Screenings are expected
to be compacted first. Compacted screenings and grits will be stored in closed containers.
Facilities will be provided within the sewage pumping stations and STW for temporary
storage of screenings and grits in sealed drums or skips prior to removal for disposal by trucks.
Screenings and grits are expected to be disposed of at the Mui Wo Transfer Facility for
disposal at landfills.
With proper implementation of the mitigation measures described in Section 9.5, no
unacceptable environmental impacts caused by the storage, handling, transport and disposal of
screenings and grits are expected.
9.5 Mitigation Measures
9.5.1 Waste Management Hierarchy
The various waste management options are categorised in terms of preference from an
environmental viewpoint. The options considered to be most preferable have the least
environmental impacts and are more sustainable in the long term. The hierarchy is as
follows:
avoidance and reduction;
reuse of materials;
recovery and recycling; and
treatment and disposal.
The above hierarchy has been used to evaluate and select waste management options. The
aim has been to reduce waste generation and reduce waste handling and disposal costs.
The future contractor shall be requested to prepare and submit a Waste Management Plan
(WMP) in accordance with the requirements set out in the ETWB TC(W) No. 19/2005 –
Environmental Management on Construction Sites, for the approval of the Engineer's
with more truck trips on the road. DSD will liaise with the relevant division in EPD to seek advance agreement for the disposal arrangement of
dewatered sludge via Mui Wo Transfer Facility.
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Representative. The WMP shall include monthly and yearly Waste Flow Tables that will
indicate the amounts of waste generated, recycled and disposed of (including final disposal
site). The Contractor’s waste management practices and effectiveness shall be audited by the
Engineer's Representative on regular basis. The project proponent will confirm that the
contractor has consulted EPD for the final disposal of wastes and as appropriate implement
the standard site practices and mitigation measures recommended in this Study as listed below:
nomination of approved personnel to be responsible for standard site practices,
arrangements for collection and effective disposal to an appropriate facility of all
wastes generated at the site;
training of site personnel in proper waste management and chemical handling
procedures. Training will be provided to workers on the concepts of site cleanliness
and appropriate waste management procedures, including waste reduction, reuse and
recycling at the beginning of the construction works;
provision of sufficient waste disposal points and regular collection for disposal;
appropriate measures to reduce windblown litter and dust during transportation of
waste by either covering trucks or by transporting wastes in enclosed containers;
separation of chemical wastes for special handling and appropriate treatment at the
Chemical Waste Treatment Centre at Tsing Yi;
regular cleaning and maintenance programme for drainage systems, sumps and oil
interceptors; and
a recording system for the amount of wastes generated, recycled and disposed
(including disposal sites) will be proposed and implemented.
9.5.2 Waste Reduction Measures
Good management and control can prevent generation of significant amount of waste.
Waste reduction is best achieved at the planning and design stage, as well as by ensuring the
implementation of standard site practices. Recommendations to achieve waste reduction
include:
segregation and storage of different types of waste in different containers, skips or
stockpiles to enhance reuse or recycling of material and their proper disposal;
encourage collection of aluminium cans and waste paper by individual collectors
during construction with separate labelled bins provided to segregate these wastes
from other general refuse by the workforce;
any unused chemicals and those with remaining functional capacity will be recycled as
far as possible;
use of reusable non-timber formwork to reduce the amount of C&D materials;
prior to disposal of construction waste, wood, steel and other metals will be separated
to the extent practical, for re-use and/or recycling to reduce the quantity of waste to be
disposed of to landfill;
proper storage and site practices to reduce the potential for damage or contamination
of construction materials; and
plan and stock construction materials carefully to reduce amount of waste generated
and avoid unnecessary generation of waste.
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9.5.3 Construction Phase
9.5.3.1 Dredged Marine Sediment
The requirements and procedures detailed in the ETWB TC(W) No. 34/2002 and under the
DASO will be followed. A proposal for sampling and chemical testing of the sediment will
be prepared and submitted to the EPD for approval. The approved detailed sampling and
chemical testing will be carried out prior to the commencement of the dredging activities to
confirm the sediment disposal method. After carrying out the sampling and testing, a
Sediment Quality Report (SQR) will be prepared for EPD approval as required under the
DASO. The SQR will include the sampling details, chemical testing results, quality control
records, proposed classification and delineation of sediment according to the requirements of
the Appendix A of ETWB TC(W) No. 34/2002.
9.5.3.2 Excavated Material and C&D Material
(a) Management of Waste Disposal
The contractor will open a billing account with EPD in accordance with the Waste Disposal
(Charges for Disposal of Construction Waste) Regulation for the payment of disposal charges.
Every waste load transferred to Government waste disposal facilities such as public fill,
sorting facilities, landfills or transfer facility will require a valid “Chit” which contains the
information of the account holder to facilitate waste transaction recording and billing to the
waste producer.
A trip-ticket system will be established in accordance with DEVB TC(W) No. 6/2010 to
monitor the reuse of surplus excavated materials off-site and disposal of construction waste
and general refuse at transfer facilities/ landfills, and to control fly-tipping. The billing “chit”
and trip ticket system will be included as one of the contractual requirements and
implemented by the contractor. The project proponent will also conduct regular inspection
of the waste management measures implemented on site as described in the Waste
Management Plan, which becomes part of the Environmental Management Plan according to
the requirements as stipulated in ETWB TC(W) No. 19/2005, to be prepared before
commencement of construction.
A recording system (similar to summary table as shown in Annex 4 of Appendix C of ETWB
TC(W) No. 19/2005) for the amount of waste generated, recycled and disposed of (including
the disposal sites) will be established during the construction phase.
(b) Measures for the Reduction of C&D Material Generation
Inert C&D materials (public fill) will be reused within the Project as far as practicable.
Public fill and construction waste shall be segregated and stored in different containers or
skips to facilitate reuse or recycling of materials and their proper disposal. Specific areas of
the work site will be designated for such segregation and storage if immediate use is not
practicable.
To reduce the potential dust and water quality impacts of site formation works, C&D
materials will be wetted as quickly as possible to the extent practice after filling. Open
stockpiles of excavated/ fill materials or construction wastes on-site should be covered with
tarpaulin or similar fabric.
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9.5.3.3 Chemical Waste
Chemical waste producers will be registered with the EPD.
Chemical waste, as defined by Schedule 1 of the Waste Disposal (Chemical Waste) (General)
Regulation, will be handled in accordance with the Code of Practice on the Packaging,
Handling and Storage of Chemical Wastes as follows. Containers used for storage of
chemical wastes will:
be suitable for the substance they are holding, resistant to corrosion, maintained in a
good condition, and securely closed;
have a capacity of less than 450 L unless the specifications have been approved by the
EPD; and
display a label in English and Chinese in accordance with instructions prescribed in
Schedule 2 of the Regulation.
The storage area for chemical wastes will:
be clearly labelled and used solely for the storage of chemical waste;
be enclosed on at least 3 sides;
have an impermeable floor and bund, of capacity to accommodate 110% of the volume
of the largest container or 20% by volume of the chemical waste stored in that area,
whichever is the greatest;
have adequate ventilation;
be sufficiently covered to prevent rainfall entering (water collected within the bund
must be tested and disposed of as chemical waste, if necessary); and
be arranged so that incompatible materials are appropriately separated.
Chemical waste will be disposed of:
via a licensed waste collector; and
to a facility licensed to receive chemical waste, such as the Chemical Waste Treatment
Facility in Tsing Yi which also offers a chemical waste collection service and can
supply the necessary storage containers.
9.5.3.4 General Refuse
General refuse will be stored in enclosed bins or compaction units separately from
construction and chemical wastes. Adequate number of waste containers will be provided to
avoid over-spillage of waste on site. A reputable waste collector will be employed by the
Contractor to remove general refuse from the site, separately from construction and chemical
wastes, on a daily basis to minimise odour, pest and litter impacts. The burning of refuse on
construction sites is prohibited by law.
Recycling bins will be provided at strategic locations to facilitate recovery of aluminium can
and waste paper from the site. Materials recovered will be sold for recycling.
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9.5.4 Operation Phase
9.5.4.1 Dewatered Sludge from STW
The practices of good housekeeping for STW shall be followed as far as practicable to reduce
potential odour impact from handling, collection, transportation and disposal of dewatered
sludge, including:
sludge will be stored properly in covered containers within the STW;
sludge containers should be flushed with water regularly; and
frequent sludge removal from storage containers is necessary to prevent the production
of gases.
9.5.4.2 Chemical Waste
Chemical wastes will be handled, stored, collected, transferred and disposed of as per the
guidelines, requirements and controls applicable for the management of chemical wastes, as
described in Section 9.5.3.3.
9.5.4.3 Other Solid Wastes/ By-products
The following standard practice will be followed as far as practicable to reduce potential
environmental impacts associated with solid wastes generated from cleaning/ maintenance
activities:
screens should be cleaned regularly to remove any accumulated organic debris;
grit and screening transfer systems should be flushed regularly with water to remove
organic debris and grit; and
screenings and grits shall be transferred and stored in closed containers.
9.6 Residual Impacts
9.6.1 Construction Phase
With the implementation of the recommended measures, no unacceptable residual impacts are
anticipated.
9.6.2 Operation Phase
With the implementation of the recommended measures, no unacceptable residual impacts are
anticipated.
9.7 Environmental Monitoring & Audit
9.7.1 Construction Phase
Waste management would be the contractor’s responsibility to ensure that all wastes produced
during the construction of the Project are handled, stored, collected, transferred and disposed
of in accordance with good waste management practices and EPD’s regulations and
requirements.
To facilitate monitoring and control over the contractor’s performance on waste management,
a waste inspection and audit programme will be implemented throughout the construction
phase. The programme will look at the aspects of waste management including waste
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generation, storage, recycling, transport and disposal. The aims of the waste inspection and
audit programme are:
to review the contractor’s Waste Management Plan (WMP), which becomes part of
the Environmental Management Plan according to the requirements as stipulated in
ETWB TC(W) No. 19/2005, including the quantities and types of C&D materials
generated, reused and disposed of off-site, the amount of fill materials exported
from/imported to the site and the quantity of timber used in temporary works
construction for each process/activity;
to confirm that the wastes arising from works are handled, stored, collected,
transferred and disposed of in an environmentally acceptable manner and comply with
the relevant requirements under the Waste Disposal Ordinance (WDO) and its
regulations;
to confirm that the construction contractor properly implements the appropriate
environmental protection and waste pollution control mitigation measures, as outlined
in the WMP and this EIA report, to reduce and control the potential for waste impacts.
to monitor the implementation and achievement of the WMP on site to assess its
effectiveness; and
to monitor the follow-up action on deficiencies identified.
Site inspections and audits will be undertaken during project construction. The inspection/
audit will look at all aspects of on-site waste management practices including waste
generation, storage, recycling, transport and disposal. Apart from site inspection, documents
including licences, permits, disposal and recycling records will be reviewed and audited for
compliance with the legislation and contract requirements. Any irregularities observed
during the site audits will be raised promptly to the contractor for rectification.
9.7.2 Operation Phase
As no unacceptable environmental impacts are expected to arise with the implementation of
standard waste management practices, waste monitoring and audit programme is not required
for the operation phase of the Project.
9.8 Conclusions
This Section of the EIA has described the potential sources of wastes associated with the
construction and operation of the proposed Project in South Lantau. The purpose of the
assessment is to evaluate the acceptability of environmental impacts arising from waste
handling, storage, collection, transfer and disposal.
Table 9.7 summarises the type, quantity and disposal/transfer location of waste to be
generated from the construction of this Project.
Table 9.7 – Summary of Waste to be Generated by this Project
Type of Waste Quantity Proposed Disposal Location
Construction Phase
Marine sediment 4,700 m3 (a) Type 1 Disposal at South Cheung Chau or East of
Ninepin
Surplus excavated material 67,700 m3 (a) Mui Wo Temporary Public Fill Reception Facility or
other location as agreed with CEDD
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Type of Waste Quantity Proposed Disposal Location
C&D material - inert 784 m3 Mui Wo Temporary Public Fill Reception Facility
C&D material – non-inert 196 m3 Mui Wo Transfer Facility
Chemical Waste (used lubricant oil) Few hundred
litres per
month
Chemical Waste Treatment Centre in Tsing Yi
General Refuse 65 kg per day Mui Wo Transfer Facility
Operation Phase
Dewatered Sludge 3 m3 per day Landfill or Sludge Treatment Facility by truck or via Mui
Wo Transfer Facility
Chemical waste from maintenance
work
About a
hundred litre
per month
Chemical Waste Treatment Centre at Tsing Yi
Waste from regular cleaning and
maintenance
2,600 m3 per
year
Mui Wo Transfer Facility
Notes:
(a) In-situ volume
Quantities of dredged marine sediment, excavated material, C&D material, chemical wastes
and general refuse generated from Project construction are estimated based on best
engineering estimates at the time of reporting. Due to the relatively small quantities of
wastes and with the implementation of standard site practices and mitigation measures, no
unacceptable impacts are anticipated during project construction.
Quantities of dewatered sludge, chemical wastes and screenings/grits generated from Project
operation are estimated based on current engineering design. With proper implementation of
the recommended mitigation measures, no unacceptable impacts are anticipated to arise from
project operation.
Relevant guidelines and criteria stipulated under the Waste Disposal Ordinance (Cap. 354),
Land (Miscellaneous Provisions) Ordinance (Cap. 28), Public Health and Municipal Services
Ordinance (Cap. 132), Dumping at Sea Ordinance (Cap. 466) and relevant government
technical circulars and regulations on waste management will be observed and implemented
where applicable.
A Waste Management Plan, which becomes part of the Environmental Management Plan
according to the requirements as stipulated in ETWB TC(W) No. 19/2005, will be prepared
by the contractor and will be audited through a waste inspection and audit programme to
reduce the potential environmental impacts arising from waste management during Project
construction. No specific waste monitoring and audit programme is recommended for
Project operation.