This
Section identifies the potential waste
management implications arising from the construction and operation of the
Project and the potential environmental impacts associated with the storage,
handling, transportation and disposal of the wastes.
The criteria for evaluating waste management
implications are stated in Annex 7 of
the EIAO-TM. Annex
15 of the EIAO-TM prescribes the
general approach and methodology for assessing the waste management
implications caused by a project or proposal.
The
following legislation covers the handling, treatment and disposal of wastes in
Hong Kong which are relevant to the types of waste to be generated from the
Project, and has been considered in the assessment.
·
Waste Disposal Ordinance (WDO) (Cap 354);
·
Waste Disposal (Chemical Waste) (General)
Regulation (Cap 354C);
·
Buildings Ordinance (Cap 123);
·
Land (Miscellaneous Provisions) Ordinance
(Cap 28);
·
Public Health and Municipal Services Ordinance (Cap 132) - Public Cleansing and
Prevention of Nuisances Regulation;
·
Dumping
at Sea Ordinance (DASO) (Cap. 466); and
·
Merchant
Shipping (Prevention and Control of Pollution) Ordinance (Cap 413).
The
WDO prohibits the unauthorised
disposal of wastes, with waste defined as any substance or article which is
abandoned. Under the WDO, wastes can only be disposed of at
licensed waste disposal sites. A
breach of these regulations can lead to the imposition of a fine and/or a
prison sentence. The WDO also provides for the issuing of
licences for the collection and transport of wastes. Licences for the collection and
transport of construction waste or trade waste, however, are not issued
currently.
The
Waste Disposal (Charges for Disposal of
Construction Waste) Regulation defined construction waste as any substance,
matters or things that are generated from construction work and abandoned,
whether or not it has been processed or stockpiled before being abandoned, but
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 came into operation on 1 December 2005. Processing of account applications by
the EPD started on the same day. A
Contractor who undertakes construction work with value of HK$1 million or above
is required to open a billing account solely for the contract. Charging for the disposal of
construction waste started on 20 January 2006.
Depending
on the percentage of inert materials in the material, construction waste can be
disposed of at public fill reception facilities, construction waste sorting
facilities, landfills and outlying islands transfer facilities, where differing
disposal costs would be applied.
This scheme encourages waste reduction and hence minimise the costs of
the Contractor or the Project Proponent.
Table
8.1 summarises the Government waste disposal
facilities for construction waste and various charge levels.
Table 8.1 Government
Waste Disposal Facilities for Construction Waste
|
Government Waste Disposal
Facilities |
Type of Construction Waste
Accepted |
Charge per Tonne (a) |
|
Public fill
reception facilities |
Consisting
entirely of inert construction waste (b) |
HK$71 |
|
Sorting facilities |
Containing more
than 50% by weight of inert construction waste (b) |
HK$175 |
|
Landfills (c) |
Containing not
more than 50% by weight of inert construction waste (b) |
HK$200 |
|
Outlying Islands
Transfer Facilities (c) |
Containing any
percentage of inert construction waste (b) |
HK$200 |
|
Notes: (a) 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 $20 per 0.1 tonne and the minimum charge load is
0.1 tonne. (b) Inert construction waste means rock,
rubble, boulder, earth, soil, sand, concrete, asphalt, brick, tile, masonry
or used bentonite. (c) If a load of waste contains construction
waste and other wastes, that load will be regarded as consisting entirely of
construction waste for the purpose of calculating the applicable charge. |
||
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 such a 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.
Chemical
waste producers shall register with the EPD. Any person who contravenes this
requirement commits an offence and is liable to a fine and imprisonment. Producers of chemical wastes must treat
their wastes, utilising on-site plants licensed by the EPD or have a licensed
collector take the wastes to a licensed facility. For each consignment of wastes, the
waste producer, collector and disposer of the wastes must sign all relevant
parts of a computerised trip ticket.
The system is designed to allow the transfer of wastes to be traced from
cradle-to-grave.
The
Regulation prescribes the storage
facilities to be provided on site including labelling and warning signs. To minimise the risks of pollution and
danger to human health or life, the waste producer is required to prepare and
make available written procedures to be observed in the case of emergencies due
to spillage, leakage or accidents arising from the storage of chemical wastes. He/she must also provide employees with
training in such procedures.
Regulation
of private projects, as opposed to government public works projects, is subject
to the Buildings Ordinance (BO) and
relevant Practice Notes for Authorised
Persons, Registered Structural Engineers and Registered Geotechnical Engineers
(PNAPs). Measures have been
introduced under PNAP ADV-19 Construction
and Demolition Waste, to enhance the management of construction and
demolition (C&D) materials, and to minimise its generation
at source. The enhancement measures
include:
·
Identifying opportunities to prevent waste
during both the project planning and design stage as well as construction
stage; and
·
Requiring the Contractor to prepare a Waste
Management Plan (WMP) including areas described in PNAP ADV-19 and submit to the Project Proponent for agreement.
The
inert portion of construction waste ([1]) (also called public fill) may be taken to public fill
reception facilities. Public fill
reception facilities are operated by the Civil Engineering and Development
Department (CEDD). The Land (Miscellaneous Provisions) Ordinance requires
that individuals or companies who deliver public fill to the public fill
reception facilities need to obtain Dumping Licences. The licences are issued by the CEDD
under delegated authority from the Director of Lands.
Under
the licence conditions, public fill reception facilities will only accept inert
earth, soil, sand, rock, boulder, rubble, brick, tile, concrete, asphalt,
masonry or used bentonite. In
addition, in accordance with paragraph 11 of Development Bureau (DevB) Technical Circular (Works) (DevB TC(W)) No.
6/2010), the Public Fill Committee will advise on the acceptance criteria
(e.g. no mixing of construction waste, nominal size of the materials less than
250mm, 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 to the public fill reception facility.
This
Regulation provides further control
on the illegal dumping of wastes on unauthorised (unlicensed) sites. The illegal dumping of wastes can lead
to a fine and/or imprisonment.
Under
the DASO, a permit from the Director
of Environmental Protection is required if anyone intends to dispose and dump
from vessels in the sea. The permit
is valid for specific periods of time and stipulates the (1) type and quantity
of substances to be dumped; (2) location of the disposal grounds; (3)
requirement of equipment for monitoring the disposal operations; and (4)
environmental monitoring requirements.
PNAP ADV-21 – Management Framework for
Disposal of Dredged/ Excavated Sediment (April
2007), sets out the procedures for seeking approval to dredge/ excavate
sediment and the management framework for marine disposal of such
sediment. This PNAP outlines the requirements to be followed in assessing and
classifying the sediment and explains the marine disposal arrangement for the
classified material.
Table
8.2 summarises the HKSAR Government charging
system for proponents of private projects to dispose of dredged sediment.
Table 8.2 HKSAR
Government Charging System for Disposal of Dredged Sediment
|
Sediment Type |
Charge Rate per Cubic Metre
(measured in situ at dredging site) |
|
Type 1 -
Open Sea Disposal of Category L Sediment |
HK$1.67 |
|
Others |
HK$87.00 |
The Merchant Shipping
(Prevention and Control of Pollution) Ordinance and its subsidiary
regulations prohibit the discharge of wastewater and garbage from vessels.
Hong Kong has implemented the International Convention
for the Prevention of Pollution from Ships 1973 as amended by the 1978 Protocol
(universally known as MARPOL) and the MARPOL related requirements are mainly
implemented under the Merchant Shipping
(Prevention and Control of Pollution) Ordinance. Under the requirements, liquid oil waste
or any other mixtures which contain oil and noxious liquid substances or any
such residues shall not be discharged into the sea. In Hong Kong, the Chemical Waste
Treatment Centre (CWTC) is the reception facility for oily waste discharged
from vessels.
Other
relevant guidance documents, which detail how the Project Proponent or the
Contractor should comply with the local regulations, are as follows:
·
Waste
Disposal Plan for Hong Kong (December 1989), Planning, Environment and
Lands Branch Government Secretariat, HKSAR Government;
·
Code
of Practice on the Packaging, Labelling and Storage of Chemical Wastes
(1992), EPD, HKSAR Government;
·
Hong
Kong Planning Standards and Guidelines Planning
(2014), Planning Department, HKSAR
Government;
·
WBTC
No. 2/93 - Public Dumps, Works Branch, HKSAR Government;
·
WBTC
No. 2/93B - Public Filling Facilities,
Works Branch, HKSAR Government;
·
WBTC
No. 16/96 - Wet Soil in Public Dumps,
Works Branch, HKSAR Government;
·
Waste
Reduction Framework Plan, 1998 to 2007,
Planning, Environment and Lands Bureau, Government Secretariat, 5 November
1998;
·
WBTC
No. 4/98 and 4/98A - Use of Public Fill in Reclamation and Earth Filling
Projects, Works Bureau, HKSAR Government;
·
WBTC
No. 12/2000 - Fill Management, Works Bureau, HKSAR
Government;
·
WBTC
No. 19/2001 - Metallic Site Hoardings and Signboards;
Works Bureau, HKSAR Government;
·
Project
Administration Handbook for Civil Engineering Works, Section 21.25 of Chapter 7
and Section 9.12 of Chapter 5 - Control of Site Crushers,
HKSAR Government;
·
WBTC No. 12/2002 - Specifications
Facilitating the Use of Recycled Aggregates, Works Bureau, HKSAR Government;
·
Project
Administration Handbook for Civil Engineering Works, Section 4.1.3 of Chapter 4
- Management of Construction and Demolition Material Including Rock, HKSAR Government;
·
ETWB
TC(W) No. 19/2005 - Environmental
Management on Construction Sites, Environment, Transport and Works Bureau,
HKSAR Government; and
·
DevB
TC(W) No. 6/2010 - Trip Ticket System for Disposal of Construction &
Demolition Materials, Development Bureau, HKSAR Government.
During the construction phase of the Project, the main
activities include marine piling works, concreting, assembly of pre-fabricated equipment,
electrical and mechanical installations, subsea pipeline construction,
including marine dredging and jetting, and onshore pipework fabrication. These activities will potentially result
in the generation of wastes.
The typical waste types associated with these
activities include:
·
Dredged marine
sediment from the construction of the BPPS Pipeline and the LPS Pipeline;
·
C&D materials
from the construction of the GRSs at the BPPS and the LPS and the Jetty, and
onshore pipeline trenching and pipework fabrication;
·
Chemical waste from
maintenance of construction plant and equipment for both land and marine-based
works; and
·
General refuse from
land and marine-based construction workforce and floating refuse.
Options
will be further developed and evaluated to reduce waste generation and enhance
re-use and recycling of waste generated during the detailed design and
construction phases of the Project.
The consideration of options for layout, construction methods and
programme, and the proposed scheme will comprise the proposed best
balance.
For the construction of the BPPS Pipeline and the LPS
Pipeline, dredging will be limited to those areas where non-dredged is not
appropriate. Justification for the
proposed pipeline construction methods has been provided in Section 2 of this EIA
Report and elaborated below. It is
noted that the construction of the Jetty has avoided marine dredging.
For
the BPPS and LPS Pipelines, a number of subsea pipeline construction methods
have been considered. Options are
examined based on a number of environmental parameters where minimizing the
dredged sediment volumes is one of the key factors (alongside WQOs compliance
and minimizing ecological impacts) for the overall environmental acceptability
of the Project. Ploughing,
Horizontal Directional Drilling (HDD) and jetting are non-dredged options which
do not generate dredged sediments. However,
ploughing and HDD are not considered as viable pipeline construction methods for
the Project for several reasons.
Ploughing is
not suitable for the soft marine clay that is found on the seabed along the
routes of the pipelines and cannot provide sufficient burial depth for pipeline
protection. In addition, a
full-scale trial and detailed site survey will be required to establish its
engineering and environmental viability prior to its adoption in Hong Kong,
lengthening the duration of environmental impacts from the Project. HDD’s technical challenges, including
the need to maintain an open drill hole in the soft marine clay on the seabed along the routes of the
pipelines and the use of long pipelines with large pipeline diameters, make its
feasibility questionable. The HDD
operations will also have significant environmental impact e.g. waste
management and water quality impacts from the spoil generation which
may be lengthy in nature given the potential programme and costs
constraints. In addition, HDD
operations may require a number of intermediate offshore working stations which
in turn increase the environmental impact and marine operational risks.
Hence,
a combination of dredging (either grab dredging or Trailing Suction Hopper
Dredger (TSHD) dredging) or jetting is the preferred construction methods for
the BPPS Pipeline and the LPS Pipeline where the selection of the actual
methods to be adopted for pipeline construction are assessed based on the
features along each pipeline route that will impact on the construction methods
and the pipeline protection that is required at certain locations along the
pipeline routes. While dredging
produces marine sediment that may require disposal, jetting on the other hand
may, in comparison to dredging, impact water quality to a higher degree owing
to the temporary increase in suspended sediment concentrations in the
vicinity. It is important to strike
a balance in the selection of appropriate construction methods for the subsea
pipelines. The use of jetting is
preferred to minimise the dredged sediment volumes and therefore the majority
of the BPPS Pipeline and the LPS Pipeline routes are planned to be constructed
by jetting except the pipeline segments (the Urmston Road, West of Lung Kwu
Chau and Southwest Lantau BPPS Pipeline segments) which have to be constructed
by dredging (grab dredging or TSHD dredging) to provide the required level of
pipeline protection from large anchor drop and drag. From an engineering point of view,
protection from anchor drop and drag can be achieved using a combination of
burial depth and rock armour which position the pipe below the normal dragging
depth of the anchors. However,
along pipeline section that requires a higher level of protection, options for
protection of a jetted pipeline include: (a) deep burial below existing seabed
level where the larger anchors cannot reach, which is not feasible with
existing jetting technology; or (b) provision of a fit-for-purpose rock armour
berm, which may protrude above the seabed and is compromised by the fluidized
state of the mud. On the basis of
these, jetting is considered to be not feasible for such pipeline
sections. Figure 8.1
shows the proposed extent of dredging required for the Project. The total estimated in situ volume of
dredged marine sediment is approximately 0.35Mm3. It is expected that the dredging works
will last for about six months.
Marine sediment sampling and testing has already been
undertaken by other developments (for example, approved EIAs, EM&A programmes,
and EPD monitoring stations) near the proposed dredging areas and the marine
sediment quality information relevant to the Project was reviewed.
Details of the previous sampling and testing results are contained
in the Marine Sediment Sampling and Testing
Plan (MSSTP) prepared for this EIA Study in Annex 8A. The previous testing results suggested
that the marine sediment in the vicinity of the BPPS Pipeline route and the LPS
Pipeline route was generally categorised as category L to M, and category L
respectively ([2]),
whereas the marine sediment in the vicinity of the Jetty was generally
categorized as category L.
A
sediment sampling programme was agreed with EPD and undertaken as part of this
EIA Study to delineate the locations of the contaminated marine sediment
potentially to be dredged by this Project and enable subsequent estimation of
the different types of marine sediments (i.e. contaminated and uncontaminated)
to be disposed of for the purpose of the EIA Study. A MSSTP was prepared and submitted to
the EPD for approval prior to the commencement of the field sampling works (see
Annex 8A). Marine sediment samples have been collected
per plan. At each location,
sediment samples were collected at the top layer of the seabed by grab sampling
in view of the trench design. The
marine sediment samples were then tested in accordance with the requirements
stipulated in the PNAP ADV-21 issued
by the Buildings Department.
The marine sediment analytical results for the 15 nos.
of locations along the BPPS Pipeline and the LPS Pipeline
where it was identified during the design development and optimisation that
dredging may be required, as shown in Figure 8.2, are presented in Table 8.3 ([3]). The full laboratory analytical results
of the relevant sampling locations are contained in Annex 8B. The testing results are compared against the Lower Chemical Exceedance
Level (LCEL) and Upper Chemical Exceedance Level (UCEL) of respective
parameters in Table 8.3.
Table 8.3 Marine
Sediment Testing Results
|
Sample Reference |
Chemical Screening |
Sediment Category |
Biological Screening |
Disposal Option |
|||||||||||||
|
Heavy Metals (mg kg-1) |
Organic (ug kg-1) |
Organo-metallics |
|||||||||||||||
|
Sampling Location |
Sampling Method |
Ag(a) |
As(a) |
Cd(a) |
Cr(a) |
Cu(a) |
Ni(a) |
Pb(a) |
Zn(a) |
Hg(a) |
Total PCB |
LMW PAHs |
HMW PAHs |
Tributyl-tin (ug TBT L-1) |
|||
|
Reporting Limits |
|
0.1 |
1 |
0.2 |
8 |
7 |
4 |
8 |
20 |
0.05 |
3 |
55 |
170 |
0.015 |
|||
|
LCEL |
|
1 |
12 |
1.5 |
80 |
65 |
40 |
75 |
200 |
0.5 |
23 |
550 |
1,700 |
0.15 |
|||
|
UCEL |
|
2 |
42 |
4 |
160 |
110 |
40 |
110 |
270 |
1 |
180 |
3,160 |
9,600 |
0.15 |
|||
|
X-GB01 |
Grab |
0.2 |
12 |
<0.2 |
34 |
32 |
20 |
33 |
107 |
0.11 |
<18 |
<550 |
<1,700 |
<0.015 |
L |
- |
Type 1 Open
Sea |
|
B-GB01 |
Grab |
0.1 |
13 |
<0.2 |
29 |
14 |
14 |
30 |
75 |
0.05 |
<18 |
<550 |
<1,700 |
<0.015 |
M |
Pass |
Type 1 Dedicated
Sites |
|
B-GB02 |
Grab |
0.1 |
15 |
<0.2 |
32 |
15 |
12 |
30 |
67 |
0.05 |
<18 |
<550 |
<1,700 |
<0.015 |
M |
Pass |
Type 1
Dedicated Sites |
|
B-GB03 |
Grab |
0.1 |
15 |
<0.2 |
35 |
20 |
18 |
30 |
77 |
0.07 |
<18 |
<550 |
<1,700 |
<0.015 |
M |
Pass |
Type 1
Dedicated Sites |
|
B-GB04 |
Grab |
0.1 |
16 |
<0.2 |
36 |
24 |
21 |
28 |
87 |
0.07 |
<18 |
<550 |
<1,700 |
<0.015 |
M |
Pass |
Type 1
Dedicated Sites |
|
B-GB05 |
Grab |
0.2 |
18 |
<0.2 |
53 |
35 |
28 |
40 |
117 |
0.10 |
<18 |
<550 |
<1,700 |
<0.015 |
M |
Pass |
Type 1
Dedicated Sites |
|
B-GB10 |
Grab |
0.1 |
20 |
<0.2 |
47 |
28 |
24 |
33 |
101 |
0.09 |
<18 |
<550 |
<1,700 |
<0.015 |
M |
Pass |
Type 1
Dedicated Sites |
|
B-GB11 |
Grab |
0.1 |
16 |
<0.2 |
44 |
24 |
22 |
30 |
90 |
0.08 |
<18 |
<550 |
<1,700 |
<0.015 |
M |
Pass |
Type 1
Dedicated Sites |
|
B-GB12 |
Grab |
0.1 |
13 |
<0.2 |
35 |
20 |
20 |
33 |
86 |
0.09 |
<18 |
<550 |
<1,700 |
<0.015 |
M |
Pass |
Type 1
Dedicated Sites |
|
B-GB13 |
Grab |
0.1 |
14 |
<0.2 |
35 |
21 |
20 |
29 |
79 |
0.08 |
<18 |
<550 |
<1,700 |
<0.015 |
M |
Pass |
Type 1
Dedicated Sites |
|
B-GB14 |
Grab |
<0.1 |
21 |
<0.2 |
30 |
16 |
19 |
40 |
73 |
0.06 |
<18 |
<550 |
<1,700 |
<0.015 |
M |
Pass |
Type 1
Dedicated Sites |
|
B-GB15 |
Grab |
<0.1 |
12 |
<0.2 |
32 |
17 |
17 |
27 |
74 |
0.09 |
<18 |
<550 |
<1,700 |
<0.015 |
L |
- |
Type 1 Open
Sea |
|
F-GB01 |
Grab |
0.1 |
8 |
<0.2 |
31 |
16 |
16 |
33 |
76 |
0.07 |
<18 |
<550 |
<1,700 |
<0.015 |
L |
- |
Type 1 Open
Sea |
|
F-GB02 |
Grab |
0.1 |
9 |
<0.2 |
32 |
16 |
18 |
31 |
78 |
0.08 |
<18 |
<550 |
<1,700 |
<0.015 |
L |
- |
Type 1 Open
Sea |
|
L-GB01 |
Grab |
0.2 |
8 |
<0.2 |
41 |
23 |
27 |
37 |
107 |
0.1 |
<18 |
<550 |
<1,700 |
<0.015 |
L |
- |
Type 1 Open
Sea |
|
Note: (a)
Heavy metals tested includes: silver
(Ag), arsenic (As), cadmium (Cd), chromium (Cr), copper (Cu), nickel (Ni),
lead (Pb), zinc (Zn) and mercury (Hg). (b) Bold = Exceeding LCEL, classified as Category M (c) Bold and underlined = Exceeding UCEL,
classified as Category H |
|
||||||||||||||||
As shown in Table 8.3 and Figure 8.2,
the marine sediments to be dredged (i) near the Jetty, (ii) southwest of Lantau,
(iii) near the LPS and (iv) near the BPPS were found to be uncontaminated, and
would be disposed to Type 1 open sea disposal sites (i.e. South of Cheung Chau
or East of Ninepin). The estimated
in situ volumes of uncontaminated sediment to be dredged under this Project are
0.01Mm3 for the BPPS Pipeline and 0.02Mm3 for the LPS
Pipeline. The
allocation of disposal space will be subject to further review and approval by
the Marine Fill Committee (MFC) of CEDD.
No category M marine sediments were found to be
present along the LPS Pipeline in the proposed dredging areas. Marine sediment to be dredged along the
BPPS Pipeline from southwest of Lantau to the BPPS were found to be category M
contaminated. Tier
III biological screening was conducted to identify the most appropriate
disposal option for the category M contaminated materials in accordance with
the PNAP ADV-21. Results of the biological screening
indicated that all sediment samples passed all three toxicity tests. It is thus estimated that approximately
0.32Mm3 (in situ volume) of category
M contaminated sediment which passed the biological screening test (Cat M pass
sediment) would be generated from the BPPS Pipeline.
These findings of the marine sediment testing are
consistent with the information from the review of the previous marine sediment
quality information along the BPPS and LPS Pipelines in Annex 8A.
The
detailed breakdown of the estimated quantities of different types of marine
sediments is summarised in Table 8.4.
Table 8.4 Estimated
Quantities (in situ) of Different Types of Marine Sediment to be Dredged (Mm3)
(a)
|
Sediment Type |
BPPS
Pipeline |
LPS
Pipeline |
Total |
Disposal Option |
|
Category L |
0.01 |
0.02 |
0.03 |
Type 1 Open Sea Disposal Site managed by the CEDD |
|
Category M pass |
0.32 |
- |
0.32 |
Type 1 Dedicated Open Sea Disposal Site |
|
Total |
0.33 |
0.02 |
0.35 |
|
Note:
(a) The estimated quantities
of sediments are estimated based on the preliminary trench design but did not
take into consideration the detailed dredged profile or the vertical
distribution of contamination and the quantities presented in the table above
are considered primary and conservative.
A detailed sampling, testing and estimation of contaminated sediment
will be carried out under the Dumping at Sea Ordinance (DASO) Cap .466 and a
DASO permit would be obtained prior to the commencement of the marine
construction works.
The options of on-site or off-site treatment and reuse
of the dredged sediment have been explored. The
Project does not require natural backfilling material and thus the potential of
on-site re-use of dredged marine sediment is very limited. Off-site re-use of the dredged marine
sediment after decontamination and treatment of contaminated marine sediment
into earth filling material has been considered. The cement-stabilisation process converts soft marine
mud into a green recycled earth filling material which is safe to the
environment and can be compacted by normal compaction machinery to achieve the
necessary engineering properties similar to the parent ground, such that after
backfilled it can provide similar resistance to foundations of the proposed
development. The specific
performance criteria for quality control at both the cement-stabilisation stage
and the backfilling/compaction state consist of particular major technical
requirements in terms of shear strength, dry density, etc. Pilot trials on mixing and field
operations on site and quality control tests to demonstrate the suitability of
the cement-stabilisation and backfilling/compaction processes would be
required. Some on-site re-use of
such treated material may be considered for the Jetty substructure seabed area,
subject to detailed design and construction plan. Nevertheless, a
considerably large stockpile area will be required for the storage and drying
of dredged marine sediments of high water content before they can be mixed with
cement and granular materials to form backfilling materials. Therefore, in order to make the option of off-site
treatment both cost effective and environmentally friendly, it would be
necessary to secure a plot of land with barging facilities (e.g. under a short-term
tenancy agreement) and within reasonable transportation distance from where the
dredged sediments will be generated.
The feasibility of off-site treatment and beneficial reuse, including
the quantity of dredged sediment that could be handled, will be confirmed
during the detailed design and implementation phase of the Project.
Surplus dredged marine sediment that cannot be reused
will require off-site disposal. Various
disposal options of category M sediment have been considered, including both
land-based and marine-based disposal options with reference to the recommended
sediment disposal options for submarine utilities installation in the final
report of CEDD’s Study on Options for Management of Contaminated Sediment in
Hong Kong ([4]). On land-based options, the applicability
to reuse marine sediment as construction fill or sanitary landfill cover
depends on the type, size and quality of the dredged material and requires
dewatering, screening and remediation treatment prior to reuse (see earlier
text on the consideration of treatment options). In fact, for fill material for
construction projects and landfill cover, reuse of inert excavated materials
rather than reuse of dredged sediment after treatment is still preferred
because it does not require treatment and hence more environmentally friendly
and cost effective. Hence, the
demand for dredged marine sediment on land application is uncertain which
affects the viability of land-based disposal options. Given the above, marine disposal option
is considered more appropriate for surplus dredged sediment that cannot be
reused.
At present the East
of Sha Chau Mud Pits are designated for confined marine sediment disposal of
contaminated sediment. The current
capacity of these pits is around 4.6Mm3 for contaminated sediment
and these pits could be considered as the disposal site for the category M
contaminated marine sediments generated from this Project. In
accordance with PNAP ADV-21, the project proponent will liaise with MFC
and EPD at an early stage of the project, as to the allocation arrangement for
sediment disposal. The Project Proponent will continue to
liaise with the relevant authorities to ensure compliance with PNAP ADV-21.
The testing results and the disposal options
presented in this EIA Report are for
EIA purposes only. To confirm the
marine sediment disposal quantity and location, a separate MSSTP and Sediment Quality Report (SQR) will be prepared in accordance
with the requirement stated in PNAP
ADV-21 for EPD approval as required under the Dumping at Sea Ordinance. The actual quantity and allocation of
the disposal site(s) will be based on the results of the SQR to be approved by
MFC/ CEDD and a dumping permit will be obtained from EPD prior to the commencement
of the dredging works.
The dredged marine
sediments will be loaded on to the barge immediately. With the assumption of typical barge
capacity of 800m3 to 1,000m3, approximately 7 to 8 barge
trips per day are anticipated to transfer the marine sediments to the disposal
sites during the pipeline construction period. The barges to be used will be fitted
with seals to prevent leakage of marine sediment, and no overloading of marine
sediment and marine sediment laden water will be allowed during loading or
transportation. As such no adverse
impact on water quality and marine ecology associated with the barge transport
of marine sediments and their disposal is expected.
C&D materials (consisting of waste concrete,
packing materials, plastics, etc.) will mainly be generated from the
construction of the GRSs at the BPPS and the LPS and the Jetty. Since GRS construction will only involve
minor fencing and trenching works and assembly of prefabricated equipment and
the Jetty construction will involve some structural formation works, mainly
consisting of the assembly of prefabricated equipment, the quantity of C&D
materials generation is expected to be small. The estimated total quantity of C&D
materials to be generated under this Project is around 45,000m3, or
around 2,100m3 per month on average during the construction period,
of which about 90% would be inert (e.g. concrete, bricks and rocks, etc.) and
the rest being non-inert. The
construction sequence will be carefully planned so as to avoid over-ordering of
construction material. The minor
trenching works for GRS construction and onshore pipeline trenching and
pipework would not require significant land excavation works, thus the
potential concern about contaminated soil excavation is not expected.
Specific areas will be designated for C&D material
segregation onsite (including land and marine-based
construction sites and marine vessels used for the construction of marine
works) into inert materials (public fill) and
non-inert materials. Recyclables,
such as plastics and cardboard, will be segregated for recycling. The public fill from the construction of
the GRS and onshore pipeline at the BPPS, if any, will be transported by truck
to the Tuen Mun Area 38 Fill Bank via Lung Kwu Tan Road while the non-inert
C&D materials will be disposed of at WENT Landfill via Nim Wan Road. Public fill and non-inert C&D
materials generated from the GRS and onshore pipeline at the LPS, if any, and
the Jetty will be transported by barge/marine vessel to the public fill
reception facilities (e.g. Tuen Mun Area 38 or Mui Wo Temporary Public Fill
Reception Facility which receive public fill only) or the Outlying Island
Transfer Facilities (which receive both public fill and non-inert C&D
material). Given that the quantity
of C&D materials for disposal is anticipated to be low, the handling and
transportation of C&D materials are not expected to cause adverse dust,
noise or water quality impacts with the implementation of good construction
site practices.
About 0.84Mm3 and 0.26Mm3 of
rock is required to be imported as pipeline protection material (rock armour)
for the BPPS Pipeline and the LPS Pipeline, respectively. Based on the construction programme,
approximately 10 and 4 barge trips per day are required to deliver the rock to
the floating storage barge along the BPPS Pipeline and the LPS Pipeline,
respectively, during the pipeline construction period. Water quality impacts associated with
rock armour placement is addressed in Section 7.7.1. To optimise the import and use of rock,
where possible, liaison with
concurrent rock-generating projects (e.g. Tseung Kwan O - Lam Tin Tunnel,
Relocation of Sha Tin Sewage Treatment Works to Caverns and Central Kowloon
Route projects) would be made to explore the feasibility of local matching.
Chemical
waste, as defined under the Waste
Disposal (Chemical Waste) (General) Regulation, includes any unwanted
substances specified under Schedule 1 of
the Regulation. Substances likely to be generated from
the construction of GRSs at the BPPS and the LPS, the BPPS Pipeline and LPS
Pipeline and the Jetty will include:
·
Used paint,
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;
·
Adverse
effects on air, water and land from spills; and
·
Fire
hazards.
It
is difficult to quantify the exact amount of chemical waste that will arise
from the construction activities since it will be highly dependent on the
Contractor’s on-site maintenance activities and the quantity and/or types of
plant and equipment utilised. With
respect to the scale of the construction activities, it is anticipated that the
quantity of chemical waste to be generated is about a few hundred litres of
used lubricant oil per month during the construction period. It is anticipated that the quantities of
waste solvent and wasted paint will be minimal. The chemical waste will be collected by
a licensed chemical waste collector and delivered to the licensed chemical
waste treatment facilities for disposal (at the Chemical Waste Treatment Centre
(CWTC) at Tsing Yi).
With
the incorporation of suitable arrangements for the storage, handling,
collection, transportation and disposal of chemical wastes under the
requirements stated in the Waste Disposal
(Chemical Waste) (General) Regulation and the Code of Practice on the Packaging, Labelling and Storage of Chemical Wastes,
no adverse environmental (including air and odour emissions, noise and
wastewater discharge) impacts, and hazards are anticipated.
The
presence of a construction site at the GRSs at the BPPS and the LPS with
workers and associated site office will result in the generation of general
refuse (mainly consists of food waste, aluminium cans, plastic bottles, waste
paper and glass bottles) which requires off-site disposal. The presence of a construction site in
the open sea at the Jetty site, may also cause trapping of floating refuse ([5])
at the temporary structures and along barges or vessels stationed for the
marine construction works. Such
refuse will require regular collection and off-site disposal as general refuse. The storage of general refuse has the
potential to give rise to adverse environmental impacts, if not properly
managed. These include odour if the
general refuse is not collected frequently, floating/windblown litter and
visual impact.
It
is conservatively estimated that a maximum of about 500-600 construction
workers will be working on the various Project construction sites at any one
time. With a general refuse generation rate of 0.65kg per worker per day, the
maximum amount of general refuse to be generated by the construction workforce
will be about 390kg per day. The
amount of floating refuse, i.e. not generated by this Project as workers are
not allowed to dump rubbish into the sea, is highly variable and influenced by
the strength and direction of water currents. As the Jetty is to be constructed in
open seas with constant flushing of water currents, the amount of floating
refuse, if any, to be trapped at the Site during construction is expected to be
minimal.
To
reduce the quantity of general refuse to be disposed of at landfill, recyclable
materials (i.e. paper, plastic bottles, aluminium cans and glass bottles) will
be segregated on-site (including land and marine-based construction sites and
marine vessels used for the construction of marine works) for off-site recycling,
as far as practicable. Adequate
number of enclosed waste containers and recycling bins will be provided to
avoid over-spillage of waste and/ or recyclable materials.
The
non-recyclable general refuse on marine vessels will be collected for disposal
on shore. The non-recyclable refuse
will be placed in bags/bins at both land and marine-based work sites and
disposed of at WENT Landfill by truck via Nim Wan Road (for the GRS at the
BPPS) or via the Outlying Island Transfer Facilities by barge/marine vessel
(for the GRS at the LPS, LPS and BPPS Pipeline construction and Jetty) on a
regular basis. Given that the
quantity of general refuse to be disposed of at landfill is small, no adverse
impact on the operation of the landfill is anticipated.
With
the implementation of the mitigation measures recommended in Section
8.5, no adverse environmental impacts (including potential hazard, dust
and odour emissions, noise and wastewater discharge) caused by storage,
handling, transport and disposal of general refuse are expected.
During the operation phase of the Project, the major
waste types potentially to be generated include:
·
Industrial waste
from maintenance activities at the GRSs at the BPPS and the LPS and LNG
Terminal;
·
Chemical waste from
maintenance of plant and equipment and the GRSs at the BPPS and the LPS and LNG
Terminal;
·
Dredged marine
sediment from maintenance dredging in the vicinity of the Jetty, if needed; and
·
General refuse from
site operations at the GRSs at the BPPS and the LPS, the LNG Terminal and
floating refuse collected at the LNG Terminal.
Options
will be further developed and evaluated to reduce waste generation and enhance
re-use and recycling of waste generated during the operation phase of the
Project.
Industrial
waste will arise from the maintenance activities at the GRSs and the LNG
Terminal. The wastes may include
minimal quantity of filters and scrap materials from maintenance of plant and
equipment and cleaning materials.
Scrap materials will be collected regularly for recycling, where
appropriate, as such it is not expected that storage, handling, transport and
disposal of industrial waste will cause any adverse environmental impacts. General industrial waste, such as
plastic, metal cans and waste paper, will be collected together with the
general refuse for segregation.
Industrial wastes arising from the LNG Terminal will be temporarily
stored on board the FSRU Vessel and disposed of by barge/marine vessel to the
Outlying Island Transfer Facilities.
Industrial wastes arising from the GRSs at the BPPS and the LPS will be
disposed of, together with the general waste arising from the operation of the
BPPS and the LPS, by truck to the WENT Landfill via Nim Wan Road or Outlying
Island Transfer Facilities by barge/marine vessel respectively.
It
is anticipated that a small amount of chemical waste, including MARPOL waste,
will be generated from maintenance activities at the GRSs at the BPPS and the LPS
and the LNG Terminal. The chemical
wastes may include empty chemical containers, oily rags etc and the quantity to
be generated is expected to be insignificant. The chemical waste will be collected by
a licensed chemical waste collector and delivered to the licensed chemical
waste treatment facilities for disposal at the CWTC at Tsing Yi. With the incorporation of suitable
arrangements for the storage, handling, collection and transportation and
disposal of chemical waste under the requirements stated in the Waste Disposal (Chemical Waste) (General)
Regulation and the Code of Practice
on the Packaging, Labelling and Storage of Chemical Wastes, no adverse
environmental (including air and odour emissions, noise and waste water
discharge) impacts and hazards are anticipated.
It
is anticipated that siltation may deposit of marine sediment at the Site of the
LNG Terminal throughout the Project’s operation. In order to enable the safe navigation
of the visiting LNGC and the FSRU Vessel, to and from the LNG Terminal site,
maintenance dredging may be required once every 5 years (subjected to site
conditions). Maintenance dredging
will be restricted to specific small areas around the LNG Terminal. Bathymetric surveys will be carried out
to ascertain the requirement for any maintenance dredging and the volume of
marine sediment to be removed due to siltation.
Marine
sediment quality testing results in the vicinity of the LNG Terminal
(summarized in Table 8.3), indicate that the marine sediment resulting from
maintenance dredging is anticipated to be uncontaminated and could be disposed
at open sea disposal sites.
Separate marine sediment quality testing would be conducted prior to the
maintenance dredging works to confirm the level of contamination and to
identify the disposal method. The
marine sediment quality testing would follow the requirement set out in the PNAP ADV-21. The final disposal site would be
determined by the MFC and a dumping licence will be obtained from EPD prior to
the commencement of the maintenance dredging works.
The barges to be
used for any marine sediment transport and disposal will be fitted with seals
to prevent leakage of sediment, and no overloading of material and sediment
laden water will be allowed during loading or transportation. As such no adverse impact on water
quality and marine ecology associated with this marine transport and disposal
is expected.
General
refuse will arise from the operation staff and administrative activities at the
LNG Terminal and the GRSs at the BPPS and the LPS. General refuse may consist of food
waste, plastic, aluminium can and waste paper. Assuming that a 50 person crew is
required to operate the LNG Terminal (including FSRU Vessel), with a general
refuse generation rate of 0.65kg per worker per day ([6]), the amount of
general refuse to be generated will be about 32.5kg per day. The operation staff at the GRSs at the
BPPS and the LPS is expected to be existing staff at the BPPS and the LPS who
will carry out infrequent maintenance works. Additional general refuse from the
operation of the GRSs is thus limited.
Floating
refuse may be trapped by the FSRU Vessel, a visiting LNGC and the structure of
the Jetty. However, the likelihood
of entrapment of floating refuse at the LNG Terminal is low as (i) the LNG
Terminal is located in open sea with constant of water currents, (ii) the Jetty
will be constructed on a pile-type or jacket type structure which allows water
flow under it, (iii) the body of the FSRU Vessel and a visiting LNGC are smooth
in nature, which is not prone to trapping and accumulates of floating refuse,
and (iv) a visiting LNGC will only be at berth for a short period. Hence, the quantity of floating refuse
is expected to be low. Floating
refuse, if any, will be collected on an ‘as needed’ basis and disposed of as
general refuse.
To
reduce the quantity of general refuse to be disposed at landfill, recyclable
materials (i.e. paper, plastic bottles, aluminium cans and glass bottles) will
be segregated on-site and delivered to recyclers. The non-recyclable general refuse from
the LNG Terminal will be collected, stored and disposed of by barge/marine
vessel to the Outlying Island Transfer Facilities on a regular basis. General refuse arising from the GRS at
the BPPS and the GRS at the LPS will be disposed of, together with the general
waste arising from the operation of the BPPS and the LPS, by truck to the WENT
Landfill via Nim Wan Road or the Outlying Island Transfer Facilities by barges/
marine vessel, respectively. Given
that the quantity of general refuse to be disposed of at landfill is small, no
adverse environmental impacts (including potential hazard, dust and odour
emissions, noise and wastewater discharge) associated with the handling and
disposal of the general refuse is anticipated.
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;
·
Re-use 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
Contractors will consult the relevant authorities for the final disposal of
wastes and, as appropriate, implement the good site practices and mitigation
measures recommended in this EIA Report and those given below.
·
Nomination of approved personnel to be
responsible for good 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;
·
Provision of sufficient waste disposal
points and regular collection for disposal;
·
Appropriate measures to reduce windblown/
floating 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; and
·
A recording system for the amount of wastes
generated, recycled and disposed of and the disposal sites.
Good
management and control can prevent the 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 good site practices.
Recommendations to achieve waste reduction include:
·
Segregation and storage of different types
of waste in different containers, skips or stockpiles to enhance re-use or
recycling of waste materials 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, be recycled as far as possible;
·
Use of reusable non-timber formwork to
reduce the amount of C&D materials;
·
Prior to disposal of C&D materials,
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 in a
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.
The
assessment indicates that with the implementation of the waste management
practices at the land and marine-based work sites, no adverse environmental
impacts are envisaged for the handling, collection and disposal of waste
arising during the construction phase of the Project.
This
Section
further describes the good construction site practices to avoid or further
reduce the potential environmental impacts associated with the handling,
collection and disposal of marine sediment, C&D materials, chemical waste
and general refuse (including floating refuse) arising from the construction
works.
The
Contractor(s) must ensure that all the necessary waste disposal and marine
dumping permits or licences are obtained prior to the commencement of the
construction works.
The
Contractor(s) will open a billing account with the EPD in accordance with the Waste Disposal (Charges for Disposal of
Construction Waste) Regulation.
Every construction waste or public fill load to be transferred to Government
waste disposal facilities (e.g. public fill reception facilities, sorting
facilities and landfills) will be provided with 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 also be established in accordance with DevB TC(W) No. 6/2010 to monitor the
disposal of construction waste at landfill and to control fly-tipping. The trip-ticket system will be included
as one of the contractual requirements and implemented by the Contractor(s).
A
waste management plan (WMP) as stated in the PNAP ADV-19 for the amount of waste generated, recycled and
disposed of (including the disposal sites) will be established and implemented
during the construction phase as part of the Environmental Management Plan
(EMP). The Contractor will be
required to prepare the EMP and submit it to the Engineer with the Project
Proponent under the Contract for approval prior to implementation.
The
management of dredged marine sediment requirement PNAP ADV-21 will be incorporated in the Contract for the
construction of the Project.
Disposal vessels will be fitted with tight bottom
seals in order to prevent leakage of material during transport.
Barges will be filled to a level, which ensures
that of marine sediment and marine sediment laden water does not spill over
during loading or transport to the disposal site and that adequate freeboard is
maintained to ensure that the decks are not washed by wave action.
After dredging, any excess materials will be
cleaned from decks and exposed fittings before the vessel is moved from the
dredging area.
When the dredged material has been unloaded at the
disposal areas, any material that has accumulated on the deck or other exposed
parts of the vessel will be removed and placed in the hold or a hopper. Under no circumstances will decks be
washed clean in a way that permits material to be released overboard.
Dredgers will maintain adequate clearance between
vessels and the seabed at all states of the tide and reduce operations speed to
ensure that excessive turbidity is not generated by turbulence from vessel
movement or propeller wash.
C&D
materials will be segregated on-site into public fill and non-inert C&D
materials and stored in different containers or skips to facilitate re-use of
the public fill and proper disposal of the non-inert C&D materials. Specific areas of the land and
marine-based construction sites will be designated for such segregation and
storage, if immediate re-use is not practicable. Prefabrication will be adopted as far as
practicable to reduce the C&D materials arising.
The
Contractor(s) will register as a chemical waste producer with the EPD. Chemical waste will be handled in
accordance with the Code of Practice on
the Packaging, Handling and Storage of Chemical Wastes as listed
below.
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 450L 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 Regulations.
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 bunding, 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 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 CWTC which also offers a chemical waste collection service,
and can supply the necessary chemical waste storage containers.
General
refuse (including the floating refuse collected) will be stored in enclosed
bins separately from C&D materials and chemical wastes. Floating refuse will be collected on an
‘as needed’ basis for disposal as general refuse. Workers will be prohibited from throwing
rubbish into the sea and adequate bins will be provided on both land and
marine-based sites and marine vessels.
General refuse will be delivered separately from C&D materials and
chemical wastes for offsite disposal on a regular basis to reduce odour, pest
and litter impacts. General refuse
from the marine vessels will be collected and disposed on shore.
Recycling
bins will be provided at strategic locations within the land and marine-based
construction site and marine vessels to facilitate recovery of recyclable
materials (including aluminium can, waste paper, glass bottles and plastic
bottles) from the Project Site.
Materials recovered will be sold for recycling.
In
addition, to avoid any odour and litter impact, an appropriate number of
portable toilets will be provided for workers on the land and marine-based
sites.
At
the commencement of the construction works, training will be provided to
workers on the concepts of site cleanliness and appropriate waste management
procedures, including waste reduction, re-use and recycling. In particular, the training will
emphasize no dumping of waste into the sea is allowed, particularly at
marine-based work sites and on marine vessels.
Industrial
waste arising from maintenance activities will be segregated. Scrap metals and recyclables will be
sent for recycling to reduce the overall quantity of waste disposed from these
activities.
The
measures for management of chemical waste during operation phase are similar to
those outlined in Section 8.5.2.
The
management of dredged marine sediment shall follow the requirements stipulated
in PNAP ADV-21.
The
measures for management of marine sediment during operation phase are similar
to those outlined in Section 8.5.2.
The
management of general refuse from the GRSs at the BPPS and the LPS and LNG
Terminal staff during the operation phase will be similar to that in the
construction phase (see Section 8.5.2). Floating refuse at the LNG Terminal will
be collected on an ‘as needed’ basis for disposal as general refuse. General refuse and non-recyclables will
be stored in enclosed bins and disposed offsite on a regular basis for
avoidance of pest and odour nuisance.
Recycling bins for recyclable materials (including aluminium can, waste
paper, glass bottles and plastic bottles) will be placed at the site office and
transported off-site for recycling on a regular basis.
Similar
to the training requirement described in Section 8.5.2, prior to the
commencement of the operation phase, training will be provided to all staff
working at the GRSs at the BPPS and the LPS and LNG Terminal on the concepts of
site cleanliness and appropriate waste management procedures, including waste
reduction, re-use and recycling. In
particular, the training will emphasize no dumping of waste into the sea is
allowed, at the LNG Terminal.
No
adverse residual waste management impact is anticipated during the construction
and operation phases of the Project.
During
construction, site audits at both land and marine-based work sites will be
undertaken by the Project Proponent and the Contractor on a monthly basis to
determine if wastes are being managed in accordance with the recommended good
site practices in this EIA Report and the requirements in the WMP. The audits will investigate all aspects
of waste management, including waste generation, storage, handling, recycling,
transportation and disposal, to prevent any dumping of waste into the sea or
malpractice of waste disposal.
As the operation of the GRSs at the BPPS and the LPS
and LNG Terminal will generate minimal quantity of waste and no adverse
environmental impacts will arise with the implementation of standard waste
management practices, waste monitoring and audit programme
for the operation phase of the facilities will not be required.
With
the implementation of good site practices,
adverse environmental impacts (including potential hazards, dust and odour
emissions, noise and wastewater discharge) arising from the management and
disposal of waste during the construction phase and the operation phase are not
anticipated.
The estimated waste arising and the recommend waste
management arrangements during the construction phase and operations phase of
the Project are summarised in Table 8.5.
Options will be further developed and
evaluated to reduce waste generation and to enhance re-use and recycling of
waste generated during the construction and operation phases of the Project.
Table
8.5 Summary
of Estimated Waste Arisings and Recommended Waste Management Arrangements
|
Types of Waste |
Approximate Quantity (a) |
Disposal Locations |
|
|
Construction Phase |
|
|
|
|
Marine sediments |
Total: 0.35Mm3 (in situ
volume): Category L sediment: 0.03Mm3 Category M sediment which passed the
biological screening test: 0.32Mm3 |
Category L
sediment – to be disposed of at open sea disposal site managed by the CEDD Category M
sediment which passed the biological screening test - to be disposed of at Type 1 Open Sea (Dedicated Sites) The disposal sites
are to be allocated by MFC/
CEDD under the PNAP ADV-21. The
project proponent will implement the project in accordance with the DASO and
the requirements as stipulated in PNAP ADV-21,
prior to the application and allocation of space for dredging and disposal of
sediment arising from the project.
|
|
|
C&D materials |
Total: 45,000m3 Inert: 40,500m3 Non-inert: 4,500m3 |
Public fill:
Public fill reception facilities directly or Outlying
Island Transfer Facilities Non-inert C&D materials: WENT Landfill
directly or via Outlying Island Transfer Facilities |
|
|
Chemical waste |
Few hundred litres per month |
CWTC or other
licensed chemical waste treatment facilities |
|
|
General refuse, including floating refuse |
390kg per day |
Recyclable materials: on-site sorting
and off-site recycling Non-recyclable
refuse: WENT Landfill directly or via Outlying
Island Transfer Facilities |
|
|
Operation Phase |
|
|
|
|
Industrial waste |
Insignificant quantity |
Recyclable materials: on-site sorting
and off-site recycling Non-recyclable
refuse: WENT Landfill directly or via Outlying
Island Transfer Facilities |
|
|
Marine sediment from maintenance dredging |
Subjected to site conditions |
Marine disposal
site to be allocated by the MFC/CEDD based on the sediment quality |
|
|
Chemical waste |
Insignificant quantity |
CWTC or other
licensed chemical waste recycling or treatment facilities |
|
|
General refuse, including floating refuse |
32.5kg per day |
Recyclable materials: on-site sorting
and off-site recycling Non-recyclable
refuse: WENT Landfill directly or via Outlying
Island Transfer Facilities |
|
([1]) ”Construction waste” 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) should be
re-used at public fill reception facilities. The rock and concrete can be crushed and
processed to produce 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.
([2])
In accordance with PNAP
ADV-21, the sediment is classified into three categories based on its
contamination levels:
·
Category
L: Sediment with all contaminant levels not exceeding the Lower Chemical
Exceedance Level (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
: Any one or more contaminants in the sediment exceeding the LCEL with none
exceeding the Upper Chemical Exceedance Level (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: 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.
([3])
The analytical results
of some sediment sampling locations proposed in the MSSTP were not assessed as
they are located along the non-dredged pipeline sections.
([4])
Ove Arup & Partners
Hong Kong Ltd (2008) Agreement No. FM 01/2007 – Review of Options for Management of
Contaminated Sediment in Hong Kong.
Report on Assessment of Management Options Final Report (RevA). August
2008