10.1.1
This Section provides an
evaluation of the potential waste management implications associated with the
construction and operation of the Project. Mitigation measures have been
proposed if considered necessary.
10.2.1
The criteria and guidelines for
evaluating potential waste management implications are laid out in Annexes 7
and 15 of the Technical Memorandum on EIA Process (EIAO-TM) under the Environmental
Impact Assessment Ordinance (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 Project.
n Waste Disposal
Ordinance (Cap.354);
n Waste Disposal
(Chemical Waste) (General) Regulation (Cap 354C);
n Waste Disposal
(Charges for Disposal of Construction Waste) Regulation (Cap. 354N);
n Land
(Miscellaneous Provisions) Ordinance (Cap.28);
n Public Health
and Municipal Services Ordinance (Cap.132) – Public Cleansing and Prevention of
Nuisances Regulation; and
n Dumping at Sea
Ordinance (Cap.466)
Waste Disposal
Ordinance (Cap.354)
10.2.2
The Waste
Disposal Ordinance (WDO) prohibits the unauthorised disposal of wastes.
Construction waste is defined under Cap. 354N of the WDO as any substance,
matter or thing that is generated and abandoned from construction works
regardless if it has been processed or stockpiled before being abandoned,
excluding sludge, screenings or any matter removed or generated from
desludging, desilting or dredging works. Under WDO, waste can be disposed of
only at designated waste disposal facilities licensed by the Environmental
Protection Department (EPD).
Waste Disposal
(Chemical Waste) (General) Regulation (Cap.354C)
10.2.3
Issued
under the WDO, the Waste Disposal (Chemical Waste) (General) Regulation
administers the possession, storage, collection, transport and disposal of
chemical wastes. EPD has also issued three guidelines detailing how the
Contractor should comply with the regulations on chemical wastes, namely A
Guide to the Chemical Waste Control Scheme (2016), A Guide to the Registration
of Chemical Waste Producers (2016) and Code of Practice on the Packaging,
Labelling and Storage of Chemical Wastes (1992).
Waste Disposal
(Charges for Disposal of Construction Waste) Regulation (Cap.354N)
10.2.4
Under the Waste Disposal
(Charges for Disposal of Construction Waste) Regulation enacted in January
2006, construction waste delivered to a landfill for disposal must not contain
more than 50% by weight of inert material. Construction waste delivered to a
sorting facility for disposal must contain more than 50% by weight of inert material,
and construction waste delivered to a Public Fill
Reception Facility (PFRF) for disposal must consist entirely of inert
material.
Land (Miscellaneous Provisions) Ordinance (Cap.28)
10.2.5
The inert Construction and
Demolition (C&D) materials (also called public fill) may be taken to PFRFs. PFRFs usually form part of land
reclamation schemes and are operated by the Civil Engineering and Development
Department (CEDD) and others. The
Land (Miscellaneous Provisions) Ordinance requires that individuals or companies
who deliver inert C&D materials to the PFRFs to obtain Dumping Licenses. The licenses are issued by CEDD under
delegated authority from the Director of Lands.
Public Health and
Municipal Services Ordinance (Cap.132) – Public Cleansing and Prevention of
Nuisances Regulation
10.2.6
This Regulation provides a
further control on the illegal dumping of wastes on unauthorised (unlicensed)
sites.
Dumping at Sea
Ordinance (Cap.466)
10.2.7
The Dumping at Sea Ordinance
(DASO) is to control the disposal of substances and articles at sea and the
dumping of substances and articles in the sea and under the sea-bed, and for
connected purposes. All these operations would require a permit to be issued by
the Director of Environmental Protection (DEP) as the Authority under the
DASO. Before an application of a
marine dumping permit is made, requirements stipulated in ETWB TC(W) No.
34/2002 regarding the sampling, testing and disposal arrangement of
dredged/excavated sediments must be fulfilled.
Other Relevant
Guidelines
10.2.8
Other guideline documents which
detail how the Contractor will comply with the WDO and its associated
regulations include:
n Waste Disposal
Plan for Hong Kong (December 1989), Planning, Environment and Lands Branch
Government Secretariat, Hong Kong Government;
n Works Branch
Technical Circular (WBTC) No. 2/93, Public Dumps;
n WBTC No. 2/93B,
Public Filling Facilities;
n WBTC No. 16/96,
Wet Soil in Public Dumps;
n WBTC Nos. 4/98
and 4/98A, Use of Public Fill in Reclamation and Earth Filling Projects;
n WBTC No.
12/2000, Fill Management;
n WBTC No.
19/2001, Metallic Site Hoardings and Signboards;
n WBTC No.
12/2002, Specification Facilitating the Use of Recycled Aggregates;
n Environment,
Transport and Works Bureau Technical Circular (Works) (ETWB TC(W)) No. 34/2002 Management
of Dredged/Excavated Sediment;
n ETWB TC(W) No.
19/2005 Environmental Management on Construction Site;
n Development
Bureau (DEVB) TC(W) No. 6/2010, Trip Ticket for Disposal of Construction and
Demolition Materials;
n DEVB TC(W) No.
8/2010, Enhanced Specification for Site Cleanliness and Tidiness;
n DEVB TC(W)
No.2/2011, Encouraging the Use of Recycled and Other Green Materials in Public
Works Projects;
n DEVB TC(W) No.
9/2011, Enhanced Control Measures for Management of Public Fill; and
n Hong Kong
Blueprint for Sustainable Use of Resources 2013-2022, Environment Bureau, May
2013;
n Project
Administration Handbook (PAH) for Civil Engineering Works (2020 Edition) – Section 4.1.3 relating to construction and demolition
materials.
10.3.1
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 EIAO-TM and summarized as follows.
n Estimation of
the types and quantities of the wastes to be generated;
n Evaluation of
opportunities for waste reduction, re-use and recycling;
n Identification
of disposal options for each type of waste;
n Assessment of
the potential environmental impacts due to the management of waste with respect
to potential hazards, air and odour emissions, noise, wastewater discharges and
public transport; and
n Assessment of
impacts caused by handling, collection, transportation and re-use /disposal of
wastes.
Construction Phase
10.4.1
The construction activities to
be carried out for the Project include demolition of existing facilities, site
clearance, site formation, excavation, installation of new facilities. The
associated types of waste include:
n Construction
and demolition (C&D) materials;
n Excavated sediments;
n Chemical waste;
and
n General refuse.
Operational Phase
10.4.2
Wastes arising from the
operation of the Project would include:
n Screenings and
grits;
n Dewatered
sludge;
n Chemical waste;
and
n General refuse.
Construction Phase
C&D Materials
10.5.1
C&D materials will be generated from demolition of existing facilities, site clearance, site formation,
excavation, installation of new facilities. The C&D materials may consist of inert
materials such as soil, rock, concrete, brick and asphalt and non-inert
materials comprising metal, timber, paper and plastic. During the planning and
design of the general Project layout, construction method and construction
programme, considerations have been given to minimize the generation of inert
C&D materials and maximize the reuse of these inert C&D materials for construction
works. As described in Section 2, this Project would receive pre-treated food
waste and sewage sludge from other Sewage Treatment Works (STW) for
co-digestion. These pre-treated food waste and sewage sludge are currently not received
in the existing TPSTW. In addition,
the capacity of TPSTW shall be increased from 120,000 m3 /day to
160,000 m3/day to meet the sewage treatment demand. Thus, due to
this Project, more space would be required to accommodate the new co-digestion
and treatment facilities. To minimize the visual impact, the heights of new buildings
/ facilities of this Project shall be similar to that of the surrounding
existing buildings in Tai Po Industrial Estate. Due to the space constraint at existing
TPSTW, utilization of the underground space to accommodate new facilities would
be required. In order to minimize the
usage of underground space (and thus minimize the generation of excavated
material), a piece of government land to the south of the existing TPSTW (1.6
hectares) is proposed to accommodate the new sewage treatment facilities. In
addition, only compact-type sewage treatment technology is proposed at the
proposed expansion site to allow more space at the existing TPSTW for new
facilities and to minimize excavated volume. Furthermore, the construction works
and programme have been designed to allow temporary stockpile of excavated
materials generated on-site for backfilling.
10.5.2
Based on the latest design, the estimated volume of
C&D materials generated from the Project is about 364,620 m3. No imported fill is required for the Project. All C&D materials generated shall be
sorted on site into inert C&D materials and the non-inert C&D materials
two separate portions. The C&D materials, the reusable and/or recyclable
materials shall be recovered before disposal of the waste portion off-site as a
last resort. An estimation of quantity of C&D materials generated during
construction phase is summarized in Table 10.1.
Table 10.1 Estimated
Quantities of C&D Materials during Construction Phase
|
Proposed Works
|
Inert C&D
Material (m3)
|
Non-inert C&D
Material (m3)
|
Total C&D
Material (m3)
|
|
Generated
|
Re-used On-site
|
Disposal
|
Generated
|
Recycled Off-site *
|
Disposal
|
|
Demolition of Existing Treatment Facilities of
TPSTW
(2029-2033)
|
130,740
|
19,610
|
111,130
|
19,380
|
13,560
|
5,820
|
150,120
|
|
Construction of New Facilities
(2025-2036)
|
208,030
|
31,200
|
176,830
|
6,470
|
4,530
|
1,940
|
214,500
|
|
Total
|
338,770
|
50,810
|
287,960
|
25,850
|
18,090
|
7,760
|
364,620
|
Note: * The non-inert waste to be reused off-site
includes wood, plastic, steel and other metals and equipment such as pumps,
valves and instrument generated from the demolition works, which would have a
certain value in the recycling industry.
10.5.3
Approximately 338,770 m3 of inert C&D
materials will be generated. Approximate 15% (about 50,810 m3) inert
C&D materials could be reused on-site as filled material, resulting in
disposal of about 287,960 m3. The surplus inert C&D materials would be
disposed of at designated PFRF (Tuen Mun Area 38 Fill
Bank) for off-site beneficial reuse. Assuming a capacity of 7 m3
per truck, bulk factor of 1.7 and 25 working days a month, it is estimated that
approximate 20 truck trips per day would be required for the disposal of inert
C&D materials. The designated disposal site of inert C&D materials shall be
confirmed with the Public Fill Committee of CEDD. A Construction and Demolition
Material Management Plan (C&DMMP) will be prepared and submitted to Public
Fill Committee for approval in accordance with Project Administration Handbook
for Civil Engineering Works. The control measures proposed in Section 10.6 shall be followed for the
management of inert C&D materials.
10.5.4
Approximately
25,850 m3 of non-inert C&D materials will be generated. Such materials will be sorted for reuse and recycling as far as possible
before disposal to landfill. The estimated non-inert C&D materials
recycling rate would be up to 70%. It is estimated that 18,090 m3 of
the non-inert C&D materials would be recycled, resulting in disposal of about 7,760 m3. The non-recyclable
non-inert C&D materials would be disposed of at North
East New Territories (NENT) Landfill. The designated disposal site of non-inert C&D materials shall be
confirmed with the EPD. The separated recyclable non-inert C&D materials
shall be collected by recycling companies for off-site reuse or recycling. The control measures proposed in Section 10.6 shall be followed for the
management of non-inert C&D materials.
Excavated Sediments
10.5.5
The Project site (including the existing TPSTW site and the proposed
expansion site) was formed via land reclamation during the 1970s. It is comprised of general fill
over-lying a layer of marine deposit
or alluvium. The public fill was previously placed on top of the marine
deposits during the 1970s as a result of the land reclamation activities. The past GI data indicated that the majority
of the marine deposits in the Project site would occur at a vertical level of
over 13m below ground level (bgl). The
land-based sediment (marine deposit) layer could potentially be encountered in
some of the proposed excavation works areas of the Project. According to the preliminary design,
approximately 26,200 m3 of excavated
sediments would be generated during the construction of new facilities of the
Project within the period from 2025 to 2036.
10.5.6
A Sediment Sampling and Testing Methodology
Paper (SSTMP) was prepared with reference to ETWB TC(W) No. 34/2002 to present
the sampling and testing requirements for the Project. The SSTMP is given in Appendix
10.1, which was accepted by EPD in October 2021.
10.5.7
Sediment sampling and testing was undertaken during
the period from December 2021 to April 2022 in accordance with the SSTMP except
that the sampling locations have been adjusted due to actual site constraints.
10.5.8
Three sampling locations, namely BH1, BH2 and
BH3, were proposed in the SSTMP. Sampling at BH1 was terminated at less than 1m
bgl due to encountering hard material. Attempts to sampling were made at three
other alternative locations near BH1 but also unsuccessful due to the same
reason. No other feasible sampling locations could be identified at or near the
sampling grid of BH1 due to site constraints (e.g. with underground utilities).
Sampling locations BH2 and BH3 were relocated to 26m north and 11m south of
their original proposed locations in SSTMP respectively due to similar site
constraints. The as-built sediment sampling locations are indicated in Appendix
10.2.
10.5.9
Chemical and biological screening of sediment
samples were conducted in accordance with SSTMP and ETWB TC(W) No. 34/2002. A
total of 6 samples had been collected from the sampling locations and tested
for chemical screening. The details chemical screening results are provided in Appendix
10.3.
10.5.10
Based on the chemical screening results,
Category H sediment was identified in 1 sample at BH3 with Lead exceeded the
UCEL but below 10 times of the LCEL. Category M sediment was identified in 5
samples at BH2/BH3 with Lead exceeded the LCEL but below the UCEL.
10.5.11
Based on the chemical screening results, Tier
III biological screening were conducted on the 5 Category M sediment
samples. All the samples had passed
the biological screening. The results of the biological screening are provided
in Appendix
10.3.
10.5.12
The excavated sediments were classified based
on their contaminant levels with reference to ETWB TC(W) No. 34/2002 as
summarized in Table 10.2. If the estimated excavation depth of each building/facilities is
lower than the termination depth of general fill layer of the nearest ground
investigation (GI) point indicated in Figure 3.1 of Appendix
10.1, occurrence of excavated sediment would be anticipated. With the
assumption of the layer between of the excavation depth and termination depth
of general fill layer to be marine deposit, the quantity of excavated sediment
for each building / facility has been estimated (i.e. excavation area (m2)
× thickness of marine deposit (m)). The total volume of sediment generated was
estimated to be approximately 26,200 m3. The quantity for each
sediment category is estimated in pro rata basis according to categorization of
the samples in the sediment sampling and testing.
Table 10.2 Estimated
Quantities of Sediment under each Disposal Option
|
Disposal Option
|
Corresponding Category
|
Estimated In-situ
Quantity* (m3)
|
|
Timing (2025 - 2036)
|
|
Type 1 – Open Sea Disposal
|
Category L Sediment
|
0
|
|
Type 1 – Open Sea Disposal (Dedicated Sites)
|
Category M Sediment (passed the biological
screening)
|
21,800
|
|
Type 2 – Confined Marine Disposal at disposal
site(s)
|
Category H Sediment and H+ Sediment (passed the
biological screening)
|
4,400
|
|
Type 3 – Special
Treatment/ Disposal
|
Category H+ Sediment
(failed biological screening)
|
0
|
|
Total:
|
26,200
|
Note: *The quantities
shown in the table are estimates only and will be subject to further review
during the detailed design and construction stage.
10.5.13
The excavated sediments would be disposed of to
the designated marine disposal areas in accordance with
the requirements of the ETWB TC(W) No. 34/2002. The proposed disposal
outlets of the Type 1 (Dedicated Sites) and Type 2 sediments would be South
Cheung Chau / East Ninepin and East Sha Chau, respectively. The final disposal
sites of the excavated sediments shall be confirmed with Marine Fill Committee
(MFC). The proposed Mitigation and control requirements for excavated sediments
are given in Section 10.6. Provided
that the handling of excavated sediments is in accordance with the procedures in
ETWB TC(W) No. 34/2002 and the recommendations in this EIA, the potential waste
management implications on the environment associated with handling of
excavated sediment during the construction phase of the Project are not
expected.
10.5.14
The sediment sampling and testing results and
disposal options presented in this report only serve the purpose of fulfilling
this EIA Study under the EIAO. Separate submissions (e.g. Sediment Sampling and
Testing Plan (SSTP) / Sediment Quality Report (SQR)) should be submitted to
EPD’s Marine Dumping Control Section / Territorial Control Office and to obtain
MFC’s agreement on the dredging rationale and disposal arrangement for marine
disposal under the DASO.
Chemical Waste
10.5.15
Wastes classified as chemical waste are
listed in the Waste Disposal (Chemical Waste) (General) Regulation. Where the
construction processes produce chemical waste, the contractor must register
with EPD as a chemical waste producer. In general, chemical waste would mainly
arise from maintenance of construction equipment. These may include the
following items:
n Scarp batteries
or spent acid/alkali from their maintenance;
n Used engine
oils, hydraulic fluids and waste fuel;
n Spent mineral
oils/cleaning fluids from mechanical machinery; and
n Spent
solvents/solutions from equipment cleaning activities.
10.5.16 Accidental
spillages of chemicals in the works area may contaminate the top soils on
exposed ground/earth. The contaminated soil particles may be washed away by
construction site runoff causes water pollution.
10.5.17 Chemical
wastes pose environmental and health and safety hazards if not stored and
disposed of in an appropriate manner as outlined in the Waste Disposal
(Chemical Waste) (General) Regulation.
These hazards include:
n Toxic effects
to workers;
n Adverse effects
on water quality from spills; and
n Fire hazards.
10.5.18 The
amount of chemical waste cannot be accurately predicted at this stage since it
largely depends on the contractor’s housekeeping measure. The amount is anticipated to be small
(about 50 litres per month) and it is recommended that good housekeeping
measures should be implemented to reduce the amount of chemical waste
generated. The chemical wastes will be collected by licensed collector for the
disposal of at licensed treatment facilities (i.e. Chemical Waste Treatment
Centre (CWTC) at Tsing Yi) in accordance with relevant regulation and
guideline.
10.5.19 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 unacceptable environmental impacts and hazards will result from the
handling, transportation and disposal of chemical waste arising from the
Project. The control measures proposed in Section
10.6 shall be followed for the management of chemical waste.
General Refuse
10.5.20
General refuse will be generated by the site
staff and construction workers during the construction period. This includes
food scraps, aluminum cans, waste papers, plastic containers, food packaging,
etc. The amount of general refuse that may be produced is dependent on size of
workforce at site.
10.5.21
Based on a construction workforce of 400 persons
(typical number for construction in similar scale) and assuming a general
refuse generation rate of 0.65 kg per worker per day, the amount of general
refuse to be generated on site will be about 260 kg per day. The general refuse
generated will be collected by a waste collector and disposed of at waste
transfer/disposal facilities and then to landfill.
10.5.22
The storage of general refuse has the
potential to give rise to a variety of adverse environmental impacts. These
include odour if waste is not collected frequently, water quality impacts if
waste enters water bodies and visual impact from windblown litters. The refuse
may attract pests and vermin if the storage areas are not well maintained and
cleaned regularly. In addition, disposal of waste at sites other than approved
waste transfer or disposal facilities can also lead to environmental impacts.
10.5.23
Handling and disposal of general refuse
should cope with the presence of peak workforce during the construction period.
Provided that the refuse is stored and transported in accordance with proper
practices and disposed at approved disposal facilities, potential environmental
impact is not expected. The control measures proposed in Section 10.6 shall be followed for the management of general
refuse.
10.5.24
The proposed disposal outlets and tentative
transportation routings for the disposal of various types of waste during construction
phase are shown in Table 10.3.
Table 10.3 Proposed Disposal Outlet and Tentative Transportation
Routings for Waste Disposal during Construction Phase
|
Types of Waste
|
Estimated Generation
Amount (Timing of Generation)
|
Handling
|
Proposed Disposal Outlet
|
Estimated Frequency of
Truck
|
Tentative Transportation
Routing
|
|
Inert C&D Materials
|
338,770 m3
(2025 to 2036)
|
The inert C&D materials generated would be sorted and reused
on-site as far as practicable;
50,810 m3 of inert C&D material to be reused on-site.
|
287,960 m3 of inert
C&D material to be disposed at Tuen Mun Area 38 Fill Bank for other
beneficial uses
|
20 truck trips per day
|
via Ting Kok Road,
Fanling Highway, San Tin Highway, Yuen Long Highway, Tuen Mun Road, Wong Chu
Road, Lung Fu Road, Lung Mun Road
|
|
Non-inert C&D
Materials
|
25,850 m3
(2025 to 2036)
|
Any recyclable materials (e.g., metal) will be segregated from
the non-inert C&D materials for recycle;
18,090 m3 of non-inert C&D material to be recycled off-site.
|
7,760 m3 of
non-inert C&D material or if rejected by recycling companies as the last
resort to NENT Landfill
|
Not more than 1 truck
trip per day
|
via Ting Kok Road,
Fanling Highway, Jockey Club Road, Man Kam To Road, Wo Keng Shan Road
|
|
Excavated Sediments
|
Category M Sediment
(passed biological screening)
|
21,800 m3 (2025 to 2036)
|
To be handled with mitigation measures as per Sections 10.6.15 to 10.6.23
|
Type 1 - Open Sea Disposal
(Dedicated Site) at South Cheung Chau / East Ninepin
|
Not more than 2 truck
trip per day
|
via Ting Kok Road, Tolo
Highway, Tai Po Road (Sha Tin), Tsing Sha Highway, Lin Cheung Road, Yuen Fat Wharf
(for barging)
|
|
Category H Sediment
|
4,400 m3
(2025 to 2036)
|
Type 2 – Confined Marine
Disposal at East Sha Chau
|
Not more than 1 truck
trip per day
|
|
Chemical Waste
|
50 litres per month
(2025 to 2036)
|
Provide on-site chemical waste collection points for collection
by licensed collector
|
To CWTC
|
As required
|
via Ting Kok Road, Tolo
Highway, Tai Po Road (Sha Tin), Tsing Sha Highway, Tsing Yi Road
|
|
General Refuse
|
260 kg per day
(2025 to 2036)
|
Provide on-site refuse collection points
|
To NENT Landfill
|
Not more than 1 truck
trip per day
|
via Ting Kok Road,
Fanling Highway, Jockey Club Road, Man Kam To Road, Wo Keng Shan Road
|
Operational Phase
Screenings and Grits
10.5.25
Screening and grits would be generated at the
inlet works during the operation of the upgraded TPSTW.
The estimated total volume of screening and grits to be generated would be 43 m3
per day. The generated screenings and grits would be compacted and stored
properly in a covered container. The screenings and grits would be collected
and transported by waste collector for disposed of at NENT landfill. A
reputable waste collector would be employed by the operators to minimize the
potential pest and odour impacts.
Dewatered Sludge
10.5.26
Primary sewage sludge and activated sewage
sludge will be generated from primary sedimentation and secondary treatment,
respectively. Imported sludge from other STWs and pre-treated food waste will
be received at truck unloading facilities. The sludge generated from the
upgraded TPSTW and imported from other STWs will be co-digested with the imported
pre-treated food waste. The imported sludge / pre-treated food waste will be
transported by fully enclosed pipes or trucks to reduce odour nuisance.
10.5.27
The generated/imported sludge as well as the
imported pre-treated food waste will be pumped to digester battery for
co-digestion. The digestate generated from co-digestion would
be dewatered to dry solid content of 30% (i.e. dewatered sludge) before
disposal. The estimated
quantity of dewatered sludge generated from the upgraded TPSTW would be
approximately 469 tonne per day (i.e. 586
m3 per day with assumption of the density of 800kg/m3).
The dewatered sludge would be stored properly in covered containers within the
TPSTW and then delivered to the T· Park at Tuen Mun for disposal. With assumption of truck capacity of 12 tonne, it is estimated that approximate 40 truck trips per day would be required
for the disposal.
Chemical Waste
10.5.28
Small quantities of chemical wastes including
about 200 no. of spent UV lamps, about 9,000 litres (L) of spent lubricants, about
320 L of spent cleaning solvent and about 4 no. of used batteries would be generated
from regular maintenance activities per year during the operational phase. The
chemical wastes generated may pose environmental and health and safety hazards
if not stored and disposed properly as outlined in the Waste Disposal (Chemical
Waste) (General) Regulation The operator shall register with EPD as a chemical
waste producer if any chemical waste would be generated from the operation. The
chemical wastes generated during operation of the Project will be collected by
licensed collector for the disposal of at licensed treatment facilities (i.e.
CWTC at Tsing Yi).
General Refuse
10.5.29 General refuse, such as paper,
food waste, plastic, aluminum cans, packaging and office wastes etc., would be
generated by staff, visitors, and office activities during operation of the
Project. It is expected 240 site staff
will be working on site during the operational phase. Assuming a general refuse
generation rate of 0.65 kg per person per day, the amount of general refuse to
be generated from the Project will be about 156 kg per day. The general refuse
generated will be collected by a waste collector and disposed of at waste
transfer/disposal facilities and then to landfill.
10.5.30
The proposed disposal outlets and tentative
transportation routings for the disposal of various types of waste during operational
phase are shown in Table 10.4.
Table 10.4 Proposed Disposal Outlet and Tentative
Transportation Routings for Waste Disposal during Operational Phase
|
Types of Waste
|
Estimated Generation Amount (Timing of Generation)
|
Handling
|
Proposed Disposal Outlet
|
Estimated Frequency of Truck
|
Tentative Transportation Routing
|
|
Screenings and Grits
|
43 m3 per day
(from 2036 onwards)
|
To be compacted and stored in a covered container for collection
by waste collector
|
To NENT Landfill
|
7 truck trip per day
|
via Ting Kok Road, Fanling Highway, Jockey Club Road, Man Kam To Road,
Wo Keng Shan Road
|
|
Dewatered Sludge
|
586
m3 per day
(from 2036 onwards)
|
To be stored properly in covered
containers
|
To T· Park
|
40 truck trips per day
|
via Ting Kok Road, Tai Po Road, Lam Kam Road, Kam Tin Road, Yuen Long
Highway, Tuen Mun Road, Lung Mun Road, Nim Wan Road
|
|
Chemical Waste
|
Spent UV lamps -200 no. per
year;
Spent lubricants – 9,000 L
per year; Spent cleaning solvent – 320 L per year;
Used batteries – 4 no. per
year
(from 2036 onwards)
|
Provide on-site chemical waste
collection points for collection by licensed collector
|
To CWTC
|
As required
|
via Ting Kok Road, Tolo Highway, Tai Po Road (Sha Tin), Tsing Sha
Highway, Tsing Yi Road
|
|
General Refuse
|
156 kg per day
(from 2036 onwards)
|
Provide on-site refuse collection
points
|
To NENT Landfill
|
Not more than 1 truck trip per day
|
via Ting Kok Road, Fanling Highway, Jockey Club Road, Man Kam To Road,
Wo Keng Shan Road
|
Construction Phase
General
10.6.1
The management of C&D materials follows
the same hierarchy as for other wastes i.e. in order of desirability: avoidance, minimization, reuse/recycling,
treatment and safe disposal of waste.
10.6.2
Training of construction staff should be
undertaken by the contractor about the concept of site cleanliness and
appropriate waste management procedures.
The contractor should develop and provide toolbox talk for on-site sorting of C&D
materials to enhance workers’ awareness in handling, sorting, reuse and
recycling of C&D materials.
Requirements for staff training should be included in the contractor’s
Environmental Management Plan (EMP). The EMP shall be submitted to the Engineer
for approval before construction works in accordance with ETWB TC(W) No. 19/2005.
10.6.3
Good planning and site management practice
should be employed to eliminate over ordering or mixing of construction materials to reduce wastage. Proper storage and site practices will
minimize the damage or contamination of construction materials.
10.6.4
Where waste generation is unavoidable, the
potential for recycling or reuse should be rigorously explored. If waste cannot be recycled, disposal
routes described in the EMP shall be followed. A recording system for the amount of
wastes generated, recycled and disposed (including the disposal sites) should
be implemented. In order to monitor
the disposal of C&D material and solid wastes at public filling facilities
and landfills and to control fly-tipping, a trip-ticket system should be
included. DEVB TC(W) No. 6/2010
shall be referenced for details.
10.6.5
Regular cleaning and maintenance of the waste
storage area should be provided.
Best Management Practice
10.6.6
The proposed mitigation measures are as
below:
n
An on-site
environmental coordinator should be identified at the outset of the
works. The EMP incorporating waste management shall be prepared in accordance with the requirements set out
in the ETWB TC(W) No. 19/2005. The EMP shall include monthly and yearly Waste
Flow Tables (WFT) that indicate the amounts of waste generated, recycled and
disposed of (including final disposal site), and which shall be regularly
updated;
n The
reuse/recycling of all materials on site shall be investigated
prior to treatment/ disposal off-site;
n Good site
practices shall be adopted from the commencement of works to avoid the
generation of waste, reduce cross contamination of waste and to promote waste minimization;
n All waste materials shall be sorted
on-site into inert and non-inert C&D materials, and where the materials can
be recycled or reused, they shall be further segregated. Inert
C&D materials will comprise stone, rock, masonry, brick, concrete and soil
which is suitable for land reclamation and site formation whilst non-inert C&D
materials include all other wastes generated from the construction process such
as plastic packaging and vegetation (from site clearance);
n The contractor
shall be responsible for identifying what materials can be recycled/ reused,
whether on-site or off-site. In the event of the latter, the contractor shall
make arrangements for the collection of the recyclable
materials. Any remaining non-inert C&D materials shall be
collected and disposed of to the landfills whilst any inert C&D materials shall be re-used on site as far as possible. Alternatively, if
inert C&D materials cannot be reused on-site, the materials would be
delivered to PFRFs for beneficial reuse after obtaining the appropriate license;
n With reference to DEVB TC(W)
No.6/2010, a trip ticket system should be established at the outset of the
construction to monitor the disposal of C&D materials and solid wastes from
the site to public filling facilities and landfills;
n Under the Waste
Disposal (Chemical Waste) (General) Regulation, the Contractor shall register
as a Chemical Waste Producer if chemical wastes such as spent lubricants and
paints are generated on site. Only licensed chemical waste collectors shall be
employed to collect any chemical waste generated at site. The handling,
storage, transportation and disposal of chemical wastes shall be conducted in accordance with
the Code of Practice on the Packaging, Labelling and Storage of Chemical Wastes
and A Guide to the Chemical Waste Control Scheme both published by EPD;
n A sufficient number of covered bins
shall be provided on site for the containment of general refuse to prevent visual impacts and
nuisance to the sensitive surroundings. These bins shall be cleared
daily and the collected waste disposed of to the refuse transfer station.
Further to the issue of DEVB TC(W) No. 8/2010, the contractor is required to
maintain a clean and hygienic site throughout the Project works; and
n The contractor shall comply with all relevant statutory
requirements and guidelines and their updated versions that may be issued
during the course of Project construction.
On-site Sorting, Reuse
and Recycling
10.6.7
All waste materials should be segregated into
categories covering:
n Inert C&D
materials suitable for reuse on-site;
n Inert C&D
materials suitable for PFRFs;
n Recyclable
non-inert C&D materials for recycling;
n Remaining
non-inert C&D materials for landfill;
n Chemical waste;
and
n General refuse
for landfill.
10.6.8
Proper segregation and disposal of
construction waste should be implemented. Separate containers should be
provided for inert and non-inert C&D materials.
10.6.9
Sorting is important to recover materials for
reuse and recycling. Specific area
should be allocated for on-site sorting of C&D materials and to provide a
temporary storage area for those sorted materials. If area is limited, all C&D
materials should at least be sorted on-site into inert and non-inert
components. Non-inert C&D materials such as bamboo, timber, vegetation,
packaging waste and other organic materials should be reused and recycled to
local recycler wherever possible and disposed to the designated landfill only
as a last resort. Inert C&D
materials such as concrete, stone, clay, brick, soil, asphalt and the like
should be separated and reused in this or other projects (subject to approval
by the relevant parties in accordance with the DEVB TC(W) No. 6/2010) before
disposed of at a public filling facility operated by CEDD. Steel and other metals should be
recovered from demolition waste stream and recycled.
Construction and Demolition Material
10.6.10
Inert C&D materials should be temporarily
stored on-site for use as backfill as far as possible. It should be properly
covered with tarpaulin or similar impervious sheeting to prevent dust nuisance
and site runoff. Surplus inert C&D materials should be disposed of at PFRFs.
10.6.11 Control
measures for temporary stockpiles on-site should be taken in order to minimize
the noise, generation of dust, pollution of water and visual impact. These measures include:
n Surface of
stockpiled soil should be regularly wetted with water especially during dry
season;
n Disturbance of
stockpiled soil should be minimized;
n Stockpiled soil
should be properly covered with tarpaulin especially when heavy rain storms are
predicted;
n Stockpiling
areas should be enclosed where space is available;
n Stockpiling
location should be away from the water bodies; and
n An independent
surface water drainage system equipped with silt traps should be installed at
the stockpiling area.
10.6.12 The
Public Fill Committee of CEDD should be consulted for disposal of inert C&D
materials to PFRFs while EPD should be consulted for disposal
of non-inert C&D materials to landfill. Disposal of C&D materials to
landfill must not have more than 50% (by weight) inert material. The C&D materials delivered for
landfill disposal should contain no free water and the liquid content should
not exceed 70% by weight.
10.6.13 In
order to avoid dust impacts, any vehicle leaving a works area carrying inert or
non-inert C&D materials should have their load covered up before leaving
the construction site.
10.6.14 C&D
materials should be disposed of at designated PFRFs or landfills. Disposal of these materials for the use
at other construction projects is subject to the approval of the Engineer
and/or other relevant reception authorities. Furthermore, unauthorized disposal of
C&D materials in particular on private agricultural land is prohibited and
may be subject to relevant enforcement and regulating actions. The disposal of C&D materials will
be controlled through trip-ticket system in accordance with DEVB TC(W) No.
6/2010.
Excavated Sediments
10.6.16 Requirements
of the Air Pollution Control (Construction Dust) Regulation, where relevant,
shall be adhered to during excavation, transportation and disposal of the
sediment.
10.6.17 In
order to minimize the exposure to contaminated materials, workers shall, if
necessary, wear appropriate personal protective equipment (PPE) when handling
contaminated sediments. Adequate
washing and cleaning facilities shall also be provided on site.
10.6.18 For
off-site disposal, the requirements and procedures specified under ETWB TC(W)
No. 34/2002 shall be followed. MFC of CEDD is managing the disposal facilities
in Hong Kong for the excavated sediment, while EPD is the authority of issuing
marine dumping permit under the DASO.
10.6.19 To
ensure disposal space is allocated for the Project, the Project Proponent
should be responsible for obtaining agreement from MFC on the rationale for
sediment removal and the allocation of the disposal site. The contractor(s), on
the other hand, should be responsible for the application of the marine dumping
permit under DASO from EPD for the sediment disposal.
10.6.20 The
excavated sediments are expected to be loaded onto the barge at public barging
point of which the exact location will be determined by the contractor(s) and
agreed by EPD/CEDD and transported to the designated disposal sites allocated
by MFC. The excavated sediment
would be disposed of according to its determined disposal options and ETWB
TC(W) No. 34/2002.
10.6.21 Stockpiling
of contaminated sediments should be avoided as far as possible. If temporary stockpiling of contaminated
sediments is necessary, the excavated sediment should be covered by tarpaulin
and the area should be placed within earth bunds or sand bags to prevent
leachate from entering the ground, nearby drains and surrounding water
bodies. The stockpiling areas for
contaminated sediments should be paved with impermeable linings to avoid
contamination to underlying soil or groundwater. Separate and clearly defined areas
should be provided for stockpiling of contaminated and uncontaminated
materials. Leachate, if any, should be collected and discharged according to
the Water Pollution Control Ordinance (WPCO).
10.6.22 In
order to minimize the potential odour / dust emissions during excavation and
transportation of the sediment, the excavated sediments shall be wetted during
excavation / material handling and shall be properly covered when placed on
trucks or barges. Loading of the
excavated sediment to the barge shall be controlled to avoid splashing and
overflowing of the sediment slurry to the surrounding water.
Chemical Waste
10.6.24
Should any chemical waste be generated, the
contractor/operator must register with EPD as a chemical waste producer. Wastes classified as chemical wastes are
listed in the Waste Disposal (Chemical Waste) (General) Regulation. These
wastes are subject to stringent disposal routes. EPD requires information on the
particulars of the waste generation processes including the types of waste
produced, their location, quantities and generation rates. An updated list of
licensed chemical waste collector can be obtained from EPD.
10.6.25 Storage,
handling, transport and disposal of chemical waste should be arranged in
accordance with the Code of Practice on the Packaging, Labelling and Storage of
Chemical Wastes published by EPD, and should be collected by a licensed
chemical waste collector.
10.6.26 Suitable
containers should be used for specific types of chemical wastes. The containers
should be properly labelled (in English and Chinese in accordance with
instructions prescribed in Schedule 2 of the Regulations), resistance to
corrosion, stored safely and closely secured. Stored volume should not be kept more
than 450 liters unless the specification has been approved by the EPD.
Storage area should be enclosed by three sides by a wall, partition of
fence that is at least 2 m height or height of tallest container with adequate
ventilation and space.
10.6.27 Hard
standing, impermeable surfaces draining via oil interceptors should be provided
in works area compounds.
Interceptors should be regularly emptied to prevent release of oils and
grease into the surface water drainage system after accidental spillages. The interceptor should have a bypass to
prevent flushing during periods of heavy rain. Oil and fuel bunkers should be bunded
and/or enclosed on three sides to prevent discharge due to accidental spillages
or breaches of tanks. Bunding
should be of sufficient capacity to accommodate 110% of the volume of the
largest container or 20% of the total volume of waste, whichever is largest. Waste collected from any oil
interceptors should be collected and disposed of by a licensed collector.
10.6.28 Lubricants,
waste oils and other chemical wastes are likely to be generated during the
maintenance of vehicles and mechanical equipment. Used lubricants should be collected and
stored in individual containers which are fully labelled in English and Chinese
and stored in a designated secure place.
The chemical waste shall be collected by licensed chemical waste
collectors.
10.6.29 The
registered chemical waste producer (i.e. the contractor) has to arrange for the
chemical waste to be collected by licensed collectors. The licensed collector should regularly
take chemical waste to a licensed chemical waste treatment facility (such as
the CWTC in Tsing Yi). A trip
ticket system operates to control the movement of chemical wastes.
10.6.30 No
lubricants, oils, solvents or paint products should be allowed to discharge
into water courses, either by direct discharge, or as contaminants carried in
surface water runoff from the construction site.
General Refuse
10.6.31 General
refuse should be disposed of to landfill as designated by EPD only after
recyclable materials (e.g. paper, metals, aluminum cans, etc.) have been sorted
out.
10.6.32 The
contractor should nominate approved site 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 about site cleanliness, proper waste management and chemical handling
procedures should be provided. Recyclable materials such as papers and aluminum
cans should be separated and delivered to the local recyclers. An adequate
number of waste containers should be provided to avoid spillage of waste.
10.6.33 General
refuse generated on-site should be stored in enclosed bins or skips and
collected separately from other construction and chemical wastes and disposed
of at designated landfill by reputable waste collector. The removal of waste
from the site should be arranged on a daily basis or at least on every second
day by the contractor to minimize any potential odour impacts, minimize the
presence of pests, vermin and other scavengers and prevent unsightly
accumulation of waste.
Operational Phase
Screenings, Grits and
Dewatered Sludge
Chemical Waste and
General Refuse
10.6.35
The chemical waste and general
refuse generated during the operational phase would follow the same handling
procedures and disposal method presented in Sections 10.6.24 to 10.6.33.
It is expected that there would be limited quantities of chemical waste and
general refuse to be generated from the operation of the Project and will be
properly handled by licensed chemical waste collectors and reputable waste
collector.
10.7.1
With the implementation of proper waste
management practices for storage, handling, transportation and disposal of
waste arisings, no adverse residual impacts are expected during the
construction and operational phases of the Project.
10.8.1
No monitoring is required during construction
phase. Weekly audit of waste management practice is recommended during the
construction phase of the Project to determine if waste is being managed in
accordance with prescribed waste management procedures and the EMP. The audits
should examine all aspects of waste management including waste generation,
storage, recycling, treatment, transportation, and disposal.
10.8.2
No monitoring and audit is considered
required during the operational phase of the Project.
10.9.1
C&D materials will inevitably be produced during the construction phase of
the Project. Waste generated during construction works include inert C&D
materials, non-inert C&D materials, chemical waste and general refuse.
Approximately 338,770 m3 of inert C&D materials would be
generated of which 50,810 m3 would be reused on-site and 287,960 m3
would be disposed of at designated PFRF. Approximately 25,850 m3 of non-inert C&D materials
would be generated of which 18,090 m3 would be recycled and 7,760 m3
would be disposed of at designated landfill. Approximately 26,200 m3 of excavated sediments would be generated during
construction phase and the excavated sediment would be disposed of in
accordance with ETWB TC(W) No. 34/2002. It is estimated that about 50 litres of chemical waste would be
generated per month and collected by licensed chemical waste collector for
disposal at licensed treatment facilities. About 260 kg of general refuse would
be generated per day and collected by waste collector for disposal of at waste
transfer/disposal facilities and then to landfill.
10.9.2
During
operational phase, 43 m3 screenings and grits would be generated at
the inlet works per day while 586 m3
dewatered sludge would be generated from sewage treatment and co-digestion per
day. The collected screenings and grits would be disposed of at landfill by a
reputable waste collector while the dewatered sludge/digestate would be
disposed of at T· Park in Tuen Mun.
10.9.3
With
the implementation of the mitigation measures during the construction and
operational phases of the Project, no significant impact on waste management is
anticipated. The implementation of
the mitigation measures shall form part of the works contracts. Regular site
inspections are recommended during construction phase to ensure the measures
are implemented properly.