11
Waste Management Implications
This chapter presents the findings
of the assessment of waste management implications arising from the SCL
(TAW-HUH) during the construction and operational phases. Opportunities for waste
avoidance, minimisation, reuse, recycling and disposal were examined. With the
construction material import/ export balancing design approach and the
appropriate mitigation measures implemented during the different phases of the
Project, potential environmental impacts associated with waste management would
be insignificant.
The waste management implication
assessment has been conducted in accordance with the requirements of Annexes 7
and 15 of the TM-EIAO and Clause 3.4.2 of the EIA Study Brief for the Project.
The
relevant legislation and associated guidance notes relate to the study for the
assessment of waste management implications include:
·
Waste
Disposal (Amendment) Ordinance
(Cap 354) and subsidiary Regulations;
·
Environmental
Impact Assessment Ordinance (Cap 499) and subsidiary Regulations;
·
Dumping at Sea Ordinance (Cap 466);
·
Land
(Miscellaneous Provisions) Ordinance (Cap 28); and
·
Public
Health and Municipal Service Ordinance (Cap 132) – Public Cleansing and
Prevention of Nuisances By-laws.
Under the
Waste Disposal (Amendment) Ordinance, some of the regulations are relevant to
this EIA, including:
• Waste
Disposal (Chemical Waste) (General) Regulation (Cap 354); and
• Waste
Disposal (Charges for Disposal of Construction Waste) Regulation (Cap 354).
11.2.1 Waste Disposal (Amendment) Ordinance
The Waste
Disposal Ordinance (WDO) prohibits unauthorised disposal of wastes.
Construction and Demolition (C&D) waste is not directly defined in the WDO
but is considered as “trade waste” which is defined as waste from any trade,
manufacturer or business, or any wasted building, or civil engineering
materials, but does not include animal waste.
Under the WDO, wastes can only be disposed of at sites licensed by EPD. Breach of these regulations can lead to a fine and/ or imprisonment. The WDO also stipulates the requirements
for issuing licenses for the collection and transportation of wastes. Licenses are however not required for
the collection and transportation of C&D waste or trade waste.
11.2.2 Waste Disposal (Charges for Disposal
of Construction Waste) Regulation
Under the
WDO and the Charging Regulation, wastes can only be disposed of at designated
waste disposal facilities licensed by EPD.
Schedule 5 of Regulation defines that inert construction waste includes
rock, rubble, boulder, earth, soil, sand, concrete, brick, tile, masonry or
used bentonite.
According to
Schedule 6 of the Regulation, 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
for disposal must consist entirely of inert material.
For
construction work with a value of more than HK$1M, the main contractor is
required to establish a billing account at EPD before transporting the
construction waste to the designated waste disposal facilities (eg landfill, public fill etc). The vessels for delivering construction
waste to public fill reception facility would need prior approval from
EPD. Breach of these regulations
can lead to a fine and/or imprisonment.
Depending on the percentage of inert
materials in the construction waste, construction waste can be disposed at
public fill, sorting facilities, landfills and outlying islands transfer
facilities where different disposal cost would be applied. The scheme encourages reducing, reusing
and sorting of construction waste such that the waste producer can minimise
their disposal fee.
11.2.3 Waste Disposal (Chemical Waste)
(General) Regulation
Chemical
waste includes any scrap materials, or unwanted substances specified under
Schedule 1 of this Regulation, if such a substance or chemical occurs in such a
form, quantity or concentration that causes pollution or constitutes a danger
to health or risk of pollution to the environment.
A person
shall not produce, or cause to be produced, chemical wastes unless he is registered
with EPD. Any person who
contravenes this requirement commits an offence and is liable to a fine and/or
imprisonment. Chemical wastes must
be treated, utilising on-site plant licensed by EPD or have a licensed
collector to transport 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 trace wastes from production to disposal.
This
regulation also prescribes the storage facilities to be provided on site
including labelling and warning sign. To minimise the risks of pollution and
danger to human health or life, the waste producer is required to prepare and
make available written emergency procedures for spillage, leakage or accidents
arising from storage of chemical wastes. The waste producer must also provide
employees with training for such procedures.
11.2.4 Dumping at Sea Ordinance
According
to the Dumping at Sea Ordinance, a permit from EPD is required if any waste
producer intend to dump materials from vessels to designated marine dumping
areas. The Authority will consider
a number of factors including sources and nature of materials to be dumped, dumping
rates, need for inspection / testing, water pollution avoidance measures etc
before determining whether such a permit would be granted and, where deemed
necessary, any conditions to be complied with. Breach of the requirements in the permit
would result in a fine and / or to imprisonment.
11.2.5 Land (Miscellaneous Provisions)
Ordinance
The inert
portion of C&D materials may be taken to public filling facilities
including public filling area, public filling barging points and stockpiling
areas. These facilities usually form part of land reclamation schemes and are
operated by CEDD. This ordinance requires Dumping Licenses (to be issued by
CEDD) to be obtained by individuals or companies, who deliver inert C&D
materials to the public filling facilities.
Individual
licenses and windscreen stickers are issued for each vehicle involved. Public filling areas will accept only
inert building debris, soil, rock and broken concrete. There is no size
limitation on the rock and broken concrete, and a small amount of timber mixed
with inert material is permissible. The material should, however, be free from
marine mud, household refuse, plastic, metal, individual and chemical wastes,
animal and vegetable matters and any other materials considered unsuitable by
the Filling Supervisor.
11.2.6 Public Cleansing and Prevention of
Nuisances Regulation
This
regulation provides further control on illegal dumping of litter or waste in
street and public places (including water course, stream, channel etc). Offence of this regulation would result
in a fine and / or to imprisonment.
11.2.7 Other Relevant Guidelines
The
following documents and guidelines also relate to waste management and
disposal:
Table 11.1: Other relevant documents and information
|
Bureau / Department |
Documents / Guidelines / Technical Circulars |
|
ex-Planning,
Environmental and Lands Branch |
·
Waste Disposal Plan for · Waste Reduction Framework Plan, 1998 to 2007 |
|
ex-
Environment, Transport and Works Bureau |
· Works Branch Technical Circular (WBTC) No. 32/92, The Use of Tropical Hard Wood on Construction Site · WBTC No. 2/93, Public Dumps · Works Bureau TC No 2/93B, Public Filling Facilities · WBTC No. 16/96, Wet Soil in Public Dumps · Works Bureau TC Nos. 4/98 and 4/98A, Use of Public Fill in Reclamation and Earth Filling Project · Works Bureau TC Nos. 25/99, 25/99A and 25/99C, Incorporation of Information on Construction and Demolition Material Management in Public Works Sub-committee Papers · Works Bureau TC No. 12/2000, Fill Management · Works Bureau TC No. 19/2001, Metallic Site Hoardings and Signboards · Works Bureau TC No. 06/2002, Enhanced Specification for Site Cleanliness and Tidiness · Works Bureau TC No. 12/2002, Specification Facilitating the Use of Recycled Aggregates · Chapter 4 of the General Guidelines for Management of the Project Administration Handbook (PAH) · ETWBTC (Works) No. 34/2002, Management of Dredged / Excavated Sediment · ETWBTC (Works) No. 19/2005, Environmental Management on Construction Site |
|
DEVB |
· DEVB TC (Works) No 6/2010, Trip-ticket System for Disposal of Construction and Demolition Materials |
|
EPD / CEDD |
· New Disposal Arrangements for Construction Waste (1992) |
|
EPD |
· A Policy Framework for Management of Municipal Solid Waste (2005 -2014), (December 2005) · Code of Practice on the Packaging, Labeling and Storage of Chemical Wastes (1992) |
|
PlanD |
·
|
According to Chapter
4 of the General Guidelines for Management of the Project Administration
Handbook (PAH), for Designated Projects, a Construction &
Demolition Material Management Plan (C&DMMP) has to be submitted to the
Public Fill Committee in case of C&D materials exceed 50,000m3.
ETWBTC
(Works) No. 19/2005, Environmental Management on Construction Site, sets out
the policy, procedures and requirements for contractor to prepare and implement
and enhanced Waste Management Plan, which becomes a part of the Environmental
management Plan in accordance with the aforesaid ETWBTC (Works) No. 19/2005.
11.2.8 Disposal Criteria for Dredged / Excavated Sediment
ETWBTC (Works) No. 34/2002 stipulates the procedures for seeking
approval to dredged/ excavated sediment and the management framework for marine
disposal of such sediment.
Applications for approval of dredging proposal and allocation of marine
disposal shall be made to the Secretary of Marine Fill Committee (MFC). Marine
Dumping Permits as stipulated under the Dumping at Sea Ordinance are required
from EPD for the disposal of dredged sediment. No dredging works is allowed to proceed until
all issues on management of dredged sediments have been resolved and all
relevant arrangements have been endorsed by the relevant authorities including
MFC and EPD. The Project Proponent has regularly provided update information to MFC via
Railway Development Office (RDO) on estimated quantities of sediment disposal
from SCL (TAW – HUH), for reserving the relevant dumping sites allocated by
MFC. Exact location
of marine disposal will be assigned by MFC. The project proponent had obtained
confirmation from MFC on the proposed disposal arrangement before the
commencement of the construction works (see MFC’s letter included in Appendix 11.1).
11.2.9 Landfill Disposal Criteria for Contaminated Soil
Excavated contaminated soil has to meet certain
criteria before disposal to landfill is allowed. The criteria are set out in
the Guidance Notes for Investigation and Remediation of Contaminated Sites of
Petrol Filling Stations, Boatyards and Car Repair/ Dismantling Workshops. These criteria relate primarily to Toxicity
Characteristic Leaching Procedure (TCLP) limits. In case these limits are exceeded,
in-situ treatments would be required before final disposal to landfill.
The potential environmental impacts associated with
the handling and disposal of waste during the construction and operational
phase will be assessed in accordance with the following:
·
Estimation of the
types, timing and quantities of the wastes to be generated; and
·
Assessment of the
potential impact on the capacity of waste collection, transfer and disposal
facilities.
Secondary environmental impacts due to the
management of waste, including potential air emission and noise arising from
the temporary spoil stockpiling and barging facility has been assessed and
evaluated in Sections 7 and 8 of this Report respectively.
During the construction phase, the main activities
(land based) that will potentially generate waste include excavation, tunnelling
(cut-&-cover, drill-&-blast, TBM, mining), demolition and construction
of stations and associated structures. Typical waste types associated with
these activities include:
·
C&D materials;
·
C&D waste;
·
Excavated
contaminated materials and marine sediments;
·
Chemical waste;
and
·
General refuse.
Bituminous materials generated will
be separated from other inert material during the onsite sorting process as far
as practicable.
The proposed alignment will run through various
layers of materials including rock at the bottom and marine sediments (as
residual material from previous reclamation works in Kai Tak and Ho Man Tin) at
some of the locations, and fill material on the top. These materials will need
to be excavated for cut-&-cover and open-cut activities (eg tunnels, stations etc). For bored and mined tunnelling, only the
spoil within the tunnel will be excavated. The construction of SCL (TAW-HUH) is
to be conducted in stages and the major construction sites are shown in Table 11.2.
Table 11.2 :
Key Working Sites during Construction of SCL (TAW-HUH)
|
Working Sites |
Activity Period |
|
|
From |
To |
|
|
HIK and TAW to Hin
Keng Viaducts & At Grade Structures |
2013 |
2016 |
|
Hin Keng to Ma Chai Hang Tunnels and MCV |
2013 |
2016 |
|
Ma Chai Hang to
DIH Tunnels and DIH to Prince
Edward Road East Tunnels |
2012 |
2016 |
|
Lung |
2012 |
2014 |
|
DIH & DHS |
2012 |
2016 |
|
DHS to KAT Tunnels and DIH (below |
2012 |
2015 |
|
KAT and Sections of Approach Tunnels |
2012 |
2015 |
|
TKW and Sections of Tunnels between KAT
& TKW and TKW to MTW Tunnels |
2012 |
2016 |
|
MTW and MTW to HOM Tunnels |
2012 |
2016 |
|
Kai Tak Runway Barging Facility |
2012 |
2012 |
|
HOM [1] |
2011 |
2015 |
|
HUH [1] |
2012 |
2015 |
Note:
[1] Construction of HOM and HUH will be implemented
under other Designated Project
Tables 11.3a-b give the
estimated quantity of C&D materials and sediments to be excavated.
Table 11.3a: Summary of quantities of C&D materials generated [1] [2]
|
C&D Material |
Total (m3) |
|
|
Soft Material |
|
3,489,600 |
|
Rock |
All grades |
452,200 |
|
Artificial Hard Material |
Bituminous /
Concrete pavement |
80,000 |
|
Sub-total |
|
4,021,800 |
|
Material Re-used |
|
455,000 |
|
Disposal |
|
3,566,800 |
Note:
[1] Quantities of C&D materials from HUH are: soil
material 138,000m3, and 52,600m3 sediment.
[2] Quantities of C&D materials from HOM are: rock
678,500m3, AHM 8,200m3, soil material 403,400m3 and
non-inert 5,900m3.
[3] The quantities shown above are estimates only and
will be subject to further review during the detailed design and construction
stage.
Table 11.3b: Summary of quantities of sediments generated
|
Material |
Total (m3) |
|
|
Sediments |
Land-based
& Marine-based sediment |
278,400 |
|
Sub-total |
|
278,400 |
Note:
The quantities shown above are estimates only
and will be subject to further review during the detailed design and
construction stage.
The total
volume of C&D materials and sediments generated is estimated to be
4,300,200m3. A total of 455,000m3 of the materials will
be reused in the project, whilst the remaining 3,845,200m3 is
required to be disposed. For HUH, 138,000m3 of soil and 52,600m3 of
sediment will be disposed of by SCL (MKK-HUH). For HOM, 678,500m3 of rock,
8,200m3 of AHM, 403,400m3 of soil and 5,900m3
of non-inert material will be disposed of by KTE.
The C&D
surplus materials are mainly generated from station construction in early stage
of the Project (Year 2012 ~ 2014). The fill materials are used for backfilling
on top of station and stabling sidings at later stage (Year 2015 ~ 2016).
Scheduling of construction programme to minimise spoil materials is therefore
not feasible. With the programme mismatch of excavation and backfilling, and
the lack of sufficient temporary stockpile area in urban city area, surplus
materials are required to be disposed of off-site. The construction programme,
however, will be reviewed during the detailed design stage to maximize the
quantity of on-site reused of surplus C&D material when there is opportunity
arisen.
Certain
amount of surplus materials will be used by other projects in
The combination of the urban setting
and the nature of the physical constraints have limited the availability of
alternative schemes for the station and tunnel construction (see Section 3). The current
design is to use embankment and viaduct at Tai Wai to Hin
Keng portal, drill and blast tunnelling below Lion
Rock and at Ho Man Tin; bored tunnelling along
Measures
have been adopted to minimise
the generation of C&D materials at the outset during the design stage. As excavation cannot be avoided, only
limited measures can be taken to minimise the quantity of C&D materials,
including:
·
Adoption
of tunnelling construction techniques (e.g. bored tunnelling along
·
Reduction
of the size and the number of offline plant rooms;
·
Minimisation
of the overall size of the plant buildings and tunnel box sections through
effective structural scheming for plant building and tunnel layout; and
·
Efficient
use of the space for station layout to minimise the overall width of the
station and tunnel box sections.
On-site
sorting of C&D material
All
C&D materials arising from the construction of SCL (TAW-HUH) will be sorted
on-site to recover the inert C&D materials and reusable and recyclable materials
prior to disposal off-site. All
inert C&D materials will be broken down according to the Dumping Licence
conditions before disposal to public filling outlets by barges.
The
Contractor will be responsible for devising a system to work for on-site sorting
of C&D materials and promptly remove all sorted and processed material
arising from the construction activities to minimise temporary stockpiling
on-site. It is recommended that the
system should include the identification of the source of generation, estimated
quantity, arrangement for on-site sorting and/ or collection, temporary storage
areas, and frequency of collection by recycling Contractors or frequency of
removal off-site.
It has
been assumed that inert C&D materials (e.g. soil, building debris,
concrete) will be sorted out from C&D materials at source to avoid double
handling. Silty/
clayey materials from alluvium and marine sediments will be identified at
source. Non-contaminated alluvial
and marine sediments will be transported by leak proof trucks to eliminate
water leakage during transportation to the barging facility for open sea
disposal. The trucks should also be
covered with impervious sheeting to prevent any dust emissions.
In order to identify materials which are not suitable to use as
aggregate in structural concrete (e.g. volcanic rock, Aplite
dyke rock, etc), geological assessment would be
carried out by competent persons on site during excavation. Volcanic rock and Aplite dyke rock will be separated at the source sites as
far as practicable and stored at designated stockpile areas preventing them
from delivering to crushing facilities. The crushing plant operator would also
be reminded to set up measures to prevent unsuitable rock from ended up at
concrete batching plants and be turned into concrete for structural use.
Details regarding control measures at source site and crushing facilities will
be submitted by the Contractors for the Engineer to review and agree. In
addition, site records will also be kept for the types of rock materials
excavated and the traceability of delivery will be ensured with the
implementation of Trip Ticket System and enforced by site supervisory staff as
stipulated under DEVB TC(W) No. 6/2010 for tracking of
the correct delivery to the rock crushing facilities for processing into
aggregates. Alternative disposal option for the reuse of volcanic rock and Aplite Dyke rock, etc will also be explored.
Due to the nature of the project, it
is not possible to achieve cut and fill balance for individual construction
contracts and the SCL (TAW-HUH) project.
With the limited space of project sites, it is also not practicable to
stockpile the excavated materials at individual worksites for subsequent
backfilling. Some of the excavated
materials have to be exported off-site.
A summary of the reused materials is given in Tables
11.4a-b below.
Table 11.4a: Summary of C&D material
generated, reused and disposed [1] [2]
|
C&D Materials |
Quantity of C&D Materials,
m3 |
|||
|
Generated |
Reused |
Disposed |
||
|
Soil Material |
|
3,489,600 |
455,000 |
3,034,600 |
|
Rock |
All grades |
452,200 |
- |
452,200 |
|
Artificial hard material (AHM) |
bituminous / concrete pavement |
80,000 |
- |
80,000 |
|
Subtotal |
4,021,800 |
455,000 |
3,566,800 |
|
Note:
[1] Quantities
of C&D materials from HUH are: soil material 138,000m3, and
52,600m3 sediment.
[2] Quantities
of C&D materials from HOM are: rock 678,500m3, AHM 8,200m3,
soil material 403,400m3. and non-inert
5,900m3.
[3] The
quantities shown above are estimates only and will be subject to further review
during the detailed design and construction stage.
Table 11.4b: Summary of sediments
generated, reused and disposed [1] [2]
|
Materials |
Quantity of C&D
Materials, m3 |
|||
|
Generated |
Reused |
Disposed |
||
|
Sediments |
Land-based and Marine-based Sediment |
278,400 |
- |
278,400 |
|
Subtotal |
278,400 |
- |
278,400 |
|
Note:
The quantities shown above are estimates
only and will be subject to further review during the detailed design and
construction stage.
The reused C&D materials would consist of fill Grade IV and V
decomposed granite materials. It is anticipated that the excavated Grade IV and
V decomposed granite materials consists of mainly Grade V, which is suitable
for backfilling. Concrete debris
will not be used as an on-site backfill material due to its relatively large
size, except for those less than 150mm in diameter which can be used as fill
when mixed with general fill materials.
It is also difficult to control the quality of compaction using concrete
debris as fill. The actual amount
of reused C&D material will depend on the content and quality of the
excavated materials.
Disposal Programme
for C&D Material
The estimated
disposal programme of surplus C&D material is shown below:
Table 11.5a: Summary of annual disposal quantities of C&D materials[1]
|
Waste
Type |
Annual
Disposal Quantities, m3 |
|||||
|
2012 |
2013 |
2014 |
2015 |
2016 |
||
|
|
150,750 |
1,293,600 |
1,630,130 |
373,760 |
41,300 |
|
|
Rock |
All grades |
18,120 |
75,060 |
150,700 |
202,600 |
5,700 |
|
Artificial Hard Material (AHM) |
Bituminous/ Concrete fragment |
52,180 |
22,780 |
5,000 |
- |
- |
|
Subtotal |
221,050 |
1,391,440 |
1,785,830 |
576,360 |
47,000 |
|
Note:
[1] Excluding the quantities of C&D materials at HOM and HUH (see Table 11.5c).
[2] The
quantities shown above are estimates only and will be subject to further review
during the detailed design and construction stage.
Table 11.5b: Summary of annual disposal quantities of sediments
|
Waste
Type |
Annual
Disposal Quantities, m3 |
|||||
|
2012 |
2013 |
2014 |
2015 |
2016 |
||
|
Sediments |
Land-based and Marine-based Sediment |
69,180 |
117,000 |
54,960 |
37,100 |
140 |
|
Subtotal |
69,180 |
117,000 |
54,960 |
37,100 |
140 |
|
Note:
The quantities shown above are estimates only and will be subject to
further review during the detailed design and construction stage.
Table 11.5c: Summary of annual disposal quantities of C&D materials at HUH and HOM [1]
|
Waste Type |
Annual Quantity Generated, m3 |
Total, m3 |
|||||
|
2011 |
2012 |
2013 |
2014 |
2015 |
2016 |
||
|
Hung Hom Station |
|||||||
|
0 |
16,000 |
81,000 |
41,000 |
0 |
0 |
138,000 |
|
|
Hom Man Tin Station |
|||||||
|
Rock |
18,300 |
612,800 |
47,400 |
0 |
0 |
0 |
678,500 |
|
AHM |
6,600 |
1,600 |
0 |
0 |
0 |
0 |
8,200 |
|
Soft Material |
296,200 |
105,800 |
1,400 |
0 |
0 |
0 |
403,400 |
|
Non-inert |
4,600 |
300 |
500 |
500 |
0 |
0 |
5,900 |
|
Subtotal |
325,700 |
736,500 |
130,300 |
41,500 |
0 |
0 |
1,234,000 |
Note:
[1] Construction
of HOM and HUH will be implemented under other Designated Project
[2] The
quantities shown above are estimates only and will be subject to further review
during the detailed design and construction stage.
The Project Proponent
shall notify CEDD of the estimated spoil volumes to be generated, and liaise
and agree with the Public Fill Committee for the disposal of surplus inert
C&D materials including good quality rock during the detailed design phase
of the project.
Surplus of rock and spoils materials
would be accepted by other projects, including Hong Kong Boundary Crossing
Facilities (HKBCF), Hong Kong Link Road (HKLR) and Tuen
Mun Chek Lap Kok Link (TMCLKL).
Discussions with relevant government departments and parties have been
made for disposal of surplus materials from railways projects including SCL
(TAW-HUH).
The
C&D materials include those from the construction of the stations,
cut-&-cover tunnels and bored tunnel. The spoil from the mucking out points
will be transported by dump trucks to the barging facilities for final
disposal. Barging points at Kai
Tak Runway and Freight Pier at Hung Hom (shared with
Kwun Tong Line Extension) have been proposed for SCL (TAW-HUH). The barging
facilities for SCL (TAW – HUH) would operate from 2012 to 2016, 12hours per
day. Locations of barging facilities are shown in Figure 11.1.
It is estimated that about 452,200m3
of Grade III or better rock will be produced and a 4ha of land for stockpile
dedicated facilities for stockpiling are recommended for SCL (TAW-HUH).
Locations of stockpile are shown in Figure 11.2.
About 80,000m3 of artificial hard materials (AHM) will be generated.
Broken asphalt will be recycled where practicable, whereas broken concrete will
be disposed of at the public fill.
These hard materials are proposed to be disposed of by trucks to the Tuen Mun Area 38 or Tseung Kwan O Area 137, as directed by CEDD or to local
recycling facilities.
11.4.1.2 C&D
Waste
C&D
waste will be generated throughout the construction works from general site
clearance works, tree felling, piling works and earthworks for construction of
various structures. These C&D non-inert materials will be disposed of at
NENT Landfill (see Appendix 11.2).
11.4.1.3 Imported
Fill Material
It is
estimated by the Engineer that an amount of 1,224,000m³ of fill materials will need to be imported. The imported fill materials are used for
backfilling on top of station and stabling sidings. With the programme mismatch
of excavation and backfilling and the lack of sufficient temporary stockpiling
area in urban city area, surplus materials will be disposed of off-site. And
some of the backfilling materials will have to be imported. The project
proponent shall review the programme during the detail design stage and
maximize the quantity of on-site reused of surplus C&D material.
11.4.1.4
Excavated
Contamination Materials and Marine Sediment
A Contamination Assessment Plan (CAP) has been
prepared to set out the requirements for a contamination evaluation of the SCL (TAW-HUH) and works areas. With the subsequent change of
design information, a revised CAP has been re-submitted in November 2010 and
endorsed by EPD on 10 December 2010.
Subsequently, the project boundary, at grade works sites and off site
works areas have been updated. A
supplementary CAP is prepared and submitted to EPD on 21 January 2011 to
reflect the latest changes of the project. The final endorsed CAP and
supplementary CAP to be approved by EPD is shown in Appendix 12.1 of Section 12. They collected
historical information and existing site conditions as the basis for land
contamination assessment. So far approximately 39m3 of soil is
confirmed to be contaminated at Site L4 (see Section 12). The detailed assessment findings are
reported in the Contamination Assessment Report (CAR), which has been endorsed
by EPD on 22 December 2009. “Excavation and Landfill Disposal” is considered as
the most suitable and cost effective remediation method for this relatively
small volume of contaminated soil. None of the contaminants exceed the TCLP
limits, so the remediation method of “Excavation and Landfill Disposal” is feasible.
Off-site disposal of treated contaminated should be considered as the
last resort/ option. A Remediation Action Plan (RAP) which includes
details of proposed remediation methods has been endorsed by EPD on 22 December
2009. A supplementary CAR has been
prepared to reflect the latest changes of the project. The endorsed CAR and RAP
and supplementary CAR are attached in Appendix 12.2 of
Section 12.
A summary of the generation of sediments is
given in Table 11.6.
Table
11.6: Summary
of annual generation of sediments [1]
|
Waste |
Annual
Disposal Quantities, m3 |
|||||
|
2012 |
2013 |
2014 |
2015 |
2016 |
Total |
|
|
Land based sediment and marine based sediment |
69,180 |
117,000 |
54,960 |
37,100 |
140 |
278,380 |
Note:
[1] Excluding
land based sediment from HUH amount 52,600m3.
[2] The
quantities shown above are estimates only and will be subject to further review
during the detailed design and construction stage.
A Sediment Sampling and Testing Plan (SSTP) has been submitted and
approved by EPD. Sediment Quality Report(s) will be prepared as per the
requirements given in the ETWBTC No 34/2002 ”Management of Dredged / Excavated
Sediment” and will be submitted to the DASO Team of EPD during the application
of dumping permit. SSTP of the project is shown in Appendix 11.3.
Based on
the available testing results, field sampling was collected during 2009 for
marine-based sediment at Kai Tak involving 19 drillholes,
and land-based sediment at Hung Hom and Kai Tak
involving 18 drillholes.
Land
Based Sediments
A total
of 34 samples had been collected and tested. Results indicate that 26 samples
registered in Category L (£ Lower Chemical Exceedance Level); 1 contained
Heavy Metal compounds registered in Categories M (Material > Lower & £ Upper Chemical Exceedance Level) and 7
samples were within Category H.
For the
samples classified as Category H, none of the contaminant levels tested
exceeding 10 times LCEL. Therefore, no samples classified as Category H
required biological screening tests. Only the sample classified as Category M
is required for biological screening tests.
The
chemical screening and biological screening tests revealed that 22 samples are
classified as Type 1 - Open Sea Disposal, 1 sample is classified as Type 1 -
Open Sea Disposal (Dedicated Sites) and 3 samples area classified as Type 2 -
Confined Marine Disposal. A summary of chemical screening results are presented
in Table 11.7.
Table 11.7: Summary of
Chemical Screening Results
|
Location |
Category |
No
of Samples |
Remarks |
|
Ho Man Tin |
L (£LCEL) |
3 |
|
|
Kai Tak |
L (£LCEL) |
19 |
|
|
M (> LCEL & £
UCEL) |
1 |
Exceedance
of LCEL in Hg |
|
|
H (> UCEL) |
3 |
Exceedance
of UCEL in heavy metals |
|
|
Hung Hom |
L (£LCEL) |
4 |
|
|
H (> UCEL) |
4 |
|
Quantity
estimation of marine sediment for excavation and sea disposal was given in the
Sediment Quality Report. The quantities
of sediment are estimated by multiplying the surface area requiring excavation
by the depth of sediment. The estimated quantities of sediment to be excavated
are summarized in Table 11.8.
Table 11.8:
Estimated quantity of different type of sediment
|
Disposal Options |
Category |
Estimated
Volume (x 1000 m3 ) |
|||
|
Ho Man Tin & Kai Tak |
Hung Hom |
Total |
% |
||
|
Type 1 |
Category
L |
181.1 |
33.4 |
214.5 |
78.0% |
|
Type 1 |
Category
M (pass biological screening test) |
14.7 |
0 |
14.7 |
5.4% |
|
Type 2 Confined
Marine Disposal |
Category
M (failed biological screening), Category
H |
26.5 |
19.2 |
45.7 |
16.6% |
|
Sub-total |
|
222.3 |
52.6 |
274.9 |
100% |
Marine
Based Sediments
A total
of 35 samples had been collected and tested. Results indicate that 1 sample was
within Category L. 1 sample contained Heavy Metal compounds registered in
Category M (Material
> Lower & £ Upper Chemical
Exceedance Level). 33 samples were within Category H (Material >
Upper Chemical Exceedance Level) and exceeding 10 times of Lower Chemical Exceedance Level
(LCEL). The chemical screening and biological screening tests revealed that 18
samples are classified as Type 2 – Confined Marine Disposal and 15 samples as
Type 3 – Special Treatment/ Disposal.
A summary of chemical and biological screening results are presented in Table 11.9.
Table 11.9: Summary of
Chemical and Biological Screening Results
|
Location |
Category |
No
of Samples |
Biological
Screening |
Remarks |
|
Kai
Tak Dredging Area |
L (£LCEL) |
1 |
N/A |
Type
1 – |
|
M (> LCEL & £
UCEL) |
1 |
Fail |
Type
2 – Confined Marine Disposal |
|
|
H (> UCEL) |
33 |
18 samples – Pass |
Type
2 – Confined Marine Disposal |
|
|
15 samples - Fail |
Type
3 – Special Treatment Disposal |
With
56,000 m3 marine based sediment, it is estimated that about 100m3 sediment requires Type 1 - Open Sea Disposal, 26,700m3
sediment requires Type 2 – Confined Marine Disposal Open Sea Disposal, and
29,200m3 requires Type 3 – Special Treatment/ Disposal. Detailed
testing results for chemical and biological tests and disposal classification
are presented in Appendix 11.4.
11.4.1.5 Chemical Waste
Chemical wastes likely to be generated from the
construction activities for the SCL (TAW- HUH) and associated facilities will
include:
·
Scrap
batteries or spent acid/alkali from their maintenance;
·
Used
paint, engine oils, hydraulic fluids and waste fuel;
·
Spent
mineral oils/cleansing fluids from mechanical machinery; and
·
Spent
solvents/solutions, some of which may be halogenated, from equipment cleansing
activities.
Chemical waste may pose serious
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 Packing, Labelling
and Storage of Chemical Waste. 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 amount of
chemical waste as it will be highly dependent on the Contractor’s on-site
maintenance practice and the quantities of plant and vehicles utilized.
However, it is anticipated that the quantity of chemical waste, such as
lubricating oil and solvent produced from plant maintenance will be small and
in the order of few hundred litres per month.
Chemical waste, irrespective of the likely
small amount, would pose serious environmental, health and safety hazards if
not properly managed. Such hazards
would include:
·
Toxic
effects to workers;
·
Adverse
effects on water quality from spills;
·
Fire
hazards; and
·
Disruption
of sewage treatment works should the chemical waste enter the sewerage
system.
The amount of chemical waste arising from
the construction activities would depend on the contractor’s on-site
maintenance practices and the amount of plant and number of vehicles
deployed. Relatively small quantity
of chemical waste, such as lubricating oil and solvent, produced from plant
maintenance would be anticipated, which would be collected by licensed
collectors for subsequent disposal at licensed waste disposal facilities, such
as the Chemical Waste Treatment Centre in Tsing
Yi. With the implementation of
proper preventive and mitigation measures for handling, transport and disposal,
no insurmountable environmental impacts would be anticipated.
11.4.1.6 General Refuse
The presence of a construction site with workers
and site office will result in the generation of a variety of general refuse
requiring disposal. General refuse will mainly consist of food waste, aluminium cans and waste paper.
The storage of general refuse has the
potential to give rise to adverse environmental impacts. These include odour if
the waste is not collected frequently (for example, daily), windblown litter,
water quality impacts if waste enters waster bodies, and visual impact. The
sites may also attract pests, vermin, and other disease vectors if the waste
storage areas are not well maintained and cleared regularly. In addition,
disposal of wastes at sites other than approved landfills, can also lead to
similar adverse impacts at those sites.
The number of work force (clerical and workers)
to be employed for the project is not available at this stage, but is
anticipated to be over 1,000 staff.
On this basis, the total refuse generated per day would be about
650kg/day, assuming the refuse generated rate is 0.65kg/head/day. Provided that the mitigation measures
are adopted, the potential environmental impacts caused by the storage,
handling, transport and disposal of general refuse are expected to be minimal.
It is recommended that general refuse should be collected on a daily basis for
disposal. Given the small quantity of general refuse, adverse impacts to the
operation of the landfills are not expected.
During the operational phase, the station and the
associated facilities will generate the following wastes:
·
General refuse;
·
Industrial waste;
and
·
Chemical waste.
11.4.2.1 General Refuse and Industrial Waste
General refuse will arise from the public, station
employees and commercial operators within the stations. Waste would include food, paper, wood,
plastic, office waste, metal containers etc. The storage and handling of these wastes
may give rise to environmental impacts.
Maintenance activities of the station and tracks
will generate industrial waste including scrap materials from rail and carriage
maintenance, used fluorescent tubes, used welding rods, cleansing materials and
discarded electronic equipment.
A reputable waste collector should be employed to
remove general refuse and industrial waste from the stations, separately from
chemical wastes, on a daily basis to minimise odour, pest and litter impacts.
Similar to industrial waste, lubricants, paints,
used batteries, mineral oil, coolants, and solvents will be generated during
the operational phase within the stations and alignment areas. These wastes may pose significant
environmental, health and safety hazard if they are not properly managed.
The requirements given in the Code of Practice on
the Packaging, Labelling and Storage of Chemical Wastes should be followed in
handling of these chemical wastes. A trip-ticket system should be operated
in accordance with the Waste Disposal (Chemical Waste) (General) Regulation to
monitor all movements of chemical wastes which will be collected by a licensed
collector to a licensed facility for final treatment and disposal.
The requirements as recommended in ETWB(W) No. 19/2005 Environmental Management on Construction
Sites and its latest version, and other relevant guidelines, should be included
in the Particular Specification for the Contractor as appropriate.
The Contractor should incorporate waste
management recommendations into a comprehensive on-site Environmental
Management Plan (EMP) based on the Construction and Demolition Material
Management Plan (C&DMMP). The EMP shall be
submitted to the Engineer for approval after commencement of construction. This
should include all factors dependent on individual work sites including
designation of areas for the segregation and temporary storage of materials for
future use or recycling. Such provision cannot be specified at this stage.
Contractors should follow the recommendations of ETWBTC (Works) No. 19/2005 for
on-site separation of waste, and DEVBTC (Works) No. 6/2010 for trip-ticket
system for disposal of construction and demolition material. The EMP shall also
define clearly the hierarchy for waste management on and off-site as well as a
complete list of mitigation measures for handling excavated materials.
Waste management options with less
environmental impacts are preferred.
The waste management hierarchy should be as follows:
·
Avoidance
and minimization;
·
Reuse
of materials;
·
Recovery
and recycling; and
·
Treatment
and disposal.
This hierarchy should be used to evaluate
the waste management options to allow maximum waste reduction and often
reducing costs. For example, by reducing or eliminating over-ordering of
construction materials, waste is avoided and costs are reduced both in terms of
purchasing raw materials and disposing of wastes. Records of quantities of
wastes generated, recycled and disposal (locations) should be properly kept.
A trip-ticket system should be established
and will comply with the Waste Disposal (Charges for Disposal of Construction
Waste) Regulation to monitor the disposal of public fill and solid wastes at
public filling facilities and landfills, and to control fly-tipping. A trip-ticket system will be included as
one of the contractual requirements and implemented by the Contractor. The
Engineer shall audit the result of the system.
A recording system for the amount of waste
generated, recycled and disposed of (including the disposal sites) should be
established during the construction phase.
The Contractor should provide training to workers on the concepts of
site cleanliness and on appropriate waste management procedures, including
waste reduction, reuse and recycling at the beginning of the Contract.
The Project Proponent shall notify CEDD of
the estimated spoil volumes to be generated, and liaise and agree with the Public
Fill Committee (PFC) for the disposal of any surplusinert
C&D materials including good quality rock during detailed design of the
project. A C&DMMP had been submitted to and subsequently endorsed by PFC on
12 August 2011. The PFC endorsement letter was attached in Appendix 11.5.
The Project Proponent will ensure all the mitigation measures mentioned in the
C&DMMP and conditions stated in the endorsement memo will be complied with.
Wherever practicable, C&D materials should be segregated from other wastes
to avoid contamination and ensure acceptability at public filling areas or
reclamation sites. The surplus C&D material would be reused within the site
as much as possible. The project proponent shall
obtain confirmation from PFC on the proposed disposal arrangement before the
commencement of the construction works. No construction work is allowed to
proceed until all issues on management of C&D materials have been resolved
and all relevant arrangements have been endorsed by the relevant authorities
including PFC and EPD.
The following mitigation measures should be
implemented in handling the C&D materials:
·
Maintain
temporary stockpiles and reuse excavated fill material for backfilling and
reinstatement;
·
Carry
out on-site sorting;
·
Make
provisions in the Contract documents to allow and promote the use of recycled
aggregates where appropriate;
·
Adopt
‘Selective Demolition’ technique to demolish the existing structures and
facilities with a view to recovering broken concrete effectively for recycling
purpose, where possible;
·
Implement
a trip-ticket system for each works contract to ensure that the disposal of
C&D materials are properly documented and verified; and
·
Implement
an enhanced Waste Management Plan, which become a part of the Environmental
Management Plan in accordance with “ETWBTC (Works) No. 19/2005 – Waste
Management on Construction Site”, to encourage on-site sorting of C&D
materials and to minimize their generation during the course of construction.
·
In
addition, disposal of the C&D materials onto any sensitive locations such
as agricultural lands, etc. should be avoided. The Contractor shall propose the final
disposal sites to the Project Proponent and EPD to get their approval before
implementation.
11.5.1.2 C&D
Waste
The
following mitigation measures should be implemented in handling of C&D
waste:
·
Standard
formwork or pre-fabrication should be used as far as practicable in order to minimise the arising of C&D materials. The use of more durable formwork or
plastic facing for the construction works should be considered. Use of wooden hoardings should not be
used, as in other projects. Metal
hoarding should be used to enhance the possibility of recycling. The purchasing of construction materials
will be carefully planned in order to avoid over ordering and wastage.
·
The
Contractor should recycle as much of the C&D materials as possible
on-site. Public fill and C&D
waste should be segregated and stored in different containers or skips to
enhance reuse or recycling of materials and their proper disposal. Where practicable, concrete and masonry
can be crushed and used as fill. Steel
reinforcement bar can be used by scrap steel mills. Different areas of the
sites should be considered for such segregation and storage.
·
HKSAR
has developed and implemented a charging policy for the disposal of waste to
landfill. It will provide additional incentive to reduce the volume of waste
generated and to ensure proper segregation to allow disposal of inert material
to public filling areas.
11.5.1.3 General Refuse
General refuse generated on-site should be
stored in enclosed bins or compaction units separately from construction and
chemical wastes. A reputable waste collector should be employed by the
Contractor to remove general refuse from the site, separately from construction
and chemical wastes, on a daily basis to minimize odour, pest and litter
impacts. Burning of refuse on
construction sites is prohibited by law.
Aluminium cans are often recovered from the waste
stream by individual collectors if they are segregated and made easily
accessible. Separate labelled bins for their deposit should be provided if
feasible.
Office wastes can be reduced through the
recycling of paper if volumes are large enough to warrant collection.
Participation in a local collection scheme should be considered by the
Contractor. In addition, waste separation facilities for paper, aluminium cans, plastic bottles etc., should be provided.
11.5.1.4 Excavated Contaminated Materials and Land-based and
Marine-based Marine Sediment
Contaminated Soil
About 39 m3 of
contaminated soil is identified (refer to Section 12 for details). Given the small amount of volume,
disposal in landfill site is recommended.
Potential landfill site includes NENT. Details of the mitigation measures on
handling of the contaminated soil shall be referred to Section 12.11.
Land-based and Marine-based Sediment
The total amount of land-based and
marine-based sediments is estimated to be 278,500m3. Normally, the contaminated sediment will
require to be disposed of at confined contaminated mud pits such as East Sha Chau, while the
uncontaminated marine and alluvial deposit will require open sea disposal, e.g.
in South Cheung Chau, Nine Pin, etc. However, no dredging work is allowed to
proceed until all issues on management of dredged sediments have been resolved
and all relevant arrangements have been endorsed by the relevant authorities
including MFC and EPD.
Possible mitigation measures to handle the
contaminated/ uncontaminated sediment are summarized as follows:
·
All construction
plant and equipment shall be designed and maintained to minimise the risk of
silt, sediments, contaminants or other pollutants being released into the water
column or deposited in the locations other than designated location.
·
All vessels shall
be sized such that adequate draft is maintained between vessels and the sea bed
at all states of the tide to ensure that undue turbidity is not generated by
turbulence from vessel movement or propeller wash.
·
Before moving the
vessels which are used for transporting dredged material, excess material shall
be cleaned from the decks and exposed fittings of vessels and the excess
materials shall never be dumped into the sea except at the approved locations.
·
Adequate freeboard
shall be maintained on barges to ensure that decks are not washed by wave
action.
·
The Contractors
shall monitor all vessels transporting material to ensure that no dumping
outside the approved location takes place.
The Contractor shall keep and produce logs and other records to
demonstrate compliance and that journeys are consistent with designated
locations and copies of such records shall be submitted to the Engineers.
·
The Contractors
shall comply with the conditions in the dumping licence.
·
All bottom dumping
vessels (hopper barges) shall be fitted with tight fittings seals to their
bottom openings to prevent leakage of material.
·
The material shall
be placed into the disposal pit by bottom dumping.
·
Contaminated
marine mud shall be transported by split barge of not less than 750m3
capacity and capable of rapid opening and discharge at the disposal site.
·
Discharge shall be
undertaken rapidly and the hoppers shall be closed immediately. Material adhering to the sides of the
hopper shall not be washed out of the hopper and the hopper shall remain closed
until the barge returns to the disposal site.
·
For Type 3 special
disposal treatment, sealing of contaminant with geosynthetic
containment before dropping into designated mud pit would be a possible
arrangement. A geosynthetic containment method is a
method whereby the sediments are sealed in geosynthetic
containers and, the containers would be dropped into the designated
contaminated mud pit where they would be covered by further mud disposal and
later by the mud pit capping at the disposal site, thereby fulfilling the
requirements for fully confined mud disposal. The technology is readily
available for the manufacture of the geosynthetic
containers to the project-specific requirements. Similar disposal methods have
been used for projects in Europe, the
·
Moreover, the geosynthetic
containment has also been proposed for Type 3 disposal in the EIA Study under Wan
Chai Development Phase II and Central-Wan Chai Bypass (WDII) (EIA 141/2007). Several field trials had been undertaken under
WDII - Design and Construction to demonstrate the feasibility on the use of the
geosynthetic containment. Report on the field trials
concluded that disposal by sealing sediments in geosynthetic
containers and dropping these containers into the contaminated mud pits at East
Sha Chau has been shown to
be a successful and viable disposal method. The use of a geosynthetic containment for special disposal was
considered to be an effective system with negligible loss of contaminants to
the marine environment during disposal.
11.5.1.5 Chemical Waste
Chemical waste producers should be
registered with EPD. For those processes which generate chemical waste, the
Contractor shall identify any alternatives that generate reduced quantities or
even no chemical waste, or less dangerous types of chemical waste.
Chemical waste should be handled in
accordance with the Code of Practice on the Packaging, Handling and Storage of
Chemical Wastes as follows. Containers used for storage of chemical wastes
should:
·
Be
suitable for the substance they are holding, resistant to corrosion, maintained
in a good condition, and securely closed;
·
Have a
capacity of less than 450 L unless the specification have been approved by 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 should:
·
Be
clearly labelled and used solely for the storage of
chemical wastes;
·
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 the area, whichever is greatest;
·
Have
adequate ventilation;
·
Be
covered to prevent rainfall entering (water collected within the bund must be
tested and disposed as chemical waste, if necessary); and
·
Be
arranged so that incompatible materials are adequately separated.
Disposal
of chemical waste should:
·
Be via
a licensed waste collector; and
·
Be 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 storage
containers; or
·
Be to a
re-user of the waste, under approval from EPD.
11.5.2.1 General Refuse and Industrial Waste
A reputable waste collector should be employed to
remove general refuse and industrial wastes from the stations on a daily basis
to minimise odour, pest and litter impacts.
11.5.2.2 Chemical Waste
The requirements
given in the Code of Practice on the
Packaging, Labelling and Storage of Chemical Wastes
should be followed, where applicable, in handling of these chemical
wastes. A trip-ticket system should
be operated in accordance with the Waste
Disposal (Chemical Waste) (General) Regulation to monitor all movements of
chemical wastes which would be collected by a licensed collector to a licensed
facility for final treatment and disposal.
The details of mitigation measures are as described in Section 11.5.1.7.
With the
implementation of recommended mitigation measures, adverse residual impacts are
not anticipated for both the construction and operational phases.
The quantity and timing for the generation
of waste during the construction phase have been estimated. Measures, including the opportunity for
on-site sorting, reusing excavated fill materials (stored in stockpiles) etc,
are devised in the construction methodology to minimise the surplus materials
to be disposed off-site via the designated barging facilities. The annual disposal quantities for
C&D materials and their disposal methods have also been assessed.
Recommendations have been made for
the Contractor for implementation during the construction period to minimise
the waste generation and any off-site disposal.
The types and quantities of waste that would be generated during the
operational phase have been assessed.
Recommendations have been made to ensure proper treatment and disposal
of these wastes.