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Contents |
Chapter Title Page
This section identifies the potential waste
arising from the construction and operation activities of the Project and
evaluates the potential environmental impacts that may result from waste
generated. Mitigation measures and good
site practices, including waste handling, storage and disposal, are recommended
with reference to applicable waste legislation and management guidelines to
minimise potential waste management impacts.
7.2 Waste Management Legislations, Standards and Guidelines
The
following legislation relates to the handling, treatment and disposal of wastes
in
¡ Waste Disposal Ordinance (Cap. 354)
¡ Waste Disposal (Chemical Waste) (General) Regulation (Cap. 354C)
¡ Waste Disposal (Charges for Disposal of Construction Waste) Regulation (Cap. 354N)
¡ Public Health and Municipal Services Ordinance (Cap. 132) - Public Cleansing and Prevention of Nuisances Regulation
¡ Land (Miscellaneous Provisions) Ordinance (Cap. 28)
¡ Dumping at Sea Ordinance (Cap. 466)
The Waste Disposal Ordinance (WDO) prohibits the unauthorised disposal of wastes. Construction waste is defined as any substance, matter or thing that is generated from construction work and abandoned, whether or not it has been processed or stockpiled before being abandoned, but does not include any sludge, screenings or matter removed in or generated from any desludging, desilting or dredging works. Under the WDO, wastes can be disposed of only at designated waste disposal facilities.
Under the WDO, the Chemical Waste (General) Regulation provides regulations for chemical waste control, and administers the possession, storage, collection, transport and disposal of chemical wastes. The Environmental Protection Department (EPD) has also issued a ‘guideline’ document, the Code of Practice on the Packaging, Labelling and Storage of Chemical Wastes (1992), which details how the Contractor should comply with the regulations on chemical wastes.
The Public Cleansing and Prevention of Nuisances Regulation provides control on illegal tipping of wastes on unauthorised (unlicensed) sites.
7.2.2 Inert Construction and Demolition (C&D) Materials
The current policy related to the dumping of inert C&D materials is documented in the Works Branch Technical Circular No. 2/93, ‘Public Dumps’. Construction and demolition materials that are wholly inert, namely public fill, should not be disposed of to landfill, but taken to public filling areas, which usually form part of reclamation schemes. The Land (Miscellaneous Provisions) Ordinance requires that dumping licences be obtained by individuals or companies who deliver public fill to public filling areas. The Civil Engineering & Development Department (CEDD) issues the licences under delegated powers from the Director of Lands.
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 for disposal must consist entirely of inert material.
7.2.3 Excavated Sediment
Practice Notes for Authorized Persons, Registered Structural Engineers and Registered Geotechnical Engineers, PNAP No. ADV-21 (Previous Reference: PNAP No. 252) Management Framework for Disposal of Dredged / Excavated Sediment sets out the procedures for seeking approval to dredge/excavate sediment and the management framework for marine disposal of such sediment. Excavated sediment arising from the Project, if any, will be managed in accordance with the requirements of PNAP ADV-21.
In accordance with the Dumping at Sea
Ordinance (DASO), application for dumping
permits from EPD is required for marine disposal of dredged/excavated
sediment, if any.
The
criteria for assessing waste management implications are outlined in Annex 7 of
the
¡ Identify the quantity, quality and timing of waste arising as a result of the construction and operation activities of the Project.
¡
Assessment of potential impacts from the management
of solid waste with respect to potential hazards, air and odour
emissions, noise, wastewater discharges and public transport.
¡
Assessment of impacts on the capacity of waste
collection, transfer and disposal facilities.
7.4 Identification, Prediction and Evaluation of Environmental Impact
The activities to be carried out for construction of the WKCD would generate a variety of wastes that can be divided into different key categories based on their composition and ultimate method of disposal. The identified waste types include:
¡ Inert Construction and demolition (C&D) materials;
¡ C&D materials from site clearance;
¡ Chemical waste; and
¡ General refuse.
Each type of the above waste arising is described below, together with an evaluation of the potential environmental impacts associated with the waste generation, handling, storage, transport and disposal. It should be noted that no marine sediments would be excavated from the WKCD site (see Section 7.4.1.1).
7.4.1.1 Inert Construction and Demolition (C&D) Materials
Key sources of inert C&D materials
The excavation works for WKCD basement (including
the underpass road and the flyover) will be the major source of inert C&D
materials (mainly soil) generated by the Project. It is estimated that the
total amount of inert C&D materials to be generated would be approximately 1,910,200
m3, in which about 1,837,200 m3 would be generated from
excavation work for the WKCD basement and the remaining 73,000 m3
would be from construction of superstructures and substructures. The bulk excavation
for the basement will be proceeded on a zone-by-zone
basis from 2013 to 2017, and the
construction of superstructures and substructures would be carried out
progressively from 2013 to 2020. Based on the tentative construction programme
(see Appendix
2.4), the amounts of inert C&D materials to be generated in
different years have been estimated as summarized in Table 7.1.
Table 7.1: Estimates of Inert C&D materials to be Generated by WKCD Project
|
Year |
Estimated
Amount of Inert C&D materials from WKCD Basement Excavation (m3) |
Estimated
Amount of Inert C&D materials from Construction of
Superstructures and Substructures (m3) |
Estimated
Total (m3) |
|
2013 |
17,000 |
7,270 |
24,270 |
|
2014 |
521,800 |
9,400 |
531,200 |
|
2015 |
639,400 |
9,600 |
649,000 |
|
2016 |
405,500 |
9,720 |
415,220 |
|
2017 |
253,500 |
9,640 |
263,140 |
|
2018 |
-- |
9,660 |
9,660 |
|
2019 |
-- |
9,660 |
9,660 |
|
2020 |
-- |
8,050 |
8,050 |
|
Total |
1,837,200 |
73,000 |
1,910,200 |
The quantity of inert C&D materials to
be generated from construction of superstructures and substructures has been estimated
by applying the generation rate of 0.1m3 per m2 of gross
floor area (GFA), which is based on the Reduction of Construction Waste Final
Report published by the
On-site
reuse / import of inert C&D materials as fill materials
The WKCD development will require fill
material for construction of the Park and the materials are proposed to be
obtained from reuse of the inert C&D materials generated by the Project as
far as practicable. Nevertheless, it is
anticipated that newly imported material will be required, though all practicable
measures will be employed for reuse of the inert C&D materials generated by
the Project before consideration of importing material.
It is estimated that the WKCD Project would require a total of 557,600 m3 of fill materials for construction of the Park. While all practicable measures will be employed for reuse of the inert C&D materials generated by the WKCD Project before consideration of importing material, it is anticipated that about 156,400 m3 of the inert C&D materials generated by the WKCD Project would be reused as the fill material mainly for construction of the Park. Therefore, about 401,200 m3 (557,600 – 156,400 m3) of fill material will need to be imported to this Project, as detailed in Table 7.2, whereas about 1,753,800 m3 (1,910,200 – 156,400 m3) of inert C&D materials will require off-site reuse by other projects or disposal during the period from 2013 to 2020. The overall proportion of inert C&D materials to be reused on-site from 2013 to 2020 appears to be relatively low (about 28% of the total amount of fill materials required) chiefly because of the space constraints for stockpiling within the WKCD site, and hence the inert C&D materials generated by the Project would be required to be immediately transported to other available projects for off-site reuse wherever practicable. Nevertheless, subject to the future contractor’s detailed construction programme the amount of inert C&D materials that can actually be reused on-site may be higher than the current estimates.
Table 7.2: Estimates of Fill Materials to be Imported from Other Potential Projects and/or Government’s Fill Banks
|
Year |
Estimated Fill
Material required at WKCD (m3) |
Estimated Inert
C&D Materials to be reused on-site as Fill Material (m3) |
Estimated Fill Materials to be imported from Other
Potential Projects and/or Government’s Public Fill Reception Facilities (m3) |
|
2013 |
54,200 |
8,270 |
45,930 |
|
2014 |
127,230 |
42,400 |
84,830 |
|
2015 |
108,200 |
37,500 |
70,700 |
|
2016 |
96,530 |
32,230 |
64,300 |
|
2017 |
105,720 |
26,340 |
79,380 |
|
2018 |
65,720 |
9,660 |
56,060 |
|
2019 |
0 |
0 |
0 |
|
2020 |
0 |
0 |
0 |
|
Total (round up figure) |
557,600 |
156,400 |
401,200 |
Off-site reuse of surplus inert C&D
materials
There will be a number of large
infrastructures projects under construction phase during the period from 2013
to 2017, which are identified as potential users of the excavated inert C&D
materials from the WKCD Project. The
proponents of such projects have been approached to identify the possibility of
using the inert C&D materials from this Project. Based on the feedback from the project
proponents, two potential projects have been identified, namely, the Hong
Kong-Zhuhai-Macao Bridge (HZMB) and the 3rd runway project (copies of
relevant correspondences attached
in Appendix
7.5).
As discussed in the meeting with the consultant
of HZMB project on 31 July 2012, it is possible for the HZMB project to use the
surplus inert C&D materials from this WKCD Project. Based on the fill
demand provided from the contractor of HZMB project, the surplus inert C&D
materials could be delivered to HZMB during the period from December 2013 - August
2014. Communication mechanism has been established with the HZMB project consultant,
and regular meetings will be conducted with the HZMB project consultant and contractor
for further liaison of logistics arrangement.
Based on the project profile entitled “Expansion
of Hong Kong International Airport into a Three-Runway System” (i.e., 3rd
runway project) available from the EPD’s website, major construction works of
the project, which will involve land formation of about 650 ha, would be
expected to commence in mid 2015 and completion of the project would be
expected by end 2022. Verbal response
from the project proponent indicated that provided construction of the 3rd
runway project could be commenced as expected in the project profile, it would
be possible for the project to receive the inert C&D materials generated
from this WKCD Project. According to the
information presented in the project profile, it would be reasonable to
anticipate that the 3rd runway project could receive fill materials
for its land formation work from the WKCD Project in 2016 and 2017. Liaison with the project proponent regarding
the arrangement of using the inert C&D materials from WKCD Project will be
made at a later stage when the programme of the 3rd runway project has become
clearer.
In view of the responses received and the
available information, it can be estimated that the total amount of inert
C&D materials to be used by the HZMB project and/or the 3rd runway project
in 2013, 2014, 2016 and 2017 would be about 905,000 m3, as detailed
in Table 7.3
below. In 2015, however, none of the inert
C&D materials generated could be used by either of the two projects. The
actual quantities and arrangement for using the inert C&D materials from
WKCD Project will be subject to the programmes of the two projects and liaison
with the relevant parties.
Table 7.3: Estimates of Inert C&D
materials to be Used by Other Potential Projects
|
Year |
Potential user projects of inert C&D materials |
Estimated quantity of inert C&D materials that would be used by
the projects (m3) |
Assumptions |
|
2013 |
HZMB |
16,000 |
90% of the
amount of inert C&D materials to be generated in December 2013 (17,800 m3)
would be used by the potential project |
|
2014 |
HZMB |
278,500 |
90% of the
amount of inert C&D materials to be generated from January to August 2014
(309,400 m3) would be used by the potential project |
|
2015 |
None |
0 |
Not applicable |
|
2016 |
3rd runway
project |
373,700 |
90% of the
amount of inert C&D materials to be generated in 2016 (415,220 m3)
would be used by the potential project |
|
2017 |
3rd runway
project |
236,800 |
90% of the
amount of inert C&D materials to be generated in 2017 (263,140 m3)
would be used by the potential project |
|
2018 – 2020 |
None |
0 |
Not applicable |
|
|
Total |
905,000 |
|
During the detailed design stage, further alternative disposal arrangement (e.g.,
other potential projects that could receive inert C&D materials from the WKCD Project) shall be continuously explored
and identified. If no potential projects could receive the surplus inert
C&D materials, the remaining inert C&D materials could be disposed of at
the Government's Public Fill Reception Facilities (PFRFs) for beneficial use by
any other projects in
Off-site disposal of inert C&D materials
From the above
estimates, the amount of inert C&D materials produced from the WKCD Project
that would neither be reused on-site nor be reused by the two potential projects
would be about 848,800 m3 (1,910,200 – 156,400 – 905,000 m3),
which will need to be disposed of at the Government’s Public Fill Reception
Facilities (PFRFs) for beneficial use by other projects in Hong Kong. Hence, the forecast quantities for yearly generation,
on-site reuse, off-site reuse and disposal of inert C&D materials at PFRFs are as summarised in Table 7.4 below.
Table 7.4: Estimates of Inert C&D
materials to be Generated, Reused On-site, Reused Off-site and Disposed
|
Year |
Amount of inert C&D materials (m3) |
|||
|
|
Generation |
On-site Reuse |
Off-site Reuse |
Disposed of at PFRF |
|
2013 |
24,270 |
8,270 |
16,000 |
0 |
|
2014 |
531,200 |
42,400 |
278,500 |
210,300 |
|
2015 |
649,000 |
37,500 |
0 |
611,500 |
|
2016 |
415,220 |
32,230 |
373,700 |
9,290 |
|
2017 |
263,140 |
26,340 |
236,800 |
0 |
|
2018 |
9,660 |
9,660 |
0 |
0 |
|
2019 |
9,660 |
0 |
0 |
9,660 |
|
2020 |
8,050 |
0 |
0 |
8,050 |
|
Total |
1,910,200 |
156,400 |
905,000 |
848,800 |
Liaison with the
CEDD Public Fill Committee (PFC) on the allocation of space for disposal of the
inert C&D materials at PFRFs is underway.
No construction work is allowed to proceed until all issues on
management of inert C&D materials have been resolved and all relevant
arrangements have been endorsed by the relevant authorities including PFC and
EPD.
It is proposed that four temporary barging
points at the south of the site will
be handed over from the XRL project to WKCD for handling the inert C&D materials of this Project. Dump trucks
will be used for removal of inert
C&D materials generated from construction site to the
barging points. The estimated maximum total handling volume
of inert C&D materials at the four barging points will be 4,000 m3/day. However, it is noted that these barging
points have limited handling capacity and their availability, or lack of it,
may affect the arrangement and programming of disposal of public fill by barge.
A booking system is in place to facilitate such disposal and this must be
followed by prospective users. The indicative locations of the barging points
are as shown in Figure
3.4a.
Both land and marine access to the
PFRFs are subject to
capacity limitations, and hence quota and booking systems may be applied in
order to ensure the disposal is carried out in controlled manner. The storage, handling, transport and disposal of surplus inert C&D materials,
if not managed properly, would have the potential to create visual, water
quality and dust impacts. Therefore, the
waste reduction measures and good site practices as detailed in Section 7.5.1 will be implemented to
minimize the amount of surplus inert C&D materials as well as to prevent or
reduce the associated potential impacts.
Review of any excavated marine sediments
Excavation depths at different zones are
proposed to accommodate the underground vehicular traffic and various
facilities including parking, loading & unloading areas and electrical &
mechanical (E&M) plant and locations of the zones are provided in Appendix 7.1. The anticipated excavation levels for
bulk excavation of the basement at different zones are indicated as follows:
Zone 1 :
-2.1mPD
Zones 2a and 2b : -6.5mPD
Zone 3 :
-1.1mPD
Zone 4 :
-16.95mPD
The WKCD site is a piece of reclaimed land. Based on the previous reports available from
the Geotechnical Engineering Office and relevant approved
Zone 1
According
to the GI completed for the WKCD site at Zone 1 in March 2013, covering a total
of 5 drillholes (A1-A, A2-B, A3-B, A4-A and A5-B), no
marine sediment was encountered in drillholes A2-B,
A3-B, A4-A and A5-B whereas a thin layer of marine sediment was found locally
in drillhole A1-A between the depths of -12.68mPD and
-14.73mPD. Details of the drillhole locations and records are given in Appendix 7.1. Based on the relevant drillhole record no. KSD100/DHE056 from the
Given
that the 5 drillhole records (A1-A, A2-B, A3-B, A4-A
and A5-B) show no marine sediments down to -12.68mPD; the presence of marine
sediment at drillhole KSD100/DHE056 (between -2.29 mPD and -7.29 mPD) was not
ascertained; and the proposed excavation level at this Zone is only down to about
-2.1 mPD, it is considered that marine deposit
would not be excavated at Zone 1.
Zone 2a
The
site in Zone 2a was reclaimed in early 2000.
This Zone is currently the construction site for the Hong Kong Section
of XRL project and the proposed ventilation facilities in West Kowloon Terminus
(WKT) were proposed to be built underneath this Zone with approximately -22mPD
by excavation (see Appendix 7.2).
Sediment was
found at certain sections of the proposed WKT with reference to the geological
profile information. It is noted in the
XRL
Zone
2b
The site in this Zone was reclaimed in 1990s. Ground investigation works were carried out at Zone 2b under the project for MTRC Kowloon Station Package 5, 6 and 7 for water cooling system in 2001. The relevant drillhole records (drillhole nos. BH4 and BH5 as shown in Appendix 7.3) showed that only fill material was present while marine deposit was not present at the proposed excavation depth for this Zone, i.e -6.5mPD.
In addition, based on the project for West Kowloon Reclamation Southern Area Roads Roads D10, D12 and D13 in 1994, the relevant drillhole records (drillhole nos. 62 - 68 as shown in Appendix 7.3) showed that only fill material was present while marine deposit was not present at the proposed excavation depth to this Zone, i.e. -6.5mPD. From the above quoted results, it is considered that marine deposit would not be excavated at Zone 2b.
Zone
3
The site in this Zone was reclaimed in 1990s. Ground investigation works were carried out at Zone 3 under the project for West Kowloon Reclamation Southern Area Roads D10, D12 and D13 in 1994. The relevant drillhole records (drillhole nos. 73, 73A, 74 and 75 as shown in Appendix 7.4) showed that only fill material was present while marine deposit was not present at the proposed excavation depth for this Zone, i.e -1.1mPD. From the above quoted results, it is considered that marine deposit would not be excavated at Zone 3.
Zone
4
The site in this Zone was reclaimed in 1990s. Ground investigation work was not undertaken after reclamation in this zone. However, referring to the nearest locations of drillhole records under West Kowloon Reclamation Southern Area Roads (Roads D10, D12 and D13) in 1994, the relevant drillhole records (drillhole nos. 76-81 as shown in Appendix 7.4) showed that only fill material was present while marine deposit was not present at the proposed excavation depth for this Zone, i.e -16.95mPD. These drillholes are considered representative of the site by virtue of its close proximity and same stage of reclamation (in 1990s) .From the above quoted results, it is considered that marine deposit would not be excavated at Zone 4.
7.4.1.2 C&D Materials from Site Clearance Works
During the general site clearance in
preparation for the subsequent construction works, it is estimated that the top
0.3m soil layer of the entire site excluding the XRL works area temporarily
occupying the site (with a net area of around 40 – 3.9 = 36.1 ha) would be
removed, and hence approximately 108,300m3 of C&D materials would
be generated. The XRL works area is
excluded from the estimation because it is reasonable to assume that the XRL
works area will have been cleared when it is returned to the Project
Proponent. These C&D materials would
mainly be a mixture of topsoil and vegetative material, and are considered as not suitable for
direct reuse by any earthworks on site due to its non-inert contents. However, the inert materials should be
segregated from the C&D materials on site for reuse as far as practicable,
subject to constraints of the site area.
The segregated inert materials that cannot be reused on site will be disposed of at the
Government’s PFRFs for beneficial use by other projects in
7.4.1.3 Chemical Waste
Chemical wastes arising during the construction phase may pose environmental, health and safety hazards if not stored and disposed of in an appropriate manner as stipulated in the Waste Disposal (Chemical Waste) (General) Regulations. The potential hazards include:
¡ Toxic effects to workers;
¡ Adverse impacts on water quality from spills and associated adverse impacts on marine biota; and
¡ Fire hazards.
The maintenance and servicing of construction plant and equipment may generate some chemical wastes such as used solvents, contaminated rags and waste lubricating oil. It is difficult to quantify the amount of chemical waste that will arise from the construction activities since it will be dependent on the Contractor’s on-site maintenance requirements and the amount of plant utilised. However, it is anticipated that the quantity of chemical waste, such as waste lubricating oil and solvents produced from plant maintenance, will be small and in the order of a few cubic metres per month. The amount of chemical waste to be generated will be quantified in the Waste Management Plan to be prepared by the Contractor for the site.
Materials
classified as chemical wastes will
require special handling and storage arrangements before removal for off-site disposal
at the approved Chemical Waste Treatment Facility or recycling by licensed
facilities. Mitigation and control requirements for chemical wastes are
detailed in Section 7.5.1.4. Provided that the handling, storage and
disposal of chemical wastes are in accordance with these requirements, adverse
environmental impacts are not expected.
7.4.1.4 General Refuse
The construction workforce will generate refuse comprising
food scraps, waste paper and
empty containers etc. Such refuse will
be properly managed so that intentional or accidental release to the
surrounding environment will be avoided. Disposal of refuse at sites other than
approved waste transfer or disposal facilities will be prohibited.
Effective collection of site wastes will be required to prevent waste
materials being blown around by wind, flushed or leached into the marine
environment, or creating an odour nuisance or pest/vermin problem. Waste
storage areas will be well
maintained and cleaned regularly. The
daily arising of general refuse from the construction workforce can be estimated based on a generation rate of 0.65 kg
per worker per day.
The maximum number of construction workers to be employed for each year from 2013 is stated in Table 7.5. Based on a generation rate of 0.65 kg per worker per day, the maximum daily arising of general refuse during the construction period would be approximately 975 kg and this waste can be effectively controlled by normal measures.
Table 7.5: Estimation of Maximum Number of Construction Workers during Construction Phase
|
Construction Year |
Maximum Number of Construction Workers |
Maximum Daily Arising of General Refuse (kg/day) |
|
2013 |
600 |
390 |
|
2014 |
1000 |
650 |
|
2015 |
1100 |
715 |
|
2016 |
1500 |
975 |
|
2017 |
1500 |
975 |
|
2018 |
900 |
585 |
|
2019 |
700 |
455 |
|
2020 |
600 |
390 |
|
After 2020 |
500 |
325 |
With the implementation of good waste management practices
at the site as detailed in Section 7.5.1.5,
adverse environmental impacts are not expected to arise from the storage,
handling and transportation of the general refuse from construction workforce.
7.4.1.5 Summary
Table 7.6
presents a summary of all key types of waste arising during the construction
phase of the Project.
Table 7.6: Summary of Waste Arising during Construction Phase
|
Waste Type |
Key Sources of Waste Generation |
Timing of Waste Generation |
Estimated Quantity of Waste Generation |
Waste Reuse or Disposal |
Waste Handling |
|
Inert C&D Materials |
Majority from excavation work for the WKCD basement (including the
underpass road and the flyover); and minority from
construction of superstructures and substructures (Note: Excavation of marine sediments is
not anticipated) |
Tentatively from 2013 to 2020 |
About 1,910,200 m3 in total |
About 156,400 m3 to be reused on-site as fill
materials for the Park About 905,000 m3 to be reused by two potential
projects, viz., HZMB project and 3rd runway project. Remaining quantity of about 848,800 m3 to be disposed of at the
Government’s PFRFs for beneficial use by other projects in (Note: During the detailed design stage, further
alternative disposal arrangement, e.g., other potential projects that could
receive Inert C&D materials from the WKCD Project, shall be continuously
explored and identified. If no potential projects could receive the surplus
inert C&D materials, the remaining inert C&D materials could be
disposed of at the Government's Public Fill Reception Facilities (PFRFs) for
beneficial use by any other projects in |
Segregate inert C&D materials to avoid contamination from other
waste arising |
|
C&D Materials from Site Clearance |
General site clearance |
Tentatively from 2013 to 2017 |
About 108,300 m3 in total |
Any inert materials segregated from the C&D materials to be reused on-site as far as practicable or disposed of at the Government’s
PFRFs for beneficial use by other projects in Non-inert materials segregated from the C&D materials to be disposed of at the designated landfill sites |
Segregate on site the C&D materials into inert and
non-inert materials |
|
General Refuse |
Waste paper, discarded containers, etc. generated from the site
workforce |
Tentatively from 2013 to 2020 (completion of Phase 1) and
beyond |
0.65 kg per worker per day, the maximum daily arising of general
refuse during the construction period would be approximately 975 kg |
Refuse station for compaction and containerisation and then to
landfill for disposal |
Provide on-site refuse collection points |
|
Chemical Waste |
Used solvents, contaminated rags, waste lubricating oil, etc., from
maintenance and servicing of construction plant and equipment |
Tentatively from 2013 to 2020 (completion of Phase 1) and
beyond |
Few cubic metres per month (preliminary estimate) |
Disposal of at the Chemical Waste
Treatment Centre or other licensed recycling facilities |
Stored on-site by suitably designed containers for off-site disposal
or recycling |
The proposed WKCD is anticipated to involve the following waste generating activities during operation phase:
¡ CACFs and OACFs operation;
¡ Residential activities;
¡ Office activities;
¡ Hotel activities;
¡ Retail stores within WKCD; and
¡ Restaurants within WKCD.
The following types of wastes would be generated from abovementioned activities:
¡ General refuse; and
¡ Chemical waste.
Each type of the above waste arising is discussed below.
7.4.2.1 General Refuse
General
refuse (such as food scraps, waste paper, empty containers, etc) from operation
of WKCD will
mainly be generated from CACFs
and OACFs operation,
residential activities,
office activities,
hotel, retail
stores and
restaurants within WKCD.
Such refuse will
be properly managed by
suitable waste collectors so that intentional or accidental release to
the surrounding environment will
not occur.
The amounts of general refuse generation during
the operation phase have been preliminarily estimated based on the population intake
estimates prepared for the Development Plan of WKCD, and are summarized in Table 7.7.
Table 7.7: Estimation of General Refuse Generation during Operation Phase
|
Item (1) |
Population intake
estimate(1) |
Waste classification(2) |
Per capita disposal rate(3) |
Estimated Waste
Generation |
|
Total Residential
Population |
4,050 |
Domestic waste |
0.87 kg/ person/ day |
3,524 kg/day |
|
Total Employment
Population |
11,777 |
Commercial waste |
0.33 kg/ person/ day* |
3,886 kg/day |
|
Daily Average of Visitors** |
92,160 |
Commercial waste |
0.33 kg/ person/ day* |
30,413 kg/day |
|
Total No. of Hotel Guests |
1,400 |
Commercial waste |
0.33 kg/ person/ day* |
462 kg/day |
Source: (1) Section 7 of
(2) Appendix
1: Classification of Solid Waste and Monitoring Methodology, in Monitoring of Solid Waste in
(3) Plate
2.1 and Plate 2.7, in Monitoring of Solid
Waste in
Note: *Calculated from percentage of
commercial waste over total municipal solid waste, based on municipal solid
waste disposal rate
**Comprising
of CACF, OACF and RDE visitors; visitors to open space not included
Effective
collection of general
wastes will
be implemented to prevent waste materials from creating odour nuisance
or pest/
vermin problem. Waste storage areas will be well maintained and cleaned regularly. To
reduce waste and improve recycling, it is expected that waste such as waste
paper, plastics and aluminium can be segregated for off-site recycling.
7.4.2.2 Chemical Waste
Chemical waste will be generated from various routine maintenance and servicing activities for air conditioning system, emergency generators and other electrical and mechanical equipment. Chemical waste such as waste lubricating oil, contaminated rags, waste paint, used solvents and spent chemicals are expected to be generated from these activities. It is difficult to quantify the amount of chemical waste that will arise from those activities at this stage since it will be dependent on the equipment maintenance requirements and the amount of equipment utilised.
Chemical
wastes may pose environmental, health and safety hazards if not stored and
disposed of in an appropriate manner as stipulated in the Waste Disposal
(Chemical Waste) (General) Regulations. Chemical wastes will
require special handling and storage arrangements in accordance with the relevant
regulations before removal for off-site disposal at the approved Chemical Waste
Treatment Facility or recycling by licensed facilities. Mitigation and control requirements for
chemical wastes are detailed in Section 7.5.2.2. Provided that the handling, storage
and disposal of chemical wastes will
be in accordance with these requirements, adverse environmental impacts will not be expected.
7.5 Mitigation of Adverse Environmental Impact
7.5.1.1 Good Site Practices
Adverse impacts related to waste management such as dust, odour, noise and wastewater discharge will not be expected to arise, provided that good site practices will be strictly followed. Recommendations for good site practices during the construction activities include:
¡ Nomination of an approved person, such as a site manager, to be responsible for good site practices, arrangements for collection and effective disposal to an appropriate facility, of all wastes generated at the site
¡ Training of site personnel in proper waste management and chemical handling procedures
¡ Provision of sufficient waste disposal points and regular collection of waste
¡ Appropriate measures to minimise windblown litter and dust/odour during transportation of waste by either covering trucks or by transporting wastes in enclosed containers
¡ Provision of wheel washing facilities before the trucks leaving the works area so as to minimise dust introduction to public roads
¡ Well planned delivery programme for offsite disposal such that adverse environmental impact from transporting the inert or non-inert C&D materials is not anticipated
7.5.1.2 Waste Reduction Measures
Good management and control can prevent the generation of a significant amount of waste. Waste reduction is best achieved at the planning and design stage, as well as by ensuring the implementation of good site practices. Recommendations to achieve waste reduction include:
¡ Sort inert C&D materials to recover any recyclable portions such as metals
¡ Segregation and storage of different types of waste in different containers or skips to enhance reuse or recycling of materials and their proper disposal
¡ Encourage collection of recyclable waste such as waste paper and aluminium cans by providing separate labelled bins to enable such waste to be segregated from other general refuse generated by the work force
¡ Proper site practices to minimise the potential for damage or contamination of inert C&D materials
¡ Plan the use of construction materials carefully to minimise amount of waste generated and avoid unnecessary generation of waste
In addition to the above measures, specific mitigation measures are recommended below for the identified waste arising to minimise environmental impacts during handling, transportation and disposal of these wastes.
7.5.1.3 Inert and Non-inert C&D materials
In
order to minimise impacts resulting from collection and transportation of inert
C&D materials for off-site disposal, the excavated materials should be
reused on-site as fill
material as far as practicable. In addition, inert C&D materials generated
from excavation works could be reused as fill materials in
local
projects that require public fill for reclamation.
The
surplus inert C&D materials will
be disposed of at the Government’s PFRFs for beneficial use by other projects
in
Liaison with the
CEDD Public Fill Committee (PFC) on the allocation of space for disposal of the
inert C&D materials at PFRF is underway.
No construction work is allowed to proceed until all issues on
management of inert C&D materials have been resolved and all relevant
arrangements have been endorsed by the relevant authorities including PFC and
EPD.
The C&D materials
generated from general site clearance should be sorted on site to segregate any inert
materials for reuse or disposal of at PFRFs whereas the non-inert materials
will be disposed of at the designated landfill site.
In order to monitor the disposal of inert and non-inert C&D materials at respectively PFRFs and the designated landfill site, and to control fly-tipping, it is recommended that the Contractor should follow the Technical Circular (Works) No.6/2010 for Trip Ticket System for Disposal of Construction & Demolition Materials issued by Development Bureau. In addition, it is also recommended that the Contractor should prepare and implement a Waste Management Plan detailing their various waste arising and waste management practices in accordance with the relevant requirements of the Technical Circular (Works) No. 19/2005 Environmental Management on Construction Site.
7.5.1.4 Chemical Waste
If chemical wastes are produced at the construction site, the Contractor will be required to register with the EPD as a chemical waste producer and to follow the guidelines stated in the “Code of Practice on the Packaging Labelling and Storage of Chemical Wastes”. Good quality containers compatible with the chemical wastes should be used, and incompatible chemicals should be stored separately. Appropriate labels should be securely attached on each chemical waste container indicating the corresponding chemical characteristics of the chemical waste, such as explosive, flammable, oxidizing, irritant, toxic, harmful, corrosive, etc. The Contractor should use a licensed collector to transport and dispose of the chemical wastes at the approved Chemical Waste Treatment Centre or other licensed recycling facilities, in accordance with the Waste Disposal (Chemical Waste) (General) Regulation.
Potential environmental impacts arising from the
handling activities
(including storage, collection, transportation and disposal of chemical waste)
are expected to be minimal
with the implementation
of appropriate mitigation measures as recommended.
7.5.1.5 General Refuse
General refuse should be stored in enclosed bins or compaction units separated from inert C&D materials. A reputable waste collector should be employed by the Contractor to remove general refuse from the site, separately from inert C&D materials. Preferably an enclosed and covered area should be provided to reduce the occurrence of 'wind blown' light material.
7.5.2 Operation Phase
7.5.2.1 General Refuse
General refuse should be collected on daily
basis and delivered to the refuse collection point accordingly. A reputable
waste collector should be employed to remove general refuse regularly to avoid odour
nuisance or pest/vermin problem. Sufficient recycling containers are
recommended to be provided at suitable locations of the WKCD site to encourage
recycling of such waste as aluminium cans, plastics and waste paper.
Other general refuse management initiatives including
automatic refuse collection facility would also be considered subject to
further review and investigation.
7.5.2.2 Chemical Waste
If chemical wastes are expected to be produced during the operation phase, the Project Proponent should register with the EPD as a chemical waste producer and follow the guidelines stated in the “Code of Practice on the Packaging, Labelling and Storage of Chemical Wastes”. Good quality containers compatible with the chemical wastes should be used, and incompatible chemicals should be stored separately. Appropriate labels should be securely attached on each chemical waste container indicating the corresponding chemical characteristics of the chemical waste, such as explosive, flammable, oxidizing, irritant, toxic, harmful, corrosive, etc. Licensed collector should be deployed to transport and dispose of the chemical wastes at the approved Chemical Waste Treatment Centre or other licensed recycling facilities, in accordance with the Waste Disposal (Chemical Waste) (General) Regulation.
7.6 Evaluation of Residual Impact
With the implementation of the recommended mitigation measures for the handling, transportation and disposal of the identified waste arising, residual impacts are not expected for both construction and operation phases.
7.7 Environmental Monitoring and Audit
It will be the Contractor’s responsibilities to ensure that all wastes produced during the construction of the Project are handled, stored and disposed of in accordance with good waste management practices and the relevant regulations and requirements. The recommended mitigation measures shall form the basis of the Waste Management Plan to be developed by the Contractor in the construction phase.
During
construction phase, regular site inspection as part of the EM&A
procedures should be carried out to determine if various
types of waste are being managed in accordance with approved procedures and the
Waste Management Plan. It should cover different aspects of waste management
including waste generation, storage, recycling, treatment, transport and
disposal.
7.8.1
Construction
Phase
The major waste types generated by the construction activities will include inert C&D materials from excavation works for the basement (including the underpass road and the flyover) as well as from construction of superstructures and substructures; C&D materials from general site clearance; chemical waste from maintenance and servicing of construction plant and equipment; and general refuse from the workforce. Provided that all these identified wastes are handled, transported and disposed of in strict accordance with the relevant legislative and recommended requirements and that the recommended good site practices and mitigation measures are properly implemented, no adverse environmental impact is expected during the construction phase.
7.8.2 Operation Phase
The key waste types generated during the operation phase will include general refuse from the CACFs and OACFs operation, residential, office, hotel, retail and restaurant activities; as well as chemical waste from regular servicing and maintenance activities for different electrical and mechanical equipment. Provided that all these wastes are handled, transported and disposed of in strict accordance with the relevant legislative requirements and the recommended mitigation measures are properly implemented, no adverse environmental impact is expected during the operation phase.