7.1.1.1
This section identifies potential waste that may arise from
the construction and operation of the EMSD Hong Kong Workshop project and assesses
potential environmental impacts associated with their handling and
disposal. Options of reuse,
minimization, recycling, treatment, storage, collection, transport and disposal
of such wastes have been examined.
Where appropriate, procedures for waste reduction and management have
been considered, with environmental control measures to avoid or minimise
impacts recommended.
7.1.1.2
In addition, as the EMSD Hong Kong Workshop will be
constructed on previously developed land, the potential for contaminated land
which could cause impacts during construction of the facility has also been
assessed.
7.2 Environmental Legislation and Standards
7.2.1
General Waste Management
7.2.1.1
The following legislation is relevant to the handling,
treatment and disposal of waste in HKSAR, and will be considered in assessing
potential impacts and their avoidance or mitigation:
·
Environmental Impact Assessment Ordinance (Cap 499);
·
Waste Disposal (Amendment) Ordinance (Cap 354);
·
Land (Miscellaneous Provisions) Ordinance (Cap 28); and
·
Public Health and Municipal Service Ordinance (Cap 132) –
Public Cleansing and Prevention of Nuisances By-laws.
7.2.1.2
Under the Waste Disposal (Amendment) Ordinance, some of the
regulations are relevant to this EIA, including:
·
Waste Disposal (Charges for Disposal of Construction Waste)
Regulation (Cap 354); and
·
Waste Disposal (Chemical Waste) (General) Regulation (Cap
354).
7.2.2
Waste Disposal
(Amendment) Ordinance and the Waste Disposal
(Charges for Disposal of Construction Waste) Regulation
7.2.2.1
The Waste Disposal (Amendment) Ordinance (WDO) prohibits
unauthorised disposal of wastes.
Schedule 5 of the Waste Disposal (Charges for Disposal of Construction
Waste) Regulation (Charging Regulation) also defines that the inert
construction waste includes rock, rubble, boulder, earth, soil, sand, concrete,
brick, tile, masonry or used bentonite.
7.2.2.2
Under the WDO and the charging regulation, wastes can only
be disposed of at designated waste disposal facilities licensed by the
EPD. For construction work with a
value of more than HK$1 million, the main contractor is required to establish a
billing account at the EPD before transporting the construction waste to the
designated waste disposal facilities (for example, landfill and public
fill). The vessels for delivering
construction waste to the public fill reception facilities require prior
approval from the Public Fill Committee (PFC). Any breach of these regulations may lead
to a fine and/or imprisonment.
7.2.3
Waste Disposal (Chemical
Waste) (General) Regulation
7.2.3.1
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.
7.2.3.2
A person shall not produce, or cause to be produced, any
chemical wastes unless he/she is registered with the EPD, otherwise, it will be
an offence and is liable to a fine and/or imprisonment. Chemical wastes must be treated using
on-site plant as licensed by the EPD or with engaging 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 so as to trace wastes from production to
disposal.
7.2.3.3
This regulation also prescribes the storage facilities to be
provided on-site including the labeling and warning signs. In order to minimise the risks of
pollution and danger to human health and life, waste producers are required to
prepare and make available written emergency procedures for any spillage,
leakage or accidents arising from storage of chemical wastes, and waste
producers must also provide employees with training for such procedures.
7.2.4
Public Cleansing and
Prevention of Nuisances Regulation
7.2.4.1
This regulation provides further control on the illegal
dumping of litter or waste in streets and public places (including water
courses, streams, channels etc).
Any offence of this regulation would result in a fine and/or to
imprisonment.
7.2.5
Other Relevant Guidelines
7.2.5.1
The following guidelines also relate to waste management and
disposal:
·
Technical Memorandum on Environmental Impact Assessment
Process (TM-EIAO), Annex 15 – Guidelines for Assessment of Waste Management
Implications, and Annex 7 – Criteria for Evaluating Waste Management
Implications;
·
Waste Reduction Framework Plan, 1998-2007, Planning
Environment and Lands Branch, Government Secretariat (1998);
·
Waste Disposal Plan for
·
·
Code of Practice on the Packaging, Labeling and Storage of
Chemical Wastes, EPD (1992);
·
New Disposal Arrangement for Construction Waste (1992),
Environmental Protection Department & Civil Engineering Department;
·
Works Branch Technical Circular (WBTC) No. 32/92, The Use of
Tropical Hard Wood on Construction Site;
·
WBTC No. 2/93, Public Dumps;
·
WBTC No. 2/93B, Public Filling Facilities;
·
WBTC Nos.25/99, 25/99A and 25/99C, Incorporation of Information
on Construction and Demolition Material Management in Public Works
Sub-committee Papers;
·
WBTC No. 12/2000, Fill Management,
·
WBTC Nos. 6/2002 and 6/2002A, Enhanced Specification for
Site Cleanliness and Tidiness. Works Bureau,
·
WBTC No. 12/2002, Specification Facilitating the Use of
Recycled Aggregates. Works Bureau,
·
ETWB TC(W) No. 33/2002 Management of Construction and
Demolition Material Including Rock;
·
DevB TC(W) No. 6/2010, Trip Ticket System for Disposal of
Construction & Demolition Materials, Development Bureau,
·
ETWB TC(W) No. 19/2005 Environmental Management on
Construction Sites.
7.2.5.2
The ETWB TC(W) No. 19/2005 also sets out the policy and
procedures requiring contractors to prepare and implement an environmental
management plan to encourage on-site sorting of C&D materials and to reduce
C&D waste generation during construction.
7.2.6
Contaminated Land
7.2.6.1
The following legislation relevant to the land contamination
issues as a result of handling, treatment and disposal of contaminated
materials:
·
Environmental Impact Assessment Ordinance (Cap 499);
·
Waste Disposal Ordinance (Cap 354);
·
Waste Disposal (Chemical Waste) (General) Regulation (Cap
354C); and
·
Dangerous Goods Ordinance (Cap 295).
7.2.6.2
The following EPD publications provide guidance on the land
contamination assessment in this Assignment:
·
Code of Practice of the Packaging, Labelling and Storage of
Chemical Waste, EPD (1992).
·
Practice Guide for Investigation and Remediation of
Contaminated Land
·
Guidance Note for Contaminated Land Assessment and
Remediation; and
·
Guidance Manual for Use of Risk-Based Remediation Goals
(RBRGs) for Contaminated Land Management.
7.3.1.1
The assessment of the environmental impacts from the
handling, storage, collection, transportation and disposal of waste material
generated by the project has been undertaken in accordance with Annex 7 and
Annex 15 of the TM-EIAO.
7.3.1.2
The waste management hierarchy has been applied in the
assessment and development of mitigation measures for waste. The waste management hierarchy is a
concept which shows the desirability of various waste management methods and comprises
the following in order of preference:
·
avoidance;
·
minimisation;
·
recycling/reuse;
·
treatment; and
·
disposal.
7.3.1.3
All opportunities for reducing waste generation have been
assessed based upon the following factors:
·
avoiding or minimising waste generation through changes in
the design;
·
adopting better management practices to promote segregation
of waste materials;
·
reuse and recycling; and
·
diverting waste to public dumps or other construction sites.
7.3.1.4
The types and quantities of waste have been estimated and
disposal options for each category of waste identified, taking into account the
existing or future spare capacities of the waste disposal facilities and the
environmental implications of the handling, collection and disposal of waste
material. The potential environmental impacts associated with the handling,
transportation and disposal of waste arising from the construction works will
be assessed with reference to the following approach:
·
estimation of the types, timing and quantities of the wastes
to be generated and fill to be imported; and
·
assessment of the potential environmental impacts on the
capacity of waste collection, transfer and disposal facilities.
7.3.1.5
The impact caused by handling (including stockpiling,
labelling, packaging and storage), collection, transportation and
re-use/disposal of wastes has been addressed in detail and appropriate
mitigation measures have been proposed.
This assessment covers the following areas: potential hazard, air and
odour emissions, noise, wastewater discharge and public transport.
7.3.2
Construction Phase Waste
Management Assessment
Waste Types
7.3.2.1
The construction of the EMSD Hong Kong Workshop will involve
a number of activities which will generate wastes which can broadly be
classified into distinct categories based on their nature and the options for
their disposal. These include:
·
Excavated construction and demolition (C&D) materials
suitable for public fill (no excavation of marine sediment would occur in this
Project);
·
Construction and demolition waste, including some cleared
vegetation, which is not suitable for public fill;
·
Chemical waste; and
·
General refuse.
Details of Work Activities
7.3.2.2
As described in Section 3 of this
EIA report, the EMSD Hong Kong Workshop project comprises mainly the construction
of a land-based steel shed structure on a raft foundation. Upon site clearance, site formation
works will be carried out which involves the excavation of soil for the subsequent
construction of concrete slab and footing, erection of formwork and cover shed,
plant rooms, utilities and finally installation of building services.
Construction and Demolition Materials
7.3.2.3
Construction and demolition
(C&D) materials generated during construction will comprise materials that
are suitable for reuse on site or as public fill and a portion of waste
material that will require disposal to a licensed landfill facility. For the purposes of this assessment,
these two fractions are denoted C&D material and C&D waste and are
discussed below.
C&D Materials
7.3.2.4
The Construction and Demolition (C&D)
materials generated from the EMSD Hong Kong Workshop project will comprise excavated materials mainly
from the construction of raft foundation, concrete footing and slab, utilities
trenches.
7.3.2.5
In accordance with the waste
hierarchy presented in Section 7.3.1, it is necessary to consider all ways to avoid
the generation of material and also reuse within the project. The following methods have been adopted:
·
Minimising Generation of
C&D Materials: Section 2 of this EIA report presented that the design of
this workshop has taken into account the environmental benefits arising from an
optimized design of the workshop, in particular the adoption of a simple open
steel shed design instead of a typical building design of the workshop so as to
reduce the C&D materials and wastes to be generated.
·
Maximising Use of C&D
Materials:
Inert C&D materials from the site formation works will be reused both
on-site and off-site as far as practicable, e.g. scrapped steel bars to be
recycled; earth materials, concrete debris and aggregates for backfilling, etc.
7.3.2.6
A summary of the C&D materials
anticipated to arise from the project is provided in Table 7.1 below.
Table 7.1 Summary
of C&D Materials Arising from the Project
|
Material Type |
Quantity (tonne) |
Remarks |
|
Excavated soil |
150 |
Generated from
the excavation works for the construction of raft foundation and concrete footing. |
|
Concrete debris
and aggregate |
70 |
Generated from
the construction of raft foundation and concrete footing. |
|
Scrap steel |
0.15 |
Generated from
the construction of raft foundation, concrete footing, steel formwork of shed
structure. |
|
TOTAL |
220.15 |
|
7.3.2.7
Some of the C&D material
generated by the project has been explored for reuse either on-site or off-site. All scrap steel will be collected for
recycling. It is estimated that
approximately 20 tonne of sand and aggregate would also be reused on-site. The possibility of maximizing the reuse
of excavated soil would be explored during the detailed design phase of the
Project. Approximately 75 tonnes of
the excavated soil can be reused as backfill upon the completion of the raft
foundation works. As some of the
materials would be reused on-site, impacts from transportation would be minimised.
7.3.2.8
The balance of approximately 75
tonnes of excavated soil and 50 tonne of construction debris is proposed to be delivered
to the Tseung Kwan O Area 137 Fill Bank via the adjacent Chai Wan Public Fill
Barging Point at
7.3.2.9
However, the material will need to
be carefully stockpiled if it cannot be reused or removed directly to avoid
dust and other nuisance impacts. 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
agreed between the responsible Government department and party.
C&D Waste
7.3.2.10 In
addition to the C&D materials that will be generated by the project and
will be suitable for reuse as public fill, some C&D waste will be generated
during the construction phase.
These materials will include:
·
Cleared vegetation;
·
Wood from formwork;
·
Unusable cement mixes; and
·
Damaged or contaminated construction materials.
7.3.2.11 The
volume of C&D waste generated by the project will be dependant on specific
operating procedures and site practices and, is expected to be small at about 10
tonnes. In addition, as the EMSD Hong
Kong Workshop is a relatively minor facility covering a small area which has
mostly been cleared, the amount of C&D waste generated from site clearance
comprising a mixture of topsoil and vegetative matter is expected to be small.
7.3.2.12 The
other types of C&D waste are, also, expected to be limited, with only small
quantities of maintenance and packaging waste being generated. Given that the material will be
generated will be of in small quantities, significant impacts associated with
its handling and disposal would not be expected.
7.3.2.13 Measures
to minimise the generation of waste shall be implemented and demolition waste
shall be sorted to avoid contamination of the materials suitable for public
fill but significant impacts would not be anticipated from the handling,
storage or disposal of this material.
7.3.2.14 Chemical
wastes likely to arise from the construction activities for the EMSD Hong Kong Workshop
would include:
·
Scrap batteries or acid/alkali from maintenance activities;
·
Used paints, engine oils, hydraulic fluids and waste fuel;
·
Spent mineral oils/cleansing fluids from machineries; and
·
Spent solvents/solutions, some of which may be halogenated,
from equipment cleansing activities.
7.3.2.15
Chemical wastes may pose
environmental, health and safety hazards if not stored and disposed of
appropriately as outlined in the Waste Disposal (Chemical Waste) (General)
Regulation and the Code of Practice on the Packing, Labeling and Storage of Chemical Waste. These hazards may include:
·
Toxic effects to workers;
·
Adverse effects on air quality, water quality and land
contamination due to spillage;
·
Hazards of fire; and
·
Disruption of sewage treatment works should the chemical
waste enter the sewerage system.
7.3.2.16 The
amount of chemical waste would be estimated to be approximately 100L for the
whole project, depending on the Contractor’s on-site maintenance practices and
the number of mechanical plant and vehicles utilised on-site. However, it is anticipated that the
quantity of chemical waste arising during the construction of this project
would be very small given the small scale of the project and if handled,
stored, transported and disposed of in an appropriate manner, impacts would not
be anticipated.
7.3.2.17 Notwithstanding,
the Contractor should register to the EPD as a Chemical Waste Producer pursuant
to the Regulation and the chemical waste should be collected by licensed
collectors for subsequent disposal at licensed waste disposal facilities, for
example the Chemical Waste Treatment Centre in Tsing Yi.
7.3.2.18 The
presence of the construction site with workers and the site office would
generate a variety of general refuse which will need disposal, consisting mainly
of food waste, aluminum cans, waste paper, etc.
7.3.2.19 The
storage of general refuse has the potential to cause adverse environmental
impacts, e.g. odour nuisance if the waste is not collected frequently,
windblown litter, water quality impacts if the waste enters water bodies,
visual impacts, etc. Construction
sites may also attract pests, vermin and other disease vectors if the waste
storage areas were not well maintained.
Disposal of waste at areas other than approved refuse transfer stations
and landfills can also lead to similar adverse impacts.
7.3.2.20 The
number of workforce (clerical and workers) to be employed for the EMSD Hong
Kong Workshop project is expected to be approximately 12 people per day over the
14 month construction period. 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 8kg
only (or approximately 3 tonnes for the entire construction period). Provided that mitigation measures are
adopted, potential environmental impacts caused by the storage, handling,
transport and disposal of general refuse would be expected to be
insignificant. It is recommended
that the general refuse should be collected on a daily basis and transferred to
the adjacent Island East Refuse Transfer Station at
7.3.3
Operational Phase Waste
Management Assessment
7.3.3.1
The operational phase of the EMSD Hong
Kong Workshop project is not be expected to generate any significant quantities
of waste.
7.3.3.2
The quantities of general refuse
arising from the project at this stage will be low and mainly arise from office
activities and the vehicle maintenance activities. Quantities of waste and chemical waste
e.g. lubrication oil, used batteries, etc are likely to be generated but the
quantities will be small and insignificant. Standard good operating practice
requirements should be followed in the storing, handling and transporting of
any chemical wastes.
7.3.3.3
The chemical waste likely to be
generated in the operation of the EMSD Hong Kong Workshop would mainly arise
from the repairing and maintenance of vehicles, including scrap batteries or
spent acid/alkali, used engine oils, lubricating and hydraulic fluids and waste
fuel, and spent mineral oils/ cleaning fluids from mechanical machinery. However, the quantity of chemical waste
arising will be limited and proper management procedures should be followed
according to the EPD’s Code of Practice of the Packaging, Labelling and Storage
of Chemical Waste.
7.3.3.4
Based upon the above, significant
waste implications during the operational phase would not be anticipated.
7.3.4.1
Mitigation measures are required
to ensure the proper handling, storage, transportation and disposal of waste being
carried out during both construction and operation phases of this project. Also, measures to ensure that the
generation of waste is avoided and minimised and that waste materials are
recycled and treated as far as practicable. The recommended mitigation measures for
all categories of waste are as follows.
With proper implementation of these measures, the handling (including
stockpiling, labelling, packaging & storage), collection, transportation
and re-use/disposal of wastes will not casue adverse impacts on potential
hazard, air and odour emissions, noise, wastewater discharge, ecology and
public transport.
(i)
The requirements as stipulated in the ETWB TC(W) No.19/2005
Environmental Management on Construction Sites and the other relevant
guidelines should be included in the Particular Specification for the
Contractor as appropriate.
(ii)
The EMSD Hong Kong Workshop Contractor should be requested
to submit a Waste Management Plan (WMP) prior to the commencement of
construction work, in accordance with the ETWB TC(W) No.19/2005 so as to
provide an overall framework of waste management and reduction. The WMP should include:
-
Waste management policy;
-
Record of generated waste;
-
Waste reduction target;
-
Waste reduction programme;
-
Role and responsibility of waste
management team;
-
Benefit of waste management;
-
Analysis of waste materials;
-
Reuse, recycling and disposal
plans;
-
Transportation process of waste
products; and
-
Monitoring and action plan.
(iii)
The waste management hierarchy below should be strictly
followed. This hierarchy should be
adopted to evaluate the waste management options in order to maximise the
extent of waste reduction and cost reduction. The records of quantities of waste
generated, recycled and disposed (locations) should be properly
documented.
(iv)
A trip-ticket system should be established in accordance
with DevB TC(W) No. 6/2010 and 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
would be included as one of the contractual requirements for the Contractor to
strictly implement. The Engineer
would also regularly audit the effectiveness of the system.
(v)
A recording system for the amount of waste generated,
recycled and disposed (locations) should be established. The future Contractor should also
provide proper training to workers regarding the appropriate concepts of site
cleanliness and waste management procedures, e.g. waste reduction, reuse and
recycling all the time.
(vi)
The CEDD should be timely notified of the estimated volumes of
excavated materials to be generated and the Public Fill Committee should be
notified and agreement sort on the disposal of surplus inert C&D
materials. Wherever practicable,
C&D materials should be segregated from other wastes to avoid contamination
and to ensure acceptability at public filling areas or reclamation sites.
(vii)
The site and surroundings shall be kept tidy and litter
free.
(viii)
No waste shall be burnt on-site.
(ix)
Make provisions in contract documents to allow and promote
the use of recycled aggregates where appropriate.
(x)
Prohibit the Contractor to dispose of C&D materials at
any sensitive locations e.g. natural habitat, etc. The Contractor should propose the final
disposal sites in the EMP and WMP for approval before implementation.
(xi)
Stockpiled material shall be covered by tarpaulin and /or
watered as appropriate to prevent windblown dust and surface run off.
(xii)
Excavated material in trucks shall be covered by tarpaulins
to reduce the potential for spillage and dust generation.
(xiii)
Wheel washing facilities shall be used by all trucks leaving
the site to prevent transfer of mud onto public roads.
(xiv)
Standard formwork or pre-fabrication should be used as far
as practicable so as to minimise the C&D materials arising. The use of more durable formwork or
plastic facing for construction works should also be considered. The use of wooden hoardings should be
avoided and metal hoarding should be used to facilitate recycling. Purchasing of construction materials
should be carefully planned in order to avoid over-ordering and wastage.
(xv)
The Contractor should recycle as many C&D materials as
possible on-site. The public fill
and C&D waste should be segregated and stored in separate containers or
skips to facilitate the reuse or recycling of materials and proper
disposal. Where practicable, the
concrete and masonry should be crushed and used as fill materials. Steel reinforcement bar should be
collected for use by scrap steel mills.
Different areas of the sites should be considered for segregation and
storage activities.
(xvi)
Chemical waste producers should register with the EPD. Chemical waste should be handled in
accordance with the Code of Practice on the Packaging, Handling and Storage of
Chemical Wastes as follows:
-
suitable for the substance to be
held, resistant to corrosion, maintained in good conditions and securely
closed;
-
Having a capacity of <450L
unless the specifications have been approved by the EPD; and
-
Displaying a label in English and
Chinese according to the instructions prescribed in Schedule 2 of the
Regulations.
-
Clearly labelled and used solely
for the storage of chemical wastes;
-
Enclosed with at least 3 sides;
-
Impermeable floor and bund with
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;
-
Adequate ventilation;
-
Sufficiently covered to prevent
rainfall entering (water collected within the bund must be tested and disposed
of as chemical waste, if necessary); and
-
Incompatible materials are
adequately separated.
(xvii)
Waste oils, chemicals or solvents shall not be disposed of
to drain.
(xviii)
Adequate numbers of portable toilets should be provided for
on-site workers. Portable toilets
should be maintained in reasonable states, which will not deter the workers
from utilising them. Night soil
should be regularly collected by licensed collectors.
(xix)
General refuse arising on-site should be stored in enclosed
bins or compaction units separately from C&D and chemical wastes. Sufficient dustbins shall be provided
for storage of waste as required under the Public Cleansing and Prevention of
Nuisances By-laws. In addition, general
refuse shall be cleared daily and shall be disposed of to the nearest licensed
landfill or refuse transfer station.
Burning of refuse on construction sites is prohibited.
(xx)
All waste containers shall be in a secure area on
hardstanding;
(xxi)
Aluminium cans are usually collected and recovered from the
waste stream by individual collectors if they are segregated and easily
accessible. Separately labelled
bins for their deposition should be provided as far as practicable.
(xxii)
Office wastes can be reduced by recycling of paper if such
volume is sufficiently large to warrant collection. Participation in a local collection
scheme by the Contractor should be advocated. Waste separation facilities for paper,
aluminium cans, plastic bottles, etc should be provided on-site.
(xxiii)
Training shall be provided to workers about the concepts of
site cleanliness and appropriate waste management procedure, including waste
reduction, reuse and recycling.
7.3.5
Waste Disposal
Recommendations
7.3.5.1
Based upon the estimated
quantities and types of waste to be generated by the project, disposal options
have been proposed, as detailed in Table 7.2 below. In terms of the disposal of small
quantities of general refuse, WENT Landfill via the nearby Island East Refuse
Transfer Station is recommended. In
terms of the delivery of excavated C&D materials, the TKO Area 137 Fill
Bank via the Chai Wan Public Fill Barging Point is recommended. Chemical wastes will be disposed of at
the Chemical Waste Treatment Centre in Tsing Yi or other licensed facilities via
licensed collectors.
Table
7.2 Recommended
Waste Disposal Sites
|
Type of Waste |
Disposal Site |
Quantity |
|
C&D materials |
TKO Area 137 Fill Bank |
Excavated soil: ~75 tonnes Construction debris:
~50 tonnes |
|
C&D waste (plastics, glass,
wood, including cleared vegetation etc.) |
SENT Landfill |
~10 tonnes |
|
Chemical waste (as defined under
Schedule 1 of the Waste Disposal (Chemical Waste) Regulation) |
Chemical Waste Treatment Centre in
Tsing Yi or other licensed facilities via licensed collectors |
~100 L |
|
General refuse |
WENT Landfill via |
~3 tonnes |
7.4.1.1
The assessment for land contamination of the Project site was
carried out with reference to the EPD’s Practice Guide for Investigation and Remediation
of Contaminated Land. The normal sequence
of steps involved in the assessment process is summarized below:
1.
Carrying out the site appraisal (information collection);
2.
Designing site investigation and preparing the Contamination
Assessment Plan (CAP) for EPD’s approval;
3.
Conducting the site investigation;
4.
Interpreting results and preparing the Contamination
Assessment Report (CAR) for EPD’s approval;
5.
Planning and designing the remediation works and preparing
the Remediation Assessment Plan (RAP) for EPD’s approval;
6.
Carrying out the remediation works; and
7.
Preparing the Remediation Report (RR) for EPD’s
endorsement.
7.4.2
Assessment Findings from Site
Appraisal
7.4.2.1
The site appraisal was conducted to identify whether there
were any potential contamination sources that may have impacted the site. The usual sequence of the site appraisal
process is summarized below:
1.
Identification of the site’s future land use and
applicable Risk-Based Remediation Goals (RBRGs) for the land use scenarios;
2.
Review of historical information;
3.
Health and safety risk assessment and planning for
site walkover;
4.
Site walkover;
5.
Identification of sources of contamination /
chemical of concern;
6.
Design and plan site investigation programme;
7.
Health and safety risk assessment and planning; and
8.
Prepare CAP for EPD’s approval.
Identification of the Site’s Future Land Use
7.4.2.2
According to the EPD’s RBRGs Guidance Manual, the Project site’s
future land use was determined as “Industrial” for the subsequent
identification of the corresponding RBRGs.
The conceptual site model (industrial) was therefore selected based on Annex
B of EPD’s Practice Guide for Investigation and Remediation of Contaminated
Land, which served as a reference during this site appraisal exercise to
identify contamination sources, exposure pathways and receptors for the site to
ensure that no additional pathways or receptors exist for the site and that the
selected RBRGs can be applied.
Review of Historical Information
7.4.2.3
Information including the history and other available information
regarding the Project site was reviewed in order to identify the potential
current and historical, on-site and off-site activities that could result in
contamination of the Project site, including
·
Potentially contaminating activities that have occurred at
the site such as storage and handling of chemicals, oil and/or hazardous waste,
on-site waste disposal, burn pits, etc.
There may have been different activities over time which may have caused
contamination, all of which should be noted.
·
Storage facilities, pipelines, collection sumps for
chemicals, oil and/or hazardous wastewater/waste that are or were present on
the site.
·
Accidents, fires, explosions, spillages and any pollution
incidents attributed to the site and any remediation that has occurred at the
site or neighbouring areas.
·
Other site information should include geological and
hydrogeological characteristics of the site.
7.4.2.4
With reference to Annexes C1 and C2 of EPD’s Practice Guide
for Investigation and Remediation of Contaminated Land, the information on the present
activities and past land use history in relation to any possible land
contamination were collated and included in Appendix 7.1 of this EIA report. The key details are summarised below:
Historic Land Use
·
Before 1984: Marine
environment
·
1984-1985: Reclamation
·
1987-1996: Wing
Tai Temporary Housing Area
·
1996-2003: Vacant
·
2003-2004: Temporary
general storage area of Drainage Services Department
·
2005-2008: Temporary
general storage area of Drainage Services Department and Food and Environmental
Hygiene Department
·
Since 2008: Vacant
·
The Fire Services Department (FSD) also informed that there
was no record of storage of dangerous goods (DGs) at the Project site and no
incident of chemical leakage and spillage of DGs.
Existing Land Use
·
The project site is currently vacant.
Site Walkover
7.4.2.5
Two site walkover events were conducted on 8 and 16
September 2011 at the Project site and the details of the site walkover events
are also included in Appendix 7.1 of
this EIA report. The findings indicated
that there were no potential sources and signs of contamination, e.g.
chemicals, oils and hazardous waste handling and storage locations, bulk
storage tanks, sumps, pipelines, staining, decolouration, distressed
vegetation, etc.
Conclusion from Site Appraisal
7.4.2.6
Based on the recorded nature of past and present land use
activities, it is anticipated that there were no potentially contaminating
activities occurred, such as storage and handling of chemicals, oils and/or
hazardous waste, on-site waste disposal, burn pits, storage facilities,
pipelines, collection sumps for chemicals, oils and/or hazardous
wastewater/waste, accidents, fires, explosions, spillages and any pollution
incidents, etc. As such, it was
considered not necessary to continue Steps (5), (6), (7) and (8) for the Site
Appraisal. As no potential land
contamination sources and issues were identified, the CAP was considered not
required for the contamination assessment for the construction phase of this
Project in this EIA study.
7.4.3
Preventive Measures
during Operation Phase
7.4.3.1
According to Section 3 of this EIA report, the following
potential sources of land contamination during the operation of this proposed
workshop were identified which are relevant to the storage and use of chemicals:
·
Repairing and maintenance areas inside the workshop;
·
DGs and chemical storage areas; and
·
Chemical waste storage area.
Preventive and Precautionary Plan
Storage of Chemicals and Chemical
Wastes
7.4.3.2
Chemicals and chemical wastes should be stored in
purpose-built storage areas. For
chemicals classified as DGs under the Dangerous Goods Ordinance, all
segregation, storage and handling should comply with the requirements of EPD’s
Code of Practice on the Packaging, Labeling and Storage of Chemical Waste. The same preventative approach should apply
to the storage of any raw solid and liquid chemicals and chemical wastes.
Emergency Procedures
7.4.3.3
Any spillage should be reported to the Workshop Manager who should
attend to the spillage and initiate any immediate actions required to protect
workers and to confine and clean up the spillage.
Spillage/Leakage of Liquid
Chemical/Waste at Storage Area
7.4.3.4
Where the spillage/leakage is contained in the enclosed
storage area, the material should be transferred to suitable containers by
appropriate equipment, e.g. hand-operated pumps, scoops or shovels. If the
spillage/leakage quantity is small, it should be covered and mixed with
suitable absorbing materials. The resultant slurry should be treated as
chemical waste and transferred to suitable containers for disposal.
Spillage/Leakage at Repairing and
Maintenance Areas
7.4.3.5
For spillage/leakage in other areas, immediate action should
be taken to contain the spillage/leakage.
Suitable absorbing materials should be used as appropriate to cover the
spill. The slurry should be treated as chemical wastes and transferred to
containers for proper disposal.
Areas that were contaminated by chemical waste spillage/leakage should be
decontaminated. For aqueous
chemicals or wastes and water soluble organic wastes, water should be used to
clean the contaminated area. For
organic chemical wastes that are not soluble in water, kerosene or turpentine should
be used. Wastes from the cleanup operation should be treated and disposal of as
chemical wastes.
Record of Incidents
7.4.3.6
A detailed incident report should be compiled by Workshop
Manager as soon as possible after any incident. The report should contain the details of
the incident, including an estimate of any amounts spilled, and any actions
taken. The incident report should be used to evaluate any environmental impacts
due to the spillage and to assess the effectiveness of the measures taken, so
that improvements can be made to the response procedures for future incidents.
Procedures for Disposal of Wastes
7.4.3.7
Used or expired chemicals, deteriorated synthetic lube oil,
expired or non-usable paint and similar materials should be managed according
to EPD’s Code of Practice of the
Packaging, Labelling and Storage of Chemical Waste, and collected by a licensed
collector and disposed of at a licensed chemical treatment facility. To avoid
prolonged storage of chemical waste on site which may increase the potential
for land contamination, waste should be removed from the Workshop on a regular
basis.
7.5.1.1
Assuming all the mitigation
measures are implemented, adverse residual impacts would not be anticipated from
the handling, storage, transportation or disposal of the waste generated by the
project are predicted, even though the operation would be extended beyond July
2017 as planned.
7.5.1.2
In addition, no significant
contaminated land impacts are predicted during the construction and operation
phases and as such, adverse residual impacts would not be anticipated, even though the
operation would be extended beyond July 2017 as planned.
7.6 Environmental Monitoring and Audit
7.6.1.1
The assessment has concluded that
the handling, transportation and disposal of waste materials during
construction will not give rise to significant impacts if appropriate
mitigation measures are implemented.
However, it is recommended that during construction phase, regular site
inspections and supervision of the waste management procedures shall be
undertaken as part of the EM&A procedures, to ensure proper control, that all
waste is removed from the site area as appropriate and illegal disposal of
waste is not being undertaken.
Waste EM&A during the operation phase is not required and, also, as contaminated
land impacts are not predicted, no EM&A for contaminated land is
recommended. Further details of the
specific construction phase EM&A requirements are detailed in Section 10 of
this report and in the EM&A Manual.
7.7.1.1
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 (on-site and off-site) etc.,
have been devised in the construction methodology to minimise the surplus
materials to be disposed off-site.
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 of
measures 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 operation phase have
been assessed. Recommendations have
been made to ensure proper treatment and disposal of these wastes. 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 agreed between the responsible Government
department and party. Adverse residual
impact would not be anticipated during both the construction and operation
phases of this Project, even though the operation would be extended beyond July
2017 as planned.
7.7.1.2
There were no sources of historic land contamination issues
associated with the Project site.
For the future operation of this workshop, with the implementation of
the preventive and precautionary plan as recommended in this EIA study, land
contamination impact would not be anticipated, even though the operation would
be extended beyond July 2017 as planned.