5.1
Waste management will be the contractor’s responsibility 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 EPD’s
regulations and requirements. The contractor
will be required to ensure that loss of dredged material does not take place
during transportation of the material in barges to the designated marine
disposal ground.
5.2
Other waste materials generated during construction activities, such as
construction and demolition (C&D) materials, chemical wastes and general
refuse from the workforce, are recommended to be audited at regular intervals
(at least monthly) to ensure that proper storage, transportation and disposal
practices are being implemented. This
monitoring of waste management practices will ensure that these solid and
liquid wastes generated during construction are not disposed of into the
surrounding marine waters. The
Contractor will be responsible for the implementation of any mitigation measures
to minimise waste or redress problems arising from the waste materials.
Marine Sediments
5.3
The basic
requirements and procedures for dredged mud disposal are specified under the
WBTC No. 3/2000. The management of the
dredging, use and disposal of marine mud is monitored by the Marine Fill
Committee (MFC), while the licensing of marine dumping is the responsibility of
the Director of Environmental Protection (DEP).
5.4
The dredged marine
sediments will be loaded onto barges and transported to designated disposal
sites depending on their level of contaminants. CED have advised that the uncontaminated mud can be disposed at
the South Cheung Chau marine disposal ground.
The contaminated material, however, must be dredged and transported with
great care. Therefore appropriate
dredging methods should be incorporated into the water quality mitigation
measures, such as the use of closed-grab dredgers. Furthermore, the dredged contaminated sediment must be
effectively isolated from the environment upon final disposal and shall be
disposed at the East Sha Chau Contaminated Mud Pits which is designated for the
disposal of contaminated mud. In
accordance with the requirements of WBTC No. 3/2000, the project proponent
shall submit a formal Sediment Quality Report to DEP at least 3 month prior to
the dredging contract being tendered.
5.5
During
transportation and disposal of the dredged marine sediments, the following
measures shall be taken to minimize impacts on water quality:
·
Bottom opening of barges
shall be fitted with tight fitting seals to prevent leakage of material. Excess material shall be cleaned from the
decks and exposed fittings of barges and hopper dredgers before the vessel is
moved.
·
Monitoring of the barge
loading shall be conducted to ensure that loss of material does not take place
during transportation. Transport barges
or vessels shall be equipped with automatic self-monitoring devices specified
by the DEP.
Good Site Practices and Waste Reduction Measures
5.6
It is not
anticipated that adverse waste management related impacts would arise, provided
that good site practices are strictly followed. Recommendations for good site practices during the construction
activities include:
·
Use authorized or licensed waste haulier to collect specific category of
waste;
·
Obtain the necessary waste disposal permits from the appropriate
authorities, if they are required, in accordance with the Waste Disposal Ordinance (Cap 354, Waste Disposal (Chemical Waste)
(General) Regulation (Cap 354), the Land (Miscellaneous Provision) Ordinance
(Cap 28);
·
nomination of an approved personnel, 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 for
disposal;
·
appropriate measures to minimise windblown litter and dust during
transportation of waste by either covering trucks or by transporting wastes in
enclosed containers;
·
separation of chemical wastes for special handling and appropriate
treatment at the CWTF;
·
regular cleaning and maintenance programme for drainage systems, sumps
and oil interceptors; and
·
a recording system for the
amount of wastes generated, recycled and disposed of (including the disposal
sites).
·
In order to monitor the
disposal of C&D and solid wastes at public filling facilities and landfills,
and control fly-tipping, a trip-ticket system should be included as one of the
contractual requirements and implemented by the Environmental Team. One may make reference to WBTC No. 5/99 for
details; and
·
A Waste Management Plan (WMP)
should be prepared and this WMP should be submitted to the Engineer for
approval. One may make reference to
WBTC No. 29/2000 for details.
5.7
Good management
and control can prevent the generation of significant amount of waste. Waste reduction is best achieved at the
planning and design stage, as well as by ensuring the implementation of good
site practices. Recommendations to
achieve waste reduction include:
·
segregation and storage of different types of waste in different
containers, skips or stockpiles to enhance reuse or recycling of materials and
their proper disposal;
·
to encourage collection of aluminium cans by individual collectors,
separate labelled bins shall be provided to segregate this waste from other
general refuse generated by the work force;
·
any unused chemicals or those with remaining functional capacity shall
be recycled;
·
use of reusable non-timber formwork to reduce the amount of C&D
material;
·
prior to disposal of C&D waste, it is recommended that wood, steel
and other metals shall be separated for re-use and / or recycling to minimise
the quantity of waste to be disposed of to landfill;
·
proper storage and site practices to minimise the potential for damage
or contamination of construction materials; and
·
plan and stock construction
materials carefully to minimize amount of waste generated and avoid unnecessary
generation of waste.
5.8
In addition to the
above good site practices and waste reduction measures, specific mitigation
measures are recommended below for the identified waste arisings to minimise
environmental impacts during handling, transportation and disposal of these
wastes. The transportation of these
wastes by barge to the disposal location is recommended, as far as practicable,
in order to reduce potential noise and air quality impacts from road
transportation.
Construction and Demolition Waste
5.9
Careful design,
planning and good site management can minimize over-ordering and generation of
waste materials such as concrete, mortar and cement grouts. The design of formwork should maximize the
use of standard wooden panels so that high reuse levels can be achieved. Alternatives such as steel formwork or
plastic facing should be considered to increase the potential for reuse.
5.10
The contractor
should use as much of the C&D material as possible on-site. Proper segregation of waste types on site
will increase the feasibility of certain components of the waste stream by
recycling contractors.
5.11
To maximize
landfill life, Government policy discourages the disposal of C&D wastes
with more than 20% inert material (by volume) at landfill. Inert C&D material (public fill) are
directed to reclamation areas, where they have the added benefit of offsetting
the need for removal of materials from borrow areas for reclamation purposes,
or to an approved public filling area (PFA).
Due to limited space at landfills, disposal at reclamation sites or a
PFA would be the preferred method.
Chemical Waste
5.12
After use,
chemical wastes should be handled according to the Code of Practice on the Packaging,
Labeling and Storage of Chemical Wastes.
Spent chemicals should be stored and collected by an approved operator
for disposal at the Chemical Waste Treatment Facility or other licensed
facility in accordance with the Chemical Waste (General) Regulation.
5.13
Containers used
for the storage of chemical waste should:
·
Be suitable for the substance
they are holding, resistant to corrosion, maintained in good condition, and
securely closed;
·
Have a capacity of less than
450 litres unless the specifications have been approved by the EPD; and
·
Display a label in English
and Chinese in accordance with instructions prescribed in Schedule 2 of the
Regulations.
5.14
Containers used
for the storage of chemical waste should:
·
Be suitable for the substance
they are holding, resistant to corrosion, maintained in good condition, and
securely closed;
·
Have a capacity of less than
450 litres unless the specifications have been approved by the EPD; and
·
Display a label in English
and Chinese in accordance with instructions prescribed in Schedule 2 of the
Regulations.
5.15
The storage area
for chemical waste should:
·
Be clearly labeled and used
solely for the storage of chemical waste;
·
Be enclosed on at least 3
sides;
·
Have an impermeable floor and
bunding, of capacity to accommodate 110% of the volume of the largest container
or 20% by volume of the chemical waste stored in that area, whichever is the
greatest;
·
Have adequate ventilation;
·
Be covered to prevent
rainfall entering (water collected within the bund must be tested and disposal
as chemical waste if necessary); and
·
Be arranged so that
incompatible materials are adequately separated.
5.16
Disposal of
chemical waste should:
·
Be via a licensed waste
collector; and
·
Be a facility licensed to receive
chemical waste, such as the Chemical Waste Treatment Facility which offers a
chemical waste collection service and can supply the necessary storage
containers; or
·
Be a reuser of the waste,
under approval from the EPD.
5.17
The Center for
Environmental Technology operates a Waste Exchange Scheme which can assist in
finding receivers or buyers for the small quantity of chemical waste to be
generated from the Project.
General Refuse
5.18
General refuse
should be stored in enclosed bins or compaction units separate from C&D and
chemical wastes. A reputable waste
collector should be employed by the contractor to remove general refuse from
the site, separately from C&D and chemical wastes, on a daily or every second
day basis to minimize odour, pest and litter impacts.
5.19
Aluminum cans are
often recovered from the waste stream by individual collectors if they are
segregated or easily accessible, so separate labeled bins for their deposit
should be provided if feasible. Site
office waste can be reduced through recycling of paper if volumes are large
enough to warrant collection.
Participation in a local collection scheme should be considered if one
is available.
5.20
The implementation
schedule of the recommended mitigation measures is presented in Appendix 2d.
5.21
The site
inspections and the document review procedures are mentioned in Section 8 of
this manual, the ET Leader shall pay special attention to the issues relating
to waste management, and check whether the Contractor has followed the recommended
mitigation measures and the relevant legislation and guidelines.