5.1.1
Waste management would be the
contractor’s responsibility to ensure that all wastes produced during the
construction phase for the drainage improvement works are handled, stored and
disposed of in accordance with good waste management practices and EPD’s
regulations and requirements.
5.1.2
Waste materials generated during
construction activities, such as construction and demolition (C&D)
material, chemical wastes and general refuse, are recommended to be audited at
regular intervals (at least quarterly) to ensure that proper storage,
transportation and disposal practices are being implemented. The Contractor
would be responsible for the implementation of any mitigation measures to
minimise waste or redress problems arising from the waste materials.
5.2.1
Mitigation measures for waste
management are summarised below. With the appropriate handling, storage and
removal of waste arisings during the construction works as defined below, the
potential to cause adverse environmental impacts would be minimised. The
implementation schedule of the recommended mitigation measures is presented in Appendix
A. During the site inspections, the ET should pay special attention to the
issues relating to waste management and check whether the Contractor has
implemented the recommended good site practices and other mitigation measures.
Good Site Practices
5.2.2
Appropriate waste handling,
transportation and disposal methods for all waste arisings generated during the
construction works should be implemented to ensure that construction wastes do
not enter the river and stream channels, and that no waste, spoil and/or excavated materials
will be dumped/stockpiled in the adjacent ecological habitats such as marsh,
agricultural land, woodland, shrubland, plantation area and fishpond.
5.2.3
It is expected that adverse impacts
from waste management would not arise, provided that good site practices are
strictly followed. Recommendations for
good site practices during construction include:
·
nomination of approved personnel, such as a site
manager, to be responsible for good site practices, and making arrangements for
collection of all wastes generated at the site and effective disposal to an
appropriate facility;
·
training of site personnel in proper waste management
and chemical waste 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;
·
regular cleaning and maintenance programme for drainage
systems, sumps and oil interceptors;
·
a recording system for the amount of wastes generated,
recycled and disposed (including the disposal sites) should be proposed; and
·
a Waste Management Plan should be prepared and
submitted to the Engineer for approval.
One may make reference to ETWB TCW No. 15/2003 for details.
5.2.4
In order to monitor the disposal of
C&D material at landfills and public filling areas, as appropriate, and to
control fly tipping, a trip-ticket system should be included as one of the
contractual requirements to be implemented by an Environmental Team undertaking
the Environmental Monitoring and Audit work.
One may make reference to WBTC No. 21/2002 for details.
Waste Reduction Measures
5.2.5
Good management and control can
prevent the generation of significant amounts 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;
·
separate labelled bins should be provided to segregate
aluminium cans from other general refuse generated by the workforce, and to
encourage collection of by individual collectors;
·
any unused chemicals or those with remaining functional
capacity should be recycled;
·
maximising the use of reusable steel 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 should 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;
·
plan and stock construction materials carefully to
minimise amount of waste generated and avoid unnecessary generation of waste;
and
·
minimize over ordering of concrete, mortars and cement
grout by doing careful check before ordering.
5.2.6
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.
Construction and Demolition Material
5.2.8
When disposing C&D material at a
public filling area, it should be noted that the material should only consist
of soil, rock, concrete, brick, cement plaster/mortar, inert building debris,
aggregates and asphalt. The material
should be free from marine mud, household refuse, plastic, metals, industrial
and chemical waste, animal and vegetable matter, and other material considered
to be unsuitable by the Filling Supervisor.
5.2.9
The C&D material generated from
demolition of existing structures and river crossings should be sorted on-site
into inert C&D material (that is, public fill) and C&D waste. Suitable areas should be designated within
the works site boundaries for temporary stockpiling of C&D material. Within stockpile areas, the following
measures should be taken to control potential environmental impacts or
nuisance:
·
covering material during heavy rainfall;
·
locating stockpiles to minimize potential visual
impacts; and
·
minimizing land intake of stockpile areas as far as
possible.
Excavated Riverbed Material
5.2.10
It is anticipated that the excavated
riverbed material may need to be temporarily stockpiled on-site prior to
disposal off-site. Details of
environmental control measures to be taken at the stockpiling area to prevent
water pollution are discussed in Section 5.
Use of water-tight trucks would be required for the transportation of
excavated riverbed material to the designated barging point for disposal at the
designated public filling area, or transported directly to the public filling
area.
Chemical Wastes
5.2.11
If chemical wastes are produced at the
construction site, the Contractor would 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 explosives, flammable, oxidizing, irritant, toxic,
harmful, corrosive, etc. The Contractor
should use a licensed collector to transport and dispose of the chemical wastes
generated at the Chemical Waste Treatment Centre at Tsing Yi, or other licenced
facility, in accordance with the Waste Disposal (Chemical Waste) (General)
Regulation.
General Refuse
5.2.12
General refuse should be stored in
enclosed bins or compaction units separate from C&D material. A reputable
waste collector should be employed by the contractor to remove general refuse
from the site, separately from C&D material. An enclosed and covered area
is preferred to reduce the occurrence of 'wind blown' light material.