new landfills are installed with gas extraction systems, and old
landfills are being retrofitted. Monitoring is conducted at the
boundaries of the landfills to ensure landfill gas does not escape.
In 2003, an average 0.5 million m3 of landfill gas was
collected daily, 47 % of which was used to meet nearly all on-site
energy consumption. Electricity generators with a total capacity
of 6.4 MW have been installed at landfills. In 2003, the EPD was
preparing a programme to sell landfill gas from the North East New
Territories (NENT) Landfill to public utilities operators.
A construction waste recycling plant has been operating at the South
East New Territories (SENT) Landfill since 1995, to sort and recycle
construction waste for beneficial reuse and reduce the amount of
waste taking up landfill space. At present, the plant recycles about
22 500 tonnes of construction waste monthly, representing 15% of
the total construction waste intake at the landfill. The EPD proposed
a charging scheme in 2003 to increase recycling and recover the
costs of handling construction waste (see 5.2e Environmentally Sound
Waste Management and Facilities for details).
transfer stations (RTSs) reduce the environmental impact of transporting
waste to landfills. Small refuse collection vehicles (RCVs) deliver
waste to the RTSs where it is transferred into bulk waste containers
that are taken to landfills either by road or by sea. Each container
can accommodate three to five RCV-loads. In 2003, about 1 200 RCV
trips to landfills were eliminated each day.
Hong Kong has eight RTSs, located mostly in built-up areas. Ventilation
and odour removal systems have been installed to reduce dust and
odour from the exhaust air. The Island West RTS is located within
a man-made cavern under Mount Davis which not only reduces its visual
impact, but takes up less land space.
Waste Treatment Centre (CWTC)
CWTC has been operating on Tsing Yi Island since 1993. Stack gas
from the incineration system is scrubbed and a spray dry absorber,
activated carbon injection and fabric filter baghouses are used
to remove pollutants prior to release into the atmosphere. The gas
is monitored continuously to ensure complete combustion and removal
of air pollutants. In the event of any problem, waste feed to the
incinerator will be cut off automatically.
The ambient air around the CWTC is monitored twice yearly and a
measurement of dioxins is carried out monthly. The results are lower
than or comparable to levels observed in other large cities around
the world. All process residues, including incineration ash, are
chemically treated and confirmed by analysis to be stable before
being taken to the SENT landfill for final disposal.
friendly practices are encouraged by allowing the contractor to
keep revenue from the sale of materials recovered from waste. Oil
recovered from oily wastewater is blended and used by ocean-going
vessels as recovered fuel oil. Copper oxide recovered from waste
etchant generated by the electronics industry is sent to overseas
smelters to recover the copper. In 2003, 6 200 tonnes of oil and
510 tonnes of copper oxide were recovered by the CWTC.
EPD’s laboratories (for air, water sciences and microbiology)
are operated in a manner that minimises the impact on the environment.
The laboratories comply with the legal requirements and statutory
licence conditions. Regular maintenance and monitoring programmes
are in place to ensure full compliance. In 2003, routine monitoring
of effluent discharges and annual monitoring of emissions from fume
cupboards indicated full compliance.
Government introduced an Indoor Air Quality Certification Scheme
for Offices and Public Places in September 2003. Certification is
open to offices or public places which are served by mechanical
ventilation and air conditioning systems and met the indoor air
quality (IAQ) requirements specified in the scheme. The first premises
to receive an Excellent Class IAQ Certificate was the EPD's Indoor
Air Quality Information Centre. By the end of 2003, 4 other EPD
premises including Southorn Centre, Revenue Tower, Tsuen Wan Government
Offices and the Wanchai Environmental Resource Centre were awarded
with Good Class IAQ Certificates. The goal is to have all EPD premises
EPD Indoor Air Quality Information Centre is the first
premises awarded an Excellent Class IAQ Certificate.
sample of the Excellent Class Indoor Air Quality Certificate.
non-toxic dye is used to trace pollution sources, to minimise the
environmental impacts of investigations. Field samples are sent
to the laboratories for appropriate action. Safety guidelines are
issued to all field staff who are trained in the handling of hazardous