ENG-1992 — Page 437

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THE ENVIRONMENT

Construction of the second transfer station at Island East was completed in November 1992. Collected refuse is compacted into sealed containers and then delivered to landfill sites by purpose built vessels. After the commissioning of this transfer station, the incinerator at Kennedy Town will be phased out in early 1993 to improve air quality in the vicinity.

Tenders for the third refuse transfer station at Sha Tin were invited from pre-qualified experienced waste management contractors in 1992. The station is expected to be operational in 1994.

A study into the feasibility of building an underground transfer station inside a rock cavern site on the western side of Hong Kong Island was commissioned in 1992. Detailed planning of this underground transfer station is in progress and tenders will be invited in 1993. Consultancy studies for refuse transfer station projects for the outlying islands, Yuen Long and West Kowloon commenced in 1992, with target commissioning dates in 1995 and 1996.

Chemical and special wastes

There were until recently no central treatment facilities for chemical wastes in Hong Kong and there were practical, technological and financial obstacles to local industries having their own. This led the government, in December 1990, to appoint a specialist contractor to design, build and operate a chemical waste treatment centre on Tsing Yi Island.

The centre is the first integrated facility for chemical waste in the region. It was completed in late 1992, and will be fully commissioned in early 1993. It provides collection, transport, treatment and final disposal of chemical waste, helping the waste producers to comply with the law.

The Chemical Waste Treatment Centre serves also as the regional reception point for oily and noxious liquid wastes from ships. This meets Hong Kong's obligations under the International Convention for the Prevention of Pollution from Ships and its Protocol (the Marpol Convention).

Until the full legislative controls come into force, a permit system regulates the disposal of chemical waste at the Tseung Kwan O and Pillar Point Valley landfills. A screening procedure at the Tseung Kwan O waste reception laboratory checks that the wastes delivered to the landfill match the description in the permits. This system ensures a high standard of safety and will detect the delivery of unacceptable wastes.

The asbestos waste action plan, introduced in 1990, continued to be an effective means of ensuring that waste producers and disposal contractors follow safety guidelines in the code of practice on asbestos waste.

With the implementation of legislative control, the permit system is being replaced by new statutory requirements. Most of the chemical wastes are diverted to the chemical waste treatment centre for proper treatment before final disposal.

All chemical wastes and treated residue delivered to the landfill for disposal are chemically analysed in a standard screening procedure. This system will ensure proper 'cradle to grave' tracking and control on all chemical wastes.

In a five year trial, treated sludges from the waterworks and sewage treatment processes at Sha Tin are disposed of at sea near Waglan Island, using a purpose-built vessel. Approximately 40 000 cubic metres of sludge is disposed of every month at the spoil ground, which has been selected after detailed environmental monitoring. Monitoring of the water and marine sediment quality at the spoil ground is continuing in order to provide an early indication of any adverse effects on the environment.