THE ENVIRONMENT
into operation in March 1995. Waste producers are encouraged to adopt clean production technologies and to minimise their wastes so as to reduce treatment costs. All chemical waste producers must properly store and dispose of their chemical waste. A trip ticket system involving the waste producers, licensed collectors and licensed disposal points tracks the movement of chemical waste from the point of origin to the point of final disposal. Most of the chemical waste goes to the treatment centre but some, such as asbestos, is sent to landfills for disposal.
The asbestos waste action plan, introduced in 1990, has been replaced by statutory control under the Waste Disposal (Chemical Waste) (General) Regulation, ensuring that waste producers and disposal contractors follow safety guidelines on asbestos
waste.
`Under a five-year trial, treated sludge from the waterworks and sewage treatment works at Sha Tin is disposed of at sea some 15 kilometres east of Waglan Island. About 40 000 cubic metres of sludge are dispersed every month at the disposal ground, which was selected after detailed study. Monitoring of the water, marine sediment quality and biotic community at the spoil ground is continuing, to assess any impact on the environment. The data analysed in 1995 showed no clear evidence of ecological damage but changes at the dumping site were detected and it was decided to make plans to halt the dumping. The intention is to dewater the sludges and dispose of them at landfills. This should start in mid-1996. Monitoring will, however, continue so as to complete the assessment of any impact on the environment.
A centralised incineration facility is planned for the disposal of clinical waste, animal carcasses and some security wastes.
A government-appointed contractor collects livestock waste that would otherwise be dumped into streams and rivers in the New Territories. In 1995, some 1 200 tonnes of solid waste were collected and sent to the government-operated composting plant at Sha Ling for recycling.
Monitoring and Investigations
The assessment of progress towards policy goals is one of the key activities of the EPD. Its routine monitoring and special investigations form the basis for all the strategic planning, provision of facilities and statutory controls aimed at improving the environment. The EPD has more than 100 sampling stations in the open sea, enclosed bays and typhoon shelters; plus another 80-odd stations for inland waters. It also keeps 42 gazetted bathing beaches under surveillance. This monitoring goes back to 1972 and provides a comprehensive record of the chemical, physical and microbiological quality of Hong Kong's waters.
All the data are published regularly and can be made available to scientists and engineers on computer disks or tapes. Members of the public are usually more interested in the summary reports of bathing water quality which are issued to the media and published in newspapers every two weeks during the summer.
Mathematical models are frequently used to assess the water quality impact of major development activities in Hong Kong. With increasing collaboration between Hong Kong and local authorities in mainland China, mathematical modelling is also becoming a useful tool for evaluation of cross-border development projects.
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