THE ENVIRONMENT
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Landfills
All municipal solid waste is currently deposited at three large modern strategic landfills in the New Territories, developed by specialist waste management contractors to high environmental standards.
Rapid development in Hong Kong over the past decade has contributed to the dramatic increase in the amount of construction and demolition waste requiring disposal. Some 28 500 tonnes of such waste were generated every day during 1997, enough to fill 4.5 Olympic swimming pools. Since much of the construction waste delivered to landfills could be reused, contractors are encouraged to segregate and sort their waste at source before disposal. About 6 500 tonnes out of the 28 500 tonnes were dumped at landfills every day. The rest was delivered to public filling areas for use in land reclamation.
Hong Kong has 13 old landfills, none of which has been properly restored. Landfill gas and liquid leachate, which are the products of natural decay of organic wastes, are continuously released and cause considerable impact on the environment. For safety and environmental reasons, these landfills are now being restored. Restoration work has already started on seven of these landfills and will be completed by late 1998. After full restoration, the sites may be used for community activities.
Refuse Transfer Stations
An important component of the government's waste disposal plan is the development of a network of refuse transfer stations. Waste collected in urban centres is delivered to these stations for compacting into sealed containers for subsequent delivery to and disposal at the three strategic landfills.
Five modern transfer stations handle a total of 4 500 tonnes of waste every day, from the 5.5 million population of Hong Kong Island, Kowloon, and most of the developed areas in the New Territories. This is mostly domestic waste, and represents about 70 per cent of Hong Kong's total daily domestic waste production. Construction of new stations on North Lantau and the Outlying Islands are in progress and a tender will be invited shortly for the provision of a station to serve the north-west New Territories.
Chemical and Special Wastes
Each day some 180 tonnes of chemical waste and MARPOL waste are collected from 9 200 waste producers and sea-going vessels calling at the port of Hong Kong are treated at a Chemical Waste Treatment Centre on Tsing Yi Island. This centre, the main treatment facility for chemical waste, is operated by a government contractor, recovering part of its running costs through a user direct-charging scheme. Waste producers are encouraged to adopt clean technologies to minimise their wastes and so to cut their treatment costs. Most of Hong Kong's chemical waste is treated at the centre but some solid chemical waste, such as asbestos, is sent to landfills.
To help farmers dispose of their livestock waste properly, a door-to-door livestock waste collection service commenced in July 1996. A monthly average of 1 530 tonnes of livestock waste was collected during the year and sent to Sha Ling Composting Plant for composting.