THE ENVIRONMENT
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Kowloon, and insistence on the use of quieter aircraft. This noise problem will be satisfactorily resolved when the airport is relocated.
Construction and Demolition
Operation of powered mechanical equipment for general construction work between 7 p.m. and 7 a.m., and on public holidays, is controlled through a Construction Noise Permit system. The permits restrict the use of equipment in accordance with stringent noise criteria. From November 1996, the control became more stringent in populated areas for certain particularly noisy equipment. In addition, noisy manual activities also came under control in built-up areas. Percussive piling work requires a permit even during the daytime and is prohibited during the restricted hours. Noisy piling machines may be operated up to only three hours a day in urban areas but quieter ones can work up to 12 hours. In 1996, some 3 200 permits were issued. There were about 120 convictions for work without permits or violating permit conditions.
Noise emission from hand-held percussive breakers and air compressors for construction activities is controlled. Only those complying with stringent noise. emission standards can obtain a 'green' Noise Emission Label and allowed to be used. In 1996, about 1 700 labels were issued and there were 13 prosecutions for operating these types of equipment without a label.
Control of asbestos is a concern in demolition of buildings. The Air Pollution Control Ordinance controls environmental asbestos by requiring engagement of registered asbestos consultants, contractors, supervisors and laboratories in asbestos- related activities, and submission of asbestos investigation reports and asbestos- abatement plans to the EPD before asbestos removal works start. Also, the import and sale of both amosite and crocidolite asbestos were banned from May 1996.
During 1996, EPD made 480 inspections, mainly of building demolition and renovation sites, to ensure materials containing asbestos were handled and disposed of properly in accordance with relevant guidelines and codes of practice. Its asbestos laboratory analysed 220 bulk samples and 105 air samples.
The large number of port- and airport-related projects has generated a vast quantity of dredged marine spoil that is unsuitable for reclamation. The dredged marine spoil is dumped at sea at specified spoil grounds. These marine dumping activities are subject to permit control by the Director of Environmental Protection under the Dumping at Sea Ordinance. The department does not permit marine dumping of surplus excavated material and other construction wastes unless there is no land-based disposal option and the marine dumping of the waste has no undue adverse impact.
Because of the serious impact of illegal dumping on the marine ecology, the department maintains strict control. A vessel must be equipped with an automatic self-monitoring device before it can be listed in the marine dumping permit. The device tracks all marine dumping operations by keeping a record of the position and draft of the vessel, so that the authorities can trace any illegal dumping in a cost- effective manner. The EPD's inspectors operate frequent patrols, offenders are prosecuted, and repeat offenders face having their permits revoked or applications for new ones refused.