ENG-1993 — Page 443

THE ENVIRONMENT

Hong Kong's objectives for air quality are comparable to internationally-recognised air quality standards for the protection of public health. The actual air quality does not always meet the objectives. Total suspended particulates, respirable suspended particulates and nitrogen dioxide are often high. In 1993, the highest annual averages recorded were 320 micrograms per cubic metre of total suspended particulates and 180 micrograms per cubic metre of respirable suspended particulates, both at levels above the objectives. Nitrogen dioxide was near its objective of 80 micrograms per cubic metre. Emissions from motor vehicles are the main source of these pollutants, and preparatory work for the introduction of cleaner automobile fuel and tighter standards for heavy duty diesel vehicles was undertaken. A scheme to largely replace the use of light duty diesel with unleaded petrol is being formulated.

The ever-increasing demand for transport has led to serious noise problems in areas close to major roads and rail transport corridors. The continued re-paving of roads with quieter surfaces and noise-insulating of schools brought further relief to more Hong Kong residents. The Kowloon-Canton Railway Corporation embarked on a massive 10-year programme to abate the noise along its entire railway line through the use of noise barriers and enclosures. The Mass Transit Railway Corporation also started to implement a noise mitigation programme for its rolling stock, railway tracks and maintenance depots.

Urban sewerage grew alongside the city without an overall controlling strategy. The Environmental Protection Department has estimated that, due to the many expedient connections between foul sewerage and storm drains, only half the city's sewage million tonnes a day gets any treatment before it flows into the sea. The resulting load of water pollution has a severe impact on confined areas such as typhoon shelters. In the worst of these, such as the Kowloon Bay typhoon shelter beside Kai Tak airport, foul-smelling and toxic gases stem from the polluted water. A major $500 million re-sewerage project is under construction under Stage I of the East Kowloon sewerage master plan to bring substantial relief to the area by late 1994.

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In the harbour, water quality does not reach desired standards. The median concen- tration of dissolved oxygen, a good indicator of water quality, is close to 50 per cent saturation the minimum level the water quality objectives allow. Phase I of the strategic sewage disposal scheme, for which detailed investigations and design are in progress, will reduce harbour pollution significantly. The declaration of two more water control zones (the Western Buffer and Eastern Buffer Water Control Zones) in 1993 will also reduce pollution in the harbour through the enforcement of the Water Pollution Control Ordinance.

With the community's growing expectations for a better environment, the need for a cost-effective, secure and environmentally acceptable waste management programme has been recognised.

Consideration is also being given to the control of special categories of waste, such as clinical waste, decomposing carcasses and various types of sludge.

The comprehensive control of the handling and disposal of chemical waste commenced in May with the opening of the chemical waste treatment centre and full implementation of the Waste Disposal (Chemical Waste) (General) Regulation. Hong Kong is now able to stop the widespread malpractice of dumping untreated chemical waste into the territory's sewers and surface waters, in this way improving the water quality in the receiving waters, particularly the inner harbour.

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