ENG-1991 — Page 422

THE ENVIRONMENT

Before the implementation of the forthcoming chemical waste control regulations, a permit system is being adopted for regulating the disposal of chemical waste with municipal wastes at the Tseung Kwan O and Pillar Point Valley landfills. Spent chemicals from industrial processes and asbestos waste from building demolition and refurbishment were the major waste types disposed of during 1991. A new screening procedure was introduced at the Tseung Kwan O waste reception laboratory to check that the wastes delivered to the landfill matched the description in the permits. This system ensures a higher standard of safety compliance and will detect the delivery of forbidden wastes. The Asbestos Waste Action Plan introduced in 1990 continued to be an effective means of ensuring that safety guidelines in the Code of Practice on asbestos waste are followed by waste producers and disposal contractors, as substantiated by the great reduction in malpractices during 1991.

An initial study has been completed on the interim and long-term arrangements for the disposal of waterworks and sewage sludges. Several options including sea and land disposal as well as incineration have been examined. Further investigations were initiated to assess the acceptability and reliability of the various options.

In view of the current unsatisfactory disposal arrangement for clinical waste, animal carcasses and security waste, a study has been initiated on the development of a centralised incineration facility for such wastes. It is planned to have a facility in operation by 1994–5.

Monitoring and Investigations

Water Quality

The Environmental Protection Department is responsible for water quality monitoring in the sea, at beaches, and in rivers and streams. It operates a comprehensive monitoring programme which involves 88 general marine monitoring stations, 72 seabed sediment stations, 23 typhoon shelter stations, 118 sampling points at beaches, and 87 manual and 6 automatic sampling points on 10 priority rivers. The results are used to detect water pollution problems and to assess the water quality against a series of quality objectives.

Generally, water quality is good in Hong Kong's open marine waters. However, pollution problems, exemplified in the form of either oxygen depletion, high bacterial counts or algal blooms, exist in some parts of Victoria Harbour (Kowloon Bay, North-west Kowloon and Rambler Channel near Tsuen Wan), the inner parts of embayments (Tolo Harbour, Port Shelter, Junk Bay and Deep Bay) and typhoon shelters. Trends of water quality deterioration have been found in some of these blackspots, in particular Victoria Harbour and Tolo Harbour.

The monitoring results show that many rivers and streams are heavily contaminated with livestock waste, sewage and industrial effluents. In some cases, high bacteria numbers in the river estuaries cause concern. Yet, during the year, slight improvements were detected in some watercourses such as Lam Tsuen, Tai Po, Fo Tan, and Shing Mun rivers, mainly as a result of the implementation of the WPCO in the Water Control Zones, livestock waste control, clearance of squatter areas and the interception of sewage from villages.

Until recently, the bacteriological water quality at many of Hong Kong's beaches had been declining for a number of years. The deterioration was caused mainly by livestock. waste and raw or partially-treated sewage entering the sea at or close to the beaches. The increasingly-large number of faecal bacteria in these discharges contaminated the water at many beaches, posing a health risk to swimmers.

361