ENG-1991 — Page 420

THE ENVIRONMENT

Disposal and Treatment Facilities

The construction work for the Shau Kei Wan screening plant and outfall and the To Kwa Wan screening plant and outfall was substantially completed, while that for the North West Kowloon sewage treatment and disposal project is expected to be completed by late 1992.

Design work was substantially completed for the East Kowloon pollution control and sewerage improvement project, which provides a major relief sewer for the whole area, a dry weather flow interception for major stormwater drains, and a pumping main from Yau Tong to the Kwun Tong screening plant. The scheme will improve water quality in the Kai Tak Nullah and Kowloon Bay typhoon shelter.

Under the Hong Kong Island South sewerage improvement project, construction work commenced on the underground sewage treatment works for Stanley. The design work for a screening plant at Shek O and various sewage pumping stations and sewerage systems in the area continued to progress. The project will improve water quality along the south coast of Hong Kong Island, particularly adjacent to Repulse Bay, Shek O and Stanley main beaches.

During 1991, modification of the sewage treatment processes at Tai Po and Sha Tin to reduce the amount of nitrogen discharged into the semi-landlocked Tolo Harbour was completed. Another important element of the plan to reduce the amount of pollution going into Tolo Harbour is the Effluent Export Scheme. Works for this scheme are ongoing and scheduled to be completed in 1994. On completion, treated effluent from the Tai Po and Sha Tin sewage treatment works will be removed entirely from the Tolo catchment via a partially-tunnelled system of sewers, and discharged to the Kai Tak Nullah. Apart from reducing the nutrient loads on Tolo, this will have the added benefit of diluting the organic pollution in Kai Tak Nullah and Kowloon Bay typhoon shelter.

Under the Marine Disposal of Sludges Scheme, 1991 saw the start of a five-year trial period during which treated sludges from the drinking water purification and sewage treatment processes at Sha Tin are disposed of at sea. The sludges are transported to a carefully selected site near Waglan Island in a specially-designed sludge disposal vessel. Environmental monitoring at the dumping area commenced at the same time to ensure that the impact is within acceptable limits.

Landfills

The bulk of municipal solid waste is currently disposed of at three landfills, at Tseung Kwan O, Shuen Wan and Pillar Point Valley. As part of the territorial waste disposal strategy, three large-capacity landfills are being developed in remote parts of the New Territories to provide the necessary capacity for disposal of waste for the next 20 years. These landfills will be served by a network of refuse transfer stations which will transfer the waste from small refuse collection vehicles to bulk containers, reducing cost and environmental problems. The strategic landfills will be designed, constructed and operated to the highest standards by experienced waste management contractors.

Construction of the access roads to the West New Territories Landfill and North-east New Territories Landfill commenced in 1989 and 1991 respectively. Tenders for the design, construction and operation of the former were sought from a list of pre-qualified international waste management contractors, and actions were put in hand for similar exercises for the North-east and the South-east New Territories Landfills in 1992.

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