HONG KONG LEGISLATIVE COUNCIL — 1 June 1988
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levelled and there has been a slight increase in those detected. Fewer reports have been made to NPO but more have been made to patrolling officers. Since 1984 slightly more arrests have been made by members of the public.
There are no plans to revise the NPO scheme although it is intended that it should expand to keep pace with the needs of the community.
Environmental and ecological impacts of landfill sites
10. MR. LAU WONG-FAT asked: In view of the extensive coverage of the controlled tip to be set up in the western New Territories, which will be one of the largest of its kind in the world, will Government inform this Council what specific measures are now being taken to minimise the environmental and ecological impact caused by controlled tips on their surrounding areas and the residents there? In particular, as refuse trucks will inevitably pass through residential areas as they travel to and from the controlled tips, will Government also inform this Council whether an anti-pollution code of practice will be introduced to govern such undertakings and whether more advanced and better equipped transport facilities will be used?
SECRETARY FOR HEALTH AND WELFARE: Sir, Hong Kong's long-term strategy for waste disposal includes the establishment of three regional landfills in the west (WENT), north-east (NENT) and south-east (SENT) New Territories, which will be among the largest and most technically advanced of their kind in the world.
In common with all major public works projects, preliminary environmental reviews were carried out on both WENT and NENT before any commitment was made to detailed feasibility studies. Subsequently, rigorous environmental impact assessments were undertaken to define development and operation strategies which meet environmental criteria. The major environmental con- cerns of landfill projects are the containment, treatment and disposal of leachates, the control of gas emissions and noise nuisance.
A well engineered leachate containment system will be provided at WENT, comprising an impermeable liner and drainage layers on both sides of the liner. This system will prevent leachate from seeping through to the groundwater and into Deep Bay. The leachate thus collected will eventually be pumped to the north-west New Territories submarine outfall for disposal into the Urmston Road. In the interim, before this project is commissioned, the leachate will be transferred to the pillar point sewage treatment works for disposal.
In order to avoid the odour problems and hazard of gas migration, a series of landfill gas collection wells will be provided to pump gas, initially for flaring and later for utilisation. In addition, the daily covering of refuse and the filling-in of