LAND, PUBLIC WORKS AND UTILITIES
Hong Kong consumed 12.5 million tonnes of aggregates and other rock products in 2002. About 40 per cent of its demand for aggregates and rock products was met locally, with the balance imported from the Mainland.
In 2002, one quarrying contract and three quarry rehabilitation contracts were in force. The rehabilitation contracts require the operators to rehabilitate the quarries within a specified period, in return for the granting of rights to process and sell surplus rock excavated during the course of the works. The rehabilitation works involve recontouring and extensive planting to blend the quarries with the surrounding hillsides.
The CED manages two government explosives depots (one on Lantau Island and the other at Piper's Hill, Sha Tin) which provide bulk storage facilities for imported explosives. It also undertakes the delivery of explosives from the depots to blasting sites and issues shotfirer certificates.
The largest use of explosives during the year was for quarrying and site formation works. The overall consumption of explosives was 1 900 tonnes.
The department also provides technical support to the Home Affairs Bureau and the Marine Department in assessing applications for fireworks displays.
Fill Supply and Mud Disposal
The Marine Fill Committee (MFC) is responsible for identifying and managing the supply of marine fill resources for development projects, and for managing disposal facilities for dredged sediments. The Public Fill Committee (PFC) has the duty to manage construction and demolition (C&D) materials and utilisation of land-based fill reserves. Both committees are responsible to the Secretary for the Environment, Transport and Works.
In 2002, the amount of marine sand used for reclamation projects has been reduced from 66 million cubic metres in 2001 to about 32 million cubic metres; and about 22 million cubic metres of it were imported from nearby regions in the Mainland. To reduce future use of marine sand and help preserve its limited resources in Hong Kong, more use will be made of inert C&D materials as fill for reclamation.
About 9.1 million cubic metres of C&D materials were generated by local construction activities in 2002. Of this, about 6.6 million cubic metres of inert materials were re-used as fill in public filling areas including Tseung Kwan O Area 137, Pak Shek Kok, Tuen Mun Area 38, North Tsing Yi and Penny's Bay.
The PFC continues to explore ways to minimise the generation of C&D materials and reduce their disposal at landfills. The construction industry is encouraged to adopt construction methods and materials that reduce the generation of C&D materials at source. A temporary recycling facility at Tuen Mun Area 38 has started to operate for recycling of suitable C&D materials into aggregates for re-use.
The MFC maintains a Fill Management Database on fill requirements, mud disposal and surplus excavated materials from major public and private projects. Its purpose is to help the construction industry coordinate sources of fill materials and make the best use of surplus materials. All project data is available on the Internet. The CED manages mud disposal facilities. In 2002, about 11 million cubic metres of uncontaminated mud and three million cubic metres of contaminated mud were generated from various works projects. Uncontaminated mud was disposed of at open sea floor disposal grounds or exhausted marine sand borrow pits. Contaminated mud
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