LAND, PUBLIC WORKS AND UTILITIES
non-destructive engineering geophysical techniques for site characterisation. Research into the nature and occurrence of landslides on natural terrain was also carried out, and an inventory of such landslides was completed and made available for public reference.
The GEO's Geotechnical Information Unit (GIU) in the Civil Engineering Library houses the largest collection of geotechnical data in Hong Kong. It is open to the public and served more than 30 000 users during 1997.
The GEO manages the Public Works Central Laboratory at Kowloon Bay and six Public Works Regional Laboratories in various parts of Hong Kong. These laboratories are accredited under the Hong Kong Laboratory Accreditation Scheme (HOKLAS) to carry out specific tests on construction materials and to provide laboratory calibration services. More than 296 tests were carried out in 1997.
The GEO provides ground investigation services for government projects. In 1997, major ground investigations were carried out for the proposed Route 16 from West Kowloon to Sha Tin, Tseung Kwan O Development, South Cheung Chau disposal area and water supply to Tan Kwai Tsuen North, Yuen Long. Many ground investigations were completed for the accelerated LPM Programme.
In 1997, the GEO provided geotechnical advisory services to government departments on a wide range of projects including road improvement works, such as the Tsing Yi North Coastal Road project, construction of embankments on soft clay for the Shenzhen River Regulatory Works, drainage improvement works in Yuen Long, and site formation and slope works for various other projects.
Fill Supply and Mud Disposal
The Fill Management Committee (FMC), formed in 1989, is responsible for identifying, investigating and managing fill resources and marine disposal areas required for developments in the HKSAR. Technical and administrative support for the FMC is provided by the FMC Secretariat, which is housed in the GEO of the Civil Engineering Department (CED).
From 1990 to 1997, about 260 million cubic metres of marine fill (15 per cent from nearby regions in China) and 160 million cubic metres of land-based fill were used for reclamation projects. It is expected that a further 400 million cubic metres of fill will be required to meet the need for land for housing and infrastructure developments in Hong Kong over the next 10 years.
The CED managed the mud disposal facilities. During the year, about 12 million cubic metres of uncontaminated mud generated from various projects were disposed of in open sea floor disposal grounds and in exhausted marine sand borrow pits; about 13 million cubic metres of contaminated mud were placed in the purpose- dredged seabed pits at East Sha Chau. An empty marine sand borrow pit in East Sha Chau for contained disposal of contaminated mud came into operation in late-1997. The Public Filling Sub-Committee of the FMC co-ordinated the public filling activities for beneficial use of construction and demolition debris. During the year, about 4.4 million cubic metres of pubic fill were used in reclamations.
In connection with the management of Hong Kong's fill resources and mud disposal capacity, the CED, on behalf of the FMC, continued to undertake a series of geotechnical, environmental and ecological studies to examine the effects of the
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