ENG-1987 — Page 349

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THE ENVIRONMENT

graphs were installed at two locations with different soil properties. On average about 150 earthquakes were detected annually with epicentres within 320 kilometres of Hong Kong; more than four of these were felt by residents in Hong Kong.

The observatory operated a caesium beam atomic clock which provided time signals accurate to fractions of a microsecond a day. A six-pip signal was broadcast on 95 MHz every quarter hour and was also relayed to Radio Television Hong Kong for broadcast to the public.

Background Radiation Monitoring

As part of an international network, the Royal Observatory has been monitoring atmospheric radioactivity since 1960 to determine the global air transport of radioactive dust and other contaminants. In response to the public's concern over the possible environmental effects of the Daya Bay Nuclear Power Station about 50 kilometres to the northeast of Hong Kong, the Royal Observatory's monitoring activity has been expanded into a Background Radiation Monitoring Programme. The programme aimed at establish- ing an accurate baseline of the background radiation levels in Hong Kong prior to the commissioning of the nuclear power plant. In addition to the Central Radiation Labora- tory at King's Park, three atmospheric sampling stations were set up at Yuen Ng Fan, Tsim Bei Tsui and Sha Tau Kok to sample atmospheric particulates and deposition as well as to monitor the direct gamma-radiation levels using high-pressure ionisation chambers. With the installation of the high-purity germanium detector system and the liquid scintillation counting system, extensive gamma and beta measurements of samples of air, water, soil and foodstuffs were carried out in 1987.

Protecting the Environment

The development of Hong Kong as one of the world's greatest ports as well as a major manufacturing centre has not been without its price in terms of damage to the environment. Increasingly, there is a demand for this damage to be reduced and even reversed.

A great deal of effort and money is now being expended to ensure that polluting activities such as intensive livestock farming and some manufacturing industries can continue in ways that are less damaging to the environment and less threatening to the health of the community. Aspects that have given rise to particular public concern during the year, or are considered by the government to need special attention, include:

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the continued severe pollution of the New Territories by livestock wastes

- pollution at bathing beaches

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water pollution blackspots such as nullahs and typhoon shelters

smoke emissions from diesel-engine vehicles, which constitute about 68 per cent of the total vehicle distance travelled on the road

the general level of particulates in the atmosphere

the control of health hazards relating to the use and removal of materials containing asbestos in buildings, and

the continuing need to control and dispose of the large amounts of sewage, municipal, chemical and other wastes generated by the community.

For the future, the continued vitality of topographically confined air and water sys- tems, such as those of Deep Bay, Tolo Harbour, Junk Bay, Port Shelter and Victoria Harbour, is at risk. These systems are subject to new or additional pressures as a result of urbanisation which often involves entire new towns for several hundred thou- sand people.