THE ENVIRONMENT
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An advanced network of six continuous air quality monitoring stations has been established to evaluate air pollution levels in urban areas and provide data for the government's environmental planning and control programmes. In line with the declara- tion of air control zones and air quality objectives throughout Hong Kong, a progressive expansion of network coverage into new town and rural areas of the territory will be required in the future. Development of vehicular pollution monitoring stations has also continued.
During the year, a revolutionary new data telemetry system, designed by Environmental Protection Department staff, began operation. This system enables pollution measurements from any of the urban monitoring stations to be continuously relayed by telephone line to a computerised network control centre. In 1986, over 25 million pollution measurements were taken, processed and analysed in this way.
Results from the air pollution monitoring network during 1986 demonstrate that levels of sulphur and nitrogen oxides emitted as a result of fuel combustion from stationary sources and motor vehicles, are generally low in urban areas of Hong Kong. However, considerably higher levels of these pollutants are present in industrial areas such as Kwun Tong or Kwai Chung. In particular, a marked upward trend in nitrogen dioxide levels was observed during 1986. Levels of total and respirable particulates also remained relatively high at all monitoring stations, notably during the dry winter months. High levels of rainfall acidity and heavy sulphate deposition rates in rain were also measured at a number of locations during the year. Intensive investigations into ‘acid rain' are continuing.
A number of additional air quality investigations was undertaken in 1986. The mobile air quality monitoring laboratory was deployed for short periods in a number of areas not covered by the present network of permanent monitoring stations. This laboratory was used for an intensive study of air quality in the Deep Bay area adjoining Hong Kong and China. This project was carried out jointly with the Guangdong Environmental Protection Bureau. Investigations of photochemical pollution have also been made with this labora- tory, as well as by using specially equipped aircraft of the Royal Hong Kong Auxiliary Air Force. In general, these studies have shown higher levels of photochemical oxidants in rural rather than urban areas.
One of the water quality investigations initiated in 1986 was a three-year study to be conducted jointly by the EPD and the Department of Community Medicine at the University of Hong Kong, to evaluate any possible link between water quality and the health of bathers at gazetted beaches.
Investigations of polluting discharges are carried out throughout the territory in response to complaints and to track down the sources of pollution discovered through routine monitoring. During the past year much of this activity has been directed at identifying discharges of industrial and other effluents into surface water drains and in many cases action has been taken against factory owners requiring them to install and use appropriate drainage facilities.
Waste arisings are now monitored annually and the information is used to plan future waste disposal facilities. In 1986, waste quantities increased by 16 per cent from 6900 tonnes a day in 1985 to 8 000 tonnes a day. This represented an increase of six per cent collected by the Urban Services and Regional Services departments, an increase of 11 per cent collected by the private sector and 55 per cent increase in construction waste.
Measurements of beta and gamma radioactivity in airborne dust and rainwater are made by the Royal Observatory at King's Park. The observatory cooperates with the United Kingdom Atomic Energy Research Establishment and the International Atomic Energy