THE ENVIRONMENT
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Wastes
Waste arisings are monitored annually and the information is used to plan future waste disposal facilities. Compared to the 1988 arisings, waste quantities remained steady in 1989 at 13 000 tonnes per day. The quantities of domestic waste and industrial/commercial wastes increased by five per cent and four per cent respectively, while construction waste decreased by 10 per cent. This reflects the continued growth in the industrial/commercial activities and the decline of construction activities in the year.
The export of waste materials for recycling also showed an increase from 1.15 million tonnes per day in 1988 to 1.22 million tonnes per day in 1989, which is equivalent to 21 per cent of the total municipal waste. This export_activity brought about an economic contribution of 2.45 billion dollars.
Air Quality
The EPD operates a comprehensive air monitoring programme throughout the territory. During 1989, the department increased the number of continuous monitoring stations to eight in order to acquire air quality data for planning and control purposes.
The department has further plans to expand the monitoring network to cover the entire territory. Work has started on a full-scale permanent station in Aberdeen to obtain air quality data for the Hong Kong South area. New monitoring stations in Sha Tin and Tai Po are under development. All continuous air quality measurements made at the remote stations are telemetered to the EPD's central computer for processing and reporting.
In order to facilitate the enforcement of the Air Pollution Control Regulations on specified processes, the EPD procured a mobile Stack Emission Monitoring Laboratory at the end of 1989. This laboratory is deployed in monitoring stack emissions for checking compliance with the licensing conditions for specified processes.
Ambient sulphur dioxide concentrations in the atmosphere in most industrial areas in 1989 exceeded the Air Quality Objectives (AQOs). Particularly bad areas were Kwun Tong and Kwai Chung. As for nitrogen dioxide, ambient levels were similar to those of 1988 and on a few occasions, the short-term nitrogen dioxide objectives at Kwun Tong stations were exceeded. High levels of both total and respirable suspended particulates were also measured at all monitoring stations, all exceeding the annual AQOs. Hong Kong is not without its problems with acid rain, as high levels of rainwater acidity were recorded on several occasions, and a comparatively high sulphate deposition rate in rain was recorded in industrial areas at Kwun Tong and Kwai Chung monitoring stations. Levels of photochemical oxidant remained low throughout the year.
In a study of the air quality in road tunnels, the levels of carbon monoxide, nitrogen dioxide, nitric oxide, and other parameters indicated that the air quality in general met the criteria adopted overseas. However, odour as well as high temperatures and humidity in the tunnels have elicited some complaints. In view of this, the EPD has given advice to the Transport Department on ways of improving ventilation and air monitoring facilities inside the tunnels.
Noise Control
To facilitate enforcement of the Noise Control Ordinance, it is essential that noise measurement equipment and instruments are accurate and reliable. With this in mind, EPD has set up an Acoustic Testing Laboratory which is equipped with an advanced calibration system. This can provide accurate and reliable calibration services for the principal operations required for the enforcement of the ordinance.