THE ENVIRONMENT
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To monitor earthquakes and seismicity, three short-period seismometers are operated at Cheung Chau, High Island and Tsim Bei Tsui. Long-period seismographs at the obsvervatory record tremors from all over the world. Strong-motion accelerographs are operated at the observatory and Tate's Cairn which are two locations with different soil properties. About 140 earthquakes with epicentres within 320 kilometres of Hong Kong are detected annually. Reports of significant tremors are routinely made known to the general public via the mass media. Seismic data are used by structural engineers in the design of buildings. Such data are also made available to local and overseas scientific institutions for their studies.
The Hong Kong Time Standard is provided by a caesium beam atomic clock at the Royal Observatory headquarters and accuracy of fractions of a microsecond a day is maintained. The time service is operated by means of the relay of a six-pip time signal to Radio Television Hong Kong for transmission.
Environmental Problems
Industrial, commercial and domestic activities in Hong Kong produce a wide variety of wastes of varying quantities. These wastes lead to different environmental pollution problems. Depending on the concentration of the pollutant and the duration of exposure to it, health risks posed by a specific pollutant can range from minimal to life-threatening.
- Water
Pollution of the water bodies is caused by direct discharge of sewage either from foul sewage outfalls or from sewage discharged into the stormwater drains with subsequent discharges into the sea without any treatment. The raw sewage is rich in organic matter which depletes the water of its oxygen content, causing malodorous conditions. It also contains nutrients which encourage the growth of micro-organisms. Serious sewage contamination is reflected by a poor grading of beach water quality and in some cases resulting in the closure of beaches.
Manufacturing industries consume a wide range of raw materials and produce complex waste effluents. Indiscriminate disposal of untreated trade effluents directly to surface drains and other watercourses poses a threat to the aquatic environment. Disposal of these wastes to sewers can adversely effect the operation of sewage treatment plants leading to contamination of coastal waters. This further leads to the accumulation to toxic chemicals in marine bottom sediments and transfer to humans through the food chain.
Waste
Quantities of solid waste to be handled by disposal authorities continue to increase as a result of the economic growth of the territory, and the gradual introduction of tighter controls over the disposal of chemical waste and wastewaters. These wastes, deriving from household, industry, construction, reclamation, livestock farming, power generation, water and wastewater treatment operations, can cause pollution of the air, water and land.
With the growing expectations of the community for a better environment, the need for implementing a cost-effective, secure and environmentally acceptable waste management programme is apparent. Special categories of waste such as chemical and clinical wastes, decomposing carcasses and various types of sludge also require tighter control, not only in respect of disposal but also on storage, transportation and treatment.