THE ENVIRONMENT
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The first stage of the treatment system for pig manure at Ta Kwu Ling govern- ment farm is now in operation, and work on the second stage is underway. This system is being used to demonstrate to local farmers the types of more advanced waste treatment. Every effort is being made to show farmers that the removal of solids from pig buildings before hosing down will greatly reduce current pollution problems in watercourses.
Marine Pollution
A marine pollution unit has been set up within the Agriculture and Fisheries Department in order to establish base-lines for the evaluation of the level of pollution and its effects on the biota. This unit is responsible for investigations into pollution problems affecting fishery resources and for the well-being of the marine environment of Hong Kong. On-going investigations include productivity studies and surveys of benthic organisms, the results of which should be applicable to various decisions concerned with the dumping of sewage and preservation of fishery resources. The unit collaborates with the two universities and the Public Works Department.
Fish culture trials in the sewage effluents of the Shek Wu Hui pilot sewage treat- ment plant are being carried out by the Agriculture and Fisheries Department. Apart from ascertaining the feasibility of using the nutrients in the effluents for the produc- tion of animal proteins, tests are also being carried out to ascertain the edibility of the cultured fish-particularly in connection with the possible contamination by pathogenic bacteria and heavy metals.
The Marine Department's pollution control unit deals with the three main aspects of harbour pollution-oil pollution, harbour scavenging and refuse collection from ocean-going vessels.
Under the overall guidance of a marine officer, the unit maintains surveillance on all aspects of oil transfer to and from ships. A patrol launch is used for this purpose and regular and frequent checks are made on ships and oil installations throughout Hong Kong waters. Since the inception of the unit in 1971, many pollution offenders have been successfully prosecuted. The maximum penalty for polluting the waters of Hong Kong is $20,000 and six months imprisonment, plus the cost of clearing or dispersing the pollution. An additional fine of $4,000 can be imposed for failure to report oil pollution. The unit is equipped with stocks of oil dispersants, spray booms, sea-surface agitators and oil containment booms, and launches are always in a state of readiness to deal with oil pollution. A purpose-built launch equipped with modern pollution control facilities was commissioned in October 1975. There are VHF radio facilities to enable the on-scene commander to communicate and co-ordinate with the Port Communication Centre in the event of oil spillages.
The pollution control unit also operates scavenging services in the main harbour and the typhoon shelters at Aberdeen, Causeway Bay and Yau Ma Tei. To cover these operations, 23 craft are currently under contract to the government. Refuse is disposed of by land transport also under contract, and during the year an average of 11.7 tons of refuse was removed daily. Of this, 57 per cent was fragmented timber, with the remaining 43 per cent consisting of domestic and sundry refuse. The refuse collection