Characterization and Treatment of Leachates from Hong Kong Landfill Sites

Development of a large landfill site in the North-Eastern New Territories of Hong Kong, which will receive 25 million m³ of wastes during a life of about 13 years, must include the provision of a scheme to manage leachates which will arise in the tropical climate of the region.
The paper presents detailed results from a study commissioned by the Environmental Protection Department of the Hong Kong Government, to characterize and treat leachates generated by landfills in Hong Kong, in order to design a suitable management scheme. Field and laboratory trials which were carried out during 1989 showed that, although leachates from Hong Kong landfills have some specific characteristics (e.g. concentrations of amm.N to 5000 mg/l), they can be treated to high standards by aerobic biological processes.
As a result of these studies, a scheme has been designed which will provide a high degree of environmental protection in respect of leachate, as the landfill is developed.     

The New Zealand Rural Water Supply Concept and the Developing World

T he historical development of the New Zealand rural water supply concept is described, and the basic principles are explained in terms of both its design features and reliance upon community involvement during the promotional, constructional and operational phases.
Conceptional and cost comparisons are made between the New Zealand rural water supply concept and its urban counterpart, and an analysis is undertaken of the transferability of the concept to a developing world situation with the consequent emphasis on low-cost construction and self-help operation.
The adoption of the New Zealand model is advocated as a potential design concept for a range of defined circumstances in developing countries.