2. Materials and methods
2.1. Landfill leachate
The leachate samples were collected from a municipal waste
sanitary landfill (Pulau Burung Landfill Site, PBLS), located within
the Byram Forest Reserve, Penang, in the northern region of Malaysia.
Its geographical coordinates are 5240N, 100240E. The site was
developed semi-aerobically in March, 2001, and has a natural marine
clay liner with the total area of 33 ha [13].
The leachate samples were collected from the active detention
pond with a leachate age of less than 5 years, and instantaneously
transported to the laboratory, and stored in darkness at 4 C with
minimum exposure to surrounding air as to minimize the chemical
and biological changes. The characteristics of leachate samples