Abstract: Seasonal chemicals characteristic of leachate were studied in conjunction with process performance of leachate treatment units. Samples were taken from leachate collection pond, sedimentation outlet, filter outlet and effluent pond outlet. Monthly results of thirty quality parameters showed that TDS, SS, BOD and COD were characterized wet season physiochemical performance. The presence of high sulphide was the main chemical characteristic of leachate in dry season. The presence of high level of ammonia, exceeding hundreds fold of effluent standard, might be the determination factor in leachate treatment. This was brought about insufficient results of separation technique for the existing leachate treatment. Biodegradability level indicated the leachate was biodegradable, suggesting microbial treatment will be appropriate instead of separation technique.