tender for operation , repair & maintenance of sewage treatment plant of 1.00 mld cap. at khopari, 0.50 mld capacity at chuhabag, 3 no. septic tank of 50000 ltrs, cap. each which i/c inlet chamber, grit chamber, partial flume, aeration tank, settling tank sludge drying beds, control valves, mechanical & electrical equipments, lighting system in the compound maintenance of lawns & garden and plant building including pump house, bod, cod, other parameter of testing lab. complete and operation & maintenance of sewerage net work of various diameters 12.94 kms length including civil structure complete to the entire satisfaction of engineer-in-charge for a period of 36 months.