Tender For providing of custom bid for services - once thorough mechanized desludging of septic tanks and aqua privies by cesspool emptiermachine and high power suction system at all stations under sealdah division total no of tank 1599 volume 16989 cum approx to be compl..,custom bid for services - mechanized cleaning of underground sewer line of 6 9 12 inch dia at specified areas with high pressure suction high pressure jet sewer rodding machine for once in each year and to be continued for 03 years total length 141..