At the Tata plant in Mithapur, effluent is taken to huge mud trenches, effluent-settlement ponds, which cover about 243 ha. The liquid is supposed to go to the sea from here after suspended solids in it settle down. According to the Consent to Operate given to the company in 2004, ponds marked S,T,U, V,W,X were in use, implying 18 ponds