Perform maintenance on clarifier as follows: Overhaul clarifier drive units, blast & recoat clarifier submerged structural steel, blast & recoat non-submerged clarifier structural steel, blast & recoat clarifier launder troughs, replace clarifier weirs and scum baffles, replace aboveground conduit on clarifiers, apply non-porous, composite coating to interior of concrete clarifier walls, replace rubber seals & scrapers, and miscellaneous repairs as shown on the drawings.