for week of August 7, 2006:
Mud pit (noun) The pit (either an above-ground metal tank or an excavated below-ground pit) that contains the drilling fluid. The mud pit is a series of dug earthen pits or metal open top tanks, through which the drilling mud is cycled to allow drill cuttings and sediments to settle out. If necessary to maintain system volume and quality, additives are mixed with the mud in the pit, and the fluid is temporarily stored there before being pumped back down the borehole. Also termed settling pit , shaker pit , shale pit , or suction pit , depending on the primary purpose.