A Case History of Dewatering and Recycling Sump Drilling Mud on 141 Wells in the Midway Sunset Field, California

Abstract

Abstract Significant savings have been realized at the Midway Sunset (MWSS) Field in Kern County, California through dewatering and recycling sump drilling fluid, thereby eliminating mud "disposal" costs and liabilities. A dewatering unit was introduced at MWSS in October, 1986, in an effort to reduce the high disposal cost of sump fluid. Disposal cost for non-hazardous liquid had risen from $10.10/bbl in October, 1986, to $16.40/bbl in May, 1987. Mud disposal cost represented 15% to 20% of the cost to drill and complete a MWSS well. Dewatering and recycling sump drilling mud reduced this disposal cost to $3.49/bbl and, thereby, lowered drilling costs by $ll,621/well (average). Continued utilization of this process on 141 wells drilled from October, 1986, through September, 1987 generated a savings of $1,638,561.