Refiner biodegrades separator-type sludge to BDAT standards

This paper reports on bioremediation that has been successfully used to treat sludge from a refinery stormwater surge basin at the Murphy Oil USA Inc. refinery in Meraux, La. The technique can be used for numerous basins recently reclassified as hazardous waste units because thy contain listed waste, specifically primary and secondary oil/water/solids separation sludge, or F037 and F038. Approximately 9,000 cu yd of high oil and grease sludge accumulated in the storm water basin at the Meraux refinery. ENSR Consulting and Engineering performed a feasibility study on the sludge to determine if it degraded at a rate sufficient to justify a full-scale operation. Data from the feasibility study was used to scale-up to a 730,000 gal (in situ) reactor. The residual from the sludge degradation process was: noncharacteristically toxic-based according to the toxicity characteristic (TC); below land-ban standards for API separator bottoms (a listed refinery waste of similar composition).