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BioOvr - Page 4 for metabolic attack on a particular hydrocarbon are active, or even produced. A number of aerobic soil biodegradation protocols have been found to offer excellent degradation potentials for petroleum contaminated soils . These are: Forced Air Composting Windrowing Static pile Aeration Thin-spread Landfarming Forced air composting has been utilized during periods of inclement weather and under circumstances where space for treatment is limited. It involves the thorough mixing of contaminated soil with organic material . . .with certain forms of compost having proven to be superior bulking agents and sources of non-pathogenic hydrocarbon utilizing bacteria and fungi , as well as a supplier of nutrients , minerals , and moisture. The amended soil is then formed into large, quadrilateral beds through which slotted piping is placed. The piping is then connected to pumps that draw air through the beds in order to maintain adequate levels of oxygen within. Beds may also be covered to regulate temperature and protect against extreme weather conditions . Static pile aeration is similar to forced-air composting, except that no piping is placed within the treatment bed as periodic cooler temperatures create conditions favorable to the passive movement of air into the beds . This air then heated and moves upward as a result of biological activity, drawing cooloer, ambient air into the bed. Windrowing is a process that utilizes a specially modified soils mixing machine to construct three to five foot high beds of amended soil . The beds are turned periodically to maintain aerobic conditions and adjust soil particle size. With thin-spread landfarming, contaminated soil is spread thinly (usually to a depth of 9-12 inches) to permit passive aeration and make permit further mixing. In all cases, the treatment beds must be carefully monitored to ensure that appropriate soil conditions exist for the development and maintenance of high biomass. Direct readings , and uncertified/certified analyses are taken to determine rates of hydrocarbon degradation, soil moisture, pH, and nutrient levels . Final sampling for certified analyses is in accordance with regulatory agency guidelines with contaminants frequently reduced to below laboratory detection limits .