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Proprietary findings to date support the hypothesis that excellent degradation potentials for petroleum contaminated soils may be obtained through the application of a number of aerobic (oxygen utilizing) soil biodegradation procedures, i .e. : 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 liquid inoculum and/or compost. . .with certain forms of compost having proven to be superior bulking agents, and source of non--pathogenic hydrocarbon utilizing bacteria and fungi, 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 which draw air through the treatment beds in order to maintain adequate supplies of oxygen within. Beds may also be covered to regulate temperature and protect against extreme weather conditions . Static pile aeration is a process similar to forced-air, however, no piping is placed within the bed as periods of cooler weather create conditions in which passive air flow into the bed provides adequate aeration as a result of the upward movement of biologi- cally heated air drawing the cooler ambient air into the sides of the beds . Windrowing is a process which utilizes a specially modified sods mixing machine to construct three foot high beds of amended soil . The beds are turned periodically to maintain aerobic conditions and break down clayey soils . This process is believed unique to local projects and has provided superior degradation rates. Thin-spread landfarming probably remains the most commonly used soils bioremediation protocol . Here, contaminated material is spread thinly (usually to a depth of 9-12 inches ) to permit passive aeration of inoculated/amended soils. In all cases, the treatment beds are carefully monitored to ensure that appropriate soil permeability, pH, moisture, and nutrient levels are maintained. Samples are also acquired for certified and uncertified analyses to determine rates of ' hydrocarbon degradation and the formation of degradation intermediate compounds . Final sampling for certified analysis is in accordance with regulatory agency guidelines with reduction of contaminants frequently below laboratory detection limits. 1 IV. r