Experiments were performed to determine if an isolated Arthrobacter globiformis SBI-5 could enhance degradation of JP-5 fuel added to natural waters (i.e., pond water) and to two types of soil, sand and potting soil). When JP-5 fuel was added to the pond water (2.5%, v/v), the natural flora possessed the ability to degrade the JP-5 fuel with an efficiency nearly equalling that displayed by SBI-5 under specialized culture conditions (addition of yeast extract and other growth promoting materials). When SBI-5 was added to pond water containing its natural viable flora, degradation of JP-5 fuel was depressed. The addition of yeast tract to a similar culture of pond water partially promoted the growth of SBI-5. The loss of JP-5 fuel from the soil samples over time was similar regardless of the presence or absence of the jet fuel degrading microbe (e.g., SBI-5) or its biosurfactant.