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Bioremediation Pilot Test Results - 2 - 3 June 1994 Geweke Program A consisted of monitoring for the presence of bacteria in the ground water monitoring wells which appeared most likely to be impacted by migrating bacteria, MW4 and MW14. MW4 was the only inoculated monitoring well. Packers were placed in MW4 to prevent the bacteria from reaching ground water during inoculation. MW14 was the nearest downgradient well to MW4. Bacterial content in ground water was first analyzed in MW14 and MW4. However, MW4 went dry after several samples were collected and was replaced with EW L Samples were collected and analyzed twice weekly for two months. Observations and Comments: 1. Coliform bacteria were detected in several samples from the three wells; MW4, MW14, and EW 1. 2. P. aeruginosa (the potential pathogen) was not detected. 3. The number of different species present in each sample was provided. More than 8 species were reportedly present in the inoculum. From one to four species were reported in the ground water samples. 4. The species were not identified. 5. The bacterial numbers in MW14 fluctuated but remained under 450 bacteria/ml.. 6. Not enough samples were collected from MW4 and EWl to determine any trends in population. 7. Without species identification it is not possible to determine if the inoculated species were present in ground water. TABLE 2: ANALYTICAL RESULTS OF SOIL SAMPLES, TPH as Gasoline and BTE&X VWl had been inoculated with bacteria. The stratigraphy and contaminant distribution were well documented in VWL The first boring of the Pilot Study was installed 30 days after inoculation, about 2.5 feet from VWL The second boring was installed 60 days after inoculation, about 2.5 feet from the first boring and 5 feet from VWL These soil samples were collected in an effort to determine if hydrocarbon concentrations are lower in the soil after bacterial inoculation. Observations and Comments: 1. A map showing the locations of the two borings was not provided. 2. The boring logs were not provided. 3. Hydrocarbon concentrations and the soil sample depths were provided for the first new boring (PI), the second new boring (P2), and the boring for VW 1 (BI). 4. Hydrocarbon concentrations were higher in B1 and P2 than in Pl. 5. A loose interpretation of this data is that the bacteria moved the 2.5 feet from VWl to Pl in February and reduced the soil contamination. However, in two months the bacteria did not move an additional 2.5 feet to P2. 6. A stricter interpretation of the data is that the first boring was installed in a location without much contamination and the second boring was installed in a location with a lot of contamination. 7. The only real conclusion is that the borings did not provide enough data to determine that the bacteria caused the lower contaminant concentrations in boring Pl. 8. Without the logs and boring locations, the data has limited value.