SITE INFORMATION AND CORRESPONDENCE

Home Browse Search

Bioremediation Pilot Test Results - 6 - 3 June 1994 Geweke QUARTERLY REPORT: MARCH 1994 TABLES 3 AND 4: Ground Water Samples - TPHg, BTEX, DCA, EDB, and Lead The regular quarterly ground water monitoring was conducted in March 1994, as required in the Cleanup and Abatement Order. Results and Comments: 1. MWI, MW2, MW3, MW4, and MW5 were dry (they were all contaminated in the past). 2. MW6, MW7, MW8, MW9, MW 10 , MW 14, and EW 1 continue to show ground water contamination. 3. MW 10 and MW 1 I had contamination in two consecutive quarters and the concentration in MW II has increased 10 fold. 4. MW 12 is downgradient of the source area and had contamination for the first time. 5. MW 13 was the only well that did not have detectable levels of contamination. 6. Based on the results from MW 10, MW 11, and MW 12, the contaminant plume may be spreading 7. MW4 was the only monitoring well that was inoculated. Packers were used to prevent the bacteria from being placed directly in the ground water. At the time of inoculation the well had a few feet of water in it. However, after one sample was collected the well went dry and did not recharge. There was not enough data from one sample to draw any conclusions. 8. DCA has been detected in EWI, MW8, MW9, MW13, and MW14. Lead has been detected in EW 1, MW6, MW7, and MW 10 through MW 14. EDB has been detected only in MW 14, the well closest to the source of contamination. Summary Comments and Conclusions I. The ground water contaminant plume may be spreading downgradient. 2. Cover letters from the responsible party were not attached to the two recent reports; the "Quarterly Report: March 1994" and the first pilot study "Monthly Monitoring Report". 3. Lack of location maps and boring logs limited the conclusions we could draw from the soil data that was presented prior to the meeting.. 4. Addition of air into the subsurface appeared to disrupt the ability to detect in-situ changes in O, and CO, concentrations. 5. Based on the most data points from air samples analyzed with field instruments, wells that were inoculated showed the same trends as the inoculated wells. It is not possible to determine whether the trends in concentrations were caused by inoculation of bacteria. 6. The pilot study results were inadequate and inconclusive. In many cases, there were not enough data points to be able to determine any trends. In order to provide more data, many more analyses would have to be done. Even if more data were collected, it may not be possible to draw any conclusions about the effectiveness of bioremediation. Attachments