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water analyzer Monitoring well stabilization data and field sheets are included in Appendix D The water was placed in labelled DOT-approved drums and stored on-site 3.2.2 Groundwater Sampling Water samples were collected from each well using clean, disposable plastic bailers The isamples were collected in 40-ml EPA vials Samples were transported in a chilled container to McCambell Analytical in Pacheco (MAI) The samples were analyzed for total petroleum hydrocarbons (TPH as gasoline), volatile aromatics (BTE&X) and volatile halocarbons in accordance with EPA methods 8015m, 602, 601, respectively The sample from MW-14 was also analyzed for ethylene dibromide (EDB) in accordance with EPA method 601 Samples were also collected from each well for bacteriological analysis Samples were collected in 40-m1 VOA vials and transported to Applied Biotics in Bakersfield, California and Midwest Laboratories, Inc (MLI) in Omaha, Nebraska ' 4 0 FINDINGS 41 Biological Activity in Ground-*�ater ' The bacteriology continues to indicate increased microbial activity Samples analyzed by MLI provide information on aerobic and anaerobic plate counts (see Appendix B) Discussions with MLI indicated that normal groundwater background concentrations of aerobic and anaerobic bacteria are generally in the range of 100 to 300 cfu/ml concentrations in all wells sampled indicate significant increases over "normal" ' concentrations Aerobic plate counts ranged from 290,000 cfu/ml (NNW-9) to 500,000,000 cfu/ml (MW-14) ' Anaerobic plate counts ranged from 13,000 cfu/ml (MW-12) to 63,000,000 (MW-14) MW- 14, currently the well with the greatest concentration of hydrocarbons, contains the greatest concentration of aerobic and anaerobic bacteria Additional samples will be transmitted to ' MLI during the first quarter of 1995 to determine if the trend continues Analysis of water samples by Mr James Hoeltgen (Table 1, Appendix B) also indicates ' increased biological activity Between 4 and 6 species of hydrocarbon degraders are being identified in the water samples, primarily Pseudomonas (gram negative) However, no P Aeroginosa have been identified to date (none were used in the inoculum) It is likely that many of the bacteria present are naturally occurring and are thiiving because of the abundant "food" source (hydrocarbons) However, both the MLI and Hoeltgen data ' indicate that bacteiia are present at elevated levels and, more specifically, specific species from the inoculum are still present and active Qe-0l-91 Ada S.,— 1Pe Quanerly RepoM2 941133 C,EWQM6