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i, .,, 17, 21, 24, and 28. In all samples, bacterial diversity and abundance were lower than the control sample from EW-1 collected on February 2, 1994 (Table 1). There is no indication that the introduced bacteria reached groundwater in the vicinity of MW-14 during the February monitoring. In accordance with the monitoring plan, GeoAudit attempted to collect water samples from MW-4. However, on both February 7 and 10, the well contained less than 1 foot of water and,did not recharge. Samples were collected, but are probably are not representative of current groundwater. Instead, this water is believed to have been left behind in the bottom of the well .after groundwater dropped below the screened interval. In these two samples, diversity was low but abundance was moderately high. Coliform bacteria were also detected on February-,10 (Tables 1 and Attachment A). No measurable water was present in MW-4 on February:.141, 17, 21 or 28. Because of the lack of water present in MW-4, on February 28, GeoAudit began to collect samples from EW-1 in order to have more groundwater data available. The results of the test are-included in Table 1. The laboratory results are included in Attachment B. Dissolved 02 and CO2 Analysis Groundwater samples were also collected from MW-4 and MW-14 for analysis of dissolved oxygen.and carbon dioxide. The purpose of these analyses is to determine a relationship, if OF any, between the dissolved gases in the groundwater and the presence of bacteria. The laboratory analysis are included in Table 2. The laboratory results are included in Attachmenx C. No clear trend can be seen in the data. Dissolved carbon dioxide and oxygen concentrations have fluctuated since inoculation. Bacteriological data from early-Marcfi may help identify a trend. - _As was the case with the bacteriological data, the initial sample collected from MW-4 is probably not representative of groundwater. VAPOR MONITORING Field Screening Field-screening of carbon dioxide-and oxygen vapor readings was performed in January, before inoniation, and on February 10, 14, 17, 21., 24, and 28 after inoculation. Screening was performed using GasTech oxygen and carbon dioxide meters. Readings were collected from each.M- well (MW-4, VW-1, VW-4, VW-5, and VW-b) as well as MW-1, MW- 14, MW-5, VW-7, VW-2, and VW-3. The results of the field vapor monitoring are - y summarized in Table 3. The data indicate that CO2 concentrations were near zero prior to i 1 0-b0-1 A.&So-i*lie. 2'1 CONEmon6ly moeit��s2-9i