ARCHIVED REPORTS XR0001670 - Laserfiche WebLink

Home Browse Search

i s 3.4 Drum Sampling On June 21, 1994, water samples were collected from five (5) treated drums containing purge water (drums D-1 through D-5) These drums contained purge water from EW-1 and MW-14 and were inoculated with the same bacterial culture used for the pilot study The drums were inoculated on February 2, 1994 Samples were collected from each drum using a disposable plastic bailer The samples were collected in 40-m1 VOA vials The samples were labelled and transported under chain-of- custody to MM The five samples were composrted for analysis at the laboratory and analyzed for TPH as gasoline and BTE&X On June 22, 1994, three soil samples were collected from drums containing drill cuttings from the installation of B-1, VW-6 and VW-7 The soil drums were also inoculated on February 2, 1994 with the same bacterial culture used for the pilot study I The soil samples were collected from the drums using a metric soil sampler loaded with two clean, 2 by 3-inch brass sleeves The ends of the lead brass sleeve were covered with aluminum sheets, capped and sealed with tape The samples were collected from a depth of approximately 18 inches into the drum The samples were labelled and transported under chain-o£-custody procedure to AAL The Ile three soil samples were composited at the laboratory and analyzed for TPH as gasoline and BTE&X 4 0 FINDINGS ' 4.1 Groundwater Gradient and Direction The depth to first groundwater ranges from 58 feet at the north end of the site to nearly 61 ' feet southwest of the site The data indicates a 15 foot drop 1n elevation since March 1993 The drop in elevation is uniform throughout the site area and is consistent with seasonal (summer) decrease in groundwater elevations Figure 4 1s a groundwater gradient map, ' based upon the data collected on June 21, 1994 Groundwater flow in the vicinity of the site is south-southwest, the gradient steepens towards the south end of the site ' 42 Petroleum Hydrocarbon Impacted Groundwater Petroleum hydrocarbons were detected in samples from six of the eight wells TPH ranged ' from 71 ppb (MW-11) to 990 ppb (MW-6) Detectable BTE&X concentrations ranged from 0 53 ppb (toluene, MW-10) to 58 ppb (xylenes, MW-14) No TPH or BTE&X were detected in samples from MW-12 and MW-13 The analytical results are summarized in Table 2 The ' Iaboratory results and chain-of-custody are included in Appendix B Qmbanl Audit k-- Ine 8 ' l33I&Sf '31DM QM{ v