Laserfiche WebLink
B 6.5 Blanks <br />' In addition to the groundwater samples, a trip blank and a decontamination blank are analyzed <br /> during each sampling round A 40-m1 glass VOA bottle with a Teflon septum lid, filled with DI <br />' water at the laboratory, functions as a trip blank This trip blank travels with the sample kit from <br /> the laboratory to the facility and back to the laboratory again in the sample cooler The blank is <br /> analyzed for the same parameters as the samples to indicate if the samples have been <br /> contaminated, from whatever source, during the trip from the site to the laboratory <br /> A decontamination blank 1s prepared in the field during well sampling After the first well is <br />' sampled, DI water is poured into the clean, rinsed sampling bailer that is to be used for sampling <br /> the next well This DI water is then emptied, as a sample, into a preserved 40-m1 VOA bottle for <br /> analysis with the samples and trip blank The decontamination blank indicates if any of the <br />' samples are contaminated from the sampling equipment or decontamination process <br /> B 6.6 Sample Analysis <br /> All groundwater well samples, the trip blank, and the decontamination blank are analyzed by the <br /> laboratory according to Table 2 of the "Tri-Regional Board Staff Recommendations for <br />' <br /> Preliminary Evaluation and Investigation of Underground Tank Sites," typically for Total <br /> Petroleum Hydrocarbons as gasoline (TPH-g) by DHS-modified EPA Method 8015 and for the <br /> aromatic hydrocarbons benzene, toluene, ethylbenzene, and xylenes (BTEX) by EPA Method <br /> 8020 <br /> 1 <br /> 1 <br />' WP61 73942 R01397 APB 1 B-5 <br />