Laserfiche WebLink
Page 1 of 1 <br /> Vicki McCartney [EH] <br /> From: William Little [wlittle@advgeoenv.com] <br /> Sent: Saturday, July 31, 2010 11:31 AM <br /> To: Vicki McCartney [EH] <br /> Subject: Ripon Farm Service <br /> Attachments: TABLE OF EPA METHODS.pdf <br /> Vicki, <br /> In response to the EHD letter dated 02 July 2010 the following is presented to comment on the content of the <br /> letter: <br /> Additional chromatograms for TPH-d QA/QC for epa method 8260 are'not available, as the GCMS method did <br /> not use a TPH-D standard for evaluation.A notation on the base of the analysis, states TPH-d was performed by <br /> CG/MS analysis for TPH-d range compounds and the detection limit is 20,000 micrograms per cubic meter. <br /> The GRO detection by epa method 8260 was greater than the potential detection by epa method 8015; epa <br /> method 8260 is more sensitive to all compounds.The preferred analysis for fuel additives are by epa method <br /> 8260, not by epa method 8020 nor by epa method 8015.The sensitivity of epa method 8015 is one of the <br /> poorest amoungst methods used for waste characterization; reportedly due to the high volume of sample <br /> required and associated matrix interference. Attached is table.referencing the methods and devices used. <br /> GC/MS is used for both volatile and semi-volatile, however an extraction use in the SV method is replaced, by <br /> an air matrix in the vapor samples. <br /> The report states the GRO was reported by epa method 8260. <br /> William R. Little <br /> California Professional Geologist 7473 <br /> Oregon Registered Geologist G2254 <br /> Washington Licensed Geologist 2778 <br /> Advanced GeoEnvironmental Inc. <br /> Stockton-Santa Rosa-Monterey-Brea-Spokane-Reno <br /> (800)511-9300 <br /> I <br /> 8/2/2010 <br /> t <br />