Superfund Innovative Technology Evaluation (SITE)
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|Field Measurement Technologies for Total Petroleum
Hydrocarbons in Soil Dexsil® Corporation PetroFLAG System
The PetroFLAG System developed by Dexsil® Corporation (Dexsil) was demonstrated under the U.S. Environmental Protection Agency Superfund Innovative Technology Evaluation Program in June 2000 at the Navy Base Ventura County site in Port Hueneme, California. The purpose of the demonstration was to collect reliable performance and cost data for the PetroFLAG System and six other field measurement devices for total petroleum hydrocarbons (TPH) in soil. In addition to assessing ease of device operation, the key objectives of the demonstration included determining the (1) method detection limit, (2) accuracy and precision, (3) effects of interferents and soil moisture content on TPH measurement, (4) sample throughput, and (5) TPH measurement costs for each device. The demonstration involved analysis of both performance evaluation (PE) samples and environmental samples collected in four areas contaminated with gasoline, diesel, or other petroleum products. The performance and cost results for a given field measurement device were compared to those for an off-site laboratory reference method, Test Methods for Evaluating Solid Waste (SW-846) Method 8015B (modified). During the demonstration, Dexsil required 50 hours, 40 minutes, for TPH measurement of 181 samples and 10 extract duplicates. The TPH measurement costs for these samples were estimated to be $6,390 for the PetroFLAG System compared to $38,560 for the reference method. The method detection limits were determined to be 20 and 6.32 milligrams per kilogram for the PetroFLAG System and reference method, respectively. During the demonstration, the PetroFLAG System exhibited good precision and ease of use. The devices mean responses for interferents that are considered to be petroleum hydrocarbons were mixed (0 and 42.5 percent for neat methyl-tert-butyl ether and Stoddard solvent, respectively). The devices mean responses for interferents that are not considered to be petroleum hydrocarbons were also mixed (1.5, 103, and 16 percent for neat tetrachloroethene; turpentine; and 1,2,4- trichlorobenzene, respectively, and 2.5 percent for soil spiked with humic acid). In addition, an increase in soil moisture content biased the devices TPH results low for weathered gasoline soil PE samples. Based on action level conclusions and statistical correlations, the PetroFLAG System TPH results compared well with those of the reference method; however, the device exhibited a high bias, and its TPH results were determined to be statistically different from those of the reference method. Collectively, the demonstration findings indicated that the user should exercise caution when considering the device for a specific field TPH measurement application.