Chemical sensor and field screening technology development: fuels in soils field211 screening method validation

摘要

A new screening method for fuel contamination in soils was recently developed as211u001eAmerican Society for Testing and Materials (ASTM) Method D-583 1-95, Standard 211u001eTest Method for Screening Fuels in Soils. This method uses low-toxicity chemicals 211u001eand can be used to screen organic-rich soils. In addition, it is fast, easy, and 211u001einexpensive to perform. The screening method calls for extracting a sample of 211u001esoil with isopropyl alcohol following treatment with calcium oxide. The resulting 211u001eextract is filtered, and the ultraviolet absorbance of the extract is measured at 211u001e254 nm. Depending on the available information concerning the contaminant fuel 211u001etype and availability of the contaminant fuel for calibration, the method can be 211u001eused to determine the approximate concentration of fuel contamination, an 211u001eestimated value of fuel contamination, or an indication of the presence or 211u001eabsence of fuel contamination. Fuels containing aromatic compounds, such as 211u001ediesel fuel and gasoline, as well as other aromatic-containing hydrocarbon 211u001ematerials, such as motor oil, crude oil, and coal oil, can be determined. The 211u001escreening method for fuels in soils was evaluated by conducting a collaborative 211u001estudy on the method and by using the method to screen soil samples at an actual 211u001efield site. In the collaborative study, a sand and an organic soil spiked with 211u001evarious concentrations of diesel fuel were tested. Data from the collaborative 211u001estudy were used to determine the reproducibility (between participants) and 211u001erepeatability (within participant) precision of the method for screening the test 211u001ematerials. The collaborative study data also provide information on the 211u001eperformance of portable field equipment versus laboratory equipment for 211u001eperforming the screening method and a comparison of diesel concentration values 211u001edetermined using the screening method versus a laboratory method. Data generated 211u001eusing the method to screen soil samples in the field provide information on the 211u001eperformance of the method in atypical real-world application.