Rapid detection of volatile organic compounds in the subsurface by membrane introduction into a direct sampling ion-trap mass spectrometer

The Triservice Site Characterization and Analysis Penetrometer System (SCAP S) was developed to reduce the time and cost required for site characteriza tion. Direct-push sensors were developed to detect specific classes of cont aminants, such as petroleum hydrocarbons, explosive compounds, radionuclide s, metals, and volatile organic compounds (VOCs), This article describes th e demonstration of a direct-push sensor that can quantify VOC contamination in the subsurface in real time. This system consists of a membrane interfa ce probe (MIP) manufactured by Geoprobe Systems coupled to a direct samplin g ion-trap mass spectrometer (ITMS), The ITMS-MIP system was shown to rapid ly collect and analyze samples from the subsurface, regardless of matrix. T wo of the five demonstrations discussed resulted in a strong linear correla tion (r(2) = 0.9) with validation samples analyzed using EPA Method 8260, T he other three demonstrations revealed that the calibration method used in this work introduced a bias compared to EPA methods.* (C) 2000 John Wiley & Sons, Inc.