Rapid Detection of Volatile Organic Compounds in Groundwater by in Situ Purge and Direct-Sampling Ion-Trap Mass Spectrometry

Site characterization for subsurface contaminants is time-consuming and costly. The Tri-Service Site Characterization and Analysis Penetrometer System (SCAPS) has been developed to reduce the time and cost required for site characterization. Probes are designed to detect specific classes of contaminants such as petroleum products, explosive compounds, volatile organic compounds (VOC), and others. This article describes the Hydrosparge VOC sensor, an in situ VOC detection system that is capable of rapid subsurface site characterization of VOC contaminant distribution. The system consists of a direct push well for groundwater access, an in situ sparge module, and a direct-sampling ion-trap mass spectrometer. The results obtained with the SCAPS in situ technique indicate a strong linear relationship with EPA methods (r² = 0.84). SCAPS Hydrosparge VOC sensor has been demonstrated to reduce the time and cost required to characterize sites by directing the placement of a reduced number of conventional monitoring wells.