Rapid detection of volatile organic compounds in groundwater byin situ purge and direct-sampling ion-trap mass spectrometry

A borehole geophysical method for detection and quantification of dense, non-aqueous phase liquids (DNAPL) in saturated soils

“…The method can provide discrete vertical samples of DNAPL presence and speciation, but the method is semi-quantitative and samples a very small soil volume. A similar method uses helium gas to purge VOC and bring the purged gases to the surface (Davis et al, 1998).…”

Using Direct‐Push EC Logging to Delineate Heterogeneity in a Clay‐Rich Aquitard

“…D‐P electrical conductivity (EC) logging has been shown to be very successful for high‐resolution hydrostratigraphic definition of floodplain sand and clay deposits (Butler et al 1999; Schulmeister et al 2003), while cone penetrometer technology (CPT) also enables detailed sediment characterization through measurements of geotechnical properties (Lunne et al 1997). Discrete multilevel sampling of ground water for inorganic (Schulmeister et al 2001, 2004) or organic (Davis et al 1998; Costanza and Davis 2000) chemical analysis and hydraulic tests (Butler et al 2002) has been made possible through the development of specially designed screens at the end of D‐P rods. The D‐P EC, hydrochemical, and hydraulic techniques all enable rapid, direct measurements to be made at any desired vertical resolution in the aquifer.…”

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

“…1,2 The Hydrosparge VOC sensor, which consisted of an in situ groundwater sparge device coupled to an ion-trap mass spectrometer (ITMS), proved to be the Correspondence to: J. Costanza Contract grant sponsor: Environmental Security Technology Certification Program Contract grant sponsor: U.S. Army Environmental Center most efficient way of characterizing VOC contamination in ground water at North Island, California. 3 The sensor is limited to measuring VOC contamination in ground water and is capable of only one measurement per in situ event.…”