This GC has been designed to meet the needs of Geoprobe™ operators worldwide. With one easily transported unit, you can measure continuous total VOCs in the Geoprobe purge gas, and then, with a simple software switch, inject the gas into the capillary column for speciation and separation of the individual VOC compounds.

The three detectors—FID/DELCD combination detectors and a PID detector—are plumbed in series so that the Geoprobe purge gas flows through each detector sequentially. The PID responds to all aromatics molecules (benzene, toluene, etc.) and many chlorinated VOCs (TCE, PCE, etc.). The FID responds to all hydrocarbons (methane, propane, etc.), and the DELCD responds only to chlorinated or brominated compounds (vinyl chloride, DCE, TCE, PCE, etc.).

The system is configured so that a solenoid valve, actuated by the PeakSimple data system, can direct the Geoprobe purge gas either directly to the detectors for a continuous total measurement, or it can direct the Geoprobe purge gas to a 1mL loop on the included gas sampling valve for injection into the GC column. Once injected into the column, the VOCs are separated and measured as individual compounds. This allows the Geoprobe operator to immediately profile the VOCs onsite either in real time as the probe is pushed, or later by locating the probe at specific depths where the total VOC measurement indicated VOC hotspots.