Soil Vapor Sampling
Direct sampling from the PRT using a gas chromatograph-compatible syringe used in conjunction with a mobile laboratory and gas chromatograph for immediate analysis of the collected samples.
Inline sampling using glass sampling bulbs or Tedlar bags. The sampling device is placed inline, between the PRT adapter and the vacuum volume system. As the sampling system is purged, soil gas is trapped in the bulb or bag. These samples may be stored for limited periods of time and either analyzed on site or at an off-site laboratory.
Summa canisters, (pre-evacuated steel devices that are connected to the surface end to the PRT tubing), also provide another sampling option for soil gas. A valve on the canister is opened and the vacuum inside the canister pulls in soil gases from the sample interval. This system is expensive and is usually reserved for sending samples to an off-site laboratory for specialized analyses or quality control purposes.
