Soil gas sampling
Quantitative purge-and-trap with GC(–MS) is a common approach for the analysis of VOCs and SVOCs in soil, but it involves labour-intensive sample preparation and pre-screening analysis. Soil probes are a complementary approach to purge-and-trap for analysis of VOCs in soil vapour that overcomes many of these issues. Their use supports compliance with ASTM D7758.
Stainless-steel assemblies are inserted into the ground, allowing soil gas to be sampled in-situ onto a sorbent tube, either pumped or passively.
Established VOC air monitoring technology has also been applied to the monitoring of contaminated land, but the frequently-used approach of canister sampling excludes many heavier organic pollutants. Sampling onto sorbent tubes, followed by thermal desorption analysis, allows a much wider volatility range to be addressed. Soil probe technology therefore has the potential to significantly speed up and reduce the cost of surveys of contaminated land.
Monitoring contaminated land and petrochemical pipelines are the primary applications of soil sampling, but other applications include:
- Landfill/domestic waste sites
- Gasoline retail outlets and car service stations
- Active industrial sites
- Oil/gas pipeline monitors