Envco – Environmental Equipment

Soil Gas Samplers
Soil gas samplers are used during soil gas surveys and/or active soil gas investigations to discover information about soil and groundwater contamination, primarily volatile organic contaminant (VOC) levels. The ability to detect elevated VOC levels in soil gasses allows investigators to pinpoint locations for future soil and groundwater sampling.

Features
• Provide valuable data on the distribution and concentration of VOC's in soil and groundwater
• Rapidly collect the sample at specific depths
• Penetrate to sampling point quickly
• Easy to use and easily adapts to existing tooling
• Inexpensive survey tool for sample collection from shallow depth well to beyond 50 feet below ground surface (bgs)
• Use in a wide variety of methods
• Use telescopically through AMS hollowstem augers and dual tube sampling systems

Monitoring Soil Gas
AMS PowerProbes can be used to install soil gas monitoring systems, including soil gas monitoring wells, around underground storage tanks or as part of an ongoing remediation efforts. Soil gas monitoring systems are used for long-term soil gas monitoring and repeated sampling of volatile contaminants in the vadose zone. They act as an active method for soil gas retrieval which can be used in all phases of a soil gas investigation. Soil gas monitoring wells are not recommended for obtaining screening-level analytical data for soil gas surveying.

Benefits include:
• Installation in a variety of subsurface lithologies to depths up to 100 feet bgs
• Long-term installation that allows repeated sampling of the same location
• Representative sample collection, useful for soil gas monitoring programs

Recommended Soil Gas Monitoring applications:
• Soil gas vapor monitoring wells
• Soil gas samplers offered by AMS can be established as long-term installation for monitoring soil gas vapor

Soil Gas Sampling Application:
Single Tube Procedure
Designed to be pushed single tube without pre-boring and collect a point source soil gas sample. Separate the expendable tip from the direct push rods once you have reached the desired sampling depth, and then withdraw the rods a few inches to expose the soil. A vapor sample is collected using a vacuum pump and tubing that opens into the sample chamber. To sample deeper, the probe must be withdrawn and another expendable tip attached.

Recommendation: Use the 1 1/4" or 1 5/8" expendable tip for a single tube
install.
• Ability to penetrate
• Efficient rate of penetration
• Seal the top
• Expend the tip
• Purge the ambient air at low flow
• Finish by extracting the sample using a low flow vacuum

Telescopic Procedure
While soil gas collection is easily done through an open borehole, the collection of soil gas using a cased, dual tube system or hollowstem auger will allow for the sampling inlet to be isolated at a specific depth and minimize the chance of cross contamination.

Recommendation: Use the 1 1/4" or the 1 5/8" expendable tip for a dual tube
install.
• Drive down with dual tube system
• Pull out internal dual tube components
• Drop Bentonite
• Hydrate with water
• Drop the single tube down
• Push through Bentonite, generating a seal
• Purge the ambient air at a low flow
• Finish by extracting the sample using a low flow vacuum

Long-Term Implant
Installation Procedure
Implants for long-term soil gas monitoring can be installed either with the single tube or telescopic direct push procedures. Once the direct push tooling used to install the implant is pushed to the chosen depth, the implant is then placed through the tooling. The tooling is retracted and the implant is isolated at the chosen depth, and then completed similar to a procedure that would be used to install a groundwater monitoring well.