Soil Gas Assessment, Vapor Intrusion Risk Assessment, and Mitigation
Intrusion of toxic volatile organic compound (VOC) vapors into indoor air from underlying contaminated soil and groundwater has emerged as a primary exposure pathway of human health risk. Vapor intrusion risk assessments are now required by many state and local agencies as a condition of closure or "No Further Action" (NFA) at VOC impacted sites. This indoor air quality issue can present a significant potential liability and may result from onsite or offsite volatile organic compound contamination. In addition, a significant indoor air vapor intrusion condition can .jpg)
create a toxic tort liability and may affect your business operations if left unmitigated (e.g., California Proposition 65).
EMS offers over 20 years of expertise in soil gas surveying services that provide real-time evaluation of soil contamination by volatile organic compounds (VOCs) using our fleet of Geoprobe Systems™ hydraulic direct-push probe rigs and California ELAP certified mobile laboratories. Our ability to analyze soil gas samples on-site allows for optimum placement of subsequent probes based on current data, in turn, eliminating the wasted time and expense of unnecessary sampling and analysis. Our extensive experience with soil gas sampling and chemical analysis allows us to provide rapid, high-quality data for the evaluation and modeling of vapor intrusion conditions.
EMS has extensive experience in installing near-slab and sub-slab soil gas probes specifically designed for vapor intrusion testing. Soil gas samples are collected by our trained mobile laboratory chemists for analysis in our California state-certified
mobile laboratories to provide quick and accurate analytical results. Our mobile laboratory equipment is capable of achieving detection levels for VOCs below California Human Health Risk Screening Levels (CHHSLs) for shallow soil gas at commercial and residential sites at extremely competitive costs. When soil gas testing and vapor intrusion risk evaluation is necessary, you can be sure that the proper procedures, laboratories, and quality assurance protocols will be followed and provided, and that the resulting data will be defensible.
EMS owns, installs, maintains and operates packaged vapor extraction (VE) systems for the treatment of soil impacted by (VOCs including common solvents, dry cleaning chemicals and motor fuels. These systems are used for remediation of 
VOC-impacted soil and for mitigation of VOC vapor intrusion (VI) conditions at existing buildings. EMS maintains South Coast Air Quality Management District (SCAQMD) Various Locations Permits for use at sites located throughout Southern California. Typical systems include 100 to 600 cubic feet per minute (cfm) vacuum extraction blowers equipped with moisture/water removal tanks and particulate filters followed by activated carbon filters for removal of VOCs from the influent gas stream. EMS specializes in the monitoring and efficiency testing of our soil vapor extraction and VI mitigation systems.