Hazards surround us every day. From sharing the road with my teenage son (best give him room) to the foods we eat (E. Coli with your romaine?), to the hands we shake (pre-COVID of course), everything has risks. Managing these risks is what allows us to focus on family, fun, and work (even if not always in that order). Environmental risk management is no different.
For the past two decades, vapor intrusion has been the exposure pathway of greatest concern with environmental contamination when compared to groundwater ingestion and soil exposure. This is easy to understand. As direct groundwater ingestion in metropolitan and industrialized areas is increasingly less common given municipally managed drinking water.
Similarly, direct exposure to contaminated soils is an exposure pathway easily managed through removal and/or engineering controls. So, this leaves vapor intrusion as the exposure pathway with the greatest potential.
Don’t fear the vapor (queue Blue Oyster Cult soundtrack).
An always-changing vapor intrusion industry
The science of characterizing chemical vapor intrusion pathways continues to evolve. However, the science behind mitigating intrusion has been underway since the residential radon industry originated almost 40 years ago.
Today, this already mature industry continues to evolve. This is demonstrated by the national consensus standards promulgated by the American Association of Radon Scientists and Technologists (AARST) through the American National Standards Institute (ANSI).
These standards are our guide as to the methods of radon and soil gas mitigation in single-family homes (SGM-SF-2017), multi-family buildings (RMS-MF-2018), large building/schools (RMS-LB-2018), and in New Construction (CC-1000-2018). They give a great deal of detail on how to design, install, and verify performance of soil gas mitigation systems to protect the building occupants.
Don’t fear the vapor.
Environmental risk and liability
A recent article regarding California updates to vapor intrusion screening criteria identified the criteria as impeding Brownfield redevelopment of contaminated areas. While potential vapor intrusion should be addressed in Brownfield redevelopment, it does not need to prevent it from happening.
Under the 2001 Brownfield Amendments to CERCLA, a bona fide protective purchaser (BFPP) is shielded from liability for cleaning up historical contamination. This makes Brownfield redevelopments financially feasible. The BFPP provision does require the purchaser to exercise appropriate care to limit continued human exposure.
Administrative controls on contaminated soil (soil management plan) and groundwater (usage restriction) are typical “due care” acts to protect exposure to these media. This is assuming significant off-site contamination migration has occurred.
So, this leaves the vapor inhalation exposure pathway. While mitigating vapor intrusion has financial implications, it generally pales in comparison to measures required to control off-site migration of groundwater or excavation/disposal of contaminated groundwater. This makes vapor intrusion the most manageable exposure pathway.
Don’t fear the vapor.
Better environmental risk management is possible
Once a vapor mitigation solution is in place, due care of operation, maintenance, and monitoring (OM&M) is needed to make sure the system continues to protect building occupants.
The Vapor Sentinel Remote Monitoring (VSRM) system greatly simplifies this OM&M by providing 24/7/365 monitoring of system performance. The monitoring system immediately notifies stakeholders of a problem with the system (e.g. building maintenance, building tenants, regulators, etc.).
The VSRM user interface is customizable to each stakeholder. It provides only the information needed for their role. In addition to current performance data, the system also provides historical performance data. Historical data can be critical evidence for legally defending that occupants were, are, and will be continuously protected against exposure to hazardous soil gases.
With Vapor Sentinel Remote Monitoring keeping watch, there is no need to worry about risks of vapor intrusion. Vapor Sentinel makes it possible to move redevelopment projects forward while satisfying standard requirements and protecting building occupants around the clock.
Don’t fear the vapor.
