Characterizing an off-site release as a Recognized Environmental Condition during a Phase 1 Environmental Site Assessment (ESA) has never sat well with me simply because in 19 years of practice I have yet to do a major environmental cleanup where a regulator was forcing a totally innocent property owner to cleanup his neighbor’s mess.
Now I have had a dozen or more instances where a client has experienced expense as a result of the neighbor’s release. These instances fall into five categories:
- Comingled Plume: the subject property has had a release to the soil/groundwater and the plumes have become comingled—in this instance, a regulator may make the property owner cleanup a lot of the neighbor’s mess;
- Development: the client is developing the site and must remove soil or groundwater that has been impacted as a result of the neighbor’s release migrating on-site;
- Vapor Encroachment: the release of a volatile organic compound has migrated on-site and represents a vapor encroachment condition;
- Dewatering: the subject site is dewatering a subterranean parking garage and unknowingly pumping contaminated groundwater into the sewer system; and
- Private Water Supply: the subject site has a groundwater supply well that has been impacted by the off-site contamination, and the owner must either abandon the well or filter the contaminants.
While the five scenarios presented above are all serious, we can often eliminate 4 of these quickly: often the client does not plan to develop, there is no reason to suspect an on-site release, there is no on-site dewatering system, and drinking wells are usually deep enough to avoid impact from off-site contamination (provided you can document the well depth and have good information regarding the extent and migration of the off-site plume).
That leaves Vapor Encroachment as the primary reason to consider an off-site release a Recognized Environmental Condition in a Phase 1 Environmental Site Assessment. A large up-gradient release can migrate in vapor phase or through ground water and create a vapor intrusion condition. Vapors can migrate up from groundwater, through the soil column, and into the subject property building. After 15 years of soil vapor sampling this phenomena is well proven and not all that uncommon.
What is uncommon is a real estate owner being forced to write big checks on account of this condition. First, most real estate owners are not that proactive when it comes to vapor encroachment. Second, vapor encroachment conditions can often be mitigated relatively affordably—at least compared to soil and groundwater remediation. I agree that a vapor encroachment condition is a recognized environmental condition; however, these off-site issues are certainly a lesser concern than an on-site issue.