As indicated in a recent post, ASTM International has developed a revision of the Phase I protocol, Standard Practice for Environmental Assessments: Phase I Environmental Site Assessment Process ("E 1527‑05") that will be issued this year.
A topic being heatedly discussed, especially by consultants, is whether the revised E 1527 will require vapor intrusion evaluation or a vapor encroachment analysis under ASTM's E 2600-10, Standard Guide for Vapor Encroachment Screening on Property Involved in Real Estate Transactions. The answer on both accounts is "no."
A better question is whether the significant scientific and regulatory developments related to vapor migration and intrusion in many jurisdictions should already be informing professional judgments of environmental professionals performing Phase I environmental site assessments under the existing E 1527-05. The answer to this question, in my view, is "yes."
Vapor intrusion evaluations are well beyond the level of information and analysis that takes place in a Phase I. Speculating about whether chemical vapors are entering buildings should not be part of a Phase I report. This is the reason that ASTM's E 2600-08, Standard Practice for Vapor Intrusion Assessment (which used Phase I-type information to presume that vapor intrusion was occurring at a target property) needed to be thrown out.
ASTM's replacement document, the E 2600-10 Standard Guide for Vapor Encroachment is purposefully not a Standard Practice. The E 2600-10 Guide itself expressly states that it is not part of all appropriate inquiries or of the performance of a Phase I under E 1527-05. I was a primary author of the Legal Appendix published with E 2600-10. Why I was involved in the process, and yet don't recommend E 2600-10 to clients, is a separate topic that relates to strong resistance to withdrawing E 2600-08 without a replacement document, and, for example, the fact that search distances in E 2600-10 don't meet the requirements of E 1527-05.
On the other hand, there is nothing in the existing E 1527-05 (or coming in the revision) that carves the presence of hazardous substances in vapor form out of the definition of a recognized environmental condition ("REC") (nor anything that carves vapors out of the scope of AAI or CERCLA jurisdiction). The growing understanding of how volatile chemicals move in the subsurface should inform environmental professionals' judgments about whether hazardous substances are likely present at a target property in making Phase I REC determinations; the developing science, regulations and guidance on vapor intrusion may need to be considered by the environmental professional when he or she determines whether the presence of a volatile chemical in the subsurface of the property can be considered de minimis.
Having said all of this, when an environmental professional has determined that volatiles are likely present at the target property in the groundwater (or soil) above de minimis levels, that condition is the REC, and there is no justification or need for the environmental professional to speculate further about the vapor pathway in the Phase I report. Evaluation of that pathway is beyond Phase I, as is complete delineation of the extent of any other REC.
To me, it seems that it should be a rare case where a consultant can, on Phase I type information, support a determination that a hazardous volatile is likely present in soil gas of the target above de minimis levels based solely on vapor movement (independent of groundwater movement) from an offsite release. In other words, the 'vapor only' REC is theoretically possible, but should be practically rare, and nothing in AAI or E 1527-05 justifies speculation or requires sampling.
Because there is and will continue to be confusion on this topic, it is important to make sure that you are on the same page with any consultant you hire for a Phase I, especially for brownfield properties. Note especially that a consultant who inserts a statement disclaiming any consideration of vapors in the Phase I assessment may generate a Phase I report that does not satisfy all appropriate inquiries.
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