How to comply with the vapor encroachment assessment required by ASTM Standard E1527-13 (ASTM E1527-13) has become a common question for Phase I Environmental Site Assessment users in search of satisfying the CERCLA all appropriate inquiry rules.   As we reported in our prior frESH law blog post, unlike ASTM Standard E1527-05, the new ASTM E1527-13 specifically requires assessing the potential for hazardous vapors to migrate onto or within the target property.  It does so by defining “migrate/migration” as “the movement of hazardous substances or petroleum products in any form, including, for example, solid and liquid at the surface or subsurface, and vapor in the subsurface,”  and then requiring an analysis of surrounding property uses and data-base records for migration potential.  

ASTM E1527-13 provides no other instruction on how to assess vapor encroachment or when a more in-depth look at vapor encroachment is warranted.  This is where ASTM Standard E2600-10 Standard Guide for Vapor Encroachment Screening on Property Involved in Real Estate Transactions (Guide 2600) comes in.  A footnote to the definition of “migrate/migration” in ASTM E1527-13 states “vapor migration in the subsurface is described in Guide 2600,” thereby placing some reliance on Guide 2600.  Further, the goal of Guide 2600 is to identify a Vapor Encroachment Condition, or VEC, which is “the presence or likely presence of [chemicals of concern] vapors in the sub-surface of the target property (TP) caused by the release of vapors from contaminated soil or groundwater either on or near the TP as identified by Tier 1 … or Tier 2 … procedures.”  Similarly, the goal of ASTM E1527-13 is to identify a Recognized Environmental Condition, or REC, which is “the presence or likely presence of any substances or petroleum products in, on, or at a property… due to release to the environment… .” 

ASTM E1527-13 and Guide 2600 not only have similar goals, but also similar due diligence processes.  Guide 2600 specifies use of “Phase I ESA-type information to determine if a VEC exists” as part of a “Tier 1” screen.  This includes an analysis of historical records, historical uses, federal, state, local and tribal governmental records, physical setting information and user-specialized knowledge.   The Tier 1 screen even uses minimum search distances, focusing its analysis on potential petroleum releases within 1/10 of a mile from the target property, and up to 1/3 of a mile for hazardous material releases that migrate more easily than petroleum.  Unless a Tier 1 screen can rule out a VEC, Guide 2600 calls for regulatory file reviews and/or soil, soil gas or groundwater sampling under a Tier 2 screen process, similar to what occurs if a REC is identified under ASTM E1527-13. 

With ASTM E1527-13 specifically referencing Guide 2600 to define “vapor migration,” and the strong overlap in the assessment procedures to identify a REC and a VEC, a Phase I user would be wise to order a Tier 1 vapor screen under Guide 2600 as part of a Phase I ESA to help ensure the all appropriate inquiry standards are met.  This process should not add material cost since much of the ASTM E1527-13 information can be used to make a VEC conclusion.  In practice, many consultants currently reference having conducted the ASTM E1527-13 vapor analysis using a Tier 1 screen, even if not specified in the scope of work.   

ASTM E1527-13 takes some pressure off by stating “nothing in this practice should be construed to require application of the Guide E2600 standard to achieve compliance with all appropriate inquiries.”  In the absence of other definitive and widely-accepted guidance, though, using Guide E2600 for the ASTM E1527-13 vapor encroachment assessment is a safe and relatively easy bet.