Today ASTM published the long awaited final E 2600 - 08 Standard Practice for Assessment of Vapor Intrusion into Structures on Property Involved in Real Estate Transactions. The standard is intended to be used to conduct vapor intrusion assessments on properties involved in real estate transactions and may be used as a voluntary supplement to a Standard Practice E 1527 Phase 1 Environmental Assessment. The vapor intrusion standard was specifically designed to complement existing state and federal vapor intrusion policy and guidance.

The vapor intrusion standard has been in development for over two years by a broad based ASTM task group made up of consultants, regulators, lawyers, and industry representatives. Dave Folkes of EnviroGroup was co-chair of the committee responsible for developing the tier structure for the evaluation process. Please do not hesitate to contact us if you would like to discuss how the new vapor intrusion standard may affect your business or property.

The standard may be purchased from ASTM at:

In summary, the standard uses a tiered approach involving:

Tier 1 -Non Numeric Screening

A site can be screened out in Tier 1 if a record search (based on ASTM E 1527 Phase 1 records) indicates that there are no sources of contaminants of concerns (e.g., volatile organic compounds) within certain search distances of the subject property (including upgradient and cross-gradient directions).

Tier 2 - Numeric Screening

If vapor intrusion is not eliminated as a pathway of concern in Tier 1, existing or newly collected soil, soil gas or groundwater data may be used in Tier 2 to screen the property using generic risk based concentrations from the appropriate regulatory agency. If a vapor intrusion condition cannot be screened out using these data, then a user may proceed to a Tier 3 evaluation. An alternative to Tier 3 is to proceed directly to mitigation.

Tier 3 - Site Specific Screening

If vapor intrusion is not eliminated as a pathway of concern in Tier 2, a vapor intrusion investigation following relevant regulatory agency guidance or requirements may be implemented in Tier 3. Investigations can include groundwater, soil gas, sub- slab soil gas, or indoor air, depending on agency requirements.

Tier 4 - Vapor Intrusion Mitigation

The E 2600-08 standard also includes a section on vapor intrusion mitigation. Topics covered include institutional controls, engineering controls, and intrinsically safe building design.

Appendices

There are nine appendices to the standard including a list of typical chemicals of concern for vapor intrusion, web links to state and EPA vapor intrusion guidance and requirements, and a questionnaire which can be used to gather the necessary information.