Uses—This practice is intended for use on a voluntary basis by parties who wish to conduct a VIA on a parcel of real estate, or more specifically conduct a screening evaluation to determine whether or not there is potential for a VIC, and if so, identify alternatives for further investigation. To determine whether the vapor intrusion exposure pathway is complete and, if so, whether it poses or may pose an unacceptable risk to human health (that is, whether a VIC exists), this practice directs the user and environmental professional to existing federal or state vapor intrusion policy, regulation and guidance (refer to Appendix X5 and Appendix X9). The process defined in this practice begins with a reasonably conservative screening process that requires information generally collected as part of a Practice E 1527 Phase I ESA. If a pVIC is identified in this initial screening, the process gradually progresses toward a more complex assessment involving increasingly greater use of site-specific data. For those sites unable to be screened out, the process provides alternative methods to determine whether a VIC exists. If a VIC is found to exist, the process describes general mitigation alternatives. This practice is intended primarily as an approach to conducting an inquiry designed to identify pVICs or VICs in connection with a property involved in a real estate transaction. This practice is intended to reflect a commercially practical and reasonable inquiry (see 1.2). The practice can be applied to property with existing structures, property with structures that will be substantially rehabilitated, property without existing structures but having planned structures (for example, property in development), or property without existing structures and with no planned structures (for example, undeveloped property with no planned development).

Clarifications on Use:

Use in Conjunction with Practice E 1527 Phase I ESA—This practice, when added as a supplemental scope of work to a Practice E 1527 Phase I ESA, is designed to assist the user and environmental professional in developing information about pVICs or VICs associated with a target property and, as such, has utility for a wide range of persons, including those who may not be involved in a real estate transaction.

Independent Use—This practice may also be used independently of any other property environmental assessment to determine if a pVIC or VIC exists. However, prior to use the user and environmental professional should be familiar with the data collection requirements associated with a Practice E 1527 Phase I ESA that are referenced in this practice (see 5.3).

Site-Specific—This practice is property-specific in that it relates to assessment of pVICs or VICs in existing structures or planned structures on a specific parcel of real estate. Consequently, this practice does not address many additional issues raised in transactions such as purchases of business entities or interests therein, or of their assets, that may well involve environmental liabilities pertaining to properties previously owned or operated or other off-site environmental liabilities. The practice is not intended to replace a Phase I ESA conducted by an environmental professional, but rather to supplement it.

Who May Conduct—A VIA shall be performed by an environmental professional as specified in 7.5.1 and Practice E 1527. No practical standard can be designed to eliminate the role of professional judgment and the value and need for experience in the party performing the inquiry. The professional judgment of an environmental professional is, consequently, vital to the performance of this assessment.

Additional Services—As set forth in Section 13, additional services may be contracted for between the user and the environmental professional. Such additional services may include business environmental risk issues not included within the scope of this practice, examples of which are identified in 13.3.

Principles—The following principles are an integral part of this practice and are intended to be referred to in resolving any ambiguity or exercising such discretion as is accorded the user or environmental professional in performing a VIA.

Uncertainty Not Eliminated in Screening—No vapor intrusion screen, such as included in Sections 8 and 9 of this practice, can wholly eliminate uncertainty regarding the potential for identifying VICs in connection with a target property. Screening is intended to reduce, but not eliminate, uncertainty regarding the potential for a VIC to exist in connection with a property.

Not Exhaustive—The practice is not meant to be an exhaustive assessment. There is a point at which the cost of information obtained or the time required to gather it outweighs the usefulness of the information and, in fact, may be a material detriment to the orderly completion of real estate transactions. One of the purposes of this practice is to identify a balance between the competing goals of limiting the costs and time demands inherent in performing a VIA and the reduction of uncertainty about unknown conditions resulting from additional information.

Level of Inquiry is Variable—Not every property will warrant the same level of assessment. Consistent with good commercial or customary practice, the appropriate level of assessment will be guided by the type of property subject to assessment, the risk tolerance of the user, and the information already available or developed in the course of the inquiry.

Comparison with Subsequent Inquiry—It should not be concluded or assumed that an inquiry was not adequate because the inquiry did not identify pVICs or VICs in connection with a property. The VIA must be evaluated based on the reasonableness of judgments made at the time and under the circumstances in which they were made. Subsequent VIAs should not be considered valid standards to judge the appropriateness of any prior assessment based on hindsight, new information, use of developing technology or analytical techniques, or other factors.

Continued Viability of VIA—Subject to 4.7, a VIA meeting or exceeding this practice and completed less than 180 days prior to the date of acquisition of the property (EPA, under “All Appropriate Inquiry,” 40 C.F.R. Part 312, defines date of acquisition as the date on which a person acquires title to the property), or (for transactions not involving an acquisition) the date of the intended use of the VIA, is presumed to be valid. If within this period the assessment will be used by a different user than the user for whom the assessment was originally prepared, the subsequent user must also satisfy the User’s Responsibilities in Section 6. Subject to 4.7 and the User’s Responsibilities set forth in Section 6, a VIA meeting or exceeding this practice and for which the information was collected or updated within 1 year prior to the date of acquisition of the property or (for transactions not involving an acquisition) the date of the intended use of the VIA may be used provided that the following components of the inquiries were conducted or updated within 180 days of the date of purchase or the date of the intended transaction:

Reviews of federal, tribal, state, and local government records;

Update on the operations existing at the target property;

Evaluation of any new significant potential preferential pathways for vapor migration;

Assessment of any new plume migration that can potentially cause a pVIC or VIC on the target property; and

Assessment of any new contaminant releases in the area of concern that can potentially cause a pVIC or VIC on the target property.

Prior Assessment Usage—This practice recognizes that VIAs performed in accordance with this practice will include information that subsequent users may want to use to avoid undertaking duplicative assessment procedures. Therefore, this practice describes procedures to be followed to assist users in determining the appropriateness of using information in VIAs performed more than one year prior to the date of acquisition of the property or (for transactions not involving an acquisition) the date of the intended use of the VIA. The system of prior assessment usage is based on the following principles that should be adhered to in addition to the specific procedures set forth elsewhere in this practice:

Use of Prior Information—Subject to the requirements set forth in 4.6, users and environmental professionals may use information in prior VIAs provided such information was generated as a result of procedures that meet or exceed the requirements of this practice. However, such information shall not be used without current investigation of conditions likely to affect pVICs or VICs in connection with the target property. Additional tasks may be necessary to document conditions that may have changed materially since the prior VIA was conducted.

Contractual Issues Regarding Prior Assessment Usage—The contractual and legal obligations between prior and subsequent users of VIAs or between environmental professionals who conducted prior VIAs and those who would like to use such prior VIAs are beyond the scope of this practice.

Actual Knowledge Exception—If the user or environmental professional conducting a VIA has actual knowledge that the information being used from a prior VIA is not accurate or if it is obvious, based on other information obtained by means of a Phase I and/or Phase II ESA or known to the person conducting the Phase I and/or Phase II ESA, that the information being used is not accurate, such information from a prior VIA may not be used.

Rules of Engagement—The contractual and legal obligations between an environmental professional and a user (and other parties, if any) are outside the scope of this practice. No specific legal relationship between the environmental professional and the user is necessary for the user to meet the requirements of this practice.

1.1 Purpose—The purpose of this practice is to define good commercial and customary practice in the United States of America for conducting a vapor intrusion assessment (VIA) on a property parcel involved in a real estate transaction with respect to chemicals of concern (COC) that may migrate as vapors into existing or planned structures on a property due to contaminated soil and groundwater on the property or within close proximity to the property. This practice may be used as a voluntary supplement to Practice E 1527 and does not alter or in any way define the scope of that practice. In addition, performance of this standard is not a requirement of and does not constitute, expand, or in any way define “all appropriate inquiry” as defined or approved by U.S. EPA under CERCLA and the regulations thereunder, including 40 CFR Sec. 312.11.

1.1.1 Vapor Intrusion Condition (VIC)—In defining a standard of good commercial and customary practice for conducting a VIA on a parcel of property, the goal of the process established by this practice is to identify whether or not a vapor intrusion condition (VIC) exists or is likely to exist on the property. The term VIC means the presence or likely presence of any COC in the indoor air environment of existing or planned structures on a property caused by the release of vapor from contaminated soil or groundwater either on the property or within close proximity to the property, at a concentration that presents or may present an unacceptable health risk to occupants. The term is not intended to include de minimis conditions that do not normally represent an unacceptable health risk to occupants and that generally would not be the subject of an enforcement action if brought to the attention of appropriate governmental agencies. A condition determined to be de minimis does not represent a VIC.

1.1.2 Other Federal, State, and Local Environmental Laws—This practice does not address requirements of any federal, state, or local laws with respect to vapor intrusion. Users are cautioned that federal, state, and local laws, regulations or policy may impose VIA obligations that are beyond the scope of this practice (refer to Appendix X5 and Appendix X9). Users should also be aware that there are likely to be other legal obligations, for example, disclosure, with regard to COC discovered on the property that are not addressed in this practice and that may pose risks of civil or criminal liability, or both.

1.1.3 Documentation—The scope of this practice includes investigation and reporting requirements. Sufficient documentation of all sources, records, and resources used in the inquiry required by this practice shall be provided in the report (refer to Section 12).

1.2 Objectives—Objectives guiding the development of this practice are: (1) to synthesize and put into writing good commercial and customary practice for conducting a VIA on a property involved in a real estate transaction, (2) to supplement a Phase I environmental site assessment (ESA) conducted in accordance with Practice E 1527, (3) to ensure that the process for assessing vapor intrusion is practical and reasonable, and (4) to provide an industry standard for a VIA on a property involved in a real estate transaction.

1.3 Considerations Beyond Scope—The use of this practice is strictly limited to the scope set forth in this section. Section 13 of this practice identifies, for informational purposes, certain tasks (not an all-inclusive list) which may be conducted on a property that are beyond the scope of this practice but which may warrant consideration by parties to a real estate transaction. The need to include an investigation of any such conditions in the environmental professional's scope of services should be evaluated based upon, among other factors, the nature of the property and the reasons for performing the site assessment (for example, a more comprehensive evaluation of business environmental risk) and should be agreed upon between the user and environmental professional as additional services beyond the scope of this practice prior to initiation of the Phase I ESA or initiation of an independent VIA.

1.4 Organization of This Practice—This practice has thirteen sections and nine appendices. The appendices are included for informational purposes and are not part of the procedures prescribed in this practice.

1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

1.6 This practice offers a set of instructions for performing one or more specific operations. This document cannot replace education or experience and should be used in conjunction with professional judgment. Not all aspects of this practice may be applicable in all circumstances. This ASTM standard is not intended to represent or replace the standard of care by which the adequacy of a given professional service must be judged, nor should this document be applied without consideration of a project's many unique aspects. The word “Standard” in the title means only that the document has been approved through the ASTM consensus process.