ASTM E2600-15

4.2.1 Use in Conjunction with Practice E1527 Phase I ESA—This guide, when used in conjunction with Practice E1527 Phase I ESA, may assist the user and environmental professional in developing information about VECs associated with a TP. This guide has utility for a wide range of persons, including those who may not be involved in a 4.2.2 Independent Use—This guide may be used independent of a Practice E1527 Phase I ESA to determine if a 4.2.3 Site-Specific—This guide is property specific in that it relates to screening of VECs associated with a specific parcel of 4.3 Who May Conduct—A VES should be performed by an 4.4 Additional Services Contracted For—Additional services may be contracted for between the 4.5 Principles—The following principles are an integral part of this guide and are intended to be referred to in resolving any ambiguity or exercising such discretion as is accorded the 4.5.1 Uncertainty Not Eliminated in Screening—No vapor encroachment screen, such as included in Sections 8 and 9 of this guide, can wholly eliminate uncertainty regarding the identification of VECs in connection with a TP. Screening is intended to reduce, but not eliminate, uncertainty regarding whether or not a VEC exists in connection with a property.

4.5.2 Not Exhaustive—The guide is not meant to be an exhaustive screening. 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 guide is to identify a balance between the competing goals of limiting the costs and time demands inherent in performing a 4.5.3 Level of Investigation is Variable—Not every property will warrant the same level of screening. The appropriate level of screening should be guided by the nature of the property subject to screening and the information already available or developed in the course of the investigation.

4.5.4 Comparison with Subsequent Investigation—It should not be concluded or assumed that an investigation was not adequate because the investigation did not identify 4.6 Continued Viability of VES—Subject to subsection 4.7, a 4.6.1 Reviews of federal, tribal, state, and local government records;

4.6.2 Update on the operations existing at the 4.6.3 Evaluation of any new potential preferential pathways for vapor migration;

4.6.4 Screening of any new contaminated plume migration that might cause a 4.6.5 Screening of any new contaminant releases in the 4.7 Use of a Prior VES Screen—This guide recognizes that VESs performed in accordance with this guide will include information that subsequent users may want to use to avoid undertaking duplicative screening procedures. Therefore, this guide describes procedures to be followed to assist users in determining the appropriateness of using information in VESs 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 4.7.1 Use of Prior Information—Subject to the criteria set forth in subsection 4.6, users and environmental professionals may use information in a prior VES provided such information was generated as a result of procedures that are consistent with the procedures presented in this guide. However, such information should not be used without current investigation of conditions likely to affect VECs in connection with the TP. Additional investigation may be necessary to document conditions that may have changed materially since the prior 4.7.2 Contractual Issues Regarding Use of a Prior VES—The contractual and legal obligations between prior and subsequent 4.8 Actual Knowledge Exception—If the user or environmental professional conducting a 4.9 Rules of Engagement—The contractual and legal obligations between an 1.1 Purpose—The purpose of this guide is to provide practical guidance and a useful process for conducting a 1.1.1 Vapor Encroachment Condition (VEC)—The goal of conducting a VES, as established by this guide, on a parcel of property is to identify a vapor encroachment condition (VEC), which is the presence or likely presence of COC vapors in the vadose zone of the 1.1.2 Federal, State, and Local Environmental Laws—This guide does not address requirements of any federal, state, or local laws with respect to vapor intrusion. 1.1.3 Documentation—The scope of this guide includes investigation and reporting actions. Sufficient documentation of all sources, records, and resources used in the investigation procedures that are set out in this guide should be provided in the 1.2 Objectives—Objectives guiding the development of this guide are: (1) to synthesize and put into writing a practical guide for conducting a VES on a property involved in a 1.3 Considerations Outside the Scope—The use of this guide is strictly limited to the scope set forth in this section. Section 11 of this guide identifies, for informational purposes, certain tasks (not an all-inclusive list) that may be conducted on a property that are beyond the scope of this guide but that may warrant consideration by parties to a 1.4 Units—The values stated in inch-pound units are to be regarded as the standard. The values given in parentheses are mathematical conversions to SI units that are provided for information only and are not considered standard.

1.5 Organization of this Guide—This guide has eleven sections and nine appendices. The appendices are included for informational purposes and are not part of the procedures prescribed in this guide.