1.1 In this guide, practitioners are informed on the considerations relevant to the environmental field sampling component of data acquisition programs for per- and polyfluoroalkyl substances (PFAS).

1.2 In this guide, the collection of environmental media, including potable water (such as drinking water), non-potable water (such as groundwater, surface water, stormwater, and wastewater), solids (such as soil, sediment, and biosolids), biological tissue, and waste are addressed.

1.3 In this guide, collection of air sample matrices (such as ambient air, indoor air, soil gas, or stationary source emissions) are not addressed.

1.4 In this guide it is recognized that PFAS can be polymeric or nonpolymeric, collectively amounting to more than 4700 Chemical Abstracts Service (CAS)-registered substances. Environmental concerns pertaining to PFAS are centered primarily on the perfluoroalkyl acids (PFAA), a subclass of PFAS that display extreme persistence and chain-length-dependent bioaccumulation and adverse effects in humans and biota.

1.5 In this guide, the term PFAS is used in a method-defined context that is dependent on the data resulting from the respective PFAS analytical method, each of which includes a list of target analytes determined by that method or a description of the method-defined analytical parameters.

1.6 In this guide, information is provided to address the challenges inherent in the design and execution of PFAS environmental sampling programs that meet project data quality objectives (DQOs) and regulatory requirements.

1.7 The considerations for the successful planning and execution of the environmental field sampling component of PFAS data acquisition programs, including key decision criteria and best practices to aid users in achieving project objectives, are discussed in this guide.

1.8 In this guide, key factors are considered in the design of PFAS environmental sampling programs such as the increased potential for cross contamination because of the ubiquitous presence of PFAS in commonly used products and materials, the limited body of empirical research on cross contamination, the potential for precursor PFAS compounds to transform in the environment into terminal PFAA compounds, and the low levels of detection (parts per trillion or ppt) for PFAS compounds.

1.9 This guide includes accepted best practices used during environmental field sampling programs that are applicable to PFAS sample collection activities. This guide complements but does not replace existing technical guidance and regulatory requirements. This guide provides a compilation of best practices for the design, planning, and execution of PFAS sample collection programs to assist guide users in navigating the competing, conflicting, or lack of guidance issued by some state and federal agencies.

1.10 In this guide, user-led collaboration is encouraged with stakeholders, including analytical laboratories, data evaluation practitioners, and regulators, in the planning and execution of data acquisition programs to meet project DQOs.

1.11 In this guide, the complexity and diversity of environmental programs and project objectives are recognized and technical support for a range of project applications is provided. The appendix to this guide provides additional information and resources and is not mandatory for the use of this guide.

1.12 ASTM International standard guides are not regulations; they are consensus-based standard guides that may be followed voluntarily.

1.13 Units—The values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematical conversions to SI units that are provided for information only and are not considered standard.

1.14 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, health, and environmental practices and determine the applicability of regulatory limitations prior to use.

1.15 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.