The objective of this Statement of Need was to develop standard operating protocols to assess the potential for leaching and mobility of per and polyfluoroalkyl substances (PFAS) from solids, soils, and sediments (collectively referred to as “solids”). Rapid, accurate, and reproducible characterization of PFAS in solids was needed to aid in the screening, geochemical assessment, and disposal requirements of PFAS and PFAS-impacted materials at military installations. Specific objectives were:

• Development of a standardized method, similar to the Synthetic Precipitation Leaching Procedure (SW-846 Method 1312), to assess the leachability and mobility of PFAS from solid matrices. Solids may include solid waste, concrete, biosolids, emergency response wastes, and other materials of commerce.
• Development of new or improved methods to evaluate sorption/desorption affinity of PFAS for specific solid materials of concern to the Department of Defense (e.g., concrete, soils, construction debris, sediments).

The proposed methods should have been able to provide repeatable and environmentally relevant measures of PFAS. The focus of this work should have been for at least the USEPA 24 PFAS as shown in Table 1. Proposals should have addressed one or more of the objectives listed above.

Successful proposals were highly focused and showed direct relevance to support decision-making for site investigation, source zone control, and possible stabilization/soil washing types of technologies. Methods developed should have produced appropriate quantitation limits and report concentrations relative to the media sampled (e.g., ng/L) considering the EPA drinking water Health Advisory Levels for perfluorooctane sulfonate and perfluorooctanoic acid and relevant Federal and State regulations. Method development must have followed the EPA’s method validation and peer review policies and guidelines (EPA 2016) and resulted in a written method that follows the EPA SW-846 method style guide (EPA 2012). The analytical methods used in testing the leaching method must meet the requirements for PFAS analysis in the Department of Defense Quality Systems Manual for Environmental Laboratories (QSM 5.1).

Funded projects will appear below as project overviews are posted to the website.

Addressing the research objectives described above will meet a critical need to support the development of site-specific assessments of PFAS leachability to water, as well as support remedial design and waste disposal of PFAS-containing solids at DoD sites. This will in turn lead to improved management of PFAS sites by facilitating more accurate and precise assessments of the extent of PFAS contamination.

PFAS are present in AFFF used by the DoD and other organizations to extinguish hydrocarbon fires. Different AFFF formulations have been used, but all contain a complex mixture of PFAS, including those of greatest regulatory concern - the PFAAs and potential PFAA precursors (Field et al., 2017; ITRC, 2017). EPA has recommended a Health Advisory Level for perfluorooctanoic acid (PFOA) and PFOS, and several states have promulgated standards for PFOA, PFOS, and some of the related PFAAs (ITRC, 2018a).

SERDP has been funding research on AFFF contamination for several years to improve PFAS analysis, to develop tools for assessing the fate of PFAS in the subsurface, and to evaluate the potential for in situ remediation. A recent SERDP & ESTCP-sponsored workshop identified a number of research needs, and proposers should view the Workshop Report to obtain additional detail concerning these discussions. PFOS is of particular concern to DoD, as it is the predominant PFAS in some AFFF formulations, and a significant dead-end metabolite in others, and therefore it is typically the predominant PFAS in AFFF-impacted groundwaters (Anderson et al., 2016). PFOS appears to be particularly resistant to destructive technologies, and like the rest of the PFAAs it is generally considered nonbiodegradable (ITRC, 2018b).

The military services are in need of methodologies to assess PFAS in solids, soils and sediments. Solids may include solid waste, concrete, biosolids, emergency response wastes, and other materials of commerce as well as soils and sediments. Currently, no single document or source exists for these procedures.

The cost and time to meet the requirements of this SON are at the discretion of the proposer. Two options are available:

Standard Proposals: These proposals describe a complete research effort. The proposer should incorporate the appropriate time, schedule, and cost requirements to accomplish the scope of work proposed. SERDP projects normally run from two to five years in length and vary considerably in cost consistent with the scope of the effort.

Limited Scope Proposals: Proposers with innovative approaches to the SON that entail high technical risk or have minimal supporting data may submit a Limited Scope Proposal for funding up to $200,000 and approximately one year in duration. Such proposals may be eligible for followon funding if they result in a successful initial project. The objective of these proposals should be to acquire the data necessary to demonstrate proof-of-concept or reduction of risk that will lead to development of a future Standard Proposal. Proposers should submit Limited Scope Proposals in accordance with the SERDP Core Solicitation instructions and deadlines.