Below is the uncorrected machine-read text of this chapter, intended to provide our own search engines and external engines with highly rich, chapter-representative searchable text of each book. Because it is UNCORRECTED material, please consider the following text as a useful but insufficient proxy for the authoritative book pages.
25 3.1 Overview The research methodology for ACRP Project 02-60 was developed based on the following understanding: â¢ The level of awareness and knowledge associated with AFFF and PFASs varies greatly among (and within) airports. â¢ Management practices associated with AFFF procurement, storage, application, and disposal vary greatly among airports. â¢ Despite PFASs being characterized as an âemerging contaminant,â there has been much study and research on the effects associated with PFASs in the environment. â¢ Regulations associated with PFASs in the environment are being promulgated more frequently and becoming more stringent. â¢ Manufacturers of AFFF have changed their formulations in response to regulatory requirements due to concerns associated with the environmental effects of PFASs in the environment. Most notably, manufacturers have removed PFOS-based AFFF and then PFOA and other âlong-chainâ PFASs from their formulations. â¢ Many airports that have identified issues related to PFASs that are associated with AFFF use or release are unsure of how best to respond, and some have been pursuing guidance on how to manage their liabilities (understanding that regulatory action could potentially lead to expensive assessment and remediation programs). â¢ Effective, state-of-the-practice sampling and laboratory analytical approaches for PFASs have been developed and adopted by federal government departments in both the United States and Canada. â¢ Traditional remediation approaches (e.g., âexcavation and disposalâ and âpump and treatâ) have been successfully applied in the field, but are typically limited in their effectiveness (or cost-effectiveness) to address the impacts of PFASs. The research plan included three principal data-gathering approaches: literature review, air- port survey, and consultation with subject matter and industry experts. The following sections summarize the research methodology associated with each of these approaches. 3.2 Literature Review A literature review was conducted of peer-reviewed (e.g., scientific journal articles) and non-peer-reviewed research (e.g., industry articles) available via academic search engines, online references and searches, and documents otherwise available to the research team. Recognizing that new findings regarding environmental fate and transport and remediation of PFASs are being published at an accelerated rate (10, 55â61), the research team monitored scientific journals C h a p t e r 3 Research Methodology
26 Use and potential Impacts of aFFF Containing pFaSs at airports and industry publications throughout the research. In addition, the research team identified other resources (e.g., conference proceedings) by attending conferences with key subject matter topics, including AFFF, firefighting, PFASs, AFFF alternatives, analysis of PFASs, and remediation technologies for PFASs. Specific efforts targeted jurisdictions that have been relatively (i.e., com- pared to North America) proactiveâsuch as Norway, Sweden, and Australiaâin understanding the chemistry and fate and transport of PFASs and in developing remediation solutions and AFFF alternatives. 3.3 Airport Survey A survey was designed to effectively canvas a broad segment of the North American civilian airports that are required to have firefighting equipment (and, thus, use AFFF) to understand how these airports manage the procurement, storage, use, and disposal of AFFF, and any practices related to impacts of PFASs on the environment. Pursuant to Title 14, Code of Federal Regulations Part 139 (i.e., specifically, Part 139 Airport Certification Status List) and the Canadian Aviation Regulations (CARs) 303, 580 airports (540 airports in the United States and 40 in Canada, including commercial service and general aviation airports) were identified to provide a representative, initial sample population pool that included a broad range of firefighting and emergency response services, management practices, and airport classes. In order to provide a 95-percent confidence level with a margin of error of +/- 5 percent, a net survey sample size of 223 was targeted. Designed to place an emphasis on airports with greater aircraft rescue and firefighting (ARFF) facilities (e.g., larger storage require- ments, more infrastructure and, therefore, it is assumed, more need and use of AFFF), the net sample set included all of the airports in ARFF Categories E, D, and C (including the Canadian airports, which were recategorized to âmatchâ their U.S. category counterparts) and proportional numbers from Categories B and A to produce a total net sample set of 225 airports (199 U.S. airports and 26 Canadian airports). General aviation airports that elected to apply for a Part 139 certificate and thus are required to provide firefighting capabilities pursuant to their Part 139 certification (and were listed on the Part 139 Airport Certification Status List) were categorized among the ARFF indices as appropriate. As detailed in Appendix A of this report, 167 airports across the United States (149) and Canada (18) completed survey interviews between December 2015 and March 2016. The survey questionnaire was vetted by select airports and the ACRP Project 02-60 panel and contained 42 questions, 16 of which were open-ended; the average interview length was 21 minutes. As indi- cated in Table 3-1, the overall response rate was 74 percent, and all ARFF categories had response Category A 48 40 83 Category B 29 22 76 Category C 90 69 77 Category D 28 19 68 Category E 30 17 57 Total 225 167 74 Unduplicated Valid Sample Completed Interviews Percent of Sample Table 3-1. Distribution of responses by airport size category.
research Methodology 27 rates greater than 50 percent. The margin of error for the survey, given the population and sample sizes, is Â± 6.7 percent at the 95-percent confidence level. Data collected from the survey (including open-ended answers) were coded (as detailed in Attachment B of Appendix A) and used to assess the extent of AFFF management and use across a statistically representative cross-section of civilian airports and identify current industry management practices. 3.4 Subject Matter and Industry Expert Outreach To supplement the information on current AFFF management practices obtained through the industry survey, the research team also solicited subject matter and industry expertise related to AFFF; airport firefighting and ARFF classification; regulations associated with PFASs; environ- mental fate, transport, and remediation of PFASs; and laboratory analyses of PFASs. Specifically, the research team reached out to manufacturers of AFFF and alternative products; industry trade organizations; airports, including airport emergency response personnel; academics specializing in the science of PFASs; commercial analytical laboratories; and representatives of government involved in the regulation of PFASs and policy development. The research also sought input from the ACRP Project 02-60 panel. Additionally, the screening tool framework was reviewed by the ACRP Project 02-60 panel, and subsequent beta testing of the screening tool was vetted by three airports.