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material-balance study

material-balance study
confidential client
eastern United States

Barr was retained by a confidential client to develop and perform material-balance studies for multiple manufacturing processes that use perfluorooctanoic acid (PFOA), a perfluoroalkyl substance (PFAS).

PFOA has been detected in human blood samples even in the world’s most remote locations, and the fate of PFAS used in manufacturing processes had become a subject of interest to the U.S. Environmental Protection Agency.

We worked with a team of collaborators to develop the study protocol and respond to EPA review comments. In addition, Barr participated in several status meetings in Washington, D.C. The meetings included more than a dozen representatives of the EPA and numerous other stakeholders, and we presented reports on study progress, responded to technical inquiries, and forecasted future activities.

As part of the study, Barr performed pre-sampling site visits and developed sampling and analysis plans for each manufacturing process to quantify the PFOA discharged by more than a dozen manufacturing processes. Samples were collected from waste, wastewater, and air-emission streams.

Stack-testing activities were a major component of the study. The EPA had no established test methods for sampling PFOA in air, so Barr collaborated with industry representatives to develop modifications to EPA Method 5 for the quantification of particulate and vapor-phase PFOA. Accepted by the EPA, the approach is now used and referenced by the entire U.S. dispersion-processing industry. In addition, some manufacturing processes required the simultaneous testing of multiple sources to complete the material balance, which required that Barr mobilize multiple test teams throughout the U.S.

manufacturing PFAS