The U.S. Environmental Protection Agency’s interim best practices guidelines for the removal and destruction of per- and polyfluoroalkyl substances, often described as “forever” chemicals, highlight several technologies already widely used, but others, especially those focused specifically on destruction, are more nascent, according to several water industry sources interviewed by ENR.
The EPA released the updated guidance last month to reflect the most recent data available on both separation and destruction technologies that are effective in reducing levels of the chemicals, called PFASs, in water, wastewater and manufactured products that enter human tissue. PFAS chemicals are known to cause health problems, including damage to fetal development, as well as liver, immune and thyroid conditions.
The guidance does not impose new requirements, but is designed to provide states, utilities, waste managers and local communities with the information they need to make decisions about how to manage chemicals safely and protect human health, EPA officials said.
“This updated guidance identifies approaches to managing PFAS waste using the best available gold standard science, so communities across the country can be confident that these chemicals are managed, disposed of and destroyed in ways that safeguard their health and the environment,” EPA Administrator Lee Zeldin said in a statement.
The guide highlights three types of technologies to remove or destroy the substances: underground injection, landfills and a range of heat treatments, including incineration and more innovative technologies to break the carbon-fluorine bond.
“I think the important thing about the guidelines is that they don’t recommend a specific technology. It’s still an emerging challenge for the water sector to deal with the fact that being too prescriptive in technology still doesn’t make sense,” said John Ikeda, chief mission officer at the Water Environment Foundation, adding that the guidelines point out that more research is needed.
According to the EPA, more information is needed to understand whether harmful byproducts of incomplete combustion or air emissions of PFAS are formed by units operating at lower temperatures, such as municipal waste incinerators.
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EPA’s action follows the release of a guidance note earlier this year by the US Department of Defense on the removal and destruction of PFAS at its facilities across the country.
Both papers “speak to the fact that big conversations are happening and need to be had about what are the best ways to handle these materials,” said Chris Higgins, executive director of a newly established research center to evaluate different PFAS destruction technologies at the Colorado School of Mines in Golden, Colo.
While the handful of large federal settlements with PFAS makers like 3M and DuPont will fund removal and destruction projects, the actual cleanup work in most of those cases is not yet imminent, Higgins said, although “a lot of places are being looked at and they’re doing their remedial research and figuring out what makes the most sense in terms of what to do.”
Local officials are often unsure which technologies make the most sense for their own municipalities and whether they should be fixed at all, said Leon Downing, director of innovation and research at Black & Veatch, which has conducted several studies comparing the benefits and drawbacks of different technologies.
“A lot of PFAS removal and destruction technologies are quite intensive from a capital standpoint and from an operational requirements standpoint. So we’re just starting to understand how we might do that and decide if there’s enough driver … to do that.” he said
Treatment options range from membranes, pyrolysis, gasification and supercritical water oxidation of biosolids streams, Downing said. “There are options out there, and the challenge becomes, ‘Okay, destroy PFAs, but it takes a very large amount of energy to do that, so where’s the overall balance of environmental impact?’
EPA is accepting public comments until June 29.
