1660317615001 Epaeyesphosphogypsumwastewater

EPA Eyes Stricter Phosphogypsum Rule

April 21, 2021
Petition seeks regulatory action regarding the chemical’s toxicity

In early April, a Florida pond that sits atop phosphogypsum tailings sprung a leak. State authorities scrambled to keep the pond from collapsing and flooding the surrounding area with millions of gallons of contaminated water. This situation likely wasn’t top of mind on February 8, 2021, when a group of environmental protection advocates prepared and submitted to the U.S. Environmental Protection Agency (EPA) a petition under Section 21 of the Toxic Substances Control Act (TSCA). The petition seeks to reverse the EPA’s 1991 “Bevill” regulatory determination excluding phosphogypsum and process wastewater from phosphoric acid production (process wastewater) from hazardous waste regulation under Subtitle C of the Resource Conservation and Recovery Act (RCRA). The timing of the Florida near-catastrophe could not be more ironic.


Section 21 allows any person to petition the EPA for the issuance, amendment, or repeal of a rule under TSCA Section 4, 6, or 8 or an order under TSCA Section 4 or 5(e) or (f). In this case, petitioners requested the EPA initiate TSCA Section 6(b) existing chemical prioritization process to designate phosphogypsum and process wastewater as “high-priority” substances for risk evaluation under TSCA Section 6. Petitioners also requested that EPA issue a TSCA Section 4 test rule for disposed phosphogypsum as well as a significant new use rule (SNUR) under TSCA Section 5 for phosphogypsum used in road construction, effectively prohibiting that use. The EPA has 90 days from the filing date to grant or deny the petition.

According to petitioners, studies have found widespread groundwater contamination at “phosphogypsum stack sites including contaminated off-site wells, the potential for drinking water source exposures, several documented damage cases that impacted both ground and surface waters and threatened and harmed aquatic life, increased air pathway cancer risk for those living near stacks, and varied and inadequate state regulation.” The EPA issued a regulatory determination in 1991 exempting phosphogypsum and process wastewater from Subtitle C hazardous waste regulation. Multiple large-volume releases of phosphoric acid production waste have occurred over the years, causing contamination.

Phosphogypsum wastewater contains heavy metals and naturally occurring radioactive materials. This is one reason the petitioners asked the EPA to ban use of phosphogypsum in road construction. The petition notes the agency’s decision to allow this use “reversed course on its 30+ years of finding that radon from phosphogypsum poses an unacceptable risk to public health if used in road construction.”



Apart from the ongoing risks posed by the Florida incident, the Section 21 petition raises interesting questions regarding whether TSCA Section 21 is the most appropriate or efficient means to address risks. Neither phosphogypsum nor process wastewater is listed on the TSCA Inventory. It’s likely that any commercial use of phosphogypsum is included under the identity of calcium sulfate, in which other components (notably the toxic metals discussed in the petition) are considered impurities. The EPA would thus prioritize calcium sulfate under Section 6, but not all calcium sulfate is from phosphogypsum, and not all calcium sulfate has the impurities of note here. In short, the requested relief sought by the petitioners doesn’t appear to be an easy fix.

Other options exist if the EPA were to go this route. If the agency determined that disposal of phosphoric acid production waste poses an unreasonable risk, it could take action under TSCA to mitigate risks from disposal. In addition, the EPA could employ one or more EPA-administered authorities (e.g., RCRA) if the risk could be eliminated or reduced to a sufficient extent under that authority. The petitioners also seek a TSCA SNUR to prohibit use of phosphogypsum. Given the agency’s prior decision to allow use of phosphogypsum in roadbeds, that use would likely be considered ongoing, in which case the EPA couldn’t issue an SNUR as those apply to “new” uses. In short, RCRA is perhaps a more-effective mechanism for addressing the risks identified in the petition.

The petition is yet another example of the increasing perceived utility of TSCA as a potent tool to address chemical risks. It may not be the best tool for all situations, but we can expect to see more Section 21 petitions in our future, and some interesting legal theories supporting their application.

LYNN L. BERGESON is Chemical Processing's Regulatory Editor. You can e-mail her at [email protected]

Lynn is managing director of Bergeson & Campbell, P.C., a Washington, D.C.-based law firm that concentrates on conventional, biobased, and nanoscale chemical industry issues. She served as chair of the American Bar Association Section of Environment, Energy, and Resources (2005-2006). The views expressed herein are solely those of the author. This column is not intended to provide, nor should be construed as, legal advice.

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