On April 12, 2019, the U.S. Court of Appeals for the Fifth Circuit issued a decision in Southwestern Electric Company v. U.S. Environmental Protection Agency, Case No. 15-60821. The case involved legal challenges by a number of parties, including environmental groups, to the U.S. Environmental Protection Agency’s (EPA’s) 2015 revision of Clean Water Act wastewater treatment technology standards for coal-burning power plants (known as Effluent Limitations Guidelines or ELGs).
EPA is required to set nationwide ELGs for each major industry that discharges pollutants to U.S. waters but, notwithstanding that the power industry is by far the largest industrial discharger of toxic pollutants to U.S. waters, EPA had not updated the ELGs for power plants since 1982. The 1982 standards, which remained in effect for over 30 years, did not set discharge limits on toxic pollutants such as arsenic, mercury, and selenium based on the “Best Available Technology Economically Achievable” (BAT) and, inter alia, allowed coal-burning power plants to rely on unlined ponds (also known as impoundments) as their primary method for managing wastewater.
2015 rule required more stringent discharge limits for some wastestreams but not others
When EPA updated the power plant ELGs in 2015, it established new, more stringent discharge limits based on BAT for coal-burning power plants’ three largest wastestreams: (1) fly ash transport water, which is used to flush out ash particles that are captured in the smokestack after the coal is burned; (2) bottom ash transport water, which is used to flush out ash from the bottom of the boiler; and (3) wastewater from flue gas desulfurization (FGD or scrubber) systems that many plants use to remove pollutants from their air emissions. The 2015 rule required compliance with these new, more stringent discharge limits “as soon as possible” on or after November 1, 2018 (later extended to November 1, 2020, for bottom ash and FGD) and ultimately no later than December 31, 2023.
For two smaller power plant wastestreams, however, the 2015 rule did not establish more stringent discharge limits. Instead, the rule allowed power plants to avoid any new treatment requirements for both “legacy wastewater”—defined as wastewater that had already been generated as of the compliance date and sent to an impoundment for storage and eventual discharge—and leachate percolating out of on-site impoundments or landfills.
EPA and industry defended the rule
Environmental groups challenged both the legacy wastewater and leachate provisions of the 2015 rule in their petition before the Fifth Circuit. They argued that EPA’s failure to require more stringent treatment technology for legacy wastewater and landfill leachate was unsupported by the record and contrary to the Clean Water Act’s mandate that pollutants not be discharged by industrial sources without treatment to eliminate pollution to the maximum extent achievable using BAT.
Both EPA and an industry intervenor, the Utility Water Act Group, defended the exemption of legacy wastewater and leachate from more stringent requirements. Respondents argued that the approach was justified because EPA lacked information showing that more advanced wastewater treatment technologies were available to treat legacy wastewater. With respect to leachate, respondents argued that it was a small wastestream relative to the other, larger wastestreams for which the ELG rule set more stringent discharge limits, and that the more stringent limits on larger wastestreams constituted “reasonable progress” toward eliminating pollutant discharges from power plants. EPA argued that it had reasonably determined that it did not need to impose more stringent discharge limits on leachate.
Court held that standards must be based on state-of-the-art technologies
The Fifth Circuit held that EPA’s failure to require the most effective treatment technologies for both legacy wastewater and leachate was unlawful, strongly emphasizing EPA’s responsibility to require that industry use modern, state-of-the-art technologies to eliminate its pollution. The court further noted that EPA’s failure to collect sufficient data concerning the availability of treatment technologies to address legacy wastewater was a problem of its own making. With respect to leachate, the court agreed with petitioners that EPA’s justifications for not setting more stringent discharge limits were not adequately supported. Noting that EPA’s failure to require the most effective technologies was, in effect, a decision to continue allowing them to meet only the 1982 ELG standards, the court observed that, “[i]t was as if Apple unveiled the new iMac, and it was a Commodore 64.” The Fifth Circuit struck down the provisions of the ELG rule that did not require the industry to meet new treatment standards and remanded them back to EPA.
Now EPA must conduct a new rulemaking to set BAT-based discharge limits for these two wastestreams. EPA has not yet sought public input as part of this new rulemaking, but recently issued a separate proposed rule revising other provisions of the power plant ELGs in which it is proposing to continue to allow power plants to use surface impoundments under certain circumstances. EPA’s latest proposed rule suggests that it might seek only improve its rationale and not the substance of its standards on power plant legacy wastewater and leachate in response to the Fifth Circuit’s decision.