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Southern California Alliance of Publicly Owned Treatment Works v. EPA


Southern California Alliance of Publicly Owned Treatment Works v. EPA, US District Court for the Eastern District of California

On December 16, NACWA joined several California water organizations to file litigation challenging EPA’s efforts to impose certain testing requirements for whole effluent toxicity (“WET”) on dischargers without going through the rulemaking process required by the Administrative Procedure Act (APA).

EPA has pressured state agencies to adopt the Test of Significant Toxicity (TST), although the applicable regulations do not identify TST as an acceptable methodology, and although NACWA and other stakeholders have raised significant technical questions about the validity of TST.

The litigation will directly challenge the TST, the use of which will result in an increased cost to members to undertake the additional replicate samples necessary to reduce the likelihood of being found in violation; an increased frequency of false failures in toxicity testing; and, thus, a higher alleged incidence of noncompliance with NPDES permits, potentially resulting in civil and even criminal liability. Furthermore, the litigation will underscore that rulemaking without notice and comment violates the APA, stifles public participation, and harms the Plaintiffs’ members as well as the public in general.

NACWA is concerned that once the TST is used in California POTW permits, it will be more broadly applied in other states. NACWA’s participation provides a national perspective on the concerns over use of the TST method, the way unpromulgated guidance is being imposed, and the implications this case could have on clean water utilities nationwide.


Use of the TST to evaluate WET tests was first contemplated at the national level in 2010 when EPA’s Office of Wastewater Management released draft guidance to states and EPA Regions. EPA did not seek official comment on the document and made no attempt to make it publicly available. In fact, NACWA only became aware of the draft guidance when the document was forwarded to the Association by one of the few recipients. Thereafter, NACWA and several other stakeholders provided EPA with detailed comments outlining significant concerns with the TST.

In June 2010, EPA finalized the TST guidance document. Comments were solicited and received from states and regions, but once again EPA did not seek public comments. The final memo transmitting the document makes no mention of the extensive comments that NACWA and other stakeholders submitted and does nothing to address the significant concerns raised.

Even though EPA has issued no further guidance on the TST and has failed to seek formal public comment on the procedure, EPA Region 9 has continued to push for its use in permits, particularly in California. Thus, NACWA has been closely following the developments in California for several years. At the request of Member Agency, the Sanitation Districts of Los Angeles County (LACSD), in January 2015, NACWA provided comments to the Los Angeles Regional Water Quality Control Board on the Tentative Permit for LACSD’s San Jose Creek Water Reclamation Plant, which included use of the TST. NACWA’s comments on the permit underscored the flaws in the TST and the fact that it has never been officially proposed for inclusion as a part of the WET test methods at 40 CFR Part 136. NACWA also raised concern with the permit’s proposed prohibition on conducting five concentration tests (as currently required in 40 CFR Part 136) and dose-response evaluations when using the TST, further compounding the flaws in the TST. Instead, the state was limiting LACSD to two test concentrations.

Recognizing their vulnerability in using the TST and specifically a two concentration TST test in Clean Water Act permits, EPA Region 9 suggested to the California State Water Resources Control Board that it seek approval for use of the TST through the EPA Alternative Test Procedure (ATP) process. EPA Region 9 granted this ATP in March of 2014. This procedural end-run was the target of an earlier complaint filed by the Southern California Alliance of Publicly Owned Treatment Works (SCAP). The ATP in question was ultimately withdrawn for procedural reasons and the case determined moot. At the time, NACWA decided not to engage in the case given its limited focus on the ATP issue.

However, documents uncovered through a Freedom of Information Act (FOIA) request filed by SCAP brought new, relevant facts to light and a Motion for Reconsideration was filed with the court. The order granting the motion for reconsideration raised the more fundamental question of whether the TST is an approved Part 136 method that can be utilized in a National Pollutant Discharge Elimination System (NPDES) permits – a question that is relevant for dischargers nationwide.

In November 2015, NACWA filed an amicus brief in Southern California Alliance of Publicly Owned Treatment Works v. EPA outlining the significant scientific, regulatory, and legal concerns with the use of the TST, with particular attention on EPA’s attempts to impose this test evaluation method without going through the required public notice-and-comment procedures. In August 2016, the court dismissed the suit due to a procedural issue. However, the court’s decision opened the door for new litigation to be filed if permits are justified based on the TST guidance document itself.

Current Litigation

SCAP is now leading a new challenge to the use of the TST, building off the opening provided by the court in the previous case. NACWA members in California operate POTWs pursuant to NPDES permits issued by the State Water Board, Regional Water Quality Control Boards, or USEPA that include chronic toxicity testing and compliance provisions. Many POTWs, including one NACWA Member Agency who reached out to us directly, have recently received or are in the process of negotiating new or revised NPDES permits with these regulatory agencies that include chronic toxicity testing and compliance provisions based on the unpromulgated TST.

If EPA is not enjoined from the use of the unpromulgated TST for testing and compliance purposes in NPDES permits, many, if not all, of these POTWs as well as other dischargers in the state will be required to begin using and reporting results from an unpromulgated statistical procedure that, due to the nature of the procedure, will adversely affect their compliance status.



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