State Water Board Adopts Toxicity Provisions
On December 1, the State Water Resources Control Board (State Water Board/SWB) adopted the toxicity provisions for inland surface waters (Provisions). These provisions have been developed over the course of several years with several rounds of input from CASA and other stakeholders in the clean water community. Over the month of November, CASA met with SWB members, staff, and counsel to discuss the remaining issues and details for the practicable implementation of the regulations. Notwithstanding CASA’s overarching concerns with the Provisions’ use of numeric limits for chronic toxicity and mandating the Test of Significant Toxicity (TST), from CASA’s perspective, the final version of the Provisions and adopting Resolution represent an acceptable compromise.

Perhaps most importantly, the State Water Board has committed to proceeding with a study of the ceriodaphnia dubia reproduction test (a key point of concern for CASA) and conducting a meaningful check in with the SWB Members when the study is complete. The final versions of the Provisions and supporting materials will soon be available on the SWB’s Toxicity program page, and the first stakeholder meeting for the cerio study has been scheduled for December 8. Thank you to all of our members who helped us work on the Provisions over these last few years. Please reach out to Jared Voskuhl if you have questions.