The U.S. Environmental Protection Agency (EPA) promptly rejected a petition by the Center for Biological Diversity (CBD) requesting that the agency undertake a novel expansion of its authority under the Toxic Substances Control Act (TSCA) to regulate carbon dioxide to address ocean acidification (OA). Specifically, the CBD petition, filed on June 30, 2015, requested EPA to find that carbon dioxide posed an unreasonable risk, particularly due to OA concerns, and initiate a rulemaking to regulate emissions under TSCA Section 6, or, alternatively, to issue a TSCA Section 4 rule to require testing to determine toxicity, persistence, and other characteristics of carbon dioxide emissions that affect human health and the environment.

In announcing the decision to dismiss the petition on September 29th (formally published in theFederal Register on October 7th, 80 Fed. Reg. 60,577), EPA declared that the “petitioners provided neither adequate specifics on the relief sought under TSCA, nor sufficient information on the costs and benefits associated with a requested regulatory option to allow EPA to make the unreasonable risk finding” to support regulation under Section 6. In short, the petition identified a “global environmental concern” but suffered from “a nearly complete lack of detail as to the TSCA risk management sought” beyond a variety of broad and generic suggested actions (such as “mandatory emissions reductions.” More specificity in identifying potential TSCA regulatory actions, and identifying specific costs and benefits, is necessary.

Likewise, EPA found that CBD did not present “information sufficient to establish that testing under TSCA section 4 is necessary to develop data that would allow EPA to determine whether anthropogenic CO2 emissions present an unreasonable risk of injury under TSCA.” Here, too, the petition did not support the need to mandate testing under TSCA, particularly given that the adverse effects of CO2 emissions on OA are not in dispute, and the fact that a range of federal studies already are underway to collect information on OA and its impacts.

EPA recognized, as it did in its 2009 greenhouse gas “endangerment finding,” that CO2 emissions contribute to OA, and that OA has adverse impacts on marine ecosystems. However, the agency made clear that “actions to address CO2 emissions under authorities other than TSCA [namely under the Clean Air Act and Clean Water Act] could reduce the risk posed by CO2 more efficiently and effectively at this time.” The notice announcing the petition denial includes a lengthy catalogue of actions taken by EPA and other parts of the federal government “on many fronts to address climate change and related concerns, including ocean acidification.”

EPA’s action to deny the petition seemingly closes the door to the use of TSCA to address carbon dioxide emissions and climate change, which the agency and petitioners alike will seek to confront through more traditional regulatory means.