ELR Citation: 53 ELR 20074
No(s). 20-1335 (D.C. Cir. May 9, 2023)

The D.C. Circuit vacated EPA's withdrawal of its determination to regulate perchlorate in drinking water. An environmental group argued EPA lacked the authority to withdraw the determination under the SDWA, and that even if it did have such authority, it acted arbitrarily and capriciously in doing so. The court found that because the SDWA requires that EPA "shall" regulate after making a regulatory determination, it lacks authority to withdraw that determination and decide that it "shall not" regulate. Because the court concluded that the Agency lacked authority to withdraw its regulatory determination, it did not reach the group's arbitrary and capricious challenge. It vacated the withdrawal and remanded to EPA for further proceedings.