Ctr. for Biological Diversity v. Dep't of Conservation

*165 The Center for Biological Diversity (Appellant) sought a writ of mandate directing the California Department of Conservation, Division of Oil, Gas, and Geothermal Resources (the Department) to order the *732 immediate closure of oil and gas wells injecting fluids into certain underground aquifers. Appellant argued the Department had a mandatory duty to do so under the federal Safe Drinking Water Act (SDWA or the Act; 42 U.S.C. § 330f et seq. ), federal regulations promulgated pursuant to the Act, and a memorandum of agreement executed by the Department setting forth its responsibilities under the Act. The trial court denied the petition, and we affirm. *166 BACKGROUND

The Safe Drinking Water Act

"The SDWA establishes a federally mandated, state-administered regulatory scheme for the protection of drinking water." ( U.S. v. King (9th Cir. 2011) 660 F.3d 1071 , 1077 ( King ).) The Act includes provisions to protect current or potential underground drinking water sources. ( 42 U.S.C. §§ 300h to 300h-8.) To this end, the Act directs the establishment of statewide programs to control underground injections (underground injection control programs, or UIC programs). 1 ( 42 U.S.C.…