A history of legacy mining in California has resulted in an estimated 200,000 abandoned mine openings. These mines, if left unremediated, can pose a hazard for humans and the environment. The California Department of Conservation – Abandoned Mine Lands Unit (AMLU) has an interest in protecting the public from the hazards found in and around abandoned mine sites, which often provide habitat for bats and other wildlife. AMLU houses an interdisciplinary team of geologists, environmental scientists, and GIS professionals that possess a unique suite of training and experience to survey subterranean habitat for hazards and wildlife and provide technical expertise. AMLU works with landowning agencies to assess physical risks at historic mines and remediate hazards with bat-compatible closures, when possible, to protect the public and wildlife. AMLU has remediated more than 1,600 abandoned mine features in California since 2000. These mines provide habitat for several California Species of Special Concern, especially Townsend’s big-eared bat (Corynorhinus townsendii) and California leaf-nosed bat (Macrotus californicus). AMLU works closely with Bat Conservation International to complete bat surveys and ensure that remediation recommendations align with habitat conservation goals.