Clean Air Council, 60-Day Notice of Intent to Sue (May 30, 2013). The Clean Air Council (CAC) submitted to EPA a 60-day Notice of Intent to Sue, citing EPA’s failure to respond to a February 2012 petition in which CAC asked EPA (1) to make a finding that Pennsylvania was not implementing the requirements of its State Implementation Plan, (2) to determine that Pennsylvania was not adequately administering and enforcing its Clean Air Act Title V permitting program, and (3) to apply sanctions for these failures. These failures are in connection with Pennsylvania’s alleged failure “to perform legally adequate and complete single source determinations for the oil and gas industries.”