On Sept. 2, 2010, EPA released two draft rules for implementing the agency's new permitting requirements under the Clean Air Act's Prevention of Significant Deterioration (PSD) program. In the first, EPA issued a proposed State Implementation Plan (SIP) call, to find that the SIPs of 13 states, including Texas, are "substantially inadequate" because their PSD programs do not apply to new or modified greenhouse gas-emitting sources. EPA seeks to require the non-compliant states to issue revised SIPs within 12 months that address permitting requirements for greenhouse gas emissions under the PSD program consistent with the Tailoring Rule. EPA proposes publishing the final SIP call in early December 2010, which means that revised SIPs would be due in December 2011, unless a state has asked for an earlier deadline. In its second rule, EPA proposes assuming responsibility for PSD permitting via a Federal Implementation Plan (FIP) for greenhouse gas emissions in states that do not timely submit compliant SIPs. Before assuming responsibility for PSD permitting via a FIP, EPA must determine that the relevant SIP is "substantially inadequate." It must also provide the state with a "reasonable" amount of time to cure its defective SIP; here EPA is proposing 12 months to submit corrective SIPs. Under EPA's proposal, new or modified large greenhouse gas sources may not be able to obtain PSD permits (and thus be denied to construct or modify some units if they have annual emissions exceeding 75,000 tons of carbon dioxide) because neither an approved SIP nor FIP will be in place until late in 2011.