Largely in response to Barnett shale concerns in North Texas, the Texas Commission on Environmental Quality has developed a new more stringent permit and permit by rule (PBR) for oil and gas facilities. For example, the proposed PBR will include operating specifications and emissions limitations for typical equipment during normal operations, including production and planned maintenance and start up and shut down. It also specifically addresses the appropriateness of multiple authorizations at one contiguous property and includes revised criteria for registration and changes at existing authorized sites. Existing oil and gas facilities currently authorized under a PBR and that remain unmodified are not affected by this proposal except if they notify TCEQ by 2013 that they are operating under a historical PBR or standard permit. They must also meet planned maintenance start up and shutdown requirements by Jan. 5, 2012.