On February 25, 1999, EPA Region VIII published an Immediate Final Rule at 64 FR 09278 authorizing changes to Wyoming's hazardous waste program under the Resource Conservation and Recovery Act (RCRA). At that time, we determined that the changes to Wyoming's hazardous waste program satisfied all requirements for final authorization and authorized the changes through an Immediate Final Rule. The Immediate Final Rule was to be effective on April 26, 1999 unless significant written comments opposing the authorization were received during the comment period. At the same time, in the event we received written comments, we also published a Proposed Rule at 64 FR 09295 to authorize these same changes to the Wyoming hazardous waste program. As a result of comments received on the Immediate Final Rule and the passage of Wyoming Senate File 147 (SF 147), we withdrew the Immediate Final Rule on April 23, 1999 at 64 FR 19925, reopened the Public Comment Period until July 22, 1999 at 64 FR 19968, and went forward with the Proposed Rule. In addition, we held Public Hearings on June 29 and 30, 1999. By today's action, we are issuing a Final Rule authorizing the changes to the Wyoming hazardous waste program as listed in the Immediate Final Rule at 64 FR 09278 and responding below to all of the comments received.