# Approval and Promulgation of Implementation Plans and Designation of Areas for Air Quality Planning Purposes; Arizona
**AGENCY:**
Environmental Protection Agency (EPA).
**ACTION:**
Proposed rule.
**SUMMARY:**
EPA is proposing to approve the maintenance plan for the Ajo area in Arizona and grant the request submitted by the State to redesignate this area from nonattainment to attainment for the National Ambient Air Quality Standards for sulfur dioxide (SO <sub>2</sub> ).
**DATES:**
Comments on this proposal must be received by December 3, 2003.
**ADDRESSES:**
Comments should be mailed or emailed to Wienke Tax, Office of Air Planning (AIR-2), U.S. Environmental Protection Agency, Region 9, 75 Hawthorne Street, San Francisco, CA 94105-3901, *[email protected].* Comments may also be submitted through *http://www.regulations.gov.* We prefer electronic comments. You can inspect copies of EPA's *Federal Register* document and Technical Support Document (TSD) at our Region IX office during normal business hours (see address above). Due to increased security, we suggest that you call at least 24 hours prior to visiting the Regional Office so that we can make arrangements to have someone meet you. The *Federal Register* notice and TSD are also available as electronic files on EPA's Region 9 Web Page at *http://www.epa.gov/region09/air.*
Copies of the State Implementation Plan (SIP) materials are also available for inspection at the address listed below: Arizona Department of Environmental Quality, 1110 W. Washington Street, First Floor, Phoenix, AZ 85007, Telephone (602) 771-4335.
**FOR FURTHER INFORMATION CONTACT:**
Wienke Tax, Air Planning Office (AIR-2), Air Division, U.S. EPA, Region 9, P.O. Box 86825, Tucson, AZ 85754-6825. Telephone: (520) 622-1622. E-mail: *[email protected]* , or check *http://www.epa.gov/region09/air*
**SUPPLEMENTARY INFORMATION:**
In the Rules and Regulations section of this *Federal Register* , we are approving the maintenance plan for the Ajo SO <sub>2</sub> nonattainment area. We are also approving the State of Arizona's request to redesignate the Ajo area from nonattainment to attainment for the primary SO <sub>2</sub> NAAQS. We are taking these actions without prior proposal because we believe that the revision and request are not controversial. If we receive adverse comments, however, we will publish a timely withdrawal of the direct final rule and address the comments in subsequent action based on this proposed rule. We do not plan to open a second comment period, so anyone interested in commenting should do so at this time. If we do not receive adverse comments, no further activity is planned. For further information, please see the direct final action.
Dated: September 25, 2003.
Deborah Jordan,
Acting Regional Administrator, Region IX.