Document Headings

                    Document headings vary by document type but may contain                    the following:                  
                -                       the agency or agencies that issued and signed a document                    
                -                       the number of the CFR title and the number of each part                      the document amends, proposes to amend, or is directly                      related to                    
                -                       the agency docket number / agency internal file number                    
                -                       the RIN which identifies each regulatory action listed in                      the Unified Agenda of Federal Regulatory and Deregulatory                      Actions                    

                    See the                                          Document Drafting Handbook                                        for more details.                  

###### Environmental Protection Agency

          - 40 CFR Parts 52 and 81
          - [EPA-R07-OAR-2021-0391; FRL-8693-03-R7]

# AGENCY:

Environmental Protection Agency (EPA).

# ACTION:

Proposed rule; reopening of comment period.

# SUMMARY:

                        On June 29, 2021, the Environmental Protection Agency (EPA) proposed a rule titled, “Air Plan Approval; Missouri Redesignation Request and Associated Maintenance Plan for the Jefferson County 2010 SO2                         1-Hour NAAQS Nonattainment Area.” In response to stakeholder requests, the EPA is reopening the comment period for this proposed rule.                    

# DATES:

The comment period for the proposed rule published on June 29, 2021 (86 FR 34177), is reopened. Written comments must be received on or before September 16, 2021.

# ADDRESSES:

                        You may send comments, identified by Docket ID No. EPA-R07-OAR-2021-0391 to                         *https://www.regulations.gov.*                         Follow the online instructions for submitting comments.                    

*Instructions:*                         All submissions received must include the Docket ID No. for this rulemaking. Comments received will be posted without change to                         *https://www.regulations.gov,*                         including any personal information provided. For detailed instructions on sending comments and additional information on the rulemaking process, see the “Written Comments” heading of the                         **SUPPLEMENTARY INFORMATION**                         section of this document.                    

# FOR FURTHER INFORMATION CONTACT:

                        Ashley Keas, Environmental Protection Agency, Region 7 Office, Air Quality Planning Branch, 11201 Renner Boulevard, Lenexa, Kansas 66219 at (913) 551-7629, or by email at:                         *keas.ashley@epa.gov.*

# SUPPLEMENTARY INFORMATION:

                    On June 29, 2021, the EPA published in the                     **Federal Register**                     (86 FR 34177), a notice of proposed rulemaking, proposing to approve the State of Missouri's December 27, 2017, request for the EPA to redesignate the Jefferson County, Missouri, 2010 1-hour sulfur dioxide (SO2) National Ambient Air Quality Standard (NAAQS) nonattainment area to attainment and to approve a State Implementation Plan (SIP) revision containing a maintenance plan for the area. The State provided supplemental information on: May 15, 2018; February 7, 2019; February 25, 2019; and April 9, 2021. In response to these submittals, on June 28, 2021, the EPA proposed to take the following actions: Approve the State's plan for maintaining attainment of the 2010 1-hour SO2                     primary standard in the area; and approve the State's request to redesignate the Jefferson County SO2                     nonattainment area to attainment for the 2010 1-hour SO2                     primary standard.                

                    For more detailed information about this matter, please refer to the June 29, 2021                     **Federal Register**                     document.                

                    The notice of proposed rulemaking, as initially published in the                     **Federal Register***,*                     provided for written comments to be submitted to the EPA on or before July 29, 2021 (a 30-day public comment period). Since publication, the EPA was made aware that the Technical Support Document (TSD) associated with the proposed rule was not included in the docket. The TSD was uploaded to the docket on July 18, 2021. Subsequently, the EPA received stakeholder requests                           ( print page 45951)                        for the comment period to be extended. Accordingly, the EPA is reopening the public comment period to afford stakeholders the ability to fully evaluate the EPA's proposed action and an opportunity to comment on the technical basis for the EPA's proposed action. The EPA will address all comments received on the original proposal and on this supplemental notice in our final action.                

Dated: August 11, 2021.

Edward H. Chu,

Acting Regional Administrator, Region 7.

[FR Doc. 2021-17587 Filed 8-16-21; 8:45 am]

BILLING CODE 6560-50-P