STATE OF MARYLAND DEPARTMENT OF THE ENVIRONMENT LAND AND MATERIALS ADMINISTRATION   TENTATIVE DETERMINATION TO RE-ISSUE PERMIT General Discharge Permit for Animal Feeding Operations   The Maryland Department of the Environment (MDE) has made a tentative determination to renew, with modifications, the General Discharge Permit for Animal Feeding Operations, NPDES # MDG01, State Discharge Permit 25AF (25AF Permit).   The 25AF Permit is necessary to protect water quality and to comply with federal requirements under 40 Code of Federal Regulations (CFR) Parts 122, 123, 124, 125, and 412, as well as State requirements under Code of Maryland Regulations (COMAR) 26.08.04.09N. All concentrated animal feeding operations (CAFOs) in Maryland are required to have a discharge permit issued by MDE. Medium and large animal feeding operations (AFOs) are CAFOs if they discharge or propose to discharge to surface or ground water, or both, as defined in COMAR 26.08.03.09A. Any large AFO that does not otherwise qualify as a CAFO is a Maryland Animal Feeding Operation (MAFO) and must have a discharge permit issued by MDE. Other AFOs may be required to be covered under the 25AF permit at the discretion of MDE and the United States Environmental Protection Agency (EPA).   Existing CAFOs/MAFOs: All existing CAFOs and MAFOs that are currently registered under the 19AF General Discharge Permit (19AF Permit) requested continuing coverage under the 19AF Permit after its expiration. These requests were submitted on a Notice of Intent for Continued Coverage (NOICC) form. Once the NOICC was submitted to MDE, the expired 19AF Permit continued in full force and effect until the issuance of the 25AF Permit. To become registered under the 25AF permit, all existing CAFOs and MAFOs must pay any applicable fees, including any past due fees, and submit a current Required Plan within 30 calendar days upon request by MDE.   New Source CAFOs/MAFOs: Any person that wishes to operate a new source CAFO or MAFO in Maryland must be registered under the 25AF Permit before beginning the construction on any part of a new CAFO or MAFO. To become registered under the 25AF Permit, a person must submit to MDE an NOI, Required Plan, and the applicable permit application fee. Pursuant to § 9-323(c) of the Environment Article, Annotated Code of Maryland, the Department may not issue a CAFO discharge permit to a person who begins construction on a new CAFO before obtaining permit coverage from MDE.   The proposed modifications to the 19AF Permit are listed below. The draft 25AF Permit is at least as stringent as the 19AF Permit. Most changes were editorial or clarified the 19AF Permit and were made to provide consistency and reflect current standards. Specific changes include:   Part I      a. Table 2: Clarified that Cattle includes, heifers, steers, bulls, and cow/calf pairs and           excludes mature dairy cows or veal calves      b. Table 2: Clarified that Mature Dairy Cows can be milked or dry.   Part II      a. Clarified in the AFO definition that if the animal is confined for any portion of the day,           it is considered to be on the facility for a full day; the 45 days do not have to be           consecutive; nor the same animals confined in any 12-month period      b. Clarified process wastewater definition      c. Added a definition for “Site”   Part III      a. Added an email address for NOI submittals.      b. Removed separate timeframe for implementation plan submittal and added it to the           submittal as a part of the required plan.   Part IV      a. Clarified that CAFOs need appropriate Air Quality permits before they can operate           incinerators for mortality management.      b. Added reference for pothole management.      c. Added requirements for land application scenarios while winter restrictions are in           place.      d. Clarified that waterline inspections must also occur in between flocks.      e.  Expanded New Source Performance Design Criteria to all animal types.      f.  Added that permittees must notify the department of mailing address changes.   Part V      a. Added an email address for noncompliance notifications.   Part VII      a. Updated continued coverage and permit renewal language.      b. Updated and clarified transfer process.   NOTE: Three in person public hearings and one virtual public hearing on the tentative determination are scheduled:   Location                                         Address                                              Time Thurmont Regional Library,        76 East Moser Road, Thurmont,     October 15, 2025 (6-8pm) Community Room                          Maryland 21788 (301) 600-7205    University of Maryland                 Princess Anne, Maryland 21853    October 21, 2025 (6-8pm) Eastern Shore                                (410) 651-7747 (UMES)    Talbot Community Center           10028 Ocean Gateway, Easton,     October 29, 2025 (6-8pm) Curling Rink                                    Maryland 21601 (410) 770-8050    Virtual On-line                                                                                           October 30, 2025 (6-8pm) Meeting    MDE’s public comment period is October 3, 2025 to November 2, 2025. Written comments concerning the tentative determination will be considered in the preparation of a final determination if submitted by first-class mail or electronic mail to MDE, to the attention of Alexis Capes, Animal Feeding Operations Division Chief, at Maryland Department of the Environment, Land and Materials Administration, 1800 Washington Boulevard, Suite 610, Baltimore, Maryland 21230-1719, or by email at alexis.capes1@maryland.gov. The submittal must include the name, address and telephone number of the person making the comment(s) and, if applicable, the party whom the person making the comment(s) may represent. Please include the 25AF permit number (25AF; MDG01) on the comment document. Comments must be submitted to MDE no later than November 2, 2025.   The fact sheet for the tentative determination and a copy of the 25AF permit may be viewed on the MDE website, www.mde.maryland.gov. Persons may also review the 25AF permit and supporting documentation by contacting Alexis Capes at 443-827-0476 or alexis.capes1@maryland.gov to make an appointment or by written request to Ms. Capes at the above address. If translation services are required, please contact Ms. Capes. 9/24,10/1/25