STATE OF WISCONSIN DEPARTMENT OF NATURAL RESOURCES PUBLIC NOTICE OF INTENT TO REISSUE A WISCONSIN POLLUTANT DISCHARGE ELIMINATION SYSTEM (WPDES) PERMIT No.WI-0025739-10-0 Permittee: Wausau Water Works, 407 Grant St, Wausau, WI, 54403 Facility Where Discharge Occurs: Wausau Water Works WW Treatment Facility, 435 Adrian Street, Wausau, WI 54403 Receiving Water And Location: Wisconsin River in Lower Eau Claire River Watershed of Central Wisconsin River Basin located in Marathon County Brief Facility Description and Summary of Proposed Changes: The Wausau Wastewater Treatment Facility (WWTF) receives wastewater from the City of Wausau, the City of Schofield and the Town of Stettin, in addition to industrial wastewater from industries that are regulated under Wausau's pretreatment program. Wausau WWTF accepts and treats domestic holding tank, septic tank and grease trap interceptors, commercial septage and landfill leachate wastes. Landfill leachate was not accepted in 2022 or 2023, but it may be accepted again in the future. Wausau WWTF accepts approximately 10 gpd of petroleum contaminated groundwater from REI Engineering and also accepts groundwater that was previously contaminated with mineral spirits and pentachlorophenol from Wauleco Sentry Insurance which is pumped and treated prior to discharged into the collection system. Wausau WWTF has an annual average design flow of 8.2 MGD. Influent from the aforementioned sources is first treated at the Wausau WWTF via two mechanical bar screens, followed by the PISTA grit removal system. Subsequent wastewater treatment consists of primary clarification then continues into four selector zones designed for biological phosphorus removal enhancement prior to entering the aeration basins then to then secondary clarifiers. Effluent from the secondary clarifiers travels to tertiary treatment where three disc filters filter TSS out of the secondary effluent. The disc filters may also be bypassed if treatment is not necessary for meeting limitations. Disc filters also have the option of chemical phosphorus removal through chemical precipitation, by the addition of Alum and Polymer to create a floc which removes phosphorus from the secondary effluent. The chemical precipitation option is only used when biological phosphorus removal is not functioning properly. Effluent from the disc filters is disinfected seasonally via ultraviolet disinfection prior to discharge into the Wisconsin River. Waste Activated Sludge is thickened using gravity belt thickeners prior to anaerobic digestion. Anaerobic sludge from the digester is dewatered using belt filter presses which is collected in a hopper where either Class B sludge can be recycled via land application on WDNR approved sites or wet cake can be routed to a thermal dryer where Class A EQ sludge is produced and recycled via land application on WDNR approved sites. Distribution is being considered, but not yet active. Proposed permit changes include the following: 1) effluent limit for mercury removed from permit but monitoring and reporting on mitigation efforts remain, 2) replacement of fecal coliform effluent limits with E. coli limits, 3) addition of monitoring for effluent PFOS and PFOA once every two months and an associated determination of need schedule in accordance with s. NR 106.98(2)(b), Wis. Adm. Code., 5) new Class A sludge requirements, and 6)PFAS sludge sampling has been included in the proposed WPDES permit pursuant to ss. NR 214.18(5)(b) and NR 204.06(2)(b)9., Wis. Adm. Code to quantitate risk. Permit Drafter's Name, Address, Phone and Email: Angela Parkhurst, 1300 W Clairemont Ave, Eau Claire, WI, 54701, (715) 839-3836, Angela.Parkhurst@wisconsin.gov Basin Engineer's Name, Address, Phone and Email: Nicholas Lindstrom, 1300 W Clairemont Avenue, Eau Claire, WI 54701, (715) 492-1787, Nicholas.Lindstrom@wisconsin.gov The Department has tentatively decided that the above-specified WPDES permit should be reissued. Limitations and conditions which the Department believes adequately protect the receiving water are included in the proposed permit. Land application of waste shall be done in accordance with permit conditions and applicable codes. All land application sites shall be approved prior to their use. To receive a list of approved sites, or to be notified of potential approvals, contact the above-named basin engineer. Persons wishing to comment on or object to the proposed permit action, or to request a public hearing, may write to the Department of Natural Resources at the above-named permit drafter's address. All comments or suggestions received no later than 30 days after the publication date of this public notice will be considered along with other information on file in making a final decision regarding the permit. Anyone providing comments in response to this public notice will receive a notification of the Department's final decision when the permit is issued. Where designated as a reviewable surface water discharge permit, the U.S. Environmental Protection Agency is allowed up to 90 days to submit comments or objections regarding this permit determination. If no comments are received on the proposed permit from anyone, including U.S. EPA, the permit will be issued as proposed. The Department may schedule a public informational hearing if requested by any person and shall schedule a public informational hearing if a petition requesting a hearing is received from 5 or more persons or if response to this notice indicates significant public interest pursuant to s. 283.49, Wis. Stats. Requests for a public informational hearing shall state the following: the name and address of the person(s) requesting the hearing; the interest in the proposed permit of the person(s) requesting the hearing; the reasons for the request; and the issues proposed to be considered at the hearing. Information on file for this permit action, including the draft permit, fact sheet and permit application, may be inspected and copied at either the above-named permit drafter's office or the above named basin engineer's office, Monday through Friday (except holidays), between 9:00 a.m. and 3:30 p.m. Please call the permit drafter or basin engineer for directions to their office location, if necessary. Information on this permit action may also be obtained by calling the permit drafter at (715) 839-3836 or by writing to the Department. Reasonable costs (15 cents per page for copies and 7 cents per page for scanning) will be charged for information in the file other than the public notice, permit and fact sheet. Permit information is also available on the internet at: http://dnr.wi.gov/topic/wastewater/PublicNotices.html. Pursuant to the Americans with Disabilities Act, reasonable accommodation, including the provision of informational material in an alternative format, will be made to qualified individuals upon request. NAME OF PUBLISHING NEWSPAPER: Wausau Daily Herald ADDRESS OF PUBLISHING NEWSPAPER: 800 Scott St, Wausau, WI 54402 Date Notice Issued: November 20, 2025 WNAXLP November 20 2025 LWIX0408459