PUBLIC COMMENT PERIOD U.S. OIL & REFINING CO. NATIONAL POLLUTANT DISCHARGE ELIMINATION SYSTEM DRAFT PERMIT RENEWAL 12:01 am, October 29, 2025 through 11:59 pm, December 10, 2025 The Dept of Ecology (Ecology) invites you to comment on the proposed National Pollutant Discharge Elimination System (NPDES) Permit Renewal and Fact Sheet for U.S. Oil & Refining Co. (USOR), Tacoma (Pierce County). The comment period begins at 12:01 am on October 29, 2025 and ends at 11:59 pm on December 10, 2025. USOR operates a petroleum refinery at 3001 Marshall Avenue, in Tacoma (Pierce County), Washington. USOR operates an industrial wastewater treatment plant and a stormwater treatment system that discharge treated wastewater and stormwater to the Blair Waterway (Commencement Bay). Read the proposed permit online at https://ecology.wa.gov/us-oil-refining; in-person at the Department of Ecology, 300 Desmond Drive SE, Lacey, WA, 564-669-4474; or in-person at the Tacoma Public Library, 1102 Tacoma Ave S., Tacoma. Written comments may be submitted online at https://swm.ecology.commentinput.com?id=QN4JK3x2fi or by mail to Greg Gould, Department of Ecology, Industrial Section, P.O. Box 47600, Olympia, WA 98504-7600. If you have questions about the permit, call 360-819-6426. For a number of pollutants, including biochemical oxygen demand, chemical oxygen demand, total suspended solids, oil and grease, phenolic compounds, ammonia as nitrogen, sulfide, hexavalent chromium (concentration-based), and pH the proposed permit for the USOR's treated wastewater discharges will keep the same legal limits as the old permit. However, the new draft permit includes the following new restrictions and requirements: Maximum allowable discharge amounts for hexavalent and total chromium. Limits for stormwater discharges. Stormwater benchmarks and corrective actions. Acute Whole Effluent Toxicity testing in the last summer and last winter of the new permit cycle. Chronic Whole Effluent Toxicity compliance testing eight times throughout the new permit cycle. Updated operations and maintenance manual for wastewater and stormwater systems. Updated the Pollution Prevention Plan. A dioxin study. A per-and polyfluoroalkyl substances (PFAS) study on wastewater effluent. A nutrient study to evaluate nutrient loading to the wastewater treatment plant. A tentative virtual public meeting, followed by a hearing to accept oral comments, will take place December 3, 2025, starting at 6:00 p.m. Register online for the public hearing at: https://waecy-wa-gov.zoom.us/meeting/register/z45H Zl6UQfqK4DwRYbCVQA. Registration is required. After registering, you will receive a confirmation email containing information about joining the hearing. The public hearing will be held if Ecology receives significant public interest. Ecology will notify interested parties prior to cancelling the tentative public hearing if we have not received significant interest by December 1, 2025. When the comment period ends, we will review all comments received and make a final decision on the permit. To request an ADA accommodation, email tara.roberts@ecy.wa.gov, call 360-280-4325, or dial 711 to call through the Washington Telecommunications Relay for services like text telephone (TTY). Visit Ecology.wa.gov/ADA for more accessibility information. IPL0284358 Oct 29 2025