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HomeMy WebLinkAbout20241113 Oshkosh Start Up Inspection Approval Phosphates November 13, 2024 PWS ID 47104574 Oshkosh Waterworks -MC Diane Bartlett, City Clerk Winnebago County City of Oshkosh 215 Church Ave PO Box 1130 Oshkosh, WI 54901-1130 Subject: Start-Up Inspection / Authorization for Phosphoric Acid and Sodium Hydroxide Chemical Feed Systems Dear Ms. Bartlett: On July 8, 2024, I conducted a start-up inspection of the Oshkosh Waterworks corrosion control treatment chemicals. At that time, most of the chemical feed system had been installed, but not all the feed pumps that were onsite matched the original approval letter. This letter summarizes the final installed equipment at Oshkosh Waterworks following a delay to accommodate the delivery of the originally approved phosphate pumps and a subsequent After-the-Fact review (W-2024-0935) for two of the sodium hydroxide feed pumps. Approval to begin feeding phosphoric acid was given via e-mail on April 10, 2024, when Oshkosh Waterworks installed temporary pumps per W-2023-0590A. Those pumps have been removed from service and new chemical feed pumps installed as noted below. Conditional approval to begin feeding the sodium hydroxide was given via e-mail on August 14, 2024. Based on my inspection and subsequent correspondence, the completed work, described below, meets the department’ approval(s) W-2023-0590 dated August 11, 2023. In general, the following work was completed as part of this project: 1. Installation of new phosphoric acid chemical feed system including chemical pumps (see change 1 below), solution day tank with scale, a bulk storage tank with radar level sensor, and CPVC piping. 2. Installation of new sodium hydroxide chemical feed pumps (see change 2 below) and CPVC piping. The following changes to the design are not reflected in the plan sheets or the Department’s plan approval; however, these changes are acceptable: 1. The phosphoric acid feed pumps (Milton Roy Model No. MRB - GLOBAL MROY A) were approved with a maximum feed rate of 2.32 gph but upon arrival were determined to have a maximum feed rate of 2.20 gph. 2. The sodium hydroxide feed pumps were approved as two larger pumps (Milton Roy Model No. MRB - GLOBAL MROY B, maximum 2,040 gallons per day) and two smaller pumps (Milton Roy Model No. MRB - GLOBAL MROY A, maximum 55.68 gallons per day). The larger pumps were installed per the original plan review document, but the smaller pumps were replaced with Milton Roy Model No. MRB - GLOBAL MROY A, maximum 148.8 gallons per day per the ATF plan review letter W-2024-0935 issued on October 31, 2024. State of Wisconsin DEPARTMENT OF NATURAL RESOURCES Agricultural Services Center 3369 West Brewster Street Appleton WI 54914-1602 Please note that Oshkosh is required to take two rounds of standard lead/copper monitoring before April 21, 2025, per the Department Action on Corrosion Control Treatment Study letter dated April 21, 2022. The first round was completed in fall 2024, the second round must be completed between Jan 1, 2025 and April 21, 2025. If you have any questions regarding this approval, or wish to discuss this in further detail, please feel free contact me by phone at (920) 362-6629 or by email Jamie.douglas@wisconsin.gov. Sincerely, Jamie Douglas, P.E. Water Supply Engineer Ecopy: NER FILE JaNelle Merry, DNR Green Bay Ken Scherer, DNR Madison Jason Ellis, Oshkosh Brad Rokus, Oshkosh Bob Dreikosen, Oshkosh Susan Wojtkiewicz, Donohue & Associates