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Semi-conservative nature of replication

Ecology Will Complete the Dissolved Oxygen TMDL Consistent with the Foundational Concepts The foundational concepts in this document are the result of substantial deliberation by the Spokane River Collaboration. This effort placed completion of the Draft TMDL “on hold” prior to its being made final and submitted to the Environmental Protection Agency for review. Ecology will re-draft the Draft Spokane River Dissolved Oxygen TMDL to include a MIP consistent with the principles described here. The re-draft will be subject to the same public review process and administrative procedures used for the earlier Draft TMDL. As well, Ecology will continue to work on a government-to-government basis with the Spokane Tribe of Indians to ensure compliance with downstream Tribal water quality standards. Waste Load Allocation Targets A TMDL requires waste load allocations (WLA) for the affected NPDES permit holders. These targets, expressed in concentrations in the draft TMDL, will be slightly revised in the re-drafted TMDL to reflect upstream permitting in Idaho and an April-October rather than June-October critical period (see the boxed table on page 24, Draft Total Maximum Daily Load to Restore and Maintain Dissolved Oxygen in the Spokane River and Lake Spokane, October 2004). The total phosphorus concentrations, as allocations in the TMDL rounded to the nearest microgram will remain 10µg/l. V21 3 In the MIP, however, the 10 µg/l total phosphorus targets will be expressed as pounds of phosphorus discharge in the River based on the discharge volume estimates established through the Collaboration. The translation from concentration to pounds of phosphorus forms the basis for measuring success in meeting each phosphorus waste load allocation target under the MIP. Success in meeting the pounds of phosphorus target will be achieved by the installation of the most effective feasible phosphorus removal treatment technology and implementation of other phosphorus reduction actions that together result in the net pounds of phosphorus discharged to the River by the dischargers being equal to or less than the target pounds. The following table shows the pounds per day phosphorus targets for each Washington State NPDES permit holder as they will be expressed in the MIP based on projected flows for 2017