WA ST Dept of Ecology 2/15/2022 - Laserfiche WebLink

4. The analysis must be sufficiently complete that an engineering report may be developed for the preferred AKART alternative as well as the preferred alternatives to reach 3 mg/L TIN seasonally, without substantial alterations of concept or basic considerations. The final report must contain appropriate requirements as described in the following guidance (or most recent version): a. The Criteria for Sewage Works Design (ECY Publication No. 98-37, 2019)3 b. Reclaimed Water Facilities Manual:The Purple Book (ECY Publication No. 15- 10-024, 2019)4 5. The analysis conducted for the NRE must include the following elements: a. Wastewater Characterization i. Current flowrates and growth trends within the sewer service area. ii. Current influent and effluent quality. b. Treatment Technology Analysis i. Description of current treatment processes, including any modifications made for optimization or due to corrective actions. ii. Description of site limitations, constraints, or other treatment implementation challenges that exist. iii. Identification and screening of potential treatment technologies for meeting two different levels of treatment: 1. AKART for nitrogen removal (annual basis), and 2. 3 mg/L TIN (or equivalent load), as a seasonal average April - October c. Economic Evaluation i. Develop capital, operation and maintenance costs and 20 year net present value using the real discount rate in the most current Appendix C to Office of Management and Budget Circular No. A-945 for each technology alternative evaluated. ii. Provide cost per pound of nitrogen removed. iii. Provide details on basis for current wastewater utility rate structure, including: 1. How utilities allocate and recover costs from customers. 3 https://apps.ecology.wa.gov/publications/summarypages/9837.html 4 https://apps.ecology.wa.gov/publications/SummaryPages/1510024.html 5 https://www.whitehouse.gov/wp-content/uploads/2020/12/2020_Appendix-C.pdf Puget Sound Nutrient General Permit Page 17