SR0084912_LIQUID WASTE PLAN CHECK

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2.2 Test Protocol Section 8 of NSF/ANSI Standard 40 protocol, "Performance Testing and Evaluation", is included in Appendix B. Start up of the plant was accomplished by filling the plant with 2/3 water and 1/3 raw sewage. The plant was then dosed at the design loading rate of 500 gpd as follows: 6 a.m. to 9 a.m. - 35 percent of daily rated capacity (175 gallons) 11 a.m. to 2 p.m. - 25 percent of daily rated capacity (125 gallons) 5 p.m. to 8 p.m. - 40 percent of daily rated capacity (200 gallons) Dosing was accomplished by opening an electrically actuated valve to feed wastewater to the test plant. Five gallon doses were spread uniformly over each dosing period to comprise the total dose volume for the period. After a start up period (up to three weeks at the manufacturer's discretion), the plant is subjected to the following loading sequence: Design loading - 16 weeks Stress loading - 7.5 weeks Design loading - 2.5 weeks During the design loading periods, flow proportioned 24-hour composite influent and effluent samples are collected five days per week. The influent samples are analyzed for five-day biochemical oxygen demand (BODS) and total suspended solids (TSS) concentrations. The effluent samples are analyzed for five-day carbonaceous biochemical oxygen demand (CBOD5), and total suspended solids(TSS)concentrations. On- site determinations of the effluent temperature and pH are made five days per week. Stress testing is designed to evaluate how the plant performs under non-ideal conditions, including varied hydraulic loadings and electrical or system failure. The test sequence includes (1) Wash Day stress, (2) Working Parent stress, (3)Power/Equipment Failure stress, and (4)Vacation stress. Detailed descriptions of the stress sequences are shown in Appendix B. During the stress test sequences, 24-hour composite samples are collected before and after each stress dosing pattern. The analyses and on-site determinations completed on the samples are the same as described for the design load testing. Each stress is followed by seven consecutive days of dosing at design rated capacity before beginning the next stress test. Sample collection is initiated twenty-four hours after completion of Wash Day,Working Parent, and Vacation stresses, and beginning 48 hours after completion of the Power/Equipment Failure stress. In order for the plant to achieve Class I effluent it is required to produce an effluent, which meets the EPA guidelines for secondary effluent discharge': (1) CBOD5: The 30-day average of effluent samples shall not exceed 25 mg/L and each 7-day average of effluent samples shall not exceed 40 mg/L. 15/10/055/0030 This report may not be reproduced in whole or in part Page 8 of 59 Final Report without the expressed written consent of NSF International January 2019