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Design loading - 16 weeks Stress loading - 7.5 weeks Design loading - 2.5 weeks During the design loading periods, flow proportioned 24-hour composite samples are collected of the influent , and effluent five days per week. The influent and effluent samples are analyzed for carbonaceous five-day biochemical oxygen demand, and total suspended solids concentrations. On-site determinations of the effluent temperature and pH are made five days per week. Upon the request of Orenco System Inc., effluent turbidity was also measured 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 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. (2) Suspended Solids: Each 30-day average of effluent samples shall not exceed 30 mg/L and each 7-day average of effluent samples shall not exceed 45 mg/L. (3) pH: Individual effluent values remain between 6.0 and 9.0. Requirements are also specified for effluent color, odor, oily film and foam, as well as maximum noise levels allowed from the plant. 2.3 Test Chronology The system was installed under the direction of the manufacturer on May 9, 2001. The infiltration/exfiltration t test was completed on May 11, 2001. The plant was filled with 2/3 fresh water and 1/3 raw sewage and dosing was initiated at the rate of 500 gpd, beginning May 13, 2001. Sampling was initiated on May 14, 2001. However, the test was officially started on May 20, 2001 since there were only three sample days during the first week. The stress test sequence was started on September 10 and ended on October 23, and testing was completed on November 16, 2001, 01111/20151060 This report may not be reproduced in whole or in part Page 8 of 46 Final Report without the expressed written consent of NSF International. April 2002 t