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City of Stockton -2- 14 August 1990 required. Board staff responded on 12 December 1989, agreeing with the general approach but requested a Technical Report at the completion of the work to summarize the City's findings and to recommend future work to insure compliance with the permit. The Technical Report submitted 21 June 1990 by the City, outlining their 1989-90 efforts to determine the cause of the Golden Shiner toxicity, is incomplete and does not contain a single reference to the promised ammonia "directed TRE" tests or their results. Instead, the City has submitted a correlation between total ammonia and fish mortality. The correlation is inadequate as a substitute for the "directed ammonia" TRE for the following reasons: 1 . Un-ionized ammonia, not total ammonia, causes toxicity. The concentration of unionized ammonia cannot be calculated from the information which the City presented, and 2. It does not eliminate other potential classes of chemical toxicants likely to be present in the City's effluent and capable of causing the toxicity. The City now recommends that future work "focus on the role of ammonia and non-polar organics as causes of acute effluent toxicity to Ceriodaohnia and Golden Shiners" (page 2-1 of report) . This work should have already been done during the 1989/90 TIE/TRE work. B. Recommendations 1 . The City of Stockton should submit a Technical Report outlining their 1990/91 Golden Shiner TIE/TRE plans by 7 September 1990. The overall goal of the TIE/TRE plan is to eliminate all Golden Shiner bioassay permit violations. The TIE/TRE should not be considered complete until this is accomplished. The objective of the 1990/91 TIE/TRE should be to determine by 1 May 1991, either the name(s) of the chemical (s) causing fish toxicity or develop and demonstrate an implementable treatment option which will eliminate all winter fish permit bioassay violations. At a minimum, the Technical Report should contain the following information: a) The precise method which will be employed to determine the chemical cause of fish toxicity. This may be by EPA/600/3-88/034, EPA/600/3- 88/035 and EPA /600/3-88/036 procedures with adult Golden Shiners or a surrogate species. However, the phase III confirmation procedure must be with Golden Shiners of a similar size to those presently being employed by the City to assess compliance with its permit. Alternatively, if the City elects the treatability option then it must precisely describe the bench-top tests it proposes to evaluate toxicity removal , a time schedule for these tests, and substantiate these tests with references. b) The name and contract schedule (including deliverables) of the -incipal Consultant responsible for carrying out each phase of the evaluation. c) A schedule indicating the timeframe for accomplishing all the major elements of the project. At a minimum this must include: (i) the number and dates when all phase I (toxicity characterization) , phase