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any 5-day period would be combined into "composite" samples for analysis. Three such 5-day periods would be monitored by the permittee each month. The concentra- tions measured in the 3 composite samples would be averaged to determine compliance with the 30-day average limitation. In addition, one grab sample would be taken during each 5-day period and analyzed to determine compliance with the daily maximum limitation. In addition to changing the sampling frequency and adopting a composite approach to reduce the number of lab procecures re- quired, the language of the permit under section A.4. should be changed to make clear that data submitted by the permit:tee will be used to determine compliance, and not merely as an "indication of probable compliance or noncompliance...." II. blonitoring Points other than Outfall 001. Since the Q7-10 for Ralston Creek is zero, the entire discharge from the Cotter mining operation must not cause the stream standard to be exceeded. Therefore it is not enough to monitor only the discharge from the sedimentation ponds. Since the Division has adopted an effluent limitation which allows the equiva]_ent of the entire stream standard to be discharged from the: sedimen- tation ponds, then there must be no discharge of the regulated pollutants from any other point of the mining operation. For this reason, EDF believes that the Division is fully justi- fied in requiring control plans to prevent surface watEar runoff from the ore piles and ore sorter areas from reaching the si:ream, and to require isolation of the waste rock disposal area from the stream. But in order to ensure that no additional pollutants are dis- charged from any of these points or from seepage throu~.~h unlined ponds or inadequately maintained berms, EUF requests that ground- water and in-stream monitoring be added to the permit. Groundwater monitoring can be much less frequent than effluent dis~~harge moni- toring, and we would leave the frequency to the discre~=ion of the Division. In-stream monitoring should be tailored to :Ldentify pollutants carried into the stream by surface water ru~iof_f, and should therefore be triggered by precipitation events. The number of events to be sampled could be limited by sea:~on and other factors, but the sampling program would have to lie care- fully defined to measure contributions of pollutants from the mining operation which were not discharged from the sedimentation ponds. III. Analytical Methods Samples should be analyzed using standard procedures approved - 5-