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purchases surface water from a decreed surface water diversion right owned by the City of Victor (Beaver Creek drainage). Therefore, CC&V believes it is highly unlikely and not reasonable that there is or will be a potential for sufficient ground water to be available to support future uses. Numeric indicator parameters and levels for downgradient compliance points. Based on the jointly reviewed monitoring data, CC&V proposes that the following parameters be the "indicator parameters for the following three ground-water monitoring wells: CRMW-3B-63: Ph 6.0-9.0; SOq 1070 mg/I; CNWAp 0.2 mg/I; Zn(D) 2.0 mg/l; Mn(D) 8.1 mg/I. GVMW-SA-250: Ph 6-56.0-8.5; SO4 X50500 mg/I; CNW,,p 0.2 mg/1; Zn(D) 2.0 mg/l; Mn(D) 1.0 mg/I. WCMW-6-234: Ph 6-36.0-8.5; SO, 230500 mg/1; CNW,,p 0.2 mg/1; Zn(D) 2.0 mg/l; Mn(D) 0:20.5 mg/I. The basis for the changes in the values issued for comment by the OMLR is presented below. The use of the normal distribution to describe lognormally distributed data and the basing of an ambient level on a 99 percent confidence interval describing [hat normal distribution is not well- suited for water quality data. The methodology potentially will lead to citing of normal variations in concentrations as "exceedences" attributed to the monitored operations. Lognormal distributions developed for ambient waters in other locations have been best described by a polynomial that equated to [he 95th or 99th percentiles being best described as the average plus 6 or 7 times sigma. For the Cresson Site, the listed numbers are not used as absolute criteria which, when exceeded, require immediate corrective action. These numbers "trigger" more intense monitoring. They serve as triggers to investigate whether there continues to be a trend upwards suggesting that anthropogenic factors are causing the increase (or decrease in the case of Ph) or whether, over the following months, the concentration returns to "normal. " A period of 2 to 4 weeks after the first observation until the next sample tnay not be long enough to expect ambient conditions to change. This is particularly true for Ph, manganese, and sulfate because the ambient concentrations are entirely a function of the variably-mineralized diatreme and surrounding granodiorite, which covers a large area with many local variabilities. The period of time to ascertain whether a rise (or decline in the case of pH) is abnormal may better be 3 to 6 months after the first anomalous measurement. Conversely, in the case of cyanide, which is not generated in sufficient amounts in nature to reach concentrations that are normally detected in waters, there may be a suitable shorter-term trigger indicating anthropogenic causes, subject to the discussion of cyanide species below. Using WCMW-6-234 as an example, CC&V has the benefit of having collected water quality data from a number of wells upgradient of WCMW-6-234 and of having a relatively large data 6