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2 <br />operational statistics are calculated for all data prior to the reporting period. <br />Colorado Division of Reclamation and Mine Safety (CDRMS) defined Numeric <br />Protective Levels (NPL) and Early Warning Indicators (EWI) are shown for each <br />constituent at each well where these statistical values apply. <br />Comparison of the data values with the Early Warning Indicators (EWI) and the <br />Numeric Protective Levels (NPL) indicates four values flagged above the <br />calculated limits during the sample period. One of the elevated values is for the <br />constituent total alkalinity and three are for dissolved sodium. The values are <br />distributed among three monitoring wells all down gradient from the 0 - 5 year <br />mining panel including one alluvial well 21-5, and the Uinta and A-groove <br />completion of well 21-3 which is the multiple completion point of compliance well <br />for this mining panel. <br />Alluvial Well 21-5 <br />Analysis of the data collected in the 40th Quarter shows one data point for total <br />alkalinity elevated above the EWI indicator at alluvial well 21-5. The sample, <br />collected in September 2010, indicates a value for total alkalinity of 1250 mg/L. <br />The calculated EWI for this constituent at this monitoring point is 1167 mg/L, a <br />difference of 83 mg/L. The baseline mean value for total alkalinity is 860 mg/L <br />computed from 15 baseline samples. The maximum value observed in the <br />baseline period is 975 mg/L. The operational mean value determined from 75 <br />samples is 883 mg/L. The value of total alkalinity at alluvial well 21-5 has not <br />exceeded the EWI level previously in the period of record. The water elevation <br />during the current reporting period is also indicating a high point elevation. <br />Total alkalinity is comprised of bicarbonate as CaCO3 (1170 mg/L), carbonate as <br />CaCO3 (86 mg/L), and hydroxide as CaCO3 (below detection at < 2mg/L) in the <br />sample collected in September 2010. <br />The historical record of total alkalinity samples collected versus the ground water <br />elevation at alluvial well 21-5 is provided in the following hydrograph.