2014-10-10_PERMIT FILE - C1996083 (4)

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Exhibit A Bowie Resources, LLC The amount of the exchange water to be released from the Holy Terror Reservoir and/or the Rex Reservoir will be calculated as the difference between the average daily flow as recorded at the downstream monitoring station and the amount of flow that was predicted to have occurred at this station based upon the application of the baseline regression equation(s) to the streamflow at the upstream monitoring station. The amount of water at the upstream monitoring station to be used in the regression equation will be based upon the station's average daily "native flow ". Native flow is defined as the average daily flow measured at the upstream monitoring station, minus the amount of water released from the exchange storage pools, plus transit loss. An example of the proposed exchange procedure is outlined below. Step 1. Calculate the regression equation. Regression equations describing the streamflow relationship between the upstream monitoring station (independent variable) and the downstream monitoring station (dependent variable) will be calculated based upon the 2014 and 2015 baseline monitoring program (pre- mining). For purposes of this illustration, a single regression equation was developed based upon the measured streamflow values collected at the two gage sites over the period June 26, 2014 through July 26, 2014. During this time streamflows were low, generally less than 3.5 cfs except for brief periods following thunderstorm activity within the basin. Exhibit A -1 provides a time series display showing the recorded streamflow volumes at the upstream and downstream monitoring stations over the 30 day period used in this illustration The collected data indicates there exists a strong relationship between the two monitoring stations and that during low flow conditions following the active snowmelt season, West Fork Terror Creek between the two gage sites loses a small amount of water. The regression equation has a calculated Rz of 0.955. RZ is a statistical measure of how well the regression line approximates the real data points; a R2 value of 1.0 indicates that the regression line perfectly fits the data. The calculated regression equation for this period is representative of what is expected following the two year baseline study period (2014 and 2015); however, the equation will change as more data becomes available for review and analysis. The currently calculated regression equation for the lower base flow conditions is shown below: y = 1.0031x - 0.0989 in which y is the predicted average daily streamflow at the downstream gage site x is the measured average daily streamflow at the upstream gage site