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AMC to III for Colorado is considerably lower than this amount <br />given the fact that our annual rainfall is much lower than the <br />national average. <br />According to the design criteria of ponds 15-P1 and 15-P2, a CN <br />of 74 was used to describe the drainage basins. According to the <br />enclosed Table 2.22 from Barfield's book, it shows that the net <br />effect of the antecedent moisture condition change from II to III <br />is to increase the CN of the ground therefore resulting in a <br />greater runoff. At a CN of 74, converting to AMC III is made by <br />multiplying the CN by 1.17, resulting in a CN of 86.6. At a CN of <br />86.6, the runoff from a 0.4 inch rainfall in 20 minutes exceeds <br />that of a 0.46 inch rainfall at CN 74 (the 10 year event), <br />therefore, the event on 6/29 exceeds the 10 year event and <br />therefore the violations should be vacated. <br />Also, modeling of the Pond 15P-1 watershed for the normal 10 year <br />24 hour event using OSM's storm program shows that the peak flow <br />for this event would be 49.4 cfs. According to the pictures <br />provided by the inspector, the flow on the bridge exceeded 50 <br />cfs. <br />Violations C-92-019 and C-92-021 <br />These violations cite that Rule 4.05.9(e) was violated. I contend <br />that it was not for the following reasons: <br />1) The Rule states that permanent impoundments must be designed, <br />constructed and maintained according to the design requirements <br />of US SCS Public Standard 378 "Ponds". This document makes no <br />reference to specific dewatering times. I have been designing <br />ponds with the CMLRD for 12 years and all of my designs have <br />employed a free pipe as a principal spillway with a dewatering <br />time of 72 hours. The designs for this mine, which have been <br />approved by the Division employ a 72 hour dewatering time. fn a <br />one or two day inspection, I do not know how an inspector can <br />issue violations for the ponds principal spillways being clogged. <br />It has not been proved that the water levels in the ponds above <br />the principal spillways have exceeded 72 hours. <br />2) The enclosed rainfall records for this summer indicate 27.2 <br />inches of rain in three months in an area that normally gets 16 <br />inches of rain a year. This amount of rain is extreme and the <br />