Laserfiche WebLink
October 1, 2014C-1992-080/Carbon Junction MineMLT <br />Discussion <br />An exact determination of the peak rates of flow that may have occurred during September is <br />impossible to make. However, asearchof the Community Collaborative Rain, Hail & Snow <br />(CoCoRaHS) Network data for the latter half of September revealedthe following precipitation <br />totals for specific dates (generally measured at 7:00 a.m.) forstations in the general vicinity of <br />the permit area. <br />Station Distance/DirectionPrecipitation (Inches)* <br />Numberfrom Permit Area <br />9/189/219/229/289/299/30 <br />CO-LP-83.6 mi.E0.502.020.52----0.32 <br />CO-LP-222.1 mi.NNW0.572.130.420.291.160.30 <br />CO-LP-413.3 mi.N0.002.260.47------ <br />CO-LP-592.5 mi.NW0.411.520.550.301.200.24 <br />*--indicates no data reported for that date <br />stnd <br />For all stations, the largest event took place on September 21and 22. The inter-station <br />differences in precipitation totals demonstrate the geographic variability of storm event intensity <br />common to southwestern Colorado. Totals for the two daysrange from 2.07” to 2.73”, with <br />2.47” being the average. (Details regarding what times duringthose days the rain actually fell <br />are not available.)For the Carbon Junction Mine, the 10-year 24-hour storm is 2.25”, and the <br />25-year storm is 2.67”. <br />BACKFILL and GRADING –Rule 4.14 <br />Contemporaneous Reclamation 4.14.1; Approximate Original Contour 4.14.2; Highwall <br />Elimination 4.14.1(2)(f); Steep Slopes 4.14.2, 4.27; Handling of Acid and Toxic Materials <br />4.14.3; Stabilization of Rills and Gullies 4.14.6: <br />Some minor rills have formed on the reclaimed southern slope of the Upper Carbon Junction <br />Channel(Photo 14). The erosion is consistent with what was observed on nearby <br />undisturbed slopes, and does not appear to be jeopardizing the stability of the site nor <br />impacting the post-mining land use. <br />REVEGETATION –Rule 4.15 <br />Vegetative Cover; Timing: <br />The fall rains have encouraged some “greening-up”of vegetation within and adjacent to the <br />permit area. Unfortunately,amultitude ofthistle (mainly Musk)rosettes have sprouted up <br />This <br />along the length of the reclaimed south slope of the Upper Carbon Junction Channel. <br />area will likely requirecontinuous attention throughout the coming years, in order to <br />ensure that the weeds are effectively controlled. <br />ENFORCEMENT ACTIONS/COMPLIANCE <br />No enforcement actions were initiated as a result ofthis inspection, nor are any pending. <br />Number of PartialInspection this Fiscal Year: 2 <br />411 <br />Number of CompleteInspections this Fiscal Year: 1Page of <br />