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III. COMMENTS -COMPLIANCE <br />Below are comments on the inspection. The comments include discussion of observations made <br />during the inspection. Comments also describe any enforcement actions taken during the inspection <br />and the facts or evidence supporting the enforcement action. <br />General Comments <br />This was a partial mine site inspection, with a focus on permanent drainage channel reconstruction and <br />maintenance in the reclaimed portions of the original permit area (final grading and channel construction has not <br />yet been completed in the South Extension portion of the permit area). The drainage channel inspection was <br />initiated on the morning of October 6, with the assistance of Mike Boulay from the DMG Denver Office. The <br />drainage channel inspection/evaluation was not completed, and will likely be completed over the course of one <br />or more additional inspections this fall or next spring. Measurements and observations pertinent to the drainage <br />segments inspected on October 6 are presented in this report. We were not accompanied by an operator <br />contact during the detailed channel inspection. <br />On the morning of October 7, I conducted a general partial inspection, accompanied by Roy Karo of SCC. <br />W Bather was clear and cool during both days of the inspection. Ground conditions were moist to muddy, due to <br />significant precipitation earlier in the week. <br />Permanent Drainage Channel Inspection <br />Drainage channels inspected were 005-E1 and 005 Gulch channels in the "D" and "C" Pit reclaimed areas; and <br />006-NE4 and 006-NE1 in the "B" Pit reclaimed area. Cross section measurements were taken at various <br />locations by stretching a transect tape across the top and base of channel to measure width; depth was <br />measured with a hand tape measure, from the channel bottom to the horizontal transect tape stretched over the <br />top of the channel. The channels were walked from upstream end to downstream end. Slope measurements <br />were taken using an inclinometer, siting to eye level on the second inspector, standing in the same position in <br />the channel cross-section, at the opposite end of the measured reach. A number of photos were taken with a <br />digital camera to document observations and supplement measurements and descriptions. <br />Digital image labels, brief description of location and site characteristics, and applicable measurements are listed <br />below: <br />005-E1 Channel <br />02221 -Low gradient upper reach. This is a stable vegetated channel reach, that appears to conform <br />with approved design configuration, with excess capacity. <br />02222 <br />02223 -Steep reach of channel upstream of 005 Gulch Confluence. This is a stable riprapped reach <br />with adequate capacity, 17% gradient (within design limit). Typical BW = 10', TW = 17.5', D = 1.0', <br />exceeds design capacity. There is an old scraper route from the Ridgeline Road to the channel along <br />this segment that is rilled and needs to be reclaimed. <br />005 Gulch Channel <br />02225 <br />02226 -Steep upper reach with rock checks installed as alternative to riprap. Rills developing between <br />rock checks, with piping erosion evident beneath several of the check structures. <br />02227 -Lower segment of reach with rock check structures. Rills up to 12 inches deep in some <br />locations. Channel gradient through the reach with rock checks is 14% - 16% (within design <br />specifications), and channel capacity exceeds design for the grade. The rock checks as installed may <br />not be functioning as an effective alternative to the 6" riprap originally specified. <br />3 <br />