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September 15, 2010 C-1992-080/Carbon Junction Mine <br />all disturbed areas. <br />AVAILABILITY OF RECORDS - Rule 5.02.4(1): <br />All required records were on file at the office of Goff Engineering (see attached list). <br />BACKFILL and GRADING - Rule 4.14 Contemporaneous Reclamation 4.14.1; Approximate Original Contour <br />4.14.2; Highwall 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 />Backfilling, grading, topsoil replacement, and revegetation appeared to have been completed in all areas <br />within the permit area except boreholes 17-1, 94-1, and 95-1. (Two low areas where collection ditches have been <br />regraded in the area of the gravel pit/coal permit boundary are being researched). Topsoil stockpiles 4 and 7 were <br />approved as permanent features in June 2010 (TR-16) based on their compatibility with the surrounding <br />topography and previous achievement of the required minimum replacement thickness of one foot of topsoil on <br />reclaimed areas. <br />HYDROLOGIC BALANCE - Rule 4.05 Drainage Control 4.05.1, 4.05.2, 4.05.3; Siltation Structures 4.05.5, <br />4.05.6; Discharge Structures 4.05.7, 4.05.10; Diversions 4.05.4; Effluent Limits 4.05.2; Ground Water <br />Monitoring 4.05.13; Surface Water Monitoring 4.05.13; Drainage - Acid and Toxic Materials 4.05.8; <br />Impoundments 4.05.6, 4.05.9; Stream Buffer Zones 4.05.18: <br />Pond 1 (large pond, outfall 001). The two sediment control ponds were approved for removal in <br />Technical Revision 15 (approved in January 2008) and MR-6 (vegetation cover data, approved August 11, 2008). <br />Pond 1 (the large pond) was regraded in early 2009 and backfilled with all of the material from stockpile #8. <br />Regrading resulted in a flat surface that blends well with the adjoining flat, tilled farmland just outside the permit <br />area to the south. Ditches that fed Pond 1 have also been regraded. Runoff from this large flat area would make <br />its way to natural drainages on either side of Ewing Mesa, in the same way that runoff from the farmland would <br />naturally drain. <br />Pond 2 (small pond, outfall 002 ). Pond 2 also was regraded in early 2009, with the earthen embankment <br />removed, leaving a flat-bottomed drainage that reports a short-distance to the lower part of Carbon Junction <br />Canyon. Runoff from the west half of the PRSA will continue to flow through this drainage to Carbon Junction <br />Channel, via a culvert underneath the permanent asphalt-surfaced haul road. <br />Carbon Junction channel. The reconstructed section of the Carbon Junction channel was in good shape, with the <br />exception of a hole apparently caused by erosion at the inlet end of the riprapped segment of the channel. The <br />hole is about 10 feet deep and 6 feet in diameter. The hole formed in the outside bend of the reconstructed <br />channel where the upstream unlined section of the channel adjoins the downstream rock rip-rapped section of the <br />channel. The wall of the hole on the outside bend of the channel is a steep-faced cutslope that is not readily seen <br />when approached on foot from the south, and consequently may be a safety hazard. The rock rip-rapped section of <br />the channel downstream from the hole showed no evidence of high flow rates, as riprap was in place and only a <br />small amount of sediment was found on the riprap. The two 5 '/2 -foot diameter culverts that extend underneath <br />the paved haul road at a location a few hundred feet downstream from the hole contained little sediment. The <br />possibility that flow from the hole piped into the subsurface could not be determined because boulders covered the <br />Number of Partial Inspection this Fiscal Year: 2 <br />Number of Complete Inspections this Fiscal Year: 1 <br />Page 3 of 10