2018-12-11_INSPECTION - M1991075

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PERMIT#:M-1991-075 INSPECTOR'S INITIALS:AME INSPECTION DATE: October 11,2018 OBSERVATIONS This was a normal monitoring inspection of the Barnes Pit (Permit No. M-1991-075) conducted by Amy Eschberger of the Division of Reclamation, Mining and Safety(Division). Mr. Allen Watts represented the operator during the inspection. The site is located approximately 16 miles southeast of Sheridan Lake, Colorado in Kiowa County. Access to the site is from the west off Co Rd 76. Photos 1-10 taken during the inspection are included with this report. This is a 112c operation permitted for 48.5 acres to mine sand and gravel for use in county road construction and maintenance (see enclosed mining plan map). No material processing occurs on site. Mined material is directly hauled off site for use or temporarily stored on the pit floor until needed. The approved permit area is rectangular in shape, and includes a segment of an unnamed drainage at its northern end. The operation began mining from an existing pit located at the northern edge of the permit area, expanding it generally southward. Salvaged topsoil will be stored at the eastern edge of the pit for use in reclamation. The approved post-mining land use for the site is rangeland. Reclamation of the site will include grading all disturbed slopes to 3H:1 V or flatter, replacing 12-36 inches of topsoil on disturbed land, and seeding the land with a native grass seed mixture. The site was not active during the inspection. However, according to annual reports submitted by the operator, the site is active every year. A permit sign was posted at the main site entrance. The corners of the permit boundary were delineated with T-posts. The operation has disturbed approximately 17.5 acres in the northern half of the permit area, south of the drainage. The edges of disturbance are very close to the western and eastern boundaries (see enclosed Google Earth image of site). The highwall is approximately 20-25 feet in height with near vertical slopes, and daylights to the north. Portions of the western highwall have been graded to 3H:1 V and have some vegetative cover consisting of native grasses and annual weeds. Mined material was stockpiled on the pit floor. Topsoil was stockpiled along the eastern edge of the pit. Some ponded water was present on the pit floor during the inspection due to a recent storm event. The operator should be aware, the Division of Water Resources requires that all stormwater contained on site either infiltrate into the ground or be released to the natural stream system within 72 hours, or all work must cease until a Substitute Water Supply Plan or Augmentation Plan is obtained. At the northwestern edge of the site, the operator has constructed a berm to separate the pit from the adjacent drainage. The drainage is typically dry, flowing only during large storm events. Water was present in the drainage during the inspection. The operation has had issues with the drainage flow overtopping the berm and entering the pit during high flow events. Mr. Watts indicated the berm was recently raised four feet higher to help prevent this from re-occurring. Additionally, the operation is backfilling the northwestern corner of the pit as overburden is made available to reduce the slopes and extend the berm southward from the drainage. The Division observed some erosional rilling and a few gullies along the northwestern pit wall which has steeper slope gradients. Backfilling this portion of the pit should resolve the erosion issues observed. Once the operator has completed backfilling this area, the Division recommends the operator retopsoil and seed the western highwall and any other disturbed areas that will not be redisturbed as soon as possible to help stabilize these areas and prevent weed growth. The operation appears to be following the approved mining plan. No problems were observed. This concludes the report. Page 2 of 8