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MINE ID # OR PROSPECTING ID #: M-1989-147 <br />INSPECTION DATE: 919619008 INSPECTOR=S INITIALS: JLE <br />OBSERVATIONS <br />This was a normal monitoring inspection of the Nyholt Pit; permit number M-1982-147. This site is located <br />four miles south west of the town of Brighton, Colorado in Adams County. I, Jared Ebert of the Colorado <br />Division of Reclamation, Mining and Safety conducted the inspection. Mr. Sean Frisch and Arnie Robert of <br />Lafarge North America accompanied me on the inspection. <br />The permit area is 308.70 acres, and the post mine land use is designated as recreation and water storage. <br />According to Mr. Frisch, mining has been complete at this site and they are in the process of reclamation of the <br />site. Through the mining operation, the operator has created three lined water storage reservoirs that are <br />irregular shape. The pit slopes have been backfilled with shale's, clay and overburden to create the pit slopes <br />and line the reservoir. The reservoir liner was to be keyed into the underlying shale layer of the pit floor. <br />According to the reclamation plan, all the pit slopes for each of the reservoir were to be at a 3:1 horizontal to <br />vertical ratio the entire length of the embankment. According to Mr. Frisch, all the lakes have been lined, but <br />the Office of the State Engineer has not signed off on the liner at this time. <br />North West Lake: <br />Two mined material stockpiles are in place in the lake floor. The pit slopes appeared to be at a 3:1 or less ratio, <br />and were stable at the time of the inspection. Only minor rills were noticed on the pit slopes. Cottonwood trees <br />have volunteered into the pit and on the pit slopes. Several species of annual grasses and forbs have also <br />become established on the pit floor and the pit slopes. Several species that were notices were Cheatgrass, <br />Kochia and sunflower. A road has been constructed between the north west reservoir and the north east <br />reservoir. This road will be paved and will eventually connect to 120th avenue. <br />North East Lake: <br />The slopes of this reservoir appeared to be at a 3:1 ratio or less. Russian Olive and Tamarisk trees have <br />volunteered into the bottom of the pit. Eventually, these trees will be completely submerged with water. <br />However, until this done, these trees my volunteer in other locations of the permit area and outside of the permit <br />area. These trees should be treated and or controlled in order the limit their spread. This is cited as a problem <br />on the last page of the report. Large material stockpiles are in place on the south side of the north east reservoir <br />and many pieces of equipment are located on the east side of the lake. A large gully has formed on the pit slope <br />on the south portion of the lake near the stockpiled material that will need to be stabilized (See Figures 8 &9). <br />This is cited as a problem on the last page of this report. Like the north west reservoir the pit slopes had various <br />species of grasses and forbs established. Several other species of wheatgrass and grama grasses were also <br />observed. <br />South Lake: <br />The slopes of this reservoir varied in steepness. The slopes appeared to be constructed at a 3:1 ratio on the <br />north, east and on portions of the southern reservoir slopes. However, the western pit slope appeared steeper <br />than a 3:1 ratio. The slope was measured with an Abney Level at five locations on the pit slide slopes at 50 to <br />100 yard intervals. The slopes were observed as follows.