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Attachment II <br />• HA[Iffl>nl1D C~ICATIQI STATFI+IIrMS <br />B. Haal Road <br />- Grade and Alignment <br />Sun Coal Company located, designed and located the access road in <br />accordance with CMLRD's approved permit (T6-61) using standard mine <br />engineering principles. The road alignment was chosen based on the <br />location of established farm aid exploration roads, geotechnical stability <br />studies, and acceptable road truck haulage grades. Road grades varied <br />from 3.0 to 9.5 percent with an average grade of 6.3 percent. Straight <br />portions of the road were cx~owncd about 6 inches in the middle and turns <br />aryl switch backs were sloped to allow surface water runoff to be conveyed <br />to the the inside ditch. A berm of at least 3.5 feet in height, with 1.5 <br />to 1.0 horizontal to vertical slopes were located along all outslopes. <br />An acres, road geotechnical study was conducted to attest to locate the <br />access road in geotechnically stable areas. The study, "Geotechnical <br />Investigation - Sun Coal Co. Meadows No. 1 Mine, Milner Colorado" prepared <br />by Robert W. 11~eon, was submitted to Slur on July 12, 1977. The purpose <br />of the study was to delineate surface and subsurface conditions for the <br />proposed haul road. The report addressed haul road construction problems <br />and identified areas where instability could occur. The Robert W. <br />• Thompson report states the lower portion of the road "shows little <br />tendency towards slope instability" and the upper portion of the road <br />above Culvert 6 "will require substantial cut and fill operations to <br />produce a satisfactory road. ...where there are numerous recent and <br />ancient landslides". The Robert W. Thanpson report assumed: <br />- the road was designed to support loaded rear dump trucks with <br />payloads ranging from 25 to 30 tons; <br />- maximum grades on the order of 8 percent; <br />- road alignment must fall within a corridor which lies 50 feet to <br />either side of the existing access road alignment; <br />- the road surface to be aporoxLnately 50 feet of right-of~ray con- <br />taining a 3-foot berm on the outside edge and lateral drainage <br />ditch to the inside; <br />- the actual read surface was to be approximately 30 feet wide with <br />an inslope road grade of 2 percent. <br />The road was constructed in 1977 and based on a field reconnaissance <br />survey in 1981, the road appeared to have been constructed using these <br />. design guidelines. <br />- 210 - (Rev. 5/86) <br />