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Subsidence Evaluation For <br />Exhibit 60 The Apache Rocks And The Box Canyon Mining Areas Page 22 <br />• field inspection in October 1996, water may be flowing beneath the road grade of State Highway <br />133. According to Bob Barrett, Grand Junction District Geologist for the Colorado Department <br />of Transportation (CDOT), a drainage system (cobble and geotechnical fabric) was installed <br />within the drainage azea of the unnamed drainage west of Box Canyon to channel the numerous <br />springs that were encountered during highway construction in 1980 (oral communication, Bob <br />Barrett to John Rold, November 14, 1996). The reported springs encountered during <br />construction of Highway 133 are thought to reflect flows emanating from the Oliver No. 2 Mine. <br />In addition to observations of flows from the Oliver No. 2 Mine portal in the 1970s, additional <br />observations, were made regarding surface flows in the Sylvester Gulch drainage. One particular <br />observation, (Bill Beaz oral communication, 1972) was that there was a substantial decrease in <br />surface flow (and dewatering of a beaver pond) from the first east fork of Sylvester Gulch above <br />its confluence with the North Fork. There has been speculation that this appazent decrease in <br />flow was the result of Oliver No. 2 mining activities, however, the reported decrease in the flow <br />during the 1970s is puzzling for two reasons: <br />The healing and sealing potential for stream channels discussed in Section 2.05.6 conflicts <br />with short-term stream diversion not to mention stream diversion after 20 years; and <br />2. No water was observed upstream from the area where the beaver ponds were located, beyond <br />• where the Oliver No. 2 mining could have had an impact. Consequently, there was not a <br />perennial flow for the beaver habitat in the canyon when the author observed the beaver <br />ponds in the mid-1970s. It is not known what happened to the source of water to the beaver <br />ponds; the beaver had already moved out. <br />MCC now owns the water right to the first east fork of Sylvester Gulch-the water right <br />previously owned by the Beaz family. Therefore, the puzzling decrease in flow (perhaps the flow <br />was intercepted by a permeable formation or natural fractures exposed by stream erosion) should <br />only concern the current owner of the water right. <br />8.3 Methane Concentrations in the Oliver No. 2 Portal Area <br />Methane was also encountered in the portal area of the Oliver No. 2 Mine during exploration <br />drilling for the State Highway 133 road bed. Boyd Emmons, State Coal Mine Inspector, stopped <br />drilling in one hole north of the Oliver No. 2 portal when 100 percent methane was detected. It <br />was 14 to 15 days before CDOT could remove steel from one hole (Boyd Emmons, oral <br />communication, Nov. 6, 1996). According to Emmons. methane still is likely to be present in <br />the roadbed. <br />L.I <br />831-032.181 Wright Water Engineers, Inc. <br />