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Evaluation of Bear No. 3 Mine Landslide <br />' A CDMG photo (February 1994) shows that the two active upper landslides had then <br />grown to almost the same size as in July 1997. <br />' In Mazch and April 1996, a series of landslides and debris flows destroyed the Bear fan <br />' house and damaged the access road. One slide east of the fan moved 59 feet north in one <br />surge. The toe of the slide encroached two-thirds of the way across the Nort}! Fork. <br />A CDMG photo (December 1996) shows that the eastern raveling slope has begun to <br />develop. <br />A CDMG photo (February 1997) shows further development of the east raveling slope <br />and the two active upper landslides. <br />Discussions with CGS personnel traveling and working in western Colorado indicated they had <br />noticed a higher than normal number of new landslides and renewed slide activity in the summer <br />of 1997. Richazd Dunrud, afrer his August field trip to the azea, said that he had noted an <br />unusually large number of fresh scarps and slides. Recent discussions by John Rold with Federal <br />Highway Administration personnel on matters unrelated to this slide indicated the summer of <br />1997 was a bad season for them in terms of landslides. <br />1 Bear Coal Company's response (December 19, 1997) to CDMG questions stated "The slide <br />started in June 1997 with activity on the west side where rocks were raveling in the river. The <br />slide progressed from west to east. Slide activity increased in October with cracks noted west of <br />the Bear's C-Seam portals. On November 14 and 15, 1997, slide activity increased dramatically. <br />On November 1Th, water emerged from the eastern slide scarp." (Field inspection and photos <br />show that the water emerged some 30 to 40 feet to the east of the active slide area.) <br />Field inspection by WWF, personnel (Dave Jubenville on November 20 and John Rold on <br />1 December 2 and 3) and photo comparisons indicate the slide has changed little since its surge on <br />1 November 14 and 15. <br />] 831-032.411 Wright Water Engineers, Inc. Page 6 <br />