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Memo to Boulay & Berry Bear III Landslide page d July, 1997, in addition to my personal knowledge and experience in the immediate area, provides me with an understanding of the mass wasting character of the immediate vicinity of the landslide. The Bear III mine permit area has been characterized by frequent and extensive mass wasting events since 1983. The Bear mine portals and portal fan were damaged by mudflow events on several occasions. Rotational landslides have damaged the portal access road and portal bench on several occasions. The valley slope above the landslide under consideration evidences several large ancient scarps and an extensive mudflow complex. The W WE report maps delineate numerous large, open scarps and tension fractures above the active landslide. Several of these landforms have been active as recently as 1996. If precipitation was abnormally high throughout 1997, as W WE postulates, it seems likely that other recently active landslides and mudflows would have been reactivated. None of the nearby mass wasting sites exhibited any activity during the summer or fall of 1997. (3) Bruce Stover and I observed wet areas adjacent to and on the upper portions of the landslide mass on Febmary 10, 1998, as described above. The moist to saturated azeas described within the extensional trough a[ the head of the landslide were unfrozen, even though the ambient air temperature was approximately 20° F at 8:30 am. The moist area was devoid of snow, in contras[ [0 6 to 18 inches of snow retained on much of [he adjoining slope and landslide mass. Warm water vapor was issuing from the base of the scarp, appazently from the C-Seam subcrop. This wet to saturated condition persisted along about the eastern half of the scarp tojust below where a large boulder had fallen several days before the slide occurred. West of this point the main scarp trough was frozen and snow covered. If W WE postulates that this tnoisture represents infiltrated precipitation, why is it still apparent two months after the failure? Why has the ground temperature remained sufficiently elevated to preclude ground frost? Based upon these observations it appears more plausible that the waters which initiated movement in the upper eastern portion of the landslide mass issued from the bedrock strata beneath the colluviunt comprising the failed landslide mass. In addition, the fact that the moist and saturated areas within [he extensional trough and adjacent to the reclaimed Bear II mine western-most portal were not previously observed by WWE suggests that warm groundwaters have continued to enter the landslide mass, eventually wetting enough of the overlying and adjacent soil materials to result in the formation of the warm, saturated areas we observed on Febmary 10, 1998. Geomorphology of the Hillslope The modem landslide under consideration occupies a landscape with numerous mass-wasting artifacts. The subject landslide occupies the toe of the north facing valley sideslope of the valley