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Memo to Boulay & Berry Bear 111 Landslide page 5 of the North Fork of he Gunnison River. Examination of the upper slope discerns numerous and extensive landslides and debris flows. Approximately 500 feet up slope from the Bear III landslide an extensive complex of debris flows blankets an upper surface. These flows break over the crest and flow down the exposed hillslope in several locations adjacent to the Bear III landslide. Several lazge scale (up to 50 foot high) head scarps bound the up slope terminus of these flow complexes. Older flow deposits mantle these head scarps in at least one location. The superposition of these deposits provides insight into the sequence of their formation. Examination of the 1980 aerial photography determined that the hillslope had apparently been stable for at least several centuries. In the area of the landslide in excess of one toot of multiple horizoned humic topsoil covers the slope uniformly. This soil mantle may have taken several millennia to develop. Mature trees and scrub Oak veneer the slope. Grass and scrub oak covers the majority of the North Fork valley side slope with the exception of several rock ledges. During the El Nino year of 1983 slope failure at this site resulted in extensive damage to the fan portal facilities at the Bear III mine. The extensive flow complex up slope From the Beaz III slide was reactivated at that time. Subsequent landslide and debris flow events have occurred repeatedly during the past 14 yeazs. Aerial photographic evidence suggests that the headscarp of the modem debris flow complex may represent a penetrating failure plane of an older large landslide. This larger landslide may have involved bedrock beneath the colluvia] cover. The juxtaposed debris flow deposits which cross and cover this large scarp may provide evidence relating to the length of time this scarp and landslide have remained relatively stable, The muted form of the flow deposits, the maturity of soil and grass cover, and the lazge size of mature conifers suggest that this scarp and large landslide, if it exists, have remained stable for a minimum of several centuries. During our field examination on Febmary 10, 1998, both Bruce Stover and I attempted to examine portions of this upper scarp and mudflow complex which I hypothesize might provide telltale evidence to verify or refute the existence of lazger, deeper-seated failure planes. Snow cover and field conditions prevented us from completing the necessary examination of the suspected telltale locations. Conclusion It is my opinion that the November, 1997 landslide which occurred adjacent to the recently reclaimed Bear III mine portals was initiated by groundwaters emanating from the bedrock beneath the failed colluvium. Observations of the slope geomorphology, stratigraphy of the colluvia) deposits, and pedologic development suggest that the initiating groundwater discharge is a new phenomena or changed condition, which has not been occurring for any significant