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Memo to Boulay & Berry Bear III 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 Beaz III landslide an extensive complex of debris flows blankets an upper surtace. These flows break over the crest and flow down the exposed hillslope in several locations adjacent to the Bear III landslide. Several large scale (up to 50 foot high) head scarps bound the up slope terminus of these tlow 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 Itillslope had apparently been stable f'or at least several centuries. [n the area of the landslide in excess of one foot of multiple horizoned humic topsoil covers the slope uniformly. This soil mantle may have taken several millennia to develop. ivlature 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 EI 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 Bear III slide was reactivated at that time. Subsequent landslide and debris tlo~v events have occurred repeatedly daring the past lA years. 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 colluvial cover. T'he 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 large 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 February 10, 1998, both Bruce Stover and 1 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 larger, 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. 19971andslide which occurred adjacent to the recently reclaimed Bear III atine portals was initiated by grouttdwaters emanating from the bedrock beneath the failed colluvium. Observations of the slope geomorphology, stratigraphy of the colluvial deposits, and pedologic development suggest that the initiating groundwater discharge is a new phenomena or changed condition, which ltas not been occurring for any significant