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Memo to Berry/Boulay Jumbo Mountain Landeliding page 2 Dames and Moore further observed; "There is no evidence of current instability on the lower, bench portion of the landslide. In fact, the lack of any surface evidence of past movement indicates that this area has been stable for a long period. Scarps up to 12 feet high are present in the upper, steeper south part of the landslide mass as shown on figure 1. These scarps indicate recent movement. The largest of these scarps are evident on both 1974 and 1992 aerial photographs. This indicates that sliding is occurring slowly - probably less than one foot per year of overall downslope movement." My examination of the recent cracking and landslide movement which has occurred does not refute any of Dames and Moore's conclusions. Examination of 1996 Landslide Deposits Approximately 30 to 50 acres of the SW1/4 of Section 24 has been affected by recent landsliding. Mr. Mautz reports that minor cracking was noted by his ranch hands on the roads within the affected area in the fall of 1995, followed by extensive landsliding in May / June of 1996. This is in keeping with my observations of annual spring/summer landsliding in the North Fork Valley over the past 17 years. Cracks and graben-like (steep-sided trapezoidal) extensional troughs up to ten feet wide and five feet deep were examined in several locations towards the middle to lower portions of the landslide deposit. The more common features are cracks 3 to 12 inches in width. Cracks can be traced for lengths in excess of 100 feet. Most cracks evidence translational offsets indicative of downslope and lateral movements. Cracks occur along contour, parallel to the fall line, and at random orientation. No discrete conclusions could be made about the actual depth of the basal failure plane of the landslide mass(es). The features I observed are typical of large landslide masses in the Williams Fork formation. These landslides occur prolifically throughout the North Fork Valley on slopes of varying gradient and aspect. The largest and most notorious active landslide in the area is the Muddy Creek Landslide, east of Paonia Reservoir. The immediate area of the rejuvenated landslide movement is grossly headed by the large (up to 50' vertical relief) headscarp mapped by Dames and Moore in their 1993 report. The active landslide mass appears to be approximately 1,600 in length between approximately the 7450-foot and 7150-foot elevation contours. While numerous extensional cracks were examined, I did not discern a major compressional zone, but our logistics did not allow me to examine the lower third of the landslide where I would expect compressional features to predominate. Norm Every of MCC, who has examined this area recently, did not recollect a significant compressional or overrun area. Translation of the sliding debris can be