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, \ ~ 003327 that had been i nsta 11 ed by CDOH on the sma" er "hi ghway" 1 andsl i de a few weeks earl ier, The remainder of the EDM points 'on Meadow Mountain were installed as fieldwork and the drilling program progressed, and by mid-July a total of thirteen had been installed on the larger slide feature, The first three were carefully located to ensure that if any large-scale movement of the intermediate landslide were 'to occur it would be immediately apparent, Later in the investigation an inclinometer was placed immediately above the headscarp of this slide near EDM point 2a at drill hole 8, Higher upslope, in the apparently less active part of the Meadow Mountain landslide, we eventually installed 10 more EDM points. Some of these were placed where localized landslide movement was suspected or where if it were to occur it might be the precursor to large scale mass movement of the entire Meadow Mountain landslide. The higher numbered ones 'were located simultaneously with drilling and were based on field observations obtained while drilling was in progress, From the monitoring that was subsequently done little movement in the higher area was detected and that which was seen is probably attributable to shallow earth flowage or instrument noise, However, by the time monitoring of most stations had begun, virtually all of the snowpack was gone and the ground had dried considerably, Such localized earthflowage was suspected but not demonstrated in many places on Meadow Mountain until the drilling program was well underway and considerable fieldwork had been done. In the highest parts of the MeadOW Mountain landslide. above all drill holes and EDM points, older landslide material is covered by glacial drift, mostly bouldery gravels, Even though this area has the geomorphic form of a major. landslide, there is no field evidence whatsoever for deep seated modern movement and I suspect that there has been none, except for small very localized slumps, The upper part of the Meadow Mountain landslide was glacflted by valley glaciers that originated in the Grouse Creek drainage basin<twhere such deposits are abundant, The details of the data obtained from drilling,will be included in the final report, but the essentials of what was learned from this and field data can be summarized as follows: 1, The basal landslide surface of the major Meadow Mountain landslide varies in depth from approximately 90 to 160 feet below the ground surface with numerous bedrock shear zones present above the basal shea r , 2. This basal shear surface occurs at different places within the Belden Shale or in the Minturn Formation; it is mostly in the Minturn Formation on the north side of the landslide, This conforms to the local structure in bedrock. as bedrock bedding has a steep , component of inclination (dip) valleyward, - 5 -