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L • • were produced. However, without closer examination of the rocks themselves and the slope it could not be determined whether the rocks were in fact recent or were due to older rock falls Trom surraund~ng cliffs. The next stage of the investigation involved a detailed examination of the drainage from the Phase ] mining limit boundary to the bottom of 4lilliams Canyon. This was accomplished by climbing down the drainage and photographing the various rocks, examining existing vegetation and vegetation regrowth around the rocks, comparing light colored with dark colored rocks, and noting other points which could provide an approximate date as to when the rocks arrived at their location. Near the top of the drainage a number of moderate to large rocks were noted just below the mining limit but at least 200 feet inside the permit boundary. These rocks were already kno.,n to exist and when Phase 1 nears completicn it was planned to remove these rocks and any trees which had died as a result of damage. One very large, old rock (indicated by the dark gray color and the grass growing in cracks) on the side of the hill was noted to have a drill hole in the Sider of it. However, the dimensions of the hole was too small to have been produced by Castle Concrete. Therefore, it appeared this large rock had fallen to this location during previous mining, probably during the 1930's when excavations occurred abovea this area. 1t became clear, as a result of this find, that at least three elassers of rocks w~xald be found. The first class would be boulders which had naturally fallen from cliffs as a result of weathering. The second class of rocks weld be those wf~ich had originated from the old mining operation. The third class of rocks were those which had more recently fallen into the drainage as a result of mining in Phase L. These three classes would need to be distinguished in order to classify the r~x ks in the drainage and determine the extent of the recent spillage, which b:~ this point in the investigation was realized to be likely, to at least some extent. Further down the drainage, five large rocks which had come from the Phase 1 area were noted. As judged by the color, these rocks were of regent origin and, as shown by small disturbances in the soils above each rock location, it could be determined that they had come it om the Phase 1 area. H7wever, as shover, by the lack of anything more than minor damage to the soils and hillside vegetation, it became apparent therse rocks had been rolling rather sl wly. Cne rock was rolling so slowly it became lodged partially underneath a rack of comparable size wnich had been there 1 mg enough to develop grass in cracks and even a small shrub growing out the top of the rock. All but two of these rocks were noted as being totally within the permit COf3~CTIVE A,TICN PLAN SNYDc-R ROCK 4ILL5 PAS 2