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4 1 1 LJ }It is difficult to understand the saturation of surficial soils above the boring P1; a fairly large landslide has developed at this location and it was fully saturated during the first weeks of July although the area above the slide was very dry on the surface. It can be concluded that hydrological conditions as they have been encountered during the spring and early summer of 1980 appear to be very unfavorable and they cannot be well understood. We recommend that as a minimum, ground water monitoring in existing piezometers be systematically performed during the re- maining part of 1980 to obtain some more reliable data for the proposed construction development. 2.2 SLIDES EXTENT AND CHARACTER During our field mapping program, an area was delineated at the property that probably comprises the extent of the old landslides. An accurate delineation is very difficult and in our opinion, not necessary for the purpose of this study. The deline- ation agrees generally with the work by IECO referenced earlier. The extent of the slide area is shown on Plate 1 - Geotechni- 'i cal Map. The slide area is located approximately in the central apart between Sylvester Gulch and the unnamed creek on the west I jside of the property; on the south side, it is limited by a distinct flat bench extending at the elevation of 6,640 and higher. On the north side, the slide area is limited by the d ower distinct bench at an elevation of 6,300 and lower. In addition to the slide extent, the geotechnical map shows !some geotechnical and morphological features related to land- I islides and general stability conditions. It shows areas that are apparently free of old landslides; it shows minor flat benches or flat landslide portions. It shows steeper slope portions that may 'comprise old slides scarps or slide toes. Several recent slides that developed on the site either this year or several years ago are shown as well. cc«'wo coHwrna nc