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<br />• <br />• <br />Future movement is predicted using the log-log plot of historic movement, and extrapolating the movement <br />to the future as shown on Figure J3. Figure J3 shows that the all portions of the landslide have stabilized, <br />and have reached zero movement. <br />J5.2 Piezometers <br />Historic piezometer levels are used to establish the general groundwater flow pattern and hydrostatic heads <br />for use in stability analyses and evaluating effectiveness of dewatering activities. Graphs, showing historic <br />water levels for piezometers, are provided in Appendix J2. Plan locations of the piezometers aze shown on <br />Figure I1 of the 2000 Addendum. Table J1 shows response of piezometers during the 1998, 1999, 2000 <br />and 2001 spring seasons. <br />Table J1 indicates that water levels, in the spring of 2001 and at the head of the slide, rose at a smaller <br />amount than in the Spring of 2000. <br />Overall water levels in the head and body have declined on a yeaz to yeaz basis since 1999, indicating slow <br />drying of the slide mass and improved drainage of water. <br />To evaluate the effect of climate on the water levels observed, rainfall and runoff data was reviewed for the <br />1997, 1998, 1999, 2000 and 2001 seasons. Figure J4 shows that in 2000 rainfall amounts were lower than <br />average and lower than rainfall amounts experienced in the last 9 years. Figure JS shows that in 2001, <br />dischazges to the North Fork of the Gunnison declined for the fourth consecutive yeaz, indicating smaller <br />snow pack and less runoff. It can be concluded that smaller amounts of rainfall and runoff in part <br />contributed to reduced water levels in the landslide mass, and greater landslide stability. <br />J5.3 Inclinometers <br />Historic inclinometer movements are used to establish the shear plane and rate of movement at the shear <br />plane of the slide. Graphs showing inclinometers and historical inclinometer movements are provided in <br />Appendix J3. Plan locations of inclinometers aze shown in Figure Il of the 2000 Addendum. <br />Barr Enplneerlny Company <br />PCDOCSt230503/CAK <br />December 15, 2000 <br />10 Appendl: J <br />2007 Addendum to <br />1997/98 Landslide Corractlve Measures Report <br />