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001019 PRECIPITATION The winter of 198!/84 and the spring of 1984 experienced much higher than normal precipitation. Summer '84 was rainier than normal. Last fall was particularly significant with unusually heavy snowfall in october and November before the ground had frozen. Snow course measurements for October and November were unusually high for the area, As this heavy snowfall melts. it soaks much more deeply into the ground than later snowfalls after the ground has frozen, Unusually large and more numerous occurrences of freezing groundwater springs issuing from normally dry cliffs. road cuts. and hill slopes have been observed in several locations along the 1-70 corridor. This weather pattern and evidence of abnormally high water saturation increases concern because higher water saturation reduces the structural strength of soil and rock. reduces the friction along failure surfaces, and increases the weight of the material increasing the driving forces for a slide, This is also similar to the weather and precipitation events which preceded the Thistle. Utah slide, " " Figure 1 illustrates the annual precipiation at the Climax and Eagle weather stations. The Eagle data closely approximates the Minturn area, Precipitation in 1984 was higher than that previously recorded, Summer precipitation in Figure 2 is also the highest on record, In both cases. averages have been increasing the last three years resulting in the highest departure from average on record. This has caused a super soil saturation condition, Additionally. early snows prior to ground freezing in the fall of 1984 have increased the saturation level, As of April 1. the snow survey by the Soil conservation Service indicated that snow levels at Shrine Pass are 70 percent of last year. vail Pass at 81 percent and Pando Pass at 70 percent of 1984. I' ,.. "