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0931 The northern portion of NOSR 1 is drained by East Middle Fork Parachute Creek. This stream flows westward with a gradient of approxi- mately 180 feet per mile and includes two major tributaries - Northwate~ Creek 'and Trapper Creek. The headwater areas for these tributaries are relatively broad valleys which gradually narrow downstream. Valley-ridge relief in the upper half of this watershed is about 400 feet. This relative relief increases to 600 feet near the Trapper-Northwater conflu- ence and to more than 800 feet where East Middle Fork Parachute Creek crosses the western boundary of the Reserve. 3.3 CLIMATE The climate on NOSR 1 can be generally characterized as high altitude, semi-arid. Annual precipitation, as monitored since November of 1976, has ranged from a low of about 12 inches in 1977 to a high of more than 25 inches in Water Year 1980 (October through Septemberl. The existing data indicates that in excess of 60 percent of total annual precipitation is in the form of snowfall. Temperature varies from a summer daytime high of about 320C (900F), to a winter low of about -28oe (_180Fl. Because of the short period of record, these values may not be representative of normal conditions. However, they are the best area-specific values available. 3.4 VEGETATION Principal vegetation communities on NOSR 1 include upland sagebrush, mixed mountain shrub, and aspen/douglas fir forest (Cook, 1974). Each of these communities are localized according to various physical factors including: elevation, slope, aspect, soil type, and soil moisture. For example, the douglas fir forest community is found only on-steep, north- facing slopes. A detailed description of the vegetation on NOSR 1 is included in the Environmental Baseline Characterization of the Naval Oil Shale Reserves (TRW, 1982l. 3-3