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5.3 AIR TEMPERATURE Over the 1-year monitoring period,the site exhibited an average daily temperature of approximately 60.95'F, with a maximum temperature of 106°F experienced on July 5, 2007, and a minimum temperature of 21.7°F experienced on January 16, 2007. Figure 7 illustrates the temperature trends observed at the on-site weather station over the current monitoring period. For comparative purposes,between 1988 and 2006 the average air temperature measured at the Manteca Station was 60.4°F. 5.4 WIND The average daily wind speed and direction observed and recorded at the on-site weather station during the first year of monitoring was approximately 5.3 mph to the west- northwest(Figure 8 and Figure 9). As shown therein,wind direction often shifted from a west-northwest to the east-southeast direction during.the winter(October to February). Wind speeds measured at the Manteca Station average 4.63 mph to the west-northwest over the period of 1988 through 2006. 6.0 MONITORING RESULTS To illustrate relative changes in alternative final cover soil moisture content over the first year of monitoring,Figures 3 and 4 illustrate soil moisture content and rainfall over time at each monitoring station. 6.1 GENERAL The most significant soil moisture pattern observed at each probe location is the rapid drying trend that develops soon after each wetting event. This drying trend creates a strong upward capillary gradient through the soil profile during most of the year indicating that water at the surface is evaporated directly from the soil. This effect combined with deeper plant evapotranspiration creates an environment where dramatic upward migration of water from the soil cover and waste exists over a majority of the year. 6.2 SOIL MOISTURE 6.2.1 MET STATION The Met Station monitoring location is located in the eastern portion Stage I closure area and the soil moisture monitoring data from this station is summarized on Figure 3. As expected, soils at this location exhibit variations in moisture content that are broadly associated with periods of precipitation events with only the more severe events (e.g., late February, 2007) causing a discrete soil moisture response. An increasing soil moisture trend is also observed at this location during the early summer of 2007 when little or no rainfall has been recorded. This summer to fall increasing trend has been observed at other sites and is likely to be the result of the 5 Geologic Associates