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6.3.2 SATELLITE STATION The Satellite station monitoring location is in the western portion of the Stage lA closure footprint and the soil moisture results from this location are illustrated on Figure 9. As with the MET station location, soils at this Satellite station exhibit variations in moisture content that are broadly associated with periods of precipitation events, similarly to those observed at the MET station, with only the more severe events (e.g., winter storm of January and February 2009) causing a discrete soil moisture response. The increasing soil moisture trend observed at the MET station from late summer through fall is also observed at the SAT station. Again,this late summer increasing trend has been observed at other sites and is likely to be the result of the introduction of moisture from the waste. 6.4 HEAT DISSIPATION SENSORS 6.4.1 MET STATION Data from the soil suction instruments (HDUs) installed at the Met station are illustrated on Figure 10, and these trends generally mimic the soil moisture results. As shown therein, soil suction potentials are generally greater (indicating dry conditions) at shallow depth(12-inch) and lower (indicative of a more moist condition) at deeper depths (36-inches). This clearly indicates an upward suction gradient(and an upward moisture flux gradient) from the base of the cover throughout the majority of the modeled years. This condition will result in long-term drying of the final cover and solid waste system over time. A positive (downward) suction gradient was noted at this location during and immediately following storm events (e.g.,January and February, 2009). This gradient reversal represents the only period of time when moisture is expected to have moved downward and in response to soil suction gradients. This condition exists for only a matter of weeks following the most severe individual rain events. For longer duration, repetitive rain events like that observed in late ' February, 2009, soil suctions are below the sensitivity of the instrumentation and the downward movement of water in the cover is likely to be slower and dominated by gravity rather than soil suction. r6.4.2 SATELLITE STATION Data from the soil suction instruments installed at the Satellite station are illustrated on Figure 11 and these data also generally mimic the soil moisture data similar to the observations at the MET station. The Satellite station data exhibit dramatically higher suction potentials in shallow soils and lower suction potentials in deeper soils over a majority of the year. While soil suctions in the total soil profile decline dramatically during the winter, an inverted suction gradient is not well developed, even during the wet winter 2008/2009 year, since all the depths exhibit a suction potential near the minimum measurement capability of the probes. Also of note at the Satellite station, is the fact that soil suction increases (drying of the soils) are less dramatic after the rainy seasons, when compared to the MET station data. Comparison of the vegetation conditions at both the SAT and MET locations indicates that this slower drying trend is likely to be the result of the destruction of or inability of the vegetation to establish itself in and around the Satellite station. GeoLogic Associates