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the second year moisture monitoring report, a re-calibration of the sensors was conducted and for this third year of data collection the same calibration settings have been used for this monitoring period. The Gee Passive Capillary Lysimeters were installed at the base of the cover system in order to evaluate moisture migration through the cover. In addition to the lysimeters, soil moisture probes and heat dissipation units were installed at 12", 24"and 36" depths below the ground as shown on Figure 2. 5.0 DEMONSTRATION PROJECT CLIMATIC CONDITIONS Climatic conditions at the Forward Sanitary Landfill Stage 1 final cover area are considered to be semi-arid and are characterized by wet winters and humid temperate summers. The following sections summarizes regional climatic conditions as well as the climatic conditions recorded ' from the on-site meteorological station located at the MET soil moisture monitoring station (Figure 1) during the approximately three year monitoring period. 5.1 RAINFALL Local historical average precipitation records from the Manteca California Irrigation Management Information System (CIMIS) Station(less than 4 miles from the site) indicate an average annual precipitation of 13.22 between 1988 and 2006. Total measured rainfall at the on- site MET station was approximately 24.12 inches over the three year monitoring period, of which, 9.16 inches fell during this past third year(Figure 3). 5.2 EVAPORATION Potential evapotranspiration measured at the Manteca station averaged 54.12 for the three year monitoring period, and was measured at 52.19 inches over the last year. Historical potential evapotranspiration recorded at the same station averaged about 51.03 inches from 1988 through 2006. 5.3 SOLAR RADIATION The mean daily solar radiation at the on-site MET station averaged about 420.60 Langleys during the most recent monitored year. Similarly, the historical daily solar radiation measured at the Manteca CIMIS Station averaged 436.79 Langleys over the three year monitoring period. 5.4 RELATIVE HUMIDITY Figure 4 illustrates the pattern of relative humidity observed at the Forward Sanitary Landfill Stage 1 A final cover area over the monitoring period. As shown therein, relative humidity was ' generally higher from late fall through winter (December—March). During the three year monitoring period, the average relative humidity at the FSL was about 62.88%. This compares ' well with the historical average relative humidity of that measured at the Manteca CIMIS station over the last 3 years. Between 1988 and 2006 historical average humidity was 69.1% at the Manteca station. 4 GeoLogic Associates