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f DER Bright Bright People. Right Solutio - seen in past results. Additional, it should be noted that the HELP model results do not depict seepage until January 2011, also similar to past results. 2.4 MODELING OF SEEPAGE THROUGH PRESCRIPTIVE CAP Performance of the Title 27 Prescriptive Cap was modeled using HELP and Test Pad precipitation data collected so far during the 2010/2011 water year. The Prescriptive Cap was setup in HELP using the following values: i Layer 1 (vegetative cover), 12 inches thick, sandy silt (HELP soil texture #7) ® Layer 2 (barrier layer), 12 inches thick, clay (HELP soil texture #16, hydraulic conductivity adjusted to 1x10-6 cm/sec) ® Layer 3 (foundation layer), 24 inches thick, sandy silt (HELP soil texture 7) The modeled results showed 1,118.15 cu ft seepage. Results of the HELP modeling are summarized in Table 1. The HELP modeling printout can be found in Appendix B. Chart 1 shows the rainfall vs. seepage volume with actual and modeled data. Performance of the ET Test Pad (using seepage out of the bottom of the cap) was compared directly to the modeled performance of the Title 27 Prescriptive Cap. 2.5 SOIL MOISTURE MONITORING Soil moisture sensors were installed with the ET Test Pad at the request of RWQCB staff; however, soil moisture is not a criterion for ET cover evaluation. This data presents monitoring data collected since fall 2006. 2.6 PREVIOUSRAIN E The ET Test Pad was fitted with soil moisture sensors set at depths of 1, 2 and 3 feet below the ground surface. Soil moistures in 2006/2007 were low, a reflection of the recently constructed ET Final Cover. The variability in the shallowest probe was greatest, as it was influenced most heavily by the cycles of wetting and drying caused 47717.11/ST011R193 Page 5 of 9 August 31, 2011 Copyright 2011 Kleinfelder