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Kennedy/Jenks Consultants <br /> 1 remainder of the study. In the first year of study, a mid-summer sampling event to 2-feet <br /> depth will be conducted to better assess growing season trends. Analytes to be evaluated <br /> include percent moisture, total nitrogen, ammonia-N, NO3-N and NO2-N, salts (calcium, <br /> magnesium, sodium, potassium, chloride, sulfate, and bicarbonate), and EC. An SOG for <br /> shallow soil sampling is included in Appendix D. <br /> Soil samples at 60 inches will be collected to determine salt and nitrogen movement below <br /> the root zone up to five times per year. A sample will also be collected at 60 inches depth <br /> when the deepest soil moisture readings are increasing and near field capacity. <br /> • Soil Moisture Monitoring. Soil moisture monitoring will be used to evaluate whether the <br /> irrigation schedule employed is suitable for optimizing crop growth/removal of nitrogen and <br /> salts and soil assimilation of salts. Continuous soil moisture monitoring at approximately <br /> 1-foot depth increments to 5 feet will be conducted in the test plots for comparison of soil <br /> moisture beneath various crops. The continuous soil moisture data will be transmitted to a <br /> centralized computer. Woodbridge will use Sentek TOSCAN soil moisture monitoring probes <br /> for the continuous soil moisture monitoring. <br /> Additional soil moisture monitoring at 1 foot intervals will be done by hand.This activity will <br /> be conducted throughout the test plots to assess spatial variability in soil moisture due to <br /> variation in soil properties, crop factors, and irrigation. Monitoring depths may be adjusted to <br /> match those established in the soil sampling task above. The weekly soil moisture data will <br /> be collected in the field with a data logger and later downloaded to a computer. Woodbridge <br /> will use the Diviner 2000 for the weekly soil moisture monitoring. <br /> • Soil Water Flux Calculations. An estimate of soil water flux will be made approximately <br /> weekly for each TriSCAN soil moisture probe. Rainfall and irrigation amounts will be totaled <br /> for each soil water flux measurement period. Two rain gauges will be installed at the site to <br /> directly measure rainfall. <br /> Evapotranspiration (ET) for the plot will be based on CIMIS reference evapotranspiration for <br /> the Lodi West station. Soil water flux at 5 feet will be calculated as change in soil moisture <br /> storage minus irrigation minus rain plus evapotranspiration. If this quantity is negative in <br /> sign, this indicates percolation. A positive sign would indicate upward flow. <br /> Flux = A soil moisture— irrigation — rain + ET <br /> • Deep Vadose Zone Soil Sampling. An annual assessment of soil conditions below 5 feet <br /> will be made using one soil boring per test plot. This assessment will allow an evaluation of <br /> subsurface concentrations of salts and nitrogen. This sampling event will take place in <br /> conjunction with other soil sampling. If distinct changes in conditions are noted, Woodbridge <br /> may elect to continue this sampling program. An SOG for deep soil sampling is included in <br /> Appendix E. <br /> 3.3 Data Evaluation <br /> Measured data for the study will be collected at varying frequencies. For this reason, evaluation <br /> efforts will be performed at different time increments. Soil moisture and percolation analysis will <br /> Crop Uptake and Assimilative Capacity Work Plan, Page 6 <br /> Woodbridge Winery, Acampo, California <br /> i , <br />