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The quantity of water required to be leached through the root zone to change thesoil salinity <br />from 3.7to 2.9 dS/m was calculated using standard agricultural leaching equations(Equation 1) <br />(Hanson et al. 1999). The calculations were conducted assuming a coarse textured soil, soil EC <br />data collected at the site,intermittent sprinkler irrigationand a rooting depth of approximately <br />six feet. <br />Equation 1 <br />Where: <br />Dw = depth of water infiltrated (feet) <br />Ds = depth of soil to be reclaimed (feet) <br />k = 0.1(sprinkling) <br />ECe = final soil salinity desired <br />ECeo = initial soil salinity <br />Based on calculations is estimated that approximately 10.0 inches of water would need to be <br />leached past the rooting zone. Leached water is water percolated through the root zone in excess <br />of crop water demands. In general over the course of five years the leached water will equateto <br />the application of approximately 6% excess water beyond crop requirements percolating below <br />the root zone.Agronomic leaching has been conducted in California for years with annual <br />agronomic leaching exceeding 10% with no harm to alfalfa productivity. <br />This is a fairly low quantity of water especially when consideringthat the agronomic leaching <br />with sprinkler irrigation is planned duringthe first five years of reclamation on the Morgan <br />Property. Intermittent agronomic leaching withsprinkler irrigation isthe most efficient method <br />of agronomic leaching(Hanson et al., 1999). <br />The reclamation plan developed and outlined in PR07 includes management of soil salinityusing <br />agronomic leaching, if required.In general, agronomic leaching will be conducted using a <br />combination of CC ditch water and natural precipitationand at times of the year and at rates <br />which do not negatively affect crop growth and development. <br />References <br />Ayers, R.S., and D.W. Westcot. 1985. Water quality for agriculture.FAO Irrigation and <br />Drainage Paper 29 (Revision 1), Food andAgriculture Organization of the United Nations, <br />Rome, 174 p. <br />Food and Agricultural Organization of the United Nations (FAO). 2002. Annex 1, Crop salt <br />tolerance data InAgricultural Drainage Water Management in Arid and Semi-Arid Areas. Found <br />at; http://www.fao.org/DOCREP/005/Y4263E/y4263e0e.htm <br />12 <br />{00136879.1 } <br />