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v 2.7 in/yr 32 MR NIL CL--0.251+ (t I in/yr x 0.1 mg/L) ,. Nr = (2.7 in/yr+ 11 in/yr) Nr = 5 ppm as NO3-N E. COMPARISON BETWEEN AGRONOMIC INPUT IF PROPERTY.REMAINED IN AGRICULTURAL PRODUCTION VERSUS PROPOSED DEVELOPMENT OF THE PROJECT. As referenced above, the two proposed Parcels are currently planted in six-year-old almond trees. Consequently, comparison shall be made between nitrate impact from the fertilization of 4.5 acres of almond trees vs. nitrate impact from the proposed development of two SFRs on this same 4.5 acres. Calculated nitrate impact from the two SFRs was estimated to be 5 ppm NO3-N. Therefore, the question is: What concentration of nitrate from fertilizer and organic matter is not taken up by the almond tree root system and leaches past the root zone? There are a number of computer programs available to analyze this question, most notably NLEAP -Nitrate Leaching and Economic Analysis Package. However, nitrate-nitrogen'loading originating from the existing almond orchard will be based upon analytical test results and calculatedprojections 4 during the growing season. It is important to note that these test results were of course, obtained at the end of the growing season. The majority of nitrate-nitrogen leaching occurs during the growing season, especially in sandier soils. Although there will be some hindrance of the downward migration of nitrate from the hardpan stratum, this strata is intermittent according to Mr. Sephos who has farmed this area for several years. As noted, the soil structure becomes increasiay sandier with depth, thus acceleratin the downward movement of nitrate, particularly with flood irriatron. Nitrogen loading analysis starts at the beginning of the growing season in the springtime. Mr. Sephos applies a total of 200 units (200 lbs/ac) of ammonium nitrate over the course of the growing season, in four equally-timed applications of 50 units each(assume ammonium is taken up by the trees or converted to nitrate for uptake or leaching). According to the Western Fertilizer Handbook(Table 4-1), almond trees require 200 lbs of nitrogen per acre yieelld of 3000w.lbsI,so the„,xutroge aplzcations maw besomevvhat high forsiyea old trees. Nitrogen applications are water-run by flood irrigation. Unlike drip or micro-sprinkler irrigation where the irrigation water and nutrients are applied directly to the spatial orientation of the tree roots, flooirrigation allows a grcentnge of water and nutrients to by-passaree roots that do not extend out into the middle rows (rows between trees rows). This leaching percentage can be anywhere from 15%to 30%. Consequently, a higher concentration of nitrogen must be applied to counteract this leaching loss. As referenced in Section II B-1, chemical analysis was done to quantify NO3-N (and other constituent) concentrations at three soil horizon depths: 40 inch, 6 ft and 12 ft. As noted on the SOIL ANALYSIS REPORT, the concentrations of NO3-N are 4 ppm, 3 ppm and 3 ppm for each respective depth. Focus is placed on the NO3-N concentration of 3 ppm from 6 ft to 12 ft, since this is theoretically below the root zone. 9 VaderJ. Ag research