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LUCCA WINERY SOIL SUITABILITY & NITRATE LOADING STUDY MAY 2013 NLS§ 3.3 Table 1 below summarizes the subsurface soil characteristics encountered from the two sample depths below grade: Table 1 — Soil Profile Characteristics and Analytical Test Results Soil Profile Characteristics and Analytical Test Results Sample Depth Soil Nitrogen Content NO3-N Cation Exchange Capacity, Soil Below Ground Surface ft (ppm) CEC (meq/100g) pH Classification' 3.0 4.0 5.7 5.7 Loamy Sand 7.0 1.0 5.8 6.6 1 Loamy Sand Note 1. Soil Classification per the NRCS Map Unit Description of Delhi Loamy Sand C. Percolation Test Results SSS§ 6.2. To assess the permeability of the on-site soils, two percolation test borings were completed in the proposed leachfield location as depicted in the Site Plan found in Appendix B. The "EHD Official' perc test depth at 36 inches below existing grade gives a comparatively detailed observation of subsurface permeability from approximately 30 to 36 inches in depth. The second depth at 84 inches below existing grade provided a detailed observation of subsurface conditions in regards to the effects of deep percolation of water and denitrification due to the porous soils. As noted in Table 2 below, both test borings possess rapid permeability. SSS§ 6.3. On December 13, 2013, the perc test borings were drilled in the referenced locations. The sidewalls of the borings were scored with a pry-bar to open potentially smeared sidewalls. Two inches of fine gravel was placed at the bottom and four-inch perforated PVC pipe was inserted in the two borings. The test borings were pre- saturated with 12 inches of water at 0900 hrs, 24 hrs before the start of testing. SSS§ 6.4, 6.5. On December 14, 2013, percolation testing commenced. No standing water was observed after the 24-hr soak period in either test boring. Consequently, EHD Perc Test Procedure #2 was conducted initially in which testing was done over a four-hour period to induce maximum soil saturation. When the test was commenced, the percolation rate did not leave standing water at the 30 minute mark. Upon the initiation of the test, EHD sanitarian Ted Tasiopolous, REHS reviewed the percolation rate and authorized EHD Perc Test Procedure #3, in which the test was performed over a one-hour period. The test results indicate a perc rate at 1.9 minutes per inch (min/in) for the 3 foot depth test boring and 6.7 (min/in) for the 7 foot depth test boring. The percolation test rate form can be found in Appendix E, A summary of the perc test results with corresponding application rates in gallons of effluent accepted per square foot of soil, per day are found in Table 2: Page 14