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SSS§ 6.3. After drilling, the sidewalls of the two borings were scored with a pry-bar to open potentially smeared soil surfaces. Two inches of pea gravel was placed at the bottom and a three- inch perforated PVC pipe was inserted in each test boring. After these procedures, the borings were pre-saturated with 12 inches of water approximately 24 hrs prior to the start of testing. SSS§ 6.4, 6.5. On June 26, 2020, percolation testing commenced at 0700 hrs. No standing water was observed in either boring after the 24-hr soak period. Consequently, EHD Perc Test Procedure #2 was conducted. Testing was done over a four-hour period to induce maximum soil saturation. A summary of the perc test results with corresponding application rates in gallons of effluent accepted per square foot of soil per day are illustrated below: TABLE 2 PERCOLATION TEST RESULTS WITH CORRESPONDING APPLICATION RATES IN GALLONS/FT'/DAY LFW40 PERC TEST 14.7 min/inch / 0.729 gallons/ft'/day Leachfield West 40" Deep Perc Test LFE40 PERC TEST 19.2 min/inch / 0.671 gallons/ftZ/day Leachfield East 40"Deep Perc Test Application Rates adapted from Waste Quality Control for Siting,Design,Operation and Maintenance of On-site Wastewater Zreatment Systems,based on the Perc Rate. D. GROUNDWATER INFORMATION NLS§2.1, SSS§ 4.1. Groundwater depths and elevations throughout San Joaquin County are illustrated on maps published by the County Flood Control and Water Conservation District. The 1999 Lines of Equal Depth Map, which is regarded as one of the highest depths to groundwater on record, indicates the depth to water at approximately 25 ft. The Fall 2016 Lines of Equal Depth illustrate approximately 53 ft depth to groundwater revealing a significant drop in water table elevation due to excessive pumping and limited recharge during serious drought periods. From the Lines of Equal Elevation Maps, groundwater directional flow is in a north-northwesterly direction. NLS§2.2,3.1, SSS§ 2.1, 4.2. Properties to the north, south, east and west are currently agricultural production and rural residential. Considering this area was farmed for decades, there is a significant potential for nitrate contamination of the underlying groundwater from nitrogen fertilizer applications and residual organic matter decomposition. NLS§2.3, SSS§ 4.3, 4.4, 4.5, 4.6. There are two wells on the property. The main drinking water/process water well that serves the winery was sampled for this Study and is located at the north end of the facility. A small, newer domestic is also found at the north end of the property. A new public well to serve the entire winery is currently undergoing the approval process through EHD and the State of California. Test results in Appendix F illustrate the nitrate as nitrogen concentration to be 24.7 mg/L, or 2.5x over the Maximum Contaminant Level (MCL). Page -4- Chesney Consulting