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Soil Suitability / Nitrate Loading Study Cherokee Memorial Park Vineyard Chapel Addition Ŷ Lodi, California March 5, 2021 Ŷ Terracon Project No. NA207102 Responsive Ŷ Resourceful Ŷ Reliable 21 3.0 CONCLUSIONS AND RECOMMENDATIONS In 2015, Neil O. Anderson & Associates, a Terracon Company, prepared prior SSS, NLS and ESS studies for the Vineyard Chapel project. Based on the results of NOA/Terracon’s 2014 field work, site soils consist primarily of silty sand and percolation test results (15.63 and 20.83 minutes per inch), indicate the soils within the proposed sewage disposal area appear suitable for a standard septic system. Two groundwater samples were collected from the domestic well. Nitrate as N was reported at 1.4 mg/L below the MCL of 10 mg/L-N. DBCP was reported at 0.12 μg/L in groundwater sample GW-2, below the MCL of 0.2 μg/L. The site is currently developed with seven septic systems and is proposed to be developed with an eighth septic system associated with the Vineyard Chapel addition. Based on the nitrate loading balance, nitrate levels for the existing land use (Septic Systems #1 to #7) is 3.9 mg/L-N, below the MCL of 10.0 mg/L-N. The proposed Vineyard Chapel addition (Septic System #8) is anticipated to increase nitrate levels for the site to 5.0 mg/L-N, which is also below the MCL. Based on the nitrate loading results, mitigation measures appear unwarranted. In summary, the parcel appears suitable for the proposed development. The septic system design should accommodate peak flows and follow the San Joaquin County OWTS standards where applicable. Per the client’s request, Terracon is preparing a separate septic system design report for the project. 4.0 LIMITATIONS As indicated, our study takes into account the subject property only with the sewage load applied over the property site area. The study does not take into account surrounding properties and/or lands. The method utilized for the nitrate loading analysis is based on a simple mass balance formula, discussed in a published article by Hantzsche and Finnemore (1992), which provides a convenient and simplified method to estimate long-term groundwater nitrate impacts on an area- wide basis. A more detailed analysis was not requested nor intended. Our professional services were performed, our findings obtained, and our conclusions proposed in accordance with generally accepted engineering principles and practices. This warranty is in lieu of all other warranties either expressed or implied. Test findings and statements of professional opinion do not constitute a guarantee or warranty, expressed or implied.