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On March 15, 2021, a mini-excavator was used to excavate down to 9 ft in the proposed effluent I disposal area to explore for hardpan strata. A cemented silts hardpan stratum was encountered at 6 ft b.g.s. that extended for an approximate thickness of 6". Soil samples were retrieved from 3 ft; from the hardpan stratum at 6 ft; and from 9 ft to conduct chemistry and particle size analysis on these three soil samples. The complete soil analysis report can be found in Appendix C. The primary constituents of the retrieved soil samples are illustrated below in Table 1. TABLE 1 SOIL PROFILE CHARACTERISTICS AND ANALYTICAL TEST RESULTS SAMPLE DEPTHS SAND,SILT AND SOIL LAB SAMPLE ID CLAY CLASSIFICATION pH AND PERCENTAGES HYDRAULIC SOIL CATION EXCHANGE CAPACITY GROUP Three Ft Depth 78%, 16°/g 6% Loamy Sand 8.4 10.4 meq/100g 3FT Group A Six Ft Depth/Hardpan Stratum 50%,40%, 10% Loam 8.8 12.8 meq/1008 6FTHP Group C Nine Ft Depth 58%,34%,8% Sandy Loam 8.5 10.9 meq/1008 9FT I I Group B In comparing the saturated hydraulic conductivity(K.) of the soil samples referenced in Table 1 as estimated through the particle size analyses,the following data can be concluded: The classification of soils in the United States and the world is highly complex; however soils in the U.S. can be generally placed into four Hydrologic Soil Groups (HSG) for infiltration purposes: A, B, C and D and three dual classes A/D, B/D and C/D. Soils from the 3 ft depth can be classified in Group A in which K.,is very high. These soils have less than 10% clay and can have more than 90% sand. The K.,exceeds 5.67 inches per hour (iph). The soil under the hardpan stratum can be classified as Group B. These soils typically have between 10%and 20%clay and 50%to 90% sand,which corresponds with the particle size analysis. The K.,ranges from a low of 1.42 iph to 5.67 iph for this soil type. The hardpan stratum soil can be classified as Group C, and is 50%composed of the fine soil fractions (40% silt and 10%clay). K,t ranges between 0.14 iph and 1.42 iph. Using the median value between this range, 0.78 iph is derived. This is equivalent to 77 minutes/inch(mpi). Since the hardpan stratum is approximately 6 inches in depth, it will take approximately 462 minutes (7.7 hrs) for the effluent to percolate through this cemented silts hardpan stratum. i Page-2- Chesney Consulting