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DBCP is a nematocide and soil fumigant for vegetables and grapes. It is known to cause male reproductive effects and is classified as a probable human carcinogen. Most domestic use of DBCP was discontinued in 1977 through 1979. The US EPA set the MCL at 0.2 parts per billion (ppb, equivalent to ug/L) because it believes that given present technology and resources, this is the lowest level to which water systems can reasonably be required to remove this contaminant should it occur in drinking water. The Maximum Contaminant Level Goal (MCLG) for DBCP is zero. Soil Profile and Geologic Information The Site is depicted on the Geologic Map of the San Francisco-San Jose Quadrangle, California (Wagner, et. al, 1991). The Site is depicted within a map unit of the Modesto formation (Plate 11). The surface and near surface soils located at the Site are reported by the USDA Web Soil Survey to be composed of Delhi loamy sand and Veritas fine sandy loam (Plate 12) (USDA, 2019). The table below presents some selected properties of this soil: Table 1. Selected Properties of On-Site Soils (USDA, 1992) Soil Name Depth Unified Soil Salinity Soil Perme- Septic tank and Map (in) Class Reaction ability absorption Symbol Classification mmhos/cm pH (in/hr) fields Delhi loamy 0-16 Loamy sand; SM <2 6.1-7.8 6.0-20 Severe: sand, 0-2% 16-26 Loamy sand, loamy fine <2 6.1-7.8 6.0-20 poor filter slopes, 142 sand; SM 26-60 Sand, loamy sand, fine <2 6.1-7.8 6.0-20 sand; SP-SM, SM Veritas fine 0-15 Fine sandy loam; SM, <4 7.4-8.4 2.0-6.0 Moderate: sandy loam, SC-SM flooding, 0-2% slopes, 15-54 Sandy loam, fine sandy <4 7.4-8.4 2.0-6.0 cemented 266 loam; SM, SC-SM pan 54-70 Cemented -- -- -- Note: The table descriptions do not necessarily reflect site-specific soil properties. See description of the map unit for composition and behavior characteristics of the map unit. Soil Borings On November 4, 2019, Live Oak excavated a shallow soil boring near the proposed septic disposal area of the Site for the purpose of conducting a percolation test. The boring was four inches in diameter, 3.50 feet deep, and was excavated by hand auger (Table 2). The location of the boring is indicated on Plate 13. The soil in the boring was similar to that described by the Soil Survey but with more clay content. Fine sand with silt was encountered to a depth of 15 inches, followed by fine sand with clay to the full depth of the hole. The soil log is presented on Plate 14. LOGE 1945 Page 5