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concentrations of 5.5 mg/L-N or more (Hull, 1984). The US EPA has set the Maximum Contaminant Level (MCL) for nitrate at 10 mg/L-N. Although nitrate is a naturally -occurring compound necessary for plant growth, it can cause health problems when present at high levels in drinking water. The most common health effect of nitrates in water is methemoglobinemia, or blue baby syndrome, which results in reduced oxygen supply to vital tissues. Pregnant women and certain others can also develop methemoglobinemia. Symptoms include a bluish color of the skin, as well as headache, dizziness, weakness, and difficulty breathing. Ingestion of high levels of nitrates over time can also lead to gastric problems. 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. On -Site Wells No wells are located on the Site. Water Sample Because no wells are located on the Site, no water sample was collected as part of this investigation. Soil Profile and Geoloaic 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 9). The surface and near surface soils located at the Site are reported by the USDA Web Soil Survey to be composed of Hollenbeck silty clay (Plate 10) (USDA, 2022). The table below presents some selected properties of this soil: LOGE 2208 Page 4