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1900s, it is estimated that under "natural" conditions, ground water contains nitrate at concentrations no more then about 3 mg/L-N. Nitrate may be increasing in areas with 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 p,g/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. The well water should not be consumed until it can be brought to below the MCL for DBCP. According to David Wentrup, Food Safety Manager at Delta Packing, the facility is currently working on a plan to mitigate DBCP through the use of an ozone system (correspondence, March 11, 2021). Additionally, Mike Harnack of Roland Construction indicated that Delta Packing currently supplies bottled water for worker consumption at watering stations (correspondence, June 19, 2021). Soil Profile and Geologic Information The Site is depicted on the Preliminary geologic map of Cenozoic deposits of the Be/Iota quadrangle, California (Marchand and Bartow, 1979) within a map unit of the Modesto formation upper member (Plate 9). This map unit is defined as "arkosic alluvium forming Mokelumne River terraces and alluvial fan; chiefly sand with minor gravel and silt; probably glacial outwash." The surface and near surface soils located at the Site are reported by the USDA Web Soil Survey to be composed of Tokay fine sandy loam (Plate 10) (USDA, 2020). The table below presents some selected properties of this soil: LOGE 20-33 Page 5