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D R A F T January 4, 2012 In the onsite fields surrounding the ponds, the distance to groundwater from the land surface is between 2 and 14 feet, and this short distance to groundwater may be a critical factor in assessing whether the field application of wastewater causes adverse water quality impacts. The distance to groundwater is also a concern in those portions of the fields initially receiving furrow or flood-irrigation of the wastewater mix. Each initial application area at the head end of a field has a considerably longer time period for the downward movement of wastewater to occur than at the other end of the field. An additional concern related to the land application of the biosolids wastewater mixture is that, except for nitrogen compounds and potassium, the majority of the TDS is non-nutritive. Because plants do not have a significant uptake of these salts, they tend to move unchanged down to groundwater. b. Industrial Wastewater CALSPA contends that the industrial waste stream does not qualify for a Title 27 exemption because the cannery wastewater exceeds water quality objectives for nitrogen and EC. Further, the other waste generators are capable of producing wastewater containing metals and other hazardous constituents. There is insufficient evidence in the record to assess this contention. The EC and TDS values for the industrial waste stream generated during the canning season often do exceed water quality objectives. The food processing wastewater also contributes significant nitrogen loading. The salts in this waste stream are of particular concern, as discussed above, because the majority of the salts are expected to move directly to groundwater. However, the waste stream is mixed with other liquid wastes before it is applied to the agricultural fields. Therefore, the focus must be on the wastewater mixture that is applied to the fields, and our conclusions on the potential water quality impacts of the land application of the biosolids wastewater mixture apply as well here. There are limited data in the record on the quality of the other industrial waste streams discharged by the City. In 2000, the Central Valley Water Board required the City to investigate whether three metal finishers were discharging hazardous waste to the industrial influent line. Based on data collected between 1997 and 1999, the Central Valley Water Board determined that the constituents in all samples did not exceed the hazardous waste levels specified in the Title 22 regulations; however, the investigation was limited to metals and fluoride.46 The record does not contain data for all users nor for all pollutants, such as organic 46 See letter from Del Kerlin,Assistant Wastewater Treatment Superintendent, City of Lodi, to Robert Fagerness, Central Valley Water Board (Feb. 8,2001),AR,vol. 5, item 183. 18.