SITE INFORMATION AND CORRESPONDENCE

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` WASTE DISCHARGE REQUIRE•S ORDER NO. • 9 MUSCO FAMILY OLIVE COMPANY AND THE STUDLEY COMPANY WASTEWATER TREATMENT FACILITY SAN JOAQUIN COUNTY NA denotes Not Available. a Denotes value shown is an average of available data. b Denotes value calculated from all data available in RWD(not from average values calculated from each well as shown in this table). 42. Thirteen groundwater monitoring wells were installed in March and April 2002; one existing well was redeveloped. The locations of the monitoring wells are shown on Attachment B. The wells were sampled in April (with the exception of Well MW-9 because it did not have enough water to collect a sample). Shallow and deep zones of groundwater were identified in the investigation. A summary of the groundwater quality data is presented below: Well TOC Elev. Screen Depth EC TDS Cl Na NO3 as N ft. msl ft. b s mhos/cm m /I (mgV m L (,mg/L) MW-1(S) 443.13 30-45 1,300 690 67 240 11 MW-2(S) 403.53 149.5-164 15,000 9,800 130 2,400 1.2 W-2 (1985)(S) 261.93 20-50 1,200 690 33 240 3.2 MW-3(S) 308.75 9.5-19.5 5,000 2,700 880 770 0.91 MW-5(S) 292.05 25-45 3,900 2,200 670 600 ND MW-6(S) 329.39 40-55 4,800 2,600 830 780 16 MW-10(S) 259.68 11.5-21.5 4,800 2,700 1,300 820 16 MW-II(S) 273.68 35-40 3,400 2,000 690 620 9.7 MW-13(S) 372.00 10-25 5,700 3,000 1,400 790 37 MW-4(D) 333.72 234.5-249.5 2,000 1,200 92 330 3.7 MW-7(D) 266.00 154.5-169.5 3,700 2,400 540 550 3.3 MW-8(D) 288.56 208.5-228.5 2,100 1,300 130 280 5.2 MW-9(D) 291.83 126.5-141.5 Well was dry MW-12(D) 269.25 85-100 3,300 2,100 580 500 14 EC denotes electrical conductivity. TDS denotes total dissolved solids. Cl denotes chloride. Na denotes sodium. NO,as N denotes nitrate as nitrogen. ND denotes not detected. Well MW-2(1985)is an existing well installed in 1985. Depth zone indicated in well name(S)indicates shallow,(D)indicates deep. 43. The depth to groundwater at the Discharger's facility is dependant on the well location. Monitoring wells with shallow groundwater are in low land areas or in close proximity to the surface drainage course. Wells with deep groundwater are typically in higher topographic elevation areas further away from the surface water drainage. Depth to groundwater varied from 14 to 175 feet below ground surface. Land surface elevations vary from 259 to 443 feet above mean sea level. 44. Groundwater flow directions generally mimic the topography. Overall the flow direction is to the northeast, however, topographic variations can significantly change the local flow direction. 45. While the Discharger has shown that local groundwater is of generally poor quality,the on site monitoring wells show that the Discharger's activities may have impacted the underlying groundwater. the Groundwater Monitoring Well Installation Report identified the chemistry of the groundwater in the shallow and deep zones was reported to be distinctly different,with shallow zones tending to have higher concentrations of sodium, chloride, and total dissolved solids. v:u.._.w�x..uwmww.roe.�wowu.e..