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SCSA—University Park Site Background Page 3' i groundwater sample collected from monitor well MW-2. BTEX, TPH-G, total petroleum hydrocarbons quantified as kerosene (TPH-K), MTBE, and 1,2-DCA were detected in the groundwater sample collected from monitor well MW-3 at concentrations generally consistent with historical results. The groundwater gradient direction (northeast) was similar to the gradient direction measured during the soil and groundwater investigation activities conducted on December 18, 2001 (slightly north of east). Condor prepared a Problem Assessment Work Plan (PAWP) dated January 23, 2003, to describe additional groundwater investigation at the Site. The PAWP was prepared at the request of Mr. David {. Rosso for the Trustees of the California State University in response to a letter dated April 26, 2002 from Ms. Setliff of the SJCEHD. The purpose of the proposed work is to further investigate the lateral and L vertical extent of petroleum hydrocarbon contamination in groundwater at the Site. As requested by the SJCEHD, the PAWP also included a remedial feasibility evaluation that compared and discussed remedial techniques for Site remediation. Condor prepared a Soil and Groundwater Remediation Work Plan, dated March 3, 2003, at the request of Mr. David Rosso for the Trustees of the California State University. The scope of work described'in this work plan includes(1) groundwater dewatering with dewatering wells, groundwater treatment, and proper disposal of treated groundwater; (2) soil over-excavation, including transport and disposal of contaminated soil; and(3)in-situ groundwater remediation utilizing ozone sparging technology. Nuel Henderson of the SJCEHD approved the PAWP in'a letter dated March 27, 2003. Mr. Henderson also approved the soil over-excavation portion of the Soil and Groundwater Remediation Work Plan as an interim remedial measure. However, Mr. Henderson also indicated that ozone sparging would'not be considered by the SJCEHD until Site characterization was complete. On March 13, 2003, a Condor representative was on Site to measure water Ievels and collect water samples from the three monitor wells. A slight petroleum odor was noted in the field inspection samples collected from MW-2 and MW-3. The laboratory analytical results .indicated that -no petroleum ' hydrocarbon constituents were detected in the groundwater sample collected from monitor well MW-1. BTEX, TPH-G, total petroleum hydrocarbons quantified as diesel and motor oil (TPH-D, MO) and 1,2- DCA were detected in the groundwater sample collected from monitor well MW-2. BTEX, TPH-G, total �. petroleum hydrocarbons quantified as diesel (TPH-D), MTBE, and 1,2-DCA were detected in the t groundwater sample collected from monitor well MW-3 at concentrations generally consistent with ' historical results. The groundwater gradient direction (southeast) was generally consistent with historical groundwater gradients. On April 14 through 17, 2003, Condor conducted an additional groundwater investigation at the Site using direct push boring methods. Condor supervised the completion of five deep CPT boring pairs and one shallow hydropunch boring. Findings of the work were described in the Additional Groundwater Investigation Report, dated August 19, 2003, prepared by Condor. Based on the laboratory analytical results of the groundwater samples, the extent of groundwater contamination is adequately investigated up-gradient and cross-gradient at the Site. In addition, all petroleum hydrocarbon constituents other than TPH-D and 1,2-DCA (including BTEX and MTBE) are very limited in extent, laterally and vertically, in the down-gradient direction. Condor recommended the installation of additional monitor wells at the Site to investigate and monitor deep groundwater in the source area and shallow and deep groundwater in the down-gradient portion of the Site. Condor also reaffirmed its recommendation for soil over-excavation and ozone sparging in the source area. However, Condor recommended that any further work not be conducted at the Site until the Site disposition, relative to soil over-excavation and the demolition of the Site structures, was decided. G -