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On May 2 and 3, 2000 the soil borings for both MW45 and MW#6 were made as described in the . Work Plan of 3117/2000. Monitoring wells were installed in both of these soil bores. The Work Plan of 3/17/2000 also included a soil bore and monitoring well (MW#4)to be installed in the sidewalk on the north side of Lafayette Street. This soil bore was not completed as planned. An unknown underground storage tank was encountered in the direct path of the soil bore. As a result of this encounter,the soil bore was abandoned and the local agencies were notified. A recap of the results of sample analysis for MW#5 and MW46 are attached. CPT#3 was installed on June 13,2000 in the Caltrans right of way.This CPT is northeast of the site, and the data gathered is attached. All monitoring wells have been sampled quarterly, and a recap of the findings is attached. A Work Plan to expand the horizontal definition of the contamination plume was approved in December of 2000.This Work Plan called for the installation of three new CPT's within the Caltrans R/W to the north of the project site. These CPT's were completed on March 8, 2001• and soil and water samples were extracted to a depth of 125 feet. Also included in the Work Plan of December 2000 was the installation and testing of four new monitoring wells to be placed on the project site or the adjacent property. REPORT ON THE INSTALLATION OF CPT#4, CPT#5, AND CPT#6 Procedure During March 7 and 8, of 2001, Gregg Drilling of Martinez, California installed three new CPT's in the parking area under State Route 4 about 150' to 200' Northeast of the former UST site (See Gregg Drilling report and a site map attached). CPT#4 was installed about 150'Northeast of the site to a depth of 125'. Three soil samples and three groundwater samples were extracted as shown on the attached analysis recaps. CPT#5 was installed at a distance of 200'Northeast of the site to a depth of 90'.Three groundwater and soil samples were extracted from this CPT. The first try at installing this CPT was met with refusal at less than 20 feet of depth. Installation of CPT#6 met with refusal at a depth of 54'. Due to the refusal, only two soils and groundwater samples were extracted from this CPT. Findings From CPT Installation and Sample Analysis Cone penetration test data indicates a well-defined aquifer between 50 and 55 feet of depth. Groundwater and soil samples in this aquifer at CPT#6 indicate the presence of gasoline contamination. This CPT is located about 200'east of the former UST location on the south edge of the Caltrans Highway 4 R/W.The Groundwater sample from 54'of depth had TPHg of 31,300 ug/L. The soil sample from the same aquifer at CPT#6 had positive results for BTEX compounds and a non-detectable TPHg. •� First groundwater samples from all three CPTs installed under this Work Plan were not contaminated. 2