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�./ `rte to a depth of eighty-five feet(see a recap attached). On May 2 and 3, 2000 the soil borings for both MW#5 and MW#6 were made as described in the Work Plan of 3/17/2000.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. 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 in the report issued for that work. 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 RAV 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, (MW-8S,MW-8D, MW-7,MW-9) to be placed on the project site or the adjacent property. These monitoring wells were completed on April 11, 2001. In January of 2002 the owners of this property removed the apartment house structure on the east side of the property. At the time of this report that portion of the property is clear without any structures or other improvements. Theory The major hydraulic properties of aquifers on a site can best be determined through a pump draw down test. The theory requires a steady state flow that produces a draw-down in the surrounding monitoring wells. Aquifers with high permeability require only short duration pumping,while low permeability aquifers require much longer pumping time to produce an acceptable draw-down curve. The draw-down curve is then used to determine extraction well pumping rates and the area of influence to determine extraction well spacing. Dupuit Theory of Unconfined Flow is proposed for determining both the"V factor and the projected"Q"for the first sand aquifer. The extraction well spacing will be determined by the radius of influence of the pump test well. In general the site has three sand aquifers. The first is located from twenty-five to thirty feet below the surface and is a fine sand. The second is located from forty to fifty-five feet below the surface. The third aquifer is located about seventy feet below the surface and is made up of sandy silts and fine sand. This aquifer is only about five to ten feet thick. Drill logs of MW-6 and push logs of CPT-1 and CPT-2 were used as foundation data for aquifer determination. The highest levels of TPHg are found in the second aquifer. MW-1 has continually produced groundwater samples with TPHg ranging from 200,000 to 100,000 ppb. This well is screened from thirty-seven to fifty-seven feet below the surface. This well produces high flow rates.The estimated "k"factor for the second aquifer is one times ten to the minus one. 2