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to correct the over screen conditions of the existing monitoring wells. Also, included in this work <br /> plan was the installation of three CPTs.To date CPT#1,CPT#2 and CPT#3 have been installed.Soil <br /> and groundwater samples extracted during the installation of CPTs indicate gasoline contamination <br /> to a depth of eighty-five feet. <br /> On May 2 and 3, 2004 the soil borings for both MW#5 and MW#6 were made as described in the <br /> work plan of 311712000.Monitoring wells were installed in both of these soil bores. The work plan <br /> of 3/1712000 also included a soil bore and monitoring well(MW#4)to be installed in the sidewalk <br /> on the north side of Lafayette Street. This soil bore was not completed as planned. An unknown <br /> underground storage tank was encountered in the direct path of the soil bore. As a result of this <br /> encounter, the soil bore was abandoned and the local agencies were notified. <br /> A work plan to expand the horizontal definition of the contamination plume was approved in <br /> December of 2000.This work plan called for the installation of three new CPT's within the Caltrans <br /> R/W to the north of the project site. These CPT's were completed on March 8, 2001 and soil and <br /> water samples were extracted to a depth of 125 feet. Also, included in the work plan of December <br /> 2000 was the installation and testing of four new monitoring wells,MW-8S,MW-81),MW-7,MW- <br /> 9, to be placed on the project site or the adjacent property. These monitoring wells were completed <br /> on April 11, 2001. <br /> In January of 2002 the owners of this property removed the apartment house structure on the east <br /> side of the property. At the time of this report that portion of the property is clear without any <br /> structures or other improvements. <br /> On August 9 & 10, 2002 the extraction well installed for the pump test was completed and <br /> developed. In December of 2002,work crews under the control of others,removed the buildings on <br /> the lot directly East of the site. This lot is not owned by the Olivarez's. Monitoring wells MW-8S <br /> and MW-81)were damaged and the caps and covers were removed along with the upper portion of <br /> the casing by the crews removing the buildings. These monitoring wells were repaired in March of <br /> 2003. <br /> i <br /> j Funds were made available for extraction well pump test. The pump test was performed on June 25, <br /> 2004. The pump test successfully demonstrated that the extraction well has influence with all areas <br /> that are contaminated. <br /> 1 <br /> Recommendations <br /> Extraction Well EW-I was installed with a 6" casing and screened on an interval from 45' to 60' <br /> below ground surface. EW-1 targets the sand layer from 45'to 80'and is centered in the eye of the <br /> plume. This sand layer represents 90% of the mass of contamination. The pump test of EW-I <br /> showed that it had influence with all monitoring wells.Foothill Engineering recommends that EW-I <br /> used in the pump test also be used for the pump and treatment of ground water. As with all <br /> remediation plans the effectiveness of the plan will be evaluated with each quarterly monitoring and <br /> revisions will be proposed as needed. <br />