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On May 2 and 3, 2000 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 3/17/2000 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-8D,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-8D 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 welts were repair in March of <br /> • 2003. <br /> REPORT OF FINDINGS FOR THE FIRST QUARTER MONITORING EVENT <br /> Procedure <br /> On June 25,2003,Del Tech Geotechnical Support Services extracted water samples from all of the <br /> monitoring wells on the above stated property and extraction well EW-1. The work was supervised <br /> by Foothill Engineering. <br /> All samples were extracted using the tube with check valve pump system with exception of EW-1. <br /> Purge rates were +/- .5 g.p.m on monitoring wells and the physical properties of the groundwater <br /> can be found in the Del-Tech Field Report which is attached and part of this report. <br /> The replacement and original monitoring wells were sampled for analysis. The original monitoring <br /> wells (MW-1, MW-2, MW-3) were used to establish the groundwater elevation and hydraulic <br /> gradient. All samples were transported under chain of custody to Sherwood Labs of Hilmar, <br /> California for analysis by EPA method SW8020F. Samples were transported under chain of custody <br /> to Entech Analytical Labs for analysis by EPA Method 8260FA for oxygenates including 1,2-DCA <br /> and EDB. All water sample analysis and groundwater elevations are summarized in the attached <br /> tabular recap sheet. Copies of the original Laboratory data sheets from this sampling event are also <br /> attached and are a part of this report. <br /> • Findings <br /> The groundwater elevation at time of monitoring was within P of the last monitoring event. MW-1 <br /> continues to have the highest concentration of the monitoring wells with gasoline contamination <br /> 2 <br />