Laserfiche WebLink
;rY Q iy <br /> plan was the installation of three CPTs.To date CPT#1,CPT92 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 (see a recap attached). <br /> 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 /> CPT#3 was installed on June 13,2000 in the Caltrans right of way. This CPT is northeast of the site, <br /> and the data gathered is in the report issued for that work. <br /> All monitoring wells have been sampled quarterly, and a recap of the findings is attached. <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 /> RIW 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. In April of 2002 the author submitted a work plan for the <br /> installation of an extraction well with pump test to determine the viability of a pump and treat <br /> remediation system. <br /> On August 9 & 10, 2002 the extraction well installed for the pump test was completed and <br /> developed. <br /> REPORT OF FINDINGS FOR THE THIRD QUARTER 2002 MONITORING EVENT <br /> Procedure <br /> On September 17,2002,Del Tech Geotechnical Support Services extracted water samples from all <br /> of the monitoring wells on the above stated property. The work was supervised by Foothill <br /> Engineering. Some of the monitoring wells were in need of maintenance with missing locks and low <br /> grout cal umn. All samples were extracted using the tube with check valve pump system.Purge rates <br /> were+/-.5 g.p.m, and the physical properties of the groundwater can be found in the Del-Tech Field <br /> 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. All water sample analysis and groundwater <br /> elevations are summarized in the attached tabular recap sheet (see attached recap sheets). Copies <br /> of the original Laboratory data sheets from this sampling event are also attached and are a part of <br /> 2 <br />