ARCHIVED REPORTS XR0011751 - Laserfiche WebLink

Home Browse Search

•+ Work Plan for Refined Plume Definition and Management of bating Product-7500 W 11th A, Tracy, CA. Page i -R Table of Contents PROFESSIONAL CERTIFICATION AND LIMITATIONS..................................................v �.. 1.0 INTRODUCTION...........................................................................................................................1 1.1 Site Location...............................................................................................................................1 1.2 Site Codes...................................................................................................................................1 .r 2.0 BACKGROUND......................................................................................................................... ..2 2.1 Ownership History of Site and Fueling Station..........................................................................2 2.2 Removal of Underground Fuel Storage Tanks...........................................................................2 2.3 Completed Phases of Soil Remediation and Floating Product Removal....................................2 2.4 Interim Measures for Removal of LNAPL from Area around MW-7....................... 3.0 GEOLOGY AND HYDROGEOLOGY..........................................................................................4 4.0 Site Characterization and Groundwater-quality Monitoring...........................................................6 4.1 Initial Site Characterization ....6 .................................................................................................... 4.2 Initial Quarterly Groundwater-quality Monitoring Program......................................................7 4.3 Extended Site Characterization .......................................•-•----....................................................8 4.4 Extended Quarterly Groundwater-quality Monitoring Program................................................8 4.5 Annual, Semi-annual and Quarterly Groundwater-quality Monitoring Program.......................9 4.6 Potable Water Supply Wells.......................................................................................................9 4.7 Summary of Completed Characterization and Monitoring Programs......................................10 5.0 Down-gradient Migration of Floating Product..............................................................................12 5.1 Initial Proposals for Removal of Floating Product...................................................................12 5.2 Estimates of Thickness and Volume of LNAPL in Subsurface...............................................13 5.2.1 Thickness of Floating Product..........................................................................................14 5.2.2 Recoverable Floating Product ...14 5.2.3 Area of Subsurface Affected by Floating Product...........................................................15 5.2.4 Volume Estimate for Engineering Design Purposes ....17 .................................................... 5.2.4.1 Total Volume..................................................................................... .....17 5.2.4.2 Recoverable Volume.........................................................................................•---...17 6.0 PROPOSED GROUNDWATER-QUALITY MONITORING IN DOMESTIC WELLS............19 6.1 Schedule ...................................................................................................................................20 6.2 Cost Estimate........................................................•-•-------•.........................................................21 ••� 7.0 ADDITIONAL MONITORING WELLS TO REFINE PLUME DEFINITION..........................22 7.1 Proposed Wells.........................................................................................................................22 7.2 Well Drilling and Soil Sampling..............................................................................................23 7.3 Disposal of Drill Cuttings.........................................................................................................24 7.4 Well Design....................................................................................... .....25 7.5 Well Development....................................................................................................................25 W 7.6 Survey of Well-head Locations and Elevations........................................................................25 7.7 Groundwater-quality Monitoring ........................................................... .....25 ............................. 7.7.1 Determination of Groundwater Elevations.......................................................................25 7.7.2 Well Purging....................................................................................................................26 '4 7.7.3 Groundwater Sampling Procedure ........26 ........................................................................... 7.7.4 Groundwater Sample Analyses........................................................................................26 7.7.5 Disposal of Purge Water...................................................................................................27 7.8 Field Modification......................................................................... .... -----.........27 7.9 Schedule ...................................................................................................................................27 7.10 Cost Estimate..................................................................................... ...28 ................................... sic