Laserfiche WebLink
' Atlantic Richfield Company 3 <br /> ARCO 6020 1711 Yosemite Avenue Manteca CA Apn] 12 2001 <br />' Groundwater Monitoring Well Development, Sampling and Surveying <br /> On February 15, 2001, the groundwater monitoring wells were developed by rigorously <br />' surging over the length of the screen interval and by purging approximately 15 to 3 <br /> casing volumes of water Purge volumes were less than standard development volumes <br />' because the monitoring wells went dry during development If turbidity is high during <br /> future sampling events, additional development will be conducted Following <br /> development, groundwater samples were collected from the newly installed groundwater <br />' monitoring wells Groundwater samples were analyzed for TPHg, BTEX, and MtBE by <br /> EPA Method 801518020, and fuel oxygenates (MtBE, DIPE, TAME, EtBE, TBA, EDB <br /> and 1,2-DCA) by EPA Method 8260 <br /> 1 EPA Method 8260 analysis of well MW-6 indicated MtBE and TAME at concentrations <br /> of 1,760 ppb and 4 79 ppb, respectively Other analyses did not detect the compounds <br />' tested for Groundwater analytical results are presented as Table 2 Field and laboratory <br /> procedures are presented as Attachment C Groundwater sampling parameters are <br /> included on the field sheets in Attachment E <br />' Tom Morrow Surveying, a California licensed surveyor, surveyed the groundwater wells <br /> relative to mean sea level Attachment F contains the surveyor's site plan showing the <br />' locations and elevations of the wells <br /> Groundwater Flow Direction <br />'ie Depth to groundwater in the wells ranged from 19 02 feet bgs to 20 92 feet bgs Based <br /> on monitoring data collected on February 15, 2001, groundwater flow was to the north <br />' with a gradient of 0 003 ft/ft (Figure 3) <br /> Well Survey <br />' Well logs for San Joaquin County are being electronically scanned for the California <br /> Department of Water Resources (DWR) and are currently unavailable for examination <br /> When the DWR well logs are available for review, SECOR will complete the 2000' <br />' radius well survey and submit it under separate cover <br /> Stockpiled Soil and Purge Water Disposal <br />' Approximately 6 tons of soils generated during the installation of the six monitoring <br /> wells were stockpiled onsite One composite sample (4 sleeves to 1 sample) was <br />' collected from the stockpiled soil and analyzed for TPHg, BTEX, MtBE, and total lead <br /> Soil was disposed of at Forward Landfill in Manteca, California (Attachment G) <br /> Stockpiled soil analytical data is presented in Table 3 <br />' Water generated during well sampling and equipment cleaning was pumped into a <br /> SECOR truck mounted water tank and transported to ARCO'S holding facility in West <br />' Sacramento, California, for temporary storage Purged well water was transported by <br /> Integrated Waste Management (IWM) to Seaport Environmental in Redwood City, <br /> . California for disposal <br /> 077 42070 330/Well Install report-6020 doc <br />