Laserfiche WebLink
Mr. M. Scott Mansholt-CEMC <br /> Third Quarter 2006 Groundwater Monitoring and Sampling Report October 25, 2006 <br /> US Can-Welty Road Page 5 of 5 <br /> detection of phenanthrene(0.013 pg/L) in the field and field duplicate samples from WFSMW-1, <br /> which is below the most conservative WQO and ESL. SPO has been observed in wells MW-1 <br /> and MW-2 since 1999. TPHg and TPHd appear to be present in the SPO in the vicinity of wells <br /> MW-1 and MW-2. <br /> SAIC recommends reducing the groundwater monitoring and sampling of the site wells to a semi- <br /> annual schedule and removing TPHg and BTEX from the analytical suite. The dissolved-phase <br /> petroleum hydrocarbons appear to be stable and not migrating. TPHg and BTEX does not appear <br /> to be adversely affecting groundwater as these constituents have not been detected in <br /> groundwater samples collected from site wells that do not contain SPO. <br /> SAIC is preparing a work plan to properly destroy wells MW-3 and MW-4 because the water <br /> volumes in these wells are insufficient for adequate sample collection. The work plan for <br /> additional site characterization and well destruction will be submitted during the fourth quarter of <br /> 2006. <br /> Oleophilic socks in wells MW-1 and MW-2 will be monitored quarterly and replaced as <br /> necessary. When the petroleum sheen has been removed, SAIC recommends that wells MW-1 <br /> and MW-2 be incorporated into the monitoring and sampling program. <br /> CLOSING <br /> If you have any questions regarding this report, please call Chris Dennis at (916) 979-3866. <br /> Sincerely, <br /> SCIENCE APPLICATIONS INTERNATIONAL CORPORATION <br /> ONAL GLS` <br /> ` Laura Sanch� Christopher B. Dennis, P.G. 0�4 <0 <br /> Staff Geologist Senior Geologist 0 CHRISTOPHER N <br /> B <br /> B. -� <br /> DENNIS <br /> Enclosures: No.7184 <br /> Figure 1: Vicinity Map 9�`QFCA�-1F0�� <br /> Figure 2: Site Map <br /> Figure 3: Potentiometric Surface Map-Third Quarter 2006 Expires August:31�7_717 7 <br /> Figure 4: Petroleum Distribution in Groundwater-Third Quarter, 2006 <br /> Table 1: Groundwater Elevation Data and SPO Thickness Measurements <br /> Table 2: Groundwater Chemical Analytical Results-TPH, MTBE, and BTEX <br /> Table 3: Groundwater Chemical Analytical Results-PAHs <br /> Attachment A: Field Data Sheets <br /> Attachment B: Data Usability Summary and Laboratory Chemical Analytical Report <br />