Laserfiche WebLink
1 <br /> Mr. M. Scott Mansholt—CEMC <br /> Fourth Quarter 2005 Groundwater Monitoring and Sampling Report and <br /> 2005 Annual Summary January 5,2006 <br /> US Can-Welty Road,Vernalis,California Page 7 of 7 <br /> concentrations up to 6,700 and 240 µg/L, respectively. SPO has been observed in wells MW-I <br /> and MW-2 since 1999. TPHg- and TPHd-range hydrocarbons appear to be present in the SPO in <br /> the vicinity of wells MW-I and MW-2. Low concentrations of PAHs have been detected in the <br /> samples from all site wells. The PRG for direct exposure to residential tap water was slightly <br /> exceeded by benzo(a)anthracene in well MW-3. <br /> SAIC recommends continued quarterly groundwater monitoring and sampling of wells MW-1 <br /> through MW-5 and WFSMW-I. Oleophilic socks in wells MW-I and MW-2 will be monitored <br /> quarterly and replaced as necessary. Once the petroleum sheen has been removed, we <br /> recommend that wells MW-1 and MW-2 be incorporated into the quarterly monitoring and <br /> 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 /> Barrett Ka sa Christopher B. Dennis, P.G. <br /> Staff Geolo Senior Geologist <br /> d�0 , <br /> Enclosures: CHRISTOPHER `. <br /> a <br /> B. <br /> Figure 1: Site Vicinity Map * DENNIS <br /> Figure 2: Site MapNo.7184 <br /> Figure 3: Potentiometric Surface Map—October 18, 2005 -Y p�% <br /> Figure 4: Petroleum Distribution in Groundwater During 2005 OP CALIF <br /> Table 1: Groundwater Elevation Data and SPO Thickness Measurements <br /> Table 2: Groundwater Chemical Analytical Results—TPH, MTBE, and BT l plres August 31-Zoof <br /> Table 3: Groundwater Analytical Results—PAI-Is <br /> Table 4: Summary of Groundwater Flow Directions and Gradients <br /> Table 5: Monitoring Well Construction Details <br /> Attachment A: Field Data Sheets <br /> Attachment B: Laboratory Chemical Analytical Report <br /> Attachment C: Second and Third Quarter 2005 Potentiometric Surface Maps <br />