Laserfiche WebLink
Mr 'ferry Tarditi <br /> �} January 30, 2006 <br /> Page 3 <br />' Attachment A Laboratory reports for the groundwater samples collected for <br /> these sampling events are included as Attachment B <br /> Analytical laboratory Kiff Analytical, Inc, <br /> Davis, California <br /> (Califorrua Department of <br /> Toxic Substances Control <br /> Certification No 2336) <br /> Sample exceptions None <br /> 1 Shallow groundwater gradient 0 002 <br /> Shallow groundwater flow direction Northeast <br /> Average depth-to-water 74 20 feet <br /> Average change in shallow groundwater <br /> elevation from 3rd qtr (2005) to 4th qtr (2005) 0 44 feet <br /> DISCUSSION <br /> Based on the fourth quarter's data, the groundwater hydraulic gradient changed <br /> slightly to the northeast under a hydraulic gradient of 0 002, as shown in Figure 2 <br /> Fluctuations in the hydraulic gradient are not uncommon for this site Table 2 <br />' summarizes quarterly measurements of the hydraulic gradient <br /> The on-site supply well has been sampled on a quarterly basis since November <br /> 2002 and has never contained any detectable concentrations of any constituents of <br /> concern Therefore, sample results from this well are not included in the <br /> 1 discussions below In addition, concentrations of 1,2-DCA and EDB have not <br /> been detected and are not included in the discussion below <br /> BTEX. The reporting hmits for all constituent concentrations in MW-1 were <br /> diluted due to known high concentrations of MtBE The dilutions were necessary <br /> because the MtBE concentrations were out of the calibration range for the target <br /> constituent The reporting limits remained the same for remaining wells at 0 5 <br /> micrograms per liter (µg/L) BTEX concentrations were below their respective <br /> reporting hmits in all of the wells consistent with previous quarters Per <br /> ' PHS/EHD's request, Brown and Caldwell worked with the analytical laboratory to <br /> determine when it is feasible to quantify the BTEX constituents without damaging <br /> the equipment, especially in samples from MW-1 <br /> Thir upon wnsprrparrd to accordance usth the slandardr of the enrrsmnmental ansulliq indurTry at the time it aur prrpared R should not he <br /> eked upon by parties other than those for whom it ursr preparrd and Tien on#to The ealent of the rcope of anrk which war aulhom7d This <br /> report does notguaranlee That no addrttonal entrmnmrntal contamrnalron hryond that descnbed rn thir report e%7sir at the nae <br /> P\27000\127960 T&T Trucking GW Monitoring 2005\Reports\4th-05gtr doc <br />