Laserfiche WebLink
OBSERVATIONS AND ANALYTICAL RESULTS <br /> No free-phase liquid hydrocarbon layer or sheen was seen on the water tape during the <br /> measurement of any of the groundwater monitoring wells In addition, all purged and sampled <br /> water appeared to be clear and lacked any odor (Appendix B) <br /> The depth-to water measurements indicate that the seasonal rainfall had increased the <br /> standing height of water in each monitoring well by nearly five feet as compared to the <br /> December samplings The rise in the water table has not changed the gradient however, it <br /> continues to slope toward the north-northeast at approximately one foot per three hundred feet <br /> (Figure 2) <br /> The laboratory results are non-detect for BTEX (<0 5 micrograms per liter - µg/L) for all <br /> of the groundwater samples extracted from the wells The laboratory results are also non-detect <br /> for TPH-diesel (<50 µg/L) in three of the wells (MW-04, MW-05 and MW-07) but report finding <br /> low levels of TPH-diesel in MW-06 (71 µg/L) and in MW-08 (58 µg/L) The results of the <br /> laboratory analyses are presented in Table 1 A copy of the laboratory analytical report and the <br /> chain-of-custody record is included in Appendix A <br /> DISCUSSION <br /> Sampling of the groundwater monitor wells has been ongoing since the middle of 2003 <br /> In twenty-six of the thirty-one samples analyzed for TPH-diesel to date, the laboratory results <br /> have consistently reported concentrations below the laboratory detection limit (50 pg/L) In the <br /> five remaining samples, predominantly from the same two wells (MW-06 & MW-08), the <br /> concentrations were found to be just slightly above the detection limit <br /> CONCLUSION <br /> The results present no clear picture to explain the inconsistent results It is not certain if <br /> these detections are due to actual groundwater issues or sample contamination in the field RMC <br /> intends to closely follow all future samplings to reevaluate Its sampling techniques, while <br /> continuing to monitor and evaluate the future groundwater sample results <br /> Quarter 1 Sampling Report-2005 <br /> Page 2 of 2 <br />