ARCHIVED REPORTS_2006_1 - Laserfiche WebLink

Home Browse Search

field for dissolved oxygen, turbidity,temperature, specific conductance, and pH and recorded on well data sheets. The groundwater monitoring wells, surface water monitoring points, and leachate monitoring points (sampled monthly)were sampled in accordance with the sampling and analysis procedures detailed in Appendix B. The well data sheets,laboratory data, certificates of analyses, and chain-of-custody records for the sampling program are included in Appendix C. The laboratory analyses and field results for groundwater monitoring wells,lysimeter and leachate sampling stations are summarized in Tables 2-2 through 2-7. 2.1.2 QA/QC Results The QA/QC program completed for the second quarter 2006 water quality monitoring event included analyses of two ambient(field)blanks,two trip blanks, one equipment blank,three laboratory method blanks, and one duplicate sample. The trip, field, equipment, and blanks were analyzed for VOCs by EPA Method 8260,while method blanks were analyzed for all of the monitoring parameters. The results of the QA/QC program indicate that five VOCs(benzene, ethylbenzene,toluene,total xylenes, and MEK)were detected in the field and equipment blanks, and two VOCs (acetone and MTBE)were detected in method blanks during the second quarter 2006 monitoring event. Review of the analytical data results indicates that similar concentrations of acetone, MEK, and toluene were detected in three of the primary samples collected from the Forward Unit. These suspected field or laboratory contaminants were flagged in the summary tables. During the second quarter 2006 monitoring event, one duplicate sample was collected from well MW-23 and labeled MW-DUP. As shown on Table 2-2,with the exception of arsenic and hexavalent chromium duplicate sample analysis yielded good correlation (within 10%)with the primary sample results. Review of second quarter 2006 sampling dates and laboratory analytical certificates indicates that the laboratory analyses were completed within required holding times. Based on the results of the laboratory blank and duplicate analyses,it is concluded that the laboratory data generated for the second quarter 2006 monitoring period are generally acceptable. However, the field sampling crew was notified of the BTEX constituents in the field and equipment blanks. 2.1.3 Groundwater Elevations and Contours Prior to purging and sampling, each well'was sounded for water depth using a weighted electronic sounder to an accuracy of 0.01 foot, and the static water level was recorded on a Well Data Sheet(Appendix Q. The groundwater elevations were calculated for each well by subtracting the depth-to-water measurement from the top-of-casing reference elevation. The current groundwater elevation data for the Forward Unit is summarized in Table 2-3. D:\2003 021\ForwardAustin sp06.doe 5 GeoLogic Associates