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Step 6: <br />Steo 6a: Assess the Sedimentation Pond E discharge (includes sampling of the discharge, <br />• 10/13/061 <br />A water sample was obtained at the discharge of Sedimentation Pond E on 09/11/06 (prior to <br />sealing the riser). After setting for 24-hours, the coal fines had settled out of the `worst-case" <br />discharge sample from Pond E, resulting in a slightly turbid decant water in the upper portion of <br />the sample bottle. Another full sample was obtained from the dischazge box for Pond E (Site 85) <br />the next day (09/12/06). Partial analysis results (Fe and TSS (copy attached), consistent with <br />CDPS monitoring requirements for this site) for this sample have been obtained and were provided <br />to the CDRMS for review on 10/4/06. On 10/04/06, the lab was requested to complete afull- <br />suite analysis and provide results for the remaining sample volume. Final analysis results for <br />this sample were submitted to the CDRMS on 10/13/06 (copy attached for reference). <br />For the 09/12/06 and 09/22/06 water quality samples, analysis values for the normal CDPS <br />parameters (Fe, EC, and p117 and TSS were compared with recent historical data. Graphical <br />comparisons for EC and TDS (copies attached for reference) indicate that EC did not change <br />significantly immediately following the discharge (relative to historic values), but dropped <br />subsequently. All values, however, remained within the range of recent historical variance. TSS <br />values spiked at the time of the dischazge to approximately 20mg/1, but by the second sampling <br />(approximately one week later) had returned to normal historical levels (approximately 5 to 7 <br />mg/1). A significant difference was noted between the TCC sample analysis values and the <br />CDRMS values for 09/12/06 - 09/13/06. The only reasonable explanation for the difference in <br />values is that the lab may have drawn the sample(s) for analysis from the TCC sample bottles after <br />• they had set overnight, allowing the coal fines to settle-out, while the CDRMS samples were <br />analyzed in a fresh or agitated condition. Given this observation, the analysis values for the <br />CDRMS samples aze probably more representative of conditions at the time of, and immediately <br />following the coal fines dischazge, showing elevated Ca, Fe, Mg, Na, EC, TDS, TSS, and sulfate <br />values. <br />Step 6b: Assess the receiving stream water quality of Foidel Creek and Trout Creek <br />(includes sampling of Foidel Creek and Trout Creek, 10/10/06) <br />A water sample was obtained on 09/11/06 just downstream of the limit of the visible coal fines <br />migration. The downstream sample was clear. The following day (09/12/06), water quality <br />samples were obtained from several downstream stations (Sites 900, 29, 69, 1005, and 800 - <br />See attached copy of 10/04/06 a-mail identifying sites) on Foidel, Middle, Fish, and Trout Creeks. <br />Full analysis results for these sites have been obtained and were provided to the CDRMS for <br />review on 10/3/06 and 10/4/06 (copy attached for reference), along with sampling results for <br />the same sites (with the exception of Site 800) taken the week before the accidental discharge <br />occurred (09/06/06) for comparison. Weekly sampling was initiated to monitor downstream <br />water quality in order to assess potential impacts, follow the incident. The CDRMS has <br />requested analysis results for the 09/22/06 samples also be provided for comparison. Analysis <br />results for the 09/22/06 samples were submitted to the CDRMS on 10/10/06 (copy attached <br />for reference). <br />For the 09/12/06 and 09/22/06 water quality samples, analysis values for key pazameters (EC, TSS, <br />• and TDS) were compared with recent historical data. Graphical comparisons for the key <br />pazameters for Sites 900 (Foidel Creek neaz Middle Creek Shop, before confluence with <br />NOV CV-2006-006 Abatement Report 5 2/7/2007 <br />