5.2. SR 09-22-1997 - Laserfiche WebLink

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DRAFT sediment collected in the auger was placed in a covered stainless steel bowl and thoroughly composited. The bucket auger, extension rods and PVC casing were all cleaned between sample locations using non-phosphate solution and clelonlzecl water, gecllment samples were placecl on ice in a cooler and transported to the analytical laboratory within 24 hours of sampling. Samples were also transported to the soils engineering testing laboratory. 2. Chemical Analyses Samples collected from the upper 6-inches of sediment were analyzed for the following "Tier I" parameters: moisture content, ammonia nitrogen, kjeldahl nitrogen, total phosphorus, and total organic carbon (TOC). Total organic carbon and kjeldahl nitrogen were analyzed within 48 hours and the results evaluated by the MPCA to determine at which sampling sites "Tier II" analysis was required. "Tier II" parameters include metals, cyanide, phenol, pesticides, herbicides, polychlorinated bi-phenyls (PCBs), and polyaromatic hydrocarbons (PAHs). A complete list of MPCA selected "Tier II" parameters is included in Appendix A along with the lake sediment chemical data. Upon review of the "Tier I" data, the MPCA selected sampling locations #2 and #3 for additional "Tier II" analysis. Sediment from sampling locations #2 and #3 had the highest TOC concentrations of the four sampling locations and therefore the highest potential for containing contaminants of concern. Samples collected for "Tier II" analysis were composited from sediment collected at depths between 0-4 feet. No organic parameters were detected at either sampling location #2 or #3. A number of inorganic "Tier II" parameters were detected at both sampling locations, within the normal background range for sediment. The MPCA has indicated that they have no concerns with the quality of the sediment sampled. N:\0598\01 ~ELKRIVER.KPT-rlb 4