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II. Description of Investigation and Results <br /> p b <br /> A. LAKE SEDIMENT SAMPLING <br /> 1. Sediment Sampling Procedures <br /> Four sediment sampling locations were identified in cooperation with the Minnesota Pollution <br /> Control Agency (MPCA) to characterize sediment within Lake Orono in preparation for <br /> anticipated future dredging activities. Sampling locations are indicated on Figure 3. Per the <br /> MPCA's suggestion, samples from the upper 6-inches of sediment were obtained with a Ponar <br /> dredge at each of the four sampling locations. Sediment cores were also collected to a depth of <br /> 4 feet by two methods described below. <br /> i <br /> Sediment coring was completed using a modified WiIdco K-B stainless steel core sampler. This <br /> core sampler collected sediment samples that were 2 inches in diameter and 20 inches in length. <br /> The K-B sampler utilized clear cellulose acetate butyrate (CAB) core liners and eggshell-type <br /> core catchers. The sampler was manually lowered into the water and penetrated the sediments by <br /> either the force of its own weight or by being pushed or driven as dictated by sediment <br /> consistency. After the sampler reached maximum penetration, it was carefully retrieved and <br /> disassembled. The filled liner was then removed from the core tube, capped and labeled. The <br /> core sampler was then cleaned using a non-phosphate detergent solution and deionized water <br /> rinses and reassembled with new liner tube. <br /> Sediment samples were also collected utilizing a modified 3-inch stainless steel AMS bucket <br /> auger. A 4-inch diameter PVC casing was first driven into the sediment. The bucket auger was <br /> then utilized to manually bore into and collect the sediment from within the PVC casing. The <br /> N:W 596D I\ELKRI VER RPT-NCW 2 <br />