Browsing by Author "Post, Sara P"

Now showing 1 - 6 of 6
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    Geological and Geochemical Reconnaissance for Rare Earth Element Mineralization in Minnesota
    (University of Minnesota Duluth, 2014) Hauck, Steven A; Heine, John J; Severson, Mark J; Post, Sara P; Chlebecek, Sara; Monson Geerts, Stephen D; Oreskovich, Julie A; Gordee, Sarah M
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    Minnesota Taconite Workers Health Study: Environmental Study of Airborne Particulate Matter in Mesabi Iron Range Communities and Taconite Processing Plants - Lake Sediment Study
    (University of Minnesota Duluth, 2019-12) Zanko, Lawrence M; Reavie, Euan D; Post, Sara P
    Atmospheric deposition of airborne particulate matter such as fugitive dust contributes to sediment that accumulates at the bottom of a lake. Because of this phenomenon, lake sediment can provide an historic mineralogical and chemical record of what may have been in the air at the time of its atmospheric deposition. This point is important, because the NRRI’s role in the Minnesota Taconite Workers Health Study (MTWHS) was to not only help answer the question “What is in the air?” by conducting present-day in-plant and community air sampling, but – and even more challengingly – to potentially answer the question “What was in the air, when?” by collecting and analyzing historic samples. Lake sediment was the only historic sampling medium available that could allow the investigators to make an attempt to assess what might have been present in the air in the past on Minnesota’s Mesabi Iron Range (MIR). The NRRI therefore core-sampled, age-dated, and characterized intervals of sediment from two MIR lakes – Silver Lake in Virginia, on the central MIR, and “North-of-Snort” Lake on the eastern end of the MIR, near Babbitt (Fig. i). The objective was to determine if fugitive mineral dust generated by past iron ore/taconite mining activity could be discerned in mineral particulate matter (PM) deposited and preserved in the sediment of both lakes.
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    MnDOT Highway 169 2015 Drilling Project
    (University of Minnesota Duluth, 2017-06) Heine, John J; Patelke, Marsha Meinders; Buschette, Michael; Leu, Adam; Maly, Craig C; Gordee, Sarah M; Chlebecek, Sara; Lee, Aubrey; Post, Sara P
    The Natural Resources Research Institute (NRRI) Economic Geology Group was contracted by the Minnesota Department of Transportation (MnDOT) [Project Number 0005269] to provide onsite drilling supervision, core logging and sampling, and geochemical studies related to proposed construction along Highway 169 east of Soudan, Minnesota. The goal of this project was to provide MnDOT the data required to produce a mitigation plan for the Highway 169 Eagles Nest project. MnDOT, working with the Minnesota Department of Natural Resources (DNR) and Golder Associates, was responsible for developing the guidelines for this work with the help of the Highway 169 Technical Working Group (Minnesota Pollution Control Agency, Minnesota Department of Health, US Corps of Engineers, Environmental Protection Agency, and NRRI). Golder Associates (Seattle, WA office) was responsible for developing the mitigation plan for bedrock roadcuts along the reroute. This work was a continuation of the studies by Severson and Heine (2010, 2012) and Heine (2015) which examined the bedrock outcrops along three proposed Highway 169 reroutes and alternatives. Severson and Heine (2012) concluded that drilling would be needed in the potential bedrock roadcuts along the reroute corridor to fully characterize the geology as required in the mitigation plan.
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    Mobile Water Treatment Demonstration System for Sulfate Reduction
    (University of Minnesota Duluth, 2022-08) Cai, Meijun; Rao, Shashi; Post, Sara P; Hanson, Adrian; Chun, Chan Lan; Johnson, Lucinda B; Hudak, George J; Weberg, Rolf
    The State of Minnesota adopted a sulfate standard of 10 mg/L for wild rice waters in 1973. Although under review, current technology for achieving this standard is a challenge for small industries and municipalities. Membrane-based technologies such as nanofiltration and reverse osmosis are capable of treating water to reach the Minnesota wild rice water sulfate standard; however, they typically require high capital and operation costs. Therefore, there is a need to develop cost-effective sulfate treatment alternatives. The Natural Resources Research Institute (NRRI) has developed a treatment system based on barite chemical precipitation reactions to reduce sulfate levels in water from 60-200 mg/L to below 10 mg/L. This system was demonstrated at bench-scale batch and continuous tests. The data collected from these lab tests were used to scale up the process to a trailer-based modular demonstration treatment system. This study highlights the outcomes of field pilot tests conducted by NRRI using this treatment system. The objectives of the field pilot trials were to: (1) Evaluate the efficacy of the chemical precipitation process when scaled up from 200 ml/min to 2 GPM; (2) Study the effect of co-existing chelating organics of the raw wastewater on barite precipitation reactions; (3) Optimize the chemical reagent dosage levels; (4) Investigate the potential of reusing process sludge to promote precipitation reactions; (5) Identify strategies to minimize scale formation on process equipment; and (6) Estimate the chemical reagent costs. The pilot tests were conducted using effluent from two municipal wastewater treatment plants (WWTP)—the Virginia WWTP and the Grand Rapids WWTP in northeastern Minnesota—from June 2021 until October 2021.
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    Non-ferrous Geology along the Highway 53 Relocation near Virginia, MN
    (University of Minnesota Duluth, 2015) Heine, John J; Patelke, Marsha Meinders; Post, Sara P; Maly, Craig C
    This report outlines the non-ferrous work done in the area of the Highway 53 relocation near Virginia, MN. At the request of the mineral lease holder (Vermilion Gold Inc.), an examination of the gold potential in the area of the new road was completed. Vermilion Gold Inc. located ten exploration diamond drill hole sites which they believed were necessary to characterize the area. Drilling occurred during fall 2013 and was conducted by Idea Drilling. The drilling and subsequent work by Natural Resource Research Institute, University of Minnesota Duluth (NRRI) was funded by the Minnesota Department of Transportation (Mn/DOT) as part of the relocation work for the highway. Logging and sample preparation were completed at the NRRI Coleraine Minerals Research Laboratory (CMRL) in Coleraine, MN.
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    Western Mesabi Iron Resources of the Future
    (University of Minnesota Duluth, 2022-09-15) Johnson, Rodney C; Mlinar, Matthew A; Spigarelli, Brett P; Post, Sara P
    The purpose of this study was to initiate a long-term comprehensive characterization program of the remaining iron resources of the Mesabi Iron Range to provide a foundation for the future iron industry in Minnesota. This data is being used to direct research in the areas of reducing reliance on fossil fuels, reducing emissions, and to identify and develop value-added iron products that could be produced from underutilized portions of Minnesota iron resources. Two complete sections of the iron formation were analyzed in this study. The results have contributed to a better understanding of the mineralogical variability within the iron formation; the impacts of oxidation on iron product quality; the potential for new iron-based products; and the presence of trace elements.