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Minnesota, United States

Magner J.A.,Minnesota Pollution Control Agency MPCA | Hansen B.J.,University of Minnesota | Anderson C.,University of Minnesota | Wilson B.N.,University of Minnesota | Nieber J.L.,University of Minnesota
ASABE - 9th International Drainage Symposium 2010, Held Jointly with CIGR and CSBE/SCGAB | Year: 2010

Selected ditches in Minnesota and throughout the upper Midwestern USA have become morphologically unstable via geotechnical failure, channel enlargement and/or aggradation. Most ditches adjust channel form over time; some remain stable whereas other ditches unravel and require thousands of dollars worth of maintenance. Unstable ditch channels in Minnesota have also resulted in loss of biotic habitat and excessive sediment transport to downstream water bodies resulting in an impaired waters designation under the Clean Water Act, Section 303(d). There are climatic, geologic and land use reasons why ditch channels become unstable over time. We provide an assessment tool for evaluating channel and bank processes occurring within a given ditch reach. The tool systematically considers factors driving ditch channel instability and offers potential remediation actions related to nutrient attenuation. MADRAS is a relatively rapid assessment tool that considers both channel hydraulics and geotechnical factors associated with channel instability. A ditch reach must be walked by an evaluator to gather field evidence and determine processes such as toe slope erosion, bank seepage, bank angle, vegetation, slumping and the relative in-channel sediment storage and transport. Observations of physical processes and hydrologic pathways are documented and then interpreted to diagnosis the ditch condition. Localized ground water seepage induced slumps require a different solution compared to bank slumping induced by systematic hydrologic changes within a watershed. Ditch reach assessment offers the local drainage authority a means to define and prioritize the nature of ditch channel instability and a framework for guiding the maintenance response to unstable ditches. Source


Lenhart C.F.,University of Minnesota | Brooks K.N.,University of Minnesota | Heneley D.,University of Minnesota | Magner J.A.,University of Minnesota | Magner J.A.,Minnesota Pollution Control Agency MPCA
Environmental Monitoring and Assessment | Year: 2010

The Minnesota River Basin (MRB), situated in the prairie pothole region of the Upper Midwest, contributes excessive sediment and nutrient loads to the Upper Mississippi River. Over 330 stream channels in the MRB are listed as impaired by the Minnesota Pollution Control Agency, with turbidity levels exceeding water quality standards in much of the basin. Addressing turbidity impairment requires an understanding of pollutant sources that drive turbidity, which was the focus of this study. Suspended volatile solids (SVS), total suspended solids (TSS), and turbidity were measured over two sampling seasons at ten monitoring stations in Elm Creek, a turbidity impaired tributary in the MRB. Turbidity levels exceeded the Minnesota standard of 25 nephelometric units in 73% of Elm Creek samples. Turbidity and TSS were correlated (r 2=0.76), yet they varied with discharge and season. High levels of turbidity occurred during periods of high stream flow (May-June) because of excessive suspended inorganic sediment from watershed runoff, stream bank, and channel contributions. Both turbidity and TSS increased exponentially downstream with increasing stream power, bank height, and bluff erosion. However, organic matter discharged from wetlands and eutrophic lakes elevated SVS levels and stream turbidity in late summer when flows were low. SVS concentrations reached maxima at lake outlets (50 mg/l) in August. Relying on turbidity measurements alone fails to identify the cause of water quality impairment whether from suspended inorganic sediment or organic matter. Therefore, developing mitigation measures requires monitoring of both TSS and SVS from upstream to downstream reaches. © 2009 Springer Science+Business Media B.V. Source


Hickle G.T.,Minnesota Pollution Control Agency MPCA
Resources, Conservation and Recycling | Year: 2014

Extended producer responsibility seeks to integrate environmental impacts into the product lifecycle and achieve greater economic efficiencies in the management of products at end of life. For such integration to be actualized, however, producers may need to be accorded greater programmatic authority and flexibility than is often in some EPR policies that stipulate defined roles for other entities along the product chain. The proper allocation of responsibility among the parties and, in particular, the roles of the producers and local authorities remains a principal component of EPR policy construction. The analysis outlines four broad categories of financial and programmatic responsibility that currently reside within EPR programs in North America. The article concludes with recommendations for a research agenda to further define the governance characteristics that result in effective and efficient EPR programs. © 2014 Elsevier B.V. All rights reserved. Source


Oliaei F.,Cambridge Environmental Consulting | Oliaei F.,Minnesota Pollution Control Agency MPCA | Kriens D.,Minnesota Pollution Control Agency MPCA | Kriens D.,Harvard University | And 2 more authors.
Environmental Science and Pollution Research | Year: 2013

Perfluorooctane sulfonate (PFOS) and PFOS-related substances have been listed as persistent organic pollutants in the Stockholm Convention. From August 2012, Parties to the Convention needed to address the use, storage, and disposal of PFOS-including production sites and sites where PFOS wastes have been deposited-in their national implementation plans. The paper describes the pollution in Minnesota (USA) caused by the 3M Company at one of the largest per/polyfluorinated chemical (PFC) production facilities. From early 1950s until the end of 2002, when 3M terminated PFOS and perfluorooctanoic acid (PFOA) production, PFOS, PFOA, and other PFC production wastes were disposed around the plant and in local disposal sites. Discharges from the site and releases from deposits caused widespread contamination of ground and surface waters including local drinking water wells. Fish in the river downstream were contaminated with PFOS to levels that led to fish consumption advisories. Human exposures resulted from ingesting contaminated drinking water, requiring installation of water treatment facilities and alternate water supplies. The critical evaluation of the assessments done revealed a range of gaps in particular of human exposure where relevant exposure pathways including the entire exposure via food have not been taken into consideration. Currently, the exposure assessment of vulnerable groups such as children or Hmong minorities is inadequate and needs to be improved/validated by epidemiological studies. The assessment methodology described for this site may serve-with highlighted improvements-as a model for assessment of other PFOS/PFC production sites in the Stockholm Convention implementation. © 2012 Springer-Verlag Berlin Heidelberg. Source

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