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This report describes the results of a project to develop an on-board emissions and performance measurement system (OEPMS) for the quantification of carbon monoxide (CO) emissions. Researchers measured emissions from a 1990, 2.5 liter TBI engine passenger automobile over a typical suburb-to-city commute in the Minneapolis/St. Paul metropolitan area. As a test of the OEPMS, researchers measured CO emissions during cold weather cold starts and commutes at temperatures characteristic of the area's winter weather. Open-loop and closed-loop emissions of CO were measured and compared. Additionally, the effectiveness of magnetic-type block heaters was examined. Tests with the OEPMS provided a wide range of results. The OEPMS proved very durable and easily adaptable for a wide variety of testing. The OEPMS holds promise for future research into fuels, emissions reducing technologies, regulations, and commute habits in real world situations.

This report presents the results of the Phase III mitigation of site 21BL37. This multicomponent historic property is located along portions of Trunk Highway (TH) 197 in the City of Bemidji, which is located in Beltrami County, in north-central Minnesota (S.P. 0416-19). The City of Bemidji and the Minnesota Department of Transportation (Mn/DOT) have proposed the reconstruction of portions of TH 197 and Midway Drive into a system of one-way paired roadways from Roosevelt Road to Third Street NW. As a result of this road reconstruction, historic property 21-BL-37 will be adversely impacted. In order to mitigate the adverse impacts to this site, data recovery was proposed. The Minnesota Department of Transportation contracted with the Leech Lake Heritage Sites Program to complete this data recovery project.

The appendices for Phase III Data Recovery of Site 21BL37, The Midway Site, Beltrami County, Minnesota.

This study examined the physical characteristics of combustion aerosols found on Minnesota highways. It emphasized the characterization of nanoparticles (less than 50 nm) with the goal of providing real-world data for the development of engine laboratory test methods. On-road particulate matter emissions ranged between 10[to the 4th] to 10[to the 6th] particles/cm[to the 3rd] with the majority of the particles by number being less than 50 nm in diameter. High-speed traffic produced high nanoparticle number concentrations and diesel traffic further increased number concentrations. At high vehicular speeds, particulate matter emissions increase because of higher engine load and fuel consumption. Measurements made at speeds less than 20 mph showed lower number but higher volume concentrations and larger particles. Measurements made 10-30 m from the highway in residential areas approached on-road concentrations with similar size distributions and high concentrations of nanoparticles. Lower concentrations and larger particles were observed in residential areas 500 to 700 m from the highway. Fuel specific and particle/mi. emission rates were estimated from data collected on two different days. The particle/mi. emissions were about an order of magnitude greater than published figures but mass emission rates compared well with published values. However, colder temperatures, different dilution and sampling conditions and different instrumentation could explain the authors' increased estimates.

The project involved intense monitoring of two permanent plots of spring-fen vegetation at the St. Croix Watershed Research Station, Washington County, Minnesota, during the growing seasons of 1994-1999. Plot C was covered by a thin layer of mineral sediment, deposited during the heavy rains of summer 1993. At each plot, the research measured the peat surface, water-table elevations, hydraulic heads, cover by open water, and litter cover. Researchers analyzed water samples for pH, specific conductance, and absorbance, took samples for diatom analysis, and conducted vascular-plant surveys during each survey. The bryophyte flora was surveyed in 1991 and again in 1994 and 1999. The vegetation cover was photographed seasonally and initially included stereographic air photos as baseline images. Very little unidirectional change can be observed on plot C. Comparisons of the recorded changes between the plots and among the results of the seasonal surveys suggest that only the seasonal amplitude of variation on plot C might have increased. After summer 1996 relative water tables and piezometer heads drop on both plots. The hydrological measurements suggest that both plots have become significantly drier, but the vegetation appears not to have responded yet, nor has the peat build-up stopped.

A field-monitoring program began in the spring of 2000 to test the ability of a grassy swale at removing pollutants in stormwater. In 2001, a check dam was designed in conjunction with Minnesota Department of Transportation (Mn/Dot) engineers and installed into the vegetative swale. The check dam system incorporated some unique design features including a peat filter to trap nutrients and metals; and a low rock pool to trap water for biological processing. The check dam was designed for cost effectiveness and simple installation. The entire system was quantified and evaluated hydrologically and qualitatively both before and after the check dam installation. Pollutants monitored included total suspended solids, total phosphorus, and orthophosphorus. The average pollutant removal rates for the three storms following the installation of the check dam were 54 percent total phosphorus, 47 percent orthophosphorus, and 50 percent total suspended solids. The results suggest that properly designed short vegetative strips and swales, which include peat and rock check dams can substantially reduce pollutant levels from the stormwater exiting roadways.

Recent interest in detention ponds and constructed wetlands has extended to improving the quality of the runoff by reducing the concentrations of pollutants associated with stormwater runoff. Lead, zinc, copper, cadmium, phosphorus, and chloride are the contaminants of primary concern in the state of Minnesota. This study examined removal mechanisms in detention ponds. Three wetland graminoids, Glyceria grandis (reed manna grass), Scirpus validus (soft stem bulrush), and Spartina pectinata (prairie cordgrass) were studied for their phytoremediation capabilities for the six target contaminants. The uptake rates of the six target contaminants by the sediments of a detention pond were determined. These two removal processes were incorporated in an analytical model that can be used to determine critical parameters for the design of a detention pond that would produce effluent guidelines that meet requirements set by the Minnesota Pollution Control Agency. Removal rates for the three species were determined. Uptake rates were dependent on both the contaminant and species. The removal rates of the phytoremediation and the sorption sediment experiments were combined to develop a numerical model to simulate the removal mechanisms in detention ponds. This model can be used to develop design plots for a detention pond.

Phalaris arundinacea (reed canary grass), a fast-growing, rhizomatous perennial grass, is a major concern for wetland restorations in the northern US because establishment by P. arundinacea often precludes colonization by sedge meadow vegetation in restored prairie pothole wetlands. This research developed a predictive understanding of P. arundinacea (a perennial grass) dominance in prairie pothole wetland restorations and investigated potential control techniques. A large-scale field experiment demonstrated that the most effective way to control P. arundinacea is a combination of later season herbicide applications to maximize rhizome mortality, and burning to reduce the P. arundinacea seed bank density. In a mesocosm experiment, P. arundinacea growth, but not recruitment from seed, was suppressed by the presence of native species established from seed, suggesting that P. arundinacea control will likely be necessary during native species establishment. In a uniform planting study, P. arundinacea exhibited rapid rates of growth which may contribute to its aggressive nature. Controlling P. arundinacea in the most efficient way is crucial to the establishment of native vegetation in wetland restorations. Reduction of P. arundinacea is a long-term process and one that is complicated by potential reinvasion of cleared sites, so control efforts must be as effective as possible. Moreover, P. arundinacea is still widely cultivated as a forage crop and planted as a conservation species, and these populations may serve as sources of continuing propagule pressure, further complicating localized eradication efforts.

Biodiesel is a renewable fuel derived from vegetable oils or animal fats that can substitute for diesel fuel in engines or fuel oil in furnaces. Biodiesel is produced by the process of transesterification, a simple chemical process that breaks individual triglyceride molecules into three molecules of methyl esters consisting of long chain fatty acids, similar to diesel derived from petroleum. Biodiesel has proven lubricity benefits at low blends, which will be important when sulfur levels are reduced in the U.S. supply of diesel in 2006. In addition, blends of biodiesel and its usage in a pure form reduce particulate matter (PM), volatile organic compounds (VOC), as well as other toxic gases and Greenhouse Gases (GHG). Reduced emissions from biodiesel blends result from its zero sulfur content and higher oxygen content versus petro-diesel. Federal standards established by the U.S. Environmental Protection Agency (EPA) may force local authorities to implement a variety of policies to reduce VOC's, one of the precursors of ground level ozone formation, and other toxic emissions. There is also substantial concern among public health professionals concerning the formation of particulate matter (PM) from diesel engines, especially when originating from school buses, transit buses, and diesel-powered electrical generators.

The purpose of this project is to mechanize the trash collection process. There are machines available to remove trash on smooth surfaces such as concrete, but none of them are able to pick-up litter on grassy areas. The objective of this study is to design and build a machine to collect trash and litter (such as papers, plastic bags, bottles, aluminum cans, etc) lying on grassy areas alongside a road. A "Trash Harvester" would make the process easier, safer, faster, and more economical.