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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.

This report presents the evaluation of chemical treatment practices known as flocculation for purifying construction site runoff of sediment, suspended solids and colloidal particles. Flocculation is generally used in combination with traditional sedimentation and filtration methods related to stormwater pollution prevention and dewatering fluid treatment. In particular, this report presents the best management practices (BMPs) for evaluation and design of flocculant treatment methods and technologies and the associated sizing for flows representative of field operations. Soil samples from across Minnesota, representing the wide range of geologic and geomorphological conditions, were used to identify differences in flocculant applicability and effectiveness.

Roadside swales are drainage ditches that also treat runoff to improve water quality, including infiltration of water to reduce pollutant load. In the infiltration study, a quick and simple device, the Modified Philip Dunne (MPD) infiltrometer, was utilized to measure an important infiltration parameter (saturated hydraulic conductivity, Ksat) at multiple locations in a number of swales. The study showed that the spatial variability in the swale infiltration rate was substantial, requiring 20 or more measurements along the highway to get a good estimate of the mean swale infiltration rate. This study also developed a ditch check filtration system that can be installed in swales to provide significant treatment of dissolved heavy metals and dissolved phosphorous in stormwater runoff. The results were utilized to develop design guidelines and recommendations, including sizing and treatment criteria for optimal performance of the full-scale design of these filters. Finally, the best available knowledge on swale maintenance was combined with information obtained from new surveys conducted to develop recommendations for swale maintenance schedules and effort. The recommendations aim toward optimizing the cost-effectiveness of roadside swales and thus provide useful information to managers and practitioners of roadways. The research results and information obtained from this study can thus be used to design swale systems for use along linear roadway projects that will receive pollution prevention credits for infiltration. This will enable the utilization of drainage ditches to their full pollution prevention potential, before building other more expensive stormwater treatment practices throughout Minnesota and the United States.

This report presents an evaluation of wastewaters derived from concrete placement and maintenance and the preparation of best management practices (BMPs). Investigation and documentation of existing practices was done to ensure application to real situations and enhancement of constructability for all BMPs. Laboratory analysis of test specimens was done to provide characterization of factors that are likely to positively or negatively influence concrete wastewater composition. Evaluation of sedimentation and filtration through and absorption by sand and geotextile materials provides a simulation of the known control techniques. Development of a constituent occurrence and control model with a strong statistical base achieved through experimental replication supports development of BMPs that are both environmentally protective and constructible.

Roadsides are a unique growing environment for turfgrasses and can be a challenge to establish and maintain. The University of Minnesota turfgrass research program has been investigating low-input turfgrasses that are better adapted for roadsides and our previous research project identified a new mixture for use on Minnesota roadsides that was able to perform adequately under pressure form road salt (MNST-12). As this new mixture was used; it became apparent that more research was needed to better understand how to improve establishment and performance by adjusting typical roadside maintenance practices. In this project; we developed a series of experiments addressing three areas: (1) pre-establishment soil amendments; (2) planting date; and (3) watering during establishment. We found that soil amendments had little effect on roadside turf performance. We found that seeding of low-input roadside mixtures such as MNST-12 should be performed in late summer; while sodding can be done throughout the growing season; assuming that soil moisture is properly maintained. Finally; based on our findings; we recommend that current MnDOT specifications for watering of new roadside turf installations should be changed; especially for mixtures with high proportions of fine fescue.

Road construction in northeast Minnesota often causes wetland impacts that require compensatory mitigation. Borrow areas excavated for road construction material can be developed into wetland mitigation sites if hydric vegetation, hydric soils and adequate hydrology are provided. Fourteen wetland mitigation sites were constructed north of Virginia, Minnesota along the U.S. Trunk Highway 53 reconstruction project corridor. The sites were established with the goal of mitigating for project impacts to seasonally flooded basin, fresh meadow, shallow marsh, shrub swamp, wooded swamp, and bog wetlands. Monitoring results indicate that the 14 mitigation sites range in their potential to receive wetland mitigation credit. All but one of the sites consistently meet wetland hydrology criteria. The sites contain a variety of plant communities dominated by wet meadow, sedge meadow, and shallow marsh. Floristic Quality Assessment (FQA) condition categories for the sites range from "Poor" to "Exceptional." Invasive plant species, particularly reed canary grass and narrow leaf cattail, are present on a number of sites and should be controlled. Tamarack and black spruce plantings have been successful on some of the drier areas and should be expanded to increase the quality and potential mitigation credit for other sites. These sites have shown the potential for creating mitigation wetlands in abandoned borrow pits in conjunction with highway construction. Adaptive management, particularly water level regulation, early invasive species control, tree planting, and continued long-term annual monitoring can make mitigation sites like these successful options for wetland mitigation credit. Continued site monitoring to determine potential for mitigation credit is recommended.

The Minnesota Department of Transportation constructed a low traffic volume road section to determine the environmental fate and effects of chemicals from tire shred materials placed below the seasonal groundwater table. The road base was constructed during November of 2002 with over seven million pounds of tire shreds enclosed in geotextile fabric in the road base. Surface and well water samples were analyzed for pH, temperature, dissolved oxygen, specific conductivity (SpCond), hardness, chemical oxygen demand (COD), total suspended solids (TSS), biochemical oxygen demand (BOD), aluminum, antimony, arsenic, barium, cadmium, total chromium, copper, iron, lead, manganese, nickel, selenium, zinc, mercury, gasoline range organics, diesel range organics, total polynuclear aromatic hydrocarbons (PAHs), and carcinogenic polynuclear aromatic hydrocarbons (c-PAHs) and eight tire specific semi-volatile organic chemicals. Selected parameter data are presented. Elevated levels of barium, iron, and manganese were measured in all of the monitoring wells but not in the background well or surface water. The tire shreds contributed some PAHs to the surface water but in very low concentrations. Four tire material semi-volatile organics were detected in well water but not surface water samples.

Blowing and drifting snow on Minnesota's roadways is a transportation efficiency and safety concern. Establishing standing corn rows and living snow fences improves driver visibility, road surface conditions, and has the potential to lower costs of road maintenance as well as accidents attributed to blowing and drifting snow. It also has the potential to sequester carbon and avoid the carbon emissions of snow removal operations. In recent years the Minnesota Department of Transportation (MnDOT) has paid farmers to leave standing corn rows to protect identified snow problem roadways. They have paid farmers $1.50 per bushel above market price. With increasing demand for corn to fuel the ethanol industry, paying $1.50 per bushel above market price may not be sufficient incentive for leaving standing corn rows. Also, with MnDOT's memorandum of understanding with USDA to plant living snow fences through the Conservation Reserve Program (CRP), now is an opportune time to review MnDOT's annual payment structure to farmers and prepare a new one. This project has: 1) developed a calculator to estimate payments for farmers that includes consideration of safety and snow removal cost savings; 2) estimated potential income from carbon payments; 3) worked closely with MnDOT engineers and plow operators, estimated the safety and snow removal costs and carbon emissions avoided by MnDOT through establishing living snow fences; and 4) evaluated farmers' willingness to establish living snow fences and identified farmers/landowners' constraints to adoption. Data is provided to MnDOT to assist staff in its decision making related to their Living Snow Fence Program.

The goal of this project is to develop a sub-soiling regimen that will enhance and be compatible with existing erosion control measures. This project is important in minimizing the effect of construction-induced compaction on the urban and rural landscape. This activity, if successful, will become a building block for use in Best Management Practices (BMPs) that will ensure full vegetative growth post construction, and save on the cost of reapplication of erosion control measures. For a good comparative study, several sites were selected for typical slope and soil type. The study shows that there are low cost benefits to deep tillage of ROW. Heavy clay soils are problematic in that improvements in infiltration could not be detected after a single tillage operation. In lighter sandy soils, the benefits of tillage are such that significant increases in infiltration can be gained following a single pass tillage operation. The differences in tillage implement used could not be detected. The post-tillage aesthetic appeal when using a non-inverting plow (Kongskilde Paraplow) was apparent in this study. The vegetation was largely undisturbed following tillage, and this would be beneficial in preventing erosion on slopes. The ripper and the DMI inverted more soil, and therefore the tillage operation was less appealing to motorists. The relatively low cost of ownership and operation for the tillage is overshadowed by the high land cost when new roads are constructed. Tillage would be beneficial on lighter soils, however the "utility congestion" that is likely in such a scenario would make machinery management difficult.

Environmental justice is concerned with a variety of public policy efforts to ensure that adverse human health or environmental effects of governmental activities do not fall disproportionately upon minority populations and low‐income populations. In the realm of transportation, environmental justice means that transportation system changes such as road improvements are studied carefully to determine the nature, extent, and incidence of probable impacts, both favorable and adverse. The objective of this project has been to develop a series of practical indicators of economic, social, and environmental impacts related to transportation system changes. Comparing the spatial incidence of these impacts with the locations of low‐income populations and minority populations, it is possible to assess whether the impacts would adversely and disproportionately affect these populations. Our intent is to help make it possible for everyone who is likely to be affected by a particular transportation system change to understand the expected types and magnitudes of anticipated impacts. The objective of such an understanding is to enable those who would be affected to determine which impacts would be most important to them.

In this project, researchers studied mycorrhizal and vegetational characteristics at prairie and wetland restoration areas. Study objectives included the following: * quantifying the effect of fungal inoculum on plant communities at a Minnesota Department of Transportation (Mn/DOT) prairie restoration site near Cambridge, Minn. * evaluating the prairie forb germination rates * monitoring revegetation at prairie and wetland restoration sites * characterizing mycorrhizal status of native wetland and prairie areas for comparison to the restored sites * producing fungal inoculum for incorporation into further reclamation areas. Findings indicated that 15 months after planting, fungal inoculation resulted in significantly greater cover by native plant species than seen in control plots. At this site, mycorrhizal inoculation benefited the prairie restoration effort by encouraging earlier, more extensive establishment of the planted species. Ongoing studies at this site will determine the long-term effects of mycorrhizal inoculation on the plant community. The report also presents specific recommendations for future restoration efforts. The studies of mycorrhizae in native prairies and wetlands provide further data for a baseline against which to compare restored areas. In addition, fungal inoculum produced in this project has been incorporated into restoration plots at another Mn/DOT site.

As the cost of transporting people increases, questions about paying for the accompanying air and noise pollution increase. This report investigates the distribution impacts of environmental pricing policies on groups in the Twin Cities. The study uses data on travel behavior in the Twin Cities to examine the distributional impacts of three types of environmental pricing policies: a $.65 optimal downtown, peak period congestion fee; a 10 percent gasoline tax; and a 50 percent transit fare reduction. It evaluates each policy in terms of aggregate welfare costs, revenues, emissions reductions, and cost-effectiveness and looks at distributional impacts by using four groupings--income, region, gender, and age. The study found that the congestion fee and gasoline tax are regressive, with the burdens of these taxes increasing with income and decreasing as shares of income. The transit subsidy, on the other hand, disproportionately benefits low-income individuals. Other findings show the advantages and disadvantages to urban and suburban commuters and noncommuters and senior citizens.

Transportation and its supporting infrastructure have significant economic, social, and environmental impacts. Using more sustainable methods to design, construct, and preserve roads will better protect the environment and meet our ongoing needs. Mn/DOT and our partners in government, industry, and academia have been researching and implementing ways to make our roads greener, while maintaining or improving roadway quality.

Regulations require that stormwater pollution prevention plans be developed for construction activities that disturb an area that is equal to or greater than one acre. Different strategies, including a combination of practices, can be used to develop these plans. The WATER model was a tool developed from a previous project to assess the effectiveness of different on-site sediment control practices. This model is expanded in this study to consider offsite practices, to include processes at the watershed scale, and to allow spatial data sets to be integrated into the simulation framework. Routines to simulate the impact of off-site practices of rock check dams, vegetative filters, and detention ponds are added to the WATER model. The detention pond model has been modified to allow rock and gravel infiltration filters to be included as an off-site practice. Two different algorithms are used: (1) the Protocol Method based purely on empirical data and (2) the Process-Based Method using process-based relationships developed for porous media flow.

A study was conducted to generate knowledge on the environmental effects of de-icing salt, particularly sodium chloride (NaCl), on water quality in Minnesota, especially the Twin Cities Metropolitan Area (TCMA). The Mississippi River receives substantial sodium chloride inputs from the Minnesota River and waste water treatment plants as it passes through the TCMA. In addition, road salt applications in the TCMA use about 350,000 short tons of NaCl every year. A chloride budget at the scale of the TCMA and on individual sub-watersheds in the TCMA indicates that about 70% of the road salt applied in the TCMA is not carried away by the Mississippi River. Rates of seasonal road salt use are correlated with snowfall, road miles and population. Salinity in TCMA lakes increases in winter and decreases in summer. Ionic composition of dissolved substances in lakes of the TCMA suggests unnaturally high sodium and chloride concentrations compared to lakes and other water bodies in the Midwestern U.S. Data indicate a rising trend in urban lake water salinity over the last 30 years. Shallow groundwater in the TCMA, especially near major roadways, has started to show increasing chloride concentrations. Salinity trends in lakes and shallow aquifers of the TCMA are of concern.

This manual provides guidance for methods of evaluating projects to assess the potential of encountering acid-generating materials in northern Minnesota. Methods for field reconnaissance; preliminary testing; characterization sampling efforts; interpretation of results; approaches for mitigation; and approaches for project monitoring are included.