Open Access. Powered by Scholars. Published by Universities.®

Physical Sciences and Mathematics Commons

Open Access. Powered by Scholars. Published by Universities.®

Articles 1 - 30 of 83

Full-Text Articles in Physical Sciences and Mathematics

Fate And Transport Of Per- And Polyfluoroalkyl Substances (Pfas) At Aqueous Film Forming Foam (Afff) Discharge Sites: A Review, Jeffery T. Mcgarr, Eric G. Mbonimpa, Drew C. Mcavoy, Mohamad R. Soltanian May 2023

Fate And Transport Of Per- And Polyfluoroalkyl Substances (Pfas) At Aqueous Film Forming Foam (Afff) Discharge Sites: A Review, Jeffery T. Mcgarr, Eric G. Mbonimpa, Drew C. Mcavoy, Mohamad R. Soltanian

Faculty Publications

Per- and polyfluorinated alkyl substances (PFAS) are an environmentally persistent group of chemicals that can pose an imminent threat to human health through groundwater and surface water contamination. In this review, we evaluate the subsurface behavior of a variety of PFAS chemicals with a focus on aqueous film forming foam (AFFF) discharge sites. AFFF is the primary PFAS contamination risk at sites such as airports and military bases due to use as a fire extinguisher. Understanding the fate and transport of PFAS in the subsurface environment is a multifaceted issue. This review focuses on the role of adsorbent, adsorbate, and …


Filter-Based Air Sampler Capable Of Integration Into Small Unmanned Aerial Vehicles, Robert M. Eninger, Stepanie A. Ohms, Jeremy M. Slagley Apr 2023

Filter-Based Air Sampler Capable Of Integration Into Small Unmanned Aerial Vehicles, Robert M. Eninger, Stepanie A. Ohms, Jeremy M. Slagley

AFIT Patents

A filter-based air sampler, more specifically a filter-based air sampler capable of integration into small unmanned aerial systems is disclosed. The filter-based air sampler may include a filter assembly which has as its component parts: an open faced air intake component, a filter, and a filter support that has a central supporting grid. The filter assembly may joined to the housing of a fan, such as a centrifugal fan, with the supporting grid of the filter support being disposed over the air inlet of the fan.


Improving Data-Driven Infrastructure Degradation Forecast Skill With Stepwise Asset Condition Prediction Models, Kurt R. Lamm, Justin D. Delorit, Michael N. Grussing, Steven J. Schuldt Aug 2022

Improving Data-Driven Infrastructure Degradation Forecast Skill With Stepwise Asset Condition Prediction Models, Kurt R. Lamm, Justin D. Delorit, Michael N. Grussing, Steven J. Schuldt

Faculty Publications

Organizations with large facility and infrastructure portfolios have used asset management databases for over ten years to collect and standardize asset condition data. Decision makers use these data to predict asset degradation and expected service life, enabling prioritized maintenance, repair, and renovation actions that reduce asset life-cycle costs and achieve organizational objectives. However, these asset condition forecasts are calculated using standardized, self-correcting distribution models that rely on poorly-fit, continuous functions. This research presents four stepwise asset condition forecast models that utilize historical asset inspection data to improve prediction accuracy: (1) Slope, (2) Weighted Slope, (3) Condition-Intelligent Weighted Slope, and (4) …


Application Of Machine Learning To Predict The Performance Of An Emipg Reactor Using Data From Numerical Simulations, Owen Sedej, Eric G. Mbonimpa, Trevor Sleight, Jeremy Slagley Mar 2022

Application Of Machine Learning To Predict The Performance Of An Emipg Reactor Using Data From Numerical Simulations, Owen Sedej, Eric G. Mbonimpa, Trevor Sleight, Jeremy Slagley

Faculty Publications

Microwave-driven plasma gasification technology has the potential to produce clean energy from municipal and industrial solid wastes. It can generate temperatures above 2000 K (as high as 30,000 K) in a reactor, leading to complete combustion and reduction of toxic byproducts. Characterizing complex processes inside such a system is however challenging. In previous studies, simulations using computational fluid dynamics (CFD) produced reproducible results, but the simulations are tedious and involve assumptions. In this study, we propose machine-learning models that can be used in tandem with CFD, to accelerate high-fidelity fluid simulation, improve turbulence modeling, and enhance reduced-order models. A two-dimensional …


Natural Infrastructure Alternatives Mitigate Hurricane-Driven Flood Vulnerability: Application To Tyndall Air Force Base, Kiara L. Vance Mar 2022

Natural Infrastructure Alternatives Mitigate Hurricane-Driven Flood Vulnerability: Application To Tyndall Air Force Base, Kiara L. Vance

Theses and Dissertations

Hurricane frequency and magnitude intensification are expected over the remainder of the twenty-first century. Uncertainty in future projections requires that coastal communities approach adaptation decisions with caution. Traditional approaches are costly and inflexible. Soft policy adaptations are largely unenforceable. Hard, natural adaptations have emerged as an opportunity to partially mitigate the growing risk of extreme flooding, without the large investments required for traditional approaches, where natural infrastructure already exists. Existing literature for natural adaptations has not leveraged intensification expectations for hurricane events. This research uses multihazard damage evaluation software and spatial analysis to investigate placement of dredged sediment as a …


Efficiency Mapping And Determination Of Reliability, Resiliency And Vulnerability Of Atmospheric Water Generators In The United States, Erica F. Sadowski Mar 2022

Efficiency Mapping And Determination Of Reliability, Resiliency And Vulnerability Of Atmospheric Water Generators In The United States, Erica F. Sadowski

Theses and Dissertations

Atmospheric Water Generators (AWG) extract water from the air using one of three available technologies: refrigeration, sorption, and fog harvesting. A refrigeration device works like a dehumidifier and works best in conditions above 60% relative humidity. A sorption device utilizes a desiccant to extract the water vapor from the air and works in very low humidity levels. A fog harvesting device utilizes a mesh to capture the water vapor from the air and requires 100% relative humidity. In this research, I analyze two refrigeration-based devices and one sorption-based device and their efficacy in providing supplemental water supply. Due to climatological …


A Thematic And Reference Analysis Of Touchless Technologies, Eric R. Curia Mar 2022

A Thematic And Reference Analysis Of Touchless Technologies, Eric R. Curia

Theses and Dissertations

The purpose of this research is to explore the utility and current state of touchless technologies. Five categories of technologies are identified as a result of collecting and reviewing literature: facial/biometric recognition, gesture recognition, touchless sensing, personal devices, and voice recognition. A thematic analysis was conducted to evaluate the advantages and disadvantages of the five categories. A reference analysis was also conducted to determine the similarities between articles in each category. Touchless sensing showed to have the most advantages and least similar references. Gesture recognition was the opposite. Comparing analyses shows more reliable technology types are more beneficial and diverse.


A Post-Disaster Construction Portfolio Optimization Framework For Tyndall Afb Rebuild Post Hurricane Michael, Andre J. May Mar 2022

A Post-Disaster Construction Portfolio Optimization Framework For Tyndall Afb Rebuild Post Hurricane Michael, Andre J. May

Theses and Dissertations

Natural disasters such as hurricanes, earthquakes, tsunamis, and extreme flooding cause severe social and economic disruptions. Restoration of social and revenue-generating services often requires extensive reconstruction, from the facility to the campus scale. For multi-facility portfolios, decision-makers must prioritize post-disaster reconstruction activities appropriately to ensure facilities and infrastructure are restored. In addition, any expansion or new construction initiatives are ideally completed in order of decision-maker and community preference. Most post-disaster optimization and decision framework research consider a single stakeholder as guiding decisions related to a project portfolio. However, these portfolio prioritization frameworks ignore the effect of multiple stakeholders and competing …


A Critical Review Of Climate Change On Coastal Infrastructure Systems, Gregory J. Howland Jr. Mar 2022

A Critical Review Of Climate Change On Coastal Infrastructure Systems, Gregory J. Howland Jr.

Theses and Dissertations

This thesis is a response to climate threats identified by DoD report on Climate Change in 2019. A critical review of climate change literature related to coastal infrastructure was conducted to synthesize past research and to inform future research. This review intends to inform how climate change may impact infrastructure systems, how those impacts are evaluated, can the investigation be improved, and what can stakeholders learn from the outcomes. The end goal is to find climate change mitigation strategies and adaptation measures, or identify the easiest path to get to that end. The compiled information will inform civilian and military …


Hydrologic Profiles And Geospatial Trend Analysis Evaluating Recurrent Flooding At Coastal U.S. Air Force Installations, Dylan D. Bechen Mar 2022

Hydrologic Profiles And Geospatial Trend Analysis Evaluating Recurrent Flooding At Coastal U.S. Air Force Installations, Dylan D. Bechen

Theses and Dissertations

Military installations are exposed to numerous threats, including a changing climate and the risk of recurrent flooding. The four components of recurrent flooding are sea-level rise, tidal fluctuations, storm surges, and precipitation. This research analyzed 40 years of historical precipitation and tidal data at 17 coastal U.S. Air Force installations using indicators of both peak and threshold exceedances to identify long-term temporal trends in the hydrologic components that make up recurrent flood risk, establishing an installation’s “hydrologic profile” which can be used to better inform decision makers when evaluating portfolio-wide adaptation strategies and prioritization of long-term infrastructure investments.


A Framework For Assessing Facility-Level Vulnerability And Risk To Extreme Weather Events, Blake A. Gawlik Mar 2022

A Framework For Assessing Facility-Level Vulnerability And Risk To Extreme Weather Events, Blake A. Gawlik

Theses and Dissertations

Intensifying extreme weather events, tied to the rise in the global average temperature, put global built infrastructure at risk. This presents a daunting challenge for organizational leaders who are tasked to determine how best to adapt current infrastructure to uncertain future events. To develop adaptation plans and policies, vulnerability and risk must be downscaled to an actionable scale, such that planners, designers, and engineers can make adaptation recommendations. However, previous research has largely assessed risk at coarser scales, e.g., regional, national, or global. These assessments are informative, but do not help those tasked to lead adaptation to make detailed, actionable …


Carbon Estimation And Decision Making In Usaf Acquisition, Robert F. Gray Mar 2022

Carbon Estimation And Decision Making In Usaf Acquisition, Robert F. Gray

Theses and Dissertations

Recent executive orders and international agreements require the United States to significantly reduce its carbon and greenhouse gas emissions. The DoD is a significant contributor to the carbon emissions of the USA and will be required to reduce the emissions. Therefore, in order to make appropriate programmatic decisions the DoD needs to develop an appropriate method for estimating carbon and making programmatic decisions; trading-off carbon emissions with the traditional cost-schedule-performance metrics. This thesis examines the possibility of developing a model that can be used to estimate the carbon footprint of producing a system before detailed engineering designed have been complete.


Climate Change Risk To Coastal Airfield Stormwater Systems, Jedidiah R. Langlois Mar 2022

Climate Change Risk To Coastal Airfield Stormwater Systems, Jedidiah R. Langlois

Theses and Dissertations

Climate change is resulting in rising sea levels and increased rainfall, posing new challenges to stormwater management, particularly along coastlines. The airfield stormwater systems of Tyndall Air Force Base discharge directly into an interior bay of the Gulf of Mexico through tidal canals and ditches, creating a risk of system inundation from high tidewater conditions from sea-level rise (SLR). This study explores the performance and consequences of an inundated stormwater system from SLR during rainfall events using the EPA’s Stormwater Management Model (SWMM). One hundred and fifty-three combinations of SLR and return year storms were applied to a model of …


Persistence And Mitigation Of Pfas Within Concrete Stormwater Drainage Infrastructure, Jason R. Mcdonald Mar 2022

Persistence And Mitigation Of Pfas Within Concrete Stormwater Drainage Infrastructure, Jason R. Mcdonald

Theses and Dissertations

The persistence, fate, and transport of per- and poly-fluoroalkyl substances, which have been shown to have adverse effects on human health, have been previously studied in environmental media such as soils and groundwater. This study investigates concrete, a medium that is rarely studied but frequently present in instances where PFAS originating from AFFF releases and spills have occurred. Used heavily throughout aviation firefighting, AFFF poses environmental hazards due to the length of PFAS degradation and toxicological implications, thus its classification as a forever chemical. From the very limited reports to date, studies have suggested very slow release from concrete, potentially …


The Application Of Virtual Reality In Firefighting Training, Dylan A. Gagnon Mar 2022

The Application Of Virtual Reality In Firefighting Training, Dylan A. Gagnon

Theses and Dissertations

Immersive simulations such as virtual reality is becoming more prevalent for use in training environments for many professions. United States Air Force firefighters may benefit from incorporating VR technology into their training program to increase organizational commitment, job satisfaction, self-efficacy, and job performance. With implementing a new training platform, it is also important to understand the relationship between these variables and the perceived benefits and efficacy of the VR training, which has not yet been studied in previous research. This study addresses this issue by gathering data from fire departments currently fielding a VR fire training platform.


Application Of Machine Learning Models With Numerical Simulations Of An Experimental Microwave Induced Plasma Gasification Reactor, Owen D. Sedej Mar 2022

Application Of Machine Learning Models With Numerical Simulations Of An Experimental Microwave Induced Plasma Gasification Reactor, Owen D. Sedej

Theses and Dissertations

This thesis aims to contribute to the future development of this technology by providing an in-depth literature review of how this technology physically operates and can be numerically modeled. Additionally, this thesis reviews literature of machine learning models that have been applied to gasification to make accurate predictions regarding the system. Finally, this thesis provides a framework of how to numerically model an experimental plasma gasification reactor in order to inform a variety of machine learning models.


Burn Probability And Climate Change: A Quantitative Evaluation Of The Temporal Alterations Of Wildfire, David N. Robinson Mar 2022

Burn Probability And Climate Change: A Quantitative Evaluation Of The Temporal Alterations Of Wildfire, David N. Robinson

Theses and Dissertations

The intensity of extreme weather events, specifically wildfires, along the West Coast has slowly grown overtime due to atmospheric changes caused by climate change. The Air Force, though aware of the threat that is wildfire, does not currently have a quantitative way to assess the hazard to base locations. In this paper, burn probability is quantitatively calculated through the geospatial analysis programs to provide a means of assessing wildfire vulnerability. The FlamMap fire simulator generated burn probabilities for Vandenberg Air Force Base using climate data generated by the remote automated weather station on the base to highlight how the burn …


Improving Airfield Pavement Degradation Prediction Skill With Local Climate And Traffic, Evan M. Fortney Mar 2021

Improving Airfield Pavement Degradation Prediction Skill With Local Climate And Traffic, Evan M. Fortney

Theses and Dissertations

Airfield pavements are a critical component of the global transportation network that provide a platform for national defense. Preventative and corrective maintenance activities are founded upon accurate expectations of degradation. The leading pavement management software creates degradation predictions from pavement groups using age as the IV and current state conditions as the DV. For this work, a framework is created and implemented that utilizes a PCR model to build upon accepted practices for degradation modeling to enhance and possibly augment future prediction capabilities. The model was applied to pairs of location and pavement family and reveals several findings: the selected …


Climate-Informed Prediction And Forecast Modeling Of Installation Total Energy Consumption, Scott C. Weiss Mar 2021

Climate-Informed Prediction And Forecast Modeling Of Installation Total Energy Consumption, Scott C. Weiss

Theses and Dissertations

Climate variability is an external and stochastic factor that causes energy demand uncertainty. Energy managers can use climate-based models to understand future trends of energy demand and to adjust operations, policy, and budgets accordingly. This research focuses on 1) identifying how climate attributes impact energy use, 2) creating a historically informed statistical modeling framework to skillfully predict energy use, and 3) forecasting future changes to energy use and costs, using CMIP5 temperature projections, at the campus level. After synthesizing the existing breadth of research on climate-informed energy modeling, a skillful, unbiased, climate-informed total energy consumption prediction model is developed for …


Evaluation Of Efficient Water Reuse Technologies For Sustainable Forward Operating Bases, Kelsie L. Crouch Mar 2021

Evaluation Of Efficient Water Reuse Technologies For Sustainable Forward Operating Bases, Kelsie L. Crouch

Theses and Dissertations

A secure water source is essential to the resiliency and readiness of military installations and contingency operation locations, especially those located in the dry climates the US military operates in today. There are multiple issues of concern when identifying water sources, such as security, cleanliness, accessibility, and sustainability. Water resources pose a potential vulnerability to mission readiness in a remote, agile environment, such as a forward operating base (FOB). Having a secure water resource helps facilitate mission readiness in the contingency environment, offering the opportunity to be more resilient and cost-effective. Current water treatment technologies present the possibility to perform …


Conversion From Coal To Natural Gas At Wright Patterson Air Force Base: An Analysis And Case Study, Tyler A. Ferry Mar 2021

Conversion From Coal To Natural Gas At Wright Patterson Air Force Base: An Analysis And Case Study, Tyler A. Ferry

Theses and Dissertations

Over the last 20 years, natural gas has replaced coal as the preferred fossil fuel for heat and power generation across the United States, due to its increased prevalence, lower cost, and reduced environmental impacts. While most conversion decisions are driven by cost savings, proponents of energy transitions often cite emissions reductions as a tangential benefit. Over the same time, climate change and its impact on the environment and society have come to the forefront of scientific inquiry. One example of the transition from coal to natural gas can be found in Dayton, Ohio. Wright Patterson Air Force Base (WPAFB) …


Fluid Dynamics Modeling For Per- And Polyfluoroalkyl Substances Removal In Legacy Fire Suppression Systems, Jacob G. Spaulding Mar 2021

Fluid Dynamics Modeling For Per- And Polyfluoroalkyl Substances Removal In Legacy Fire Suppression Systems, Jacob G. Spaulding

Theses and Dissertations

Legacy per- and polyfluoroalkyl substances (PFASs) exist in the form of aqueous film-forming foams within hangar fire suppression systems throughout the country, posing a threat to both surrounding environments as well as local populations. The United States (US) Department of Defense (DoD), in conjunction with the US Environmental Protection Agency (EPA), is investigating best practices to flush out existing contaminants prior to disposal and replacement with a less environmentally harmful replacement. While current procedures dictate a triple rinse of the entire system to yield contaminant levels acceptable to the DoD, the practice has never truly been tested. Designed as a …


An Analysis Of Tinker Air Force Base Thermal Spray Hazardous Waste Stream From 2003-2019 And Its Potential Reclamation, Amy E. Silverbush Mar 2020

An Analysis Of Tinker Air Force Base Thermal Spray Hazardous Waste Stream From 2003-2019 And Its Potential Reclamation, Amy E. Silverbush

Theses and Dissertations

The disposal of hazardous waste threatens the environment and human health. However, certain hazardous wastes can be recycled or reclaimed to alleviate environmental and financial impacts associated with its disposal and resource demand reduction. A hazardous powder produced by the United States Air Force stems from aircraft maintenance and is composed of metals and ceramics, called thermal spray. This waste can be purchased by an industrial recycler if the waste is composed of valuable metals. Historic data from the depot-level maintenance base Tinker Air Force Base initiated an analysis of annual thermal spray hazardous waste disposal fees, which combined with …


Statistical Viability Analysis Of United States Air Force Estimating Cost Factor For Sustainable Construction, Philip A. Ramsey, Diedrich Prigge, Torrey J. Wagner, Alfred E. Thal Jr. May 2019

Statistical Viability Analysis Of United States Air Force Estimating Cost Factor For Sustainable Construction, Philip A. Ramsey, Diedrich Prigge, Torrey J. Wagner, Alfred E. Thal Jr.

Faculty Publications

Varying legislation and executive orders coupled with needs for energy resiliency have led the United States Air Force (USAF) to pursue sustainable construction. However, the limited understanding of initial costs to implement these changes have contributed to poor project cost estimating, resulting in 62 percent of USAF projects experiencing more than 5 percent cost growth. After reviewing 1628 USAF Military Construction (MILCON) construction projects in 922 category codes (CATCODEs), a twotailed t-test for populations with unequal variance was accomplished on the final normalized contract cost for 340 projects in 16 CATCODEs executed between 2002 and 2017. This analysis provides a …


Using Wind And Hydro Power To Sustain The Off-Grid Power Supply For A 50' Cruising Sailboat, Keisha Meyer, Torrey J. Wagner, Jada Williams May 2019

Using Wind And Hydro Power To Sustain The Off-Grid Power Supply For A 50' Cruising Sailboat, Keisha Meyer, Torrey J. Wagner, Jada Williams

Faculty Publications

Cruising sailboats operate with a power requirement modest enough to operate mostly or completely on renewable energy technology sources. Cruisers without renewable energy systems use the vessel’s diesel engine to charge the boat’s batteries; if the systems are operated at anchor, this dramatically decreases the time before the engine needs major overhaul. System users estimate a diesel engine can run approximately 8,000 hours underway before needing major overhaul, whereas operating 500 hours at anchor produces similar wear and tear on engine pistons. Although renewable energy systems have a high initial capital cost, these systems can provide the vessel’s electrical system …


Austere Location Wind Turbine Energy System Analysis, Lukas Cowen, Douglas S. Dudis, Torrey J. Wagner Apr 2019

Austere Location Wind Turbine Energy System Analysis, Lukas Cowen, Douglas S. Dudis, Torrey J. Wagner

Faculty Publications

One promising technology to combat an energy shortage in austere locations is wind energy. In combination with battery storage and generator backup, we explore the feasibility of using a hybrid energy system to reduce the volume of diesel fuel required. Modeling the energy demands in austere locations will enable missions in remote settings to optimize their energy costs, increased their energy resiliency and assure their supply. For a modeled time-series energy requirement that varied between 2.4 MW and 5.1 MW, the optimal wind system size was 9.9 MW of installed wind power paired with a 741 kWh battery. Assuming an …


Quantifying Permafrost Extent, Condition, And Degradation Rates At Department Of Defense Installations In The Arctic, Christopher A.J. Edlund Mar 2018

Quantifying Permafrost Extent, Condition, And Degradation Rates At Department Of Defense Installations In The Arctic, Christopher A.J. Edlund

Theses and Dissertations

The DoD is planning over $500M in military construction on Eielson Air Force Base (AFB) within the next three years. This construction program will expand the footprint of facilities and change parts of the storm water management scheme, which may have second order effects on the underlying permafrost layer. These changes in permafrost will drive engineering decision making at local and regional levels, and help shape the overall strategy for military readiness in the Arctic. Little site-specific knowledge exists on the human caused effects to permafrost at this location. In 2016, the permafrost degradation rates at Eielson AFB were modeled …


The Impacts Of Climate Change And Anthropogenic Processes On Permafrost Soils And Usaf Infrastructure Within Northern Tier Bases, Alexander J. Graboski Mar 2017

The Impacts Of Climate Change And Anthropogenic Processes On Permafrost Soils And Usaf Infrastructure Within Northern Tier Bases, Alexander J. Graboski

Theses and Dissertations

The Department of Defense is planning over $552M in military construction on Eielson Air Force Base within the next three fiscal years. Although many studies have been conducted on permafrost and climate change, the future of our climate as well as any impacts on permafrost soils, remains unclear. This research focused on future climate predictions to determine likely scenarios for the United States Air Force’s Strategic Planners to consider. The most recent 2013 International Panel on Climate Change report predicts a 2.2ºC to 7.8ºC temperature rise in Arctic regions by the end of the 21st Century in the Representative Concentration …


Adsorption Of Perfluorinated Compounds From Post-Emergency Response Wastewater, Christopher T. Schmidt Mar 2017

Adsorption Of Perfluorinated Compounds From Post-Emergency Response Wastewater, Christopher T. Schmidt

Theses and Dissertations

This research investigated the efficacy of granular activated carbon (GAC) as a method to treat water impacted with aqueous film forming foam (AFFF) after a firefighting response. Bench-top experiments were conducted and compared to field scale adsorber performance removing mg/L concentrations of PFAS in water contaminated with Military Specification AFFF. Batch tests compared four adsorbents, and determined Calgon F600 GAC and Rembind Plus mixed carbon media had the greatest perfluorooctane sulfonate (PFOS) capacities. Additional batch isotherm experiments using AFFF and higher PFOS concentrations (mg/L) indicated larger amounts of GAC are required (>30mg/L) for effective removal. Full-scale testing simulated an …


Nitrogen Rate And Landscape Impacts On Life Cycle Energy Use And Emissions From Switchgrass-Derived Ethanol, Eric G. Mbonimpa, Sandeep Kumar, Vance N. Owens, Rajesh Chintala, Heidi L. Sieverding, James J. Stone Jul 2016

Nitrogen Rate And Landscape Impacts On Life Cycle Energy Use And Emissions From Switchgrass-Derived Ethanol, Eric G. Mbonimpa, Sandeep Kumar, Vance N. Owens, Rajesh Chintala, Heidi L. Sieverding, James J. Stone

Faculty Publications

Switchgrass-derived ethanol has been proposed as an alternative to fossil fuels to improve sustainability of the US energy sector. In this study, life cycle analysis (LCA) was used to estimate the environmental benefits of this fuel. To better define the LCA environmental impacts associated with fertilization rates and farm-landscape topography, results from a controlled experiment were analyzed. Data from switchgrass plots planted in 2008, consistently managed with three nitrogen rates (0, 56, and 112 kg N ha−1), two landscape positions (shoulder and footslope), and harvested annually (starting in 2009, the year after planting) through 2014 were used as input into …