Recently, bio-mediated and bio-inspired solutions in the field of geotechnical engineering havebeen proposed as sustainable alternatives to traditional, cement-intensive business-as-usual technologies for infrastructure resiliency through geologic hazard mitigation. As these biogeotechnologies develop, it is imperative that quantitative sustainability assessment, such as life cycle sustainability assessment (LCSA), is employed to assess and guide their sustainable development. This can ensure that they produce both technological and sustainability advantages compared to traditional technologies considering social, environmental, and economic impacts. This dissertation addresses these needs for improved environmental assessment across biogeotechnologies by presenting a framework to evaluate the environmental impacts and cost across the whole life cycle of a geologic hazard mitigation project.

Chapter 1 introduces bio-mediated and bio-inspired geologic hazard mitigation techniques aspotentially sustainable alternatives to existing technologies and life cycle sustainability assessment (LCSA) as a method to evaluate them. Chapter 2 then presents a systematic literature review of emerging bio-mediated and bio-inspired ground improvement LCSA studies, including those focused on enzyme induced carbonate precipitation (EICP), microbially induced carbonate precipitation (MICP) and microbially induced desaturation and precipitation (MIDP). The review demonstrates that environmental impacts such as global warming and eutrophication are the most assessed and that inconsistencies in methodology limit the application of the reviewed assessments.

Chapter 3 of this dissertation presents a framework for the evaluation of the environmentalimpacts and costs incurred across the whole life cycle of geotechnical earthquake mitigation projects. This chapter also provides clear guidance for completion of a whole life cycle assessment following the ISO 14040 and 14044 life cycle assessment standards. Permeation grouting is evaluated as a liquefaction mitigation technique to provide an example implementation of the proposed framework and guidance. This case study shows that the construction stage of the permeation grouting project, specifically raw material supply for the microfine cement grout, contributes greatly to the whole life cycle impacts. Site investigation activities account for less than 1% of whole life cycle impacts suggesting that an increased scope site investigation program could provide a better understanding of the subsurface, reducing design uncertainties, without significantly impacting project sustainability.

Finally, a life cycle assessment of EICP columns for ground improvement is completed inChapter 4 to determine the environmental sustainability of EICP columns as compared to permeation grouting. The study finds that EICP columns impacts are primarily due to calcium chloride and urea production and transportation, with EICP biogeochemical process emissions (i.e., ammonium production) accounting for the high eutrophication potential of EICP columns. Other than when considering eutrophication potential, EICP columns present as a more environmentally sustainable alternative to cement-based ground improvement.

California’s freight transportation system is a vital part of the state’s economy but is a significant contributor to greenhouse gas emissions and generates an even higher portion of regional and local air pollution. The state’s primary strategy for reducing emissions from the on-road freight sector relies on deploying new vehicle and fuel technologies, such as electric medium- and heavy-duty vehicles. The market for electric truck technologies is developing rapidly.

The goal of this research is to quantify the life cycle environmental impacts and life cycle costs for on-road goods movement in California to estimate the abatement potential and economic costs and benefits of electrifying California’s freight truck sector. The study compares the emissions and costs of urban conventional gasoline and diesel Class 3–8 vehicles with electric heavy-duty vehicles (i.e., electric trucks) for a range of freight and commercial vocations. A model of freight vehicle operations is developed based on representative vehicle location data, and linked with life cycle emissions inventory, technology cost, and pollution health damage cost data. The model is then used to assess energy and capacity requirements for electric trucks and battery systems and explore the impacts of a range of charging strategies and vehicle duty cycles (i.e., vocations) on energy, costs, and emissions between 2020 and 2040.

Where emissions occur, and how emissions of different pollutants are affected by factors including vocation, duty cycle, powertrain configuration, and fuel pathway, will influence the effectiveness and economic costs of emissions reduction strategies. On a per mile basis, replacing a conventional gasoline or diesel truck can reduce CO₂-equivalent (CO₂e) emissions by 50%–75% compared to conventional gas and diesel vehicles. Statewide, 100% electrification of in-state Class 8 vehicles by 2040 could reduce annual CO₂e emissions by nearly than 30% (50 million metric tonnes per year), and electrification of Class 3 trucks statewide would likely half current PM2.5 emissions from transportation. The costs of emissions abatement from truck electrification ranged from $0.25 to $182 per metric tonne of CO₂e for trucks deployed in 2020, but these costs are likely to fall dramatically by 2040. Full electrification of the in-state registered Class 3–8 vehicle fleet by 2040 would significantly reduce criteria pollutants and aerosols emissions; this in turn could reduce pollution related damages in the state by $507 million per year by 2025, and by some $1.6 billion by 2040.

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The offshore wind industry is constantly evolving, and this evolution is not limited to wind turbines, but extends to the production, installation, operation, maintenance, and decommissioning phases of offshore wind farm life cycles. To better understand how this evolving technology has been assessed in research, this study undertakes a systematic review of published life cycle assessment of offshore wind. The review interrogates how the life cycle phases of offshore wind farms are represented and modeled in LCA and identifies gaps between current practice in LCA and the latest technology used in the industry. Additionally, a review of siting parameters (e.g., geographic location and distance to shore), reference sources, phase assumptions, and impact categories evaluated is presented. The obtained results show the need for updated models that better reflect the industry's current practices and to conduct studies for developing markets where offshore wind has potential for growth, but comprise a small number of the previous studies conducted.

Electric vehicle adoption is increasing rapidly in the United States, driven by policies aimed at mitigating climate change. Lithium-ion batteries are the key enabling technology for EVs. The production and refining of lithium is thus essential to electric vehicle manufacturing. Lithium is considered a critical mineral in the United States because its use is linked to national security, energy and transportation needs and its ease of availability in the future is not guaranteed. Understanding how much lithium is required for a clean transportation future is important to mitigate risks associated with lithium depletion and potential barriers to achieving climate mitigation targets. For this reason, the following thesis models lithium demand and recycling in the United States from 2020 to 2050 under a variety of scenarios that examine vehicle battery size, vehicle ownership rates, and recycling rates to determine the quantity of virgin lithium required for complete electrification of the on-road US fleet by 2050. The model shows that with no significant changes in battery size or mode share US lithium demand will be 300 million kg in 2050 exceeding current global lithium production by 200% and recycled material will not be able to close the gap between future demand and current production. Reducing only battery size can result in up to a 29% decrease in lithium demand while shifting mode shares only can result in a 67% decrease in lithium demand in 2050.

The dramatic increase in electric vehicle (EV) sales has led to a rapid increase in deployed lithium-ion battery (LIB) capacity over the last decade. As EV batteries age and are retired from use in vehicles, they will require management. Second-life applications are often proposed as an environmentally and economically preferable management strategy to direct recycling or disposal. In particular, the repurposing of EV LIBs in stationary applications is expected to provide cost-effective solutions for utility-scale energy storage applications. However, the adoption of second-life battery energy storage systems (BESS) has been slow. One barrier to adoption is the lack of meaningful cost estimates of second-life BESS. Thus, this study develops a model for estimating the Levelized Cost of Storage (LCOS) for second-life BESS and develops a harmonized approach to compare second-life BESS and new BESS. This harmonized LCOS methodology predicts second-life BESS costs at 234-278 ($/MWh) for a 15-year project period, costlier than the harmonized results for a new BESS at 211 ($/MWh). Despite having a higher LCOS, the upfront costs for second-life BESS are 64.3-78.9% of new systems' costs. Results for second-life BESS are highly sensitive to assumptions of discount rate, depth of discharge, and module repurposing costs. If deemed environmentally or societally beneficial, policies should stimulate the use of second-life LIBs, such as providing incentives equal to or greater than those available for first life BESS. Further work can explore comparative economics at smaller scales and quantify non-economic benefits of second-life BESS.

Electric vehicles (EVs) are a critical element of strategies for decreasing global greenhouse gas emissions. EVs are powered by lithium-ion batteries, which are material-intensive and require mining and processing that result in environmental and social impacts. Several governments, including the European Union, the state of California, and the Republic of China, have recognized that reusing, repurposing, and then recycling the battery at its end-of-life, also known as the waste hierarchy, is necessary to mitigate the externalities of the transition to EVs. Policy focused on the lithium-ion battery end-of-life have focused on recycling, and particularly on recovering cathode materials instead of the anodes and other materials, due to their comparably higher environmental, economic, and social impacts, as well as the geographical concentration of production. Prior studies have evaluated these impacts but have not considered the influence cathode chemistry and technological development may have on material circularity, resulting in a difference of material composition between batteries reaching their end-of-life and batteries currently being manufactured.

For policies intended to create a circular EV battery industry to be effective, the quantity of materials reaching their end-of-life, and the environmental and social tradeoffs between end-of-life solutions, must be determined. This research uses methods from industrial ecology, including material flow analysis and life cycle analysis, to address a gap in lithium-ion battery policy; in particular, the design and evaluation of policies that consider the rapid evolution of lithium-ion battery technologies which will result in decreased use of cobalt and an increase in energy density. Material flow analysis is used to calculate spatially and temporally resolved battery material flows and propose a method for calculating feasible recycled content standards, accounting for cathode chemistry mix, EV sales, and lifespan. Technoeconomic assessment is used to evaluate the cost of recycling, considering location, cathode chemistry, and transportation mode. Lastly, life cycle analysis is used to evaluate the material life cycle impacts of directly recycling high cobalt batteries in comparison to extending the lifespan through reuse.