APPENDIX D

Carbon-Removal Pathways Technical Tool Overview

Deployment Instructions

The Carbon-Removal Pathways Technical Tool is provided as a downloadable file, which is only accessible through a Microsoft 365 business license. The application will not work with a personal Microsoft account. Following are the deployment instructions for the Airport Administrator to follow to access the tool. The same instructions and a video tutorial can be found with the technical tool package, which is available on the National Academies Press website (nap.nationalacademies.org) by searching for ACRP Research Report 270: Carbon Removal at Airports and then reviewing “Resources at a Glance.”

Step 1: Open the PowerApps Environment

Go to https://make.powerapps.com and select an environment in which to save the application.

Step 2: Select Apps

Click on the “Apps” menu item at the left-hand side of the screen to pull up a full list of applications.

Step 3: Select Import Canvas App

Click on “Import canvas app” from the top menu, then click the “Upload” button to upload the zipped package located with these instructions.

Step 4: Review Details and Click Import

Review package details and make sure “Create as new” shows up under “Import Setup” field. Then click the “Import” button.

Items to note

• Because of the complexity and large amount of data within the application, it will take several minutes to install. Please do not exit during installation.
• Once the application is installed, there will be an option to share with all users or to open the application.
  • All users may be selected to make the application available to all users on your tenant.
  • Clicking on “Open the application” will take users into edit mode to edit the application. This is not needed or recommended.
  • You do not need to do either.
• If you navigate back to the Apps menu, you will see that the application is now installed on your tenant. Do not forget to publish it.

For more information on how to share applications within an organization, visit Share a Canvas App with Your Organization on the Microsoft Learn website.

Land-Cover Type, Uses, and Conservation Practices

Not all land-cover types can be redeveloped to another land-cover type and provide CDR benefits.

Bare rock/sand/clay—May also be referred to as barren land. In general, only 15 percent of the land is covered with vegetation. These areas may be characterized by bedrock, desert pavement, volcanic material, sand dunes, strip mines, gravel pits, and others (Multi-Resolution Land Characteristics Consortium, n.d.).

Developed, high intensity—Areas with significant residency or offices and workspaces. These areas are generally from 80 to 100 percent covered by impervious surfaces (e.g., roads, rooftops, sidewalks) and may include apartment, commercial, and industrial buildings (Multi-Resolution Land Characteristics Consortium, n.d.).

Developed, low intensity—These areas have a combination of constructed materials and vegetation and frequently include single-family homes. Developed, low-intensity spaces are generally from 20 to 49 percent covered by impervious surfaces (Multi-Resolution Land Characteristics Consortium, n.d.).

Developed, medium intensity—These areas are similar to the low-intensity areas, having a mixture of constructed materials and vegetation. They are a bit more developed with impervious surfaces covering from 50 to 79 percent of the area (Multi-Resolution Land Characteristics Consortium, n.d.).

Developed open space—Areas with limited constructed materials that are mostly covered in lawn grass vegetation. Less than 20 percent of the area is covered by impervious surfaces. Examples include large-lot single-family homes, golf courses, recreational areas (e.g., parks), or spaces with vegetation planted for erosion control or aesthetics. Conservation practices include the following (Multi-Resolution Land Characteristics Consortium, n.d.):

• Improve turf or nonwoody vegetation cover
• Replace a strip of turf or nonwoody vegetation near watercourses or water bodies with woody plants

Grasslands/herbaceous—These areas are covered with graminoids (plants with a grass-like morphology) or herbaceous plants. Typically, over 80% of the area is covered with this vegetation type. Grassland and herbaceous land cover can be used for grazing but should not be tilled or intensively managed (Multi-Resolution Land Characteristics Consortium n.d.). Conservation practices include the following:

• Access control
• Brush management
• Fencing
• Forage harvest management
• Grade-stabilization structure
• Heavy-use protection area
• Nutrient management
• Pasture and hay planting
• Pest management
• Prescribed burning
• Prescribed grazing
• Riparian forest buffer
• Water well
• Watering facility
• Wildlife habitat management (uplands or wetlands)
• Windbreak/shelterbelt establishment

For more information, visit the USDA Natural Resources Conservation Service website.

Cultivated crops—These are areas that produce annual crops (e.g., soybeans, corn, vegetables) and perennial wood crops (e.g., fruit trees and vineyards) and are actively tilled. Crop production will account for more than 20 percent of the total vegetation in the area (Multi-Resolution Land Characteristics Consortium, n.d.). Conservation practices include the following (Food and Agriculture Organization of the United Nations, n.d.):

• No tillage to reduce soil disturbance
• Permanent organic soil cover by covering at least 30 percent of the area with crop residues or cover crops
• Species diversification of at least three different crop species

Deciduous forest—Areas with trees that are more than 5 m in height and cover more than 20 percent of total vegetation cover. More than 75 percent of the tree species drop their leaves each year when the seasons change (Multi-Resolution Land Characteristics Consortium, n.d.).

Evergreen forest—Areas with trees that are more than 5 m in height and cover more than 20 percent of total vegetation cover. More than 75 percent of the tree species keep their leaves throughout the year, and the canopy always has green foliage (Multi-Resolution Land Characteristics Consortium, n.d.).

Mixed forest—Areas with trees more than 5 m in height that cover more than 20 percent of total vegetation cover. Neither deciduous nor evergreen species are dominant over 75 percent of total tree cover (Multi-Resolution Land Characteristics Consortium, n.d.).

Pasture and hay—Areas with grasses, legumes, or a combination of the two. These vegetation types are planted for livestock grazing or to produce seed or hay crops. The pasture and hay must cover more than 20 percent of total vegetation in the area (Multi-Resolution Land Characteristics Consortium, n.d.). Conservation practices include the following:

• Improve turf or nonwoody vegetation cover
• Replace a strip of turf or nonwoody vegetation near watercourses or water bodies with woody plants

Open water—Less than 25 percent of the area is covered by any vegetation or soil (Multi-Resolution Land Characteristics Consortium, n.d.).

Perennial ice/snow—Areas that have a perennial cover of ice and snow that covers more than 25 percent of the land (Multi-Resolution Land Characteristics Consortium, n.d.).

Assumptions and Key Data Sources

Assumptions

Below are the key assumptions and formulas for the technical tool:

• Consistent removal potential throughout the lifetime of the project or pathway, fluctuations, and saturation points are not factored in for land-use pathways.
• No GHG emissions are being emitted throughout the project.
• Afforestation selects only a few of the land-cover types.
• The electricity and natural gas costs were provided by the National Renewable Energy Laboratory.
• Low costs are assumed to zero as some land-use practices to not require additional costs or allow for incentives that alleviate the costs.
• DAC cost assumptions include the following:
  • DAC costs in the tool are based on specific data calculations developed by NREL for this project. The following formula includes the thermal energy input, electrical energy input,

• • cost of thermal energy, cost of electricity, cost of operations and maintenance, cost of capital per t-CO₂/year, capital recovery factor, plant utilization (0.9), and Chemical Engineering Cost Plant Cost Index.
  • Formula to calculate DAC costs:
    • (gas input * gas price) + [(electricity input * electricity price)/1000] + O&M costs + [capital costs * (DRF/utilization)]
    • $LCOD=E_{th}•C_{th}+E_{el}•C_{el}+\left(C_{O\&M}+C_{Capital}•\frac{CRF}{U}\right)•\left(\frac{CEPC{I}_{old}}{CEPC{I}_{2021}}\right)$
• Costs for all other pathways are based on additional research and best professional judgment for assigning cost ranges in the tool.
• Acreages are approximates based on the NLCD 2019 Land Cover (CONUS) Multi-Resolution Land Characteristics Consortium dataset. Details found in the tool are estimates to help make informed decisions. The results should not be used as exact quotes.
• Soil carbon calculations are not available for the State of Alaska.
• NPIAS airports that were not in the geofenced data sources are assumed to have similar soil carbon-removal opportunities as the closest airport identified geographically.

Key Data Sources

• COMET Planner Tool, COMET-Planner
• USA Airport Areas—Overview (arcgis.com)
• NPIAS airports, https://www.faa.gov/sites/faa.gov/files/2022-10/ARP-NPIAS-2023-Appendix-A.pdf
• National Land Cover Database 2019 and 2016
• United States Geological Survey coastlines
• NREL localized electricity and gas costs
• DAC costs, NREL (Appendix 3)
• NLCD 2019 Land Cover (CONUS) Multi-Resolution Land Characteristics Consortium

Cost and Carbon-Removal Potential Data Sources

The low- and high-cost ranges in the tool were provided by CSU and NREL. Supplemental cost and carbon-removal potential ranges from additional research in the guide are from the sources below.

Soil-Based

Bossio, D. A., S. C. Cook-Patton, P. W. Ellis, J. Fargione, J. Sanderman, P. Smith, S. Wood, R. J. Zomer, M. von Unger, I. M. Emmer, and B. W. Griscom. 2020. “The Role of Soil Carbon in Natural Climate Solutions.” Nature Sustainability, 3(5), pp. 391–98. https://doi.org/10.1038/s41893-020-0491-z.

Griscom, B. W., J. Adams, P. W. Ellis, R. A. Houghton, G. Lomax, D. A. Miteva, W. H. Schlesinger, D. Shoch, J. Siikamäki, P. Smith, P. Woodbury, C. Zganjar, A. Blackman, J. Campari, R. Conant, C. Delgado, P. Elias, T. Gopalakrishna, M. Hamsik, M. Herrero, J. Kiesecker, E. Landis, L. Laestadius, S. Leavitt, S. Minnemeyer, S. Polasky, P. Potapov, F. Putz, J. Sanderman, M. Silvius, E. Wollenberg, and J. Fargione. 2017. “Natural Climate Solutions.” Proceedings of the National Academy of Sciences, 114(44), pp. 11645–50. https://doi.org/10.1073/pnas.1710465114.

IPCC. 2019. Special Report on Climate Change and Land. https://www.ipcc.ch/srccl/.

NASEM. 2015. Climate Intervention: Carbon Dioxide Removal and Reliable Sequestration. National Academies Press, Washington, DC. https://doi.org/10.17226/18805.

Forests

Griscom, B. W., J. Adams, P. W. Ellis, R. A. Houghton, G. Lomax, D. A. Miteva, W. H. Schlesinger, D. Shoch, J. Siikamäki, P. Smith, P. Woodbury, C. Zganjar, A. Blackman, J. Campari, R. Conant, C. Delgado, P. Elias, T. Gopalakrishna, M. Hamsik, M. Herrero, J. Kiesecker, E. Landis, L. Laestadius, S. Leavitt, S. Minnemeyer, S. Polasky, P. Potapov, F. Putz, J. Sanderman, M. Silvius, E. Wollenberg, and J. Fargione. 2017. “Natural Climate Solutions.” Proceedings of the National Academy of Sciences, 114(44), pp. 11645–50. https://doi.org/10.1073/pnas.1710465114.

IPCC. 2019. “Special Report on Climate Change and Land.” 2019. https://www.ipcc.ch/srccl/.

National Academies of Sciences, Engineering, and Medicine. 2015. Practices to Develop Effective Stakeholder Relationships at Smaller Airports. Edited by B. Elliot, R. Chapman, and L. Kelly. Washington, DC: The National Academies Press. https://doi.org/10.17226/22114.

National Academies of Sciences, Engineering, and Medicine. 2019. Negative Emissions Technologies and Reliable Sequestration: A Research Agenda. Washington, DC: The National Academies Press. https://doi.org/10.17226/25259.

Smith, P. 2016. “Soil Carbon Sequestration and Biochar as Negative Emission Technologies.” Global Change Biology, 22(3), pp. 1315–24. https://doi.org/10.1111/gcb.13178.

Trabucco, A., R. J. Zomer, D. A. Bossio, O. van Straaten, and L. V. Verchot. 2008. “Climate Change Mitigation through Afforestation/Reforestation: A Global Analysis of Hydrologic Impacts.” Agriculture, Ecosystems and Environment, June. https://doi.org/10.1016/j.agee.2008.01.015.

DAC

Carbon Engineering. n.d. “Direct Air Capture of CO₂.” Accessed April 28, 2023. https://carbonengineering.com/.

Keith, D. W., G. Holmes, D. St. Angelo, and K. Heidel. 2018. “A Process for Capturing CO₂ from the Atmosphere.” Joule, 2(8), pp. 1573–94. https://doi.org/10.1016/j.joule.2018.05.006.

McQueen, N., K. Gomes, C. McCormick, K. Blumanthal, M. Pisciotta, and J. Wilcox. 2021. “A Review of Direct Air Capture (DAC): Scaling up Commercial Technologies and Innovating for the Future.” Progress in Energy, Vol. 3 (March). https://doi.org/10.1088/2516-1083/abf1ce.

BiCRS

IEA. 2020. CCUS in Clean Energy Transitions—Analysis. IEA. September 2020. https://www.iea.org/reports/ccus-in-clean-energy-transitions.

National Energy Technology Laboratory. 2017. Illinois Basin-Decatur Project. https://www.netl.doe.gov/sites/default/files/2018-11/Illinois-Basin-Decatur-Project.pdf.

Sandalow, D., R. Aines, J. Friedmann, C. McCormick, and D. L. Sanchez. 2021. Biomass Carbon Removal and Storage (BiRCS) Roadmap. LLNL-TR-815200. Lawrence Livermore National Lab, Livermore, CA. https://doi.org/10.2172/1763937.

Ocean-Based

Eisaman, M. D., J. L. B. Rivest, S. D. Karnitz, C. F. de Lannoy, A. Jose, R. W. DeVaul, and K. Hannun. 2018. “Indirect Ocean Capture of Atmospheric CO₂: Part II. Understanding the Cost of Negative Emissions.” International Journal of Greenhouse Gas Control, Vol. 70, pp. 254–61.

Markels, M., and R. T. Barber. 2002. “Sequestration of Carbon Dioxide by Ocean Fertilization.” In Environmental Challenges and Greenhouse Gas Control for Fossil Fuel Utilization in the 21st Century, edited by M. Mercedes Maroto-Valer, Chunshan Song, and Yee Soong, pp. 119–31. Boston, MA: Springer U.S. https://doi.org/10.1007/978-1-4615-0773-4_9.

National Academies of Sciences, Engineering, and Medicine. 2022. A Research Strategy for Ocean-Based Carbon Dioxide Removal and Sequestration. National Academies Press, Washington, DC. https://doi.org/10.17226/26278.

Primeau, F. 2005. “Characterizing Transport between the Surface Mixed Layer and the Ocean Interior with a Forward and Adjoint Global Ocean Transport Model.” Journal of Physical Oceanography, 35(4): 545–64. https://doi.org/10.1175/JPO2699.1.

Renforth, P. 2019. “The Negative Emission Potential of Alkaline Materials.” Nature Communications, 10(1): 1401. https://doi.org/10.1038/s41467-019-09475-5.

Biochar

Fawzy, S., A. I. Osman, H. Yang, J. Doran, and D. W. Rooney. 2021. “Industrial Biochar Systems for Atmospheric Carbon Removal: A Review.” Environmental Chemistry Letters, 19(4): 3023–55. https://doi.org/10.1007/s10311-021-01210-1.

Fuss, S., W. F. Lamb, M. W. Callaghan, J. Hilaire, F. Creutzig, T. Amann, T. Beringer, W. de Oliveira Garcia, J. Hartmann, T. Khanna, G. Luderer, G. Nemet, J. Rogelj, P. Smith, J. Vicente, J. Wilcox, M. del Mar Zamora Dominguez, and J. Minx. 2018. “Negative Emissions—Part 2: Costs, Potentials and Side Effects.” Environmental Research Letters, 13(6). https://doi.org/10.1088/1748-9326/aabf9f.

IPCC. 2019. Special Report on Climate Change and Land. 2019. https://www.ipcc.ch/srccl/.

Enhanced Mineralization

Curry, K. C. 2020. U.S. Geological Survey, Mineral Commodity Summaries: Iron and Steel Slag. USGS. https://pubs.usgs.gov/periodicals/mcs2020/mcs2020-iron-steel-slag.pdf.

Renforth, P. 2019. “The Negative Emission Potential of Alkaline Materials.” Nature Communications, 10(1): 1401. https://doi.org/10.1038/s41467-019-09475-5.

Sandalow, D., R. Aines, J. Friedmann, P. Kelemen, C. McCormick, I. Power, B. Schmidt, and S. Wilson. 2021. Carbon Mineralization Roadmap Draft October 2021. LLNL-CONF-827384. Lawrence Livermore National Lab, Livermore, CA. https://www.osti.gov/biblio/1829577.