All four materials—agricultural residues, corn grain, wastewater treatment sludge, and wood mill waste—can serve as feedstocks for producing Sustainable Aviation Fuel (SAF) due to their organic nature and potential for biomass conversion processes. Agricultural residues and wood mill waste can be thermochemically converted, while corn grain can be fermented to produce biofuels. Additionally, wastewater treatment sludge is rich in organic matter, which can be processed through anaerobic digestion or other technologies to yield biofuels, all contributing to a circular economy by reducing waste and lowering carbon emissions in aviation fuel production.