This site was created to help project sponsors determine if their project parameters fall within the acceptable range of modeled parameters to rely on the CO categorical hot-spot finding. FHWA modeled a large intersection (described below) to determine the resulting maximum CO concentrations for the project. Project sponsors may be able to rely on the CO categorical hot-spot finding in place of doing their own CO hot-spot analysis as part of a project level conformity determination in CO maintenance areas if the project's parameters fall within the acceptable range of the finding's modeled parameters. Reliance on the CO categorical hot-spot finding is still subject to existing interagency consultation and the public involvement requirements under NEPA and the conformity rule (40 CFR 93.105) for the individual project.
FHWA's CO Categorical Hot-Spot Memo and Finding can be found on the main FHWA CO Categorical Hot-Spot page includes a full discussion regarding use of the CO categorical hot-spot finding. Further supporting material (FHWA's CO Categorical Hot-Spot Finding Technical Document and model inputs/outputs) can also be found at the same location. Note: This finding only applies in urban areas and in States other than California.
Summary of urban intersection analyzed:
Urban Intersection - Go to Project Form >>