At the national level, average carbon monoxide (CO) concentrations have decreased substantially over the years.   As of September 2010, all CO nonattainment areas have been redesignated to maintenance areas.  Federal requirements for modeling project-level “hot-spot” analyses create challenges for state DOTs and other agencies responsible for project implementation. These challenges may be partly addressed through programmatic agreements (PAs) based on new models and guidance.  PAs can help state DOTs avoid performing unnecessary CO analyses under NEPA.  

The research was divided into two phases. The first phase developed the draft Programmatic Agreement (PA) template and a draft Technical Support Document (TSD) template for project-level carbon monoxide (CO) hot-spot analysis.  Because CO analysis can be performed using a “worst case” approach, a broad range of project types and worst case modeling inputs were assessed.  The templates set a base that state DOTs can tailor for their own specific needs.

The second phase consisted of outlining potential research areas that would support NEPA analyses and help in developing PAs for Particulate Matter (PM) and Mobile Source Air Toxics (MSATs).

Project deliverables are as follows:

The agency's final research report with all appendices.

https://onlinepubs.trb.org/onlinepubs/nchrp/docs/NCHRP25-25(78)_FR.pdf

Appendix B, Programmatic Agreement Template, and Appendix C, Technical Support Document Template, in MS Word format to ease use as base documents.

https://onlinepubs.trb.org/onlinepubs/nchrp/docs/NCHRP25-25(78)_AppendixB.docx

https://onlinepubs.trb.org/onlinepubs/nchrp/docs/NCHRP25-25(78)_AppendixC.docx

The data files are also available for download and contain MOVES2010b input and output files used in developing the PA.  The inputs are in both excel file format and MySQL and reflect the speeds/grades discussed in the report. MOVES output files are in MySQL format only. Additionally, CAL3QHC input and output files are provided for the intersection configurations modeled for all four quadrants and urban/rural speed configurations examined during this study. Similar speed/grade and setting combinations are provided for arterials and freeways.      

https://onlinepubs.trb.org/onlinepubs/nchrp/docs/NCHRP25-25(78)_FinalModelFiles.zip