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Transportation Conformity Reference Guide

Exhibit 42 Text

  1. Project/Intersection Description
  2. Determine air quality/regulatory objectives
  3. Assemble all data pertaining to intersection-related traffic conditions
  4. Multiple intersection screening/ranking
  5. Rank Top 20 by traffic volumes
  6. Calculate LOS for Top 20
  7. Rank by LOS
  8. LOS=A, B, C
  9. LOS=D, E, F
  10. No further analysis required unless in Top 3 based on traffic volumes
  11. Model Top 3 based on LOS
  12. Model Top 3 based on traffic volumes
  13. Individual intersection modeling
  14. Assemble data on traffic, meteorology, site characteristics, background
  15. Locate receptors
  16. Compute 1-hour peak-traffic concentrations using CAL3QHC
  17. Apply persistence factor and background
  18. Compare results with NAAQS

The flows are as follows:

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Updated: 07/06/2011
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