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November 2, 2026 NC State

Map of the United States showing county-level nitrogen oxides (NOₓ) emissions density in tons per year per square mile. Counties are shaded from light cream (lowest emissions) to dark blue (highest emissions). Higher emissions densities are concentrated around major metropolitan areas, transportation corridors, industrial regions, Gulf Coast counties, parts of California, the Northeast Corridor from Washington to Boston, and other urbanized areas. Lower emissions densities dominate much of the rural western and central United States.

The Science Behind Air Quality Standards Needs Expert Review

By frey On November 2, I provided public comments to the U.S. Environmental Protection Agency’s Clean Air Scientific Advisory Committee (CASAC) regarding EPA’s draft Integrated Science Assessment...