APEN and permit threshold table

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The following table lists APEN and permit threshold limits for pollutants in Colorado. VOCs and NOx are considered precursors to ozone and therefore businesses in the 8-hour ozone nonattainment area must report at the nonattainment thresholds for those pollutants. All other pollutants are reported at the attainment thresholds. The 8-hour ozone nonattainment area currently consists of the following counties:

  • Adams
  • Arapahoe
  • Boulder (including most of Rocky Mountain National Park)
  • Broomfield
  • Denver
  • Douglas
  • Jefferson
  • and a portion of Larimer and Weld (see ozone nonattainment map).  

Ozone nonattainment map 

APEN AND PERMIT REPORTING THRESHOLDS FOR ATTAINMENT AND NONATTAINMENT AREAS

 

APEN 

Permit 

Pollutant Category

           Attainment           (tons per year)

    Nonattainment    (tons per year)

         Attainment          (tons per year)

       Nonattainment       (tons per year)

Volatile organic compounds (VOCs)

2

1

5

2

PM-10 and PM-2.5

2

1

5

1

Total suspended particulates (TSP)

2

1

10

5

Carbon monoxide (CO)

2

1

10

5

Sulfur dioxide (SOx)

2

1

10

5

Nitrogen oxides (NOx)

2

1

10

5

Lead

100 pounds per year

100 pounds per year

200 pounds per year

200 pounds per year

Other criteria pollutants1

2

1

2

2

Hazardous Air Pollutants (HAPs)

 250 pounds per year 250 pounds per year _
1-Other criteria pollutants (fluorides, sulfuric acid mist, hydrogen sulfide, total reduced sulfur, reduced sulfur compounds, and municipal waste combustor emissions).