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Air Toxics – NESHAP

The U.S. Environmental Protection Agency (EPA) and the Iowa DNR are required by law to reduce exposure to hazardous air pollutants (HAPs). EPA has issued over 120 National Emission Standards for Hazardous Air Pollutants (NESHAP). Approximately 50 of those NESHAP affect facilities in Iowa. DNR has developed implementation tools for the NESHAP in each section listed below.

Some NESHAP apply to both major and area sources of HAP, and some apply just to one or the other. Major sources are those with facility-wide potential or actual emissions of 10 tons per year or more of any single HAP or 25 tons per year or more of a combination of HAP. Area sources are those with potential and actual emissions below the major source thresholds.

Reciprocating Internal Combustion Engines (RICE) (major and area sources)
40 CFR Part 60, Subparts IIII and JJJJ, 40 CFR Part 63, Subpart ZZZZ

Boilers and Process Heaters (major and area sources)
40 CFR Part 63, Subpart DDDDD and Subpart JJJJJJ

Gasoline (area sources)
40 CFR Part 63, Subpart BBBBBB and Subpart CCCCCC

Metal Fabrication and Finishing (area sources)
40 CFR Part 63, Subpart XXXXXX

Perc Dry Cleaning Facilities (major and area sources)
40 CFR Part 63, Subpart M

Plating and Polishing (area sources)
40 CFR Part 63, Subpart WWWWWW

Prepared Feeds (area sources)
40 CFR Part 63, Subpart DDDDDDD

Surface Coating (Auto Body and Miscellaneous) (area sources)
40 CFR Part 63, Subpart HHHHHH

Small Unit Exemption (SUE) Eligibility

A facility owner or operator is not eligible to use the small unit exemption (SUE) (567 IAC subrule 22.1(2)”w”) if an emission unit emits a hazardous air pollutants and is “required to be reviewed for compliance” with a National Emission Standard for Hazardous Air Pollutants (NESHAP). This DNR guidance document helps explain this requirement, and includes several examples of equipment that can still use the SUE, and some equipment that may no longer qualify for the SUE because of NESHAP requirements.

Small Business Assistance

Small businesses can obtain help with the area source NESHAPS through the Iowa Air Emissions Assistance Program. More information regarding this program, including the eligibility requirements, can be found on the Small Business Assistance website.

Other NESHAP Regulations and Implementation Tools
  • EPA's NESHAP Page
  • EPA’s Area Source Page (look for the subpart or the rule name in the table)
  • Nebraska DEQ site (Click on “Focus on Air on the left-side menu, scroll down until you see the link for “Air Toxics Program,” then click on link for “Jump to Air Toxics Notebook.” You can then click on the links to search by federal subpart or by industry category. There is not a direct link to this page. Note that any information regarding Nebraska facilities or Nebraska’s state rules are not applicable to Iowa DNR or facilities in Iowa).