The U.S. Environmental Protection Agency (EPA) and the Iowa DNR are required by law to reduce exposure to hazardous air pollutants (HAPs) that threaten human or the environment. EPA has issued over 130 National Emission Standards for Hazardous Air Pollutants (NESHAP). Several of those NESHAP affect facilities in Iowa. DNR has developed implementation tools for some of 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 a facility-wide potential to emit of 10 tons per year or more of any single HAP or 25 tons per year or more of any combination of HAP. Area sources are those with a potential to emit below the major source thresholds.
Air Toxics Standards for Stationary Engines
(40 CFR Part 63 Subpart ZZZZ, also known as RICE NESHAP*)
The RICE NESHAP was first promulgated in 2004, and has been amended several times since then. This NESHAP places requirements on owners and operators of a wide variety of stationary engines. RICE NESHAP is the commonly-used acronym for the National Emission Standards for Hazardous Air Pollutants (NESHAP) for Stationary Reciprocating Internal Combustion Engines (RICE) [40 Code of Federal Regulations (CFR) Part 63, Subpart ZZZZ]
Compliance Assistance Tools
DNR has created several compliance assistance tools for facilities subject to the RICE NESHAP.
To obtain information on whether a specific engine may be subject to the RICE NESHAP or whether it is in compliance with RICE NESHAP requirements, please contact Sarah Mousel at the DNR (Sarah.Mousel@dnr.iowa.gov or call 515-725-8403).
EPA has developed the following RICE NESHAP implementation tools and guidance:
Notification Requirement for Installation of Control Equipment on Existing Engines
Control equipment may be installed on an existing stationary engine without modifying the engine's construction permit. This permitting exemption is allowed under 567 IAC 22.1(2) "g". Facilities choosing this option are required to submit a notification to DNR 30 days prior to installing the control equipment.
If the exhaust stack for the engine will be modified significantly, a construction permit may be necessary. If you have any questions about whether your engine qualifies for this permitting exemption, please call the Construction Permit Help Line (1-877-AIR-IOWA).
Note: Facilities that already submitted an initial notification for the Major Source Boiler MACT promulgated on March 21, 2011, are not required to submit another initial notification at this time. Facilities that have not submitted an initial notification since the “old” Boiler MACT (promulgated in 2004) will need to submit a new notification.
Area Source Boilers (6J)
The Area Source Boiler NESHAP does not apply to process heaters, and it does not apply to “gas-fired boilers,” as defined in 6J: Gas-fired boiler includes any boiler that burns gaseous fuels not combined with any solid fuels and burns liquid fuel only during periods of gas curtailment, gas supply interruption, startups, or periodic testing on liquid fuel. Periodic testing of liquid fuel shall not exceed a combined total of 48 hours during any calendar year.
To help facilities understand new requirements to reduce air emissions from Metal Fabrication and Finishing operations, the Iowa DNR Air Quality Bureau and the Iowa Air Emissions Assistance Program (IAEAP) at the University of Northern Iowa have developed important compliance assistance tools. These tools will help you determine if you are subject to the new rule (6X NESHAP), and how to comply with the requirements.
Existing facilities that are subject to the 6X NESHAP will need to comply with these new standards by July 25, 2011. To access the short and informative 6X NESHAP tutorials and other information, go to:
For questions about the applicability of the 6X NESHAP to your facility, please call the Iowa DNR’s toll free air quality help line at 1-877-AIR-IOWA(1-877-247-4692).
Small businesses (those with 100 or fewer Iowa employees) can also obtain free, confidential regulatory assistance from the IAEAP. You may also contact IAEAP by phone at 319-273-8905.
Dry cleaning facilities that use perchloroethylene (also known as perc or PCE) are subject to the National Emission Standards for Hazardous Air Pollutants (NESHAP). This rule includes requirements for control equipment, leak inspections and repair, and record keeping and reporting.
Questions about Dry Cleaner NESHAP requirements may be directed to Sarah Mousel at DNR or call 515-418-7304.
Small businesses (those with 100 or fewer Iowa employees) can also obtain free, confidential regulatory assistance from the Iowa Air Emissions Assistance Program (IAEAP).
In September 2014, the Iowa DNR adopted the federal standard for the National Emission Standards for Hazardous Air Pollutants for Prepared Feeds Manufacturing at Area Sources (40 CFR 63 Subpart DDDDDDD), otherwise known as the 7D Rule or 7D NESHAP.
The 7D NESHAP applies to a facility that manufactures prepared animal feed or additives for animal feed (sometimes known as a "feed mill"). Affected facilities must comply with specific requirements to minimize dust and emissions from storage, use, or handling of materials containing chromium and manganese.
The Iowa DNR and the Iowa Air Emissions Assistance Program (IAEAP) at the University of Northern Iowa are assisting affected facilities with the 7D NESHAP and related air construction permitting requirements. For questions or to receive compliance assistance, see the resources provided below.
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 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.
