Stationary engines or generators

Air emissions

Stationary engines, commonly used as back-up or emergency generators, are regulated by several federal air standards and state air permits. Learn more on the MPCA air quality program page for engines.


Use this emissions calculator to determine if you need a permit for your gasoline, diesel, and natural gas engines: File Air emissions calculator: Internal Combustion Engines (p-sbap5-25)A permit is required if one of the federal performance standards applies to the engine or if potential air emissions from the entire business are over certain levels. The calculator also provides guidance on the federal standards.


The U.S. EPA has resources to help you comply with federal standards for engines, which includes NESHAP and NSPS. Use their engine regulation navigation tools for a quick assessment and summary of requirements for your engine.

Air permit due dates

Requirement Due date
Emission inventory fee for previous year Mailed to permit holders in March, due within 60 days
Emission inventory April 1
Corrections to emission inventory Mailed to permit holders in November, due within 45 days

Hazardous waste

You need a hazardous waste license if your business produces any amount of hazardous waste. Facilities in Anoka, Carver, Dakota, Hennepin, Ramsey, Scott, or Washington County are licensed and inspected by their county. Facilities in greater Minnesota are licensed and inspected by the MPCA. If you produce only small amounts of hazardous waste, you probably qualify to bring the wastes to PDF icon Very small quantity generators collection programs (w-hw2-51). See the Hazardous waste documents and forms page for information on managing specific types of hazardous waste, such as oil filters and oil-spill cleanup materials. Oily wastes generally don't require a hazardous waste license, but check with your county to be sure.

Hazardous waste due dates

Requirement Due date
Hazardous waste generators fee Mailed to license holders in first quarter, due date on invoice
License application Due August 1 for Greater Minnesota businesses;
Twin Cities metro businesses, contact your county

Storage tanks

Report leaks and spills to the Minnesota Duty Officer at 651-649-5451 or 800-422-0798. Most aboveground storage tanks larger than 500 gallons or underground tanks larger than 110 gallons have to be registered with the MPCA. See the storage tanks pages for more information.

Beyond compliance