Hazardous Waste

Minnesota has an extensive program for the “cradle-to-grave” management of hazardous waste. Every business in Minnesota is responsible for determining if the waste it produces is hazardous. Many types of businesses, organizations, non-profit groups and governments generate hazardous waste in the course of providing their products or services, including but not limited to the

following: cleaning and maintenance; chemical manufacturing and formulating; construction; equipment repair; health care providers; furniture manufacturing and refinishing; wood preservation; laboratories; laundries and dry cleaning; metal manufacturing; electroplating; transportation; electronics; textile, plastics, and leather manufacturing; pesticide manufacture and application; printing and photography; schools and colleges; vehicle repair and auto body shops; and utilities.

Wastes may be hazardous by either exhibiting a hazardous-waste characteristic or by being listed as a hazardous waste.

Characteristic wastes include:

  • Ignitable waste. A liquid is ignitable if it has a flash point less than 140 degrees Fahrenheit. Check the product’s label or Material Safety Data Sheet (MSDS) for this information. A nonliquid waste is ignitable if, at a standard temperature and pressure it can cause a fire through friction, absorption of moisture, or spontaneous chemical changes, and burns so persistently that it creates a hazard.
  • Oxidizing waste. An oxidizer adds oxygen to a reaction or fire in the absence of air. Oxidizing wastes often have chemical names beginning with “per…” or ending with “…oxide” or “…ate” (for example: persulfate and chlorate). Many oxidizing wastes also contain nitrogen or halogens such as fluoride, chlorine, bromine, and iodine.
  • Corrosive waste. Any water-based waste having a pH of 2 or less (an acid) or 12.5 or more (a base) is corrosive. Check the product’s label or MSDS for this information. A corrosive waste may also be a liquid that is able to corrode greater than one-fourth of an inch of steel per year at 130 degrees Fahrenheit.
  • Reactive waste. . Unstable or explosive wastes, wastes that react violently when brought in contact with water, and wastes that release toxic vapors (such as hydrogen cyanide or hydrogen sulfide) are considered reactive and hazardous (example of reactive waste: unspent lithium batteries greater than 9 volts).
  • Lethal waste. Lethal wastes exhibit oral or dermal values (LD50) or inhalation values (LC) below a certain lethal threshold. If the health hazard data on the MSDS or other information leads you to suspect a waste may be lethal, contact your metropolitan county (Anoka, Carver, Dakota, Hennepin, Ramsey, Scott or Washington) or MPCA district office hazardous waste staff for assistance.
  • Toxic waste. Wastes are considered toxic if using the Toxicity Characteristic Leaching Procedure (TCLP), they leach metals or organics at or above certain threshold values. A list of T.C. chemicals and their maximum allowable concentrations is available on the MPCA website at www.pca.state.mn.us under Waste Publications.

Listed hazardous wastes are printed in Minnesota Rules 7045.0135 and include the following:

  • Many spent chlorinated solvents used for degreasing (carbon tetrachloride, methylene chloride, trichloroethane, trichloroethylene, and others);
  • Many other waste solvents, cleaners and strippers (acetone, butyl alcohol, carbon disulfide, cresol, ethyl acetate, methyl ethyl ketone (MEK), methyl isobutyl ketone (MIBK), methyl or wood alcohol, toluene, xylene, and others);
  • Certain wastes derived from products containing ten percent or more of the above solvents;
  • Residues from distillation units (or other similar systems) used to recover the above solvents;
  • Most wastes from electroplating operations (cleaning and stripping tank solutions, plating bath solutions and sludges, and sludges from pre-treatment of wastewater);
  • Certain wastes from the heat treatment of metals;
  • Wastes produced during specific manufacturing processes (certain chemicals, explosives, inks, and pigments), petroleum refining and steel finishing (pickle liquor);
  • Many unusable or off-specification commercial products: aniline, certain antibiotics, arsenic compounds, benzenes, chloroform, creosote, cyanide compounds, formaldehyde, hydrofluoric acid, hydrogen sulfide, lead compounds, mercury compounds, naphthalene, many nitrogen compounds, many pesticides, and pentachlorophenol (penta);
  • Phenols and pyradine; and
  • Polychlorinated biphenyls (PCBs) at concentrations greater than 50 parts per million.

The four lists of hazardous waste (F, K, P and U) are available on the MPCA website at www.pca.state.mn.us under Waste Publications.

Hazardous waste must be managed in accordance with Minnesota hazardous-waste rules. The generator requirements are summarized as follows:

  • Obtain a hazardous waste identification number (formerly called an EPA identification number) (at no cost) by filling out the Notification of Hazardous-Waste Activity and sending it to the MPCA. This form, instructions, and assistance for completing the form may be obtained from the MPCA or the appropriate metropolitan county hazardous-waste program.
  • Next, a company may have to apply for a hazardous-waste generator license from the MPCA (for businesses located in greater Minnesota) or from the appropriate metropolitan county (for businesses located in the seven-county metropolitan area).
  • Hazardous-waste containers must be properly marked and labeled. As soon as a waste is put in a container, it must be marked with the words “hazardous waste,” an accumulation start date, and an easily understood description of the waste.
  • Prior to off-site shipment, most hazardous wastes must be placed in specific Minnesota Department of Transportation (DOT) containers and labeled with a DOT hazard label and hazardous-waste label. For more information, contact the MPCA or your metropolitan county office.
  • Store hazardous waste properly and restrict its accumulation time and amounts to specified limits as noted below.

Indoor storage of hazardous waste is regulated by fire prevention and building codes, in addition to hazardous-waste rules. Containers must be stored closed, with adequate aisle space between them for easy access and inspection. Floor drains must not allow waste to escape.

Hazardous waste stored outdoors must be in an area where access is restricted. The waste must be stored on a curbed, impermeable surface, and, if ignitable, must also be protected from direct sunlight.


CREDITS: This is an excerpt from A Guide to Starting a Business in Minnesota, provided by the Minnesota Department of Employment and Economic Development, Small Business Assistance Office, Twenty-eighth Edition, January 2010, written by Charles A. Schaffer, Madeline Harris, and Mark Simmer. Copies are available without charge from the Minnesota Department of Employment and Economic Development, Small Business Assistance Office.

This post is also part of a series of posts on Minnesota Environmental Protection Programs and how they affect starting a business in Minnesota.