Types of Hazardous Waste

You must assume a waste is hazardous unless you document it to be exempt or non-hazardous. This process is called evaluation.

How to evaluate a waste

1. Refer to the Minneosta Pollution Control Agency's fact sheet on waste evaluation (PDF).
2. Create a list of all wastes generated at your business. Talk to purchasing, production and maintenance personnel. Tour all indoor and outdoor areas, especially storage, production lines and dumpsters. Include sewered and recycled wastes.
3. Evaluate each waste. Determine if it is considered exempt, has one or more hazardous characteristics (see below), or is on one of the hazardous waste lists (see below). You may need to have the waste tested.
4. Keep evaluation documentation for at least three years after you stop generating the waste.

If your business generates hazardous waste, you must have a hazardous waste license.

If a waste has a hazardous characteristic, it's a hazardous waste. Refer to the Minnesota Pollution Control Agency's fact sheet (PDF) for more information.

Ignitable

• Ignitable wastes have flash points less than 140 degrees Fahrenheit or ignite spontaneously and burn vigorously.
• The Safety Data Sheet (SDS) will give the flash point of the product. This will likely be close to the flash point of the waste unless the waste is contaminated with materials with a low flash point, such as gasoline.
• Examples: Mineral spirits, many petroleum based parts washer solvents, alcohols, etc.
• Waste code: D001.

Oxidizer

• Oxidizing wastes supply oxygen to a fire in the absence of air.
• The SDS will usually indicate if the product is an oxidizer.
• Examples: Oxides, permanganates, nitrates, etc.
• Waste code: D001.

Corrosive 

• Corrosive wastes have a pH of 2.0 or less, 12.5 or more, or are able to corrode steel at a rate greater than 1/4 inch per year.
• The SDS will often give the pH of the product. Diluting the product prior to use or the actual use of the product may change the pH so the waste is non-hazardous. Some corrosive wastes may be able to be neutralized and discharged to a sanitary sewer. Check with Metropolitan Council Environmental Services for details.
• Examples: Strong acids and bases.
• Waste code: D002.

Reactive

• Reactive wastes are unstable, react violently or form potentially explosive mixtures when mixed with water, or can produce toxic gases.
• The reactivity hazard data section of the SDS may indicate the product is hazardous.
• Examples: Explosives and some cyanide bearing wastes.
• Waste code: D003.

Toxic 

• A toxic waste leaches any of 40 contaminants at a concentration greater than the thresholds in Minn. Rules 7045.0131, Subp. 8.
• Examples: Used parts washer solvent, fluorescent lamps or paints containing heavy metal pigments.
• Waste codes: D004 to D043, depending on type of contaminant.

Lethal

• Lethal wastes (PDF) can cause severe health effects when ingested, inhaled or absorbed through the skin.
• The health hazard data section of the SDS may provide information to help determine if a waste is lethal.
• Examples: Some pesticide or arsenic wastes.
• Waste code: MN01.

Listed hazardous wastes either contain PCBs above 50 ppm or appear on one of four lists (F, K, P or U) found in Minnesota Rule.

Polychorinated biphenyls (PCBs)

PCBs - are classified as non-PCB (less than 50 ppm PCBs), PCB-contaminated (50 ppm to less than 500 ppm) or PCB (500 ppm or greater). In Minnesota, a waste that is either PCB-contaminated or a PCB has a waste code of MN03.

F list

F list - includes waste solvents, wastewater treatment sludges and electroplating baths, sludges, and related wastes. Examples of F listed wastes include many paint and lacquer thinners, some types of brake and carburetor cleaners, vapor degreasing and dry cleaning solvents, and distillation bottoms.

K list

K list - includes wastes that are the result of a specific industry process, like wood preserving, the manufacture of pesticides, explosives, inks, organic or inorganic chemicals and inorganic pigments, petroleum refining, and iron and steel industries.

P list and U list

P list and U list - check these lists if disposing of unused or usable chemical products or spill residues. To be P or U listed, the P or U chemical must comprise 100 percent of the waste or be the sole active ingredient of the product.

While not a regulatory designation, small amounts of unrelated but compatible chemicals may be packaged for shipment in a common container. This is called a lab pack.

The generic waste code for a lab pack is MN02. Up to five additional waste codes can be included in a shipping manifest.