Understanding RCRA Hazardous Waste Categories
Under 40 CFR 262.13, the EPA regulates hazardous waste generators based on the total mass of hazardous waste generated in a calendar month. It is the facility's responsibility to count its waste accurately every month to determine its regulatory status.
Your category dictates everything from how long you can accumulate waste on-site without a permit to the level of emergency preparedness documentation required.
The Three Generator Categories: VSQG, SQG, and LQG
Very Small Quantity Generators (VSQGs) generate 100 kilograms (approx. 220 lbs) or less of non-acute hazardous waste per month.
Small Quantity Generators (SQGs) generate between 100 kg and 1,000 kg (approx. 2,200 lbs) of non-acute hazardous waste per month.
Large Quantity Generators (LQGs) generate 1,000 kilograms or more of non-acute hazardous waste per month, or more than 1 kg of acutely hazardous waste.
How to Calculate Monthly Hazardous Waste Generation
To determine your category, sum the weights of all solid waste streams that exhibit a hazardous characteristic (ignitability, corrosivity, reactivity, toxicity) or are specifically listed by the EPA.
Calculation Method: Total all non-acute hazardous waste generated from the first day to the last day of the calendar month. Example: If in March you produce 150 kg of spent solvent and 50 kg of paint waste, your total is 200 kg. For that month, you operate under SQG regulations.
Acute Hazardous Waste and Episodic Generation
Acutely hazardous wastes (such as P-listed chemicals) have drastically lower thresholds due to their extreme danger. Generating just over 1 kilogram (2.2 lbs) of acute hazardous waste in a single month immediately pushes a facility into LQG status.
If a facility normally operates as a VSQG or SQG but experiences a one-time event (like a chemical cleanout or spill) that spikes their generation, they may qualify for episodic generation rules under 40 CFR 262 Subpart L, allowing them to temporarily manage the waste without upgrading their permanent category.
Frequently asked questions
Do I count waste accumulated on-site or waste generated?
Your category is determined strictly by the amount generated in a calendar month, not the total amount accumulated on-site over time.
Does universal waste count toward my RCRA threshold?
No, universal wastes (such as fluorescent lamps, common batteries, and mercury-containing equipment) managed under 40 CFR Part 273 do not count toward your monthly generator category calculation.
What happens if I exceed my threshold for only one month?
Historically, this meant adhering to the stricter category rules for that month. Under the newer Hazardous Waste Generator Improvements Rule, you may notify the EPA of an 'episodic event' to maintain your lower status, provided conditions are met.
Do I need to count hazardous wastewater?
If the hazardous wastewater is treated immediately in an exempt wastewater treatment unit (WWTU) regulated under the Clean Water Act, it generally does not need to be counted toward your generator status.