November 2024 

This page was created by the Department of Toxic Substances Control (DTSC) Regulatory Assistance Officers and is intended to provide a simple overview of accumulation time limits for hazardous waste generators. Additional generator requirements are also discussed on DTSC’s Hazardous Waste Generator Summary Chart and Hazardous Waste Generator Requirements webpages. We advise you to review these other resources as well, and to consult with your local Certified Unified Program Agency (CUPA) for additional resources.

How Long Can I Accumulate Hazardous Waste Onsite?

The answer depends mainly on your generator status. Small quantity generators (SQGs) can store most wastes onsite for up to 180 days per Title 22 of the California Code of Regulations (22 CCR) 66262.16(b), or for up to 270 days if offering their hazardous waste for transportation over a distance of 200 miles or more, per 22 CCR 66262.16(c). Large quantity generators (LQGs) can store most wastes onsite for up to 90 days per 22 CCR 66262.17(a). You can determine your generator status using the table in 22 CCR 66262.13.

Hazardous waste generators are required to demonstrate that hazardous waste held in containers has not exceeded the relevant accumulation time limit by marking each container with its accumulation start date, per 22 CCR 66262.16(b)(4)(A)6. for SQGs and 22 CCR 66262.17(a)(5)(A)6. for LQGs. A similar requirement to mark tanks used for accumulating hazardous waste with an accumulation start dates exists in 22 CCR 66262.16(b)(4)(B)3. for SQGs and 22 CCR 66262.17(a)(5)(B)3. for LQGs.

Demonstrating that accumulation time limits have been met for hazardous waste being held in continuous use or flow-through tanks is more complex. Generators of hazardous waste using a tank in a batch process must demonstrate that the tank has been emptied of hazardous waste as completely as possible at least once prior to meeting the accumulation time limit for hazardous waste that has entered the tank. Generators of hazardous waste using a flow-through tank must demonstrate that the volume of the hazardous waste flowing through the tank during the applicable time period is greater than the volume of the tank. These requirements are described in 22 CCR 66262.16(b)(4)(B)4. for SQGs and 22 CCR 66262.17(a)(5)(B)4. for LQGs.

What is “Satellite Accumulation” and How are the Requirements Different?

Using satellite accumulation, a generator may accumulate limited quantities of hazardous waste at or near a point of waste generation for up to one year if all of the applicable satellite accumulation provisions in 22 CCR 66262.15 are met. For more information on the satellite accumulation provisions, please see DTSC’s Satellite Accumulation webpage.

When Does My Accumulation Time Clock Start?

For most hazardous waste generators, the accumulation time clock for hazardous waste starts on the date that the hazardous waste is generated per 22 CCR 66262.16(g)(2) for SQGs and 22 CCR 66262.17(e) for LQGs. However, for SQGs that do not generate more than 100 kg of non-acute hazardous waste per calendar month or 1 kg of acutely or extremely hazardous waste per calendar month, the accumulation time clock begins on the date the generator has accumulated either 100 kg of non-acute hazardous waste or 1 kg of acutely or extremely hazardous waste per 22 CCR 66262.16(g)(1).

Summary of Accumulation Time Limits

Is it Possible to Request an Accumulation Time Limit Extension for my Hazardous Waste?

Accumulation time limit extensions can be granted under limited conditions. In most cases, extensions are not granted unless requested before the the applicable accumulation period ends. For more information on accumulation time limit extensions, visit DTSC’s 30-Day Storage Extension Application for Hazardous Waste Generators webpage.

Disclaimer

DTSC Regulatory Assistance Officers provide guidance regarding management of hazardous waste for the convenience of the public. Such guidance is not binding upon DTSC, nor does it have the force of law. RAO guidance does not supersede the applicable statutes in California Health and Safety Code, Division 20, Chapter 6.5 and regulations in 22 CCR Division 4.5.