Regulatory Assistance Office


The Department of Toxic Substances Control (DTSC) Regulatory Assistance Program provides regulatory compliance assistance, information, and research services to the generators, transporters, and facilities managing hazardous waste. We also provide assistance to other government entities and the public.

DTSC Regulatory Assistance Officers provide informal guidance only about the management of hazardous waste, as well as cleanup operations, for the convenience of the public. Such oral or electronic mail advice is not binding upon DTSC, nor does it have the force of law. You should also refer to the statutes and regulations, DTSC policies and procedures, and other formal documents.

If you would like a formal opinion on a matter by DTSC, please contact the responsible program office directly.

Contact the Regulatory Assistance Office: Call from CA: (800) 728-6942 or (800) 72TOXIC. Call from out-of-state: (916) 324-239. Send email to: 

Information about other Cal/EPA Boards and Departments can be obtained through their Ombudsmen or Public Affairs.

Finally, other DTSC programs have program-specific Duty Officers, liaisons and contacts. Here are a few key DTSC contact numbers:


Waste Alert Hotline (Complaints)


ID Numbers (State and Federal EPA)


Transportation Unit (haulers)

Contact Number(s)

(800) 698-6942 or (800) 69-TOXIC


(800) 618-6942

NOTE: For an after-hours emergency ID number (Example: spills and clandestine lab cleanups), please call the Office of Emergency Services at (800) 852-7550



Send an email to