Department of Toxic Substances Control Department of Toxic Substances Control

Regulatory Assistance Office

Regulatory Assistance Office

The Department of Toxic Substances Control (DTSC) Regulatory Assistance Officers respond to inquiries from the regulated community, environmental firms, other agencies, and the public at large about Department issues.

DTSC Regulatory Assistance Officer’s role is to provide informal guidance about hazardous waste management, site cleanup and other DTSC regulatory information for the convenience of regulated businesses, other government agencies and the public. Such advice is not binding upon DTSC, nor does it have the force of law. If you would like a formal opinion on a matter by DTSC, please contact the responsible program office directly.

Within California, you can contact a Regulatory Assistance Officer by calling (800) 728-6942. If you are calling from out-of-state, please call (916) 324-2439.

In addition to the toll free number, you may email questions directly to the Regulatory Assistance Officers at:


The Department of Toxic Substances Control (DTSC) Regulatory Assistance Program provides regulatory compliance assistance, information, research, and ombudsman services to the public. At its core are three Hazardous Substances Scientists, two in Southern California, one in Northern California Regional Offices (PDF map).  The Regulatory Assistance Officers respond to inquiries from the regulated community, environmental firms, other agencies and the public at large.  Typically, they respond to hundreds of calls per week and, increasingly, to emails.

Tapping into the Regulatory Assistance program gives you the benefit of a combined total of more than 40 years of experience in DTSC, shared by the Regulatory Assistance Officers alone. In addition to the traditional references (regulations, policies and procedures, and other documents) they rely on contacts in and outside of DTSC who are experts in specialized fields. What's more, the key DTSC programs provide on-call Regulatory Assistance Officer points-of-contact, further enriching the information resource.

You can contact the Regulatory Assistance Officers by calling (800) 728-6942, or (800) 72TOXIC. You will reach the Regional Regulatory Assistance Officer covering your part of the state.   If you are calling from out-of-state, you will need to call (916) 324-2439.  Or email them directly:

Email Regions Covered
Gloria Conti
(714) 484-5400

Southern California: Southern Los Angeles, Orange, San Diego and eastern counties
HQ Staff
(800) 728-6942 All other counties in California
Information about other Cal/EPA Boards and Departments can be obtained through their Ombudsmen or Public Affairs.

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

Program Contact Number(s)
Waste Alert Hotline (Complaints) (800) 698-6942 or (800) 69-TOXIC
California Temporary (90 day) EPA ID Numbers (800) 618-6942 or (916) 255-1136 if calling from outside the U.S.
California Permanent ID Numbers See Form 1358 (ID numbers are no longer issued by telephone)
EPA ID Numbers (US EPA) (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

DTSC Transportation Unit (haulers) (800) 618-6942