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Clean Diesel

Contact Us About Clean Diesel

Mailing Address:
US EPA Clean Diesel
1200 Pennsylvania Ave
Mail Code 6406A
Room 5358K (Overnight) 
Washington, DC 20450

Report a Violation
Report possible violations
of environmental laws and regulations

Clean Diesel Helpline

For information about clean diesel funding, diesel technologies or the DEQ contact our helpline.
Phone: 1-877-623-2322
Email: Clean Diesel Helpline (
Email Updates: Sign up to receive email updates on clean diesel funding and issues


Questions and Comments

Please use the form below to send us questions or comments. Be sure to include your e-mail address if you’d like a response.