Underground storage tank closures

If you are temporarily or permanently closing your underground storage tanks, the items below may be required. Be sure to also check with your local city and county authorities to determine if there are additional requirements associated with your tanks.

Temporary closure

Required forms: Temporary Closure Notice

Returning tanks to operation, after temporary closure

Required Forms: Operational Status Notice 

Permanent closure

Required forms:

The author of this report must be ICC-certified, a registered professional engineer, or a licensed hydrogeologist.

Required documents: Site Assessment/Report


All forms, checklists, and reports must be submitted to:
Department of Ecology
Underground Storage Tanks
P.O. Box 47655
Olympia, WA 98504-7655