Oklahoma Brownfields Program

The Brownfields program of the Oklahoma Department of Environmental Quality (DEQ) has three parts: a certificate program that DEQ labels Certification Program/Liability Relief, free site assessments for eligible public and nonprofit entities, and low-interest loans for site cleanup.

In a Phase I ESA

DEQ's brownfields sites are an Oklahoma form of the state brownfield records that ASTM E1527-21 lists as a standard source. The general reading of a brownfields listing is on the Brownfields page. Oklahoma has a second brownfields program at the Corporation Commission, described on the Corporation Commission Brownfields page, so a brownfields search in Oklahoma has two agencies to cover.

• The certificate program is a cleanup record. DEQ says its Brownfields Certificate Program gives private parties and government entities a way to voluntarily investigate and, if warranted, clean up contaminated properties, resulting in a release of state and federal liability.
• An assessment may already exist. DEQ provides free Targeted Brownfields Assessments to eligible entities, which it names as non-profit and government entities such as cities, counties and tribes. DEQ says an assessment can be a Phase I Environmental Site Assessment, a Phase II, an asbestos survey, or other work tailored to the participant. If a property has been through one, ask for the report.
• Controls are tracked separately. DEQ's Brownfields pages link an Institutional Controls Database alongside the Brownfields Public Record. The pages read do not describe what the Institutional Controls Database holds, so open it for the property rather than assume.

DEQ says sites in its Voluntary Cleanup Program generally have the option to enter the Brownfields program if the participant asks, so check the Brownfields record for a site first found in the Voluntary Cleanup Program.

Where to look a site up

DEQ's Brownfields page links the Brownfields Public Record, the Institutional Controls Database, and an interactive map of DEQ brownfield sites.

Getting the file

DEQ's Central Records office holds the agency's files. Requests go through its online request form, in person at 707 N. Robinson in Oklahoma City, or by phone at 405-702-1188. DEQ asks that a request give the date range, the facility ID number or the facility or company name, any permit number, and whether the records wanted are land, air, water, or environmental complaints and local services documents.

Sources

Oklahoma Department of Environmental Quality pages, read October 1, 2026:

• Brownfields, last modified September 18, 2026.
• Brownfields Certificate Program, last modified September 18, 2026.
• Site Assessment and Investigation, last modified July 23, 2026.
• Voluntary Cleanup Program, last modified September 22, 2026.
• Central Records, last modified July 31, 2026.