Notice of Start Sixth Five-Year Review for the Double Eagle and Fourth Street Superfund Sites

Notice of Start Sixth Five-Year Review for the Double Eagle and Fourth Street Superfund Sites The Oklahoma Department of Environmental Quality (DEQ) and the U.S. Environmental Protection Agency (EPA) are conducting the sixth Five-Year Review for the Double Eagle (EPA ID# OKD007188717) and Fourth Street (EPA ID# OKD980696470) Superfund Sites in Oklahoma City, Oklahoma. The purpose of this review is to determine whether the site remedies remain protective of human health and the environment, as outlined in the Records of Decision (RODs) and/or remedial design. It also assesses whether land use restrictions are in place and protective. Five-year reviews of remedies at Superfund sites are required when waste is left in place. For these sites, shallow groundwater remains contaminated. The review will document the methods, findings, and conclusions in a report. The Sixth Five-Year Review report will be available to the public in May 2027. The Double Eagle and Fourth Street Superfund Sites are adjoining properties in Oklahoma City, Oklahoma, near the intersection of Martin Luther King Avenue and NE 4th Street. These two sites share similar past operations, contaminants of concern, a common groundwater operable unit, and similar RODs. The contaminants found at these sites were primarily organic chemicals and heavy metals related to oil refinery processes. Both facilities operated as used oil re-refiners over many years. Historical operations resulted in wide-spread disposal of residual waste, mostly in pits, on both sites. These pits were generally acidic tar sludges with high lead concentrations. The sites were officially added to the National Priorities List (NPL) list in March 1989. A ROD for both sites, which included a remedy for contaminated soil and surface contamination, was published on September 28, 1992. The ROD is a legally binding document that outlines the remedy for the sites. On both sites, the acidic sludges were neutralized, stabilized, and transported offsite for disposal in a landfill authorized to accept this hazardous waste material. The excavated areas were filled with clean soil and vegetated. The cleanup was completed in 1999. A second ROD, addressing the groundwater for the Fourth Street Site, was published on September 30, 1993, while a third ROD, addressing the groundwater for the Double Eagle Site, was published on April 19, 1994. The groundwater in the alluvial and shallow Garber-Wellington aquifers under the sites is currently contaminated with chlorinated solvents, hydrocarbons, and metals from refining operations. The selected remedy for groundwater was natural attenuation and routine monitoring. In 2006, EPA issued an Explanation of Significant Differences (ESD) for both sites that documents EPA's final decision to discontinue further groundwater monitoring after confirming the aquifer is a Class III aquifer (non-usable due to high total dissolved solids content of the water), conditions support natural reduction of the contaminants, and the potential receptors (surface water and useable groundwater supplies) are not likely to be affected. In 2008, EPA deleted the sites from the National Priorities List (NPL). DEQ continues to inspect the sites and the surrounding area to ensure no drinking water wells are placed near the sites. More information, including current and previous Five-Year Review reports, is available at the following websites: • https://oklahoma.gov/deq/divisions/land-protection/cleanup-redevelopment/superfund.html • https://www.epa.gov/superfund/double-eagle-refinery • https://www.epa.gov/superfund/Fourth-Street-Abandoned-Refinery DEQ will be conducting interviews as part of the Five-Year Review for the Double Eagle and Fourth Street sites. If you wish to be interviewed, have any questions, or need further information concerning the sites, please contact: Makenna Hartman Oklahoma Department of Environmental Quality Land Protection Division 707 North Robinson, PO Box 1677 Oklahoma City, OK 73101 Work: (405) 702-5159 Email: makenna.hartman@deq.ok.gov Erica Almance EPA Region 6 Remedial Project Manager Work: (214) 665-6690 Email: almance.erica@epa.gov All media inquiries should be directed to the EPA Region 6 Press Office at 214-665-2200. LPXLP April 28 2026 LOKL0506434