Mallard Bay Landing Bulk Plant is a 10-acre former crude oil refinery and hazardous waste treatment facility in Cameron Parish, Grand Cheniere, Louisiana. The facility handled petroleum refining wastes from 1980 to 1983 and formally closed in 1987 after the owners filed for bankruptcy. EPA added the site to the Superfund National Priorities List in July 2000 after finding volatile organic compounds and metals had contaminated the property.
Six contaminants of concern were identified in groundwater across the site: arsenic, benzene, bromodichloromethane, carbon tetrachloride, chloroform, and manganese. EPA determined each posed an unacceptable risk to human health or the environment based on the amounts present and potential exposure pathways.
Cleanup happened in two phases. A removal action from November 1998 through August 1999 addressed immediate threats. Workers sampled the site, decontaminated equipment, and removed tank materials and waste, including over 824,000 gallons of tank material shipped off-site by barge and truck. The main remedial action ran from June 2003 through August 2004 and included extracting and stabilizing contaminated sludge and soil, removing underground piping and building structures, and disposing of drummed and stockpiled waste. The Record of Decision was issued in March 2003, with an amendment in July 2003 adding thermal treatment and offsite recycling as additional cleanup methods. Construction was completed in September 2003.
EPA deleted the site from the National Priorities List on September 19, 2005. No hazardous substances remain above levels that would prevent unlimited use and unrestricted exposure. Human exposure is under control, and contaminated groundwater migration is stabilized with no unacceptable discharge to surface water. EPA continues monitoring to confirm contaminated groundwater stays within the original area. The site is currently used by Talen's Marine as a staging and storage area, and as of December 2024, one on-site business was documented.
Community members with questions can contact the EPA Community Involvement Coordinator or the Remedial Project Manager. For state-related questions, contact the Louisiana Department of Environmental Quality.
