Sheridan Disposal Services

Overview

Sheridan Disposal Services is a 110-acre former commercial waste disposal facility in Waller County, near Hempstead, Texas. The company operated from about 1958 to 1984, disposing of organic and inorganic chemicals and solid wastes through steam distillation, open burning, and incineration. Those operations left hazardous contamination in soil and groundwater across the site. EPA added the site to the National Priorities List (NPL), the federal list of priority Superfund cleanup sites, in March 1989.

Thirteen contaminants of concern have been identified at the site. Groundwater contains arsenic, benzene, tetrachloroethene, toluene, trichloroethane, and trans-1,2-dichloroethene. Sludge contains benzene, naphthalene, petroleum, phenol, polychlorinated biphenyls (PCBs), toluene, and zinc. Soil contains PCBs. Drinking contaminated groundwater is the greatest health concern. Cleanup is organized into two main areas: source control in the original disposal zone and groundwater migration management in the area where contaminants spread.

For the source control area, EPA originally selected capping, onsite containment, and in-situ bioremediation in a 1988 decision. A 2002 amendment updated that plan to use onsite containment and in-situ solidification and stabilization instead. Remedial action work began in April 2005, and construction was completed in May 2006. For groundwater migration, EPA chose monitored natural attenuation and institutional controls, meaning the groundwater is tracked over time to confirm contaminant concentrations naturally decrease. Long-term groundwater monitoring began in July 2006 and remains ongoing.

EPA has determined that human exposure is under control across the entire site and that groundwater migration is stabilized. All cleanup goals for current and reasonably anticipated future land uses have been met, and required land-use controls are in place. The site achieved readiness for anticipated reuse in September 2007. Five-year reviews have been conducted regularly to confirm the remedy stays protective. The most recent five-year review was completed in September 2025. A 2020 review also confirmed the remedy protects human health and the environment. The site has not yet been deleted from the NPL.

Community members with questions can contact the EPA Community Involvement Coordinator or the Remedial Project Manager. For state-related questions, contact the Texas Commission on Environmental Quality (TCEQ).