The Southern Pacific Transportation Company (Southern Pacific) conducted wood treating operations at the property located at 4910 Liberty Road in Houston, known as the Houston Wood Preserving Works (HWPW), from 1911 to 1984. Union Pacific Railroad (Union Pacific) acquired the property through its merger with Southern Pacific in 1997. Southern Pacific began cleanup efforts under the U.S. Environmental Protection Agency’s (EPA) Resource Conservation and Recovery Act (RCRA) cleanup program, which were supervised by the Texas Commission on Environmental Quality (TCEQ). Following the merger, Union Pacific continued the cleanup work that Southern Pacific began. The work is still performed under the authority of a federal RCRA permit, which dictates how investigations and cleanup activities are conducted at the site. The permit requires Union Pacific to adhere to all applicable environmental laws and regulations and coordinate all investigations and cleanup activities with the TCEQ. All work at the site has been reviewed, approved and conducted under TCEQ’s oversight.