The Tybouts Corner Landfill Site is located in New Castle County, Delaware approximately 10 miles south of Wilmington and four miles west of the Delaware River. The Site was used by the New Castle County Department of Public Works as a municipal sanitary landfill that also accepted industrial wastes from December 1968 until July 1971.

The landfill consisted of two noncontiguous sections, a west landfill that was about four acres in size and the main landfill that was about 47 acres, ranging from five to 40 feet thick. Contamination was found in two nearby wells in 1976 and again in 1983.

Due to concerns that contamination from the landfill could impact the Potomac aquifer, a major drinking water source, the Site was listed on the National Priorities List. The Site never impacted the Potomac aquifer.