Army Creek Landfill - Army Creek Marsh Restoration. Army Creek is a superfund site in New Castle, Delaware. The 60-acre landfill site was used to dump industrial wastes between 1960 and 1970. Rainwater percolating through the landfill contaminated the groundwater used for drinking by 1970. The restoration plan proposes to restore injured natural resources by increasing the quality and quantity of wetland and upland available for resources within the Army Creek watershed.