The Benson Mines plant site is now a post-industrial environmental remediation site in the Adirondacks. Industrial activity started here in the early 1800s, as one of the many small iron ore deposits in the Adirondacks that were mined periodically over the next century. Operations ramped up during World War II, when the federal government’s Defense Plant Corporation built a production plant there to supply iron ore sinter to steel plants in Pittsburgh and Cleveland, by rail. After the war, the plant was sold back to the Jones and Laughlin Steel Corporation, and the operation continued to grow, reaching a peak in 1960, with a thousand employees. The mine closed in 1978, leaving a two-mile-long pit to fill with groundwater, and more than a thousand acres of tailings spoils. In the 1980s oil was detected in an adjacent river, and a 1,000-foot-long, 15-foot-deep plastic-lined trench was built in an attempt to keep contaminants contained. When it failed to do so, the plant site became an EPA cleanup site, in 2013, and remediation continues.