Asarco Copper Smelter, Texas

Two large smokestacks, one more than 800 feet tall, used to loom over the Rio Grande, here on the western edge of El Paso, part of a large copper smelter that operated here for many decades. The plant was closed in 1999, and the smokestacks torn down in 2013. The site is undergoing remediation. The owner of the plant, Asarco, was the dominant copper producer in the USA for many years, and had smelters and refineries coast to coast, processing ore from its mines in Arizona. It now has just one smelter left, in Hayden, Arizona, and one refinery, in Amarillo. The burial mound for the plant is managed by a company called Project Navigator, which handles a number of environmentally challenging legacy sites around the country.