The U.S. Department of Justice and the U.S. Environmental Protection Agency (EPA) announced a settlement with ASARCO requiring the company to spend $150 million to install new equipment and pollution control technology to reduce emissions of toxic heavy metals at a large smelter located in Hayden, Arizona. The company will also fund local environmental projects valued at $8 million, replace a diesel locomotive with a cleaner model for $1 million, and pay a $4.5 million civil penalty.

An EPA investigation found the company violated federal Clean Air Act standards by failing to adequately control emissions of hazardous air pollutants, such as arsenic and lead, from the Hayden smelter. Under the settlement, ASARCO will install new and upgraded ventilation hoods to capture hot flue gases from its furnaces to better capture the PM, which includes the hazardous air pollutants, and SO2. The company will also replace an aging electrostatic precipitator with a new, cleaner baghouse and inject high performance lime to reduce SO2 emissions. To reduce wind-blown dust from the facility, which contains varying levels of heavy metals, the company will implement an improved dust control plan, including the use of wind fences, upgraded water sprayers and the installation of concrete pads.

In addition, ASARCO will operate five ambient air monitors in and around the Hayden and Winkelman communities to track levels of pollutants, including arsenic, lead and PM, and will make additional improvements to dust controls if levels are high.

The federal enforcement action targeted hazardous air pollutants, including lead and arsenic, and particulate matter (PM). With the controls in place, the hazardous air pollutants should be reduced by at least 8.5 tons per year (t/y), and PM emissions are expected to be reduced by 3,500 t/y. The new equipment and controls will also slash the facility’s sulfur dioxide (SO2) emissions by 19,000 t/y, a reduction of more than 90%, according to EPA estimates. Currently, the ASARCO smelter is the largest source of SO2 emissions in Arizona.

The settlement also requires ASARCO to spend $8 million to fund two environmental mitigation projects. Of this, $6 million will be used on a road paving project in Pinal County that will reduce dust pollution on local dirt roads close to the towns and benefit residents exposed to PM emissions. In addition, $2 million will be provided to the Gila County Environmental Health Services to conduct lead-based paint testing and abatement in homes, schools and other public buildings in the towns of Hayden and Winkelman.

Built in 1912 and expanded over the years, the ASARCO Hayden site is a copper ore processing, concentrating and smelter facility. The ASARCO plant includes a crusher, concentrator, smelter and tailings impoundment areas and produces 300 million to 400 million lb of copper and more than 500,000 tons of sulfuric acid annually. It is owned by Grupo México.