Smokestacks tower over Hayden, north of Tucson, site of active and inactive Asarco smelters and mining operations.

Citing depressed copper prices, Tucson-based Asarco LLC says it will lay off up to 211 hourly workers as it plans to shut down its ore concentrator at Hayden and curtail some other operations.

Asarco — one of the region’s biggest employers — says it has proposed the indefinite shutdown of the Hayden concentrator as well as a reduction in stripping-for-leaching operations at the Ray Mine in response to a more than 40 percent drop in copper prices since 2011.

“The Company’s cost structure and current market conditions require operational adjustments in order to ensure its viability and sustainability as well as protect its mineral reserves for the longer term,” Asarco said in a news release.

Asarco said a total of 211 hourly positions “may be affected,” cutting the combined operations’ employee headcount to 1,637.

The company did not detail the exact timing of the layoffs, but under a required 60-day notification Asarco recently filed with the state and union, the layoffs could start in late October.

In March, Asarco laid off 130 employees from three of its four Arizona sites, including 35 at the Mission Mine south of Tucson near Sahuarita. The rest were from the company’s Ray Mine and its mill in nearby Hayden.

Asarco ranked 16th in the Star 200 survey of Southern Arizona’s largest employers with 2,427 full-time equivalent employees at the start of 2015. The company is owned by Mexican mining giant Grupo Mexico.

Asarco’s union employees have been working without a contract since June, after negotiations with the company reached an impasse and the union terminated the prior contract. The unions, led by the United Steelworkers, and the company both have filed pending complaints of unfair labor practices with the National Labor Relations Board.

The company said the plant cutbacks will curtail the company’s production by about 67 million pounds per year, or 17 percent of total production.

Combined with a planned $110 million cut to capital spending for 2015-2016, the moves will “improve the company’s overall costs and free cash flow,” Asarco said.

“Economic conditions will continue to be reviewed and adjustments may be made as market conditions warrant,” Asarco said. “The Company looks forward to improved future economic circumstances and maintains its commitment to a sustainable business all for the benefit of its employees, vendors, customers and communities in which it operates.”


Become a #ThisIsTucson member! Your contribution helps our team bring you stories that keep you connected to the community. Become a member today.

Contact Assistant Business Editor David Wichner at dwichner@tucson.com or 573-4181. On Twitter: @dwichner