Asarco completed a major pollution-control retrofit of its Hayden Smelter in 2018.

Tucson-based copper producer Asarco LLC has won more time to file an appeal with the U.S. Supreme Court to reverse rulings that it must pay millions of dollars in copper-price bonuses to current and former workers.

Asarco has been fighting to avoid paying the bonuses since 2014, when an abritrator ruled workers not eligible for the company’s pension plan should get the bonuses because that provision was mistakenly left out of a collective-bargaining agreement signed in 2011.

The bonus payments were upheld by a federal district court, and the 9th U.S. Circuit Court of Appeals rejected Asarco’s appeal for a second time in January.

Under court rules, Asarco had until April 10 to petition the Supreme Court for a writ of certiorari, which directs the appeals court to submit the case record to the high court for review.

But the company requested an extension, citing the near-term caseload of its lead attorney, and on March 29, Justice Elena Kagan approved an extension until May 10.

The unions say Asarco owes about 750 current and former workers more than $10 million in unpaid price bonuses and interest. The bonus is paid when the average quarterly copper price tops $1.60 per pound; the metal has been trading lately at about $2.90 per pound.

Meanwhile, Asarco’s union hourly employees have worked without a new contract since the last collective-bargaining agreement expired at the end of November, and negotiations have become contentious.

The United Steelworkers and several other unions represent more than 2,000 hourly workers at five Asarco locations in Arizona and Texas.

In December, union members authorized their bargaining committee to call a strike if talks broke down.

The Steelworkers recently said in online posts and newspaper ads that Asarco’s contract proposals have included β€œno wage increases and unnecessary cuts to our health insurance and other benefits.”

Asarco has declined to comment on the contract negotiations or the copper-price bonus case.

In Arizona, Asarco operates the Mission Mine in Sahuarita south of Tucson, the Silver Bell Mine in Marana and the Ray Mine and Hayden smelter in Central Arizona.


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Contact senior reporter David Wichner at dwichner@tucson.com or 573-4181. On Twitter: @dwichner. On Facebook: Facebook.com/DailyStarBiz