The lawyer representing 58 former Bucksport millworkers has asked a federal judge to consider recent layoffs at the Catalyst paper mill in Rumford as evidence the U.S. Department of Justice should have required more divestments from Verso Paper Corp. in the purchase of its larger competitor, NewPage.

The justice department settlement is the latest frontier for the union’s fight against Verso’s closure of the Bucksport mill and its sale to Canadian scrap metal dealer American Iron & Metal last year.

Kimberly Tucker, Lincolnville-based lawyer for the International Association of Machinists and Aerospace Workers Local 1821, sent a response last week to U.S. District Court in Washington, D.C., where the antitrust settlement still needs court approval.

Tucker has challenged the justice department’s decision to exclude the Bucksport mill from its review of the $1.4 billion Verso-NewPage deal.

The department defended that decision in a filing in May, saying its investigation, which involved interviews of more than 100 customers, brokers and competitors, revealed the Bucksport mill was “less viable” than others and did not close as a result of the merger.

The antitrust settlement required Verso to sell its mills in Rumford and Biron, Wisconsin, to Canadian competitor Catalyst Paper Corp. at a price of $62.5 million to reduce the market control of the combined Verso-NewPage.

In a letter sent May 26, Tucker argued Catalyst’s May 22 announcement that it would lay off about 50 employees because of a prolonged shutdown of its No. 12 paper machine indicates it is supporting an increase in the price of coated paper since the Verso merger.

Tony Lyons, a spokesman for Catalyst, told the Sun Journal at the time the shutdowns and layoffs are “directly market related.”

The United Steelworkers Local 900 union, representing workers at the Rumford mill, wrote in a May 20 Facebook post cited by Tucker that “it appears the Catalyst plan to sell more product from our mill and gain customer base is not working as well as planned.”

If U.S. District Court Judge Tanya S. Chutkan of Washington, D.C., finds the settlement in conflict with the public interest, she could order modifications to the terms, which then could be fought in court.