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(Adds details of vote, BP comment)
HOUSTON, May 11 (Reuters) - Striking workers at BP Plc's Whiting, Indiana, refinery ratified a new four-yearcontract on Monday, formally ending a three-month work stoppage,said the president of the United Steelworkers local chapterrepresenting the hourly employees.
The workers are scheduled to begin returning to work on May18 in staggered groups, said USW Local 7-1 President Dave Danko.
"In the next couple of weeks, all we want to focus on ismaking a safe transition at the refinery," Danko said.
BP has kept the refinery in operation using temporaryreplacement workers since Feb. 8 when USW members walked out aspart of the largest strike by U.S. refinery and chemical plantworkers in 35 years.
Jorge Lanza, the Whiting refinery manager, said the companylooks forward to the workers' return beginning on May 18. "Ourreintegration process is expected to take about three weeks,through an orderly, smooth process that focuses on safety andpromotes teamwork."
The ratification was expected following agreement on Fridaybetween BP and Local 7-1 on the terms of bringing the 1,060union refinery workers back to their jobs. The two sides reacheda tentative contract agreement on May 1.
Danko said the vote was 92 percent in favor of the newcontract, which provides a 2.5 percent pay increase in the firstyear, a 3 percent increase in the second and third years and a3.5 percent boost in the fourth year.
The national strike eventually expanded to workers at 15plants including 12 refineries that account for one-fifth ofU.S. capacity. It began after talks broke down betweennegotiators for the USW International union and U.S. refineryowners over tighter standards to prevent worker fatigue and theuse of contractors in day-to-day plant maintenance.
An agreement was reached on March 12 on national issuesincluding pay, benefits and the fatigue and contractor issues,but strikes continued over local issues at the Whiting refineryand others.
The major sticking point at Whiting was the union's right tobargain under the contract over policies such as those thataffect worker safety at the refinery.
Workers are still on strike at the refinery in Toledo, Ohio,co-owned by BP and Husky Energy.
Negotiations also are continuing between striking workersand Marathon Petroleum Corp's Galveston Bay Refinery inTexas City, Texas. (Reporting by Erwin Seba; Editing by Meredith Mazzilli andMatthew Lewis)
