(Corrects reference to starting pay)
By Erwin Seba
HOUSTON, Jan 31 (Reuters) - Union refinery workers werepreparing to walk off their jobs as early as Sunday while talkswere continuing on Saturday afternoon between labor and oilcompany negotiators in the waning hours of the current nationalpact.
The United Steel workers union (USW) issued notices of apossible strike to several U.S. refineries, which could beginafter the current national contract expires at 12:01 a.m. onSunday, said sources familiar with the notices.
The sources did not know which specific refineries receivedthe notices.
The Exxon Mobil Corp refinery in Beaumont, Texas,received a strike notice on Friday night, according to thecompany. The Beaumont plant was the only Exxon refinery toreceive a notice.
Royal Dutch Shell Plc and Motiva Enterprises refineries have not received strike notices, aspokesman said on Saturday.
Those USW members off from work on Saturday carried outrallies outside negotiation sites and refineries across theUnited States.
Workers were pessimistic an agreement would be reachedbefore the national agreement expires.
"I think the chance of an agreement Saturday night is asgood as a snowball in hell," said one worker, who asked not tobe identified by name.
A Shell spokesman said talks were still underway.
"Negotiations continue with USW with the intent of reachinga mutually satisfactory agreement prior to contract expiration,"said Shell's Ray Fisher.
The current contract covers about 30,000 workers at 63 U.S.refineries accounting for about two-thirds of national refiningcapacity. Not all of those locations could be subject to astrike on Sunday. Only a certain number of plants have contractsthat expire on Sunday.
USW International Vice President Gary Beeves, who isnegotiating on behalf of the union, will decide at whichrefineries strikes will take place after the contract expires,the sources said.
A USW spokeswoman declined to discuss the situation.
A strike notice is legal notification of a possible strikeby a labor union at that location. It does not mean that astrike will take place at that location.
The drop in oil prices since this summer may have cut theunion's ability to win its objectives, said an oil industryanalyst.
"I think the union would have had a lot more leverage sixmonths ago when the price (of oil) was $100 a barrel," saidAndrew Lipow, president of Lipow Oil Associates in Houston. "Butnow, when the industry is facing hard times and layoffs havebeen announced, their bargaining power is limited."
West Texas Intermediate crude delivered at the Cushing,Oklahoma, oil hub finished on Friday at $47.76 a barrel.
Oil prices rose more than 8 percent on Friday due to anattack by Islamic State militants toward the Iraqi oilproduction center of Kirkuk.
Lipow doesn't expect oil or gasoline prices will go up dueto a strike.
"Attacks on Kirkuk will drive up prices, but a strike by theUSW will not," he said.
The USW is seeking annual pay raises double those of thelast agreement. It also wants work that has been given in thepast to non-union contractors to start going to USW members, atighter policy to prevent workplace fatigue, and reductions inmembers' out-of-pocket payments for healthcare.
At least three contract offers have been rejected by USWnegotiators since contract talks began on Jan. 21. The mostrecent rejection was on Friday.
A strike is not expected to affect operations at refinerieswhere workers walk off their jobs, said a refining consultant.
"I am not aware of any examples when refineries have notcontinued operating with replacement workers rather than unionworkers," said David Hackett, president of StillwaterAssociates, an Irvine, California, refining consultancy.
Oil companies have been training temporary replacementworkers since this summer.
The last national refinery workers strike was in 1980 andlasted for three months. (Reporting by Erwin Seba; Editing by Alison Williams, BernardOrr)