Metro will have to raise the salaries of its bus drivers and train operators this Sunday twice as much as it had expected because of runaway inflation and an increasingly controversial labor agreement.

The pay increase, required by contract to match the rate of inflation every three months, will give a bus driver 26 cents more per hour than he or she now receives and will add $680,000 to Metro's budget deficit for the current year, General Manager Richard S. Page said yesterday.

The added budget deficit means that local governments will have to dig down deeper to meet the Metro payroll -- always a serious political problem. Already yesterday, a number of local government leaders voiced concern about the inflation-matching increases.

The new pay rate of $9.86 per hour for a fully experienced bus drive or train operator means that he or she will make a minimum annually of $20,508 -- more than many school teachers, firemen and police officers in the Washington area. That fact is adding to local government impatience with the Metro budget.

General Manager Richard Page also told the board yesterday that the proposed budget of $275.8 million for the next fiscal year would have to be increased $2.2 million because of the unexpectely high salary adjustment.

That proposed budget which is balanced by $126.4 million in subsidies from local governments, in undergoing stringent review by local governments. The major factor in Metro' rapidly escalating budgets has been a controversial clause in its labor contract. That cause provides that Metro's transit union employes are protected from inflation every quarter. If inflation increases 18 percent, so does the bus drivers' salary.

"I just don't see how we can have rates like this," Alexandria Mayor Charles Beatley said yesterday. "Our other city employes don't have them, and Metro employes are just as much Alexandria employes as those who work at City Hall."

Joseph Alexander, Fairfax County board member, said that "the local jurisdictions just can't continue to openend fund these kind of wage increases."

Page said he shared the board's concern. Quarterly cost-of-living adjustments, he said, were "generous when inflation was 6 or 7 percent; difficult when it was 13 percent, and impossible when it is 18 percent."

Cleatus Barnett, Montgomery County board member, said, "The question is whether some isolated segment of siciety should be protected from inflation while nobody else is."

Transit union officials have argued for years that there is no reason their employes should be expected to absorb the costs of inflation just because they are public employes.

The 26-cent increase is computed from the D.C. Consumer Price Index for urban wage earners and clerical workers. That index, released last week by the Bureau of Labor Statistics, showed a 2.8 percent increase from November to January. Over a year, bureau officials said yesterday, the inflation rate would be 17.9 percent. Metro's current budget assumed about an 8 percent inflation rate; its budget for 1981 assumes a 10 percent rate.

Page said that the cost-of-living clause will be "the preeminent issue" in negotiations that have just begun with the transit union. Metro's contract with the union expires April 30.

Protection of the cost-of-living clause was a central issue in the wildcat eight-day transit strike here in July 1978 that crippled the city.

Metro is required by Congress to submit all unresolved labor issues to arbitration. Arbitration panels consistently have upheld the cost-of-living escalator in the contract.

There also was bad news about Metro's subway construction operation yesterday.

The board approved changes to construction contracts at two Metro stations where mistakes have been made.

It will cost about $1 million to fix the Eisenhower Avenue station in Alexandria on the unopened extenstion of the Blue line from National Airport.

Metro's mistake, asssistant general manager John Egbert said, came in not heeding the warning of a designer that only one highly specialized construction technique would work for the station as proposed. Metro did not require that technique in its specifications for the $28.9 million station. As construction progressed and it became obvious the technique would have to be employed, about $1 million in added costs resulted. "It was our fault," Egbert said.

The other mistake is visible along Rockville Pike at the $19.6 million Grosvenor station, just outside the Beltway. The roof of that station has been supported for months now by heavy timbers because it is feared it will fall down without them.

Metro blames that embarrassment, first reported by The washington Post, on the design. It will cost "less than $500,000" to fix, Egbert said, and Metro is seeking reimbursement from the designer. Buchart-Horn Inc. of York, Pa. did the design work on the station for $931,0009