A proposal backed by Northern Virginia local governments to end binding arbitration of Metro labor contracts ran into critical questioning by Democrats in the Virginia Senate today.

Binding arbitration has been blamed by officials for some of the rise in Metrobus operating costs and deficits that must be paid out of local tax revenues in Northern Virginia. Metrobus deficits currently are costing Northern Virginia taxpayers about $15 million a year.

Sen. Wiley F. Mitchell Jr. (R-Alexandria) and Del. Wyatt B. Durette Jr. (R-Fairfax) have proposed amendments to the Metro compact between Washington, Maryland and Virginia that would eliminate binding arbitration in labor disputes with bus drivers and other Metro employees and bar strikes by them.

At a public hearing before the Senate Privileges and Elections Committee, Sen. Adelard L. Brault (D-Fairfax) told Mitchell and Durrete that Virginia approval of the compact amendment "would be an exercise in futility" unless Maryland and the U.S. Congress agree to it. Congress acts on behalf of the District of Columbia on interstate compacts.

Mitchell urged the committee to take the lead in insisting on the change. "If you charge us with the responsibility of getting advance agreement from the Maryland Assembly and the Congress, then you have sounded the death knell for this proposal," he said.

Attention focused on the arbitration provision last November when a panel ruled that Metro must continue paying full cost-of-living adjustments to bus drivers and other employees. Metro officials had hoped to stop the cost-of-living payments in their efforts to slow the rising operating deficit, expected to reach $54 million for the whole system this year.

As of last Oct. 1, cost-of-living adjustments had accounted for all but 42 cents of the $2.15 increase in hourly wages of bus drivers since the Washington Metropolitan Area Transit Authority (WMATA) began operating the bus lines in 1973.

Durrette and Mitchell told the committee that the average annual wage of drivers has reached $16,842 and total compensation, including fringe benefits, now averages $21,114. "Personnel costs amount to 82 per cent of Metro's total costs," Durrette said, "If the increase in personnel costs since 1971 hads been held to the increase in the cost of living, then the deficit would be 25 per cent lower," he said.

Mitchell told the committee, "When binding arbitration was included in the Metro compact, Metro was being represented as an operation that would pay its own way and require no public funds, but today it is a public agency requiring $54 million a year in operating subsidies."

Walter Bierwagen, vice presient of the Amalgamated Transit Union, and Julian Carper, president of the Virginia AFL-CIO, appeared in opposition to the proposal. Bierwagen said binding arbitration has been a feature of transit contracts in the Washington area since 1935. He called it "the civilized substitute of reason and logic for the tooth and fang law of the jungle."

Mitchell told the committee that the Arlington County Board, the Fairfax County Board of Supervisors and the Northern Virginia Transit Commission had unanimously endorsed the proposal to end binding arbitration.The city councils of Falls Church and Fairfax City also endorsed the proposal and the Alexandria City Council did not oppose it, he said.

Fairfax Board Chairman John F. Herrity testified for the change and told the committee that the only alternative to reducing Metro deficits is withdrawal of Virginia from the Metro compact.

In other legislative action, the State Senate passed without debate two revenue measures affecting Northern Virginia. It approved a bill that would give Arlington permission to impose 5 per cent hotel room tax in 1978 and allowing Fairfax City to impose a [WORD ILLEGIBLE] per cent hotel tax later this year.