Prince George's County Executive Parris Glendening yesterday pushed through a surprise resolution calling for the County Council to reaffirm its support for a north county Green Line Metro route first approved in 1981.

The resolution, narrowly adopted within hours of its introduction and without the customary review by a council committee, was an effort to stave off "the appearance of indecision" that Glendening said was caused by moves to reopen discussions of the issue, a Glendening aide said. But critics of the move said that Glendening was merely trying to close off further debate by opponents.

"We're reaffirming the county's position that we want to proceed as promptly as possible," said John Wesley White, chief administrative officer. White said that Glendening became convinced that he should move quickly because the Metro board will soon be seeking additional federal funds.

Councilman James Herl, who tried to reopen discussions of the Metro route earlier this summer, sharply criticized his colleagues for supporting Glendening and vowed to introduce a counterproposal at the council's meeting next week.

"Those of you who support this can say you pulled one over on Mr. Herl; he didn't know this was coming up," Herl said. "But those of you who come from municipalities, what you're saying is, 'We don't care what you think.' " Herl, a new council member, represents a district with five municipalities, the largest of which is College Park.

Yesterday's dispute concerned the section of the Green Line scheduled to run from Calvert Road in College Park to Prince George's Plaza. Several municipalities in the path of the route--which would ultimately run from Greenbelt though the District of Columbia to the southern end of the county--have continued to oppose the route, saying the rail line would be unsightly, too noisy and too close to their homes.

The municipalities have also disagreed with each other about the best location for an access road, which would have to be built to accommodate automobile traffic displaced by the rail line.

Earlier this summer, after abandoning efforts to move the College Park station altogether, Herl began pressing for the addition of a $15 million underground tunnel to lessen the noise, and advocated an alternate road to the south of the Calvert Road station. Glendening opposed Herl's proposal saying it was too expensive and that it would cause delay in the long-awaited Green Line, now scheduled for completion in 1991.

Glendening's hastily drafted measure was presented to the council mid-morning. The council immediately moved to discuss the issue in secret, saying a lawsuit might be pending, but then reconsidered and met in public. The vote was 5-4 in favor of the resolution.

In other action, the council also introduced a resolution identifying proposed sites for four group homes for the mentally retarded. The county is required by the state government to identify four such sites by Sept. 30.

The sites are in Beltsville, Oakcrest, Suitland and Temple Hills. Community meetings discussing the sites have been set for tonight and Sept. 19.