The Washington area's costly and controversial antipollution efforts will almost certainly fail to reduce air pollution enough to comply with federal air-quality standards by the congressionally imposed deadline of 1987, according to government researchers.

"It's looking increasingly bleak," says Austan S. Librach, director of environmental programs for the Metropolitan Washington Council of Governments. A draft COG study indicates that hydrocarbons spewed into Washington's air in 1987 will exceed federal limits by more than 50 million tons a day. Hydrocarbons are a key component of smog.

These findings, being circulated among local officials, could set the stage for renewed debate about regional antipollution measures at a time of widespread uncertainty over the Reagan administration's efforts to overhaul the nation's air pollution laws. The administration favors less stringent requirements than were set by the 1970 Clean Air Act, which is expected to undergo further argument when Congress reconvenes.

Concern was heightened last week by President Reagan's decision not to require federal government employes to pay higher prices for parking. Many regional officials long have urged increased parking fees to deter workers from commuting by car and thus cut automobile pollution.

"Government, more than everybody else, ought to take the leadership," said Venkataraman Ramadass, a key District of Columbia air-quality official. "We consider this increase in fees for employe parking one of the most feasible things to do."

A bill to prohibit free and low-cost parking at major government and private office buildings is pending in D.C. City Council.

Under Clean Air Act provisions, the Washington area could face stiff federal sanctions, including possible cutoff of federal highway and sewer funds, if it fails to meet the 1987 air-quality standards. Some officials contend that efforts should be made to reduce pollution even if the federal rules are weakened.

"From a public health point of view, it certainly matters," says Robert L. Calhoun, vice mayor of Alexandria and chairman of the Washington region's Air Quality Planning Committee. "You ought to worry about that."

Nevertheless, many officials express uncertainty about what further steps to institute. COG environmental chief Librach says that the remaining possibilities may include such extraordinary measures as banning all traffic in parts of the Washington area or prohibiting driving on certain days -- proposals viewed as highly unpalatable politically and unlikely to be adopted.

In addition, Librach noted in an interview last week, regional officials have discussed 59 other possible antipollution steps in an attempt to reach the 1987 goal. But he added: "It looks like those measures would not achieve attainment, even if we were able to institute them all."

He estimated that the 59 proposals might cut hydrocarbons by another 70 tons daily -- to 230 tons, an amount that would still exceed the U.S. standard by 50 tons.

"Only a handful of these 59 proposals will prove to be cost effective, politically acceptable and practical," Librach said. Among the proposals: a ban on free and low-cost parking for federal employes -- precisely what Reagan rejected last week -- and other improbable, short-range plans, such as extending the Metro subway to Dulles International Airport, forcing higher parking fees on private companies' employes and setting still stiffer tests for annual auto-exhaust inspections.

In the Washington area, exhaust from cars, trucks and buses long has been regarded as a major cause of two pollutants: carbon monoxide and smog. Air-quality specialists say this area's carbon monoxide levels probably will be reduced enough to meet federal limits by 1987, except perhaps at a few congested traffic intersections in suburban areas.

The Reagan administration favors several steps to ease antipollution rules, including postponing the 1987 deadline, relaxing urban air-quality standards, and relaxing emissions requirements for auto manufacturers. Controversy is mounting here over mandatory auto-exhaust inspections, which recently started for Northern Virginia motorists and are scheduled to begin in Maryland and the District in 1983.

Maryland, Virginia, and the District are required to submit plans to the Environmental Protection Agency by July 1 to show how they will meet the 1987 standards.

Librach said that the Washington area must reduce its daily hydrocarbon emissions from the 1980 level of 372 tons to 180 tons in 1987 to comply with the federal ozone standard, now set at 0.12 parts per million. But antipollution steps currently considered likely to be implemented will only reduce daily hydrocarbons to about 300 tons, he said.