The Army expects to miss an April 1997 deadline for destroying chemical weapons even though the Bush administration says disposal of the arms will begin ahead of schedule, according to a report released yesterday.

The General Accounting Office said in the report that the Army's disposal program has encountered several obstacles, including environmental limitations, community opposition and a shortfall in funds.

The investigative arm of Congress found also that the projected cost of destroying the weapons has doubled from a preliminary estimate of $1.7 billion to $3.4 billion and likely will exceed the latest figure.

"Since current construction, equipment and personnel requirements have continued to rise, total program costs will increase even more," the GAO report said.

The agency attributed the cost increases to incomplete information the Army used in its preliminary estimate and program changes to ensure safety.

The Army said it had not reviewed the GAO report and had no immediate comment.

The report was issued less than two weeks after a U.S.-Soviet agreement to reduce superpower chemical weapon stockpiles and the administration's announcement that it would begin destroying the weapons by the end of this year.

Administration officials said the target date for the program is well ahead of the schedule set in the accord signed by President Bush and Soviet President Mikhail Gorbachev during their Washington summit, which ended June 3.

That pact requires each side to reduce its stockpile to 5,000 tons by 2002, although the Soviets have no active facility for destroying their weapons.

The United States and Soviet Union hold the world's largest supplies of chemical weapons, which can blister the skin or disturb the nervous system. The United States says it has about 25,000 tons of chemical agents; the Soviet Union says it has 50,000 tons.

Destruction of the arms is supposed to begin by Dec. 31, 1992.