Most U.S. military personnel stationed in El Salvador are drawing $65 monthly in special "hostile fire pay" although their chiefs in the Pentagon argue that their jobs are not hazardous enough to require reports to Congress under the War Powers Act or other laws, according to a report released yesterday.

The report by Comptroller General Charles A. Bowsher disclosed that a blanket designation of El Salvador as a "hostile fire area" was recommended by the commander of the U.S. military group there in August, 1980, and endorsed by regional commanders and several layers of Pentagon officials in the latter days of the Carter administration.

In April, 1981, however, a tentative Pentagon ruling that El Salvador qualified as a hostile fire zone was reversed for "policy reasons," evidently to avoid the necessity of reporting to Congress that U.S. forces had been introduced into hostile situations.

Nevertheless, General Accounting Office studies disclosed that "most military personnel in El Salvador were receiving hostile fire pay most of the time." Worldwide last year, according to the report, 129 Army personnel were receiving "hostile fire pay," and 115 of them were stationed in El Salvador.

In order to receive the extra $65, a U.S. soldier typically signs a statement monthly that "I was subjected to hostile fire" as defined in regulations, and the approving officer certifies that the soldier "was subjected to small arms fire or he was close enough to the trajectory, point of impact or explosion of hostile ordnance so that he was in danger of being wounded, injured or killed."

Bowsher reported, "The overall extent and continuous nature of these payments indicates that the Department of Defense virtually treats El Salvador as a hostile fire area."

The GAO report, requested by Sen. Edward Zorinsky (D-Neb.), also described logistical maneuvering by the Pentagon to avoid reporting to Congress under the War Powers Act that U.S. personnel were introduced into El Salvador on armed helicopters "equipped for combat."

According to the GAO, the M60 machine guns on Huey helicopters provided to El Salvador were removed from their mounts and shipped separately so that the helicopters entered Salvadoran airspace "unarmed." Once in the country, the machine guns were mounted by a U.S. Army team before the helicopters were transferred to Salvadoran authorities.