The precedent-setting U.S.-Soviet agreement Tuesday allowing dozens of arms inspections on each other's territory annually as part of a treaty eliminating intermediate-range nuclear forces (INF) will permanently change the face of arms control and possibly alter superpower relations, U.S. officials and independent experts said yesterday.

The agreement to be signed here on Dec. 8 by President Reagan and Soviet leader Mikhail Gorbachev calls for an extraordinary exchange of sensitive military information, some of which has already occurred. It also provides for routine or periodic inspection of INF storage, repair and deployment sites, as well as associated missile production and assembly plants in both countries.

These unusual arrangements were needed, American officials said, because for the first time the agreement will eliminate modern weapons that are also small and mobile, and therefore relatively easy to hide, in violation of the treaty. These include about 1,500 Soviet missile warheads deployed since 1977 and 364 U.S. missile warheads deployed since 1983.

No similar provisions exist in past U.S.-Soviet arms agreements, U.S. officials said, so they plan to form a specially trained group of 200 to 300 inspectors, who would be on call to inspect suspected treaty violations in the Soviet Union at a moment's notice. They also may be stationed for months at a time in Votkinsk, a city 600 miles east of Moscow, where SS20 missiles covered by the agreement were once assembled.

A group of Soviet inspectors will similarly be stationed outside a former Pershing II production plant in Magna, Utah, an unincorporated town of about 22,000 people 15 miles west of Salt Lake City, the officials said. The region has previously been off-limits to Soviet visitors, although a delegation of chemical weapons experts was allowed to visit Tooele, 25 miles southwest, for the first time last week.

The inspections go "far beyond anything that's ever been attempted before," Secretary of State George P. Shultz remarked in Moscow after details were worked out Tuesday. Defense Secretary Frank C. Carlucci similarly described them as "mind-boggling."

These judgments were echoed yesterday by independent experts who noted that Soviet willingness to accept such inspections represents a radical departure from past secrecy and paranoia.

"If somebody had asked me about this 10 years ago, I would have said it's wildly improbable," said Harold Brown, defense secretary in the Carter administration.

Richard Pipes, a Harvard professor and Soviet scholar who served on the National Security Council staff from 1981 to 1982, said, "I thought on-site inspection was something they would resist to the last moment, and I still find it hard to believe."

To implement the agreement, the two sides have agreed to exchange long lists of information covering the number and precise location of stored and deployed INF weapons. In agreeing on dismantling procedures, both sides also have revealed fresh details about the capabilities of the weapons, officials said.

U.S. officials said the significance of the data exchange, which began several weeks ago and has been proceeding slowly because of Soviet reticence, was demonstrated when a Soviet negotiator remarked that he "would have been shot" for treason if he had provided the information one month earlier.

On the U.S. side, the Reagan administration agreed to allow continuous Soviet monitoring of the Hercules plant in Utah for 13 years despite scattered fears in the intelligence community and among some administration conservatives that some sensitive technologies might ultimately be revealed.

The plant produces key parts of the nation's long-range nuclear missile arsenal, including the third stage of the Air Force's MX missile. It also is helping develop the Trident II submarine-launched missile and the third stage of the Midgetman mobile land-based missile, which together form the heart of the administration's nuclear force modernization program.

U.S. officials said details of these efforts will be largely hidden from Soviet inspectors of the former Pershing II production building there. But they acknowledged the degree of access to a sensitive U.S. military site would be unprecedented.

"There have been no Soviet visitors to Magna, to my knowledge," said Laura McDermaid, president of the Magna Community Council. "But I think the community will react favorably because {the visit} is related to an issue that everyone is concerned about."

Rep. Les Aspin (D-Wis.), chairman of the House Armed Services Committee, said the agreement will probably "serve as a model for future arms treaties."

"It's a very significant change in the way we're doing treaty verification," Aspin said. Pipes agreed that it could have "a profoundly positive effect on U.S.-Soviet relations, to the extent that things are opening up . . . . It is certainly a giant step forward."

However, several officials noted that the precedent entailed risks.

"Here we have an agreement in which both sides are eliminating whole categories of weapons, which supposedly simplifies verification because there's nothing left to count," said a State Department official, who asked anonymity.

An agreement on long-range strategic nuclear weapons now being negotiated in Geneva will instead limit weapons to an agreed number, theoretically increasing the chance of cheating because both sides will retain some associated production, assembly, and support facilities. As a result, such an accord could "require on-site verification provisions that go way beyond those in the INF treaty," said the State Department official.

Brown said, "I hope we haven't trapped ourselves into something without thinking about it. It is interesting and different, but there are possibilities for both good and ill."

Within certain limited categories of weapons, Brown said, "it will certainly give us a better idea of {their} military's potency, readiness, and capabilities. But there is also room for friction" over carrying out the inspections.

The House Permanent Select Committee on Intelligence, in a detailed report of U.S. verification capabilities, last week cautioned that on-site inspections at a moment's notice -- such as those provided for in the INF treaty -- "are inherently susceptible to being impeded" by the country in which a suspected violation has occurred.

"Therefore, such on-site inspection should not be regarded as a panacea for shortfalls in the capabilities" of more traditional verification techniques, such as spy satellite reconnaissance and eavesdropping, the report said.