The on-site inspections provided for in the INF treaty to be signed at next week's summit meeting are "mind-boggling," to quote Secretary of Defense Frank Carlucci. With American inspectors in Siberia and Soviet inspectors in Utah, the historically suspicious U.S.-Soviet relationship may never be the same again. The Reagan administration deserves the utmost praise for negotiating such far-reaching measures.

However, the verification provisions are not what Frank Gaffney terms "novel" and "undreamed of by the framers of the flawed SALT II accord" {"Take a 'Timeout' on the INF Treaty," op-ed, Nov. 30}. The Soviet veil of secrecy has not lifted for the first time with the negotiation of the INF treaty. On the contrary, over the past 15 years there has been a steady erosion of Soviet secretiveness; the current Soviet willingness to permit intrusive inspection is just another step, albeit a giant one, in the recent trend.

The final sticking point in the INF treaty negotiations seems to be the Soviet delay in handing over, as agreed, a detailed list of their forces to be destroyed. Secretary of State George Shultz has said, "We must have that data."

When we began negotiating the SALT II treaty in 1972, the Soviets had never provided the United States with such a listing. The SALT I Interim Agreement was signed without it, the Soviet attitude being that the information was theirs to know and the United States' to find out. During the SALT II negotiations, the Soviets consistently rebuffed our insistence that they reverse this policy.

Then, in 1978, the chief Soviet negotiator, Vladimir Semenov, orally advised me of the exact number of heavy bombers possessed by his nation, commenting that he had just "violated" 400 years of Russian history. Over the ensuing 18 months, the Soviet negotiators continued to add to this information with the result being that the SALT II treaty was signed with a fully agreed-upon data base listing both countries' weapons to be limited.

In the corresponding Comprehensive Test Ban negotiations, the Soviet Union agreed in principle that the United States and Great Britain be permitted to emplace up to 10 unmanned seismic stations on Soviet soil to monitor nuclear testing in that country (in return for reciprocal Soviet privileges). These negotiations were suspended after the Soviet invasion of Afghanistan, but an important principle, intrusive inspection, had been established.

In addition, an often-neglected document was signed by President Carter and Soviet Premier Brezhnev at Vienna in 1979: the third part of SALT II, intended to set the course for SALT III negotiations. This statement included the following language:

"Further limitations and reductions of strategic arms must be subject to adequate verification by national technical means, using additionally, as appropriate, cooperative measures contributing to the effectiveness of verification by national technical means" (emphasis added).

It had come to be understood that these "cooperative measures" would include on-site inspection. In fact, in the days following agreement on this language, American and Soviet representatives actually began discussing the possibility of specific cooperative measures to facilitate confidence in monitoring. These discussions, unfortunately, terminated with the withdrawal of the SALT II treaty from Senate consideration.

Next week, President Reagan will sign an arms control treaty, which will provide for intrusive on-site inspections -- a giant step for superpower confidence-building, but one not without history.

-- Ralph Earle II The writer, who served as chief U.S. negotiator of the SALT II treaty from 1978 to 1980, is national policy director of the Lawyers Alliance for Nuclear Arms Control.