Washington — San Diego is home to some of the most sensitive United States defense installations. Weapons plants line the roads near the waterfront airport. Across the bay are the aircraft carriers and billion-dollar Aegis cruisers of a giant Navy base. The area is so rich in military secrets that Soviet diplomats are not allowed into the surrounding county. But if the US and the Soviet Union sign a pact limiting intermediate-range nuclear forces (INF), San Diego could be open to Soviet visitors with powerful binoculars.
One downtown plant is a General Dynamics factory that produces ground-launched cruise missiles, a US intermediate nuclear weapon. The sanctioned spies would be inspectors making sure no new cruise missiles were produced.
US officials are insisting that any INF treaty provide for such on-site checks. While they say this provision would be necessary to ensure Soviet compliance, they admit to anxiety about the corresponding intrusions in the US.
``You're talking about 100 Soviets in this country and presumably the same number of us over there,'' said Kenneth Adelman, Arms Control and Disarmament Agency director, last week.
Soviet negotiators have accepted the principle of on-site verification, according to US negotiators. It remains to be seen if both sides can agree on details.
The US proposal on INF calls for each side to send inspectors to final assembly and deployment areas for intermediate nuclear weapons.
For the US weapons - the Pershing 2 and cruise missiles - these areas are in military bases in Western Europe.
In addition, the US wants electronic monitoring and on-site inspections at intermediate-missile factories.
Though inspectors might not be allowed inside buildings, they would at least be able to scrutinize exteriors and production compounds. This would allow the Pentagon an unprecedented peek at Soviet facilities, and vice versa.
It is far from clear how many factories and storage areas in the US would be affected. The key General Dynamics plant in San Diego would probably be at the top of the Soviet Union's list, as would a McDonnell Douglas cruise missile factory in Titusville, Fla., and the Martin Marietta Pershing 2 facility in Orlando, Fla.
Scrutiny might even extend down to subcontractors, such as Atlantic Research Corporation, which produces the Pershing 2's solid-fuel rocket booster.
The companies in question may not yet have realized what the INF negotiations mean for them.
The Washington representative of one contractor that would be subject to Soviet inspection was dumbfounded when the implications of on-site verification were explained to him. ``I can't believe they'd let the Soviets do that,'' he said.
There is some question whether the US government has the authority to allow inspection of facilities that are private property.
If an INF treaty is signed, Congress may need to pass a law mandating on-site inspection at contractor plants.
Absent a voluntary contractor agreement, on-site inspection ``may very well require legislation,'' said Sen. Dale Bumpers (D) of Arkansas on television Sunday.
Reagan officials say the US would benefit from an on-site inspection regime. The Soviet Union is such a closed society that the US would have to actuallly peer in factories to ensure INF treaty compliance, this argument goes, while the US is so open that the Soviets would not learn much that they do not already know.
Some outside analysts, however, do not feel that the benefits of on-site inspection are so evident. ``Even with such intrusion you could not have absolute confidence the Soviets were complying,'' says Michael Krepon, a verification expert at the Carnegie Endowment for International Peace.
The extreme nature of Soviet secrecy underlies Mr. Krepon's reasoning. Even if US inspectors were allowed to inspect Soviet intermediate-missile plants, Krepon asks, would they really believe the Soviets were not building a clandestine plant somewhere, just in case?
The US might remain anxious, while Soviet intelligence collection would have been made easier. ``Is it in our interests to have Soviets crawling around our most sensitive production facilities?'' Krepon asks.
The Carnegie analyst makes his point not to oppose an INF treaty, but to say that verification provisions should be thought out more carefully. INF reductions could perhaps be verified by continued reliance on spy satellites, with more limited, occasional on-site checks of suspected violations.