Washington — Utah Gov. Scott M. Mattheson says his state has decided to oppose mobile basing of the giant new MX intercontinental missile in Utah and Nevada, according to plans proposed by the US Air Force for the Carter administration.
An aide to Mr. Mattheson said that the governor had discussed his position with Gov. Robert F. List of Nevada, and the two governors agreed on their opposition.
The State of Utah, MX project manager Ken Olson in Salt Lake City said by telephone, "could certainly delay the MX by legal action," although alone the state "couldn't stop" the program. "We will continue to work with Congress in efforts to find the best solution," Mr. Olson said.
To meet the growing vulnerability of US Minuteman missiles in fixed vertical silos, President Carter a year ago approved placing 200 of the giant missiles in 4,600 "racetrack"- patterned horizontal shelters in the great basin area of western Utah and eastern Nevada.
The missiles would be shuttled regularly between shelters to fool watching Soviet reconnaissance, thus obliging the Soviets to attack the sites with a huge number of missiles in order to blanket all the launch sites.
The Defense Department decided in early May of this year to substitute a "grid" system of parallel roads for the racetrack system after Utah and Nevada residents, in extensive debates with Air Force and Pentagon officials, made known their concerns. The "racetrack" system, they argued, would adversely effect the two states' land and water resources and natural beauty.
In a long, written rejection of both the "racetrack" and "grid" systems, summed up in a taped, 10-minute briefing, Governor Mattheson suggested instead that the administration might adopt a "quick fix" plan proposed by Prof. William R. Van Cleave of the University of Southern California. The Van Cleave plan is intended to reduce the vulnerability of US ICBMs to Soviet missile attack more swiftly and cheaply than the MX system.
Under Professor Van Cleave's plan, the US would return to earlier plans for a "shell game" with existing Minuteman missiles. Seven hundred of these would be deployed vertically in canister-like containers and shifted between vertical silos.
Utah, said Governor Mattheson, would permit deployment of such modified, Minuteman missiles or vertically launched MX missiles in its territory if necessary. "This would be far less costly a system and far less disruptive of the deployment area."
The vertical silos, Governor Mattheson said, could be deployed on Utah land already under military control and serviced from Hill Air Force Base, thus precluding the taking of additional land from ranchers or nature preserve areas.
Governor Mattheson said a second alternative would use vertical shelters protected by an anti-ballistic missile system. Such a system, prohibited by a Soviet-US 1972 agreement, is again under active discussion in the US defense community.
A third possibility, the governor suggested, was another look at the idea of building small submarines to carry ICBMs in shallow US coastal waters. Both the Pentagon and the US Navy have rejected this concept as impractical from engineering and other viewpoints.
The Utah governor said he had reached his decision to reject MX only "after long soul- searching." He said he had concluded that the Air Force had been "unwilling to share all information about the program candidly" with the people of Utah and Nevada.
Though he agreed with the administration's estimate that the growing accuracy , numbers, and throw-weight of Soviet missiles do endanger US missile systems, the MX system as proposed "appears fatally flawed" because it could not deploy the first 10 missiles until 1986, or the remaining missiles until "the late 1980 s or early 1990s," by which time the Soviet threat might have increased to the extent that MX would be rendered obsolete.
Governor Mattheson said Utah's importance to national security lay not only in the possible basing of missiles there, but because of its efforts to develop independent energy and mineral resources, including coal and beryllium, molybdenum, and other strategic metals.
Utah, he added, "has a finite capacity to bear the burdens and demands" of the huge construction program that MX would require and only a "finite" amount of water and other resources to carry it out. The state's small cities and towns, he said "have limits to their growth. . . . The administration hasn't thought through the total implications, and is simultaneously presenting us with uncoordinated policies."