A study by the congressional Office of Technology Assessment (OTA) concludes that there is no way to base the Air Force's controversial MX missile "without serious risks or drawbacks" but suggests that putting the missiles on small submarines may be the best bet.

In its report, released yesterday, the OTA only analyzes possible ways to base the MX, and makes no recommendation. The thrust of the published conclusions, however, in combination with comments by OTA program manager Peter Sharfman at a press conference yesterday, would suggest that OTA thinks submarines are the safest and most technically feasible solution to the MX basing problem that continues to vex the administration.

The problem with the report is that the study was begun more than a year ago and does not deal directly with some of the new options for MX basing that are now under intensive review within the White House but do not yet have official status.

Nevertheless, the report--a fuller version of a summary published in June--attempts to provide Congress with more up-to-date information that Sharfman said should help legislators "keep the administration honest" when the White House finally says what it intends to do with the huge new missile.

The report makes clear that the administration has a serious problem whatever it decides. If the Soviets continue to expand their missile arsenal, even the 1979 Air Force-Carter administration proposal of 200 MX missiles shuttling among 4,600 protective shelters in Utah and Nevada would be inadequate to protect MX from being wiped out in a first strike. The OTA projected "conservatively" a need for 8,250 shelters by 1990 and 12,500 by 1995 if the Soviet buildup of missiles and warheads continues.

The Reagan administration is considering a scaled-down version of the Carter plan, involving 100 missiles and 1,000 or fewer shelters. The OTA report plus Sharfman's comments make clear, however, that this, too, could be easily overwhelmed even by existing Soviet missile forces, though it would give the United States at least some experience in basing the missiles if the force is expanded later.

If the MX shelters were defended by anti-ballistic missiles (ABMs), it would serve the same purpose as doubling the number of shelters. But here, too, the 1,000-shelter plan said to be under consideration would be far too small, and the report says it is still highly uncertain that an ABM defense would work.

Sharfman pointed out that some pro-MX officials argue that the Soviets would not or could not keep building missiles in the face of a steadily expanding MX program. But the problem with the potential scaled-down Reagan plan, officials say privately, is that it tells Moscow the United States is not committed to a big shelter plan; thus Moscow will probably continue doing whatever is necessary to keep the MX vulnerable to attack.

Basing four MX missiles each on a fleet of 51 diesel-electric-powered submarines poses "no critical technical problems," Sharfman said, nor could OTA identify any technology that promised a breakthrough for the Russians in being able to destroy these submarines at sea. Furthermore, the report claims that submarine-based missiles will be accurate enough in the future to knock out any military target. Using diesel rather than nuclear power would keep costs in line.

And, while submarine basing would delay getting the first MX into service from 1987, with land basing, to perhaps 1989-90, the MX missiles that go in the submarines would immediately become invulnerable. The MX on land would become less vulnerable only when the full shelter system was completed.

Sharfman estimated that 51 MX missile-submarines could be in service by 1994 or sooner. The objections involve political questions of too much reliance on sea-based weapons, different views about what best deters attack, and perhaps some Air Force-Navy problems, he said.