THE FUTURE of nuclear power has long been clouded by the question of where and how to store radioactive waste and spent nuclear fuel. There may come a day--perhaps as soon as 1986-- when the limited, short-term storage facilities adjacent to some power plants fill up. Then what? Will existing plants have to curb operations?

Recent California laws effectively ban new plants in that state until the federal government fulfills its longstanding commitment to find a national solution to disposal of nuclear material, whether by burying it in underground salt domes, burrowing into granite formations or sticking the stuff into Nevada's volcanic tuff. On their face, the California laws are designed to prevent further reliance on an uncertain energy source. But the argument sounds a bit like a subterfuge by nuclear power opponents. And if other states follow, it would slow nuclear development even further, if that's possible. The Supreme Court will soon decide whether California's cautious planning illegally interferes with the national effort to promote and regulate nuclear power.

In December, Congress enacted the Nuclear Waste Policy Act of 1982, which provides a scheme for interim storage of radioactive waste and an elaborate road map for reaching a long-delayed federal decision on permanent disposal facilities, to open for business by the late 1990s. This legislation, difficult years in the making and certainly cause for hope, hardly represents a solution. The interim storage capacity is so small that it will only handle the load if existing plants agressively build additional storage space and share underused storage capacity at other facilities. Those stopgap measures will surely raise the same kind of local political and environmental objections that traditionally go with the effort to develop nuclear power. And for the longer run, while the careful timetable of feasibility studies, site comparisons and environmental "assessments" sounds reasonable enough, it is a close schedule that could easily slip considerably.

The statute cleverly does away with the need for a controversial appropriation down the road by charging utilities now for the storage capacity they will get near the turn of the century. But the government's ultimate choice of permanent storage sites will surely trigger political shock waves: just look at the delays in deciding where to put garbage dumps, prisons and MX missiles.

Nuclear power development should be an important part of our energy future. Some areas of concern, such as plant safety or the transportation of radioactive materials, are best left almost exclusively to federal authorities. Local governments, for example, should not be able to override federal regulations and ban shipment of radioactive materials through their jurisdictions--another case now in federal court. The federal government's promises about waste storage, however, are to an extent only elaborate road maps, and they should mature into concrete action before either courts or Congress instruct states to abandon cautious planning. For now, California's approach is within the range of reason. If the next few years go well, the same restraint will be unnecessary.