Though congressional and presidential investigators have barely started their separate probes of the Alaskan oil spill, already they're being swamped with plenty of suggestions for averting a repetition of this fiasco.

The suggestions range from the imposition of a stiff gasoline tax as a means of curtailing the demand for oil, to requiring that oil tankers be equipped with double bottoms as are most other merchant vessels.But before rushing to embrace new reforms, Washington should look for ways to strengthen existing safeguards that broke down.

The most obvious lapse was Exxon's employment of a known problem drinker to command the ship that ran aground. He is said to have been asleep in his stateroom, leaving on the bridge a third mate who was unqualified to steer the ship.

Another lapse took place in 1981 when Alyeska, the consortium that built the Alaska oil pipeline and runs the shipping terminal at Valdez, abandoned an around-the-clock emergency team to deal with oil spills. The reason for the cutback - to cut costs. Some economy measure.

Still another lapse came when it took 35 hours to surround the grounded oil tanker with barrier booms designed to contain spilled oil. By then, the spilled oil was far from the ship. Under a plan for containing oil spills in Prince William Sound, barrier booms were supposed to be placed around a stricken vessel within just five hours.

The list goes on and on. Chemical dispersants were supposed to have been tested on the floating oil immediately, but this wasn't done for many hours. Though the tanker spilled 240,000 barrels of oil into the sea, Alyeska and Exxon reportedly had on hand only enough dispersant for a 6,500-barrel spill. Fishing boats that were supposed to be quickly deployed to help contain the spill weren't summoned for days. Some of Alyeska's and Exxon's radios were not powerful enough to reach all the vessels involved.

The lesson should be clear: Private industry can't always be relied upon to guard against oil spills but must be policed by the government much more closely than Washington has been doing.

Still another lesson is that someone needs to police the federal agencies assigned to do such policing. The grounded tanker might have been kept from straying into dangerous waters if the Coast Guard's tracking system had not been replaced with less effective equipment as a cost-cutting measure.

In the Alaskan oil spill, then, there's plenty of blame to go around - and plenty of repair work to be done on existing safeguards before new ones are undertaken.