Cleaning up the nation's hazardous wastes will likely cost taxpayers more than $750 billion over the next 30 years if Congress is really serious about the challenge.

Indeed, if Congress wants to return America to pristine conditions, the costs could go as high at $1.2 trillion.That's the word this week from a team of 35 University of Tennessee researchers. The team recently completed the first-ever comprehensive effort to quantify the entire cost for reclaiming the United States from its toxic past.

The price tag on the cleanup is staggering. Just how staggering can be seen from the fact that the $750 million cost is nearly equal to the entire spending by the United States for all environmental programs, including pollution controls, in the 1980s.

But consider the cost of doing nothing. It would mean land left idle or not put to its full potential use because the ground has been poisoned. Idle resources, in turn, mean fewer jobs and less economic growth than would otherwise be possible.

Even delay in doing the cleanup work can be costly. It means higher prices for the cleanup work as inflation takes its toll. And it means a prolonged drain on the public's health because of the various risks to human well-being associated with hazardous waste sites.

Of the total tab for the cleanup work, nearly one-third of the estimated cost - $240 billion - is expected to stem from the Energy Department's cleanup of radioactive and toxic wastes at nuclear weapons production sites. This is an unfortunate legacy left over from the cold war, but it is also a reality that must be resolved.

Other Defense Department hazardous waste sites, including hundreds in Utah, could cost up to $30 billion to rehabilitate. The $30 billion estimate in the study and the military's own recently revised estimate of $24.5 billion, are more than double the estimate made just a few years ago and the military has yet to complete its study of potentially hazardous sites.

Also highlighted in the report was $67 billion to deal with pollution from underground petroleum storage tanks and $30 billion for state and private cleanup programs.

From the removal of radioactive sludge at nuclear weapons plants to cleaning soil around leaking underground tanks at local service stations, it is a problem that affects virtually every American.

Utah cleanup projects have involved the Vitro tailings site in South Salt Lake and the Sharon Steel site in Midvale. Hill Air Force Base has been working with toxic sites on base for several years, including at least one that has affected public water sources.

Since 1980, Congress has appropriated $10 billion for cleaning up the nation's toxic time bomb. Of that money, the Environmental Protection Agency has authorized spending $7.5 billion but has actually expended only $4.8 billion.

The magnitude of the toxic waste problem should put more pressure on deficit-ridden Washington to get out of its lax fiscal habits. Indeed, it's hard to see how Congress and the White House can avoid both deeper spending cuts and higher taxes if this nation is to eliminate the many poisonous garbage dumps that can stunt its growth.