Flood Officials See Lingering Environmental Damage : Cleanup: People are being exposed to raw sewage, toxic wastes and hazardous chemicals. Receding water will create new problems, experts say.

The Great Flood of ’93 is clearly causing major environmental damage in the Mississippi and Missouri river basins, prompting several dozen federal, state and local officials to begin planning Wednesday for hazardous conditions as floodwaters recede.

Officials from the federal Environmental Protection Agency, the U.S. Army Corps of Engineers, the Federal Emergency Management Agency and the U.S. Geological Survey, meeting with state and local authorities, said they hope that the massive volume of floodwater will dilute the polluting effects of sewage, agricultural chemicals and other glop that is finding its way into the rivers.

But they know that even so great a volume of water will not likely wash itself clean. For example, water-quality monitoring stations are showing big increases in at least one pollutant, especially as the waters concentrate in the lower Mississippi Valley.

“The initial indications do show an increase in the nutrient levels in the lower Mississippi and the Gulf of Mexico, and we are doing analysis now to determine the actual extent,” said Tim Tomastik, a spokesman for the National Oceanic and Atmospheric Administration in Washington. Nutrient levels generally reflect increased fertilizer runoff.

Pushed by rising water tables, underground fuel tanks have sprung out of the ground and leaked into the water. Drums of hazardous industrial wastes have been carried away by the water. Rushing water has claimed not only households but all of the hazardous products designed to keep them cleaned and oiled, ranging from drain cleaners to household insecticides to paint thinners.

Many farmers have lost drums of fertilizers and pesticides. Abandoned farm and recreational vehicles sunk under the water contain batteries that hold dangerous sulfuric acid, which is virtually certain to leak.

In the Kansas City area alone, raw sewage is being flushed directly into the river from at least a dozen communities whose water pumps or waste-water treatment plants have been flooded. In all, local reports indicate that about 26 plants in the Missouri River Valley are spilling raw sewage into the river.

And when flood victims return to their homes, they will pull mountains of rubbish from the ruins, which will create huge disposal problems.

In response, Missouri and Iowa already have relaxed many regulations against the controlled open-burning of wastes. Officials here said that before allowing such burning, they sought advice from federal and Florida state officials who oversaw the cleanup following Hurricane Andrew, which generated a massive volume of rubbish.

The EPA will provide technical assistance to such efforts and will monitor air quality in the areas surrounding such fires, according to spokeswoman Rowena Michaels.

In Des Moines, officials have already begun to collect hazardous household chemicals, urging flood victims to hand over their sodden and rusted cans of cleaners, spot removers, lubricants and paint products.

As floodwaters begin to recede elsewhere in the Midwest, EPA inspectors are fanning out to inspect as many as 415 sites where hazardous materials and waste water are stored or treated.

Their findings, said EPA Regional Director William Rice, will be the agency’s first key measure of the size of its task.

“We’re looking at months just to respond to cleanup issues,” Rice said. “The job of getting back to a more routine environmental program is going to be complicated.”

The proliferation of environmental laws will be one of the key complications in cleaning up after the disaster, experts said.

When the last great flood swallowed fields and communities throughout the Midwest in 1951, the EPA didn’t exist and there were few environmental laws and regulations. As a result, Rice said, much of the environmental response to the flooding is a first-ever effort.

At least one dangerously polluted site, Rice said, appears to have kept its hazardous contents corralled in spite of an onslaught of water. Kansas City Structural Steel in Kansas City, Kan., was partially flooded early last week, prompting deep concern in the neighboring urban community of Armourdale.

Citizens there said they feared that sewer backups would expose them to toxic runoff from the plant’s idled smelter. Rice said initial measurements indicated that none of the plant’s toxic waste has leaked into the water, but he added that samples would continue to be taken from nearby yards and day-care centers.

The Armourdale area, threatened on three sides by the Kansas River, provides a dramatic example of the environmental dangers that flooding can bring. In addition to Kansas City Structural Steel, Armourdale is home to several firms that produce and store hazardous materials.

Rice said the results of the EPA’s monitoring efforts will likely affect a host of decisions, including the siting of future hazardous materials plants. For now, he said, officials can only urge people to steer clear of the floodwaters while they measure the rivers’ ability to absorb the mounting environmental hazards.

The difficulty of planning beyond a crisis while it is still playing itself out was underscored Tuesday when the federal-state-local planning group had to evacuate its original meeting site in Kansas City, Kan. as the floodwaters threatened to overwhelm the city’s levees. By Wednesday, however, the group had moved to higher ground.