Volpe: Ooze not imminent danger
By Joe Walker
A radioactive, black, tarlike material found oozing from federal land behind the Paducah Gaseous Diffusion Plant in July is not imminently dangerous to people living near the plant, says the head of Kentucky's Radiation Control Branch.
"This material was buried, and as long as it is covered, it doesn't represent a threat to health and safety," said Dr. John Volpe.
Plant contractors noticed the oozing substance July 15 in one of the tracks left by their drilling truck. They were preparing to install monitoring wells to look for radioactive substances in groundwater near a plant landfill, closed in 1996, that is on Department of Energy land just north of the plant fence.
Although the site - about 36 square feet - is near the landfill, testing done so far suggests that the substance is not coming from the landfill, said DOE Paducah Site Manager Jimmie Hodges.
"We did another hole punch in the soil about 60 feet away and didn't encounter this material," he said. "We also monitor leachate - water that runs through the landfill - and we don't see any elevated levels like that found at the site."
Since discovering the problem and consulting the state, the plant has covered the area with plastic, soil and straw, surrounded it with rope and posted warning signs.
Hodges said DOE knew about the site because it was a dumping ground for debris from plant construction starting in 1950, long before there was a landfill. The dump site was scheduled to be cleaned up but had a much lower priority than contaminated groundwater, the plant's chief environmental concern, he said.
"This really wasn't a surprise area. We knew it existed. There was just a question of what was in there," Hodges said. "The basic surprise was that we had radioactive material."
He said contractors found no elevated radiation in initial tests, but he asked them to repeat the process about three weeks later. Workers dug up some of the material, which looked like pieces of tar paper and asphalt shingles. Secondary testing revealed elevated levels of uranium and technetium-99, both of which are radioactive, Hodges said.
Volpe said the plant faxed him preliminary test data Aug. 12 and followed Aug. 20 with a letter to the Cabinet for Natural Resources documenting the problem. A review of the data suggests that although the uranium levels are higher than expected, they are still consistent with natural uranium found in soil, he said.
Uranium hexafluoride, a man-made compound, is used by the plant in huge amounts to make fuel for nuclear reactors.
Technetium is not natural and is a signature of past plant practices. It came into the plant as a byproduct of nuclear fuel rods, which the plant processed from the early 1950s to the mid 1970s.
"I'm trying to sit down and run risk calculations," Volpe said. "But if this material was covered with soil, I don't feel it would pose a risk. That's my initial impression."
Volpe said tests showed no evidence of plutonium, similar to technetium. In June, three plant workers and an environmental activist group sued former plant contractor Lockheed Martin. Among the allegations is that workers were exposed to plutonium and that contaminated materials were secretly dumped in the landfill, which was not permitted to accept radioactive or hazardous waste.
Technetium and trichloroethylene, a common cleaning solvent, are considered the two leading plant contaminants, mainly because they are in groundwater. DOE keeps pumping and treating groundwater while looking for a more reliable treatment process. It also has replaced about 90 residential wells with city water to eliminate the groundwater threat.
Elevated levels of uranium and technetium have been found in sediment, primarily in a ditch on plant property that for many years was a discharge point for treated wastewater. Hodges said the site where the black ooze was found is near a forerunner of theditch that was filled in many years ago. It was replaced with a new diversion ditch, just west of the old one, to make room for the landfill, he said.
"That may be another reason the radiation found at the dump site shouldn't be quite so surprising," he said.
Hodges said records are sketchy on how long the area was a dump site. He said DOE has no information to support claims in the lawsuit that the materials were illegally dumped in the landfill.
Mark York, spokesman for the Natural Resources Cabinet, said DOE will submit plans for final cleanup of the dump site, as well as information on the source of the contamination and how it came to be dumped there.
"We are taking it seriously because it is radioactive
material," York said.