Massive Radioactive Discharges Detailed

More than 120 million gallons of liquid radioactive waste was intentionally discharged into the ground at the Hanford nuclear reservation from 1946 to 1966, a new federal study says.

The Energy Department report, released Friday, combines for the first time known data on radioactive releases from the huge reservation where plutonium was once produced for nuclear weapons.

“There is not a safety hazard to the public from this material, as long as we pay attention to it,” said Phil Hamric, deputy Hanford manager.

State and federal regulators agreed that there were few surprises in the report, which combined data that has been publicly available for years.

But they said just having the highly complex and widely scattered materials combined in one report would help in the decades-long cleanup of the nation’s most polluted defense production site.

A total of 678,000 curies of radioactivity leaked into the ground at Hanford, nearly all of it in the reservation’s waste storage area, the report said. Two-thirds of that was radioactive tritium.

But 99.9% of the radioactivity initially put inside the giant storage tanks remained there, officials said.

The report also said solid radioactive waste containing 4.8 million curies was buried at the site, about 120 miles southwest of Spokane.

The report said some liquid waste seeped into ground water below the site and had reached the Columbia River.

But Hanford officials said the waste dispersed so quickly it was well below drinking water standards by the time it reached the water intakes for communities downstream.

Ralph Patt, a Hanford regulator for Oregon, disputed that conclusion. He said it was impossible to know how much radioactivity was still trapped in ground water plumes heading toward the river.

“Until we know more we can’t predict the consequences to the river,” Patt said.

The report also said leaks from storage tanks and other accidental spills sent 750,000 gallons into the soil. That does not include 50,000 to 800,000 gallons that may have leaked from a single tank that is still under investigation. Water has been repeatedly added to this tank to keep internal temperatures down, despite the leak.

The intentional waste discharges to the ground were to so-called “cribs,” designed to filter out the radioactivity before it reached ground water. This occurred mostly in the 1940s and 1950s, although some is still being used today, officials said.

Hamric said poor record-keeping in the past prevented the Energy Department from knowing exactly how much waste and which chemicals were spilled into the ground. He said some of the radioactivity may survive for 100,000 years.