Radioactive VY shipment lands in Pennsylvania

By Kathryn Casa | Vermont Guardian

Posted September 6, 2006

Editor’s note: This is a revised and corrected version of a story posted earlier this morning.

BRATTLEBORO — A container shipped from Vermont Yankee on Aug. 31 ended up at its destination later that night with radiation readings four times higher than those allowable under federal law, according to a report filed Sept. 1 with the Nuclear Regulatory Commission (NRC).

The shipment — a box measuring 6x7x8 feet containing a machine used to cut and crush control rods, the devices inserted between fuel rods in the reactor to control the fission process — registered no more than 60 millirem per hour before it left Vermont, according to Vermont Yankee (VY) records. That level is well below the federal Department of Transportation’s (DOT) 200 millirem hourly contact exposure limit.

However, when it arrived at the Susquehanna reactor in Berwick, PA, the bottom of the container registered 820 millirem per hour, more than four times the DOT limit.

The container was shipped on a flatbed truck by a private contractor — Hittman Transport Services of Barnwell, SC. As of Tuesday the container remained closed in a controlled area at the Susquehanna plant, while inspectors made special preparations before opening it, according to NRC spokesman Neil Sheehan.

He said they planned to open the container Wednesday.

En route to its destination, the truck stopped at rest stops on the westbound side of the Massachusetts Turnpike and on southbound Interstate 87 after existing Interstate 90, according to an incident report filed by Susquehanna officials, who were required to make a report to the NRC because of the high radiation recording.

“No one to the knowledge of the driver came in contact with the shipment,” the report states. The truck arrived at Susquehanna at 8:45 p.m. and the driver, who was wearing a radiation detection monitor, slept in the vehicle. Sheehan said the driver’s dosimeter showed readings well within acceptable levels.

A spokeswoman for the trucking company said she had no knowledge of the incident.

According to the NRC report, the shipment was formally received at the Susquehanna facility at 8:05 a.m. the next morning. The high reading was recorded at 11:15 a.m., and Susquehanna officials notified the NRC at 12:15 p.m.

The shipment showed no signs of surface contamination, the report declared, and it exceeded the dose rate limit only on the bottom of the container once it was lifted off the truck. “Doses under the trailer prior to lifting the shipment did not exceed the limit," the report states.

“Unless someone got right up under it, the probability that someone would have received any kind of exposure from that configuration is low,” said Deputy Regional Administrator Marc Dapas.

VY spokesman Rob Williams also emphasized that despite the unexplained high radiation levels, the shipment represented no threat to public health and safety in transit because the radioactive side was against the bed of the truck, which provided additional protection, he said.

“At no time during the shipment was there any additional exposure to anyone because the flatbed truck provided adequate shielding,” Williams said. “In fact, the radiation level in question was detected only at the bottom of the package, and only after it was lifted off the flatbed, so this had no impact on public health and safety.”

Vermont Yankee is responsible for shipments while in transit, Williams noted. Two experts from VY’s radiological shipping group had left for Pennsylvania to determine what may have caused the increase, he said Tuesday.

“We’ve reviewed our radiological survey and confirmed that the package left here in compliance,” Williams noted.

Sheehan speculated the increase might have been due to the machine shifting during transit, resulting in a part with higher contamination levels closer to the bottom of the box. Or, he said, a piece of debris from the VY spent fuel pool could still have been attached to it.

The tool is what Sheehan called a cutter-shearer machine that crushes control rods in order to ship them more easily. Control rods are used to separate spent fuel rods in the reactor. They are inserted between the fuel rods in crucifix form, with a centerpiece and four blades inserted between the fuel bundles, and later stored in the plant’s spent fuel pool, Sheehan said.

He said reactor operators periodically install new control rods and remove old rods from the fuel pool.

Anti-nuclear activist Ray Shadis, technical advisor to the Brattleboro-based New England Coalition, speculated that the discrepancy in radiation readings could have been due to inaccurate VY detection equipment.

“What is serious is the possibility that VY radiation detection was off by a whopping factor of four and/or the probability that the contents of the package leaked and/or became more exposed as shielding shifted or settled,” Shadis said in an e-mail to the Vermont Guardian.

At 820 millirem per hour, a person exposed to the hottest part of the container could have, in one hour, received eight times the annual dose allowed by the NRC, or their annual allowable dose in less than eight minutes, Shadis noted.

Unlike the DOT, the NRC does not set a contact exposure ceiling, but the agency limits exposure for members of the public to 100 millirem annually.

“This is just a real sloppy performance,” Shadis continued. “Let's hope it is an exception and not the standard.”