Fort Calhoun Nuclear Plant: Flood Seeps Into Turbine Building

OMAHA — Missouri River floodwater seeped into the turbine building at a nuclear power plant near Omaha on Monday, but plant officials said the seepage was expected and posed no safety risk because the building contains no nuclear material.

An 8-foot-tall, water-filled temporary berm protecting the plant collapsed early Sunday. Vendor workers were at the plant Monday to determine whether the 2,000 foot berm can be repaired.

Omaha Public Power District spokesman Jeff Hanson said pumps were handling the problem at the Fort Calhoun Nuclear Station and that “everything is secure and safe.” The plant, about 20 miles north of Omaha, has been closed for refueling since April. Hanson said the berm’s collapse didn’t affect the shutdown or the spent fuel pool cooling.

Floodwater in nuke plant

Nuclear Regulatory Commission spokesman Victor Dricks described the situation as stable. NRC Chairman Gregory Jaczko plans to inspect the Fort Calhoun plant on Monday as part of a pre-arranged visit to Nebraska.
Hanson said OPPD fired up generators and cut the power supply after water surrounded the main electrical transformers on Sunday. The generators powered the plant until an off-site power supply was connected later in the day.
Officials said the berm wasn’t critical to protecting the plant, which sits across the river from Iowa. “There are other structures and systems in place that can ensure they will continue operating safely,” Jaczko said Sunday.

The river was not expected to rise higher than the level the plant is designed to handle. Jackzo inspected the Cooper Nuclear Station, which sits on the Missouri River about 75 miles south of Omaha, on Sunday. He asked plant officials and the NRC’s local inspectors questions about the plant and this year’s flooding.

source: http://www.huffingtonpost.com/2011/06/27/fort-calhoun-nuclear-flood-nebraska-plant_n_885067.html

Flood wall fails at US nuke plant Fort Calhoun

Water surrounded several buildings at the Fort Calhoun Nuclear Station on Sunday after a water-filled floodwall collapsed.
The plant, about 19 miles north of Omaha, remains safe, Omaha Public Power District officials said Sunday afternoon.
Sunday’s event offers even more evidence that the relentlessly rising Missouri River is testing the flood worthiness of an American nuclear power plant like never before. The now-idle plant has become an island. And unlike other plants in the past, Fort Calhoun faces months of flooding.
Flood walls collapsed

Floodwater surrounded the nuclear plant’s main electrical transformers Sunday after the Aqua Dam, a water-filled tubular levee, collapsed, and power was transferred to emergency diesel generators.
OPPD officials said the transfer was precautionary because of water leaking around the concrete berm surrounding the main transformers.
Efforts were underway to reconnect to offsite power once all safety checks have been completed.
Water now surrounds the auxiliary and containment buildings, which are designed to handle flooding up to 1014 feet above sea level.
The river is at 1006.3 feet and isn’t forecast to exceed 1008 feet. The U.S. Nuclear Regulatory Commission is monitoring the Missouri River at the plant, which has been shut down since early April for refueling.
The Fort Calhoun plant will remain surrounded at least through August as the U.S. Army Corps of Engineers continues dumping unprecedented amounts of water from upstream dams.
The 2,000-foot berm collapsed about 1:25 a.m. Sunday due to “onsite activities,” OPPD officials said. The Aqua Dam provided supplemental flood protection and was not required under NRC regulations.
“We put up the aqua-berm as additional protection,” said OPPD spokesman Mike Jones. “(The plant) is in the same situation it would have been in if the berm had not been added. We’re still within NRC regulations.”
The NRC says its inspectors were at the plant when the berm failed and have confirmed that the flooding has had no impact on the reactor shutdown cooling or the spent fuel pool cooling.
The NRC said there is a separate, earthen berm to protect the electrical switchyard and a concrete barrier surrounding electrical transformers.

Last week, the NRC augmented its inspection staff at Fort Calhoun. In addition to the two resident inspectors, three more inspectors and a branch chief were added to provide around the clock coverage of plant activities.
Both the plant’s operator, the Omaha Public Power District, and federal regulators say the plant remains safe.
source: http://www.omaha.com/article/20110626/NEWS01/110629782/1014