Environment & Science
6:52 pm
Tue May 7, 2013

Palisades leak angers Congressman Upton; new documents show alternative fix for leaky tank

A powerful voice in Washington is demanding a permanent fix to the leaky water tank at the Palisades Nuclear Plant.

Congressman Fred Upton says he’s “outraged” by the unplanned release of slightly radioactive water into Lake Michigan over the weekend. Regulators say there is no risk to public safety.

Upton chairs the House’s Energy and Commerce Committee, which has jurisdiction over domestic nuclear regulatory activities.

The plant is in Congressman Upton’s district. Entergy, the company that owns the plant, was one of the top contributors to his election campaign last year.

Upton is demanding accountability and a permanent fix to the tank, which has leaked on and off for at least two years.

In a written statement, Upton says he plans to personally visit the site with a Nuclear Regulatory Commissioner.

“It is my understanding that the water tank will be emptied by the end of the week with the hope that the cause of the leak can be identified shortly thereafter.  Every option must be on the table – including a full replacement of the tank – to ensure that the continuing leak will not occur again,” Upton said.

Requests for an interview were not immediately returned.

New documents show Entergy had asked regulators for an alternative fix for the leaky tank on April 25th. Those documents assumed the leaks had stabilized.

“The current leak rate is stable without an increasing trend which suggests that the current through wall flaws have self-relieved the initiating stresses, are not growing, and remain well below the calculated allowable flaw length.”

The Nuclear Regulatory Commission is investigating why the leak rate went from one gallon per day late last week to 90 gallons a day in one 24-hour period.

In the documents, Entergy requests an alternative fix for the tank “that would add a fiberglass-reinforced vinyl ester liner to the tank bottom and to a portion of the tank wall in lieu of identifying the location of the thru-wallleak(s) and performing code compliant repairs.”

The liner would cover the bottom of the tank and two feet up the interior walls. The company says it plans to install the liner in the fall during a scheduled refueling outage. The plant says a similar liner was installed at a plant in Florida.

“(The liner) will eliminate tank bottom leakage by forming a leak tight membrane on the tank bottom, isolating leak pathways. It will provide the required containment of the tank contents in lieu of relying on the existing aluminum tank bottom for this function. Further degradation of the welds in the current aluminum boundary is not expected based on ENO's understanding of the cause of the leakage and the repairs that have been performed. If any further weld degradation were to occur, the degradation will not affect the lining since the lining will be a distinct and independent material. While bonded to the surface of the existing tank, the physical properties of the liner will prevent potential future weld degradation, if it were to occur, from propagating into and through the liner.”