45-year-old construction error revealed in leaking tank at Entergy's Palisades atomic reactor

Entergy and NRC have just discovered that, at Palisades, plant diagrams are not accurate depictions of "as-built" realityAs reported by Andrew Lersten at the St. Joe Herald-Palladium, a 45-year-old construction error has been discovered at Entergy Nuclear's problem-plagued Palisades atomic reactor on the Lake Michigan shoreline in southwest MI. While repairing a 300,000 gallon tank of water that has been leaking for over two years -- including into the safety-critical control room, as well as directly into Lake Michigan -- workers found that a grout ring and sand bed region called for in the blueprints had never been installed back in 1968. Entergy and NRC now admit that phantom structures assumed to have been there all along may go a long way to explaining why the floor of the tank has suffered repeated leaks, despite multiple attempted repairs.

As recently as April 25, 2013, in a submission to NRC, Entergy gave engineering credit to structures which, in reality, didn't even exist: "Pressure stress loads are carried by the sand base, concrete grout ring, and concrete foundation beneath the tank bottom."

The discrepancy between Palisades' blueprints (see image, left), and the actual "as-built" reality, raises serious safety significant questions about the entire atomic reactor.

The Herald-Palladium, for whom Palisades unquestionably could do no wrong for decades on end, published a blistering editorial on May 23rd. The editorial board concluded:

"...as events in Japan proved in 2011, there is really no second chance when it comes to a catastrophic nuclear event.

We know that Entergy officials will say emphatically that they understand the stakes and are doing everything possible to maintain safety. But talk is cheap, and past problems at the plant don’t inspire confidence. What is really needed are better results.

Should Palisades continue to stumble along in the next months and years, then we hope the NRC takes a much harder look at Palisades’ license. Energy production and commerce are important, but not nearly as important as the safety and well-being of an entire region."

NRC rubber-stamped Palisades' 20-year license extension in 2007, allowing it to operate till 2031.