CNO Summit Diary: Why FLEX Is The Right Response to Fukushima

Maria Korsnick

Constellation Energy Chief Nuclear Officer Maria Korsnick was in Japan last week touring the country’s nuclear facilities with a prominent group of U.S. chief nuclear officers. 

This is the second in a series of travel logs that Maria recorded. You can read an earlier diary entry from Maria, here. Additional coverage of the CNO Summit is on Twitter at #CNOSummit.

Earlier this week I toured Fukushima Daiichi and Fukushima Daini. The stations are only 7.5 miles apart but the contrast is remarkable. When approaching Daiichi, we were stopped at a village 12 miles from the station. The area was previously used as a training facility for Japan's soccer team, but today it serves as temporary housing for site workers and a plant access checkpoint. Each of us received a whole body count before boarding a bus to Daiichi.

The view from the bus window will stay with me forever. It looked like a war zone. The earthquake and the force of the tsunami were evident everywhere. The town was empty, the houses are decaying and the storefronts are damaged. You are surrounded by broken glass, twisted metal and overturned vehicles. Large storage tanks have been torn from their mounting plates and pushed aside. Pieces of the reactor building serve as constant reminders of the hydrogen explosion.

When we arrived at the site we were issued paper face masks, anti-contamination clothing and shoe covers. We dressed out and boarded another bus to tour the station grounds. The seats are covered in pink plastic herculite sheets to further protect us from contamination. As we drove the site, I could see that many buildings were still uninhabitable. Others had been converted to shift worker resting areas or additional checkpoints.

There are six reactors on this site. Units 1, 2 and 3 have damaged cores. Units 4, 5 and 6 do not, but they will never operate again. Decommissioning the entire site will take 30+ years. The biggest challenge right now is water: too much of it in the wrong place to be exact. Rows and rows of large tanks, similar to our condensate storage tanks, are being used to hold contaminated groundwater. The earthquake collapsed the underground drainage system, so the groundwater is collecting around the buildings and leaking in. The reactor building is contaminated from the accident, so the water becomes contaminated, too. They pump the water into the tanks to clean it, but keeping up with the volume of water is very challenging and they can't discharge anything. Even water clean enough to meet U.S. EPA standards cannot be discharged.

Currently they are clearing more land and installing more tanks, but a better solution is needed. Making matters worse, many of the original tanks were bolted together, not welded, and prone to leakage. Cleaning up water and fixing leaks continues 24/7 while they seek a viable long-term solution. It's a massive challenge but it’s evident that they are working very hard to get their arms around it.

The following day we toured Fukushima Daini and its four reactors. The station is only 7.5 miles from Daiichi, so it experienced the same earthquake and tsunami. They also lost power and their emergency diesels and electrical cabinets were affected by flooding. Damage is evident in a few places but, for the most part, the station has been cleaned up and repaired. They fought the same storm, but with the benefit of a few design and response differences, they won.

Unlike Daiichi, Daini retained power to some of the instrumentation in the control room, so they could assess the status of key systems. They were able to rally their site team and find creative solutions. They ran over six miles of heavy electrical cable, in about a day, to bring in offsite power to support their safety systems. Over 500 employees stayed for weeks to support the site. It's an amazing story of an engaged team, under extreme stress, with strong leadership that brought amazing results.

It's clear that the negative outcome of Daiichi overshadowed Daini's remarkable performance. As nuclear professionals, we can learn as much from what went right as we can from what didn't. They proved that our portable, diverse equipment strategy know as FLEX can be successful in protecting their plant and their people. Back home, we need to continue to prepare for and defend against beyond design events. With pre-staged, portable equipment, we can give our team options. The equipment is in place now, but additional training and procedural guidance over the next several months will make us even better prepared for the unimaginable.

Standing here at Fukushima Daini, I'm confident that our FLEX strategy is the right approach for our stations and the industry as a whole. I'm comforted to know that it worked here, and very thankful to our Japanese colleagues for their dedication, hard work and many successes.