Contaminated water issues dominated TEPCO’s work and reporting out of the plant.
The ALPS system intended to remove some of the radioactive isotopes the other filtration systems can not began testing in September 2013. There are now three trains of the system but all are still in testing operation trying to work out issues in the system. TEPCO originally planned to start full scale operation in September.
In April of 2013 the silt fence for the port failed allowing highly radioactive fish to escape into the environment. Some of these fish had 6 digit cesium levels and unknown levels of other contaminants.
TEPCO installed a number of in ground ponds with covers to store water they planned to have run through the ALPS system. When ALPS began to fall behind schedule they began just dumping excess radioactive water into the ponds. It was found that TEPCO cut corners on the pond design. Instead of being built to standards to hold radioactive water, they were built similar to dry landfill standards. The ponds leaked contaminated water into the soil. TEPCO continues to use these ponds to hold contaminated rainwater.
TEPCO prepared a set of groundwater bypass wells on the hill above the reactor buildings These wells are downstream of the contaminated groundwater flow and have been documented to have cesium and tritium in them. IRID instructed TEPCO to begin building a different type of bypass system that would be larger and reside upstream from the plant grounds. TEPCO is currently trying yet again to sell the public on using the old contaminated set of bypass wells.
There has been a push for the installation of underground walls to stop leaks at the plant from reaching the sea TEPCO has been reluctant to begin either project citing concerns they may not work. Price has also played a role.
Further testing of ALPS showed that it does not remove certain isotopes including cobalt 60 and iodine 129. Iodine 129 has a half life of 15.7 million years. TEPCO found damage and leaks in the holding tanks of ALPS in July. The corrosion appeared at the worst on welds for the tanks. These appear to possibly be due to poor welding. TEPCO later found corrosion elsewhere in the system.
By May 2013, the Japanese government had ordered TEPCO to install the frozen underground wall system to try to block contaminated water from leaking into and out of the reactor buildings.
TEPCO was reprimanded for improper testing procedures to determine radioactive contamination levels at the plant. This has become an ongoing problem with later admissions of incorrect strontium 90 readings and that TEPCO was hiding data from the public for months. In June they admitted considerable amounts of strontium 90 were involved in the leaking water at the plant.
By July NRA also confirmed that the plant was indeed still leaking considerable amounts of contaminated water to the sea. Something researchers had been saying for almost a year. As the leaks became confirmed the Japanese government said they would become more involved in efforts to stop the leaks, including funding some of the work. At the same time the NRA criticized TEPCO for sloppy inspections and insufficient record keeping of the contaminated water and leaks at the plant.
Tanks containing highly radioactive sludge from the reverse osmosis system were found to be leaking. Some of that contamination made it to the sea via the drainage system at the plant. This brought up the realization that the drainage system at the plant was still being allowed to flow freely to the sea from the plant. Nobody had thought to do anything to regulate, monitor or block it. Concrete slabs placed as foundation and containment for these bolt together tanks were found to have subsided and gapped. TEPCO also discovered how the bolt together tanks were leaking, gaskets were damaged during installation and eroded from the toxic soup being stored in the tanks.
The tanks leaks have been quite serious with one hitting 1.8 sieverts/hour. As typhoons began to hit the plant in September rainwater caused the weirs around the tanks to overflow. This allowed potentially contaminated water to again flow out to sea.
Around the same time TEPCO admitted they knew about the groundwater leaks to the sea by May of 2011 but opted to not make this public or take any action. They feared their stock price would drop if they spent the 1 billion USD needed to install an underground wall. The Japanese government also knew and cooperated with TEPCO in hiding this from the public.
ALPS continued to have problems. After trying another test run it had to be abruptly shut off. Workers left a rubber mat inside one of the tanks. By January 2014 ALPS was still not in operation with a start date still unknown.
Another set of storage tanks were found to be leaking. This set was due to the soil under the concrete slab sinking causing the tank to sit at an angle and leak from the top. As tanks continue to leak, IRID decided to do a test run of the underground zeolite technology we proposed. A test site near the H4 tank farm was selected and is being installed. The hope is that it can prevent some of the migration of underground contaminated water.
As yet another typhoon began to hit the plant, TEPCO released rainwater that had collected around the tanks. This typhoon caused an increase in contamination being found in the drainage ditches that lead to the sea. The constant ongoing leaks caused IRID to direct TEPCO to take new measures to prevent contamination from washing out of the plant.
Deep underground monitoring found contaminated water underneath unit 4. This indicated that contamination has reached the deeper groundwater and could find routes out to sea that could be difficult to block. Strontium 90 began to show up in these deep wells, raising concerns about more complex contamination going on.
At the end of the year ALPS hit another big snag. Part of the process was found to be more inefficient than was estimated. They can operate this part of the filtration system but it is creating a huge volume of highly radioactive waste material that will have to be stored.
Research began research to come up with a way to plug the reactor downcomer pipes. This could potentially give them a way to block water from leaking out of the reactor containment. By January 2014 the first test location for the frozen wall had begun with good results. It is still not clear if this technology will be able to block all of the leaking water.
Leaks and failures caused by human error continue to plague the plant. A cooling water leak was found to have been caused by over tightening and bending of a flange. TEPCO opts to blame the on the ground workers but the media has shown how the contractor system and poor oversight has created the environment where mistakes happen.
TEPCO also admitted withholding strontium 90 readings for months. This avoided the bad news coming out as the bid for the olympics was being decided. The readings released later were also found to drastically underestimate the actual levels of strontium 90 being found. Soon after, record high strontium 90 readings were admitted near the sea front along with some of the highest cesium readings found to date. In February another tank farm was found to be leaking, this one leaked 23 Tbq in just one incident. Today the plant continues to leak contaminated water to the Pacific.
This article would not be possible without the extensive efforts of the SimplyInfo research team
Join the conversation at chat.simplyinfo.org
© 2011-2023 SimplyInfo.org, Fukuleaks.org All Rights Reserved Content cited, quoted etc. from other sources is under the respective rights of that content owner. If you are viewing this page on any website other than http://www.simplyinfo.org (or http://www.fukuleaks.org) it may be plagiarized, please let us know. If you wish to reproduce any of our content in full or in more than a phrase or quote, please contact us first to obtain permission.