Blog
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Geiger Readings for Sep 02, 2017
Ambient office = 99 nanosieverts per hourAmbient outside = 107 nanosieverts per hourSoil exposed to rain water = 108 nanosieverts per hourOrange bell pepper from Central Market = 121 nanosieverts per hourTap water = 70 nanosieverts per hourFilter water = 60 nanosieverts per hourDover sole – Caught in USA = 100 nanosieverts per hour -
Radioactive Waste 296 – New Study Finds No Danger From Fukushima Cesium Isotopes From Consumption of northern Pacific Fish
The Fukushima disaster in Japan in 2011 raised fears that the release of contaminated ground water and cooling water into the Pacific Ocean could contaminate fish that are caught for human consumption. TEPCO’s plan to release almost eight hundred thousand tons of tritium contaminated water into the Pacific Ocean is awaiting government approval. This has reignited the debate over the dangers posed by such releases.
Shortly after the Fukushima disaster, raised levels of radioactive cesium were found in bluefin and albacore tuna caught off the coast of California. Since ocean currents would take up to two years to move water from Japan to California, the presence of the cesium in the tuna indicated that those fish had swum six thousand miles in about two months to get to California from Japan.
These studies were undertaken to help understand the migratory patterns of the tuna but the presence of cesium from the Fukushima disaster did raise concerns about public health. Although the amount of cesium in the tuna was too low to be make the tuna dangerous for people to consume, public concern spread to other types of fish, sharks, and marine mammals as well as other areas of the U.S. and Canadian Pacific Coast.
A new study has just been released that finds the dangers of consuming meat from predatory Pacific fish such as tuna, swordfish and sharks is minimal. The study focused on cesium. Two radioactive isotopes of cesium, Cs-134 and Cs-137, are created when uranium decays in a nuclear reactor. A great amount of both of these cesium isotopes was released into the Pacific Ocean during the Fukushima disaster. They are especially dangerous because they have half lives of two years and thirty one years, respectively. They tend to accumulate in the muscle tissue of fish which are eaten by humans. Although they are washed out of human tissue within one hundred and fifty days, in large doses, they can be lethal.
Samples were taken from the tissues of predatory fish from across the northern Pacific between 2012 and 2015. These samples were from around Japan, Hawaii and California. The samples showed no detectable levels of Cs-134. Levels of Cs-137 were the same as the background levels set by nuclear testing in the Pacific in the 1940 and 1950s.
The lead author of the study said, “Our measurements and associated calculations of how much radioactive cesium a person would ingest by eating this seafood shows that impacts to human health are likely to be negligible. For marketed fish to be restricted from trade, the cesium levels would have to be more than 1,600 times higher than in any samples we measured.”
A co-author of the study said, “One goal of our study was to put these perceived risks in context by surveying a broad range of vertebrate species across the entire North Pacific for the presence or absence of Fukushima-derived radioactive cesium. Our results, which show very low or undetectable levels in these animals, are important both for public perception of seafood safety and for scientific understanding of radionuclide transfer. Go ahead and eat some sushi! Our work shows that radioactivity from the Fukushima disaster is very low in open-ocean vertebrates.”
Bluefin tuna:
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Geiger Readings for Sep 01, 2017
Ambient office = 119 nanosieverts per hourAmbient outside = 121 nanosieverts per hourSoil exposed to rain water = 116 nanosieverts per hourBeefsteak tomato from Central Market = 123 nanosieverts per hourTap water = 87 nanosieverts per hourFilter water = 80 nanosieverts per hour -
Radioactive Waste 295 – Disposition Of Spent Nuclear Fuel From Closed San Onofre Reactors Is Still Uncertain – Part 2 of 2 parts
Part 2 of 2 (Please read Part 1 first)
There are also discussions within the Trump administration about moving the spent fuel to the proposed nuclear storage facility at Yucca Mountain, NV. if the project can be revived and completed. Other facilities in other states have also been suggested.
SCE is committed to putting together a team of experts to come up with a plan for the relocation of the spent fuel. Experts in engineering, radiation detection and nuclear waste siting and transportation will be part of the team. SCE promised to develop a more efficient and timely program for inspecting the spent fuel currently stored in fifty dry casks behind a seawall at the SONGS site. They will also need to create a contingency plan for dealing with any problems that may be found with the existing storage canisters. SCE must spend up to four million dollars to carry out the terms of the settlement.
The president of SCE said, “SCE is proud to take a leadership role in what we expect will become an industry-wide effort over many years to work with the federal government and other key stakeholders to achieve off-site storage.” One of the plaintiffs suing the CCC is Citizens Oversight (CO) which is a San Diego-based watchdog group that has been opposed for years to the plan for onsite storage of spent fuel at SONGS. The national coordinator for CO said, “This [settlement] is about the best we can do, and I think it’s pretty good. It’s a prudent step in the right direction and a step [Edison] wouldn’t take at all if it weren’t for the lawsuit that we filed.”
The settlement sets up a timetable with a series of deadlines for finding a new location for the SONGS spent fuel and putting together the required team of experts. The search for qualified experts must begin within sixty days. The panel of experts has ninety days to hire qualified experts who apply.
The settlement plan still faces some significant problems. For one thing, even if SCE carries out all of its agreed upon actions and does identify a new location for the spent fuel and a plan for transfer, no transfer can take place unless approved by the Nuclear Regulatory Commission (NRC). While the waste is currently the responsibility of SCE, that responsibility will eventually have to handed over to the Department of Energy which will have to approve the handover. The Department of Transportation will have to approve any plan for transporting the spent fuel to a new location. All of the proceedings from these federal agencies will take time to carry out and new problems that may delay the plan may emerge from these proceedings.
One quote from the settlement stands out. SCE is committing to spending “commercially reasonable” funds to locate a new site for the spent fuel and develop a detailed plan for the transportation of the spent fuel to that site. A number of four million dollars is mentioned in connection with the settlement. It is not clear whether or not SCE is off the hook for moving the spent fuel if they spend four million dollars and still don’t have a site and/or a viable plan. Ultimately, the court did not say that they have to move the spent nuclear fuel. But, as the CO president said, this settlement is about the best they could hope for.
San Onofre Nuclear Generating Station:
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Geiger Readings for Aug 31, 2017
Ambient office = 98 nanosieverts per hourAmbient outside = 115 nanosieverts per hourSoil exposed to rain water = 129 nanosieverts per hourBrussel sprout from Central Market = 133 nanosieverts per hourTap water = 114 nanosieverts per hourFilter water = 100 nanosieverts per hour -
Radioactive Waste 294 – Disposition Of Spent Nuclear Fuel From Closed San Onofre Reactors Is Still Uncertain – Part 1 of 2 parts.
There are some ongoing disputes over nuclear issues that I return to from time to time for an update. The San Onofre Nuclear Generating Station (SONGS) near San Diego, CA. was shut down a few years ago over problems with the steam generator systems. Southern California Edison (SCE), the owners of the SONGS, contracted with Hitachi Heavy Industries for two new steam generators. In 2012, both of the SONGS reactors had to be shut down because of premature wear. Hitachi claims that they warned SCE that the design changes that had been made might cause problems with the new steam turbines and they did. SCE is suing Hitachi and Hitachi is suing the SCE.
SCE decided that to close the SONGS permanently in 2013 because of uncertainty of the cost and time involved in fixing the steam generators. The SONGS is being decommissioned and that means that something will have to be done with the spent nuclear fuel from the reactor cores and the cooling pool.
SCE proposed to store the nuclear waste in dry storage casks onsite at the SONGS. Seventy three thick vertical dry casks are being constructed onsite to receive the spent fuel currently in the cooling pool at the SONGS. Critics of the proposal point out that the site is right on the Pacific Coast of California with a heavily populated area and a busy freeway right on the other side of the site. California is a seismically active zone and there are fears that an earthquake off the coast could cause a tsunami that would flood the SONGS site.
Following the grant of a twenty year permit by the California Coastal Commission (CCC) in 2015 for the SONGS to store the spent fuel onsite, two plaintiffs from the San Diego area filed a law suit against the actions of the Commission. An out-of-court has just been reached between the plaintiffs and SCE. The settlement was approved by a Superior Court Judge. In the settlement, SCE has committed to making a “commercially reasonable” attempt to move the spent fuel from the SONGS to another facility.
The Palo Verde Nuclear Generating Station in Arizona has been suggested as a possible destination for the spent fuel from the SONGS. The Palo Verde site is a logical choice because that facility SCE is a part owner of Palo Verde which would reduce the complexity of the transfer.
Facilities in Texas and New Mexico are also being considered. They are “consolidated interim storage” facilities which receive spent fuel and other waste from multiple nuclear power plants if receipt is approved by local authorities.
Representative from the Eddy-Lea Energy Alliance which manages the nuclear waste facility in New Mexico came to San Diego to discuss their facility as a possible location for the SONGS spent fuel. They made the statement that, if the transfer was approved, they could get it done in five years. Given the long timelines and usual schedule delays in most nuclear projects, this would appear to be an over optimistic prediction.
The Texas site that has been suggested is managed by Waste Control Specialists. They want to expand their existing low-level waste facility but are having financial difficulties. These difficulties were exacerbated when the U.S. Justice department recently blocked a proposed merger.
Part 1 of 2 parts (Please read Part 2)
