Andrew Larkin: Future storms and aging reactors
This NOAA satellite image taken Tuesday, Oct. 30, 2012 at 1:45 a.m. EDT shows Sandy over much of the eastern United States extending from North Carolina to Illinois into the Northeast with areas of rain. Snow is seen over the Central Appalachians and back into Ohio and Michigan. (AP Photo/Weather Underground) Purchase photo reprints »
NORTHAMPTON — Recently superstorm Sandy struck the East Coast with devastating consequences, including major flooding and loss of electrical power. The Nuclear Regulatory Commission reported that the nuclear power plants withstood the stresses of the storm and are safe. However, a more careful analysis reveals the vulnerability of the plants.
There were 26 nuclear power plants in Sandy’s path. Some were of the same design as the GE Mark I boiling water reactors used in Fukushima; there are 23 of this model in the U.S., one of which is located at Vermont Yankee.
They were designed in the ’50s and built in the ’70s and many have passed their 40th year of operation, the limit for which they were built. Decades of radiation and high pressures — 75 atmospheres of pressure and temperatures of 285 degrees Celsius (550 degrees Fahrenheit) — plus the corrosive effects of water have caused damage to the materials. These plants must be constantly cooled. If they lose the ability to stay cool, they can cause destruction of the plant itself, as witnessed in Fukushima and Chernobyl.
At Fukushima the backup diesel generators failed because of flooding of the plant. Ed Lyman of the Union of Concerned Scientists reports that after Fukushima the NRC compiled a table of flood protection levels at all U.S. plants and found that many plants have little or no protection against maximum historical flooding levels. Researchers from Stanford University found that a 1938 hurricane produced a storm surge of 25 to 30 feet and that many of the plants are on average 20 feet above sea level and are vulnerable to historic high flooding.
With a loss of coolant there is a threat both to the core as well as the pools of spent fuel rods. If spent fuel rods are not cooled, the water evaporates in hours to a few days and exposes the spent fuel rods to oxygen; they burn and release massive radiation into the atmosphere. Many of these spent fuel pools hold five times as much fuel as they were designed for. The NRC does not require that spent fuel rod pools are connected to backup diesels used as cooling systems in the event of an emergency.
The steam release from these tanks can short out the electrical systems in the plant. The fuel in these tanks can be stored in dry casks, which are much safer, but the industry has not done this, presumably because of cost, according to Arnie Gundersen, chief engineer at Fairewinds Energy Education Corp., a nuclear energy advocacy group in Vermont.
Finally, the plants are vulnerable because of their connection to the grid. They are dependent on the grid both because their cooling systems run off the grid and because the plants stay cool by dissipating half of their energy onto the grid in the form of electricity.
At Indian Point, 25 miles north of New York City, Unit 3 was shut down because of disturbances of the electrical grid.
At Nine Mile Point near Syracuse, N.Y., Unit 1 shut down because it could not send power to the grid, and Unit 2 shut down because it could not receive power from the grid.
At Salem 1 in Hancocks Bridge, N.J., four out of six of recirculation pumps failed because the storm washed mud and grass into the pumps that were part of the cooling system.
The plant then released steam into the atmosphere. NRC spokesman Scott Burnell reported that only “very small amounts of tritium (radioactive water)” were released into the atmosphere.
At Oyster Creek in New Jersey there was “an unusual event” because rising tides, a full moon, wind and a storm surge threatened the plant’s water intake structure and a water pump. The storm also knocked out the emergency sirens, which were to warn the residents in the event of danger.
Locally, the plant at Vernon, Vt., reduced its output because of the loss of a transmission line in New Hampshire.
Nuclear power plants are complex structures, and a failure can have complex causes.
We were fortunate during the superstorm that none of the nuclear power plants lost their capacity to stay cool. If these diverse events had all occurred at a single plant, the consequences might have been devastating and unimaginable.
The liability of the nuclear industry is limited. Through the Price-Anderson Nuclear Industries Indemnity Act, U.S. nuclear facilities have paid $12 billion into a liability fund that would be used in case of a nuclear incident. Gundersen estimates the cost of cleanup at Fukushima to be about $500 billion. And our standard homeowner insurance policies exclude damage caused by nuclear accidents.
We are lucky that none of these sites have become household words such as Fukushima. The vulnerabilities have been exposed, the warnings are there. Must we wait for a complete meltdown before we stop risking our lives, our lands, our Earth itself on a dangerous source of energy?
Andrew Larkin is a retired physician living in Northampton.