“BUCHANAN – The likeliest source of the radiation leak at Indian Point is a
huge holding tank filled with water that cools and shields used plutonium
fuel rods hot enough to catch fire if the pool were drained – and dangerous
enough to kill anyone who comes in contact with them.
“If you were exposed in close proximity, unshielded, it would be fatal,”
Neil Sheehan, the spokesman for the Nuclear Regulatory Commission, said of
the processed uranium pellets used to help generate thousands of megawatts
of electricity at Indian Point. “We’re talking here about high-level,
radioactive waste.”
Concerns about the leak have grown, especially since strontium 90, a
byproduct of uranium and plutonium, was found in monitoring wells near the
Hudson River. At elevated levels in drinking water, the isotope increases
the risk of cancer.
NRC officials say it is the only case of strontium 90 leaking at any of the
nation’s 103 working nuclear plants, but that it has not reached drinking
water sources near Indian Point.
Tritium and nickel 63 also have been detected, but not at levels that alarm
regulators.
Nuke pool
To keep workers and the public safe, Indian Point maintains three spent fuel
pools, using 90-degree water as both a shield and a cooling mechanism for
its nuclear fuel rods.
The 30-foot-by-30-foot pool that company officials are looking at sits next
to Indian Point 2, a reactor that powered up about the time President Nixon
resigned, and a few months before Indian Point 1 shut down in October 1974.
Despite sitting in a half-inch- thick stainless-steel liner surrounded by
concrete up to 6 feet thick, water from the 400,000-gallon pool began
seeping through a hairline crack at the base of the structure in August. The
breach has led to a special inspection by the commission, the drilling of 23
new testing wells, and public concerns about safety.
“You don’t want to lose any water in the pool,” said Jim Steets, the
spokesman for Entergy Nuclear Northeast, the company that owns the two
working nuclear reactors at Indian Point. “But a lot of the things we deal
with every day are dangerous. What’s important is knowing how to deal with
them.”
NRC scientists have said repeatedly that the leak does not constitute a
threat to public health. Still, the perception of a radioactive leak of any
kind has some residents of the Lower Hudson Valley concerned.
“There’s got to be a defect in the steel wall of some kind,” said Buchanan
resident Jim Siermarco, who worked with radioactive isotopes early in his
career at IBM and monitors Indian Point as a volunteer for the
village.”There’s a pinhole or a crack somewhere. If it’s down where the fuel
rods are, it’s going to take time to fix it.”
Entergy officials say that’s a strategy they’re pursuing, after having
little success inspecting the two-thirds of the 40-foot-deep pool accessible
to divers.
The remaining portion will require special underwater cameras and robotics
to go where the fuel assemblies sit in racks in bundles of about 200 fuel
rods, each about 12 feet high.
Company officials say they believe they have found a vendor qualified to
inspect that area and apply special epoxy to any flaws that turn up. Entergy
has encapsulated the cracks on the exterior walls, and now says that leakage
has stopped.
But with strontium 90, tritium and nickel 63 showing up in numbers not seen
on the site before, experts say they believe there is still radiated water
leaking from somewhere.
Other leaks?
One possibility is that the stainless-steel liner is intact, but that the
water from an earlier leak in the liner – since patched – has finally found
its way through the more porous concrete. The escaped water could date back
to when Consolidated Edison ran the plant in the 1990s.
So far, tests to determine whether the leak started more than a decade ago
have been inconclusive, but are continuing.
The water has traveled to a monitoring well within 50 yards of the Hudson
River, bringing the isotopes with it. The water is still contained on the
site, and has not reached drinking water sources, the NRC said.
One longtime industry watchdog said Entergy’s efforts to find the source of
the leak and determine the extent of contamination show that Indian Point
officials see the economic advantage of running a safe plant.
“The company could have tried to explain away a lot of what they’ve found
with some hand-waving,” said David Lochbaum, a nuclear safety engineer with
the Union of Concerned Scientists, an independent nonprofit alliance of
citizens and scientists. “They seem to be going after a comprehensive set of
answers.”
Though there has been a lot of data and scientific analysis of the leak
since September, federal and company officials agree that the list of
questions continues to grow, and will require methodical research to finish.
“There are several remediation strategies that we can follow,” said Steets,
Entergy’s spokesman. “We haven’t reached the point where we know what is
best to do. If this thing were on the edge of a public safety issue, we
would be taking mitigation measures sooner. Some of this just takes time. We
don’t want to make too quick a decision out of reaction to the public
interest in this.”
Steets said the company also is looking closely at the fuel pool of the
defunct Indian Point 1.
That pool leaks 25 gallons of radiated water a day into a specially built
set of curtain drains. The drains capture water and allow it to be measured
for radioactivity before it is released in accordance with the plant’s
permits.
During heavy rainstorms, however, the capacity of that system and its drains
and holding tank are pushed to their limits, Steets said.
Safe storage
The future appears to be dry cask storage. Entergy officials are creating a
site for storing its nuclear waste in containers that seal the expended fuel
pellets and cool them with helium or inert gases instead of water.
Eventually, the hope is to move them to a safe, national storage site.
The fuel pools would still be necessary to allow for a long-term cool-down
period – probably five years – but wouldn’t be the only storage method on
site.
“Most plants are running into a space crunch,” said the NRC’s Sheehan. “At
some point you have to look at alternatives to store the waste.””
