Pipe Leaking Radioactive Water

Greg Clary, The Journal News
BUCHANAN - Indian Point 2 has sprung a new leak of radioactive water that may force company officials to shut down the nuclear reactor to repair a cracked pipe about 8 feet below ground.The 8-inch pipe is leaking about 18 gallons of tritium and water a minute, and workers at the plant have been digging since early Monday morning, when water showed up near a manhole cover, regulators and plant officials confirmed to The Journal News.
The leaking pipe connects to a tank that stores condensation from steam generators used to turn turbines that produce electricity.
The pipe is not on the nuclear reactor side of the operation, so concentrations of radioactive tritium are about 2,000 picocuries per liter, a tenth of federally allowable maximum levels for safe drinking water.
Tritium is a radioactive isotope of hydrogen that is produced naturally in the upper atmosphere and can be found as a gas, but most commonly occurs in water, which is formed when tritium is exposed to oxygen.
It also is produced during nuclear weapons' explosions and in reactors. Nuclear regulators say a person would "have to consume a lot for a long time in order to see significant health effects."
The tritiated water is going into the Indian Point's discharge canal, which drains into the Hudson River under federal permit. Nuclear Regulatory Commission officials said there is no risk to local drinking water sources.
The repairs have to be made within seven days of the discovery of the leak, according to NRC regulations, or the reactor must be taken offline.
"The condensate storage tank plays a very important role in terms of safety," NRC spokesman Neil Sheehan said. "If you have an accident involving the reactor such as a pipe rupture, you would take water off the tank to keep the fuel covered and cool until you could switch over to the sump at the bottom of the building."
Officials for Entergy Nuclear, the plant owner and operator, said they were able to find the leak by 5 p.m. Wednesday after digging through the floor of the auxiliary feedwater pump building.
Entergy spokesman Jim Steets said workers would likely have to shut off valves to the pipe to make the repairs, much as would be done in the event of a water-main break under a typical street.
"In a situation like this, you have to assume the worst and prepare for it," Steets said. "But that water is run through our cleaning system to take out as many minerals as possible because over time they corrode the tubes. It's the cleanest water possible."
Indian Point has had trouble with tritium and other leaks, including the more dangerous strontium 90, since August 2005, when excavation work on a new crane site turned up a crack in the spent-fuel storage pool at Indian Point 2.
Those tritium concentrations at their worst topped 500,000 picocuries per liter and helped prompt the NRC to create a tritium task force because of a growing concern about such leaks nationwide.
The company will now have to examine other on-site piping that is similar to the broken line to ensure that the problem isn't more widespread at the plant than it appears now.
NRC officials said an initial examination determined that a portion of the pipe's external coating, which is intended to inhibit corrosion, was missing at the location of the leak.
The issue of aging infrastructure under the ground at the Buchanan plant is one key concern state officials and others have raised during the relicensing.
State Attorney General Andrew Cuomo, the state Department of Environmental Conservation and the environmental group Riverkeeper are among those who are fighting against granting Indian Point a 20-year extension of its license.
One of their arguments is that Entergy can't properly evaluate the conditions of its underground pipes to determine how the infrastructure will hold up through 2035.
Attempts to reach those participants in the relicensing process yesterday were unsuccessful.
Steets said the plant has a continuing maintenance and inspection program that keeps such ruptures to a minimum.
"You don't expect the pipes to be weak, but it happens," Steets said. "There are up to 100,000 gallons of water continually passing through these pipes. There is no way to prevent everything. You just have to be prepared to make repairs."
NRC staff members have said aging infrastructure management is an everyday operational concern, not an argument that belongs in the relicensing debate, but that argument was turned down by the reviewing board.
Additional Facts
About tritium
- Tritium is a radioactive isotope of the element hydrogen. It is naturally produced in the upper atmosphere when cosmic rays strike air molecules and as a byproduct in nuclear reactors that produce electricity.
- It readily forms water when exposed to oxygen and almost always is found as tritiated water. It primarily enters the body when people swallow tritiated water. People also may inhale tritium as a gas in the air or absorb it through their skin.
- Once tritium enters the body, it quickly disperses and is uniformly distributed.
- As with all ionizing radiation, exposure to tritium increases the risk of developing cancer. However, tritium is one of the least dangerous radionuclides because it emits very weak radiation and leaves the body relatively quickly. Since tritium almost always is found as water, it goes directly into soft tissues and organs. The associated dose to these tissues generally is uniform and dependent on the tissues' water content.
- People are exposed to small amounts of tritium every day. It is widely dispersed in the environment and in the food chain.

Source: Environmental Protection Agency