Entergy has notified local and federal officials of a release of radioactive tritium into a storm drain.
The amount of tritium found by Entergy in a routine sample taken from a storm drain on Dec. 23 is very small, the company told the Nuclear Regulatory Commission in a public filing made on Monday afternoon.
It is less than 1/30th of the amount needed to trigger automatic notification of local, state and federal officials. Entergy said in the filing that because the tritium was found in a storm drain, the company decided it was prudent to notify officials anyway.
Workers found tritium on Nov. 3 in a sump connected to the storm drain, but not in the storm drain itself or in ground water monitoring wells. At the time, the company ordered increased monitoring of the sump. Now, the sump will be tested daily and the storm drain will be tested weekly.
Tritium is an isotope of hydrogen. For a radioactive element, it has a relatively short half-life, a little more than 12 years. Tritium is used in the nuclear power process, but it can also be found as the glowing elements in many wrist watches.
Tritium can cause burns to skin and can be dangerous if it is inhaled or swallowed but the radiation it gives off is said to be too weak to penetrate the skin. It decays in about two weeks inside the body.
It is produced in very small amounts in nuclear energy production. The government estimated in 1996 that only about 500 pounds of tritium has been created since 1955, and because it decays so quickly, only a little more than 150 pounds was in the government’s stockpile at that time.