San Onofre Hydrogen Gas Leak Exposes Danger of Restart

By Becca Connors, Friends of the Earth

24 October 12

The hydrogen gas leak at the San Onofre nuclear plant appears to have been repaired. Edison has submitted a report to the Nuclear Regulatory Commission. It is not certain when or if the nuclear plant will be restarted.

reactor at the crippled San Onofre nuclear power plant is leaking hydrogen gas into the environment, according to the U.S. Nuclear Regulatory Commission. Although it  is not yet known if the leaking gas is radioactive, Friends of Earth said the latest trouble at San Onofre is strong evidence that the plant is not safe to restart.

According to a NRC bulletin issued Sunday, an unknown quantity of hydrogen gas was leaking from Reactor 2, which like Reactor 3 has been closed since a leak of radioactive steam in January and the discovery of severely damaged steam generators. The NRC did not say what caused the leak.

"There are critical questions that Edison must answer immediately," said Damon Moglen, energy and climate director at Friends of the Earth. "Is the leaking hydrogen radioactive? And was the leak caused by heating up the plant's steam generators in advance preparation for restart? Edison keeps saying safety is its priority, but it's clear that the San Onofre reactors are not safe to operate."

Both the California Emergency Management Agency and San Diego Department of Environmental Health were notified of the leak Sunday morning.

Earlier this month, Edison filed a plan to restart Reactor 2 at 70 percent power and run it for five months to see whether it is safe to restart permanently. The NRC says it will take months to decide whether to allow restart.

This past weekend, Edison was conducting tests that include bringing the reactor to normal operating pressure and temperature, using offsite electrical power. The steam generators will be hot and pressurized. The leak is likely to persist for some days, as the only way to stop such a leak is to depressurize and lower the temperature of the reactor and its coolant system. This is a delicate operation that must follow rigid safety rules to avoid further damage to the reactors.

"This has all the signs of a bungled and hurried preparation to bring San Onofre Unit 2 back to power," said John Large, a London-based nuclear consultant. "Depending on the extent of damage to the reactor this could be a further setback to Edison's plans for an early restart."