On August 3, 2018, a 50-ton canister was being lowered into the underground vault when it came to rest on the edge of the guide ring, about 18 feet above the bottom of the vault. According to whistle-blower David Fritch, the canister was only held by a fraction of an inch while the crane system lowered and the support rigging became slack. The crane lowered all the way down and the workers were unawary of the danger for nearly an hour. They then noticed that it was not correctly loaded and raised the crane system to regain control, and then lowered it into the vault.
At the August 9 CEP meeting, SCE did not report on the incident until David Fritch reported it in the public comment period.