Two separate investigations into how a contract employee snuck a small firearm past stringent security checkpoints at Browns Ferry Nuclear Plant are still ongoing, officials said Monday.

Jim Hopson, spokesman for Tennessee Valley Authority, said there were no new details to share about the March 2 incident. He explained the utility did implement “enhanced security measures” at Browns Ferry and its two other nuclear plants after the incident.

“We just wanted to be sure we don’t have some kind of systemic issue,” he said.

He said the outcome of the TVA’s investigation would determine what corrective actions should be taken to prevent another occurrence.

The U.S. Nuclear Regulatory Commission is conducting a separate investigation into the incident but provided no specific details.

“ … (The) inspection will look at how the event happened, whether there were violations of NRC requirements and what steps TVA has taken or is taking to minimize the likelihood of such an event happening again,” said a statement from the NRC.

The statement also said the commission would discuss its findings with TVA after the investigation is complete, but that those findings would not be made public.

About the incident

The contractor who brought the weapon into the plant was assisting in the scheduled refueling and maintenance outage on the plant’s Unit 2. After the weapon was discovered, he was escorted off site and his nuclear clearance was revoked.

Hopson previously said there were no injuries or safety threats to employees or to the public, but the plant did declare an “Unusual Event” after the discovery.

Unusual Event declarations are the least severe of the four emergency classifications.