A change in Department of Energy’s standards, damage to a key piece of equipment and review of recommendations by the Accident Investigation Board for implementation all played a key role in the decision, which was announced on Friday.

The plant had been closed since a radiation leak was detected in February 2014, and a new opening date is being evaluated based on those challenges.

“We are disappointed that we will not meet the original target date for beginning waste emplacement, but (we) do not want to lose sight of the substantial progress that has been made in the recovery of the WIPP site, including great strides in mine stabilization, radiological risk mitigation and the closure of Panel 6 and Panel 7 Room 7, all of which have significantly increased safety in the underground,” said acting Carlsbad Field Office Manager Dana Bryson in the release.