Salt rock debris was discovered last Tuesday by ground control crews during routine monitoring and inspections of the Panel 4 entrance within the Waste Isolation Pilot Plant (WIPP) underground.
Panel 4, one of the most southern portions of the WIPP, was closed in 2010 and consists of seven disposal rooms filled with transuranic (TRU) waste. No WIPP personnel were present at the time of the salt rock fall, as the area had already been under restricted access — requiring management approval to access — since March 2016.
Recently, access was more strictly prohibited — no personnel entry allowed — since Sept. 21, when geotechnical engineers discovered that a temporary closure bulkhead in Panel 4 was bulging from pressure exerted from natural movement of the salt.
Since Panel 4 access drifts were closed in 2010, in accordance with procedures approved by the New Mexico Environmental Department, an internal review post-rockfall indicated that no personnel have been in the entrance of the panel for over six months. The deformation of bulkheads, like the entrance to Panel 4, is due to natural “salt creep” — which is one of the reasons that salt is the chosen disposal medium for TRU waste. This salt rock fall occurred in the access drift near a filled and closed panel, well away from the area where waste emplacement operations will take place.
The Nuclear Waste Partnership (NWP) is working closely with the workforce and their geotechnical experts to identify any additional areas of the underground that may need to be closed because of ground control concerns. The WIPP’s ground control team is responsible for monitoring the movement of the salt in open areas of the mine. Ground control is one of the highest priority operations to ensure the safety of the WIPP workforce. The area where the rock fall occurred had already been restricted to worker access due to previous findings.
Certain underground areas at the south end of the mined areas have been restricted, and only geotechnical experts performing ground control inspections can enter with authorization from NWP senior management. This event occurred far from currently planned waste emplacement operations and is not expected to affect the resumption of waste emplacement activities.
Contractor Operational Readiness Review Begins
Oct. 3 marked the beginning of the Contractor Operational Readiness Review (CORR). Having successfully started up the new Interim Ventilation System and closed out all of the pre-start findings from the Management Self-Assessment (MSA) and the CORR Plan of Action prerequisites, the NWP held its kickoff meeting Monday.
Last week, the NWP completed the remaining pre-start activities, including a successful demonstration of waste emplacement in the underground using full personal protective equipment. The NWP is utilizing a team of independent subject matter experts to conduct the CORR, which focuses on the following:
• Implementation of all corrective actions associated with the Accident Investigation Board;
• Implementation of the Safety Management Program corrective actions; and
• Ensuring the plant, people and processes are ready for safe and compliant resumption of waste emplacement activities.
“Think of it this way,” said Phil Breidenbach, NWP president and project manager. “The Management Self-Assessment was like a chapter test, the CORR is the midterm exam, and the Department of Energy Operational Readiness Review (DOE ORR) will be the final exam. I’m very proud of our workforce.”
