Mining of new waste disposal panel begins at WIPP

According to the DOE’s Office of Environmental Management, during a ribbon-cutting at WIPP just before the new year, the spinning teeth of a multiton mechanical mining machine clawed through the ceremonial ribbon and began cutting the new Panel 11 out of the site’s 250-million-year-old layer of salt.

Panel 11 is the first of two waste emplacement panels approved last year by the New Mexico Environment Department as part of a 10-year extension of WIPP’s operating permit. The new panel does not represent an increase in the scope for WIPP; the waste to be emplaced in Panel 11 is within original congressional volume limits established for the waste repository.

“The successful start to mining Panel 11 was a great demonstration of how open dialogue and communication with our regulators and stakeholders, along with the support of the field office team, can help mission success,” said Michael Gerle, environmental regulatory compliance director for DOE-EM’s Carlsbad Field Office, which oversees WIPP.

Working the salt mines: Approximately 120,000 tons of salt rock is mined to create a panel, which consists of seven rooms where TRU waste packages are emplaced. Each room measures 300 feet long by 33 feet wide by 14 feet high. It takes about two years to cut and outfit a panel.

Workers are currently emplacing waste into WIPP Panel 8. Panel 8’s first room, Room 7, has been filled, and emplacement activities have moved to Room 6.

Panel 11 is connected to the rest of the WIPP facility by new pathways that stretch nearly half a mile to the west from the existing mine, connecting not only the new panels but a new air intake shaft that is key to increased underground ventilation.

Mining crews use a large continuous miner that cuts into the salt rock with a rotating drum, which can be elevated. Standing behind this cutting head, an operator remotely controls the machine, which has the capacity to generate 10 tons of salt per minute. Gathering arms move the salt onto a belt that carries it to a truck for use elsewhere in the underground or to a hoist that carries the salt from 2,150 feet underground to a salt tailings pile on the surface.

Mining at WIPP is timed so that a panel is only ready when it is needed for waste emplacement. This is because the natural movement of salt causes mined openings to close. In fact, panels are mined slightly larger than the desired size to account for this closure. This salt rock behavior will eventually permanently encapsulate the waste.