Waste Panels and Capacity

WASTE PANELS & CAPACITY

The Waste Isolation Pilot Plant (WIPP) permanently isolates defense-generated transuranic (TRU) waste 2,150 feet below the surface in an ancient salt formation. Large disposal panels are mined out, with each panel consisting of seven rooms. The rooms are 13-feet high, 33-feet wide and 300-feet long, with a 100-foot beam of salt separating each room. The configuration of the repository has eight panels, with four on each side of the main access drifts. Two additional panels are planned. There are four main access drifts used to transport waste to the panels and for ventilation. Once a panel is filled, it is closed, which includes steel bulkheads.

Panels are not mined until right before they are needed for waste emplacement due to the natural movement of salt, which begins to close the opening within a relatively short period of time. It is this property of salt that led to the selection of a salt bed for the WIPP repository, as over time, the salt will completely encapsulate the waste, safely isolating it from the environment. In active portions of the mine, ground control is needed to maintain mined openings. Ground control includes the installation and maintenance of long steel bolts and wire mesh into the roof and walls.

The underground is accessed using one of four vertical shafts. The largest shaft, with a 20-foot diameter, is used to transport employees, equipment and TRU waste to the underground. The waste hoist has a 45-ton capacity and is capable of transporting 75 employees at one time. Access can also be made using the 10-foot diameter salt shaft. The salt hoist is capable of transporting up to 15 employees, but is primarily used for taking eight tons of salt at a time out of the underground for storage on the surface. The final two shafts are air intake, which brings air into the underground, and exhaust, where air exits.