DOE 2000. - Waste Isolation Pilot Plant - U.S. Department of Energy

WIPP RH PSAR DOE/WIPP-03-3174 CHAPTER 4
4.3.2.2 Cask Unloading Room
The 72B road cask is moved from the cask preparation station into the CUR. The CUR 25-ton crane
with a road cask lift fixture engages the two opposing lifting trunnions of the road cask. The 25-ton
crane lifts the road cask from the road cask transfer car and positions it over the CUR shield valve.
Interlocks require the 25-ton crane to be positioned over the floor shield valve, the shuttle car cask
receiver (Figure 4.2-17) in the Transfer Cell to be positioned under the floor shield valve, the Transfer
Cell ceiling shield valve to be closed, the Hot Cell shield valve to be closed, and the Hot Cell floor shield
plugs installed before the CUR floor shield valve can be opened. When all interlocks are satisfied, the
floor shield valve is opened. The process is reversed when a 72B road cask is removed from the Transfer
Cell.
Differential air pressure flow from the CUR to the Transfer Cell is used to protect the workers and
prevent the spread of contamination in the case of an off normal event.
4.3.2.3 Transfer Cell
The Transfer Cell is an exclusion area when a canister of RH TRU waste is present, and any reentry after
RH TRU waste handling requires a radiological survey of the cell area.
The loaded 72B cask is lowered through the open CUR shield valve port into the Transfer Cell, then into
the shuttle car road cask receiver. The height of the cask receiver and the size of the shuttle car prevents
any road cask movement once it is inside the receiver. The road cask lift fixture is disengaged from the
lifting trunnions (closed circuit TV cameras and load cells on the lift fixture are used to verify lift fixture
disengagement). The 25-ton crane lift fixture is lifted back inside the CUR. When the open port of the
floor shield valve is clear, the floor shield valve is closed.
The transfer cell shuttle car is designed to transfer one 72B cask from below the CUR floor shield valve
to the various robotic work stations in the Transfer Cell. Remote controlled CCTV cameras are used to
monitor waste handling operations in the Transfer Cell.
The shuttle car positions the72B cask next to the robotic inner lid bolts detensioning device. The
detensioning device loosens the lid retaining bolts, which are spring loaded so that they remain in the lid.
The shuttle car then positions the 72B cask directly below the Transfer Cell shield valve.
4.3.2.4 Facility Cask Loading Room
In the Facility Cask Loading Room, the facility cask, on the facility cask transfer car, has been positioned
so that when it is rotated to the vertical position by the facility cask rotating device, it is in alignment
with the opening of the Transfer Cell ceiling shield valve and the telescoping port shield. The Facility
Cask Loading Room shield door is closed.
When the facility cask has been rotated to the vertical position, the telescoping port shield, mounted in
the floor of the Facility Cask Loading Room, is raised to mate with the facility cask bottom shield valve
body. The Facility Cask Loading Room 6.25-ton grapple hoist is lowered so that the shield bell is in
contact with the facility cask top shield valve body. With the shield bell and the telescoping port shield
in contact with the facility cask, a totally shielded volume is formed to allow the safe transfer of a RH
TRU waste canister from the 72B cask into the facility cask.
4.3-2 January 28, 2003