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Appendix F -Detailed Description of Alternative 3: DOEAR1,2001-11
I Entombment with Internal Waste Disposal Rev. p l Draft 0
Rcdlinc/Slrikcout
I contamination present in the pipe. After the connecting pipes to cell 10 are sealed, grout would be
2 pumped in from both ends of the cell drain header. Because the cell drain header flows
3 downward from the building ends toward cell 10, a liquid-consistency grout would flow through
4 the header and require very little pumping pressure. Drainage openings in each process cell
5 would act as air vents, and the pressure would be regulated so that the grout would be visible in
6 the process cell drains, but would not rise in the cells. After this operation, any liquid within the
7 canyon would not automatically flow to cell 10.
9 Waste placement is not planned for the ventilation tunnel due to limited accessibility of this area.
10 Therefore, the ventilation tunnel would be grouted to eliminate voids in the building structure.
I 1 Holes would be angle drilled through to canyon's exterior wall to allow access to the ventilation
12 tunnel for grouting. Free-flowing grout would be pumped through these holes to 6ll the
13 ventilation tunnel. The grouting would be completed in lifts to allow time for heat dissipation
14 during grout curing. The tunnel is planned to be filled with grout to the maximum extent
15 possible. It is estimated that the ventilation tunnel would require approximately 2,300 m3
16 (3,000 ydP) of grout. During final design, the decision to fill the tunnel should be revisited.
17 Preliminary structural calculations (Smyth 2001) show that the exterior wall of the tunnel may
18 have sufficient strength to withstand later external pressures from fill heights associated with
19 burying the canyon building and, therefore, not require grouting.
20
('_^'21 Facility modification would also involve removing and disposing of interfering structures,
22 equipment, and material. During this phase of the work scopc, equipment and material removal
23 would be limited to "clean" areas of the 271-U Office Building, the 221-U Facility galleries, and
24 associated storage spaces. This activity would include the removal of the following:
25
26 • Installed and fixed equipment
27 • All unattached equipment and components
28 • Abandoned supplies
29 • Materials
30 • Debris.
31
32 These Items would be sorted for reusc, recycle, or disposal.
33
34 F.13.2 Disposal or Contaminated Equipment In 221-U. It is estimated that there+sare
35 approximately 5,400 m3 (7,000 yd3) of contaminated equipment and components (gross loose
36 volume before size reduction) currently steredon the canyon deck and in the process cells. For
37 Alternative 3, those process cells with legacy equipment having dose rates >100 mrem/hr would
38 be opened only to place size-reduced legacy equipment from the operating deck and erout into
39 them. All of the equipment would be reduced in size and volume and then disposed into the
40 process cells meeting the dose rate criteria (except for cell 3, which would be left unfilled for
41 later equipment or waste placement). Size and volume reduction would be necessary so that all
/-^42 of the contaminated equipment would fit into the process cells. Minimizing the amount of size
1 43 and volume reduction to just the effort required to allow the contaminated equipment to fit into
44 the process cells would be desirable because it would limit worker exposure. After size -
F(nal^Feas(6tfity
Study jor the Canyon Ditposition hdtiatlve (22l •U Facifity)
Ju n e
F-10