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Appendix G- Detailed Description of Alternative 4: DoEIR1.200I-I t
^ Entombment with Internal and External Waste Disposal Rev. I Draft tl
Redline)Stsikeout
1 process cell drains, but does not rise in the cells. After this operation, any liquid within the
2 canyon would not automatically flow to cell 10.
3
4 Waste placement is not planned for the ventilation tunnel due to limited accessibility of this area.
5 Therefore, the ventilation tunnel would be grouted to eliminate voids in the building structure.
6 Holes would be angle drilled through to canyon's exterior wall to allow access to the ventilation
7 tunnel for grouting. Frec-flowing grout would be pumped through these holes to fill the
8 ventilation tunnel. The grouting would be completed in lifts to allow time for heat dissipation
9 during grout curing. The tunnel is planned to be filled with grout to the maximum extent
10 possible. It is estimated that the ventilation tunnel would require approximately 2,300 m^
11 (3,000 ydP) of grout. During final design, the decision to fill the tunnel should be revisited.
12 Preliminary structural calculations (Smyth 2001) show that the exterior wall of the tunnel may
13 have sufficient strength to withstand later external pressures from fill heights associated with
14 burying the canyon building and, therefore, not require grouting.
15
16 Facility modification would also involve removing and disposing of interfering structures,
17 equipment, and material. During this phase of the work scope, equipment and material removal
18 would be limited to "clean" areas of the 271-U Office Building, the 221-U Facility galleries, and
19 associated storage spaces. 'lltis activity would include the removal of the following:
20
^21 • Installed and fixed equipment
22 • All unattached equipment and components
23 • Abandoned supplies
24 • Materials
25 • Debris.
26
27 These items would be sorted for reuse, recycle, or disposal.
28 G.13.2 Disposal of Contaminated Equipment In 221-U. It is estimated that there isare
29 approximately 5,400 mj (7,000 y&) of contaminated equipment and components (gross loose
30 ^ volume before sizc reduction) currently stoped-on the canyon deck and in the process cells. For
31 Alternative 4, those process cells with legacy equipment having dose rates >100 tntem/hr would
32 be opened only to place size-reduced legacy equipment from the operating deck and emut into
33 them. All of the equipment would be reduced in size and volume and then disposed into the
34 process cells meeting the dose rate criteria (except for cell 3, which would be left unfilled for
35 later equipment or waste placement). Size and volume reduction is necessary so that all of the
36 contaminated equipment would fit into the process cells. Minimizing the amount of size and
37 volume reduction to just the amount of effort required to allow the contaminated equipment to fit
38 into the process cells is desirable because it would limit worker exposure. After size reduction,
39 the estimated volume of equipment from the • an n deck and in the
40 process cells is 3,400 0 (4,400 yd^.
41
(O^N42 Size and volumc reduction would require a disposition plan for each equipment item. If breaking
43 or cutting activities are necessary for disposing of the equipment, the 221-U Canyon Building
Final Feasibility Srudy foe the Canyon Disposition Initiative (221 •U Facility)
1 C-lo
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