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Appendix E - Detailed Description of Alternative 1: DOF/R1.-2001-1I
I Full Removal and Disposal Rev. o raft t;
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1 would be designed for equipment disassembly, dccontamination, and packaging of large items in
2 a controlled environment. Disassembly activities would include mechanical and flame cutting,
3 hydraulic shearing, and manual methods. Additional technologies that could be applied are
4 described in Appendix 1. Equipment and materials would be transferred into and out of the
5 enclosure with the main overhead crane.
6
7 The most significant contribution to worker exposure under Alternative I would be the size
8 reduction and packaging of the contaminated legacy equipment that is currently within the
9 221-U Facility. Estimated worker dose for these activities alone is nearly 200 pcrson-rem (BFA
10 2001a). If all of the legacy equipment is volume reduced for shipment, significant worker time
11 and resulting higherexposures would occur. This activity, even with latest technologies
12 available, would be performed in personal protective equipment-required work areas (i.e.,
13 contaminated areas and airborne areas). Significant engineering controls would be required to
14 reduce worker exposure from external and internal exposure sources. Worker turnover could
15 increase due to harsher working conditions. The preliminary ALARA estimate (BHI 2001 a)
16 considered technology currently available.
17
18 E.19.4 Hot Pipe Trench. After the anvon deck can support work
19 activities, equipment currently stered in the process cells could be prepared for removal. The
20 equipment would require the same level of planning and disposition approach as the eanyon
^21 deck equipment. Based on review of available historical photographs, the
22 hot pipe trench contains small-diameter piping. Piping could be removed by cutting a section
23 free, ensuring it is empty, then crushing the cut ends. It would be removed, size reduced as
24 necessary, wrapped, and placed into the modular containers ready for hauling and disposal at
25 ERDF.
26
27 E.13S Remove Surface Contamination. To safely enter the building during its operational
28 phase in this alternative, contamination survey results would be used to identify where
29 decontamination activities are needed. Contamination would either be removed or fixed to the
30 canyon surface to reduce the dose rate and contamination risk to the lowest possible level. It is
31 assumed that water jet, water blasting, or water flushing are practical on the canyon's interior
32 because the waste water could be collected in cell 10 and disposed of in the 200 Area's Liquid
33 Effluent Remediation Facility. Scarifying may be required on some areas.
34
35 After the building has been surveyed and the contamination removal planned, the work would
36 require scaffolding and wastewater collection systems to be installed and maintained, and
37 disposal of wastewater during and after decontamination.
38
39 E.1.3.6 F'ix Contamination on 221-U Interior Surfaces. It is assumed that surface
40 contamination on the canyon walls, Aeercanyon deck s, and ceiling could be addressed with
41 application of a fxative. Fixative would also be applied to all of the interior surfaces of the pipe
42 trench, process cells, craneway, and vent tunnel.
>'\43
Final Feasibility Siady for rite Canyon Disposirion Initiative (221 •U Faeiliry)
J une 2 00-1 E-9