closure project manager - Document Request - U.S. Department of ...

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FACILITY OVERWEW
The Building 991 Complex is located on the east side of the developed portion of the Site
within the Protected Area. The complex is composed of several facilities of which Building 99 1
is the main building. Four buildings are connected to Building 991 and are underground vaults
These buildings are: (1) Building 996 which is connected to Building 991 via Corridor B,
(2)Building997 which is connected to CorridorB via CorridorC and is prohibited from
container storage by the TSRs; (3) Building 998 (also called Room 300) which is connected to
Building 991 via Corridor A; and (4) Building 999 which is connectedt to Corridor C and is also
prohibited from container storage. Four other major buildings are within the complex.
(1) Building 984 which is a warehouse-type facility used for storing empty shipping containers
and contains a drum crushing operation; (2) Building 985 which is the Heating, Ventilating, and
Air Conditioning (HVAC) plenum building supporting Building 996, Building 997, and
Building999; (3)Building 989 which is the standby power diesel generator facility; and
(4)Building992 which is a normally unoccupied guard facility. All of the above ground
facilities are located in a depression'(i.e., below surrounding landscape) except for Building 985
which is located near the top of the north rise above Corridor B and Building 996.
FACEITY HAZARD CLASSIFICATION
The Building 991 Complex was previously classified as a moderate hazard facility per
DOE Order 5481.1B (Ref. 8) and a nonreactor nuclear facility per DOE Order 5480.5 (Ref. 9)
Based upon the inventory of radionuclides present during the accomplishment of the new
mission of the Building 991 Complex, the complex is now classified as a Hazard Category 2 I
nuclear facility in accordance with the inventory thresholds defmed in Attachment 1 of
DOE-STD-1027-92.
SAFETYANALYSIS OYERVTEW
An activity-based hazards identification and evaluation of the Building 991 Complex was
performed to identifj, evaluate, and control hazards associated with SNM and waste container
receipt, storage or staging, transfer and shipping operations. The hazard identification process
identifed 44 hazards or energy sources in the Building 991 Complex. Of these, 22 hazards or
energy sources were determined to be standard industrial hazards that were to be controlled by
the Site Safety Management Programs (SMPs) and did not require further evaluation. For the
remaining 22 hazarddenergy sources, the hazard evaluation process determined how each of the
hazards or energy sources could lead to a release of hazardous material. The process identified
37general accident scenarios leading to releases due to failures of radioactive material
containers. These 37 general accident scenarios could be grouped into seven accident scenario
categories. The seven postulated accident categories initially considered for evaluation were
(1) material fires (i.e., pyrophoric material fues); (2) facility fires; (3) spills; (4) punctures,
(5) container explosions @e., internal hydrogen explosions); (6) facility explosions; and
(7) criticality events.
Each of the 37general accident scenarios were evaluated for each of the identified
radioactive material containers (i.e., SNM Type B shipping containers, POCs, TRU waste
containers, metal LLW containers, and wooden LLW crates) under each of the general activities
to be performed in the complex using a hazard evaluation process consistent with that defmed in
Revision 1
Smtcmher 1'9930
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Building 991 Complex MAR
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