ALTERNATE APPROACH TO HAZARD CATEGORIZATION FOR SALTSTONE FACILITY AT SRS
The Saltstone Facility at Savannah River Site (SRS) was originally segmented into two segments: the Saltstone Production Facility (SPF) and the Saltstone Disposal Facility (SDF). Based on the inventory of radionuclides available for release the SPF and SDF were categorized as Nonreactor Hazard Category (HC)-3. The hazard categorization recognized the SDF will contain contributions of radionuclides which would exceed the HC-2 Threshold Quantity (TQ) in the form of grout. However it was determined not to impact the facility hazard categorization based on the grout being in a solid, monolithic form which was not easily dispersible. But, the impact of a quantity of unset grout expected to be present at the vault following operation of the process was not addressed. A Potential Inadequacy in Safety Analysis (PISA) was later issued based on the hazard categorization determination for the facility not addressing unset grout. This initiated a re-evaluation of the accident scenarios within the hazards analysis. During this re-evaluation, the segmentation of the facility was challenged based on the potential interaction between facility segments; specifically, the leachate return line and the grout transfer line, which were considered separate segments, are located in close proximity at one point. such that for certain events (NPH as well as External Vehicle Impact) both could be damaged simultaneously and spill contents on the ground that could commingle. This would violate the guideline for segmentation. Therefore, the Hazard Categorization (HC) was reevaluated based on the facility being a single segment and including the additional unset grout as part of total inventory. This total inventory far exceeded the limit for HC-2 TQ and made the facility's initial categorization as HC-2. However, alternative analysis methodology based on credible release fractions allowed in DOE-STD-1027-92 (Ref.1) showed that the Saltstone facility could still be categorized as Hazard Category 3 Nuclear Facility with no segmentation. Since it was the first time any facility at SRS tried this alternate approach safety analyst had to face substantial resistance and reservations from both the facility and local DOE customers which were eventually overcome with approval and acceptance from DOE-HQ.
- Research Organization:
- Savannah River Site (SRS), Aiken, SC (United States)
- Sponsoring Organization:
- USDOE
- DOE Contract Number:
- DE-AC09-96SR18500
- OSTI ID:
- 957312
- Report Number(s):
- WSRC-MS-2009-00035; TRN: US1002287
- Resource Relation:
- Conference: Integrating Safety Into Design
- Country of Publication:
- United States
- Language:
- English
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