ML25078A032
| ML25078A032 | |
| Person / Time | |
|---|---|
| Site: | National Bureau of Standards Reactor |
| Issue date: | 03/21/2025 |
| From: | NRC/NRR/DANU/UNPL |
| To: | |
| Shared Package | |
| ML25078A033 | List: |
| References | |
| Download: ML25078A032 (7) | |
Text
Redefinition of the National Bureau of Standards Reactor (NBSR)
NRC PUBLIC MEETING MARCH 6, 2025
LAR to redefine the NBSR 2
- Non-Power Production or Utilization Facility License Renewal Rule
- Implemented December 30, 2024
- Eliminated License terms for facilities other than Testing Facilities
- Requires 5-year updates of FSAR (regardless of classification)
- Redefined Testing Facility using risk-based approach
- The 20 MW NBSR is the only Testing Facility currently licensed by NRC
- Was made so only by virtue of power level (Previously defined as any facility >10 MW).
NPUF Rule 3
- New Definition of Testing facility - Analyzed accident radiation doses are in excess of 1 rem (0.01 Sv) TEDE for any individual located in the unrestricted area
- The relevant accident analyzed for this dose is the Maximum Hypothetical Accident (MHA), given in NBSR SAR section 13.2.1
Total MHA public dose:
0.0064 Rem 0.6% of the dose specified to meet the definition of Testing Facility NBSR Maximum Hypothetical Accident 4
Doses (in mrem) to a person standing at the edge of the exclusion zone (400m) 0-2 Hours 2-24 Hours 1-30 Days Total Radiation from fission product decay Direct 0.0 0.0 0.1 0.1 Sky Shine 0.0 0.0 0.2 0.2 Total 0.0 0.0 0.3 0.3 Iodine Releases CEDE1 0.0 0.0 0.0 0.0 Thyroid 0.0 0.1 0.0 0.1 Noble Gas Cloud (max)
Slightly Stable Conditions2 1.0 3.4 2.0 6.4 1 The dose given is the maximum Committed Effective Dose Equivalent (CEDE) at a point on or outside the 400 m boundary.
2 The wind speed is assumed constant at 1 m/s, with allowance for meandering (averaged over 120 min) but no wind shifts, Pasquill diffusion category E. The dose due to the cloud outside the boundary is then a maximum for this stability condition. However, such conditions could not persist for even 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br />, so these numbers are large over-estimates. Actual doses would be 2-100 times lower.
NBSR SAR Table 13.4
Submittal will include summary of MHA analyses, including Table 13.4, demonstrating that projected public doses fall well below the 1 rem specified in 50.34(a)(1)(i)
There are no other changes requested, including SAR or Technical Specification changes.
What other information does NRC need?
NCNR Submittal 5
Will reclassify the NBSR as a research reactor instead of Testing Facility Will eliminate license expiration term (current expiration is July, 2029)
Still requires FSAR updates and evaluation of reactor conditions, including aging Impact of License Amendment 6