ML24102A162

NRC Presentation on Reviews of Final Status Survey Reports Given at the March 27, 2024, Public Meeting with OPPD on Fort Calhoun Station Unit 1 Submittal of Phase I Final Status Surveys – (License No. DPR-40, Docket No. 50-285)

ML24102A162
Person / Time
Site:	Fort Calhoun
Issue date:	03/18/2024
From:	Gregory Chapman Reactor Decommissioning Branch
To:
References
Download: ML24102A162 (12)

Text

Final Status Survey Report Reviews

Final Status Survey Report (FSSR). The results of the final status survey conducted by a licensee to demonstrate the radiological status of its facility. The FSSR is submitted to the NRC for review and approval. (NUREG-1757, Vol 2)

NUREG-1757, Vol 2 Guidance on FSSRs

The purpose of the NRC staff review is to verifythat the results of the FSS demonstrate that the site, area, or building meets the radiological criteria for license termination.

Section 4.5.1.1.3 Information to be submitted Section 4.5.1.2.1Minimal Technical Review Section 4.5.1.2.2Detailed Technical Review Section 4.5.1.2.4 Detailed Review Topics Section 4.5.1.3 Evaluation Criteria NRC FSSR Review: Land Areas

For Typical Open Land Survey Units, it includes:

• Use Chapter 5 of LTP as a reference

• Review summary of variations from LTP and survey plans/justification for changes

• Review summary of significant events/investigations performed/judgmental sampling

• Random verification of transcribed values of datum from laboratory reports

• Instruments

• Can measure all ROCs/Surrogates

• Surrogate DCGL determination

• Calibration/efficiency determination

• MDCs 10%-50% of DCGLs

• Verification of surveyplanning

• basis for # of measurements

• scan MDC determination

• survey unit size

• Review confirmatory survey data, if performed, to verify agreement with FSS

• Review inspection reports for the FSS period to verify no findings regarding survey conduct NRC FSSR Review: Land Areas, Continued

Review of results with special attention given to:

• Scanning coverage and exceedance of investigation levels

• Biased sampling/exceedances of the DCGLW

• (bounded/investigated, location, DCGLEMC, etc.)

• How the SOF is determined, including:

• all ROCs considered

• operational vs base-line DCGL values used

• insignificant contributors considered

• surrogate DCGLs determined correctly

• background/reference materials

• negative values

• non-conservative biases present in data

• Verify statistical tests outcomes, if needed

• Does FSS data verify the survey plan (e.g., compare relative shift based on FSS data vs relative shift used for planning FSS)

• QA/QC: verify insignificant contributors and surrogate ratios are appropriate, review duplicate and replicate evaluations to see if in agreement

• Verify all appropriate media considered (GW, small structures, piping, soil, etc.) for demonstration of compliance

NRC FSSR Review: Structures

For Typical Structural Survey Units, it includes (similar to Open Land survey units):

• Use Chapter 5 of LTP as a reference

• Review summary of variations from LTP and survey plans/justification for changes

• Review summary of significant events/investigations performed/judgmental sampling

• Random verification of transcribed valuesof datum from laboratory/survey reports

• Instruments

• Can measure all ROCs/Surrogates

• Gross or Surrogate DCGL determination

• Calibration/efficiency determination

• MDCs 10%-50% of DCGLs

• Verification of survey planning

• basis for # of measurements

• scan MDC determination

• survey unit size

• Review confirmatory survey data, if performed, to verify agreement with FSS

• Review inspection reports for the FSS period verifying no findings concerning survey conduct NRC FSSR Review: Structures, Continued

• Review of results with special attention given to:

• Scanning area coverage

• Review measurements taken

• How background addressed

• Non-conservative bias present in the data

• Biased measurements/exceedances of the DCGLW

• Ensure adequately bounded/investigated

• Impact to adjacent survey units

• Verify DCGLEMCdetermination

• Verify statistical tests were performed appropriately, if needed

• Does FSS data support planning for the survey?

• QA/QC: verify insignificant contributors and surrogate or gross activity DCGLWdeterminations are appropriate, review duplicate and replicate evaluations for appropriate agreement

• Subslab soil, piping, and GW addressed?

FSSR Review Continued

• General

• Was sampling done appropriately?

• Subsurface characterized to appropriate depths?

• Were excavations/backfill characterized?

• Did remediation accomplish removal of significant contamination?

• If ISOCS measurements utilized, was appropriate scanning performed to identify and investigate hot spots?

• Was additional remediation beyond the DCGLs required due to ALARA?

• Did surveys indicate DRPs may be a concern?

• Was GW monitoring and dose assessed consistent with LTP/other requirements?

• Are the methods employed during FSS consistent with MARSSIM/NUREG-1757/LTP?

• Ensure the minimal review requirements in NUREG-1757 Vol 2 are met

• RAIs needed to resolve concerns?

• Review issues identified by interveners and stakeholders and allegations to ensure resolution

• For summary at license termination:

• Develop a spreadsheet to note maximum and average levels of residual contamination and potential dose from each survey unit (also allows check against EPA MOU criteria)

• SER to document what staff evaluate/did during review and whether the FSSR adequately demonstrates compliance with 10 CFR 20, Subpart E.

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