ML20006D507

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Lacrossesolutions, LLC - Final Status Survey Report - Phase 2, Crib House, Survey Unit B2-010-101
ML20006D507
Person / Time
Site: La Crosse  File:Dairyland Power Cooperative icon.png
Issue date: 12/12/2019
From: Yetter R
LaCrosseSolutions
To:
Office of Nuclear Material Safety and Safeguards
Shared Package
ML20006D756 List:
References
LC-2019-0051 B2-010-101
Download: ML20006D507 (40)
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Text

LA CROSSE BOILING WATER REACTOR FINAL STATUS SURVEY RELEASE RECORD LACBWR CRIB HOUSE SURVEY UNIT B2-010-101

12/12/2019 FSS RELEASE RECORD LACBWR CRIB HOUSE SURVEY UNIT B2-010-101 TABLE OF CONTENTS

1. EXECUTIVE

SUMMARY

................................................................................................................................. 5

2. SURVEY UNIT DESCRIPTION ....................................................................................................................... 5
3. CLASSIFICATION BASIS ................................................................................................................................. 6
4. DATA QUALITY OBJECTIVES (DQO) .......................................................................................................... 7
5. SURVEY DESIGN ............................................................................................................................................... 9
6. SURVEY IMPLEMENTATION ...................................................................................................................... 13
7. SURVEY RESULTS .......................................................................................................................................... 14
8. QUALITY CONTROL ...................................................................................................................................... 17
9. INVESTIGATIONS AND RESULTS .............................................................................................................. 18
10. REMEDIATION AND RESULTS ................................................................................................................... 18
11. CHANGES FROM THE FINAL STATUS SURVEY PLAN ........................................................................ 18
12. DATA QUALITY ASSESSMENT (DQA) ....................................................................................................... 18
13. ANOMALIES ..................................................................................................................................................... 19
14. CONCLUSION .................................................................................................................................................. 19
15. REFERENCES................................................................................................................................................... 19
16. ATTACHMENTS .............................................................................................................................................. 20 ATTACHMENT 1 - FIGURES AND MAPS ............................................................................................................. 21 ATTACHMENT 2 - SCAN DATA ............................................................................................................................. 24 ATTACHMENT 3 - SIGN TEST ............................................................................................................................... 26 ATTACHMENT 4 - QUALITY CONTROL ASSESSMENT ...................................................................................... 28 ATTACHMENT 5 - GRAPHICAL PRESENTATIONS ............................................................................................. 30 ATTACHMENT 6 - LUDLUM 2350-1 DOWNLOAD REPORTS ............................................................................ 34 2

FSS RELEASE RECORD LACBWR CRIB HOUSE SURVEY UNIT B2-010-101 LIST OF TABLES Table 3 Static Measurements for Characterization of Above Grade Buildings ............................................... 6 Table 3 Summary Statistics for Characterization of Above Grade Buildings .................................................. 6 Table 4 Dose Significant Radionuclides and Mixture for Above Grade Buildings ........................................... 8 Table 4 Base Case DCGLs for Above Grade Buildings (DCGL AGB) .................................................................. 9 Table 4 Operational DCGLs for Above Grade Buildings (OpDCGLAGB) ......................................................... 9 Table 5 Survey Unit B2-010-101 Measurement Designations........................................................................... 12 Table 5 Investigation Levels ................................................................................................................................ 13 Table 5 Synopsis of Survey Design...................................................................................................................... 13 Table 7 Synopsis of Scan Results ........................................................................................................................ 15 Table 7 Detector Efficiencies ............................................................................................................................... 16 Table 7 Summary of Systematic, Judgmental, and QC Static Measurements ................................................ 16 Table 7 Basic Statistical Properties of Systematic Measurement Population .................................................. 17 Table 16 Survey Unit B2-010-101 Complete Scan Data .................................................................................... 25 Table 16 Survey Unit B2-010-101 Sign Test ....................................................................................................... 27 Table 16 Survey Unit B2-010-101 QC Assessment ............................................................................................ 29 LIST OF FIGURES Figure 16 Survey Unit B2-010-101 Systematic and Judgmental Measurement Locations Map (Exterior) . 22 Figure 16 Survey Unit B2-010-101 Systematic and Judgmental Measurement Locations Map (Interior) .. 23 Figure 16 Quantile Plot for Gross Activity ........................................................................................................ 31 Figure 16 Histogram for Gross Activity ............................................................................................................. 32 Figure 16 Retrospective Power Curve ................................................................................................................ 33 3

FSS RELEASE RECORD LACBWR CRIB HOUSE SURVEY UNIT B2-010-101 LIST OF ACRONYMS AND ABBREVIATIONS ALARA As Low As Reasonably Achievable ASP Alarm Set Point DQA Data Quality Assessment DQO Data Quality Objective DCGL Derived Concentration Guideline Level DCGLAGB Above Grade Building Derived Concentration Guideline Level FSS Final Status Survey GPS Global Positioning System G-1 Genoa 1 HSA Historical Site Assessment IC Insignificant Contributors LACBWR La Crosse Boiling Water Reactor LBGR Lower Bound of the Gray Region LTP License Termination Plan MARSSIM Multi-Agency Radiation Survey and Site Investigation Manual MDC Minimum Detectable Concentration MDCR Minimal Detectable Count Rate OpDCGLAGB Above Grade Building Operational Derived Concentration Guideline Level QAPP Quality Assurance Project Plan QC Quality Control ROC Radionuclides of Concern SOF Sum-of-Fraction TEDE Total Effective Dose Equivalent UBGR Upper Bound of the Gray Region UCL Upper Confidence Limit URS Unconditional Release Survey USNRC Unites States Nuclear Regulatory Commission 4

FSS RELEASE RECORD LACBWR CRIB HOUSE SURVEY UNIT B2-010-101

1. EXECUTIVE

SUMMARY

This Final Status Survey (FSS) Release Record for survey unit B2-010-101, LACBWR Crib House, has been generated in accordance with LaCrosseSolutions procedure LC-FS-PR-009, Final Status Survey Data Reporting (Reference 1) and satisfies the requirements of Section 5.11 of the La Crosse Boiling Water Reactor License Termination Plan (LACBWR LTP) (Reference 2).

An FSS sample plan for this survey unit was developed in accordance with LaCrosseSolutions procedures LC-FS-PR-015, Final Status Surveys for Structures (Reference 3) and LC-FS-PR-002, Final Status Survey Package Development (Reference 4), the LACBWR LTP, and with guidance from NUREG-1575, Revision 1, Multi-Agency Radiation Survey and Site Investigation Manual (MARSSIM) (Reference 5).

This above grade building survey unit has a MARSSIM classification of 2. A survey plan was designed based upon use of the Sign Test as the nonparametric statistical test for compliance. Both the Type I () and Type II () decision error rates were set at 0.05. As a systematic measurement population, twenty-eight (28) static beta measurements were acquired from the survey unit. In addition, surface scanning was performed on approximately 30% of the total surface area in the survey unit. The data assessment results for survey unit B2-010-101 indicate that the maximum gross activity among systematic measurements is equal to 1,732 dpm/100 cm2, which is 54.79% of the Adjusted Gross Operational Derived Concentration Guideline Level (DCGL) for above grade buildings (see Section 5 of this release record for the calculations of adjusted gross DCGLs). Therefore, the null hypothesis of the Sign test is rejected, and survey unit B2-010-101 is acceptable for unrestricted release. The mean gross activity among systematic measurements is equal to 401 dpm/100 cm2, which is 2.03% of the Adjusted Gross Base Case DCGL. Multiplying this fraction by 25 mrem/yr results in a dose for the survey unit of 0.5081 mrem/yr.

2. SURVEY UNIT DESCRIPTION Survey Unit B2-010-101 is an impacted Class 2 above grade building survey unit. The survey unit consists of the interior and exterior surfaces of the LACBWR Crib House. The LACBWR Crib House provided circulating water for the condenser and service water systems. The LACBWR Crib House measures 14.5 m long by 11 m wide by 6 m high, which equates to a total surface area of 1,060 m2. Refer to Attachment 1 of this report for figures and maps depicting survey unit B2-010-101.

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FSS RELEASE RECORD LACBWR CRIB HOUSE SURVEY UNIT B2-010-101

3. CLASSIFICATION BASIS Based on the La Crosse Boiling Water Reactor Historical Site Assessment (HSA)

(Reference 6), survey unit B2-010-101 was identified as a Class 2 structure survey unit. The following summarizes the results of the characterization surveys for seven (7) of the above grade buildings to be left on-site upon termination of the license.

The characterization surveys for the above grade buildings were conducted between November 8, 2016, and November 18, 2016. In total, fifty-six (56) static beta measurements were collected in the buildings (eight [8] in each of seven [7] buildings). No measurements exceeded their respective action levels. A summary of the static measurements are presented in Table 3-1. The summary statistics for the characterization data are provided in Table 3-2.

Table 3 Static Measurements for Characterization of Above Grade Buildings Static Beta Measurements (dpm/100 cm2)

Transmission Back-Up LACBWR G-3 Crib Sub-Station Barge Wash G-1 Crib Security Control Crib House House Switch Break Room House Station Center House 313 1,264 588 213 0 751 0 13 13 363 226 38 0 150 0 38 0 0 0 0 0 1,702 26 88 889 0 1,514 0 138 0 0 376 0 0 38 0 450 0 238 0 551 100 0 100 0 0 163 438 225 0 2,203 651 0 0 1,089 13 Table 3 Summary Statistics for Characterization of Above Grade Buildings Standard Mean Median Minimum Maximum Deviation (dpm/100 cm2) (dpm/100 cm2) (dpm/100 cm2) (dpm/100 cm2) (dpm/100 cm2) 267 32 0 2,203 473 Based upon review of the historical information, the results of the characterization survey data, and completion of a final Survey Unit Classification Worksheet, the correct final classification of survey unit B2-010-101 was determined to be Class 2.

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FSS RELEASE RECORD LACBWR CRIB HOUSE SURVEY UNIT B2-010-101

4. DATA QUALITY OBJECTIVES FSS planning and design relies on a properly executed Data Quality Objective (DQO) process to ensure, through compliance with explicitly defined inputs and boundaries, that the primary objective of the survey is satisfied. The DQO process, utilized in accordance with MARSSIM, is described in the LACBWR LTP. The appropriate design for a given survey was developed using the DQO process as outlined in Appendix D of MARSSIM.

The DQO process incorporated hypothesis testing and probabilistic sampling distributions to control decision errors during data analysis. Hypothesis testing is a process based on the scientific method that compares a baseline condition to an alternate condition. The baseline condition is technically known as the null hypothesis. Hypothesis testing rests on the premise that the null hypothesis is true and that sufficient evidence must be provided for rejection. In designing the survey plan, the underlying assumption, or null hypothesis was that residual activity in the survey unit exceeded the release criteria. Rejection of the null hypothesis would indicate that residual activity within the survey unit does not exceed the release criteria. Therefore, the survey unit would satisfy the primary objective of the FSS sample plan.

The primary objective of the FSS sample plan is to demonstrate that the level of residual radioactivity in survey unit B2-010-101 did not exceed the release criteria specified in the LTP and that the potential dose from residual radioactivity is As Low As Reasonably Achievable (ALARA).

LaCrosseSolutions TSD RS-TD-313196-001, Radionuclides of Concern during LACBWR Decommissioning (Reference 7) established the basis for an initial suite of potential ROC for decommissioning. Insignificant contributors (IC) were determined consistent with the guidance contained in Section 3.3 of NUREG-1757, Volume 2, Revision 1, Consolidated Decommissioning Guidance - Characterization, Survey, and Determination of Radiological Criteria, Final Report (Reference 8). In all soil and concrete scenarios, Cs-137, Co-60, Sr-90, Eu-152 and Eu-154 contribute nearly 100% of the total dose. The remaining radionuclides were designated as IC and were eliminated from further detailed evaluation. Therefore, the final ROCs for LACBWR above grade buildings, soil, basement concrete, and buried piping are Cs-137, Co-60, Sr-90, Eu-152 and Eu-154.

The LTP, Section 6.14.1 discusses the process used to derive the ROC for the decommissioning of LACBWR, including the elimination of IC from the initial suite.

Table 4-1 presents the ROC for the decommissioning of above grade buildings at LACBWR and the normalized mixture fractions based on the radionuclide mixture.

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FSS RELEASE RECORD LACBWR CRIB HOUSE SURVEY UNIT B2-010-101 Table 4 Dose Significant Radionuclides and Mixture for Above Grade Buildings Fraction of Total Activity Radionuclide (normalized)(1)

Co-60 0.0644 Sr-90 0.0981 Cs-137 0.829 Eu-152 0.00549 Eu-154 0.00281 (1) Based on maximum percent of total activity from Table 22 of RS-TD-313196-001, normalized to one for the dose significant radionuclides.

The LTP, Section 5.2 states that each radionuclide-specific Base Case DCGL is equivalent to the level of residual radioactivity (above background levels) that could, when considered independently, result in a Total Effective Dose Equivalent (TEDE) of 25 mrem/yr to an Average Member of the Critical Group. To ensure that the summation of dose from each source term is 25 mrem/yr or less after all FSS is completed, the Base Case DCGLs are reduced based on an expected, or a priori, fraction of the 25 mrem/yr dose limit from each source term. The reduced DCGLs, or Operational DCGLs, can be related to the Base Case DCGLs as an expected fraction of dose based on an a priori assessment of what the expected dose should be based on the results of site characterization, process knowledge, and the extent of planned remediation. The Operational DCGL is then used as the DCGL for the FSS design of the survey unit (calculation of surrogate DCGLs, investigations levels, etc.).

Details of the Operational DCGLs derived for each dose component and the basis for the applied a priori dose fractions are provided in LC-FS-TSD-002, Operational Derived Concentration Guideline Levels for Final Status Survey (Reference 9).

At LACBWR, compliance is demonstrated through the summation of dose from five (5) distinct source terms (i.e., basements, soils, buried pipe, above grade buildings, and groundwater) for the end-state. When applied to above grade buildings, the DCGLs are expressed in units of activity per surface area (dpm/100 cm2).

The Screening Values in NUREG-1757, Volume 2, Revision 1, Consolidated Decommissioning Guidance - Characterization, Survey, and Determination of Radiological Criteria, Final Report, Table H-1, are applied to the FSS of above grade buildings. The Table H-1 Screening Values are presented as Base Case DCGLs (equivalent to 25 mrem/yr) and are reproduced in Table 4-2 below.

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FSS RELEASE RECORD LACBWR CRIB HOUSE SURVEY UNIT B2-010-101 Table 4 Base Case DCGLs for Above Grade Buildings (DCGLAGB)

DCGLAGB Radionuclide (dpm/100cm2)

Co-60 7,100 Sr-90 8,700 Cs-137 28,000 Eu-152 12,700 Eu-154 11,500 The Operational DCGLs are then used as the DCGL for the FSS design of the survey unit (calculation of surrogate DCGLs, investigation levels, etc.). The Operational DCGLs for the unrestricted release of above grade buildings are provided in Table 4-3.

Table 4 Operational DCGLs for Above Grade Buildings (OpDCGLAGB)

OpDCGLAGB Radionuclide (dpm/100cm2)

Co-60 1,136 Sr-90 1,392 Cs-137 4,480 Eu-152 2,032 Eu-154 1,840 Instrument DQOs included a verification of the ability of the survey instrument to detect the radiation(s) of interest relative to the Operational DCGL. Survey instrument response checks were required prior to issuance and after the instrument had been used. Control and accountability of survey instruments was required to assure the quality and prevent the loss of data. The minimum acceptable MDC for measurements obtained using field instruments was 50% of the applicable Operational DCGL.

5. SURVEY DESIGN The level of effort associated with planning a survey is based on the complexity of the survey unit and nature of the hazards. Guidance for preparing FSS plans is provided in procedures LC-FS-PR-015, Final Status Surveys for Structures and LC-FS-PR-002, Final Status Survey Package Development.

For the FSS of above grade buildings, Adjusted Gross DCGLs are calculated. This is done 9

FSS RELEASE RECORD LACBWR CRIB HOUSE SURVEY UNIT B2-010-101 because radionuclide-specific data is not acquired with static measurements. The equation for calculating the Adjusted Gross DCGL is as follows:

Equation 1 1

=

1 2

[( ) + ( ) + ( )]

1 2 Where: DCGLAG = Adjusted Gross DCGL in units of dpm/100 cm2 DCGLi = Gross DCGL for detectable radionuclide in units of dpm/100 cm2 fi = Mixture fraction of detectable radionuclides Using Equation 1, and values within Tables 4-1 and 4-3, the Adjusted Gross Operational DCGL was calculated as follows:

Equation 2 1

=

0.0644 0.0981 0.829 0.00549 0.00281

[(1136 ) + (1392 ) + (4480 ) + (2032 ) + (1840 )]

(60) (90) (137) (152) (154)

= 3160 /100 2 The Adjusted Gross Operational DCGL was calculated as 3,160 dpm/100 cm2, which was the action level for survey unit B2-010-101.

Using Equation 1, and values within Tables 4-1 and 4-2, the Adjusted Gross Base Case DCGL was calculated as follows:

Equation 3 1

=

0.0644 0.0981 0.829 0.00549 0.00281

[(7100 )+( )+( )+( )+( )]

(60) 8700 (90) 28000 (137) 12700 (152) 11500 (154)

= 19751 /100 2 The Adjusted Gross Base Case DCGL was calculated as 19,751 dpm/100 cm2. The mean activity from the FSS systematic measurements is compared to the Adjusted Gross Base Case DCGL, and the dose contribution from the survey unit is calculated.

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FSS RELEASE RECORD LACBWR CRIB HOUSE SURVEY UNIT B2-010-101 The Sign test was selected as the nonparametric statistical test for compliance with the release criteria. The number of measurements for use with the Sign test was determined in accordance with procedures LC-FS-PR-002 and LC-FS-PR-015. The relative shift (/) for the survey unit data set is defined as shift (), which is the Upper Boundary of the Gray Region (UBGR), or the DCGL, minus the Lower Bound of the Gray Region (LBGR),

divided by sigma (), which is the standard deviation of the data set used for survey design.

The optimal value for / should range between one (1) and three (3). The largest value the

/ can have is three (3). If the calculated value of / exceeds three (3), an adjusted value of three (3) will be used for /. The / for survey unit B2-010-101, based on the amalgamated gross measurement data from characterization of the LACBWR above grade buildings to remain at license termination, was calculated as follows:

Equation 4

/ = 1580/473 = 3.34 As the calculated relative shift was greater than three (3), a value of three (3) was used as the adjusted /. Both the Type I error (i.e., value) and the Type II error (i.e., value) was set at 0.05. The sample size from Table 5.5 of MARSSIM that equates to the Type I and Type II error of 0.05 for use with the Sign test is an N value of fourteen (14). Twenty-eight (28) total systematic measurements (14 interior and 14 exterior) were included in the survey design for survey unit B2-010-101. This was done because the total surface area of the survey unit surpasses the recommended Class 2 structure survey unit size from Table 1 in MARSSIM. The survey unit consisted of both interior and exterior measurements, with 14 required compliance measurements each, to accommodate the MARSSIM recommended survey unit size restrictions.

A Prospective Power Curve was generated using COMPASS, a software package developed under the sponsorship of the United States Nuclear Regulatory Commission (USNRC) for implementation of the MARSSIM in support of the decommissioning license termination rule (10CFR20, Subpart E). The result of the COMPASS computer run showed adequate power for the survey design.

As the survey unit was designated Class 2, measurement locations were selected based on a systematic grid with a random starting point. The systematic locations of the static measurements were selected using Visual Sample Plan (VSP). Input parameters included the use of survey unit drawings and the systematic sampling tool set with a predetermined number of measurement locations. The systematic measurement locations were identified in the field using dimension parameters provided on the survey unit map (see Attachment 1). Table 5-1 lists the systematic, judgmental, and QC measurements collected for FSS of survey unit B2-010-101.

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FSS RELEASE RECORD LACBWR CRIB HOUSE SURVEY UNIT B2-010-101 Table 5 Survey Unit B2-010-101 Measurement Designations Measurement ID B2-010-101-FSWM-A01-BD B2-010-101-FSWM-B01-BD B2-010-101-FSWM-A02-BD B2-010-101-FSWM-B02-BD B2-010-101-FSRC-A03-BD B2-010-101-FSCM-B03-BD B2-010-101-FSWM-A04-BD B2-010-101-FSWM-B04-BD B2-010-101-FSWM-A05-BD B2-010-101-FSCM-B05-BD B2-010-101-FSRC-A06-BD B2-010-101-FSWM-B06-BD B2-010-101-FSRC-A07-BD B2-010-101-FSFM-B07-BD B2-010-101-FSWM-A08-BD B2-010-101-FSCM-B08-BD B2-010-101-FSWM-A09-BD B2-010-101-FSFM-B09-BD B2-010-101-FSRC-A10-BD B2-010-101-FSWM-B10-BD B2-010-101-FSRC-A11-BD B2-010-101-FSCM-B11-BD B2-010-101-FSWM-A12-BD B2-010-101-FSWM-B12-BD B2-010-101-FSWM-A13-BD B2-010-101-FSFM-B13-BD B2-010-101-FSWM-A14-BD B2-010-101-FSWM-B14-BD B2-010-101-FJWM-A15-BD B2-010-101-FJFM-B15-BD B2-010-101-FQWM-A01-BD B2-010-101-FQCM-B05-BD The implementation of quality control measures as referenced in LTP, Section 5.9 and LaCrosseSolutions LC-QA-PN-001, Final Status Survey Quality Assurance Project Plan (QAPP) (Reference 10) includes the collection of a replicate measurement on 5% of the measurements collected in a survey unit, with the locations selected at random. Two (2) replicate measurements, B2-010-101-FQWM-A01-BD and B2-010-101-FQCM-B05-BD, were selected at random for the QC replicate measurement analysis for the FSS of this survey unit.

The LTP, Section 5.6.4.4 and Table 5-15 specifies that for Class 2 structure survey units, systematic and judgmental surface scans will be performed on 10% to 100% of the surface area in the survey unit. For survey unit B2-010-101, 25% scan coverage was selected; this equates to 265 m2. Thirty (30) scan areas (one [1] scan area at each systematic measurement location and two [2] judgmental scan areas), covering 322.13 m2 of the survey unit (more than the required minimum), were established. Refer to Attachment 1 for figures and maps depicting the measurement and scan locations in survey unit B2-010-101.

For this Class 2 structure survey unit, the Investigation Levels for area scanning and direct measurement results are those levels specified in the LTP, Table 5-16, and reproduced below in Table 5-2.

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FSS RELEASE RECORD LACBWR CRIB HOUSE SURVEY UNIT B2-010-101 Table 5 Investigation Levels Direct Investigation Classification Scan Investigation Levels Levels

>Operational DCGL or >MDCscan if Class 2 MDCscan is greater than Operational >Operational DCGL DCGL Table 5-3 provides a synopsis of the survey design for survey unit B2-010-101.

Table 5 Synopsis of Survey Design Feature Design Criteria Basis Survey Unit Surface Area 1,060 m2 Building Dimensions

= 473 UBGR = 3,160 Number of Systematic 28 (14 interior and 14 exterior) LBGR = 1,580 Measurements (N) Type I & II error = 0.05

/ = 3 (adjusted)

MARSSIM Table 5.5 Adjusted Gross Operational DCGL/Action Level 3,160 dpm/100 cm2 DCGL (Equation 2)

Direct Investigation Level >Operational DCGL LTP, Table 5-16 Scan Investigation Level >Operational DCGL or >MDCscan LTP, Table 5-16 322.13 m2 (with 2 judgmental LTP, Table 5-15 Scan Areal Coverage scan areas) or ~30% Actual Scan Coverage Judgmental Measurements 2 Per Survey Design 2 replicate measurements selected QC LTP, Section 5.9 at random locations

6. SURVEY IMPLEMENTATION For survey unit B2-010-101, compliance with the unrestricted release criteria was demonstrated through a combination of surface scanning and surface static measurements with a Ludlum Model 44-116 beta/gamma detector.

An FSS Supervisor performed a visual inspection and walk-down of the survey unit during the Unconditional Release Survey (URS) that was performed prior to FSS. The purpose of the walk-down was to assess the physical condition of the survey unit, evaluate access points and travel paths, and identify potentially hazardous conditions. At the time of FSS, the 13

FSS RELEASE RECORD LACBWR CRIB HOUSE SURVEY UNIT B2-010-101 interior and exterior of the building was dry and reasonably free of debris. No conditions prohibited the proper collection of static and scan measurements.

FSS field activities were conducted under the FSS Sample Plan, which included DQOs, survey design, detailed FSS instructions, job safety analysis, and related procedures for reference. FSS field activities were projected to take four (4) working days to complete.

Daily briefings were conducted to discuss the expectations for job performance and to review safety aspects of the job. A Field Log was used to document field activities and other information pertaining to the performance of the FSS. FSS field activities commenced on April 18, 2019, and were concluded on April 19, 2019.

A total of thirty (30) different scan areas (twenty-eight [28] systematic and two [2]

judgmental), constituting an areal coverage of 322.13 m2, were scanned using a Ludlum 2350-1 paired with a Ludlum Model 44-116 detector (125 cm2 detector area). The background was established as the average of five (5) 1-minute static measurements, while maintaining the detector waist high. In survey unit B2-010-101, background ranged from 157 cpm up to 234 cpm.

All designated scan areas were scanned using a Ludlum 2350-1 paired with a Model 44-116 beta/gamma detector operated in the rate-meter mode and using audio response. The probe was positioned as close to the surface as possible and was moved at a scan speed of approximately one (1) detector width per second. Scan MDC was sufficient to detect residual radioactivity at the action level of 3,160 dpm/100cm2 (Adjusted Gross Operational DCGL). Complete scan results are provided in Attachment 2.

The twenty-eight (28) systematic static measurement locations were marked based on the dimensions provided on the survey map. Two (2) judgmental measurement locations were selected and marked as per the sample plan. Using the Ludlum 2350-1 paired with a Model 44-116 detector, a 1-minute static measurement was acquired at the location of highest scan indication within each systematic and judgmental scan area.

The implementation of survey specific QC measures included the collection of two (2) replicate static measurements (B2-010-101-FQWM-A01-BD and B2-010-101-FQCM-B05-BD) for QC analysis.

7. SURVEY RESULTS All areas identified in the FSS plan were scanned for elevated activity levels. Three (3) alarms were produced during the scanning of survey unit B2-010-101. Static measurements collected at the locations of scan alarms were below the action level. Table 7-1 provides an overview of the scan results. Complete scan results are provided in Attachment 2.

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FSS RELEASE RECORD LACBWR CRIB HOUSE SURVEY UNIT B2-010-101 Table 7 Synopsis of Scan Results Highest Action # of Scan Logged Investigation Level(1) Scan Area Reading Measurements Alarms (cpm) (cpm)

A1 241 514 0 0 A2 225 541 0 0 A3 449 514 0 0 A4 231 514 0 0 A5 290 541 0 0 A6 499 514 0 0 A7 521 514 1 0 A8 315 541 0 0 A9 288 541 0 0 A10 517 514 1 0 A11 488 514 0 0 A12 256 541 0 0 A13 322 541 0 0 A14 253 514 0 0 A15 J 247 514 0 0 A1 QC 322 489 0 0 B1 712 469 1 0 B2 453 469 0 0 B3 452 538 0 0 B4 418 469 0 0 B5 256 541 0 0 B6 420 469 0 0 B7 404 538 0 0 B8 428 538 0 0 B9 452 538 0 0 B10 405 469 0 0 B11 463 538 0 0 B12 407 469 0 0 B13 513 538 0 0 B14 429 469 0 0 B15 J 530 538 0 0 B5 QC 443 489 0 0 15

FSS RELEASE RECORD LACBWR CRIB HOUSE SURVEY UNIT B2-010-101 (1) Action Level for scanning was conservatively based on the average background plus 50% of the Operational DCGL converted to cpm using the detector efficiency.

Background radiation was subtracted from all measurements, then were converted from cpm to dpm/100 cm2 (net cpm divided by detector efficiency) for direct comparison to the Adjusted Gross DCGLs. Table 7-2 below presents the detector efficiencies used for conversions. A summary of the results for the twenty-eight (28) systematic static measurements, two (2) judgmental static measurements, and two (2) QC static measurements is provided in Table 7-3. The basic statistics for the systematic measurement population are summarized in Table 7-4.

Table 7 Detector Efficiencies44-116 Efficiency Detector # (c/d)

PR 318218 0.149 PR 357009 0.2104 PR 357439 0.2169 Table 7 Summary of Systematic, Judgmental, and QC Static Measurements Gross Activity Fraction of Measurement ID Adjusted Gross (dpm/100 cm2) OpDCGL B2-010-101-FSWM-B01-BD 1732 0.5479 B2-010-101-FSWM-B02-BD 1168 0.3695 B2-010-101-FSCM-B03-BD 0 0.0000 B2-010-101-FSWM-B04-BD 0 0.0000 B2-010-101-FSCM-B05-BD 0 0.0000 B2-010-101-FSWM-B06-BD 0 0.0000 B2-010-101-FSFM-B07-BD 0 0.0000 B2-010-101-FSCM-B08-BD 0 0.0000 B2-010-101-FSFM-B09-BD 566 0.1790 B2-010-101-FSWM-B10-BD 329 0.1041 B2-010-101-FSCM-B11-BD 0 0.0000 B2-010-101-FSWM-B12-BD 121 0.0382 B2-010-101-FSFM-B13-BD 124 0.0391 B2-010-101-FSWM-B14-BD 101 0.0319 B2-010-101-FSWM-A01-BD 23 0.0073 16

FSS RELEASE RECORD LACBWR CRIB HOUSE SURVEY UNIT B2-010-101 Gross Activity Fraction of Measurement ID Adjusted Gross (dpm/100 cm2) OpDCGL B2-010-101-FSWM-A02-BD 0 0.0000 B2-010-101-FSRC-A03-BD 1452 0.4596 B2-010-101-FSWM-A04-BD 0 0.0000 B2-010-101-FSWM-A05-BD 23 0.0073 B2-010-101-FSRC-A06-BD 1268 0.4012 B2-010-101-FSRC-A07-BD 1406 0.4450 B2-010-101-FSWM-A08-BD 0 0.0000 B2-010-101-FSWM-A09-BD 46 0.0146 B2-010-101-FSRC-A10-BD 1259 0.3983 B2-010-101-FSRC-A11-BD 1485 0.4698 B2-010-101-FSWM-A12-BD 28 0.0088 B2-010-101-FSWM-A13-BD 0 0.0000 B2-010-101-FSWM-A14-BD 111 0.0350 B2-010-101-FQCM-B05-BD 204 0.0647 B2-010-101-FQWM-A01-BD 304 0.0963 B2-010-101-FJFM-B15-BD 371 0.1173 B2-010-101-FJWM-A15-BD 0 0.0000 Table 7 Basic Statistical Properties of Systematic Measurement Population Adjusted Mean Mean Median Max Min Std. Dev. Gross Adjusted Dose BcDCGL Gross (mrem/

BcDCGL yr)

(dpm/100cm2) (dpm/100cm2) (dpm/100cm2) (dpm/100cm2) (dpm/100cm2) (dpm/100cm2)

Fraction 401 37 1732 0 603 19751 0.0203 0.5081 The mean activity from systematic static measurements was divided by the Adjusted Gross Base Case DCGL to derive a mean fraction. The mean fraction was then multiplied by twenty-five (25) mrem/yr to derive the dose attributed to the survey unit. For survey unit B2-010-101, the calculated dose from residual activity is 0.5081 mrem/yr.

8. QUALITY CONTROL The implementation of survey specific QC measures included the collection of two (2) replicate static measurements (B2-010-101-FQCM-B05-BD and B2-010-101-FQWM-A01-17

FSS RELEASE RECORD LACBWR CRIB HOUSE SURVEY UNIT B2-010-101 BD) for QC analysis. The acceptance criteria for replicate static measurements is if the replicate measurement activity is within 20% of the standard measurement activity. The QC replicate measurements did not fall within the 20% criteria, but both the standard and replicate measurements were well below the Adjusted Gross Operational DCGL as well as the static MDC. Therefore, no further action was deemed necessary.

9. INVESTIGATIONS AND RESULTS No investigations were performed during the performance or analyses of the survey.
10. REMEDIATION AND RESULTS No radiological remedial action as described by MARSSIM Section 5.4 was performed in this survey unit prior to or as a result of the FSS. Chapter 4 of the LTP determined that remediation beyond that required to meet the release criteria is unnecessary and that the remaining residual radioactivity in above grade buildings was ALARA.
11. CHANGES FROM THE FINAL STATUS SURVEY PLAN There were no addendums to the FSS plan.
12. DATA QUALITY ASSESSMENT (DQA)

The DQO sample design and data were reviewed in accordance with LC-FS-PR-008, Final Status Survey Data Assessment (Reference 11) for completeness and consistency.

Documentation was complete and legible. Scan surveys and the collection of static measurements were consistent with the DQOs and were sufficient to ensure that the survey unit was properly designated as Class 2. The survey design had adequate power as indicated by the Retrospective Power Curve (see Attachment 5).

The measurement results indicated that all measurements, with the exception of one (1),

were less than 50% of the Adjusted Gross Operational DCGL.

Although MARSSIM states that the Sign test need not be performed in the instance that no measurements exceed the DCGL, the test was conducted to demonstrate coherence to the statistical principles of the DQO process. The Sign test was performed on the data and compared to the original assumptions of the DQOs. The evaluation of the Sign test results clearly demonstrates that the survey unit passes the unrestricted release criteria, thus, the null hypothesis is rejected. The results of the Sign test are presented in Attachment 3.

The preliminary data review consisted of calculating basic statistical quantities (e.g., mean, median, standard deviation). The mean and median values of the data were well below the 18

FSS RELEASE RECORD LACBWR CRIB HOUSE SURVEY UNIT B2-010-101 Adjusted Gross Operational DCGL. Also, the retrospective power curve shows that a sufficient number of measurements were collected to achieve the desired power. Therefore, the survey unit meets the unrestricted release criteria with adequate power as required by the DQOs.

The survey unit data is presented graphically through a frequency plot and quantile plot. All graphical presentations are provided in Attachment 5.

13. ANOMALIES No anomalies were observed during the performance or analyses of the survey.
14. CONCLUSION Survey unit B2-010-101 has met the DQOs of the FSS plan. The ALARA criteria as specified in Chapter 4 of the LTP were achieved.

The sample data passed the Sign test. The null hypothesis was rejected. The Retrospective Power Curve showed that adequate power was achieved. The survey unit is properly classified as Class 2. Therefore, in accordance with the LTP, Section 5.11, the survey unit meets the release criteria.

The dose contribution from survey unit B2-010-101 is 0.5081 mrem/yr TEDE, based on the mean activity of measurements used for non-parametric statistical sampling.

Survey unit B2-010-101 is acceptable for unrestricted release.

15. REFERENCES
1. LC-FS-PR-009, Final Status Survey Data Reporting
2. La Crosse Boiling Water Reactor License Termination Plan
3. LC-FS-PR-015, Final Status Surveys for Structures
4. LC-FS-PR-002, Final Status Survey Package Development
5. NUREG-1575, Revision 1, Multi-Agency Radiation Survey and Site Investigation Manual (MARSSIM)
6. La Crosse Boiling Water Reactor Historical Site Assessment
7. RS-TD-313196-001, Radionuclides of Concern during LACBWR Decommissioning
8. NUREG-1757, Volume 2, Revision 1, Consolidated Decommissioning Guidance -

Characterization, Survey, and Determination of Radiological Criteria, Final Report

9. LC-FS-TSD-002, Operational Derived Concentration Guideline Levels for Final Status Survey
10. LC-QA-PN-001, Final Status Survey Quality Assurance Project Plan
11. LC-FS-PR-008, Final Status Survey Data Assessment 19

FSS RELEASE RECORD LACBWR CRIB HOUSE SURVEY UNIT B2-010-101

16. ATTACHMENTS Attachment 1 - Figures and Maps Attachment 2 - Scan Data Attachment 3 - Sign Test Attachment 4 - Quality Control Assessment Attachment 5 - Graphical Presentations Attachment 6 - Ludlum 2350-1 Download Reports 20

FSS RELEASE RECORD LACBWR CRIB HOUSE SURVEY UNIT B2-010-101 ATTACHMENT 1 FIGURES AND MAPS 21

FSS RELEASE RECORD LACBWR CRIB HOUSE SURVEY UNIT B2-010-101 Figure 16 Survey Unit B2-010-101 Systematic and Judgmental Measurement Locations Map (Exterior) 22

Figure 16 Survey Unit B2-010-101 Systematic and Judgmental Measurement Locations Map (Interior) 23

FSS RELEASE RECORD LACBWR CRIB HOUSE SURVEY UNIT B2-010-101 ATTACHMENT 2 SCAN DATA 24

FSS RELEASE RECORD LACBWR CRIB HOUSE SURVEY UNIT B2-010-101 Table 16 Survey Unit B2-010-101 Complete Scan Data Scan Avg Action Detector Detector M2350-1 Logged Scan Location Background Level(1)

Type ID ID Result Alarms (cpm) (cpm) (cpm)44-116 357439 325261 A1 241 172 514 0 44-116 357439 325261 A2 225 199 541 0 44-116 357439 325261 A3 449 172 514 0 44-116 357439 325261 A4 231 172 514 0 44-116 357439 325261 A5 290 199 541 0 44-116 357439 325261 A6 499 172 514 0 44-116 357439 325261 A7 521 172 514 1 44-116 357439 325261 A8 315 199 541 0 44-116 357439 325261 A9 288 199 541 0 44-116 357439 325261 A10 517 172 514 1 44-116 357439 325261 A11 488 172 514 0 44-116 357439 325261 A12 256 199 541 0 44-116 357439 325261 A13 322 199 541 0 44-116 357439 325261 A14 253 172 514 0 44-116 357439 325261 A15 J 247 172 514 0 44-116 357009 325246 A1 QC 322 157 489 0 44-116 318218 120636 B1 340 234 469 0 44-116 318218 120636 B1 712 234 469 1 44-116 318218 120636 B2 453 234 469 0 44-116 357009 325246 B3 452 206 538 0 44-116 318218 120636 B4 418 234 469 0 44-116 357439 325261 B5 256 199 541 0 44-116 318218 120636 B6 420 234 469 0 44-116 357009 325246 B7 404 206 538 0 44-116 357009 325246 B8 428 206 538 0 44-116 357009 325246 B9 452 206 538 0 44-116 318218 120636 B10 405 234 469 0 44-116 357009 325246 B11 463 206 538 0 44-116 318218 120636 B12 407 234 469 0 44-116 357009 325246 B13 513 206 538 0 44-116 318218 120636 B14 429 234 469 0 44-116 357009 325246 B15 J 530 206 538 0 44-116 357009 325246 B5 QC 443 157 489 0 (1) Action Level for scanning was conservatively based on the average background plus 50% of the Operational DCGL converted to cpm using the detector efficiency.

25

FSS RELEASE RECORD LACBWR CRIB HOUSE SURVEY UNIT B2-010-101 ATTACHMENT 3 SIGN TEST 26

FSS RELEASE RECORD LACBWR CRIB HOUSE SURVEY UNIT B2-010-101 Table 16 Survey Unit B2-010-101 Sign Test SOF

  1. 1-WS Sign (WS) 1 0.5479 0.45 +1 2 0.3695 0.63 +1 3 0.0000 1.00 +1 4 0.0000 1.00 +1 5 0.0000 1.00 +1 6 0.0000 1.00 +1 7 0.0000 1.00 +1 8 0.0000 1.00 +1 9 0.1790 0.82 +1 10 0.1041 0.90 +1 11 0.0000 1.00 +1 12 0.0382 0.96 +1 13 0.0391 0.96 +1 14 0.0319 0.97 +1 15 0.0073 0.99 +1 16 0.0000 1.00 +1 17 0.4596 0.54 +1 18 0.0000 1.00 +1 19 0.0073 0.99 +1 20 0.4012 0.60 +1 21 0.4450 0.56 +1 22 0.0000 1.00 +1 23 0.0146 0.99 +1 24 0.3983 0.60 +1 25 0.4698 0.53 +1 26 0.0088 0.99 +1 27 0.0000 1.00 +1 28 0.0350 0.96 +1 Number of positive differences (S+) 28 Critical Value 18 Survey Unit Meets the Acceptance Criteria 27

FSS RELEASE RECORD LACBWR CRIB HOUSE SURVEY UNIT B2-010-101 ATTACHMENT 4 QUALITY CONTROL ASSESSMENT 28

FSS RELEASE RECORD LACBWR CRIB HOUSE SURVEY UNIT B2-010-101 Table 16 Survey Unit B2-010-101 QC Assessment Activity Activity Within Standard -20% +20% Comparison (dpm/100cm2) (dpm/100cm2) 20%

B2-010-101-FSCM-B05-BD 0 0 0 B2-010-101-FQCM-B05-BD 204 N B2-010-101-FSWM-A01-BD 23 18 28 B2-010-101-FQWM-A01-BD 304 N 29

FSS RELEASE RECORD LACBWR CRIB HOUSE SURVEY UNIT B2-010-101 ATTACHMENT 5 GRAPHICAL PRESENTATIONS 30

FSS RELEASE RECORD LACBWR CRIB HOUSE SURVEY UNIT B2-010-101 Figure 16 Quantile Plot for Gross Activity 31

FSS RELEASE RECORD LACBWR CRIB HOUSE SURVEY UNIT B2-010-101 Figure 16 Histogram for Gross Activity 32

FSS RELEASE RECORD LACBWR CRIB HOUSE SURVEY UNIT B2-010-101 Figure 16 Retrospective Power Curve 33

FSS RELEASE RECORD LACBWR CRIB HOUSE SURVEY UNIT B2-010-101 ATTACHMENT 6 LUDLUM 2350-1 DOWNLOAD REPORTS

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