Text

Us Dept of Transportation - Nuclear Ship Savannah, Survey Unit Release Record Survey Unit STR-105-01 Reactor Compartment - Lower Level (5-23) Starboard-side Half
	ML25328A169
Person / Time
Site:	NS Savannah
Issue date:	11/20/2025
From:	Roberson D; US Dept of Transportation, Maritime Admin, Nuclear Ship Support Services
To:	; Office of Nuclear Reactor Regulation
References
	Download: ML25328A169 (0)
	v • d • e

U.S. Department of Transportation Maritime Administration Office of Ship Operations Nuclear Ship Savannah Survey Unit Release Record Survey Unit STR-105-01 Reactor Compartment - Lower Level (5' - 23') Starboard-side Half Approved:

Prepared by:

Nuclear Ship Support Services, LLC

SAVANNAH Technical Staff Survey Unit Release Record PREPARED BY/ DATE:

PEER REVIEW / DATE:

DECOMMISSIONING PROGRAM MANAGER REVIEW /DATE:

INDEPENDENT REVIEW /

DATE:

FSS MANAGER REVIEW/ DATE:

LICENSING and COMPLIANCE MANAGER REVIEW/ DATE:

SAFETY REVIEW COMMITTEE SUBMITTED/ APPROVED LICENSE TERMINATION PLAN MANAGER REVIEW/ DATE:

Survey Unit STR-105-0 I D. Roberson Douglas Roberson Digitally signed by D. Roberson Date: 2025.05.15 12:57:38 -05'00' Date Pete HO 11 en bee k Digitally signed by Pete Hollenbeck Date: 2025.05.15 14:31 :26 -04'00' Pete Hollenbeck, CHP Soeuth Caleb Soeun Soeuth C. Soeun James Reese, CHP, RRPT James Reese Date Digitally signed by Soeuth Caleb Soeun Date: 2025.05.19 10:16:46 -04'00' Date Digitally signed by James Reese, CHP, RRPT Date: 2025.05.20 06:39:34 07'00' Date Dan*1el R M"1ha1*1 k Digitally signed by Daniel R.Mihalik Date: 2025.05.21 07:31 :07 -04'00' Daniel Mihalik Date JO h n

~~~ally signed by: John Osborne DN: CN = John Osborne LCM email Osborne LCM

=jmosborne@nsss.llcC=AD Date: 2025.06.05 12:39:14 -05'00' John Osborne Date 5/26/2025 6/2/2025 Submitted Approved 9/2/2025 Eric Darois Date Page 2 of34 Reactor Compartment - Lower Level (5' - 23') Starboard-side Half

SAVANNAH Technical Staff Survey Unit Release Record TABLE OF CONTENTS

1.

EXECUTIVE

SUMMARY

.................................................................................................... 6

2.

SURVEY UNIT DESCRIPTION.......................................................................................... 6

3.

CLASSIFICATION BASIS................................................................................................... 7

4.

DATA QUALITY OBJECTIVES......................................................................................... 7

5.

SURVEY DESIGN............................................................................................................... 10

6.

SURVEY IMPLEMENTATION......................................................................................... 13

7.

SURVEY RESUL TS............................................................................................................. 14

8.

QUALITY CONTROL........................................................................................................ 16

9.

INVESTIGATIONS AND RESULTS................................................................................ 16

10. REMEDIATION AND RESULTS...................................................................................... 17

11. CHANGES FROM THE FINAL STATUS SURVEY PACKAGE................................. 17

12. DATA QUALITY ASSESSMENT (DQA)......................................................................... 17

13. ANOMALIES........................................................................................................................ 17

14. CONCLUSIONS................................................................................................................... 17

15. REFERENCES..................................................................................................................... 18

16. ATTACHMENTS................................................................................................................. 19 Survey Unit STR-105-01 Page 3 of34 Reactor Compartment - Lower Level (5' - 23') Starboard-side Half

SAVANNAH Technical Staff Survey Unit Release Record LIST OF TABLES Table 4 Radionuclide Fractions and Normalized Fractions............................................... 8 Table 4 15 mrem/y DCGLs for ROC and Ni-63.................................................................. 8 Table 4 Re-normalized Co-60 and Cs-137 Fractions.......................................................... 9 Table 4 Operational DCGLs................................................................................................ 10 Table 5 STR-105-01 Systematic Measurement Designations........................................... 11 Table 5 Scanning Coverage................................................................................................. 12 Table 5 Investigation Levels................................................................................................ 13 Table 7 Summary of Systematic, Judgmental, and QC Static Measurements................ 14 Table 7 Basic Statistical Properties of Static Measurement Population.......................... 15 Table 7 Scan Measurement Summary................................................................................ 16 Survey Unit STR-105-01 Page4 of34 Reactor Compartment - Lower Level (5' - 23') Starboard-side Half

SAVANNAH Technical Staff Survey Unit Release Record LIST OF ACRONYMS AND ABBREVIATIONS ALARA As Low As Reasonably Achievable DQA Data Quality Assessment DQO Data Quality Objective DCGL Derived Concentration Guideline Level FSS Final Status Survey HSA Historical Site Assessment IC Insignificant Dose Contributors LBGR Lower Bound of the Gray Region L TP License Termination Plan MARAD Maritime Administration MARSSIM Multi-Agency Radiation Survey and Site Investigation Manual MDC Minimum Detectable Concentration MDCR Minimal Detectable Count Rate NSS Nuclear Ship Savannah QC Quality Control RASS Remedial Action Support Survey ROC Radionuclides of Concern SOF Sum-of-Fraction TEDE Total Effective Dose Equivalent UBGR Upper Bound of the Gray Region USNRC United States Nuclear Regulatory Commission Survey Unit STR-105-01 Reactor Compartment - Lower Level (5' - 23') Starboard-side Half Page 5 of34

SAVANNAH Technical Staff Survey Unit Release Record

1.

EXECUTIVE

SUMMARY

This Survey Unit Release Record for survey unit STR-105-01, Reactor Compartment -

Lower Level (5' - 23') Starboard-side Half, has been generated in accordance with Maritime Administration (MARAD) procedure STS-005-035, Preparation of Survey Unit Release Records and FSS Final Reports [ 1] and satisfies the requirements of Section 5.10 of the Nuclear Ship SAVANNAH (NSS) License Termination Plan, STS-004-003 [2].

A Final Status Survey (FSS) survey package for this survey unit was developed in accordance with MARAD procedure STS-005-030, Preparation of Final Status Survey Packages [3], the NSS License Termination Plan (LTP), and with guidance from NUREG-1575, Revision 1, Multi-Agency Radiation Survey and Site Investigation Manual (MARSSIM) [4].

This survey unit has a MARS SIM classification of 1. A survey package was designed based upon the use of the Sign Test as the nonparametric statistical test for compliance. Both the Type I (a) and Type II (~) decision error rates were set at 0.05. As a systematic measurement population, fifteen (15) static beta measurements were acquired from the survey unit. In addition, two judgmental static beta measurements were acquired. Surface scanning was performed on 100% of the accessible total surface area in the survey unit.

The data assessment results for survey unit STR-105-01 show that the maximum gross activity concentration among systematic and judgmental measurements is equal to 1,149.58 dpm/100 cm2, which is 2.20% of the operational Derived Concentration Guideline Level (DCGLw) value of 52,300 dpm/100 cm2. Therefore, the null hypothesis of the Sign test is rejected, and survey unit STR-105-01 is acceptable for unrestricted release. The mean gross activity concentration among the systematic and judgmental measurements is equal to 576.78 dpm/100 cm2, which is 0.83% of the 15 rnrem/y gross activity DCGLw of 69,700 dpm/100 cm2. The mean gross activity concentration is equal to 0.12 rnrem/y for the survey unit.

2.

SURVEY UNIT DESCRIPTION STR-105-01 is an impacted Class 1 survey unit. The reactor compartment where the containment vessel is located extends from 5' Elevation (Tanktop) to above the A Deck level. The reactor compartment contains support systems for the reactor plant. STR-105-01 is the Port-side of the reactor compartment lower level, 5' - 23' elevation. Based upon Computer Aided Design drawings, the deck surface area is approximately 99.44 square meters (99.44 m2); the total surface area, including the bulkheads and overhead, is approximately 352.16 m2; this includes the surfaces above 2 meters. Refer to Attachment 1 of this report for figures and maps depicting survey unit STR-105-01.

Survey Unit STR-105-01 Page 6 of34 Reactor Compartment - Lower Level (5' - 23') Starboard-side Half

SAVANNAHTechnical Staff' Survey Unit Release Record

3.

CLASSIFICATION BASIS

l -*+ *- d

brl Based on the NSS Historical Site Assessment [HSA] [5], survey unit STR-105-01, identified as survey unit 109Al in the HSA, was identified as a Class 1 structure survey unit. The HSA states primary coolant leaks were experienced from time to time, as was typical of nuclear power plants of the era. In the spring of 197 6, the primary and secondary systems were drained, and the removed liquid was transported to the Chem-Nuclear disposal site in Barnwell, South Carolina, for processing and disposal. The three primary system demineralizers were removed from the reactor compartment and shipped to Chem-Nuclear for disposal. Based upon a review of the historical information, the results of the characterization survey data, the 2024 Remedial Action Support Survey (RASS) STR-105-RASS-01-Rev 0, and the completion of a final Survey Unit Classification Worksheet, the correct final classification of survey unit STR-105-01 met the requirements of Class 1.

4.

DATA QUALITY OBJECTIVES FSS planning and design relies on a properly executed Data Quality Objective (DQO) process to ensure, through compliance with explicitly defmed inputs and boundaries, that the primary objective of the survey is satisfied. The DQO process is described in the NSS LTP in accordance with MARSSIM. 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 package, 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 STR-105-01 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).

MARAD Contractor Report CR-139, Calculations to Support NSS Surface Contamination DCGLs [6] established the basis for an initial suite of potential Radionuclides of Concern (ROC) for decommissioning. Insignificant dose 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 [7]. In all analyses, Cs-13 7 and Co-60 contribute Survey Unit STR-105-01 Page 7 of34 Reactor Compartment - Lower Level (5' - 23') Starboard-side Half

SAVANNAH Technical Staff Survey Unit Release Record nearly 100% of the total dose. The remaining radionuclides were designated as IC. Because Ni-63 comprises approximately 90% of the total activity, it is accounted for as a surrogate to Co-60. Therefore, the final ROCs for final status surveys are Cs-137 and Co-60surrogate-L TP Chapter 6, Section 6.13 discusses the process used to derive the ROC for the decommissioning of the NSS, including the elimination of insignificant dose contributors from the initial suite. Table 4-1 presents the initial suite ofROC for the decommissioning of the NSS, and the normalized mixture fractions based on the radionuclide mixture.

Table 4-1-Radionuclide Fractions and Normalized Fractions Normalized Sum of Sum of Only Co, Ni Nuclide Fractions Fractions and Cs C-14 3.37E-02 5.61E-03 Co-60 9.78E-02 l.63E-02 1.63E-02 Ni-63 5.40E+00 9.00E-01 9.00E-01 Sr-90 9.22E-06 l.54E-06 Tc-99 l.27E-04 2.1 lE-05 Ag-108m

-8.30E-04 l.38E-04 Cs-137 4.57E-01 7.61E-02 7.61E-02 H-3 1.93E-03 3.21E-04 Fe-55 8.l0E-03 1.35E-03 Am-241 5.79E-07 9.66E-08 Pu-239/240 4.81E-07 8.0lE-08 Totals 6.00E+o0 l.00E+00 9.93E-01 Each radionuclide-specific DCGLw 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 15 mrem/yr to an Average Member of the Critical Group. Table 4-2 presents the 15 mrem/y DCGLw for Co-60, Ni-63 and Cs-137 from Chapter 6 of the L TP.

Table 4 15 mrem/y DCGLs for ROC and Ni-63 Radionuclide DCGLw (dpm/100cm2)

Co-60 2.37E+04 Ni-63 2.53E+08 Cs-137 l.20E+05 Nickel-63 is a Hard-to-Detect (HTD) radionuclide. To account for Ni-63, the Easy-To-Detect (ETD) radionuclide Co-60 will be used as a surrogate.

Survey Unit STR-105-01 Page 8 of34 Reactor Compartment - Lower Level (5' - 23') Starboard-side Half

SAVANNAH Technical Staff Survey Unit Release Record The surrogate DCGL is computed as:

DCGLsurrogate = DCGLETD X DCGLnrD

(/HTD:ETvxDCGLE'm)+DCGLnTD Where:

DCGLETD = the DCGL for the easy-to-detect radionuclide DCGLttm = the DCGL for the hard-to-detect radionuclide Equation 1 FHTo:ETD

= the activity ratio of the hard-to-detect radionuclide to the easy-to-detect radionuclide Using the data in Table 4-1, the Ni-63/Co-60 ratio equals 55.3. Solving Equation 1 using the DCGLs for Co-60 and Ni-63 in Table 4-2 and the Ni-63/Co-60 ratio of 55.3 is shown below.

2.53E+08 d m/

2 DCGLco-60 surrogate= 2.37E + 04 X (

)

= 2.36E+04 p 100 cm 55.3 x 2.37E+04 +2.53E+08 A gross activity DCGLw has been established, based on the representative radionuclide mix, as follows:

Where:

n DCGLn 1

Gross Activity DCGLw = ti ti tn DCGL1 + DCGLz +* **vcGLn

= fraction of the total activity contributed by radionuclide n

= the number of radionuclides

= DCGL for the Radionuclide of Concern (ROC)

Equation 2 Of the three radionuclides, only Co-60 and Cs-137 can be detected by gross activity measurements. The normalized fractions for both radionuclides in Table 4-1 must be re-normalized for use in Equation 2. Table 4-3 presents the re-normalized fractions for each radionuclide.

Table 4-3 -Re-normalized Co-60 and Cs-137 Fractions Normalized Only Co-60 Re-sum of and Cs-137 normalized Nuclide fractions Fractions Fractions C-14 5.61E-03 Co-60 l.63E-02 1.63E-02 1.76E-01 Ni-63 9.00E-01 Sr-90 1.54E-06 Tc-99 2.l lE-05 Ag-108m 1.38E-04 Cs-137 7.61E-02 7.61E-02 8.24E-01 Survey Unit STR-105-01 Page 9 of34 Reactor Compartment - Lower Level (5' - 23') Starboard-side Half

SAVANNAH Technical Staff Survey Unit Release Record Nuclide H-3 Fe-55 Am-241 Pu-239/240 Totals Normalized sum of fractions 3.21E-04 1.35E-03 9.66E-08 8.0lE-08 1.00E+00 Only Co-60 Re-and Cs-137 normalized Fractions Fractions 9.24E-02 1.00E+00 Solving Equation 2 using the re-normalized Co-60 and Cs-137 fractions and the Co-60 surrogate DCGL is shown below.

Gross Activity DCGLw = l.76E-l l 8_24E-l = 6.97E+04 dpm/100 cm2.

2.36£ +o4 + 1.20E +os The DCGLs are reduced to a fraction of the 15 mrem/yr dose limit. The reduced DCGLs, or operational DCGL is then used as the DCGL for the FSS design of the survey unit (investigations levels, etc.). The operational DCGLs are set at 75% of the 15 mrem/y DCGLw. The operational DCGLs are provided in Table 4-4.

Table 4 Operational DCGLs Radionuclide Operational DCGL (dpm/100cm2)

Co-60 1.77E+04 Cs-137 9.00E+04 Gross Activity 5.23E+04 Instrument DQOs included a verification of the ability of the survey instrument to detect the radiation( s) of interest relative to the operational DCGLw. 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 ensure the quality and prevent the loss of data. MARSSIM states that a Minimum Detectable Concentration (MDC) below 10%

of the DCGL is preferable and up to 50% is acceptable. Because the background is low on the NSS, the MDC for most static and scan measurements were less than 10% of the DCGL and in all cases the MDCs were less than 50% of the DCGL.

5.

SURVEY DESIGN The LTP specifies that the Sign Test will be used 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 MARAD procedure STS-005-031, Calculation Of The Number of Measurements For Final Status Surveys. [8] The relative shift (Ncr) for the survey unit data set is defined as shift(~), which is the Upper Boundary of the Gray Region Survey Unit STR-105-01 Page 10 of34 Reactor Compartment - Lower Level (5' - 23') Starboard-side Half

SAVANNAH Technical Staff Survey Unit Release Record (UBGR), or the operational DCGLw, minus the Lower Bound of the Gray Region {LBGR),

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

The optimal value for Mcr should range between one (1) and three (3). The largest value the Mcr can have is three (3). If the !1/cr exceeds three (3), then the value of two (2) will be used for Mcr.

Remediation and RASS surveys were performed between 04/08/2024 and 05/06/2024 with an additional follow up remediation survey performed on 08/22/2024 in response to suspected Alpha concerns. A total of thirty-five (35) static measurements and 35 smears were collected five of which were post remediation taken on 08/06/2024. On 08/22/2024 following an additional remediation, 10 additional smears were collected. Post remediation, highest alpha activity was 18.425 dpm/100 cm2. The maximum beta activity was 91.579 dpm/100 cm2. The average total surface activity concentration and standard deviation of all static the measurements were 1,470 and 1,380 dpm/100 cm2, respectively.

Because the activity concentration is low, the LBGR was set to half the operational DCGL.

The relative shift for survey unit STR-105-01, is based upon the RASS survey results and was calculated as follows:

52,300-26,150 Relative Shift=------= 18.95 1,380 Because the calculated relative shift was greater than three (3), the value of two (2) was used as the adjusted !1/cr. Both the Type I error, or a value, and the Type II error, or~ 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 fifteen (15). Fifteen (15) total systematic measurements were used in the survey design for survey unit STR-105-01.

The survey unit was designated Class 1; therefore, the 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 measurements to be collected for FSS of survey unit STR-105-01.

Table 5 STR-105-01 Systematic Measurement Designations Label LX(m)

LY(m)

Surface STR-105-01-01

-14.89

-1.68 Deck STR-105-01-02

-10.04

-1.68 Deck STR-105-01-03

-5.19

-1.68 Deck STR-105-01-04

-0.34

-1.68 Deck Survey Unit STR-105-01 Page 11 of34 Reactor Compartment - Lower Level (5' - 23') Starboard-side Half

SAVANNAHTechnical Staff Survey Unit Release Record Label STR-105-01-05 STR-105-01-06 STR-105-01-07 S TR-105-01-08 STR-105-01-09 STR-105-01-10 STR-105-01-11 STR-105-01-12 STR-105-01-13 STR-105-01-14 STR-105-01-15 LX(m)

-17.96

-13.11

-8.26

-3.41 0.01 0.40 2.46 7.31 1.02 0.28 1.09 LY(m)

Surface 1.00 CV Shell Overhead 1.00 CV Shell Overhead 1.00 CV Shell Overhead 1.00 CV Shell Overhead 3.36 Bulkhead 2 3.36 Bulkhead 4 3.36 Bulkhead 6 3.36 Bulkhead 6 3.36 Bulkhead 7 3.36 Bulkhead 11 6.33 Bulkhead 7 The implementation of quality control (QC) measures is referenced in LTP Chapter 5, Section 5.11. A randomly chosen replicate measurement was specified in the survey package. This measurement was to be collected by either a different technician or by a different instrument. Location STR-105-01-10 was chosen for the replicate measurement.

In addition, the survey package also specified to perform QC operability checks of field instruments both prior to and after collection of the measurements.

The survey package also specified collection of two judgmental measurements to augment the systematic measurements. The locations of these two measurements were to be determined by the technicians and/or the field supervisor. Those two judgmental measurements are identified as STR-105-01-16-J and STR-105-01-17-J. Those locations would be documented on the field forms.

For this Class 1 structure survey unit, the "Scanning Coverage" are those levels specified in L TP Chapter 5, Table 5-3, and are reproduced below in Table 5-2.

Table 5 Scanning Coverage Classification Required Scanning Coverage Fraction Class 1 100%

For survey unit STR-105-01, fifteen scan areas were established SA-01 through SA-15.

The survey package stated to scan 100% of the accessible area in each scan area. Refer to for figures and maps depicting the measurement and scan locations in survey unit STR-105-01.

For this Class 1 structure survey unit, the "Investigation Levels" for direct and scanning measurement results are those levels specified in LTP Chapter 5, Table 5-2, and are reproduced below in Table 5-3.

Survey Unit STR-105-01 Page 12 of34 Reactor Compartment - Lower Level (5' - 23') Starboard-side Half

SAVANNAH Technical Staff Survey Unit Release Record Survey Unit Classification Class 1 Table 5-3 -Investigation Levels Fixed Measurements Scan Measurements

> Operational DCGLw and an outlier*

> Operational DCGLw These investigation levels were specified in the survey package.

An additional action level was specified in the survey package. If the technician observed a count rate of 2,500 cpm when scanning, approximately one-half of the investigation level, they were to stop scanning, backup and rescan the elevated location again to see if the count rate was observed again. If observed again, an additional static measurement would be collected. If not, they would continue scanning.

6.

SURVEY IMPLEMENTATION For survey unit STR-105-01, compliance with the unrestricted release criteria was demonstrated through a combination of surface scanning and surface static measurements with a Ludlum Model 43-93 ZnS detector connected to a Ludlum Model 3002 meter and a Ludlum Model 43-37 gas proportional detector connected to a Ludlum Model 3002 meter both operating in the beta mode.

Prior to performing the survey, a walkdown of the survey unit was performed per MARAD procedure STS-005-032, Survey Unit Turnover and Control. [9] No conditions prohibited the proper collection of static and scan measurements.

FSS field activities were conducted under the approved FSS Package Number NSS-FSSP-STR-105-01-00-00, which included DQOs, survey design, detailed FSS instructions, survey maps and survey forms. FSS field activities were projected to take approximately six ( 6) working days to complete. A daily briefing was conducted to discuss the expectations for job performance and to review safety aspects of the job. An FSS package "Field Log" was used to document field activities and other information pertaining to the performance of the FSS. The FSS field activities took eight days to complete and was performed on December 2, 2024, through December 5, 2024, December 10, 2024, December 16, 2024, December 18, 2024, and December 30, 2024.

Ambient background count rates were collected by taking a I-minute static measurement, while maintaining the detector waist high. This value was used to calculate the MDC for scanning and static measurements.

The fifteen (15) 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. A 1-minute static measurement was acquired at each location with the detector in contact with the surface.

Survey Unit STR-105-01 Page 13 of34 Reactor Compartment - Lower Level (5' - 23') Starboard-side Half

SAVANNAH Technical Staff Survey Unit Release Record The fifteen scan areas, SA-01 through SA-15, were scanned, resulting in 100% of the total surface area being scanned. The total scan area meets the scan coverage requirements for a Class 1 area as shown in LTP Table 5-3 and reproduced in Table 5-2 of this release record. Scanning was performed with the detector held approximately 0.75 inches from the surface while moving at a speed of one detector width per second.

The implementation of survey specific QC measures included the collection of one replicate static measurement. The random location of the replicate measurement was STR-105-01-10 and identified as STR-105-01-10-D. That measurement was collected with a different instrument but the same make and model used for all the other measurements.

The instruments used for this survey were satisfactorily checked prior to and after performing the survey.

7.

SURVEY RESULTS The efficiencies used to convert count rates to activity are weighted efficiencies in which the Tc-99 (Co-60 surrogate) and Cs-137 efficiencies are weighted by the fraction Co-60 and Cs-137 comprise the NSS fmgerprint. This is documented in CR-164 [10]. For example, if the 41t contact Tc-99 efficiency is 0.1002 c/d and the 41t Cs-137 contact efficiency is 0.1868 c/d, the weighted contact efficiency is shown below.

Weighted efficiency (c/d) = (0.1002)(0.176) + (0.1868)(0.824) = 0.1716 c/d Copies of the instrument calibration records are presented in Attachment 2.

The ambient background count rate from a I-minute count was 97 cpm and was rounded up to 100 cpm. The un-painted flat surface contact detector weighted efficiency is equal to 0.1775 c/d. Using LTP Equation 5-6, which was derived from NUREG-1507, in which the count time and background count times are equal, results in an MDC for I-minute static measurements equal to 278.9 dprn/100 cm2 with an un-painted flat surface density. The value for un-painted flat surface contact is less than 1 % of the operational and gross activity DCGLw. Table 7-1 presents the activity concentration for all static measurements.

Table 7 Summary of Systematic, Judgmental, and QC Static Measurements Activity Concentration Measurement ID (dpm/100 cm2)

STR-105-01-01 490.26 STR-105-01-02 540.98 STR-105-01-03 563.52 STR-105-01-04 693.13 STR-105-01-05 540.98 STR-105-01-06 529.71 STR-105-01-07 540.98 STR-105-01-08 473.36 Survey Unit STR-105-01 Page 14 of34 Reactor Compartment - Lower Level (5' - 23') Starboard-side Half

SAVANNAH Technical Staff Survey Unit Release Record Measurement ID STR-105-01-09 STR-105-01-10 STR-105-01-11 STR-105-01-12 STR-105-01-13 STR-105-01-14 STR-105-01-15 STR-105-01-16-J STR-105-01-17-J STR-105-01-10-D Activity Concentration

( dpm/100 cm2) 287.40 326.84 625.51 540.98 591.70 540.98 557.88 1149.58 811.47 561.58 The raw static data with detector efficiencies are presented in Attachment 3.

Table 7-2 presents the basic statistical properties of the static measurement population, without the duplicate measurement.

Table 7 Basic Statistical Properties of Static Measurement Population Parameter Value Units Minimum Measurement 287.40 dpm/100 cm2 Maximum Measurement 1149.58 dpm/100 cm2 Mean 576.78 dpm/100 cm2 Median 540.98 dpm/100 cm2 Standard Deviation 189.22 dpm/100 cm2 Coefficient of Variation 0.33 unitless Residual activity dose rate 0.12 mrem/y The mean activity from static measurements was divided by the gross activity DCGLw to derive a mean fraction. The mean fraction was then multiplied by 15 mrem/yr to derive the dose attributed to the survey unit. For survey unit STR-105-01, the calculated dose from residual activity is 0.12 mrem/yr.

Calculation of the scan MDC for the Ludlum 43-37 detector used the rounded count rate of 200 cpm, the detector un-painted flat surface weighted efficiency of 0.1297 c/d at a distance of 0.75 inches and using LTP Equation 5-8, which was derived from NUREG-1507. The elevated area was assumed to be a 100 cm2 circular source. The detector width is 6.25 inches, and the detector speed is 6.25 in/second. With these parameters, the resulting observation interval is 0.711 seconds. The resulting MDC for scanning is 334.7 dpm/100 cm2. This value is less than 1 % of the operational DCGLw and gross activity DCGLw.

The scan MDC for the Ludlum 43-93 detector used the highest rounded count rate of 125 cpm, a distance of 0.75 inches, with the most conservative un-painted flat surface scan detector weighted efficiency of 0.1114 c/d. The detector width is 3.6 inches, and the detector speed is 3.6 in/second. With these parameters, the resulting observation interval is 1.234 seconds. The resulting MDC for un-painted flat surfaces scanning is 1,365.6 Survey Unit STR-105-01 Page 15 of34 Reactor Compartment - Lower Level (5' - 23'} Starboard-side Half

SAVANNAH Technical Staff Survey Unit Release Record dpm/100 cm2. The value is 2.6% of the operational DCGLw and 2.0% of the gross activity DCGLw.

Table 7-3 presents activity concentrations for all scan measurements.

Table 7 Scan Measurement Summary Low to High Range Average Scan ID (dpm/100 cm2)

(dpm/100 cm2)

SA-01 386.40 - 14759.91 7573.16 SA-02 120.50 - 1185.13 652.82 SA-03 287.30 - 873.03 580.17 SA-04 140.97 - 1102.85 621.91 SA-05 136.42 - 1151.15 643.79 SA-06 197.52 - 951.70 574.61 SA-07 716.45 - 1771.01 1243.73 SA-08 676.20 - 1337.76 1006.98 SA-09 511.76 - 1328.78 920.27 SA-10 258.11 - 1207.05 732.58 SA-11 338.10 - 732.55 535.33 SA-12 507.15 - 885.50 696.33 SA-13 346.15 - 885.50 615.83 SA-14 83.19 - 1894.19 988.69 SA-15 483.80 - 1615.39 1049.60 The raw scan data with detector efficiencies are presented in Attachment 3.

8.

QUALITY CONTROL The implementation of survey specific QC measures included the collection of one replicate static measurement (STR-105-01-10-D) for analysis. The acceptance criteria for replicate static measurements is defined by NUREG-157 6, MARLAP volume 1, Appendix C, Section C.4.2.2 Duplicate Analyses [11]. That section states that when the average of the two measurements is less than the UBGR, the control limit for the absolute difference between the two values is 4.24µMR. The value for µMR is equal to the shift divided by 10.

The shift is equal to the operational DCGLw, minus one half the operational DCGLw, or 26,150 dpm/100 cm2. Therefore, the control limit is equal to 11,087.6 dpm/100 cm2, as shown below.

Control limit= 26,150/10*4.24 = 11,087.6 dpm/100 cm2.

The results of the evaluation of the quality control measurement shows agreement between the original and duplicate measurements. See Attachment 4 for the results.

9.

INVESTIGATIONS AND RESULTS No investigation levels were triggered, and no investigations were performed as the result of the analysis of the collected data.

Survey Unit STR-105-01 Page 16 of34 Reactor Compartment - Lower Level (5' - 23') Starboard-side Half

SAVANNAHTecbnical Staff Survey Unit Release Record

10.

REMEDIATION AND RESULTS No radiological remedial action was performed in this survey unit as a result of the FSS.

11.

CHANGES FROM THE FINAL STATUS SURVEY PACKAGE There were no addendums to the FSS package which was developed in accordance with STS-005-030, Preparation of Final Status Survey Packages [3].

12.

DATA QUALITY ASSESSMENT (DQA)

The DQO sample design and data were reviewed in accordance with MARAD procedure STS-005-033, Final Status Survey Data Assessment and Investigation [12] 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 1.

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 operational DCGLw. The survey unit data is presented graphically in a frequency plot and quantile plot presented in Attachment 6.

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 S~gn 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 5.

13.

ANOMALIES No anomalies were observed during the performance of the survey.

14.

CONCLUSIONS Survey unit STR-105-01 has met the DQOs of the FSS package. The survey unit is properly classified as Class 1.

The sample data passed the Sign Test. The null hypothesis was rejected. Therefore, the survey unit meets the release criteria.

The dose contribution from residual activity in survey unit STR-105-01 is 0.12 mrem/yr TEDE, based on the mean activity of measurements used for non-parametric statistical sampling.

Survey unit STR-105-01 is acceptable for unrestricted release.

Survey Unit STR-105-01 Page 17 of34 Reactor Compartment - Lower Level (5' - 23') Starboard-side Half

SAVANNAH Technical Staff Survey Unit Release Record

15.

REFERENCES

[1] "STS-005-035, Preparation of Survey Unit Release Records and FSS Final Reports".

[2] "STS-004-003, N.S. Savannah License Termination Plan".

[3] "STS-005-030, Preparation of Final Status Survey Packages".

[4] "NUREG-1575, Multi-Agency Radiation Survey and Site Investigation Manual (MARSSIM), Revision 1, August 2000".

[5] "CR-003, STS-105-01, Historical Site Assessment, 2008".

[6] "CR-139, TSD 21-089, Calculations to Support NSS Surface Contamination DCGLs, Rev 01, September 2022".

[7] "NUREG-1757, Vol 2, Rev 1, Characterization, Survey, and Determination of Radiological Criteria".

[8] "STS-005-031, Calculation of The Number of Measurements For Final Status Surveys".

[9] "STS-005-032, Survey Unit Turnover and Control".

[10] "CR-164, TSD 23-126, "Calculation of Weighted Efficiencies and MDCs of Ludlum Detectors for Final Status Surveys on the NS Savannah", Rev 01 ".

[11] "NUREG-1576, Multi-Agency Radiological Laboratory Analytical Protocols Manual, MARLAP, July 2004".

[12] "STS-005-033, Final Status Survey Data Assessment and Investigation".

Survey Unit STR-105-01 Page 18 of34 Reactor Compartment - Lower Level (5' - 23') Starboard-side Half

SAVANNAH Technical Staff Survey Unit Release Record

16.

ATTACHMENTS - Figures and Maps - Calibration Records - Static and Scan Data - Quality Control Assessment - Sign Test - Graphical Presentations Survey Unit STR-105-01 Reactor Compartment - Lower Level (5' - 23') Starboard-side Half

Page 19 of34

SA VANNA/I Technical Staff Survey Unit Release Record - Figures and Maps Location of the Reactor Compartment - Lower Level (5' - 23 ') Starboard-side Half Survey Unit STR-I 05-0 I Reactor Compartment - Lower Level (5' - 23') Starboard-side Half Page 20of34

SAVANNAH Technical Staff Survey Unit Release Record Reactor Compartment - Lower Level (5' - 23') Starboard-side Half Systematic and Judgmental Static Locations o I ST~l-16-t I,

1 I Lh_STR-I0S-01 -01 ~

TR-IDS-01-02 TR-10 04

-V STR-105-01-03 3

a.hhud5 srn 1=1 1~.___1__,

°"""

STR-105-01-E:J-J IOS-01-10 TR-105-01-09 LEGE D:

VSP Origin Point in Ship Coordinates:

Tanktop Frame 100 6'9" Starboard of Centerline 5'0" above baseline NOTES STR-105-01-05 -$-5TR-10S-01-06 #TR-105-01-07 4 TR-10S-0 1-0 CV s 'JSP~,mo* l t...

SU!'fJC SA PLE LOCATIONS CREATED IN VISUAL SA~ PLE PLAN BOW b U BER OF S,1PLES* 15 Survey Unit STR-105-01 Reactor Compartment - Lower Level (5' - 23') Starboard-side Half PLACEMENT.1ETHOO: SYSTEMATIC START LOC. RANDOM 0

1.5 S

t::E::C::::l:===:===::::lMeters Page 21 of34

SAVANNAH Technical Staff Survey Unit Release Record Reactor Compartment - Lower Level (5' - 23 ') Starboard-side Half Scan Areas SA 1' BOW D Survey Unit STR-105-01 Reactor Compartment - Lower Level (5' - 23') Starboard-side Half Page 22 of34

S4 VANNA // Technical Staff Survey Unit Release Record - Calibration Records l -- --

Calibration Certificate

ID Number: 25035110000

20240305

1 RSCS Customer: Matthew G Hunter Radiation Safety & Control Serv,ces Inc 93 Ledge Road Seabrook NH 03874 Instrument Ludlum Model 3002 Probe Model Ludlum 43-93 Precision Check s erial Number 25035110 Serial Number 421346 Test1 I

Test2 I

Tesl3 I

Mean I

Results 4.98 kcpm I

4.99 kcpm I

Accuracy Check Range Target Value A5Found As Left AUTO 500 Kcpm II 498 Kcpm II 498 Kcpm

AUTO SO Kcpm II 49 8 Kcpm II 49 8 Kcpm #

AUTO 5Kcpm::

4.98 Kcpm 11 4.98 Kcpm #

AUTO 05 Kcpm" 0 499 Kcpm II 0499 Kcpm*

Readings with

Indicate ranges y,1,ere As-Found readings are >20~ of Target va'ue Readings with ** Indicate As--len readings are > 10. of Target value Readings with fl Indicate ranges were ca'Ibrated using a pulser Probe Isotope 43-93 421346 Tc-99 43-93 421346 Cs-137(Beta) 43-93 42 t 346 Tc-99 43-93 421346 Cs*137(Beta) 43-93 42 1346 Cs-t37(Beta) 43.93 421346 Tc-99 43-93 421346 Cs-137(Beta) 43-93 421346 Tc-99 l'hyslcat Checks Light Check ol Sc1nrnauon Probes Pus Outer Physic.al Check Pass Audio Function Check Pass Ca*,brauon Date Set Pan Commentt:

Customer Equipment ID Efficiency 0.0299 CID (4 Pl) 0 0540 CID (4 Pl) 0.0199 CID (4 Pi) 0 0517 CID (4 Pl) 0.2075 CID (4 Pl) 0 1156 CID (4 Pl) 0.1 326 cro (4 PIJ 0.0721 CID (4 Pl)

NIST Source ID 127356 T c-99 127357 Cs-I37(Beta) 127356 Tc-99 127357 Cs-137(Beta) 127357 Cs-137(Beta) 127356 Tc-99 127357 Cs-137(Beta) 127356 Tc-99 Electronics Checks High Volta e Geometry Flat Surface Flat Surface Flat Surface Flat Surface Flat Surface Flat Surface Flat Surface Flat Surface As Found 677 Volts Pass Source ID Pulser 98756 Pulser 98756 Pulser 98756 Pulser 98756 Comment OnGrale On Grate 3/4" Above Grate 3/4" Above Grate On Contact On Contact 3 4" Above Source 3/4* Above Source As Left 715 Volts Calibrated By Nicole Wedlg OC Review By Matthe.,

Hunter Date. Mar 05 2024 Expires Mer 05. 2025 OC Date: Mar 05 2024 Barool&lrn.. P1u \\Ute 30 20 1n t)IJ In taeronce oond1 o,

sed on I resul tal ng "

In

,t ilfnCS v11h no r tlllon t,y IIMl uncenmnty Ol lho meosur('lll('nt Uooss olllen,,M stated.

t> c ibrOIIOn was pe!1olmed by RSCS ot g3 Ledge Rd t<ool< N1 I uttlZJ<lg folowtng NIST Tmceoble sources Pul,;,or 0~7 (Col 0.,.,, <kl 31 2024 I Worked on cal

'edig Thi> reported e of,,.; suremern Is Stiltl>d, lhf> storrtml t111<P1tnmty ol n,pa,;, lff'lll!'llt rm.hIfll" by 111" COVffillJ" roci,-, k sum that he c~

pf

> to f'IPfOJWnOtPfy ~-.

Unless o en,,s;,

ed JJons perfooned in contormance 10 the toao-,,ng documents ANSI N323Afl 2013, RSCS Ne.v llompshire R IOO ve Matenal License Nt.rnbel 381 R RSCS 11D11 seMCeS ore µenonned tn ecCOfdance w 1he RSCS Rao, f'IOlec1K>O Program Ma I and s

C

,.111 AN5l L ZS40-I -l!rJ4 R

nd rnec*

requu<,tnool, of 1s01EC 1702!> 20 t 7 whi<< d..*monsuo tochn1cal compole a 111 r,o111 or 11011

'107 t 101 mlorm 1,on on of t'lli!>l11 10 wt11<h !ht* acer 001,on ppl i pj Survey Unit STR-105-01 Page23 of34 Reactor Compartment - Lower Level (5' - 23') Starboard-side Half

S,tv ANNAJJ Technical Staff Survey Unit Release Record Calibration Certificate.10 Number: 25035113000. 20240131

O RSCS Customer: Matthe<<G Hunter Radiation Safety & Control Services Inc 93 Ledge Road Seabrook NH 03874 Instrument Ludlum Model 3002 Probe Model Ludlum 43.37 Serlal Number 25035113 Serlal Number 190949 Precision Check Test1 I

Test2 I

Test3 I

5.01 kcpm I

4.99 kcpm I

5.00 kcpm I

Accuracy Check Range Target Value As Found AUTO 500 Kcpm #

500 Kcpm #

AUTO 50 Kcpm #

49.9Kcpm it AUTO 5 Kcpm#

5.01 Kcpm it AUTO 0.5 Kcpm11 0.499 Kcpmr:

Readings with

indicate ranges v.!here As-Found readings are >20% of Target value Readings with*

indicate As-left readings are >1 0% of Target value.

Readings with i: Indicate ranges were calibrated using a pulser Probe Isotope Efficiency NIST Source ID 43-37 t 90949 Tc-99 0 0585 CID (4 Pl) 127356 Tc-99 Mean I

5.00 kcpm I

As Len 500 Kcpm #

49 9 Kcpm #

5.01 Kcpm #

0.499 Kcpm#

Oeometry Flat Surface 43.37 190949 Cs*137(Beta) 0 1703 CID (4 Pl) 127357 cs-137(Beta)

Flat Surface 43-37 190949 Tc-99 0 0276 C/D (4 Pl) 127356 Tc-99 Flat Surface 43-37 190949 Cs-137(Beta) 0.0387 CID (4 Pl) 127357 Cs-137(Beta)

Flat Surface Physical Checks Electronics Checks As Found Outer Physical Check* Pass HI h Volta e 900 Volts Tap Test. Pass Audio Function Check* Pass CallbraUon Date Set: Pass Comments. Calibrated With Ludlum 43*37 S/N 190949 using 20' C to C cable for wall and overhead set up Customer Equ pment ID Results Pass Source ID Pulser 98756 Pulser 98756 Pulser 98756 Pulser 98756 Comment 314" Above Flat Surface 3/4" Above Flat Surface 314" Above Grate 3/4" Above Grate As Left 1800 Volts Calibrated By Nicole Wedig QC Review By Matthew Hunter Date* Jan 31. 2024 Expires* Jan 31. 2025 QC Date Jan 31. 2024 Atmosphenc Cond,uons - Tampernture 70 0 r Hun*d1ty 24 0 "- Boromawc Pressure 30 12,n.hg In tolerance condl1J01,s 01 based on test 1estJls fo!llng 1V1th111 spec1fl8d ~mots with no reduCIJOO by U,e unc0110,nty of the meosuremenl Th,~ cnl1bmuon wo~ pM°O<IMd by RSCS u ng fOllo\\,ing NIST Tmc~nhlP source<;

Pulse, 98756 - (Cal Due Oct 31 2024)

Wo, ed on cat,bmuon Nicole Wed1q Th,epootr,d ~pand,.i unc rto,nty ol n~

11&1110111 IS too s 111 s111nda1d unc r m11ty of n

¥,u1en>AAI mu*t~*ll<>d y the cov th coverage probob<I ty correspon<ls to oppro,omot*ly 95'->

Unless Olhefl,ise stated cohbmhons per1ooned,n conformance to tru! IOlkllMng documents ANSI N323AB-201 3 RSCS New Hompslvre Rad,oocuve Maten al IJcenw Numbef 381 R R cohbrolJO!I se<VK&S ore per1om18d 1n occo,dance w,th the RSCS Rod1ouon ProlecllOn Program M nua! and an<l,lrd OpQI ting Pr u, s C hb101100 Lobo, tory IS Ope< tod,n OCCO<dJn

\\\\1Ul AN ~NCSL 2540-1-l(i<J4 RSCS Inc hos been assessed by ANAB nd meets the reqlllfements of 1SO%C 17025 2017 while demonstraung t<Khnorol competence 111 the field ol cahbm on Refer 1n the Scope of Accred1tll1JOO AC-2079 for 1nlormouon on lhe types of cat,brahons 1n.,.h,ch this ocaedltlluon opphes This cahbrouon cerur,c te shoJI not be reproduced except III full without the e,press wn en consent of RSCS Inc I I Survey Unit STR-105-0 I Page 24 of34 Reactor Compartment - Lower Level (5' - 23') Starboard-side Half

S.1YANNA11 Technical Staff Survey Unit Release Record Calibration Certificate

ID Number: 25035118000

20240&06

0 RSCS customer:

Rad1at1on Safety & Control Servtces, Inc 93 Ledge Road Seabrook NH 03874 Instrument Ludlum Model 3002 Probe Model Ludlum 43-37 Precision Check Serial Number 250351 18 Serlal Number 281043 Test1 Test2 Tes13 Mean Results 4.!19 kcpm 5.01 kcpm 5.00 kcpm 5.00 kcpm Accuracy Check Range Target Value As Found As Left AUTO 500 Kcpm #

500 Kcpm #

AUTO 50 Kcpm #

49.9 Kcpm #

AUTO 5 Kcpm #

4.99 Kcpm #

AUTO 0.5 Kcpm It 0.501 Kcpm #

500 Kcpm It 49 9 Kcpm#

4.99 Kcpm It 0.501 Kcpm 11 Readings With

Indicate ranges where As-Found readings are >20% of Target value Readings with ** indicate As-left readings are >10% of Target value.

Readings with # Indicate ranges were calibrated using a pulser Probe lsoto Efficlenc NIST Source ID 43.37 281043 Tc-99 0.1071 CID (4 Pi) 127356 Tc-99 43-37 281043 C*-137(8eta) 0.1345 CID (4 Pl) 127357 Cs-137(Beta) 43.37 281043 Tc-99 0.0073 CID (4 Pi) 127356 Tc-99 43.37 281043 Cs-137(Beta) 0 0121 CID (4 Pl) 127357 Cs-1 37 Beta) 43.37 281043 Tc-99 0 1544 CID (4 Pi) 127356 Tc-99 43-37 281043 Cs-137(Beta) 0.1751 CID (4 Pi) 127357 Cs-137(Beta) 43-37 281043 Tc-99 0 011 3 CID (4 Pl) 127356 Tc-99 43-37 281043 Cs-1 37(Beta) 0 0136 CID (4 Pl) 127357 Cs-1 37(Beta)

Physical Checks Electronics Checks Outer Physical Check Pass High Voltage Tap Test Pass Audio Function Chee : Pass Cord check: Pass Calibration Date Set Pass Comments Efficiencies performed using 1.5" fiberglass grate as requested Customer Equ pment ID Oeomet Flat Surface Flat Surface Flat Surface Flat Surface Flat Surface Flat Surface Flat Surface Flat Surface As Found 1751 Volts Pass Source ID Pulser 98756 Pulsar 98756 Pulser 98756 Pulser 98756 Comment 3/4" Above Source 3/4" Above Source 314" Above Grate 314 Above Grate On Source On Source On Grate On Grate As Left 1800 Volts Calibrated By Nicole Wedlg OC Review By Matthew Hunler Date Jun 06, 2024 Expires Jun 06, 2025 QC Date Jun 06, 2024 Atn rc,mob 1 20 2 111llg In toloron<:e c la" ng w, 1n spec, "1d hrMs with no reoJcoon by lh unc no1nty ol mell"Urement T results COi :1 r :id hut 1n Uni s 0lh8MM by RS s 01 QJ I e<lg Rd <;,,nbrool-NH uU171ng dl ~.n,\\In<) NIST Tr~ ertble ""'"'"'

Pulser 96756 (C Due Oct 31, 2024)

Wo1 I (lfl hi~ lli<Ml 1r1,l, W1 1 g rhe reported expanded unceno1111y ol measurement is stated os the standard uncertllnty ol meosuramenl mu1, 10d by Ille cov ro e tacta k such Ihm the coverage probab1hty corresponds to opprox1ma:ety 95%

Uni,s 01hotw1 st.1ted, c nt po1formod 1n conlunn:,nc I fol -.ng unnnt AN'>l N373Afl ;,o 13 RSCS N v Homp</lor Rod i,

Ma\\enol l.Jcense umber 381 R RSC:. cohbrooon servtces ore perlormed m occordonce wrth the RSCS Rad10uon Protecbon Program Manunl ond landard ()per ling Proced hbr 1100 Lot>Or lory r Ol'(>r;ll In rco, 'VlC

,111 AN I N I ZM0 I 1'"'"1 Survey Unit STR-105-01 Page 25 of34 Reactor Compartment - Lower Level (5' - 23') Starboard-side Half

S,i v ANNAi, Technical Staff Survey Unit Release Record e

Calibration Certificate

ID Number: 25035147000

20240708

O RSCS Customer: Scott Ginter Radiation Safety & Control Services. Inc 93 Ledge Road Seabrook NH 03874 Instrument Ludlum Model 3002 Probe Model Ludlum 43-93 Serial Number 25035147 Serial Number 421411 Precision Check Test1 I

Test2 I

Test3 I

Mean I

Results 5.00 kcpm I

5.00 kcpm I

Pass Accuracy Check Range Target Value As Found As Left Source ID AUTO 500 Kcpm #

500 Kcpm i:

500 Kcpm #

Pulser 66151 AUTO 50 Kcpm #

50 Kcpm#

AUTO 5 Kcpm#

5 Kcpm#

AUTO 0.5 Kcpm 11 0.5 Kcpm::

Readings with

Indicate ranges where As-Found readings are >20% of Target value Readings with ** indicate As-left readings are >1 0% of Target value.

Readings with # Indicate ranges were calibrated using a pulser Probe Isotope 43-93 4214 11 Cs-137(Beta) 43-93 4214 11 Tc-99 43-93 4214 11 Cs-137(Beta) 43-93 4214 11 Tc-99 43-93 4214 11 Cs-137(Be1a) 43-93 421411 Tc-99 43-93 4214 11 Cs-137(Beta) 43.93 4214 11 Tc-99 Physical Checks Light Check of Scintilat,on Probes. Pass Outer Physical Check* Pass Tap Test Pass Audio Function Check Pass Cord check: Pass Efficiency 0.1940 CID (4 Pi) 0.1231 C/D (4 Pl) 0.1 435 CID (4 Pl) 0.0766 CJD (4 Pi) 0.0197 C/D (4 Pl) 0.0097 CJD (4 Pl) 0.0170 C/D (4 Pl) 0.0064 CID (4 Pl)

Comments* Efficiencies Using 1 112* Fiberglass Grate Provided.

Customl!r Equipment ID NIST Source ID 127357 Cs-137(Beta) 127356 Tc-99 127357 C~137(Beta) 127356 Tc-99 127357 Cs-137(Beta) 127356 Tc-99 127357 Cs-137(Beta) 127356 Tc-99 Electronics Checks High Vottage Calibrated By Jarod Fagan OC Review By Matthew Hunter AtmosphPr,c l.ond1lloffi t emperatu1e 7 t 6 ~ I lumtd4y 4b O Borometnc Pressure 29 86 II\\ hg 50 Kcpm #

Pulser 6615 1 5 Kcpm#

Pulser 66151 0.5Kcpm11 Pulser 66151 Geometrv Comment Flat Surface On Source Flat Surface On Source Flat Surface 314** Above Source Flat Surface 3/4" Above Source Flat Surface On Grate Flat Surface On Grate Flat Surface 314" Above Grate Flat Surface 3/4' Above Grate As Found As Left 682 Volts 682 Volts Date Jul 08. 2024 Expires: Jul 08, 2025 OC Date: Jul 08. 2024 In lof rnnco cond1ll0ns nr

<cd on I I r()';lj I llng 11h,n <J>PClfiod knllls \\\\11h no reductJOO by ti mcM.1inty t lho moasur('fll nl Tho r~,

comaIned herein relate only to the ~em Cllltbrated I.Jnless othem,se stmed this cahbmuon was performed by R CS at !*3 Ledge Rd -brook NH <nj1ZJng tile following NIST Traceoble sources

Pulse, 151 - (

Due All* 05 2025)

Workro Oil Clll1brn11on Jarod F

"' N cole Wod,g The reported expanded uncerumty of measurement rs staled s the slllndard uncenrunty or measurement mull,pbed by the coverage foct<x k such that the cover e probaMiy corresponds to aprroxmatety 95*

Unless otherwise stated, cahbrauons pertormed 111 conrormonce to the lollowing documents ANSI N323AB-20I3 RSCS ew I lompsh1re Rodl08 e

Moleflol License Number 381 R RSCS col*brooon seMces ore penorrned,n oct01donce wiu, U1e RSCS Rad101,on ProtecllOn Progrom Manual ond Stonda1d OpemOng Procedures Col1brn11011 Loboratory,s operated in accordance Mth ANS I SL Z540- 1-I994

~

&CI

.......... t,,c t) Leoi,t f\\o.,.-t..

Pr! 0lli'4 t

l.,~....f.l3t Ii

,.,., 7

~

I 1 f i Survey Unit STR-105-0 I Page26of34 Reactor Compartment - Lower Level (5' - 23') Starboard-side Half

S1vANNA11 Technical Staff Survey Unit Release Record Calibration C*rtlflcate

ID Number: 25017648000. 2024070!1. O RSCS Customer: Scotl Gint Radiation Sar ty & Control Servtces, tnc 93 Ledg Road Instrument Ludlum Mod I 3002 Probe Mod*I Ludlum 43 93 Sert Number 25017648 Seabrook NH 03874 S rfal Number 379676 Precision Check Tesl1 I

Tesl2 I

Test3 I

Mean I

50.00 kcpm I

49.80 kcpm I

49.87 kcpm I

Accuracy Check Range Target Value As Found Aa Left AUTO 500Kcpm#

499Kcpm#

499 Kcpm It AUTO 50Kcpmll 50 Kcpm#

50Kcpmll AUTO 5Kcpm#

4.99Kcpmll 4.99 Kcpm ti AUTO 0 5 Kcorn #

O.S05Kcpm#

0.505Kcpm#

Reading with* indicate ranges whore As-Found readings are >20% of Target value.

Reading with ** Indicate A -left reading are >10% orra,get value Readings with# lnd,cat ranges were caHbreted us,ng a pul r

PmlM Isotope 43-93 379676 Cs-137(Bcta) 43.93 379676 Tc-99 43.93 379676 Cs-137(Bel.ll) 43-93 379676 Tc-99 43-93 379676 Cs-137(Bete) 43-93 379676 Tc-99 43.93 379676 Cs-137(Bet~)

43-93 379676 Tc-99 43-93 379676 Sr/Y-90 43-93 379676 Th-228 Physical Checks Light Check of Scinlil lion Prob a: Pau Outer Physical Chee

Pass Tap Test Pa&S Audio Funciion Check: Pass Cord check. Pa s Comments*

Customw Equipment ID.

Efficleney 0.1918 C/0 (4 Pl) 0.1103 C/0 (4 Pl) 0.1351 C/0 (4 Pi) 0.0733 C/0 (4 Pi) 0.0196 CID (4 Pl) 0.0093 C/0 (4 Pl) 0.0152 CID (4 Pl) 0.0063 CID (4 Pl) 0.2165 CID (4 Pl) 0.0962 CID (4 Pi)

NIST Source ID Geometry 127357 Cs-137(Beta)

AatSurface 127356 Tc-99 Flat Surface 127357 Cs-137(Beta)

Flat Surface 27356 Tc-99 Flat Surface 127357 Cs 137(Beta)

Flat Surf cc 127356 Tc-99 Flet Surlec 127357 Cs-137(Beta)

Fl I Surface 127356 Tc-99 Flat Surface T6-173 Sr/Y-90 1 c:m T&-691 Th-230 1 cm Eloetronlcs Checks As Found 1----------

H I h VOltage 640 Volts Results PaH Source ID Put er 98766 Pulser 98756 Pulser 98756 Pulsor 98766 Comment On Sourc On Source 3/4* N:iov &ource 3/4* Above Source On Grate On Grete 3/4* Above Grate 3/4

Abov Grat As left 765 Votta Celibrat d By Jarod Fag n QC Rev w By Matthew Hunter Dalo Jul 09, 2024 Exp

s. Jul 09, 2025 QC Date: Jul 09, 2024 Almo1pherlc Cond'ton*

Temperature 71.1 'F, Hurnlolty 42 O %, Barornetr>e Pr ue:29.90 wmg In lolen,nce c:ond era based on I ruu I r,g y,,

n speo d I m,to wi'h no r-.d1t by !he unc-.-\\alnty of m sur rNltll The,.

coouined herein,-11 ooly 10 tho '

cafibnl\\ld Unles othffi,,lse t!aled, th!* cal tnt*on w s performed by RSCS 81 93 L dge Rd Seabrook NH uti*zmg the lollowi'lQ NIST Trac.obi 10\\JfCeS PiAsor 98756 * (Cef Due: Oc:I 31 20241 Worl<ed on calibration Jarod Fagan The reporu>d e11p11nded un ty ol rnea1uramen1 Is stated uh ~rd uncartllnty ol measurement m~ ~pl by 1t,e covorage factor k ouch lhal the coverag probab ly coo-esponds lo pp!~ y 95%

Uni otherw,se slated ca~

Ions pcrlornod h conlormonce to I lolowng doeumaNt,4,NSI Nl23AB-2013, RSCS New H ml)fhl*e Rldooactiw 1/2 k ri Survey Unit STR-105-01 Page 27 of34 Reactor Compartment - Lower Level (5' - 23') Starboard-side Half

S1 VANN/II, Technical Staff Survey Unit Release Record Calibration CertHicate - ID Number: 25017651000. 20240305.1 RSCS Customer: Matthew G Hunter Rad1at,on Safety & Control Services Inc 93 ledge Road Seabrook NH 03874 tnstrum*nt Ludlum Model 3002 Probe Model Lud um 43-93 Serial Number 25017651 Serial Number 312635 Precision Check Test1 I

Test2 I

Test3 I

Mean l

5.00 kcpm I

5.01 kcpm I

5.00 kcpm I

Accuracy Check Range Taraet Value As Found As Left AUTO 500 Kcpm #

500 Kcpm #

AUTO 50 Kcpm#

49.9 Kcpm #

AUTO 5 Kcpm #

5 Kcpm #

AUTO 0 5 Kcpm #

0 5 Kcpm tt Readings v1ith

Indicate ranges where As-Found readings are >20% of Target value.

Readings with ** Indicate As-left readings are >10% orTarget value.

Readings with it lndlca e ranges were calibrated using a pulser Probe lsotOP*

43-93 312635 Tc-99 43-93 312635 Cs-137(Beta) 43-93 312635 Cs-137(Beta) 43-93 312635 Tc-99 43-93 312635 Cs-137(Bela) 43-93 312635 Tc-99 43-93 312635 Cs-137(BetaJ 43-93 312635 Tc-99 Physical Checks l ight Check of Sclntilabon Probes: Pass Outer Physical Chee. Pass Tap Test Pass Audio Function Check. Pass Comments:

Efflctencv 0.0249 C/0 (4 Pl) 0.0546 C/0 (4 Pl) 0.0471 C/0 (4 Pl) 0.0193 C/0 (4 Pl) 0.1693 C/0 (4 Pl) 0.0876 CJD (4 Pl) 0.1 237 C/0 (4 Pl) 0.0537 CID (4 Pl)

NIST Source ID 127356 Tc-99 127357 Cr137(Beta) 127357 Cr137(Beta) 127356 Tc-99 127357 Cs-137{Beta) 127356 Tc-99 127357 Cs-137(Beta) 127356 Tc-99 Electronics Checks High Voltage 5 Kcpm #

0 5 Kcpm #

Geometrv Flat Surface Fial Surface Flat Surface Flat Surface Flat Surface Flat Surface Flat Surface Flat Surface As Found 710 Volts Resu,ts Pass Source 10 Pulser 98756 Pulser 98756 Pulser 98756 Pulser 98756 Comment On Grate On Grate 3/4" Ab ova Grate 314" Above Grate On Contact On Contact 314* Above Source 3/4' Above Source As Left 775 Volts Customer Equipment ID Calibrated By Nicole Wedlg OC Revle,\\/ By Matthe"'

Hunter Date Mar 05. 2024 Expires Mar 05, 2025 QC Date Mar 05. 2024 Air pllCIK' Cood,1r011

Temp,, tu11* 71 t F Hu1111d11Y

, 0

6"11on>>U1C Pr 11 30 2!11n'hg In tolermce conditions are based on lest results !al 11Q \\\\1lhm spec1hed llm<ts wrth no reducuon by the uncena,nly ol O,e n remenl Unless olherwt<;e sta*

1h15 callbrauon.-as performed by RSC 01 93 Ledqe Rd Seabr 11 utrlwng lhe f ng 1ST Troe !Ible sources Pul 987 (C Due Oc131 20241

!COie Wedlg The re erto1nry of measure es the st ord unce 1nry ol meesuremen mu 1pl,ed by coverooe f Of k such lhot rp<;prll f lo Of11"0Xlr1 Uni s r1011oo<.1 111 Malet 10I

!,hrnhon

<;UJndo1d C, libml l'ollh AN I I Z54 ** CrlC RSC, In ets Ille requirements 1702~ 2017 "

1te demonsu cohhrauon R I"< to Scope

, -:?079 lor mfOrmatroo on lhe 1Vfl8S of bbr irons to which this b rl Survey Unit STR-105-01 Page 28 of34 Reactor Compartment - Lower Level (5' - 23') Starboard-side Half

SAVANNAH Technical Staff Survey Unit Release Record - Static Data Count Rate Total Weighted Eff Meter ID Measurement ID (cpm)

(c/d) 25017648 STR-105-01-01 87 0.1775 25017648 STR-105-01-02 96 0.1775 25017648 STR-105-01-03 100 0.1775 25017648 STR-105-01-04 123 0.1775 25017648 STR-105-01-05 96 0.1775 25017648 STR-105-01-06 94 0.1775 25017648 STR-105-01-07 96 0.1775 25017648 STR-105-01-08 84 0.1775 25017648 STR-105-01-09 51 0.1775 25017648 STR-105-01-10 58 0.1775 25017648 STR-105-01-11 111 0.1775 25017648 STR-105-01-12 96 0.1775 25017648 STR-105-01-13 105 0.1775 25017648 STR-105-01-14 96 0.1775 25017648 STR-105-01-15 99 0.1775 25017648 STR-105-01-16-J 204 0.1775 25017648 STR-105-01-17-J 144 0.1775 25017651 STR-105-01-10-D 87 0.1549 Note: Meter ID 25017648, and Meter ID 25017651 are connected to a Ludlum model 43-93 detector with an area of 100 cm2.

Survey Unit STR-105-01 Page 29 of34 Reactor Compartment - Lower Level (5' - 23') Starboard-side Half

SAVANNAH Technical Staff Survey Unit Release Record Meter ID 25017648 25035110 25035110 25017651 25035113 25017651 25035147 25017648 25035113 25017648 25035113 25017648 25017651 25017651 25017648 25017651 25017651 25017648 25017651 25017651 25017651 25017648 25035147 25017648 25017648 25017648 25035118 25035110 25035110 - Scan Data Min/Max Range Average Location (cpm)

(cpm)

SA-01 48/1,400 724.00 SA-01 55/190 122.50 SA-01 97/1,800 948.50 SA-02 28/132 80.00 SA-02 106/197 151.50 SA-03 32/87 59.50 SA-03 45/115 80.00 SA-04 63/137 100.00 SA-04 124/246 185.00 SA-05 63/143 103.00 SA-05 120/276 198.00 SA-06 40/99 69.50 SA-06 32/99 65.50 SA-06 22/106 64.00 SA-07 89/220 154.50 SA-07 87/158 122.50 SA-07 90/135 112.50 SA-08 84/152 118.00 SA-08 92/149 120.50 SA-08 85/130 107.50 SA-09 57/148 102.50 SA-10 61/89 75.00 SA-10 34/159 96.50 SA-11 42/91 66.50 SA-12 63/110 86.50 SA-13 43/110 76.50 SA-14 63/112 87.50 SA-14 61/231 146.00 SA-15 59/197 128.00 Total Weighted eff (c/d) 0.1242 0.1220 0.1220 0.1114 0.1506 0.1114 0.1317 0.1242 0.1506 0.1242 0.1506 0.1242 0.1114 0.1114 0.1242 0.1114 0.1114 0.1242 0.1114 0.1114 0.1114 0.1242 0.1317 0.1242 0.1242 0.1242 0.1297 0.1220 0.1220 Note: Meter ID 25035113, and Meter ID 25035118 is connected to a Ludlum model 43-37 detector with an area of 584 cm2. Meter ID 25035110, Meter ID 25035147, Meter ID 25017648 and Meter ID 25017651 is connected to a Ludlum model 43-93 detector with an area of 100 cm2.

Survey Unit STR-105-01 Page 30 of34 Reactor Compartment-Lower Level (5' - 23') Starboard-side Half

SAVANNAH Technical Staff Survey Unit Release Record - Quality Control Assessment Measurement Value (dpm/100 cm2)

Initial measurement 326.84 Replicate measurement 561.58 Average 444.21 Absolute Value of the difference 234.74 Condition Absolute value of the Control Limit

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

Average < 52,300 234.74 11087.6 Survey Unit STR-105-01 Reactor Compartment - Lower Level (5' - 23') Starboard-side Half Result Pass Page 31 of34

SAVANNAH Technical Staff Survey Unit Release Record - Sign Test Measurement Result DCGLw - Result ID

( dpm/100 cm2)

(dpm/100 cm2)

STR-105-01-01 490.26 69209.74 STR-105-01-02 540.98 69159.02 STR-105-01-03 563.52 69136.48 STR-105-01-04 693.13 69006.87 STR-105-01-05 540.98 69159.02 STR-105-01-06 529.71 69170.29 STR-105-01-07 540.98 69159.02 STR-105-01-08 473.36 69226.64 STR-105-01-09 287.40 69412.60 STR-105-01-10 326.84 69373.16 STR-105-01-11 625.51 69074.49 STR-105-01-12 540.98 69159.02 STR-105-01-13 591.70 69108.30 STR-105-01-14 540.98 69159.02 STR-105-01-15 557.88 69142.12 STR-105-01-16-J 1149.58 68550.42 STR-105-01-17-J 811.47 68888.53 Parameter Result Number of Measurements 17 NumberofS+

17 Critical Value 12 Meets I Doesn't Meet Acceptance Criteria Meets Survey Unit STR-105-01 Reactor Compartment - Lower Level (5' - 23') Starboard-side Half Sign

+1

+1 Page 32 of34

SAVANNAH Technical Staff Survey Unit Release Record - Graphical Presentations Quantile Plot of Gross Activity Concentration 1200 1100

,-.. 1000

"' 8 900

(.)

0 0

800 8

.g-700

(.)

600 t:l 0

u 500

(.)

400 300 200 0%

10%

20%

30%

40%

50%

60%

70%

80%

90%

100%

Note: Gap between 33% and 60% is due to 5 measurements with the same value. See Table 7-1.

Survey Unit STR-105-0 l Page 33 of34 Reactor Compartment - Lower Level (5' - 23') Starboard-side Half

SAVANNAH Technical Staff Survey Unit Release Record Histogram Survey Unit Number: STR-105-01

(.) e

i O"

Cl) 1-,

Ji.,

Reactor Compartment -

Survey Unit Name: Lower Level (5' - 23')

Starboard-side Half 10 9

8 7

6 5

4 3

2 0

395 503 611 718 826 934 Upper end value (dpm/100 cm2)

Survey Unit STR-105-01 Reactor Compartment - Lower Level (5' - 23') Starboard-side Half 1042 1150 Page 34 of34

ML25328A169

Text

SUMMARY

SUMMARY

Navigation menu

Search