ML19077A061

Final Status Survey (FSS) Final Report - Phase 2, Part 1, Unit 1 Tendon Tunnel Embedded Floor Drain Pipe Survey Unit 06211

ML19077A061
Person / Time
Site:	Zion  File:ZionSolutions icon.png
Issue date:	01/09/2019
From:	Graham J ZionSolutions
To:	Office of Nuclear Material Safety and Safeguards
References
ZS-2019-0017
Download: ML19077A061 (32)

Text

ZION STATION RESTORATION PROJECT FINAL STATUS SURVEY RELEASE RECORD UNIT 1 TENDON TUNNEL EMBEDDED FLOOR DRAIN PIPE SURVEY UNIT 06211

FSS RELEASE RECORD U1 TENDON TUNNEL FLOOR DRAIN PIPE SURVEY UNIT 06211 PREPARED BY / DATE: J. Graham 1/9/2019 Radiological Engineer REVIEWED BY / DATE: P. Giza 1/9/2019 Radiological Engineer APPROVED BY / DATE: D. Wojtkowiak 1/9/2019 C/LT Manager

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FSS RELEASE RECORD U1 TENDON TUNNEL FLOOR DRAIN PIPE SURVEY UNIT 06211 TABLE OF CONTENTS

1. EXECUTIVE

SUMMARY

....................................................................................................4

2. SURVEY UNIT DESCRIPTION ..........................................................................................4

3. CLASSIFICATION BASIS ...................................................................................................4

4. DATA QUALITY OBJECTIVES (DQO) ............................................................................5

5. SURVEY DESIGN .................................................................................................................7

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

7. SURVEY RESULTS ............................................................................................................14

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

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

10. REMEDIATION AND RESULTS......................................................................................16

11. CHANGES FROM THE SURVEY PLAN ........................................................................16

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

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

14. CONCLUSION .....................................................................................................................17

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

16. ATTACHMENTS .................................................................................................................18 ATTACHMENT 1 - FIGURE AND MAPS ...........................................................................19 ATTACHMENT 2 - SAMPLE DATA ...................................................................................21 ATTACHMENT 3 - SIGN TEST ...........................................................................................24 ATTACHMENT 4 - QC DATA .............................................................................................27 ATTACHMENT 5 - GRAPHICAL PRESENTATIONS .......................................................29 LIST OF TABLES Table 1 - Dose Significant Radionuclides and Mixture................................................................... 6 Table 2 - Base Case and Operational DCGLs ................................................................................. 7 Table 3 - Surrogate Ratios ............................................................................................................... 8 Table 4 - Surrogate Base Case and Operational DCGLs ................................................................. 9 Table 5 - Typical FSS Instrument Detection Sensitivities............................................................. 11 Table 6 - Synopsis of Survey Design ............................................................................................ 12 Table 7 - Survey Data Collected .................................................................................................... 14 Table 8 - Instrument and detector .................................................................................................. 14 Table 9 - Unit 1 Tendon Tunnel Floor Drains - Statistical Summary........................................... 16

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FSS RELEASE RECORD U1 TENDON TUNNEL FLOOR DRAIN PIPE SURVEY UNIT 06211

1. EXECUTIVE

SUMMARY

This Final Status Survey (FSS) Release Record for Survey Unit #S3-06211AF, Unit 1 Tendon Tunnel 547 ft. elevation Embedded Floor Drain Pipe, has been generated for the Zion Station Restoration Project (ZSRP). The release record was developed in accordance with ZionSolutions procedure ZS-LT-300-001-005, Final Status Survey Data Reporting (Reference 1) and satisfies the requirements of Section 5.11 of the Zion Station Restoration Project License Termination Plan (LTP) (Reference 2).

FSS Sample Plan S3-06211AF was developed in accordance with ZionSolutions procedure ZS-LT-300-001-001, Final Status Survey Package Development (Reference

3) the ZSRP LTP, and guidance from NUREG-1575, Revision 1, Multi-Agency Radiation Survey and Site Investigation Manual (MARSSIM) (Reference 4).

A FSS was conducted to demonstrate that the concentrations of residual radioactivity are equal to or below site-specific Derived Concentration Guideline Levels (DCGL) corresponding to the dose criterion in 10 CFR 20.1402. The Unit 1 Tendon Tunnel Floor Drain piping was classified as MARSSIM Class 3.

The Tendon Tunnel drain pipe was surveyed with a Ludlum 2350-1 Data Logger paired with a 44-159 gamma detector. The survey plan required measurements to be collected at 10 foot intervals to provide for 10% survey coverage for the Class 3 survey unit. The length of this piping system was 524.21 linear feet.

For the FSS of the Tendon Tunnel floor drain pipe, 58 readings were obtained. All of the readings were below a Sum-of-Fraction (SOF) of 0.5 when compared against the Operational DCGL for embedded pipe (OpDCGLEP), with a mean OpSOF reading of 0.0184. The mean SOF, when compared against the Base Case DCGL for embedded pipe (BcDCGLEP) was 0.0004, which results in the dose calculated for this survey unit of 0.0092 mrem/yr.

2. SURVEY UNIT DESCRIPTION The Unit 1 Tendon Tunnel drain piping consists of a 4-inch Internal Diameter (ID) pipe that is 524.11 feet in length. The floor of the tunnel is at 548 ft. elevation, with the drain piping embedded in the concrete approximately 7-inches deep.

3. CLASSIFICATION BASIS Survey Unit #S3-06211AF was classified in accordance with ZionSolutions procedure ZS-LT-300-001-002, Survey Unit Classification (Reference 5).

The Tendon Tunnels are part of the Turbine Building basement FSS unit. The Turbine Building was initially classified as a Class 2 structure by the Zion Station Historical Site

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FSS RELEASE RECORD U1 TENDON TUNNEL FLOOR DRAIN PIPE SURVEY UNIT 06211 Assessment (HSA) (Reference 6). LTP Section 5.5.2.1.2 changed the classification of the Turbine Building basement from Class 2 to Class 3. The LTP states The FSS units for the basements of the Turbine Building, the Crib House/Forebay, WWTF and the Circulating Water Discharge Tunnels are designated as Class 3 as defined in MARSSIM, section 2.2 in that the FSS units are expected to contain levels of residual activity at a small fraction of the DCGLs, based on site operating history and previous radiation surveys.

Although the Unit 1 Tendon Tunnels were inaccessible during site characterization in 2013, the results of environmental monitoring of radiological effluents indicate that the residual radioactivity in this FSS unit is minimal, supporting the Class 3 classification.

4. DATA QUALITY OBJECTIVES (DQO)

Final Status Survey planning and design hinges on coherence with the 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 is described in the ZSRP LTP in accordance with MARSSIM. The appropriate design for a given survey will be 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 #S3-06211AF 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).

LTP Chapter 6, section 6.5.2 discusses the process used to derive the Radionuclides of Concern (ROC) for the decommissioning of ZNPS, including the elimination of insignificant dose contributors (IC) from the initial suite. Based upon the analysis of the mixture, it was determined that Co-60, Ni-63, Sr-90, Cs-134 and Cs-137 accounted for 99.5% of all dose in the non-activated contaminated concrete mixes.

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FSS RELEASE RECORD U1 TENDON TUNNEL FLOOR DRAIN PIPE SURVEY UNIT 06211 The residual radioactivity in embedded piping located below the 588 foot grade that will remain and be subjected to FSS is discussed in LTP Chapter 2, section 2.3.3.7 and TSD 14-016, Description of Embedded Piping, Penetrations, and Buried Pipe to Remain in Zion End State (Reference 7). The DCGLs for embedded piping are listed in LTP Chapter 5, sections 5.2.7 and 5.2.8.

The survey design for this FSS was developed using the isotopic mixture for the Containment. During Data Assessment, it was determined that the isotopic mix incorporated into the survey design was incorrect. The correct mixture to use for this piping system is the Auxiliary Building isotopic mixture. The Auxiliary Building isotopic mixture was deemed appropriate because the Tendon Tunnel drains are hydraulically connected to the Turbine Building Steam Tunnel drains, and have no connection to systems in Containment. The data analysis performed for this Release Record was performed using the Auxiliary Building isotopic mix.

Table 1 presents the ROC for the decommissioning at ZNPS and the normalized mixture fractions based on the radionuclide mixture.

Table 1 - Dose Significant Radionuclides and Mixture Auxiliary Building Radionuclide  % of Total Activity (normalized)(1)

Co-60 0.92%

Ni-63 23.71%

Sr-90 0.05%

Cs-134 0.01%

Cs-137 75.32%

(1) Based on maximum percent of total activity from Table 20 of TSD 14-019, normalized to one for the dose significant radionuclides.

A FSS is conducted on the interior surfaces of embedded piping to demonstrate that the concentrations of residual activity are equal to or below DCGLs corresponding to the dose criterion in 10CFR20.1402 (DCGLEP). DCGLEP were calculated for each of the remaining embedded pipe systems. The DCGLEP values for the Tendon Tunnel Drain embedded pipe system from LTP Chapter 6, section 6.13 are referred to as Base Case DCGLs.

At ZNPS, compliance is demonstrated through the summation of dose from four distinct source terms for the end-state (basements, soils, buried pipe and groundwater). Each radionuclide-specific Base Case DCGL is equivalent to the level of residual radioactivity

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FSS RELEASE RECORD U1 TENDON TUNNEL FLOOR DRAIN PIPE SURVEY UNIT 06211 (above background levels) that could, when considered independently, result in a Total Effective Dose Equivalent (TEDE) of 25 mrem per year to an Average Member of the Critical Group (AMCG). To ensure that the summation of dose from each source term is 25 mrem/year 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/year 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 ZionSolutions TSD 17-004, Operational Derived Concentration Guideline Levels for Final Status Survey (Reference 8).

The Base Case and Operational DCGLs for the Tendon Tunnel Embedded Pipe are listed in Tables 5-11 and 5-12 of the LTP, and are reproduced in the Table 2.

Table 2 - Base Case and Operational DCGLs Base Case Operational Radionuclide Embedded Pipe DCGL Embedded Pipe DCGL 2

pCi/m pCi/m2 Co-60 1.06E+10 2.12E+08 Cs-134 2.04E+09 4.08E+07 Cs-137 2.67E+09 5.34E+07 Ni-63 2.72E+11 5.44E+09 Sr-90 9.70E+07 1.94E+06

5. SURVEY DESIGN The level of effort associated with planning a survey is based on the complexity of the survey and nature of the hazards. Guidance for preparing FSS plans is provided in procedure ZS-LT-300-001-001 Final Status Survey Package Development.

The Survey Design for this FSS listed the radionuclides for the Containment mixture as the ROC for Survey Unit #S3-06211AF. This was corrected during data analysis to the isotopic mixture for the Auxiliary Building. Co-60, Ni-63, Sr-90, Cs-134 and Cs-137 are the ROC in Survey Unit #S3-06211AF.

During FSS, concentrations for Hard-to-Detect (HTD) ROC Ni-63 and Sr-90 are inferred using a surrogate approach. Cs-137 is the principle surrogate radionuclide for Sr-90 and

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FSS RELEASE RECORD U1 TENDON TUNNEL FLOOR DRAIN PIPE SURVEY UNIT 06211 Co-60 is the principle surrogate radionuclide for Ni-63. The mean, maximum and 95%

Upper Confidence Level (UCL) of the surrogate ratios for concrete core samples taken in the Auxiliary Building basement were calculated in ZionSolutions TSD 14-019, Radionuclides of Concern for Soil and Basement Fill Model Source Terms (Reference

9) and are presented in Table 3. The maximum ratios will be used in the surrogate calculations during this FSS. The results of the surrogate calculations are listed in Table 4.

Table 3 - Surrogate Ratios Auxiliary Building Ratios Mean Max 95%UCL Ni-63/Co-60 44.143 180.450 154.632 Sr-90/Cs-137 0.001 0.002 0.002 The equation for calculating a surrogate DCGL is as follows:

Equation 1 1

=

1 2 3

+ + +

2 3 Using the Base Case and Operational DCGLs presented in Table 2 and the maximum ratios from Table 3, the following surrogate calculations were performed:

Equation 2 (Cs-137 Surrogate Base Case DCGL) 1 (137) =

1 0.002

+

2.6709(137) 9.7007(90)

4.0009 /2 Equation 3 (Cs-137 Surrogate Operational DCGL) 1 (137)

1 0.002

+

5.3407(137) 1.9406(90)

= 5.0607 /2

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FSS RELEASE RECORD U1 TENDON TUNNEL FLOOR DRAIN PIPE SURVEY UNIT 06211 Equation 4 (Co-60 Surrogate Base Case DCGL) 1 (60) = = 1.3209 /2 1 180.45

+

1.0610(060) 2.7211(63)

Equation 5 (Co-60 Surrogate Operational DCGL) 1 (60) = = 2.6407 /2 1 180.45

+

2.128(060) 5.449(63)

Table 4 - Surrogate Base Case and Operational DCGLs Base Case Operational Radionuclide Embedded Pipe DCGL Embedded Pipe DCGL 2

pCi/m pCi/m2 Co-60 1.32E+09 2.64E+07 Cs-134 2.04E+09 4.08E+07 Cs-137 2.53E+09 5.06E+07 The survey design calculated a gross gamma Operational DCGL using the Containment mixture surrogate ratios. This value was 8.68E+06 pCi/m2. The Action Level used for the FSS of this survey unit was 50% of that value which equates to 4.34E+06 pCi/m2.

The actual gross gamma Operational DCGL using the Auxiliary Building mixture is 5.01E+07 and 50% of that value equates to 2.50E+07, which is less conservative than the Action Level that was actually used.

The Unit 1 Tendon Tunnel Floor drain system piping is Class 3 embedded pipe. For the survey of pipe internal surfaces, areal coverage is achieved by the area of detection for each static measurement taken. Scanning, in the traditional context, is not applicable to the survey of pipe internal surfaces. For the survey of these pipes, the pipe detector was calibrated for the specific geometry of the 4-inch diameter pipes. For a 4-inch diameter pipe, each measurement has a calculated Field-of-View (FOV) of 1.05 ft2 (0.097 m2).

The Unit 1 Tendon Tunnel Floor drain system piping contains 524.21 linear feet of 4-inch diameter pipe, which equates to a surface area of 51 m2. Procedure ZS-LT-300-001-001, Final Status Survey Package Development states that for the FSS of a Class 3 survey unit, an areal scan coverage of at least 10% is required. The survey design stated that one measurement was to be collected every 10 linear feet of piping traversed for a total of 52 distinct measurements over the entire accessible pathway of the piping system. In

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FSS RELEASE RECORD U1 TENDON TUNNEL FLOOR DRAIN PIPE SURVEY UNIT 06211 additional, for quality control purposes, a minimum of 5% of the measurements collected were to be duplicated. This would require an additional 3 measurements to be collected throughout the length of the accessible surface of the piping system at locations selected at random.

Each static measurement represents the gamma activity in gross cpm for each specific measurement location. This gamma measurement value in cpm was then converted to dpm using an efficiency factor based on the calibration source. The total activity in dpm was adjusted for the assumed total effective surface area commensurate with the pipe/penetration diameter, resulting in measurement results in units of dpm per m2. Unit conversion was then used to convert dpm to units of pCi. This measurement result, in units of pCi/m2, then represented a commensurate and conservative gamma surface activity The total gamma surface activity for each FSS measurement was then converted to a gamma measurement result (in units of pCi/m2) for each gamma ROC based on the normalized gamma mixture from Table 1. Concentrations for HTD ROC were inferred using a surrogate approach as per LTP Chapter 5. Cs-137 is the principle surrogate radionuclide for H-3 and Sr-90. Co-60 is the principle surrogate radionuclide for Ni-63.

The maximum ratios from Table 3 were used in the surrogate calculations.

The unity rule is applied when there is more than one ROC. The measurement results for each singular ROC present in the mixture were compared against their respective DCGL to derive a dose fraction. The summation of the dose fractions for each ROC produces a SOF for the measurement. When compared against the Base Case DCGL, the term is defined as BcSOF. When compared against the Operational DCGL, the term is defined as OpSOF.

To demonstrate that each survey unit satisfies the Operational DCGL, the ROC concentration for each systematic measurement taken in the Unit 1 Tendon Tunnel Embedded Floor Drain Pipe was divided by its applicable Operational DCGL (OpDCGLEP for embedded pipe) to derive a OpSOF for the ROC. The OpSOF for each ROC was then summed to determine the total OpSOF for all ROC that represents the measurement and was used as the summed value (Ws) for performing the Sign Test.

If the OpSOF for a systematic or judgmental measurement exceeded 0.5 in a Class 3 survey unit, then an investigation would be initiated in accordance with LTP Chapter 5, section 5.6.4.6 (Table 5-25). In a Class 3 FSS unit, the result of the investigation could prompt the reclassification of the survey unit (or a portion of the survey unit).

Embedded pipe survey units have a relatively small surface area leading to Operational DCGLs that are higher than the wall/floor Operational DCGLs. The reason for this fact is that the total internal surface area of the embedded pipe survey unit in a given basement being much less than the total wall/floor surface area of the basement containing them.

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FSS RELEASE RECORD U1 TENDON TUNNEL FLOOR DRAIN PIPE SURVEY UNIT 06211 To eliminate the potential for activity levels in embedded pipe that could lead to releases greater than surrounding walls and floors, the following remediation and grouting action levels will be applied to measurements of surface activity in embedded pipe.

• If maximum activity exceeded the Base Case DCGLEP from Table 2 (SOF >1), then remediation was performed.

• If the maximum activity in an embedded pipe exceeded the surface Operational DCGLB from LTP Chapter 5, Table 5-4 (SOF>1) in the building that contains it, but is below the Base Case DCGLEP from Table 2, then the embedded pipe was grouted.

• If an embedded pipe was remediated and the maximum activity continued to exceed the surface Operational DCGLB from LTP Chapter 5, Table 5-4 (SOF>1), but is less than the Operational DCGLEP from Table 3, then the embedded pipe was grouted.

• If the maximum activity was below the surface Operational DCGLB from LTP Chapter 5, Table 5-4 (SOF>1), then grouting of the pipe was not required.

The instrumentation used for the FSS of the Unit 1 Tendon Tunnel Drain embedded pipe was the Ludlum Model 2350-1 and the Model 44-159 detector. The instrumentation sensitivities are provided in Chapter 5 of the LTP and are reproduced in Table 5.

Table 5 - Typical FSS Instrument Detection Sensitivities BKGD Typical Typical Count Scan MDC Instrument Static MDC Radiation count time BKGD Instrument Time (dpm/100

/Detector (dpm/100 cm2)

(min.) (cpm) Efficiencyab (min.) cm2)

Ludlum 2350-1/ Gamma 1 700 0.024 1 5,250 N/A 44-159

a. Typical calibration source used is Cs-137. The efficiency is determined by counting the source with the detector in a fixed position from the source (reproducible geometry). The t value is based on ISO-7503-1 and conditions noted for each detector.

b. The efficiency varies for the pipe detectors depending on the pipe diameter used. The efficiency used for the table is the average efficiency value for the pipe diameters. The detectors and diameters are: model 44-159: 2-4 in. dia.,

model 44-157: 4-8 in. dia., model 44-162: 8-12 in. diameter.

In compliance with ZS-LT-01, Quality Assurance Project Plan (QAPP) for Characterization and Final Status Survey (Reference 10), replicate measurements were to be performed on 5% of the static measurement locations.

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FSS RELEASE RECORD U1 TENDON TUNNEL FLOOR DRAIN PIPE SURVEY UNIT 06211 Table 6 - Synopsis of Survey Design FEATURE DESIGN CRITERIA BASIS 4

Survey Unit Area 549 ft2 (51 m2) 524.21 12 /

Number of Static 52 10% areal coverage, Class 3 Measurements Measurement As needed to obtain sufficient 10% areal coverage, Class 3 Spacing measurements for 10% areal coverage

• Co 2.12E+08 pCi/m2

• Cs-134 - 4.08E+07 pCi/m2 Operational DCGLs for Unit 1 and Unit 2 Tendon Tunnel DCGLs

• Cs-137 -5.34E+07 pCi/m2 Embedded Pipe,

• Ni-63 -5.44E+09 pCi/m2 (LTP Chapter 5, Table 5-12)

• Sr-90 -1.94E+06 pCi/m2 Gross Gamma DCGL adjusted for HTD HTD ROC Analysis LTP 5.7.1.9 based on the isotopic mixture Measurement

>0.5 Gross Gamma Operational DCGL (LTP Chapter 5, Table 5-25)

Investigation Level Scan Survey Area N/A LTP 5.7.1.9 Coverage replicate measurements will be QC performed on 5% of the static QAPP measurement locations

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FSS RELEASE RECORD U1 TENDON TUNNEL FLOOR DRAIN PIPE SURVEY UNIT 06211

6. SURVEY IMPLEMENTATION Survey instructions for this FSS were incorporated into and performed in accordance with FSS Sample Plan #S3-06211AF, which was developed in accordance with ZionSolutions procedure ZS-LT-300-001-001. The FSS unit was inspected and controlled in accordance with ZionSolutions procedure ZS-LT-300-001-003, Isolation and Control for Final Status Survey (Reference 11).

The approach used for the radiological survey of the interior surfaces of the Tendon Tunnel floor drain piping involved the insertion of a 1 x 1 CsI detector that was attached to the See Snake camera system and transported through the pipe to the maximum deployment length, or to a location of drain drop. A simple push-pull methodology was used, whereby the position of the detector in the piping system could be easily determined in a reproducible manner. Footage was tabulated on the See Snake, then measurements were obtained at 10 foot intervals while backing out of the pipe section.

A background value was also determined for the detector/instrument combination to be used prior to deployment. The background value was obtained at the location where the pre-use response check of the instrument was performed. The background value was primarily used to ensure that the detector had not become cross-contaminated by any previous use. Background was not subtracted from any measurement.

Daily prior to use and daily following use, each detector was subjected to an Operational Response Check in accordance with procedure ZS-LT-300-001-006, Radiation Surveys of Pipe Interiors Using Sodium/Cesium Iodide Detectors (Reference 12). The Daily Operational Response Check compared the background response and the response to check sources ranges established for normal background and detector source response to ensure that the detector was working properly.

Surveys of the Unit 1 Tendon Tunnel floor drain piping were performed from April 2 through April 4, 2018. The survey was completed in 3 days. The piping was accessed through the floor drains located in the Tendon Tunnel, numbered M18 through M23.

Due to blockages in the piping from debris and water, only 207 of piping was accessible for survey. The distance between static measurements was reduced from 10 to 3 (M18 and M19) or 5 (M22, M23) to insure enough data points were collected to meet the 10%

areal coverage requirement from the survey design. A total of 58 readings were obtained.

The 58 readings obtained represent 11.1% of the pipe interior surface. Table 7 summarizes the data collected:

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FSS RELEASE RECORD U1 TENDON TUNNEL FLOOR DRAIN PIPE SURVEY UNIT 06211 Table 7 - Survey Data Collected

1. of Length Pipe run measurements Comment surveyed taken Debris blocked the line at 50; 2 additional readings taken with access M23 55 ft. 13 at M22, 75 and 70 .

All readings taken at 5 intervals.

Pipe entered at M22 toward M21.

M22 60 ft. 13, 1QC Debris blocked the line at 60.

Readings taken at 5 intervals.

Pipe entered at M19 towards M18.

M18 48 ft. 16, 1QC Debris blocked the line at 48.

Readings taken at 3 intervals.

Pipe entered at M20 towards M19.

M19 44 ft. 16, 1QC Debris blocked the line at 44.

Readings taken at 3 intervals.

M20, M21 0 ft. 0 Filled with water Total 207 ft. 58, 3QC The instrument and detector used for this survey are presented in Table 8. The instrument and detector were verified to be properly calibrated prior to use.

Table 8 - Instrument and detector Instrument/Detector Calibration Due Serial #

Type Date Ludlum 2350-1 304708 05/01/18 Ludlum 44-159 PR327896 05/01/18 Daily prior to use (Pre-Test) and daily upon completion of surveys (Post-Test), response checks were performed in accordance with procedure ZS-LT-300-001-006 for each detector and data logger pairing. In addition, all instruments and detectors were physically inspected for mechanical damage as part of the response check process.

During the FSS, no instances were encountered where an instrument and/or detector failed a Pre or Post response check or were found to be physically damaged during the inspection.

7. SURVEY RESULTS After completion of the FSS measurements in the pipe, the sample plan was reviewed to confirm the completeness of the survey and the survey data was validated in accordance

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FSS RELEASE RECORD U1 TENDON TUNNEL FLOOR DRAIN PIPE SURVEY UNIT 06211 with procedure ZS-LT-300-001-004, Final Status Survey Data Assessment (Reference 13). Data processing includes converting measurement data into reporting units, validating instrument applicability and sensitivity, calculating relevant statistical quantities, and verification that all DQO have been met. In accordance with the procedure, a preliminary Data Assessment was prepared.

The primary gamma emitting ROC for the FSS of the Tendon Tunnel Floor Drains FSS unit are Co-60, Cs-134 and Cs-137. Ni-63 and Sr-90 are also ROC for the Tendon Tunnel Floor Drains. Ni-63 is inferred from the measured concentration of Co-60, while Sr-90 is inferred from the measured concentration of Cs-137.

All measurements were less than 50% of the OpDCGL, meeting the requirement for a Class 3 area.

The mean of the OpSOF for all 58 samples was 0.184.

The activity in this pipe must also be compared to the OpDCGLB for the building that contains it. According to Table 5-20 of the LTP, the Tendon Tunnel drains are included with both the Containment and Turbine Buildings. One (1) sample had a SOF greater than 1 when compared to the OpDCGLB for the Turbine Building. This one pipe section, M22 was grouted. No dose reduction was claimed as a result of the grouting. The results of this comparison for all other samples show that the SOFs for all samples were below one when compared to the OpDCGLB for both of these buildings The results of the data assessment for the embedded floor drain pipe are provided in Attachment 2. A statistical summary of the data is presented in Table 10.

The data collected passed the Sign Test. The result of the Sign Test is provided in Attachment 3.

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FSS RELEASE RECORD U1 TENDON TUNNEL FLOOR DRAIN PIPE SURVEY UNIT 06211 Table 9 - Unit 1 Tendon Tunnel Floor Drains - Statistical Summary Mean Max Min Standard Base Case Concen- Concen- Concen- Nuclide Deviation DCGLEP Radionuclide tration tration tration Mean SOF (BcSOFEP)

(pCi/m2) (pCi/m2) (pCi/m2) (pCi/m2) (pCi/m2)

Co-60 1.11E+04 4.46E+04 8.52E+03 4.77E+03 1.06E+10 0.0000 Cs-134 1.21E+02 4.85E+02 9.26E+01 5.19E+01 2.04E+09 0.0000 Cs-137 9.08E+05 3.66E+06 6.98E+05 3.91E+05 2.67E+09 0.0001 Ni-63(1) 2.00E+06 8.06E+06 1.54E+06 8.61E+05 2.72E+11 0.0000 Sr-90(1) 1.82E+03 7.31E+03 1.40E+03 7.81E+02 9.70E+07 0.0003 (1) Concentrations for Ni-63 and Sr-90 are inferred Mean BcSOF 0.0004 Assigned Dose 0.0092

8. QUALITY CONTROL In compliance with ZS-LT-01, replicate measurements were performed on 5% of the survey locations chosen at random. Three (3) replicate measurements were taken. Using the acceptance criteria specified ZS-LT-01, Quality Assurance Project Plan (QAPP) for Characterization and Final Status Survey, there was acceptable agreement between the replicate readings and the original readings. Refer to Attachment 4 for quality control analysis results.

9. INVESTIGATIONS AND RESULTS As all measurements in the accessible pipe interior surface area was below a SOF of 0.5, no investigations were required or performed.

10. REMEDIATION AND RESULTS No remediation was performed in this piping survey unit.

11. CHANGES FROM THE SURVEY PLAN The access to the drain piping system was changed. The survey design called for the piping to be accessed from the buttress pits. Instead, an entry was made to the Tendon Tunnel, where the drain piping was accessed through the floor drains in the tunnel.

The isotopic mix listed in the Survey Design was the mix for Containment listed in Table 5.2 of the LTP. It was determined that this was not the correct mix to use for this survey

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FSS RELEASE RECORD U1 TENDON TUNNEL FLOOR DRAIN PIPE SURVEY UNIT 06211 unit, therefore all data assessment was performed using the mix for the Auxiliary Building from Table 5.2.

Because only 207 feet of pipe was accessible for survey, the spacing between static measurements was reduced to ensure enough measurements were obtained to obtain 10%

coverage, from 10 feet to 3 feet in pipe sections M18 and M19 and 5 feet in sections M23 and M22.

12. DATA QUALITY ASSESSMENT (DQA)

In accordance with procedure ZS-LT-300-001-004, the DQOs, sample design, and data were reviewed for completeness, accuracy, and consistency. Documentation was complete and legible. The FSS unit was properly classified as Class 3. All measurement results were individually reviewed and validated. The number of measurements was sufficient to meet the requirement of 10% areal coverage of accessible surfaces. The instrumentation used to perform the FSS were in calibration, capable of detecting the activity with an adequate MDC and successfully response checked prior to and following use. An adequate number of replicate measurements were taken and the results meet the acceptance criteria as specified in the QAPP.

13. ANOMALIES No anomalies were observed during the performance or analyses of the survey.

14. CONCLUSION Fifty Eight (58) static measurements were taken in the Unit 1 Tendon Tunnel Floor Drain piping, taken at 3 or 5-foot intervals. The length of pipe in the Unit 1 Tendon Tunnel Floor Drains was 524.21 linear feet, with the accessible length of pipe being 207 feet; therefore the 10% areal survey coverage required by the survey design was met.

All of the measurements were below a SOF of 0.5, when compared to the OpDCGLEP.

The average OpSOF for the survey unit is 0.0184. The requirements for a Class 3 survey unit have been met.

The Sign Test was passed, and the Null Hypothesis was rejected.

The mean BcSOF for this survey unit is 0.0004. The dose contribution from embedded pipe in Survey Unit #S3-06211AF, Unit 1 Tendon Tunnel 547 ft. Embedded Floor Drain Pipe, is 0.0092 mrem/yr TEDE, based on the average concentration of the ROC in samples used for non-parametric statistical sampling.

Survey Unit #S3-06211AF, Unit 1 Tendon Tunnel 547 ft. Embedded Floor Drain Pipe is acceptable for unrestricted release.

[17]

FSS RELEASE RECORD U1 TENDON TUNNEL FLOOR DRAIN PIPE SURVEY UNIT 06211

15. REFERENCES

1. ZionSolutions procedure ZS-LT-300-001-005, Final Status Survey Data Reporting

2. Zion Station Restoration Project License Termination Plan (LTP)

3. ZionSolutions procedure ZS-LT-300-001-001, Final Status Survey Package Development

4. NUREG-1575, Revision 1, Multi-Agency Radiation Survey and Site Investigation Manual (MARSSIM)

5. ZionSolutions procedure ZS-LT-300-001-002, Survey Unit Classification

6. Zion Station Historical Site Assessment (HSA)

7. ZionSolutions TSD 14-016, Description of Embedded Piping, Penetrations, and Buried Pipe to Remain in Zion End State

8. ZionSolutions TSD 17-004, Operational Derived Concentration Guideline Levels for Final Status Survey

9. ZionSolutions TSD 14-019, Radionuclides of Concern for Soil and Basement Fill Model Source Terms

10. ZionSolutions procedure ZS-LT-01, Quality Assurance Project Plan (QAPP) for Characterization and Final Status Survey

11. ZionSolutions procedure ZS-LT-300-001-003, Isolation and Control for Final Status Survey

12. ZionSolutions procedure ZS-LT-300-001-006, Radiation Surveys of Pipe Interiors Using Sodium/Cesium Iodide Detectors

13. ZionSolutions procedure ZS-LT-300-001-004, Final Status Survey Data Assessment

16. ATTACHMENTS Attachment 1 - Figure and Maps Attachment 2 - Sample Data Attachment 3 - Sign Test Attachment 4 - QC Data Attachment 5 - Graphical Presentations

[18]

FSS RELEASE RECORD U1 TENDON TUNNEL FLOOR DRAIN PIPE SURVEY UNIT 06211 ATTACHMENT 1 - FIGURE AND MAPS

[19]

FSS RELEASE RECORD U1 TENDON TUNNEL FLOOR DRAIN PIPE SURVEY UNIT 06211 M23 M22 M18 M21 M19 M20

[20]

FSS RELEASE RECORD U1 TENDON TUNNEL FLOOR DRAIN PIPE SURVEY UNIT 06211 ATTACHMENT 2 - SAMPLE DATA

[21]

FSS RELEASE RECORD U1 TENDON TUNNEL FLOOR DRAIN PIPE SURVEY UNIT 06211 Gross Co-60 Cs-134 Cs-137 Ni-63 Sr-90 Pipe Gamma Co-60 Cs-134 Cs-137 Ni-63 Sr-90 Position Conc. Conc. Conc. Conc. Conc. SOF Section Activity SOF SOF SOF SOF SOF (pCi/m2) 2 (pCi/m ) 2 (pCi/m ) 2 (pCi/m ) 2 (pCi/m ) 2 (pCi/m )

1 1.12E+06 1.35E+04 1.46E+02 1.10E+06 2.43E+06 2.20E+03 6.35E-05 3.59E-06 2.06E-02 4.46E-04 1.14E-03 0.0223 2 7.79E+05 9.40E+03 1.02E+02 7.70E+05 1.70E+06 1.54E+03 4.43E-05 2.50E-06 1.44E-02 3.12E-04 7.94E-04 0.0156 3 9.16E+05 1.11E+04 1.20E+02 9.05E+05 1.99E+06 1.81E+03 5.21E-05 2.95E-06 1.69E-02 3.67E-04 9.33E-04 0.0183 4 9.34E+05 1.13E+04 1.22E+02 9.23E+05 2.03E+06 1.85E+03 5.32E-05 3.00E-06 1.73E-02 3.74E-04 9.51E-04 0.0187 5 9.62E+05 1.16E+04 1.26E+02 9.51E+05 2.10E+06 1.90E+03 5.48E-05 3.09E-06 1.78E-02 3.85E-04 9.80E-04 0.0192 6 8.09E+05 9.77E+03 1.06E+02 8.00E+05 1.76E+06 1.60E+03 4.61E-05 2.60E-06 1.50E-02 3.24E-04 8.24E-04 0.0162 M023 7 8.22E+05 9.92E+03 1.08E+02 8.12E+05 1.79E+06 1.62E+03 4.68E-05 2.64E-06 1.52E-02 3.29E-04 8.37E-04 0.0164 8 7.93E+05 9.57E+03 1.04E+02 7.84E+05 1.73E+06 1.57E+03 4.52E-05 2.55E-06 1.47E-02 3.18E-04 8.08E-04 0.0159 9 7.99E+05 9.64E+03 1.05E+02 7.89E+05 1.74E+06 1.58E+03 4.55E-05 2.57E-06 1.48E-02 3.20E-04 8.13E-04 0.0160 10 8.91E+05 1.08E+04 1.17E+02 8.80E+05 1.94E+06 1.76E+03 5.07E-05 2.87E-06 1.65E-02 3.57E-04 9.08E-04 0.0178 11 1.59E+06 1.92E+04 2.08E+02 1.57E+06 3.46E+06 3.14E+03 9.04E-05 5.11E-06 2.94E-02 6.36E-04 1.62E-03 0.0317 12 8.54E+05 1.03E+04 1.12E+02 8.44E+05 1.86E+06 1.69E+03 4.86E-05 2.74E-06 1.58E-02 3.42E-04 8.70E-04 0.0171 13 8.56E+05 1.03E+04 1.12E+02 8.45E+05 1.86E+06 1.69E+03 4.87E-05 2.75E-06 1.58E-02 3.42E-04 8.71E-04 0.0171 1 3.70E+06 4.46E+04 4.85E+02 3.66E+06 8.06E+06 7.31E+03 2.11E-04 1.19E-05 6.85E-02 1.48E-03 3.77E-03 0.0739 2 1.08E+06 1.30E+04 1.41E+02 1.06E+06 2.35E+06 2.13E+03 6.14E-05 3.47E-06 1.99E-02 4.31E-04 1.10E-03 0.0215 3 8.50E+05 1.03E+04 1.12E+02 8.40E+05 1.85E+06 1.68E+03 4.84E-05 2.73E-06 1.57E-02 3.40E-04 8.66E-04 0.0170 4 7.77E+05 9.38E+03 1.02E+02 7.68E+05 1.69E+06 1.54E+03 4.42E-05 2.50E-06 1.44E-02 3.11E-04 7.92E-04 0.0155 5 8.91E+05 1.08E+04 1.17E+02 8.80E+05 1.94E+06 1.76E+03 5.07E-05 2.87E-06 1.65E-02 3.57E-04 9.08E-04 0.0178 6 9.27E+05 1.12E+04 1.22E+02 9.16E+05 2.02E+06 1.83E+03 5.28E-05 2.98E-06 1.71E-02 3.71E-04 9.44E-04 0.0185 M022 7 9.20E+05 1.11E+04 1.21E+02 9.09E+05 2.00E+06 1.82E+03 5.23E-05 2.96E-06 1.70E-02 3.68E-04 9.37E-04 0.0184 8 8.09E+05 9.77E+03 1.06E+02 8.00E+05 1.76E+06 1.60E+03 4.61E-05 2.60E-06 1.50E-02 3.24E-04 8.24E-04 0.0162 9 7.86E+05 9.49E+03 1.03E+02 7.77E+05 1.71E+06 1.55E+03 4.48E-05 2.53E-06 1.45E-02 3.15E-04 8.01E-04 0.0157 10 9.14E+05 1.10E+04 1.20E+02 9.03E+05 1.99E+06 1.81E+03 5.20E-05 2.94E-06 1.69E-02 3.66E-04 9.31E-04 0.0183 11 8.59E+05 1.04E+04 1.13E+02 8.49E+05 1.87E+06 1.70E+03 4.89E-05 2.76E-06 1.59E-02 3.44E-04 8.75E-04 0.0172 12 8.81E+05 1.06E+04 1.15E+02 8.70E+05 1.92E+06 1.74E+03 5.01E-05 2.83E-06 1.63E-02 3.52E-04 8.97E-04 0.0176 13 9.00E+05 1.09E+04 1.18E+02 8.89E+05 1.96E+06 1.78E+03 5.12E-05 2.89E-06 1.67E-02 3.60E-04 9.17E-04 0.0180 1 7.61E+05 9.19E+03 9.99E+01 7.52E+05 1.66E+06 1.50E+03 4.33E-05 2.45E-06 1.41E-02 3.05E-04 7.75E-04 0.0152 M018 2 7.85E+05 9.47E+03 1.03E+02 7.75E+05 1.71E+06 1.55E+03 4.47E-05 2.52E-06 1.45E-02 3.14E-04 7.99E-04 0.0157 3 7.29E+05 8.80E+03 9.57E+01 7.21E+05 1.59E+06 1.44E+03 4.15E-05 2.34E-06 1.35E-02 2.92E-04 7.43E-04 0.0146

[22]

FSS RELEASE RECORD U1 TENDON TUNNEL FLOOR DRAIN PIPE SURVEY UNIT 06211 Gross Pipe Co-60 Cs-134 Cs-137 Ni-63 Sr-90 Co-60 Cs-134 Cs-137 Ni-63 Sr-90 Position Gamma SOF Section Conc. Conc. Conc. Conc. Conc. SOF SOF SOF SOF SOF Activity 4 7.54E+05 9.10E+03 9.89E+01 7.45E+05 1.64E+06 1.49E+03 4.29E-05 2.42E-06 1.40E-02 3.02E-04 7.68E-04 0.0151 5 8.13E+05 9.81E+03 1.07E+02 8.03E+05 1.77E+06 1.61E+03 4.63E-05 2.61E-06 1.50E-02 3.25E-04 8.28E-04 0.0162 6 7.56E+05 9.12E+03 9.92E+01 7.47E+05 1.65E+06 1.49E+03 4.30E-05 2.43E-06 1.40E-02 3.03E-04 7.70E-04 0.0151 7 7.29E+05 8.80E+03 9.57E+01 7.21E+05 1.59E+06 1.44E+03 4.15E-05 2.34E-06 1.35E-02 2.92E-04 7.43E-04 0.0146 8 7.72E+05 9.32E+03 1.01E+02 7.63E+05 1.68E+06 1.53E+03 4.39E-05 2.48E-06 1.43E-02 3.09E-04 7.86E-04 0.0154 9 7.76E+05 9.36E+03 1.02E+02 7.66E+05 1.69E+06 1.53E+03 4.41E-05 2.49E-06 1.43E-02 3.10E-04 7.90E-04 0.0155 10 8.08E+05 9.75E+03 1.06E+02 7.98E+05 1.76E+06 1.60E+03 4.60E-05 2.60E-06 1.49E-02 3.23E-04 8.23E-04 0.0161 11 7.06E+05 8.52E+03 9.26E+01 6.98E+05 1.54E+06 1.40E+03 4.02E-05 2.27E-06 1.31E-02 2.83E-04 7.19E-04 0.0141 12 7.45E+05 8.99E+03 9.78E+01 7.36E+05 1.62E+06 1.47E+03 4.24E-05 2.40E-06 1.38E-02 2.98E-04 7.59E-04 0.0149 13 7.44E+05 8.97E+03 9.75E+01 7.35E+05 1.62E+06 1.47E+03 4.23E-05 2.39E-06 1.38E-02 2.98E-04 7.57E-04 0.0149 14 7.97E+05 9.62E+03 1.05E+02 7.87E+05 1.74E+06 1.57E+03 4.54E-05 2.56E-06 1.47E-02 3.19E-04 8.12E-04 0.0159 15 7.19E+05 8.67E+03 9.43E+01 7.10E+05 1.56E+06 1.42E+03 4.09E-05 2.31E-06 1.33E-02 2.88E-04 7.32E-04 0.0144 16 7.83E+05 9.44E+03 1.03E+02 7.73E+05 1.70E+06 1.55E+03 4.46E-05 2.52E-06 1.45E-02 3.13E-04 7.97E-04 0.0156 1 1.06E+06 1.28E+04 1.39E+02 1.04E+06 2.30E+06 2.09E+03 6.01E-05 3.40E-06 1.95E-02 4.23E-04 1.08E-03 0.0211 2 9.64E+05 1.16E+04 1.26E+02 9.52E+05 2.10E+06 1.90E+03 5.49E-05 3.10E-06 1.78E-02 3.86E-04 9.82E-04 0.0193 3 8.82E+05 1.06E+04 1.16E+02 8.72E+05 1.92E+06 1.74E+03 5.02E-05 2.84E-06 1.63E-02 3.53E-04 8.99E-04 0.0176 4 8.34E+05 1.01E+04 1.09E+02 8.24E+05 1.82E+06 1.65E+03 4.75E-05 2.68E-06 1.54E-02 3.34E-04 8.50E-04 0.0167 5 9.34E+05 1.13E+04 1.22E+02 9.23E+05 2.03E+06 1.85E+03 5.32E-05 3.00E-06 1.73E-02 3.74E-04 9.51E-04 0.0187 6 9.20E+05 1.11E+04 1.21E+02 9.09E+05 2.00E+06 1.82E+03 5.23E-05 2.96E-06 1.70E-02 3.68E-04 9.37E-04 0.0184 7 1.02E+06 1.24E+04 1.34E+02 1.01E+06 2.23E+06 2.02E+03 5.83E-05 3.29E-06 1.90E-02 4.10E-04 1.04E-03 0.0205 8 8.43E+05 1.02E+04 1.11E+02 8.33E+05 1.84E+06 1.67E+03 4.80E-05 2.71E-06 1.56E-02 3.38E-04 8.59E-04 0.0168 M019 9 8.68E+05 1.05E+04 1.14E+02 8.58E+05 1.89E+06 1.72E+03 4.94E-05 2.79E-06 1.61E-02 3.47E-04 8.84E-04 0.0173 10 7.67E+05 9.25E+03 1.01E+02 7.57E+05 1.67E+06 1.51E+03 4.36E-05 2.46E-06 1.42E-02 3.07E-04 7.81E-04 0.0153 11 1.06E+06 1.28E+04 1.39E+02 1.05E+06 2.30E+06 2.09E+03 6.02E-05 3.40E-06 1.96E-02 4.24E-04 1.08E-03 0.0211 12 9.84E+05 1.19E+04 1.29E+02 9.72E+05 2.14E+06 1.94E+03 5.60E-05 3.16E-06 1.82E-02 3.94E-04 1.00E-03 0.0197 13 9.70E+05 1.17E+04 1.27E+02 9.58E+05 2.11E+06 1.92E+03 5.52E-05 3.12E-06 1.79E-02 3.88E-04 9.87E-04 0.0194 14 8.61E+05 1.04E+04 1.13E+02 8.51E+05 1.87E+06 1.70E+03 4.90E-05 2.77E-06 1.59E-02 3.45E-04 8.77E-04 0.0172 15 9.06E+05 1.09E+04 1.19E+02 8.95E+05 1.97E+06 1.79E+03 5.15E-05 2.91E-06 1.68E-02 3.62E-04 9.22E-04 0.0181 16 8.75E+05 1.06E+04 1.15E+02 8.65E+05 1.91E+06 1.73E+03 4.98E-05 2.81E-06 1.62E-02 3.50E-04 8.91E-04 0.0175

[23]

FSS RELEASE RECORD U1 TENDON TUNNEL FLOOR DRAIN PIPE SURVEY UNIT 06211 ATTACHMENT 3 - SIGN TEST

[24]

FSS RELEASE RECORD U1 TENDON TUNNEL FLOOR DRAIN PIPE SURVEY UNIT 06211 Pipe Co-60 Cs-134 Cs-137 Ni-63 Sr-90 SOF Position 1-Ws Sign Section SOF SOF SOF SOF SOF (Ws) 1 6.35E-05 3.59E-06 2.06E-02 4.46E-04 1.14E-03 0.0223 0.98 +1 2 4.43E-05 2.50E-06 1.44E-02 3.12E-04 7.94E-04 0.0156 0.98 +1 3 5.21E-05 2.95E-06 1.69E-02 3.67E-04 9.33E-04 0.0183 0.98 +1 4 5.32E-05 3.00E-06 1.73E-02 3.74E-04 9.51E-04 0.0187 0.98 +1 5 5.48E-05 3.09E-06 1.78E-02 3.85E-04 9.80E-04 0.0192 0.98 +1 6 4.61E-05 2.60E-06 1.50E-02 3.24E-04 8.24E-04 0.0162 0.98 +1 M023 7 4.68E-05 2.64E-06 1.52E-02 3.29E-04 8.37E-04 0.0164 0.98 +1 8 4.52E-05 2.55E-06 1.47E-02 3.18E-04 8.08E-04 0.0159 0.98 +1 9 4.55E-05 2.57E-06 1.48E-02 3.20E-04 8.13E-04 0.0160 0.98 +1 10 5.07E-05 2.87E-06 1.65E-02 3.57E-04 9.08E-04 0.0178 0.98 +1 11 9.04E-05 5.11E-06 2.94E-02 6.36E-04 1.62E-03 0.0317 0.97 +1 12 4.86E-05 2.74E-06 1.58E-02 3.42E-04 8.70E-04 0.0171 0.98 +1 13 4.87E-05 2.75E-06 1.58E-02 3.42E-04 8.71E-04 0.0171 0.98 +1 1 2.11E-04 1.19E-05 6.85E-02 1.48E-03 3.77E-03 0.0739 0.93 +1 2 6.14E-05 3.47E-06 1.99E-02 4.31E-04 1.10E-03 0.0215 0.98 +1 3 4.84E-05 2.73E-06 1.57E-02 3.40E-04 8.66E-04 0.0170 0.98 +1 4 4.42E-05 2.50E-06 1.44E-02 3.11E-04 7.92E-04 0.0155 0.98 +1 5 5.07E-05 2.87E-06 1.65E-02 3.57E-04 9.08E-04 0.0178 0.98 +1 6 5.28E-05 2.98E-06 1.71E-02 3.71E-04 9.44E-04 0.0185 0.98 +1 M022 7 5.23E-05 2.96E-06 1.70E-02 3.68E-04 9.37E-04 0.0184 0.98 +1 8 4.61E-05 2.60E-06 1.50E-02 3.24E-04 8.24E-04 0.0162 0.98 +1 9 4.48E-05 2.53E-06 1.45E-02 3.15E-04 8.01E-04 0.0157 0.98 +1 10 5.20E-05 2.94E-06 1.69E-02 3.66E-04 9.31E-04 0.0183 0.98 +1 11 4.89E-05 2.76E-06 1.59E-02 3.44E-04 8.75E-04 0.0172 0.98 +1 12 5.01E-05 2.83E-06 1.63E-02 3.52E-04 8.97E-04 0.0176 0.98 +1 13 5.12E-05 2.89E-06 1.67E-02 3.60E-04 9.17E-04 0.0180 0.98 +1 1 4.33E-05 2.45E-06 1.41E-02 3.05E-04 7.75E-04 0.0152 0.98 +1 2 4.47E-05 2.52E-06 1.45E-02 3.14E-04 7.99E-04 0.0157 0.98 +1 3 4.15E-05 2.34E-06 1.35E-02 2.92E-04 7.43E-04 0.0146 0.99 +1 4 4.29E-05 2.42E-06 1.40E-02 3.02E-04 7.68E-04 0.0151 0.98 +1 5 4.63E-05 2.61E-06 1.50E-02 3.25E-04 8.28E-04 0.0162 0.98 +1 6 4.30E-05 2.43E-06 1.40E-02 3.03E-04 7.70E-04 0.0151 0.98 +1 7 4.15E-05 2.34E-06 1.35E-02 2.92E-04 7.43E-04 0.0146 0.99 +1 8 4.39E-05 2.48E-06 1.43E-02 3.09E-04 7.86E-04 0.0154 0.98 +1 M018 9 4.41E-05 2.49E-06 1.43E-02 3.10E-04 7.90E-04 0.0155 0.98 +1 10 4.60E-05 2.60E-06 1.49E-02 3.23E-04 8.23E-04 0.0161 0.98 +1 11 4.02E-05 2.27E-06 1.31E-02 2.83E-04 7.19E-04 0.0141 0.99 +1 12 4.24E-05 2.40E-06 1.38E-02 2.98E-04 7.59E-04 0.0149 0.99 +1 13 4.23E-05 2.39E-06 1.38E-02 2.98E-04 7.57E-04 0.0149 0.99 +1 14 4.54E-05 2.56E-06 1.47E-02 3.19E-04 8.12E-04 0.0159 0.98 +1 15 4.09E-05 2.31E-06 1.33E-02 2.88E-04 7.32E-04 0.0144 0.99 +1 16 4.46E-05 2.52E-06 1.45E-02 3.13E-04 7.97E-04 0.0156 0.98 +1 1 6.01E-05 3.40E-06 1.95E-02 4.23E-04 1.08E-03 0.0211 0.98 +1 2 5.49E-05 3.10E-06 1.78E-02 3.86E-04 9.82E-04 0.0193 0.98 +1 3 5.02E-05 2.84E-06 1.63E-02 3.53E-04 8.99E-04 0.0176 0.98 +1 M019 4 4.75E-05 2.68E-06 1.54E-02 3.34E-04 8.50E-04 0.0167 0.98 +1 5 5.32E-05 3.00E-06 1.73E-02 3.74E-04 9.51E-04 0.0187 0.98 +1 6 5.23E-05 2.96E-06 1.70E-02 3.68E-04 9.37E-04 0.0184 0.98 +1 7 5.83E-05 3.29E-06 1.90E-02 4.10E-04 1.04E-03 0.0205 0.98 +1

[25]

FSS RELEASE RECORD U1 TENDON TUNNEL FLOOR DRAIN PIPE SURVEY UNIT 06211 Pipe Co-60 Cs-134 Cs-137 Ni-63 Sr-90 SOF Position 1-Ws Sign Section SOF SOF SOF SOF SOF (Ws) 8 4.80E-05 2.71E-06 1.56E-02 3.38E-04 8.59E-04 0.0168 0.98 +1 9 4.94E-05 2.79E-06 1.61E-02 3.47E-04 8.84E-04 0.0173 0.98 +1 10 4.36E-05 2.46E-06 1.42E-02 3.07E-04 7.81E-04 0.0153 0.98 +1 11 6.02E-05 3.40E-06 1.96E-02 4.24E-04 1.08E-03 0.0211 0.98 +1 12 5.60E-05 3.16E-06 1.82E-02 3.94E-04 1.00E-03 0.0197 0.98 +1 13 5.52E-05 3.12E-06 1.79E-02 3.88E-04 9.87E-04 0.0194 0.98 +1 14 4.90E-05 2.77E-06 1.59E-02 3.45E-04 8.77E-04 0.0172 0.98 +1 15 5.15E-05 2.91E-06 1.68E-02 3.62E-04 9.22E-04 0.0181 0.98 +1 16 4.98E-05 2.81E-06 1.62E-02 3.50E-04 8.91E-04 0.0175 0.98 +1 Number of Measurements = 58 Type I Error = .05 Number of Positive Differences (S+) = 58 Critical Value = 35 Survey unit MEETS the Acceptance Criteria YES

[26]

FSS RELEASE RECORD U1 TENDON TUNNEL FLOOR DRAIN PIPE SURVEY UNIT 06211 ATTACHMENT 4 - QC DATA

[27]

FSS RELEASE RECORD U1 TENDON TUNNEL FLOOR DRAIN PIPE SURVEY UNIT 06211 Unit 1 Tendon Tunnel Embedded Drain Pipe - QC Agreement Location Reading (CPM) QC Reading (CPM) Ratio QC Pass?

M022 60' 9.00E+05 8.86E+05 1.016 YES M018 45' 7.83E+05 6.69E+05 1.170 YES M019 45' 8.75E+05 9.38E+05 0.934 YES

[28]

FSS RELEASE RECORD U1 TENDON TUNNEL FLOOR DRAIN PIPE SURVEY UNIT 06211 ATTACHMENT 5 - GRAPHICAL PRESENTATIONS

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FSS RELEASE RECORD U1 TENDON TUNNEL FLOOR DRAIN PIPE SURVEY UNIT 06211 QUANTILE PLOT for Gross Gamma Activity Survey Unit: S3-06211 Survey Unit Name: Unit 1 Tendon Tunnel Drains Embedded Pipe Mean: 9.20E+05 pCi/m2 Quantile Plot For Gross Gamma Activity 4.21E+06 3.71E+06 Gross Activity (pCi/m2) 3.21E+06 2.71E+06 2.21E+06 1.71E+06 1.21E+06 7.06E+05 0% 10% 20% 30% 40% 50% 60% 70% 80% 90% 100%

Percentage

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FSS RELEASE RECORD U1 TENDON TUNNEL FLOOR DRAIN PIPE SURVEY UNIT 06211 Histogram for Gross Gamma Activity Survey Unit: L3-06211 Survey Unit Name: Unit 1 Tendon Tunnel Floor Drains Mean: 9.20E+05 pCi/g Median: 8.55E+05 pCi/g ST DEV: 3.95E+05 Skew: 6.389 Histogram 60 55 50 40 Frequency 30 20 10 1 1 0 0 0 0 1 0

1.08E+06 1.45E+06 1.83E+06 2.20E+06 2.58E+06 2.95E+06 3.33E+06 3.70E+06 Bin Upper Observation Observation Value Frequency  %

1.08E+06 55 94.8%

1.45E+06 1 1.7%

1.83E+06 1 1.7%

2.20E+06 0 0.0%

2.58E+06 0 0.0%

2.95E+06 0 0.0%

3.33E+06 0 0.0%

3.70E+06 1 1.7%

TOTAL 58 100%

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FSS RELEASE RECORD U1 TENDON TUNNEL FLOOR DRAIN PIPE SURVEY UNIT 06211 Retrospective Power Curve for Survey Unit 06211

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