ML19077A066

Final Status Survey (FSS) Final Report - Phase 2, Part 1, Waste Water Treatment Facility Survey Unit 09100

ML19077A066
Person / Time
Site:	Zion  File:ZionSolutions icon.png
Issue date:	01/07/2019
From:	Massengill R ZionSolutions
To:	Office of Nuclear Material Safety and Safeguards
References
ZS-2019-0017
Download: ML19077A066 (605)

Text

ZION STATION RESTORATION PROJECT FINAL STATUS SURVEY RELEASE RECORD WASTE WATER TREATMENT FACILITY SURVEY UNIT 09100

FSS RELEASE RECORD WASTE WATER TREATMENT FACILITY SURVEY UNIT 09100 1/7/2019 PREPARED BY / DATE: ______________________________________

R. Massengill, Radiological Engineer 1/7/2019 REVIEWED BY / DATE: ______________________________________

P. Giza, Radiological Engineer 1/7/2019 APPROVED BY / DATE: ______________________________________

D. Wojtkowiak, C/LT Manager

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FSS RELEASE RECORD WASTE WATER TREATMENT FACILITY SURVEY UNIT 09100 TABLE OF CONTENTS

1. EXECUTIVE

SUMMARY

................................................................................................ 7

2. SURVEY UNIT DESCRIPTION ...................................................................................... 8

3. CLASSIFICATION BASIS.............................................................................................. 10

4. DATA QUALITY OBJECTIVES (DQO) ...................................................................... 11

5. SURVEY DESIGN ............................................................................................................ 15

6. SURVEY IMPLEMENTATION ..................................................................................... 21

7. SURVEY RESULTS ......................................................................................................... 22

8. QUALITY CONTROL..................................................................................................... 31

9. INVESTIGATIONS AND RESULTS ............................................................................. 32

10. REMEDIATION AND RESULTS .................................................................................. 32

11. CHANGES FROM THE FINAL STATUS SURVEY PLAN ....................................... 32

12. DATA QUALITY ASSESSMENT (DQA) ..................................................................... 32

13. ANOMALIES .................................................................................................................... 33

14. COMPLIANCE EQUATION .......................................................................................... 33

15. CONCLUSION ................................................................................................................. 35

16. REFERENCES .................................................................................................................. 35

17. ATTACHMENTS ............................................................................................................. 36 ATTACHMENT 1 .............................................................................................................. 37 ATTACHMENT 2 .............................................................................................................. 40 ATTACHMENT 3 .............................................................................................................. 62 ATTACHMENT 4 .............................................................................................................. 65 ATTACHMENT 5 .............................................................................................................. 70 ATTACHMENT 6 .............................................................................................................. 76 ATTACHMENT 7 .............................................................................................................. 95

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FSS RELEASE RECORD WASTE WATER TREATMENT FACILITY SURVEY UNIT 09100 LIST OF FIGURES Figure 1 - Waste Water Treatment Facility Top View from Drawing B-1024 ................................ 9 Figure 2 - Waste Water Treatment Facility after Demolition ......................................................... 10 Figure 3 - Waste Water Treatment Facility Conditions at FSS ...................................................... 10 LIST OF TABLES Table 1 - Dose Significant Radionuclides and Mixture .................................................................. 13 Table 2 - Base Case DCGLs for WWTF (BcDCGLB) from LTP Chapter 5, Table 5-3 ................ 14 Table 3 - Operational DCGLs (OpDCGLB) for WWTF from LTP Chapter 5, Table 5-4 .............. 15 Table 4 - Number of ISOCS Measurements per FSS Unit based on Areal Coverage .................... 17 Table 5 - Adjusted(1) Minimum Number of ISOCS Measurements per FSS Unit ........................ 18 Table 6 - Surrogate Ratios for Auxiliary Building ......................................................................... 18 Table 7 - Investigation Levels......................................................................................................... 20 Table 8 - Synopsis of Survey Design .............................................................................................. 20 Table 9 - Waste Water Treatment Facility - Measured Concentrations of ROC for FSS .............. 24 Table 10 - Waste Water Treatment Facility - Statistical Quantities - Systematic Measurement Population .............................................................................................. 27 Table 11 - WWTF FSS Concrete Core Sample Analysis - Surface to 0.5 inch Depth .................. 29

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FSS RELEASE RECORD WASTE WATER TREATMENT FACILITY SURVEY UNIT 09100 LIST OF ACRONYMS AND ABBREVIATIONS ALARA As Low As Reasonably Achievable AMCG Average Member of the Critical Group BcDCGL Base Case Derived Concentration Guideline Level BcSOF Base Case Sum-of-Fraction BFM Basement Fill Model CoC Chain-of-Custody DQA Data Quality Assessment DQO Data Quality Objective DCGL Derived Concentration Guideline Level EMC Elevated Measurement Comparison FSS Final Status Survey GPS Global Positioning System HTD Hard-to-Detect IC Insignificant Contributor LTP License Termination Plan LBGR Lower Bound of the Gray Region MARSSIM Multi-Agency Radiation Survey and Site Investigation Manual MDC Minimum Detectable Concentration MDCR Minimal Detectable Count Rate NAD North American Datum NaI Sodium Iodide OpDCGL Operational Derived Concentration Guideline Level OpSOF Operational Sum-of-Fraction QAPP Quality Assurance Project Plan QC Quality Control RE Radiological Engineer ROC Radionuclides of Concern

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FSS RELEASE RECORD WASTE WATER TREATMENT FACILITY SURVEY UNIT 09100 SOF Sum-of-Fraction TEDE Total Effective Dose Equivalent UBGR Upper Bound of the Gray Region UCL Upper Confidence Level USNRC United States Nuclear Regulatory Commission VCC Vertical Concrete Cask VSP Visual Sample Plan WWTF Waste Water Treatment Facility ZNPS Zion Nuclear Power Station ZSRP Zion Station Restoration Project

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FSS RELEASE RECORD WASTE WATER TREATMENT FACILITY SURVEY UNIT 09100

1. EXECUTIVE

SUMMARY

This Final Status Survey (FSS) Release Record for Survey Unit #B1-09100AF, Waste Water Treatment Facility (WWTF), has been generated for the Zion Station Restoration Project (ZSRP) 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).

Final Status Survey (FSS) sample plans for each of these survey units were 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).

In accordance with ZSRP LTP Chapter 5, section 5.5.2.1.2 and Table 5-19, the WWTF survey unit has a MARSSIM classification of 1. Survey plans were designed based upon use of the Sign Test as the nonparametric statistical test for compliance. Both the Type I

() and Type II () decision error rates were set at 0.05. The Canberra In Situ Object Counting System (ISOCS) was selected as the primary instrument used to perform FSS of the WWTF survey unit. As a Class 1 survey unit, ISOCS measurement locations were designated to ensure 100% areal coverage of all accessible structural surfaces within the survey unit.

Based on a measurement Field-of-View (FOV) of 28 m2 for each ISOCS measurement, it was initially determined that fifty four (54) ISOCS measurements were required to ensure 100% areal coverage of the WWTF.

Minor modifications to the designed sample plan were required based on the as-left conditions of the WWTF demolition to the 588 ft. elevation. Some measurement locations were eliminated due to the final configuration of the WWTF. Additional measurement locations were added to ensure 100% areal coverage within the survey unit. After making those adjustments to the sample plan, a total of seventy-four (74) ISOCS measurements were taken; seventy (70) systematic measurements on the floor, walls, and sumps in addition to four (4) QC samples.

The results for all ISOCS measurements taken in the WWTF survey unit indicate that the Sum-of-Fractions (SOF) for each measurement, considering the concentration of all applicable ROC, either by direct measurement or by inference, is less than one (1) when applying the respective Operational Derived Concentration Guideline Levels (OpDCGL) for the Containment Basements (ZionSolutions Technical Support Document (TSD)17-004, Operational Derived Concentration Guideline Levels for FSS [Reference 5]).

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FSS RELEASE RECORD WASTE WATER TREATMENT FACILITY SURVEY UNIT 09100 Therefore the null hypothesis is rejected and the WWTF survey unit (Survey Unit #B1-09100AF) is acceptable for unrestricted release.

2. SURVEY UNIT DESCRIPTION The Wastewater Treatment Facility (WWTF) was designed to treat non-radioactive and low-level radioactive liquid from Zion Nuclear Power Station (ZNPS) sources including building roof run-off and the Turbine Building Fire Sump, which received liquid waste from the Turbine Building Equipment and Floor Drains, and the Fuel Pool Cooling Tower Blowdown. The WWTF was designed to remove suspended solids and oil to ensure compliance with the facility National Pollutant Discharge Elimination System (NPDES) permit. Since the wastewater discharge rates were variable, an equalization tank was installed. The WWTF also included other equipment such as mixing tanks, mixers, oil skimmers, flocculators, oil coalescers, clarifiers, sludge drying beds and filters. Discharge from the WWTF was by gravity to the Forebay. During ZNPS operations, liquid waste with detectable low-level radioactive contamination was processed by the WWTF.

Consequently, the internal surfaces of the WWTF systems were considered to be potentially contaminated.

All systems, component and materials associated with the WWTF that were identified by radiological survey as contaminated with detectable plant-derived radioactive material were removed by ZionSolutions personnel and dispositioned and properly disposed of as radioactive waste. The remaining structure was then made Cold, Dark and Dry. Once this was complete, all remaining commodities and all structural surfaces were demolished to a depth of 3 feet below grade.

Once the remaining concrete structure located below 3 feet below grade (588 foot elevation) has been satisfactorily surveyed and compliance with the unrestricted release criteria has been demonstrated and, contingent upon the completion of confirmatory surveys, the WWTF void will be backfilled using concrete debris suitable for reuse as clean hard fill and/or clean fill to the original site grade and contours. The top 3 feet of fill will be soil only (i.e. concrete clean hard fill will only be utilized as fill up to the 588 foot elevation).

The Waste Water Treatment Facility (WWTF) end state consists of concrete settling and equalization tanks, clarifiers, flocculant (FLOC) and sludge tanks with sloped bottoms as seen in the top view of the WWTF basement in Figure 1. (ZionSolutions TSD 14-014, End State Surface Areas, Volumes, and Source Terms of Ancillary Buildings [Reference 6]).

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FSS RELEASE RECORD WASTE WATER TREATMENT FACILITY SURVEY UNIT 09100 Figure 1 - Waste Water Treatment Facility Top View from Drawing B-1024 The northeast portion of the WWTF contained two (north and south) Clarifiers and Flocculant Tanks and a single Sludge Holding Tank. Each Clarifier consists of a mildly sloped floor and is 8 feet wide. There is a pit with angled east and west walls and a 2.5 feet wide floor. A 6 inch opening in the East wall above the pit allows flow to the Flocculant Tank.

The west wall of the Clarifier Pit has an average width of 2 feet with a depth of approximately 5 feet. The concrete spans the 18 foot, 6 inch width of the structure.

Similarly the East wall of the pit has an average width of 1 foot 6 inches plus 10 inches or 2.33 feet with a depth of 5.67 feet which with a 18 foot, 6 inch width. Between the walls, the pit floor is 2.5 feet long by 18 feet, 6 inch wide and 1 foot thick. The north and south walls of the clarifier are 10 inches thick and the north wall has an additional 10 inches thick outer layer.

The north and south FLOC Tanks are 6 feet long by 8 feet wide and 1.5 feet deep. The west wall has a 6 inch opening and is only 1 foot deep.

The Sludge Holding Tank wall slopes from the 587.5 foot elevation to the 583 foot elevation and has a tank interior that is 11 feet by 16 feet 10 inches.

The basic decommissioning end-state for the WWTF is for the walls, floor, and sumps/pits below the 588 foot elevation to remain. Most of the end state concrete below the 588 foot elevation is above the 579 foot water table. However, after FSS is complete, the floors of the structures will be perforated to ensure they can equilibrate with the water table and

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FSS RELEASE RECORD WASTE WATER TREATMENT FACILITY SURVEY UNIT 09100 will not overflow the structure at the 588 foot elevation. Figures 2 and 3 illustrate the WWTF conditions after demolition and prior to FSS.

Figure 2 - Waste Water Treatment Facility after Demolition Figure 3 - Waste Water Treatment Facility Conditions at FSS

3. CLASSIFICATION BASIS The Waste Water Treatment Facility (WWTF) was constructed and placed into service in the fall of 1978. The design purpose of the WWTF was to receive the discharges from the fire sump and the heater bay roof drains. Due to the contamination of the fire sump (as a

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FSS RELEASE RECORD WASTE WATER TREATMENT FACILITY SURVEY UNIT 09100 result of primary to secondary leakage), many portions of the WWTF systems contained trace levels of radioactive contaminants.

Sections of the subfloor on the south side of the building were posted for radioactive materials. Additionally, due to the system design and operation, organic contaminants (mainly turbine oil) were assumed to be present throughout the building and components.

Piping below floor on south side of the building was labeled as radioactive.

The following summary of processes and incidents was obtained from the Zion Station Historical Site Assessment (HSA) (Reference 7) and other sources:

• About 10/1/1978 - the fire sump discharge and the heater bay roof drains were rerouted to the newly completed WWTF in accordance with a commitment to the EPA. The facility was designed to reduce solids in the plant discharge. (NRC IR 78-26/78-26)

• On 11/16/1996 - approximately 1000 gallons of turbine oil was sent to the fire sump and the WWTF. (PIF 96-4264)

• On 12/6/1996 - approximately 100 gallons of turbine oil was sent to the fire sump and the WWTF. (PIF 96-4665)

• 05/22/2017 - approximately 2 gallons of low level radioactive water leaked onto the ground at north end of a tent located north of the WWTF. (Condition Report ES-ZION-CR-2017-0073)

• 05/10/2018 - Routine RP survey (2018-1480) conducted in WWTF indicated contact dose rates up to 88 mRem/hr on a HIC.

• 05/24/2018 - Survey unit area classification revised from Class 3 to Class 1 in LTP to reflect the use of WWTF as a radioactive material storage area.

No initial characterization was performed on the WWTF as the systems remained active throughout decommissioning up to the point of building demolition. Based on the building design basis and the operating history, the WWTF was given an initial classification of Class 3 in the HSA. However, during decommissioning, the facility was used as a radioactive material storage area for unpackaged radioactive wastes.

Consequently, LTP, Revision 2 section 5.5.2.1 and Table 5-18 identifies the WWTF as a Class 1 area requiring 100% areal coverage.

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

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FSS RELEASE RECORD WASTE WATER TREATMENT FACILITY SURVEY UNIT 09100 described in the ZSRP LTP in accordance with MARSSIM. The appropriate design for a given survey is 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 was to demonstrate that the level of residual radioactivity in Survey Unit #B1-09100AF did not exceed the release criteria specified in the LTP and that the potential dose from residual radioactivity was As Low As Reasonably Achievable (ALARA).

ZionSolutions TSD 11-001, Potential Radionuclides of Concern during the Decommissioning of Zion Station (Reference 8) established the basis for an initial suite of potential ROC for the decommissioning of the ZNPS. LTP Chapter 2 provides detailed characterization data that described contamination levels in the Containments and Auxiliary Building, which were the primary source of radioactive contaminants.

ZionSolutions TSD 14-019, Radionuclides of Concern for Soil and Basement Fill Model Source Terms (Reference 9) evaluates the results of the concrete core analysis data from the Containments and Auxiliary Building and refines the initial suite of radionuclides potential ROC by evaluating the dose significance of each radionuclide.

The final Radionuclides-of-Concern (ROC) for the decommissioning of Zion are Co-60, Cs-134 and Cs-137 (as well as Eu-152 and Eu-154 for Containment), which are gamma emitters and Ni-63, Sr-90 and H-3 (applicable only to Containment), which are Hard-to-Detect (HTD) radionuclides. LTP section 5.1 states that HTD concentrations will be inferred using a surrogate approach and the maximum ratios from LTP Chapter 5, Table 5-15 unless area-specific ratios as determined by actual survey data are used in lieu of the maximum ratios.

LTP Chapter 6, section 6.5.2 discusses the process used to derive the ROC for the decommissioning of the ZNPS, including the elimination of insignificant dose contributors from the initial suite consistent with the guidance in Section 3.3 of NUREG-1757. Based upon the analysis of the Auxiliary Building mixture in TSD 14-019, Table 19, it was

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FSS RELEASE RECORD WASTE WATER TREATMENT FACILITY SURVEY UNIT 09100 determined that Co-60, Ni-63, Sr-90, Cs-134 and Cs-137 accounted for 99.5% of all dose in the contaminated concrete mixes. Table 1 presents the ROC for the decommissioning of Auxiliary Building structural surfaces and the normalized mixture fractions based on the radionuclide mixture.

Table 1 - Dose Significant Radionuclides and Mixture

% of Total Activity Radionuclide (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 fundamental precursor to survey design is to establish a relationship between the release criteria and some measurable quantity. This is done through the development of DCGLs.

The DCGLs represent average levels of radioactivity above background levels and are presented in terms of surface or mass activity concentrations. Chapter 6 of the LTP describes in detail the modeling used to develop the DCGLs for structures.

The End State Basements are comprised of steel and/or concrete structures which will be covered by at least three feet of clean soil and physically altered to a condition which would not realistically allow the remaining structures, if excavated, to be occupied. The exposure pathways in the Basement Fill Model (BFM) are associated with residual radioactivity in floors and walls that is released through leaching into water contained in the interstitial spaces of the fill material. The BFM assumes that the inventory of residual radioactivity in a given building is released either instantly or over time by diffusion, depending on whether the activity is surficial or volumetric, respectively. The activity released into the fill water will adsorb onto the clean fill, as a function of the radionuclide-specific distribution coefficients, resulting in equilibrium concentrations between the fill and the water. Consequently, the only potential exposure pathways after backfill, assuming the as-left geometry, are associated with the residual radioactivity in the water contained in the fill.

The final outputs of the BFM are the Basement Derived Concentration Guideline Levels (DCGL), in units of pCi/m2, which are calculated using the BFM Groundwater (GW) and BFM Drilling Spoils Dose Factors. DCGLs are calculated separately for the GW and Drilling Spoils scenarios and for the summation of both scenarios. The summation DCGL

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FSS RELEASE RECORD WASTE WATER TREATMENT FACILITY SURVEY UNIT 09100 is designated as the Base Case DCGL (BcDCGL) and is used during FSS to demonstrate compliance (analogous to the DCGLW as defined in MARSSIM). The BcDCGLs are radionuclide-specific concentrations that represent the 10 CFR 20.1402 dose criterion of 25 mrem/year and are calculated for each ROC and each backfilled Basement. Additional information pertaining to the calculation of DCGLs for basement surfaces is provided in LTP Chapter 6, section 6.6.8.

When applied to structures, the DCGLs are expressed in units of activity per unit of area (pCi/m2). The unity rule is applied when there is more than one ROC. The measurement results for each singular ROC present in the mixture are compared against their respective DCGL to derive a dose fraction.

The BcDCGLs for the unrestricted release of the WWTF is provided in Table 2. The IC dose percentage of 10% was used to adjust the WWTF DCGLs to account for the dose from the eliminated IC radionuclides.

Table 2 - Base Case DCGLs for WWTF (BcDCGLB) from LTP Chapter 5, Table 5-3 Base Case DCGL Radionuclide (pCi/m2)

Co-60 2.83E+07 Ni-63 2.89E+08 Sr-90 1.03E+05 Cs-134 2.31E+06 Cs-137 2.93E+06 Each radionuclide-specific BcDCGL is equivalent to the level of residual radioactivity (above background levels) that could, when considered independently, result in a Total Effective Dose Equivalent (TEDE) of 25 mrem 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 BcDCGLs 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 (OpDCGL) can be related to the BcDCGLs 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 OpDCGL is then used as the DCGL for the FSS design of the survey unit (calculation of surrogate DCGLs, investigations levels, etc.). Details of the OpDCGLs derived for each dose component and the basis for the applied a priori dose fractions are provided in TSD 17-004.

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FSS RELEASE RECORD WASTE WATER TREATMENT FACILITY SURVEY UNIT 09100 The Operational DCGLs for the unrestricted release of the WWTF Survey Unit #B1-09100AF and are provided in Table 3.

Table 3 - Operational DCGLs (OpDCGLB) for WWTF from LTP Chapter 5, Table 5-4 Operational DCGL Radionuclide (pCi/m2)

Co-60 5.43E+06 Ni-63 5.55E+07 Sr-90 1.98E+04 Cs-134 4.44E+05 Cs-137 5.63E+05 Instrument DQOs included a verification of the ability of the survey instrument to detect the radiation(s) of interest relative to the Operational DCGL. The Canberra ISOCS was selected as the primary instrument used to perform FSS of basement surfaces. Response checks were required prior to issuance and after use. Control and accountability of ISOCS units was required to assure data quality.

As part of the DQOs applied to laboratory processes, analysis results were reported as actual calculated results. The actual recorded value was used as the recorded FSS result for measurement and/or sample values that are less than MDC. Negative values were recorded as zero. Results were not reported as less than MDC. Sample report summaries included unique sample identification, analytical method, radionuclide, result, uncertainty, laboratory data qualifiers, units, and the observed MDC.

In accordance with the LTP, for laboratory analysis, MDCs less than 10% of the Operational DCGL were preferable while MDCs up to 50% of the Operational DCGL were acceptable. The maximum acceptable MDC for measurements obtained using field instruments was 50 percent of the applicable Operational DCGL.

5. SURVEY DESIGN Guidance for preparing FSS plans was provided in procedure ZS-LT-300-001-001 Final Status Survey Package Development. The FSS plan uses an integrated sample design that combines scanning surveys and sampling which can be either random or judgmental.

The Canberra ISOCS was selected as the primary instrument for performing FSS of basement surfaces. The ISOCS was selected as the instrument of choice to perform FSS

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FSS RELEASE RECORD WASTE WATER TREATMENT FACILITY SURVEY UNIT 09100 of basement surfaces due to the fact that an ISOCS measurement will provide results that can be used directly to determine total activity with depth in concrete and, the surface area covered by a single ISOCS measurement is large (a nominal FOV of 10-30 m2) which essentially eliminates the need for a scan surveys. In addition, after an ISOCS measurement is collected, it can be tested against a variety of geometry assumptions to address uncertainty in the source term geometry if necessary.

The source term geometry for ISOCS efficiency calibration, i.e., concentration depth profile and areal distribution of the residual radioactivity in structures, is required to generate efficiency curves (i.e., efficiency as a function of energy) for the ISOCS gamma spectroscopy measurements. These are provided in ZionSolutions TSD 14-022 Revision 2 Addendum 1, Use of In-Situ Gamma Spectroscopy for Final Status Survey of End State Structures (Reference 10).

As per TSD 14-022, a contamination depth of 0.5 inches (1.27 cm) was suggested for the WWTF with all the activity associated within the one-half inch layer. For the floors and walls of the WWTF, the Geometry Composer Circular Plane Template was used. A source to detector distance of 3.0 meters was selected. While several geometries where created where the source to detector distance was varied from 1 to 3 meters, only the 3 meter distance was necessary. A 90 degree collimator was used resulting in a six meter diameter field of view (FOV) that comprised 28.3 m2. Measurements that were conducted using the 3 meter source to detector geometry were indicative of surficial contamination.

There are three sumps located within the WWTF of varying dimensions. In addition, the Clarifier, Flocculator Tank and Sludge Holding Tank exhibited geometries that were not well represented by the 3 meter source to detector geometry. To this end, separate geometries were designed for each using the Geometry Composer Room template. This was done to address the anomalies and best represent the geometric dimensions. ISOCS geometries are provided in Attachment 2 of this report.

In section 5.5.2.2 of the LTP, the number of ISOCS measurements required in the WWTF FSS survey unit was calculated as the quotient of the ISOCS FOV divided into the surface area required for areal coverage. Table 4, which is reproduced from LTP Table 5-18, presents the FSS survey unit for the WWTF, the classification based on contamination potential, the surface area to be surveyed and the minimum number of ISOCS measurements based on a measurement FOV of 28 m2.

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FSS RELEASE RECORD WASTE WATER TREATMENT FACILITY SURVEY UNIT 09100 Table 4 - Number of ISOCS Measurements per FSS Unit based on Areal Coverage Minimum Minimum # of Area Areal ISOCS FSS Unit Classification Coverage Measurements (m2) (% of Area) (FOV-28 m2)

WWTF Class 1 1,124 100% 40 To ensure that the number of ISOCS measurements based on the necessary areal coverage in a basement surface FSS unit was sufficient to satisfy a statistically based sample design, a calculation was performed and documented in LTP section 5.5.2.2 to determine sample size using the standard method as presented in MARSSIM. If the sample size based on the statistical design required more ISOCS measurements than the number of ISOCS measurement required by the areal coverage, then the number of ISOCS measurements was adjusted to meet the larger sample size.

Following MARSSIM guidance, the Type I and Type II decision errors were set at 0.05.

The upper boundary of the gray region was set at the Operational DCGLB. The Lower Bound of the Gray Region (LBGR) was set at the expected fraction of 50% of the Operational DCGLB. A reasonable value for sigma () could not be determined based on existing survey data. Therefore, a coefficient of variation of 30% was used in accordance with the guidance in MARSSIM, section 5.5.2.2.

The relative shift (/) was calculated as discussed in LTP section 5.6.4.1.6. The relative shift (/) was greater than three for the FSS unit. Consequently, a value of three (3) was used for the WWTF as the adjusted relative shift (/). From Table 5-5 of MARSSIM, the required number of measurements (N) for use with the Sign Test, using a value of 0.05 for the Type I and Type II decision errors, is 14 measurements for a / value of three (3).

As previously noted, the required areal coverage for a Class 1 basement survey unit is 100%. The LTP required that sufficient measurements be taken in a Class 1 FSS unit to ensure that 100% of the surface area was surveyed (ISOCS FOV overlapped to ensure that there were no un-surveyed corners and gaps). In cases where the physical configuration or measurement geometry makes the acquisition of a 28 m2 FOV difficult or prohibitive, then the FOV for the ISOCS measurement was reduced provided that the adjusted number of samples remained constant and the minimum areal coverage represented by the FSS unit classification was achieved. To ensure that were no un-surveyed corners and gaps, the number of measurements that were taken in the WWTF Class 1 FSS unit was adjusted by overlaying the center-point of the 28 m2 FOV for the ISOCS measurement on a 4m x 4m (16 m2) grid system. Table 5, which is reproduced from LTP Table 5-19, presents the adjusted number of ISOCS measurements that will be taken in WWTF FSS survey unit.

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FSS RELEASE RECORD WASTE WATER TREATMENT FACILITY SURVEY UNIT 09100 Table 5 - Adjusted(1) Minimum Number of ISOCS Measurements per FSS Unit Required Adjusted # of Adjusted Adjusted Areal ISOCS Areal Areal FSS Unit Classification Coverage Measurements Coverage Coverage (m2) (FOV-28 m2) (m2) (% of Area)

WWTF Class 1 1,124 71(1) 1,124 100%

(1) Adjusted to ensure number of measurements that will be taken in Class 1 FSS units will ensure 100% areal coverage, including overlap to ensure that there are no un-surveyed corners and gaps (FOV based on a 4m x 4m grid system).

When the survey grids were established in the WWTF, obstacles and physical constraints were encountered that prompted further adjustments to the number of samples and the FOV. Some measurements were not feasible and other measurement locations were added. After adjustments to the survey design, a total of seventy-five (75) ISOCS measurements were taken in the WWTF.

The DQO process determined that Co-60, Ni-63, Sr-90, Cs-134 and Cs-137 would be the ROC in the WWTF FSS survey unit #B1-09100AF. During FSS, concentrations for HTD ROC Ni-63 and Sr-90 were to be inferred using a surrogate approach. Cs-137 is the principle surrogate radionuclide for Sr-90 and 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 for the WWTF was calculated in TSD 14-019 and are presented in LTP Table 5-15 and Table 6 below. The maximum ratios were to be used to infer HTD concentrations during FSS unless area specific ratios were determined.

Table 6 - Surrogate Ratios for Auxiliary Building 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 For the FSS of Survey Unit #B1-09100AF, the surrogate Operational DCGLs for Co-60 and Cs-137 were computed based on the maximum ratios from Table 6. The equation for calculating a surrogate DCGL is as follows:

Equation 1 1

=

1 2 3

+ + +

2 3 Where: DCGLSur = Surrogate radionuclide DCGL DCGL2,3n = DCGL for radionuclides to be represented by the surrogate Rn = Ratio of concentration (or nuclide mixture fraction) of

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FSS RELEASE RECORD WASTE WATER TREATMENT FACILITY SURVEY UNIT 09100 radionuclide n to surrogate radionuclide Using the Operational DCGLs for the WWTF presented in Table 3 and the maximum ratios from Table 6, the following surrogate calculations were performed for FSS unit

1. B1-09100AF; Equation 2 1

(137) = = 5.33 + 05 /2 1 0.002

+

5.63 + 05(137) 1.98 + 04(90)

The surrogate Operational DCGL that was used for Cs-137 in FSS unit #B1-09100AF for direct comparison of sample results to demonstrate compliance is 5.33E+05 Ci/m2.

Equation 3 1

(60) = = 2.91 + 05 /2 1 180.450

+

5.43 + 06(60) 5.55 + 07(63)

The surrogate Operational DCGL that was used for Co-60 in FSS unit #B1-09100AF for direct comparison of sample results to demonstrate compliance is 2.91E+05 Ci/m2.

LTP section 5.1 discusses the commitment to acquire concrete core samples at 10% of the locations where an ISOCS measurement was collected with the locations selected at random. Only HTD radionuclides included as ROC (Ni-63, Sr-90, for the WWTF) were analyzed in the FSS confirmatory samples. For the WWTF FSS Survey Unit #B1-09100AF, seventy-one (71) ISOCS measurements were required by the survey design.

Consequently, eight (8) concrete core samples were taken and analyzed to meet the requirements of LTP section 5.1.

To demonstrate compliance with the unrestricted release criteria in FSS unit #B1-09100AF, the Sign Test was selected as the non-parametric statistical test. The use of the Sign Test did not require the selection or use of a background reference area, which simplified survey design and implementation. This approach was conservative since it included background Cs-137 as part of the sample set.

The Elevated Measurement Comparison (EMC) does not apply to this survey unit. At ZSRP, EMC only applies to soils as all other media (structural surfaces, embedded pipe, buried pipe and penetrations) will be remediated to their applicable Base Case DCGL.

A Prospective Power Curve was generated using COMPASS, a software package developed under the sponsorship of the United States Nuclear Regulatory Commission (USNRC) for implementation of the MARSSIM in support of the decommissioning

[19]

FSS RELEASE RECORD WASTE WATER TREATMENT FACILITY SURVEY UNIT 09100 license termination rule (10CFR20, Subpart E). The result of the COMPASS computer run showed adequate power for the survey design (see Attachment 5).

For this Class 1 basement structure survey unit, the Investigation Levels for ISOCS measurement results are those levels specified in LTP Chapter 5, Table 5-25 and are reproduced below in Table 7.

Table 7 - Investigation Levels Classification Direct Measurement Class 1 >Operational DCGL Table 8 provides a synopsis of the survey designs for FSS unit #B1-09100AF.

Table 8 - Synopsis of Survey Design FEATURE DESIGN CRITERIA BASIS Survey Unit Surface Areas 1,124 m2 LTP Ch. 5, Table 5-19

• UBGR = SOF of 1

• LBGR = SOF of 0.01 Number of Measurements

• Type I error = 0.05 71(1)

(N)

• Type II error = 0.05

• / = 3 (adjusted)

• MARSSIM Table 5.5 100% Areal Coverage Grid Spacing LTP Chapter 5, Sec. 5.5.2.2 (Planned for 28 m2 FOV)

• Co 5.43E+06 pCi/m2

• Ni 5.55E+07 pCi/m2 Operational DCGLs for WWTF OpDCGLB

• Sr 1.98E+04 pCi/m2 (LTP Chapter 5, Table 5-4)

• Cs-134 - 4.44E+05 pCi/m2

• Cs-137 - 5.63E+05 pCi/m2 8 Concrete Core samples HTD ROC Analysis LTP Chapter 5, section 5.1 selected for HTD ROC analysis Investigation Level >Operational DCGL LTP Chapter 5, Table 5-25 2

1,124 m or ~100% areal Scan Survey Area Coverage LTP Chapter 5, Table 5-19 coverage 5 % Duplicate ISOCS QC LTP Chapter 5, Sec. 5.9.3.1 Measurements (1) The number of ISOCS measurements designated in the survey designs is greater than the minimum number required for this survey unit, per Chapter 5 of the LTP, Table 5-19. Seventy-one (71) measurements were required to achieve 100% coverage of the WWTF.

[20]

FSS RELEASE RECORD WASTE WATER TREATMENT FACILITY SURVEY UNIT 09100

6. SURVEY IMPLEMENTATION For Survey Unit #B1-09100AF, compliance with the unrestricted release criteria was demonstrated through a combination of direct measurements using the ISOCS and analysis of concrete core samples obtained from the WWTF. The concrete core data was used to validate the ratios of gamma emitters to HTD ROC.

Remediation was completed on August 14th, 2018. The area was cleaned and turned over to the C/LT group for FSS. A walk-down and turnover survey was satisfactorily performed in the FSS survey unit in accordance with the Isolation and Control requirements of procedure ZS-LT-300-001-003, Isolation and Control for Final Status Survey (Reference 11). The turnover surveys consisted of surveys for loose surface contamination. All smear results were less than 1,000 dpm/100 cm2. The WWTF was deemed acceptable for turnover and FSS commenced August 14th, 2018.

There are several system pipes and penetrations embedded in the concrete basement of the WWTF that must be removed to achieve the desired end-state of the survey unit. While undergoing decommissioning, it was determined that if the pipe and penetrations were removed, the WWTF basement would be susceptible to groundwater intrusion that could not be mitigated or controlled. Therefore, it was decided to forgo removal of the aforementioned piping/penetrations until the FSS of the WWTF structural concrete was complete. Once compliance was demonstrated, the pipe/penetrations were removed in a controlled manner. Surveillances performed on FSS surfaces following pipe/penetration removal demonstrated that there was no cross-contamination during the removal process.

Field Logs (ZS-LT-300-001-001 Attachment 14) were used to document field activities and other information pertaining to the performance of the FSS. Daily briefings were conducted to discuss the expectations for job performance and to review safety aspects of the job.

ZionSolutions TSD 14-022 provides the initial justification for the selection of reasonably conservative geometries for efficiency calibrations for the ISOCS based on the physical conditions of the remediated surface and the anticipated depth and distribution of activity.

All ISOCS measurements were acquired using approved geometries. The number and locations of the ISOCS shots were adjusted to ensure 100% coverage of the surfaces of the WWTF. Complete information pertaining to the ISOCS geometries used for the FSS of the WWTF basement is provided in Attachment 2 of the report.

The ISOCS detector was positioned horizontal or vertical to the surface at the center-point of each selected measurement location. In most cases, the exposed face of the detector was positioned at a distance of 3 meters from the surface with the 90 degree collimation shield installed; this orientation corresponded to a nominal FOV of 28 m2. The detector to

[21]

FSS RELEASE RECORD WASTE WATER TREATMENT FACILITY SURVEY UNIT 09100 source distance was reduced even further to accommodate physical constraints or encountered obstructions. In this case, the FOV was reduced and the number of measurements increased to ensure 100% areal coverage was achieved.

The measured activity for each gamma-emitting ROC (and any other gamma emitting radionuclide that was positively detected by ISOCS) was recorded (in units of pCi/m2).

Background was not subtracted from any measurement. A SOF calculation was performed for each measurement by dividing the reported concentration of each ROC by the Operational DCGL for each ROC to derive an individual ROC fraction. The individual ROC fractions were then summed to provide a total SOF value for the measurement.

On August 16th, 2018 it was observed that during preparations for FSS, the demolition contractor had removed 1.5 feet to 2.5 feet high portions of the north wall resulting in the elimination of five (5) survey locations (#s 46-50). Additionally, location 45 was changed to address one-half of Sump #2 in conjunction with location 68. Additional ISOCS measurements were collected on walls (#s 64-66), in sumps (#s 67-69), and in clarifier/flocculants (#s 71-75) to ensure 100% areal coverage. The addition and subtraction of these measurement locations resulted in seventy (70) systematic ISOCS measurements. FSS of the WWTF was completed on August 22nd, 2018. Graphics in Attachment 1 identifies ISOCS measurement locations and core sample locations in the WWTF.

Four (4) duplicate measurements were taken with the ISOCS in the WWTF at locations 9, 14, 27 and 53. These locations were randomly selected using the Microsoft Excel RANDBETWEEN function. The number of replicate measurements satisfies the requirement that a minimum of 5% percent of the number of measurements that will be used for non-parametric statistical testing be selected for additional QC evaluation.

7. SURVEY RESULTS The SOF or unity rule is applied to the data used for the survey planning, and data evaluation and statistical tests for basement surfaces since multiple radionuclide-specific measurements will be performed or the concentrations inferred based on known relationships. The application of the unity rule serves to normalize the data to allow for an accurate comparison of the various data measurements to the release criteria. When the unity rule is applied, the DCGLw (used for the nonparametric statistical test) becomes one (1). The Base Case basement structure DCGLs (BcDCGLB), are directly analogous to the DCGLW as defined in MARSSIM. The use and application of the unity rule was performed in accordance with section 4.3.3 of MARSSIM.

[22]

FSS RELEASE RECORD WASTE WATER TREATMENT FACILITY SURVEY UNIT 09100 As described in LTP Chapter 5, section 5.10.3.2, the Sign Test was used to evaluate the measured residual radioactivity against the dose criterion. The SOF for each measurement was used as the sum value for the Sign Test. The Sign Test then demonstrated that the mean activity for each ROC was less than the Operational DCGLB at a Type 1 decision error of 0.05.

For building surfaces, areas of elevated activity were defined as any area identified by measurement/sample (systematic or judgmental) that exceeded the Operational DCGL but was less than the Base Case DCGL. Any area that exceeded the Base Case DCGL would have required remediation. The SOF (based on the Operational DCGL) for a systematic or a judgmental measurement/sample(s) can exceed one without remediation as long as the survey unit passes the Sign Test and, the mean SOF (based on the Operational DCGL) for the survey unit does not exceed one. Once the survey data set passes the Sign Test (using Operational DCGLs), then the mean radionuclide activity (pCi/m2) for each ROC from systematic measurements along with any identified elevated areas from systematic and judgmental samples can be used with the Base Case DCGLs to perform a mean SOFB calculation. The dose from residual radioactivity assigned to the FSS unit is the mean SOFB multiplied by 25 mrem/yr.

The measurement population consisted of seventy (70) systematic and four (4) quality control locations using the ISOCS. A summary of the results of the seventy (70) ISOCS measurements taken for non-parametric statistical testing results are provided in Table 9.

The concentrations for Ni-63 and Sr-90 are inferred based on the maximum ratios as specified in LTP Chapter 5, Table 5-15. The complete ISOCS gamma spectroscopy reports are presented in Attachment 6. The basic statistics for the systematic measurements are summarized in Table 10.

[23]

FSS RELEASE RECORD WASTE WATER TREATMENT FACILITY SURVEY UNIT 09100 Table 9 - Waste Water Treatment Facility - Measured Concentrations of ROC for FSS Co-60 (1) Ni-63 (2) Sr-90 (2) Cs-134 Cs-137 (1)

Measurement ID OpSOF (3)

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

B1-09100AF-SFC-001-GD 3.74E+03 6.75E+05 3.04E+01 0.00E+00 1.52E+04 0.04138 B1-09100AF-SFC-002-GD 8.66E+03 1.56E+06 2.92E+01 3.14E+03 1.46E+04 0.06423 B1-09100AF-SFC-003-GD 0.00E+00 0.00E+00 4.64E+00 1.22E+03 2.32E+03 0.00710 B1-09100AF-SFC-004-GD 3.27E+03 5.90E+05 2.22E+01 1.52E+04 1.11E+04 0.06631 B1-09100AF-SFC-005-GD 8.16E+03 1.47E+06 4.00E+01 0.00E+00 2.00E+04 0.06558 B1-09100AF-SFC-006-GD 1.42E+02 2.56E+04 6.86E+01 2.42E+03 3.43E+04 0.07033 B1-09100AF-SFC-007-GD 0.00E+00 0.00E+00 3.70E+01 1.33E+04 1.5E+04 0.06468 B1-09100AF-SFC-008-GD 9.46E+03 1.71E+06 2.14E+01 1.20E+04 1.07E+04 0.07961 B1-09100AF-SFC-009-GD 1.22E+04 2.20E+06 6.30E+00 0.00E+00 3.15E+03 0.04783 B1-09100AF-SFC-010-GD 0.00E+00 0.00E+00 0.00E+00 4.15E+03 0.00E+00 0.00935 B1-09100AF-SFC-011GD 6.65E+03 1.20E+06 4.04E+01 0.00E+00 2.02E+04 0.06077 B1-09100AF-SFC-012-GD 1.83E+03 3.30E+05 4.12E+01 7.52E+03 2.06E+04 0.06189 B1-09100AF-SFC-013-GD 4.99E+04 9.00E+06 3.22E+01 1.53E+04 1.61E+04 0.23611 B1-09100AF-SFC-014-GD 4.03E+03 7.27E+05 5.14E+01 1.63E+04 2.57E+04 0.09880 B1-09100AF-SFC-015-GD 6.59E+03 1.19E+06 1.89E+01 2.37E+04 9.47E+03 0.09380 B1-09100AF-SFC-016-GD 7.57E+03 1.37E+06 1.05E+01 1.03E+04 5.25E+03 0.05906 B1-09100AF-SFC-017-GD 2.95E+03 5.32E+05 0.00E+00 1.96E+04 0.00E+00 0.05428 B1-09100AF-SFC-018-GD 9.74E+03 1.76E+06 1.96E+01 1.24E+03 9.80E+03 0.05465 B1-09100AF-SFC-019-GD 1.60E+04 2.89E+06 3.04E+01 1.35E+04 1.52E+04 0.11391 B1-09100AF-SFC-020-GD 1.34E+04 2.42E+06 3.10E+01 3.01E+04 1.55E+04 0.14293 B1-09100AF-SFC-021-GD 1.08E+04 1.95E+06 2.22E+01 2.51E+04 1.11E+04 0.11447 B1-09100AF-SFC-022-GD 6.81E+03 1.23E+06 0.00E+00 2.63E+04 0.00E+00 0.08263 B1-09100AF-SFC-023-GD 1.50E+04 2.71E+06 2.72E+01 0.00E+00 1.36E+04 0.07706 B1-09100AF-SFC-024-GD 0.00E+00 0.00E+00 9.94E+00 2.39E+04 4.97E+03 0.06316 B1-09100AF-SFC-025-GD 0.00E+00 0.00E+00 5.14E+01 0.00E+00 2.57E+04 0.04824 B1-09100AF-SFC-026-GD 5.07E+02 9.14E+04 3.62E+01 0.00E+00 1.81E+04 0.03572 B1-09100AF-SFC-027-GD 3.96E+03 7.15E+05 5.14E+01 5.46E+03 2.57E+04 0.07415 B1-09100AF-SFC-028-GD 0.00E+00 0.00E+00 3.18E+01 3.20E+04 1.59E+04 0.10192 B1-09100AF-SWC-029-GD 7.57E+03 1.36E+06 1.58E+01 3.72E+03 7.91E+03 0.04923 B1-09100AF-SWC-030-GD 1.66E+04 3.00E+06 1.88E+01 2.11E+04 9.41E+03 0.12222 B1-09100AF-SWC-031-GD 6.02E+03 1.09E+06 0.00E+00 2.33E+04 0.00E+00 0.07316 B1-09100AF-SWC-032-GD 5.40E+03 9.74E+05 1.45E+01 1.59E+04 7.25E+03 0.06797

[24]

FSS RELEASE RECORD WASTE WATER TREATMENT FACILITY SURVEY UNIT 09100 Table 9 (continued) - Waste Water Treatment Facility - Measured Concentrations of ROC for FSS Co-60 (1) Ni-63 (2) Sr-90 (2) Cs-134 Cs-137 (1)

Measurement ID OpSOF (3)

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

B1-09100AF-SWC-033-GD 1.25E+04 2.26E+06 5.48E+01 6.6+03 2.74E+04 0.10924 B1-09100AF-SWC-034-GD 9.80E+03 1.77E+06 2.92E+01 0.00E+00 1.46E+04 0.06108 B1-09100AF-SWC-035-GD 0.00E+00 0.00E+00 2.42E+01 7.44E+03 1.21E+04 0.03947 B1-09100AF-SWC-036-GD 1.83E+04 3.30E+06 0.00E+00 5.98E+03 0.00E+00 0.07634 B1-09100AF-SWC-037-GD 4.06E+04 7.33E+06 1.28E+01 0.00E+00 6.39E+03 0.15148 B1-09100AF-SWC-038-GD 8.42E+03 1.52E+06 2.22E+01 1.30E+04 1.11E+04 0.07904 B1-09100AF-SWC-039-GD 4.01E+03 7.24E+05 3.04E+01 2.61E+03 1.52E+04 0.04819 B1-09100AF-SWC-040-GD 9.47E+02 1.71E+05 4.00E+01 1.91E+04 2.00E+04 0.08382 B1-09100AF-SWC-041-GD 1.42E+04 2.56E+06 0.00E+00 3.82E+04 0.00E+00 0.13482 B1-09100AF-SWC-042-GD 2.51E+03 4.53E+05 0.00E+00 3.70E+04 0.00E+00 0.09196 B1-09100AF-SWC-043-GD 5.76E+03 1.04E+06 0.00E+00 2.10E+04 0.00E+00 0.06709 B1-09100AF-SWC-044-GD 0.00E+00 0.00E+00 5.82E+01 2.00E+04 2.91E+04 0.09967 B1-09100AF-SFC-045-GD 3.75E+03 6.77E+05 2.60E+01 1.78E+04 1.30E+04 0.07738 B1-09100AF-SWC-051-GD 4.43E+03 7.99E+05 3.04E+01 3.14E+04 1.52E+04 0.11447 B1-09100AF-SWC-052-GD 7.03E+03 1.27E+06 3.34E+01 3.91E+03 1.67E+04 0.06431 B1-09100AF-SWC-053-GD 4.35E+02 7.85E+04 1.32E+01 4.04E+03 6.59E+03 0.02296 B1-09100AF-SWC-054-GD 5.13E+03 9.26E+05 3.62E+01 1.15E+04 1.81E+04 0.07750 B1-09100AF-SWC-055-GD 2.38E+04 4.29E+06 1.94E+01 0.00E+00 9.72E+03 0.10001 B1-09100AF-SWC-056-GD 6.57E+03 1.19E+06 0.00E+00 0.00E+00 0.00E+00 0.02257 B1-09100AF-SWC-057-GD 6.86E+03 1.24E+06 0.00E+00 6.28E+03 0.00E+00 0.03771 B1-09100AF-SWC-058-GD 1.11E+04 2.00E+06 2.24E+01 1.82E+04 1.12E+04 0.10015 B1-09100AF-SWC-059-GD 6.31E+03 1.14E+06 2.48E+01 2.69E+04 1.24E+04 0.10554 B1-09100AF-SWC-060-GD 0.00E+00 0.00E+00 0.00E+00 1.85E+04 0.00E+00 0.04167 B1-09100AF-SWC-061-GD 0.00E+00 0.00E+00 4.58E+01 0.00E+00 2.29E+04 0.04299 B1-09100AF-SWC-062-GD 1.19E+04 2.15E+06 2.84E+01 1.77E+04 1.42E+04 0.10740 B1-09100AF-SWC-063-GD 0.00E+00 0.00E+00 2.74E+01 1.28E+04 1.37E+04 0.05455

[25]

FSS RELEASE RECORD WASTE WATER TREATMENT FACILITY SURVEY UNIT 09100 Table 9 (continued) - Waste Water Treatment Facility - Measured Concentrations of ROC for FSS Co-60 (1) Ni-63 (2) Sr-90 (2) Cs-134 Cs-137 (1)

Measurement ID 2 2 2 2 OpSOF (3)

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

B1-09100AF-SWC-064-GD 1.71E+03 3.09E+05 2.84E+00 1.63E+04 1.42E+03 0.04525 B1-09100AF-SWC-065-GD 5.76E+03 1.04E+06 3.28E+01 0.00E+00 1.64E+04 0.05057 B1-09100AF-SWC-066-GD 8.34E+03 1.50E+06 2.96E+01 0.00E+00 1.48E+04 0.05643 B1-09100AF-SFC-067-GD 5.67E+03 1.02E+06 1.87E+01 9.78E+02 9.35E+03 0.03923 B1-09100AF-SFC-068-GD 2.97E+03 5.36E+05 2.30E+01 5.55E+02 1.15E+04 0.03304 B1-09100AF-SFC-069-GD 4.86E+03 8.77E+05 7.78E+00 3.88E+03 3.89E+03 0.03274 B1-09100AF-SFC-070-GD 5.30E+03 9.56E+05 7.40E+00 0.00E+00 3.70E+03 0.02515 B1-09100AF-SFC-071-GD 5.38E+03 9.71E+05 0.00E+00 2.13E+03 0.00E+00 0.02328 B1-09100AF-SFC-072-GD 6.07E+03 1.10E+06 2.46E+01 2.52E+04 1.23E+04 0.10070 B1-09100AF-SFC-073-GD 0.00E+00 0.00E+00 1.62E+01 0.00E+00 8.08E+03 0.01517 B1-09100AF-SFC-074-GD 1.39E+03 2.51E+05 9.46E+00 1.31E+03 4.73E+03 0.01661 B1-09100AF-SFC-075-GD 5.55E+03 1.00E+06 8.36E+00 2.75E+03 4.18E+03 0.03311 Note (1) The surrogate OpDCGL for Cs-137 (inferring Sr-90 at the maximum ratios from LTP Table 5-15) equaled 5.33E+05 pCi/m2 (Equation 2) and the surrogate OpDCGL for Co-60 (inferring Ni-63 at the maximum ratio from LTP Table 5-15) equaled 2.91E+05 pCi/m2 (Equation 3). No ISOCS measurement result for Cs-137 or Co-60 exceeded its respective surrogate OpDCGL value.

Note (2) Inferred concentrations Note (3) Compared against OpDCGL

[26]

FSS RELEASE RECORD WASTE WATER TREATMENT FACILITY SURVEY UNIT 09100 Table 10 - Waste Water Treatment Facility - Statistical Quantities - Systematic Measurement Population Individual Measurement Metrics Total Number of Systematic Measurements = 70 Number of Quality Control Measurements = 4 Number of Judgmental/Investigational Measurements = 0 Total Number of Measurements = 74 Mean Systematic Measurement SOF = 0.01341 Max Individual Systematic Measurement SOF = 0.23611 Number of Systematic Measurements with SOF >1 = 0 Statistical Quantities - Systematic Measurement Population MEAN MEDIAN MAX MIN BcDCGL Avg SOF per Avg Dose per ROC (pCi/m2) (pCi/m2) (pCi/m2) (pCi/m2) (pCi/m2) (pCi/m2) ROC ROC Co-60 7.06E+03 5.61E+03 4.99E+04 0.00E+00 8.38E+03 2.83E+07 0.00025 0.00624 Ni-63 1.27E+06 1.01E+06 9.00E+06 0.00E+00 1.51E+06 2.89E+08 0.00441 0.11023 Sr-90 2.25E+01 2.23E+01 6.86E+01 0.00E+00 1.65E+01 1.03E+05 0.00022 0.00546 Cs-134 1.08E+04 7.02E+03 3.82E+04 0.00E+00 1.07E+04 2.31E+06 0.00469 0.11732 Cs-137 1.12E+04 1.12E+04 3.43E+04 0.00E+00 8.27E+03 2.93E+06 0.00384 0.09596 SOF ASSIGNED TO SURVEY UNIT (SYSTEMATIC AVG.) = 0.01341 DOSE ASSIGNED TO SURVEY UNIT (SYSTEMATIC AVG.) = 0.3352 mrem/yr.

The analytical results (converted to SOF) for all of the measurements taken in the WWTF were less than a SOF of one.

[27]

FSS RELEASE RECORD WASTE WATER TREATMENT FACILITY SURVEY UNIT 09100 A six (6) inch concrete core sample was acquired at the eight (8) concrete core locations that were selected at random. Each core was cut into 1/2 inch pucks. The pucks representing the as left condition of the WWTF concrete to a depth of 1/2 inch at the eight (8) selected locations (see Figure 4), were sent to Eberline Laboratories for analysis results for Sr-90, Ni-63 and gamma spectroscopy.

The analysis results for the eight (8) concrete core pucks taken were received from Eberline on September 3, 2018 and the results are presented in Table 11. Each sample or 1/2-inch puck represents the concrete from the existing surface to a depth of 1/2-inch. Each of the 1st 1/2-inch concrete puck from each of the eight (8) concrete core samples were analyzed for all ROC, including the HTD ROC of Ni-63 and Sr-90. Cs-137 was the only ROC positively detected at concentrations greater than MDC. The maximum concentration observed was 3.81E-01 pCi/g. In accordance with LTP section 5.1, only samples with positive results (detectable concentrations greater than MDC) were assessed for HTD ratios.

[28]

FSS RELEASE RECORD WASTE WATER TREATMENT FACILITY SURVEY UNIT 09100 Table 11 - WWTF FSS Concrete Core Sample Analysis - Surface to 0.5 inch Depth Sample ID Nuclide Result Uncertainty MDA >MDC Ratios (pCi/g) (pCi/g) (pCi/g)

B1-09100AF-SFC-067-CV Co-60 -3.21E-02 1.41E-01 1.81E-01 N Ni-63 6.81E-01 1.77E+00 3.02E+00 N Ni-63/Co-60 = N/A Sr-90 -6.05E-02 3.91E-01 7.09E-01 N (Ni-63/Co-60 not positively detected)

Cs-134 3.78E-02 6.95E-02 1.72E-01 N Sr-90/Cs-137 = N/A Cs-137 -8.69E-02 1.68E-01 2.33E-01 N (Sr-90/Cs-137 not positively detected)

B1-09100AF-SWC-031-CV Co-60 -8.91E-02 1.48E-01 1.99E-01 N Ni-63 8.74E-01 1.66E+00 2.82E+00 N Ni-63/Co-60 = N/A Sr-90 3.99E-01 4.00E-01 6.67E-01 N (Ni-63/Co-60 not positively detected)

Cs-134 7.5E-03 6.34E-02 1.49E-01 N Sr-90/Cs-137 = N/A Cs-137 1.76E-01 1.84E-01 3.04E-01 Y (Sr-90 not positively detected)

B1-09100AF-SFC-001-CV Co-60 6.88E-02 1.44E-01 2.69E-01 N Ni-63 6.03E-01 1.79E+00 3.06E+00 N Ni-63/Co-60 = N/A Sr-90 0.00+00 4.65E-01 8.29E-01 N (Ni-63/Co-60 not positively detected)

Cs-134 -1.32E-02 1.06E-01 2.53E-01 N Sr-90/Cs-137 = N/A Cs-137 4.75E-01 2.54E-01 3.81E-01 Y (Sr-90 not positively detected)

B1-09100AF-SFC-010-CV Co-60 2.45E-02 1.17E-01 1.96E-01 N Ni-63 1.55E+00 1.82E+00 3.06E+00 N Ni-63/Co-60 = N/A Sr-90 -1.49E-01 3.97E-01 7.36E-01 N (Ni-63/Co-60 not positively detected)

Cs-134 3.09E-02 6.51E-02 1.32E-01 N Sr-90/Cs-137 = N/A Cs-137 1.50E-01 1.26E-01 2.01E-01 N (Cs-137/Sr-90 not positively detected)

B1-09100AF-SWC-041-CV Co-60 8.14E-02 1.30E-01 1.71E-01 N Ni-63 1.74E+00 1.84E+00 3.08E+00 N Ni-63/Co-60 = N/A Sr-90 2.69E-01 4.53E-01 7.80E-01 N (Ni-63/Co-60 not positively detected)

Cs-134 -6.54E-01 2.78E-01 2.01E-01 N Sr-90/Cs-137 = N/A Cs-137 -2.85E-03 1.44E-01 2.24E-01 N (Cs-137/Sr-90 not positively detected)

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FSS RELEASE RECORD WASTE WATER TREATMENT FACILITY SURVEY UNIT 09100 Table 11 (continued) - WWTF FSS Concrete Core Sample Analysis - Surface to 0.5 inch Depth B1-09100F-SFC-068-CV Co-60 -1.34E-02 5.26E-02 1.39E-01 N Ni-63 1.41E+00 1.50E+00 2.51E+00 N Ni-63/Co-60 = N/A Sr-90 2.04E-01 3.38E-01 5.81E-01 N (Ni-63/Co-60 not positively detected)

Cs-134 -3.89E-03 6.28E-02 2.06E-01 N Sr-90/Cs-137 = N/A Cs-137 3.66E-01 1.88E-01 2.69E-01 Y (Sr-90 not positively detected)

B1-09100F-SWC-051-CV Co-60 -2.76E-02 1.58E-01 2.36E-01 N Ni-63 1.27E+00 1.79E+00 3.01E+00 N Ni-63/Co-60 = N/A Sr-90 2.08E-01 4.14E-01 7.19E-01 N (Ni-63 not positively detected)

Cs-134 -1.55E-02 5.30E-02 2.36E-01 N Sr-90/Cs-137 = N/A Cs-137 4.90E-01 1.72E-01 2.88E-01 Y (Sr-90 not positively detected)

B1-09100F-SFC-021-CV Co-60 9.18E-02 1.58E-01 2.22E-01 N Ni-63 1.90E+00 1.45E+00 2.41E+00 N Ni-63/Co-60 = N/A Sr-90 4.70E-01 4.35E-01 7.22E-01 N (Ni-63/Co-60 not positively detected)

Cs-134 5.65E-02 8.51E-02 2.18E-01 N Sr-90/Cs-137 = N/A Cs-137 4.31E-01 1.87E-01 3.37E-01 Y (Sr-90 not positively detected)

[30]

FSS RELEASE RECORD WASTE WATER TREATMENT FACILITY SURVEY UNIT 09100

8. QUALITY CONTROL The implementation of required QC measures included the collection of four (4) additional ISOCS measurements in the WWTF (Survey Unit #B1-09100AF) for replicate measurement analysis. The complete ISOCS gamma spectroscopy reports for the replicate measurements are presented in Attachment 6. All duplicate ISOCS measurements met the required acceptance criteria. The completed Duplicate Sample Assessment Forms are included in Attachment 4 of this Release Record.

Two ISOCS detectors were utilized for performing FSS measurements of the WWTF:

detectors 6279 and 5452. There were no QC discontinuities associated with detector 6279. However, due to inclement weather, detector 5452 did exhibit some resolution anomalies likely due to noise associated with vibrations, humidity and wet conditions (rain followed by inversions).

These conditions existed principally on the low end of the spectrum (40-200 keV) resulting in the 86.5 keV Eu-155 energy peak QC data point appearing several keV lower in the spectrum (83.8 keV) while the 1274.5 keV Eu-155 peak was within tolerance. This was evident on the morning source check (8/15/18 at 10:16 AM) with peak energy of 83.76 keV. The Full Width-Half Maximum (FWHM) was acceptable and other principle peaks during operation were found acceptable based on peak location, energy and FWHM values. Identification of the cause (humidity and vibration noise) as well as identification of principle peaks during operation (Cs-137) allowed for the continued operation of the system with the lower energy (86.5 keV Eu-155) out of tolerance. As the weather improved and the inversion lifted, the system noise became less and the Post QC was within tolerance. The collected data was deemed acceptable following inspection of all the spectrums collected.

On 8/17/18 the same conditions occurred during the afternoon Post QC check with the exception that there was no inversion. The conditions were primarily caused by humidity and noise induced by vibration and equipment electrical operated hydraulic motors nearby. The 86.5 keV Eu-155 peak was out of tolerance (83.8 keV). This is approximately 9 channels from the energy peak and about 3 channels out of the tolerance

(~0.75 keV) bounds. Examination of the data indicated the principle peaks of interest were well within tolerance based on peak location, energy and FWHM values. The collected spectrum data after examination was found acceptable.

It is important to note that the QC checks are intended as markers for additional evaluation of the spectrum, as necessary. Careful inspection of the collected data was conducted and the results determined to be acceptable based on both the examination of

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FSS RELEASE RECORD WASTE WATER TREATMENT FACILITY SURVEY UNIT 09100 the individual spectrums, the location of the principle peaks and the identified peaks and tolerances invoked by the Genie2000 software.

9. INVESTIGATIONS AND RESULTS No investigations were conducted in the WWTF.

10. REMEDIATION AND RESULTS Remediation was required prior to performance of FSS. In the case of the WWTF, remediation primarily consisted of system removal and the removal of internal structural surfaces above and below the 588 foot elevation. Following remediation, FSS was conducted successfully and met all acceptance criteria for release of the survey units.

Chapter 4 of the ZSRP LTP states that remediation beyond that required to meet the release criteria is unnecessary and that the remaining residual radioactivity in structures was ALARA.

11. CHANGES FROM THE FINAL STATUS SURVEY PLAN In accordance with the LTP, compliance with the unrestricted release criteria is demonstrated though a series of static measurements taken with an ISOCS. LTP section 5.5.2.2, Table 5-19 lists the WWTF as a Class 1 basement structure survey unit with a total surface area of 1,124 m2. The FSS design specified to demonstrate compliance required a minimum of seventy-one (71) static ISOCS measurements. However, only seventy (70) measurements were collected due to an interior wall being removed during demolition which resulted in the elimination of five (5) sample locations as well as the addition of four (4) measurements due to a decreased FOV. 100% areal coverage of the WWTF surfaces was maintained.

There were no addendums to the FSS plan, however, there were changes to the ISOCS survey plans as noted earlier in this Release Record. Those changes were required due to constraints on placement of ISOCS detectors that were not obvious when the FSS plan was first written. The changes in ISOCS measurement locations were made to ensure 100% areal coverage of the survey units.

12. DATA QUALITY ASSESSMENT (DQA)

The DQO sample design and data were reviewed in accordance with ZionSolutions procedure ZS-LT-300-001-004, Final Status Survey Data Assessment (Reference 12) for completeness and consistency. Documentation was complete and legible. Surveys and the collection of measurements were consistent with the DQOs and were sufficient to

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FSS RELEASE RECORD WASTE WATER TREATMENT FACILITY SURVEY UNIT 09100 ensure that the survey unit was properly designated as Class 1. The survey design had adequate power as indicated by the Retrospective Power Curve (see Attachment 5).

The analytical results of all ISOCS measurements were less than a SOF of one. Although MARSSIM states that the Sign Test need not be performed in the instance that no measurements surpass the DCGL, the test was conducted to demonstrate coherence to the statistical principles of the DQO process. The Sign Test (Attachment 3) 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 preliminary data review consisted of calculating basic statistical quantities (e.g.,

mean, median, standard deviation). All data was considered valid including negative values, zeros, values reported below the MDC, and values with uncertainties that exceeded two standard deviations. The mean and median values for each ROC were well below the respective Operational DCGLs. Also, the retrospective power curve shows that a sufficient number of samples were collected to achieve the desired power. Therefore, the survey unit meets the unrestricted release criteria with adequate power as required by the DQOs.

The data for Co-60 and Cs-137 is represented graphically through a frequency plot and a quantile plot. All graphical representations are provided in Attachment 5.

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

14. COMPLIANCE EQUATION There are four distinct source terms for the end-state at Zion: backfilled basements, soil, buried piping and groundwater. Demonstrating compliance with the dose criterion requires the summation of dose from the four source terms (see Equation 6-11 from LTP Chapter 6, section 6-17).

The final compliance dose will be calculated using Equation 6-11 after FSS has been completed in all survey units. The results of the FSS performed for each FSS unit will be reviewed to determine the maximum dose from each of the four source terms (e.g.,

basement, soil, buried pipe and existing groundwater if applicable) using the mean Base Case SOF of FSS systematic results plus the dose from any identified elevated areas. The compliance dose must be less than 25 mrem/yr. The dose contribution from each ROC is accounted for using the Base Case SOF (BcSOF) to ensure that the total dose from all ROC does not exceed the dose criterion.

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FSS RELEASE RECORD WASTE WATER TREATMENT FACILITY SURVEY UNIT 09100 The term for each Basement includes the dose contributions from wall and floor surfaces within the Basement, the dose contribution from embedded pipe within the Basement, the dose contribution from penetrations within the Basement and the dose contribution from concrete fill in the Basement when clean concrete debris was used as fill. Each (structural surfaces, embedded pipe and penetrations) are surveyed separately during FSS. The dose from clean concrete fill is predetermined in accordance with LTP Chapter 5, Table 5-16, which is conservatively based on a maximum allowable MDC of 5,000 dpm/100cm2. The dose from fill assigned to the WWTF is 6.40 mrem/yr, which equates to a SOF of 0.2560.

The Base Case DCGL for the WWTF accounts for the activity in the structural surface. In accordance with LTP Chapter 6, Table 6-23, no additional adjustments need to occur to the WWTF mean BcSOF to account for the contribution of residual radioactivity from basements/structures that cannot, on their own, support a water supply well but were hydraulically connected to the WWTF. The mean BcSOF for the WWTF is 0.0134, which equates to a dose 0.3352 mrem/yr. The mean BcSOF was then used in the following equation to calculate BcSOFBASEMENT for the WWTF.

Equation 4

= + + +

where:

BcSOFBASEMENT = BcSOF (mean of FSS systematic results plus the dose from any identified elevated areas) for backfilled Basements BcSOFB = BcSOF for structural survey unit(s) within the Basement (mean of FSS systematic results plus the dose from any identified elevated areas)

BcSOFEP = BcSOF for embedded pipe survey unit(s) within the Basement (mean of FSS systematic results plus the dose from any identified elevated areas)

BcSOFPN = BcSOF for penetration survey unit(s) within the Basement (mean of FSS systematic results plus the dose from any identified elevated areas)

BcSOFCF = BcSOF for clean concrete fill (if applicable) based on maximum MDC during Unrestricted Release Survey (URS)

There are no penetrations or embedded pipe associated with the WWTF basement.

Consequently, the dose contribution from both (variables BcSOFEP and BcSOFPN) are zero.

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FSS RELEASE RECORD WASTE WATER TREATMENT FACILITY SURVEY UNIT 09100 The BcSOFBASEMENT value for the WWTF is then derived as follows; Equation 5

= 0.0134 + 0.0000 + 0.00000 + 0.2560 = 0.2694 The BcSOFBASEMENT for the WWTF basement is 0.2694. This SOF equates to a dose of 6.7350 mrem/yr TEDE to an AMCG from residual radioactivity in the WWTF basement.

15. CONCLUSION Survey Unit #B1-09100AF has met the DQOs of the FSS plan. The ALARA criteria as specified in Chapter 4 of the LTP were achieved. The EMC is not applicable to structural surfaces and remediation was successfully implemented.

All identified ROC were used for statistical testing to determine the adequacy of the survey unit for FSS. Evaluation of the data shows that none of the ROC concentration values exceed the Operational DCGL or any investigational levels; therefore, in accordance with the LTP Section 5.10, the survey unit meets the release criterion.

The sample data passed the Sign Test. The null hypothesis was rejected. The Retrospective Power Curve showed that adequate power was achieved. The survey unit is properly classified as Class 1.

The dose contribution from structural surfaces in Survey Unit #B1-09100AF, WWTF Basement, is 0.3352 mrem/yr TEDE, based on the average concentration of the ROC in samples used for non-parametric statistical sampling. The dose from embedded pipe and penetrations in the WWTF is zero and the dose from clean fill is 6.40 mrem/yr. The total dose attributed to the Crib House/Forebay as a summation of all dose components is 6.7350 mrem/yr.

Survey Unit #B1-09100AF, Crib House/Forebay Basement is acceptable for unrestricted release.

16. REFERENCES

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

2. Zion Station Restoration Project License Termination Plan

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)

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FSS RELEASE RECORD WASTE WATER TREATMENT FACILITY SURVEY UNIT 09100

5. ZionSolutions TSD 17-004, Operational Derived Concentration Guideline Levels for FSS

6. ZionSolutions Technical Support Document (TSD)14-014, End State Surface Areas, Volumes, and Source Terms of Ancillary Buildings

7. Zion Station Historical Site Assessment (HSA)

8. ZionSolutions TSD 11-001, Potential Radionuclides of Concern during the Decommissioning of Zion Station

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

10. ZionSolutions TSD 14-022, Use of In-Situ Gamma Spectroscopy for Source Term Survey of End State Structures

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

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

17. ATTACHMENTS Attachment 1 - Additional Figures and Maps Attachment 2 - ISOCS Geometry Attachment 3 - Sign Test Attachment 4 - QC Measurement Assessments Attachment 5- Graphical Presentations Attachment 6 - Eberline Report Attachment 7 - ISOCS Analytical Reports

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FSS RELEASE RECORD WASTE WATER TREATMENT FACILITY SURVEY UNIT 09100 ATTACHMENT 1 ADDITIONAL FIGURES AND MAPS

[37]

FSS RELEASE RECORD WASTE WATER TREATMENT FACILITY SURVEY UNIT 09100 Figure 1 - Waste Water Treatment Facility Top View from Drawing B-1024

[38]

FSS RELEASE RECORD WASTE WATER TREATMENT FACILITY SURVEY UNIT 09100 Figure 2 - Waste Water Treatment Facility ISOCS Measurement & Core Locations

[39]

FSS RELEASE RECORD WASTE WATER TREATMENT FACILITY SURVEY UNIT 09100 ATTACHMENT 2 ISOCS Geometry

[40]

FSS RELEASE RECORD WASTE WATER TREATMENT FACILITY SURVEY UNIT 09100 Waste Water Treatment Facility Geometries As per TSD 14-022 Revision 1, a contamination depth of 0.5 inches (1.27 cm) was suggested for the Waste Water Treatment Facility (WWTF) with all the activity associated within the one-half inch layer. For the floors and walls of the WWTF, the Geometry Composer Circular Plane Template was used for the geometry. A source to detector distance of 3.0 meters was selected.

While several geometries were created where the source to detector distance was varied from 1 to 3 meters, only the 3 meter distance was necessary. A 90 degree collimator was used resulting in a six meter diameter field of view (FOV) that comprised 28.3 m2. Measurements that were conducted using the 3 meter source to detector geometry were indicative of minimal surficial contamination.

There are several (3) sumps located at the WWTF of varying dimensions. In addition, the Clarifier, Flocculator Tank and Sludge Holding Tank exhibited geometries that were not well represented by the 3 meter source to detector geometry. To this end, separate geometries were designed for each of these using the Geometry Composer Room template to address the anomalies and best represent the geometric dimensions. The Room geometry assumes surface contamination.

Sump 1 (Location 67)

Sump 1 is located in the NE corner of the WWTF Filter Area. It is 36.25 inches wide, 60 inches long and 55.25 inches deep resulting in an area of 8.26 m2. The Room Geometry utilizes a 180 degree FOV (collimator removed) and the measurement location is at the top center of the room. That is at the lip of the sump (floor surrounding the sump). Residual contamination was assumed to comprise 10 percent of each wall and 60 percent of the floor.

Sump 2 (Location 68)

Sump 2 is located central and slightly south of the A wall in the Equalization Tank room. It is 120 inches wide, 48 inches long and 24 inches deep. Due to the length of the sump, it is divided into two Room Geometry measurement locations 60 inches by 48 inches by 24 inches deep.

Each location results in an area of 4.27 m2. The measurement location utilizes a 180 degree FOV is at the lip of the sump (floor surrounding the sump) at the top center of the room.

Residual contamination was assumed to comprise 10 percent of each wall and 60 percent of the floor.

Sump 3 (Locations 74, 75 and 69)

Sump 3 is the Sludge Holding Tank Area located on the NE end of the WWTF. This Room Geometry is divided into two measurement locations 58 inches wide, 90 inches long and 53 inches deep. While the south, north and west wall slopes to the sump region (location 69), the geometry was treated as a square box resulting in conservative values for the three walls. The East wall is perpendicular. There is no real sump at the bottom, only a region the inclined walls

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FSS RELEASE RECORD WASTE WATER TREATMENT FACILITY SURVEY UNIT 09100 slope towards. Each location results in a total area of 10.41 m2. The bottom was assumed square resulting in a slightly non-conservative area estimate that is offset by the assumption of a box design whereas three of the side walls are sloping and the source to detector distance is less than the values used. A third measurement that was not required was acquired over the sump using the same geometry. In all cases, the geometry included the 180 degree FOV (collimator removed) and was centered over each 58 by 90 inch region. The sump 3 measurement (location 69) was centered over the sump. As before, the measurement location is at the lip of the Sludge Holding Tank (top elevation floor). Residual contamination was assumed to comprise 10 percent of each wall and 60 percent of the floor.

Flocculator Tank Sump (Locations 72 and 73)

The Flocculator Tank had been two separate compartments but during renovation, the central wall was removed as was the north wall. The Flocculator Tank was divided into two regions 76 inches wide, 103.5 inches long and 56 inches deep. Location 72 resulted in just two walls remaining. The Room Geometry accounted for this location by assuming that 50 percent of the residual contamination was present on each of the two walls. As before, the source to detector distance assumed the depth of the Flocculator tank (56 inches). The 180 degree FOV was used (collimator removed) and the measurement acquired at the lip of the Flocculator Tank (floor surrounding the tank). An area of 5.42 m2 was used. The measurement location was centered over the region.

The second compartment of the Flocculator Tank (Location 73) uses the same dimensions as Location 72 above except this compartment consist of 3 walls and results in an area of 9.23 m2.

Location 73 utilizes the same source to detector distance, FOV and measurement centering as Location 72. Residual contamination was assumed to reside over three walls and the floor at a 0.25 concentration.

Clarifier Sump (Location 70 and 71)

The Clarifier Sumps) consist of two identical locations that are 96 inches wide, 90 inches long and 60 inches deep. These locations consist of sloped walls on the east and west sides and vertical walls on the north and south sides. The Room Geometry was used for these locations.

Assuming a rectangular box, the total surface area was calculated to be 19.97 m2. Adjustments were made to accommodate the area reduction due to sloping sides resulting in a surface area of 15.33 m2. However, the physical geometry conservatively assumed the sides were perpendicular. The 180 degree FOV was used with the detector located at the center of the rectangular area and at the lip of the Clarifier.

[42]

FSS RELEASE RECORD WASTE WATER TREATMENT FACILITY SURVEY UNIT 09100 Waste Water Treatment Facility 3 WWTF1.27CM

[43]

FSS RELEASE RECORD WASTE WATER TREATMENT FACILITY SURVEY UNIT 09100 Waste Water Treatment Facility 3 WWTF1.27CM (continued)

[44]

FSS RELEASE RECORD WASTE WATER TREATMENT FACILITY SURVEY UNIT 09100 Waste Water Treatment Facility 3M 90D CP WWTF1.27CM (continued)

[45]

FSS RELEASE RECORD WASTE WATER TREATMENT FACILITY SURVEY UNIT 09100 Waste Water Treatment Facility 3M 90D CP WWTF1.27CM (continued)

[46]

FSS RELEASE RECORD WASTE WATER TREATMENT FACILITY SURVEY UNIT 09100 Waste Water Treatment Facility Sump 1

[47]

FSS RELEASE RECORD WASTE WATER TREATMENT FACILITY SURVEY UNIT 09100 Waste Water Treatment Facility Sump 1 (continued)

[48]

FSS RELEASE RECORD WASTE WATER TREATMENT FACILITY SURVEY UNIT 09100 Waste Water Treatment Facility Sump 2

[49]

FSS RELEASE RECORD WASTE WATER TREATMENT FACILITY SURVEY UNIT 09100 Waste Water Treatment Facility Sump 2 (continued)

[50]

FSS RELEASE RECORD WASTE WATER TREATMENT FACILITY SURVEY UNIT 09100 Waste Water Treatment Facility Sump 3

[51]

FSS RELEASE RECORD WASTE WATER TREATMENT FACILITY SURVEY UNIT 09100 Waste Water Treatment Facility Sump 3 (continued)

[52]

FSS RELEASE RECORD WASTE WATER TREATMENT FACILITY SURVEY UNIT 09100 Waste Water Treatment Facility Flocculator Tank 73

[53]

FSS RELEASE RECORD WASTE WATER TREATMENT FACILITY SURVEY UNIT 09100 Waste Water Treatment Facility Flocculator Tank 73 (continued)

[54]

FSS RELEASE RECORD WASTE WATER TREATMENT FACILITY SURVEY UNIT 09100 Waste Water Treatment Facility Flocculator Tank 73 (continued)

[55]

FSS RELEASE RECORD WASTE WATER TREATMENT FACILITY SURVEY UNIT 09100 Waste Water Treatment Facility Flocculator Tank 72

[56]

FSS RELEASE RECORD WASTE WATER TREATMENT FACILITY SURVEY UNIT 09100 Waste Water Treatment Facility Flocculator Tank 72 (continued)

[57]

FSS RELEASE RECORD WASTE WATER TREATMENT FACILITY SURVEY UNIT 09100 Waste Water Treatment Facility Flocculator Tank 72 (continued)

[58]

FSS RELEASE RECORD WASTE WATER TREATMENT FACILITY SURVEY UNIT 09100 Waste Water Treatment Facility Clarifier Tank

[59]

FSS RELEASE RECORD WASTE WATER TREATMENT FACILITY SURVEY UNIT 09100 Waste Water Treatment Facility Clarifier Tank (continued)

[60]

FSS RELEASE RECORD WASTE WATER TREATMENT FACILITY SURVEY UNIT 09100 Waste Water Treatment Facility Clarifier Tank (continued)

[61]

FSS RELEASE RECORD WASTE WATER TREATMENT FACILITY SURVEY UNIT 09100 ATTACHMENT 3 SIGN TEST

[62]

FSS RELEASE RECORD WASTE WATER TREATMENT FACILITY SURVEY UNIT 09100 Sign Test Waste Water Treatment Facility Survey Area 09100 Description Out Buildings Survey Unit B1-09100A-F Description WWTF Classification 1 Type I Error 0.05 # of Measurements 70 SOF

1. 1-WS Sign (WS) 1 0.0414 0.96 +1 2 0.0642 0.94 +1 3 0.0071 0.99 +1 4 0.0663 0.93 +1 5 0.0656 0.93 +1 6 0.0703 0.93 +1 7 0.0647 0.94 +1 8 0.0796 0.92 +1 9 0.0478 0.95 +1 10 0.0093 0.99 +1 11 0.0608 0.94 +1 12 0.0619 0.94 +1 13 0.2361 0.76 +1 14 0.0988 0.90 +1 15 0.0938 0.91 +1 16 0.0591 0.94 +1 17 0.0543 0.95 +1 18 0.0547 0.95 +1 19 0.1139 0.89 +1 20 0.1429 0.86 +1 21 0.1145 0.89 +1 22 0.0826 0.92 +1 23 0.0771 0.92 +1 24 0.0632 0.94 +1 25 0.0482 0.95 +1 26 0.0357 0.96 +1 27 0.0741 0.93 +1 28 0.1019 0.90 +1 29 0.0492 0.95 +1 30 0.1222 0.88 +1 31 0.0732 0.93 +1 32 0.0680 0.93 +1 33 0.1092 0.89 +1 34 0.0611 0.94 +1

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FSS RELEASE RECORD WASTE WATER TREATMENT FACILITY SURVEY UNIT 09100 Sign Test Waste Water Treatment System (continued)

SOF

1. 1-WS Sign (WS) 35 0.0395 0.96 +1 36 0.0763 0.92 +1 37 0.1515 0.85 +1 38 0.0790 0.92 +1 39 0.0482 0.95 +1 40 0.0838 0.92 +1 41 0.1348 0.87 +1 42 0.0920 0.91 +1 43 0.0671 0.93 +1 44 0.0997 0.90 +1 45 0.0774 0.92 +1 51 0.1145 0.89 +1 52 0.0643 0.94 +1 53 0.0230 0.98 +1 54 0.0775 0.92 +1 55 0.1000 0.90 +1 56 0.0226 0.98 +1 57 0.0377 0.96 +1 58 0.1001 0.90 +1 59 0.1055 0.89 +1 60 0.0417 0.96 +1 61 0.0430 0.96 +1 62 0.1074 0.89 +1 63 0.0545 0.95 +1 64 0.0453 0.95 +1 65 0.0506 0.95 +1 66 0.0564 0.94 +1 67 0.0392 0.96 +1 68 0.0330 0.97 +1 69 0.0327 0.97 +1 70 0.0252 0.97 +1 71 0.0233 0.98 +1 72 0.1007 0.90 +1 73 0.0152 0.98 +1 74 0.0166 0.98 +1 75 0.0331 0.97 +1 Number of Positive Differences (S+) = 70 Critical Value = 40 Survey Unit Meets the Acceptance Criteria

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FSS RELEASE RECORD WASTE WATER TREATMENT FACILITY SURVEY UNIT 09100 ATTACHMENT 4 QC MEASUREMENT ASSESSMENTS

[65]

FSS RELEASE RECORD WASTE WATER TREATMENT FACILITY SURVEY UNIT 09100 Replicate Measurement Assessment Survey Unit # 09100 Survey Unit Name WWTF Sample Plan # B1-09100A-F Sample

Description:

Comparison of systematic and QC ISOCS measurements of concrete floor at location #014.

STANDARD COMPARISON ROC Activity Standard Resolution Agreement Activity Standard Compariso Acceptable Value Error Range Value Error n Ratio (Y/N)

Cs-137 2.57E+04 1.00E+00 25,700 0.85-1.18 3.56E+03 1.00E+00 7.22 N K-40 7.60E+05 2.13E+05 4 0.5-2.0 8.85E+05 2.20E+05 0.86 Y Comments/Corrective Actions: (1)-For Cs-137, Table is provided to show acceptance criteria comparison sample had a negative value and the used to assess split samples.

standard error was not reported, therefore the value of 1 was used for the comparison sample activity and standard error. The Cs-137 activity for both the standard and comparison samples were less than the respective MDC's (2.76E+04 pCi/m2 and 2.52E+04 pCi/m2 respectively). When K-40 was used to compare the standard and comparison samples, they indicated an acceptable level of agreement between the two samples.

Performed By: Date 8/28/2018 Reviewed by: Date : 8/28/2018 R. Massengill R. Decker

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FSS RELEASE RECORD WASTE WATER TREATMENT FACILITY SURVEY UNIT 09100 Replicate Measurement Assessment Survey Unit # 09100 Survey Unit Name WWTF Sample Plan # B1-09100A-F Sample

Description:

Sample

Description:

Comparison of systematic and QC ISOCS measurements of concrete floor at location # 009.

STANDARD COMPARISON ROC Activity Standard Resolution Agreement Activity Standard Compariso Acceptable Value Error Range Value Error n Ratio (Y/N)

Cs-137 3.15E+03 1.00E+00 3,150 0.85-1.18 2.14E+04 1.00E+00 0.15 N K-40 1.22E+06 2.36E+05 5 0.5-2.0 1.01E+06 2.48E+05 1.21 Y Comments/Corrective Actions: (1)-For Cs-137, the Table is provided to show acceptance criteria standard error was not reported, therefore the value used to assess split samples.

of 1 was used for standard error. The Cs-137 activity for both the standard and comparison samples were less than the respective MDC's (2.4E+04 pCi/m2 and 2.14E+04 pCi/m2 respectively). When K-40 was used to compare the standard and comparison samples, they indicated an acceptable level of agreement between the two samples.

Performed By: Date 8/28/2018 Reviewed by: Date : 8/28/2018 R. Massengill R. Decker

[67]

FSS RELEASE RECORD WASTE WATER TREATMENT FACILITY SURVEY UNIT 09100 Replicate Measurement Assessment Survey Unit # 09100 Survey Unit Name WWTF Sample Plan # B1-09100A-F Sample

Description:

Comparison of systematic and QC ISOCS measurements of concrete wall at location # 027.

STANDARD COMPARISON ROC Activity Standard Resolution Agreement Activity Standard Compariso Acceptable Value Error Range Value Error n Ratio (Y/N)

Cs-137 2.57E+04 1.00E+00 3,150 0.85-1.18 1.00E+00 1.00E+00 25,700 N K-40 1.06E+06 2.34E+05 5 0.5-2.0 1.11E+06 2.48E+05 0.95 Y Comments/Corrective Actions: (1)-For Cs-137, Table is provided to show acceptance criteria comparison sample had a negative value and the used to assess split samples.

standard error was not reported, therefore the value of 1 was used for the comparison sample activity and standard error. The Cs-137 activity for both the standard and comparison samples were less than the respective MDC's (2.76E+04 pCi/m2 and 2.52E+04 pCi/m2 respectively). When K-40 was used to compare the standard and comparison samples, they indicated an acceptable level of agreement between the two samples.

Performed By: Date 8/28/2018 Reviewed by: Date : 8/28/2018 R. Massengill R. Decker

[68]

FSS RELEASE RECORD WASTE WATER TREATMENT FACILITY SURVEY UNIT 09100 Replicate Measurement Assessment Survey Unit # 09100 Survey Unit Name WWTF Sample Plan # B1-09100A-F Sample

Description:

Comparison of systematic and QC ISOCS measurements of concrete wall at location # 053.

STANDARD COMPARISON ROC Activity Standard Resolution Agreement Activity Standard Compariso Acceptable Value Error Range Value Error n Ratio (Y/N)

Cs-137 6.59E+03 1.00E+00 6,590 0.85-1.18 3.34E+04 1.29E+04 0.20 N K-40 7.14E+05 2.03E+05 4 0.5-2.0 8.35E+05 2.04E+05 0.86 Y Comments/Corrective Actions: (1)-For Cs-137, the Table is provided to show acceptance criteria standard error was not reported, therefore the value used to assess split samples.

of 1 was used for the comparison sample and standard error. The Cs-137 activity for the standard sample was less than the MDC (3.16E+04 pCi/m2).

When K-40 was used to compare the standard and comparison samples, they indicated an acceptable level of agreement between the two samples.

Performed By: Date 8/28/2018 Reviewed by: Date : 8/28/2018 R Massengill R. Decker

[69]

FSS RELEASE RECORD WASTE WATER TREATMENT FACILITY SURVEY UNIT 09100 ATTACHMENT 5 GRAPHICAL PRESENTATIONS

[70]

FSS RELEASE RECORD WASTE WATER TREATMENT FACILITY SURVEY UNIT 09100 Quantile Plot for Co-60 Survey Unit: B1-09100AF

Description:

Waste Water Treatment Facility Mean: 7.06E+03 pCi/m2 Quantile Plot For Co-60 6.00E+04 5.00E+04 Concentration (pCi/m2) 4.00E+04 3.00E+04 2.00E+04 1.00E+04 0.00E+00 0% 20% 40% 60% 80% 100%

Percentage

[71]

FSS RELEASE RECORD WASTE WATER TREATMENT FACILITY SURVEY UNIT 09100 Quantile Plot for Cs-137 Survey Unit: B1-09100AF

Description:

Waste Water Treatment Facility Mean: 1.12E+04 pCi/m2 Quantile Plot For Cs-137 4.00E+04 3.50E+04 Concentration (pCi\m2) 3.00E+04 2.50E+04 2.00E+04 1.50E+04 1.00E+04 5.00E+03 0.00E+00 0% 20% 40% 60% 80% 100%

Percentage

[72]

FSS RELEASE RECORD WASTE WATER TREATMENT FACILITY SURVEY UNIT 09100 Histogram for Co-60 Survey Unit: B1-09100A

Description:

Waste Water Treatment Facility Mean: 7.06E+03 pCi/m2 Median: 5.61E+03 pCi/m2 ST Dev.: 8.38E+03 Skew: 3.03E+00 Frequency Plot For Co-60 45%

40%

35%

30%

Frequency 25%

20%

15%

10%

5%

0%

1.00E+00 3.00E+00 5.00E+00 7.00E+00 9.00E+00 Upper End Value (pCi/m2)

Upper Value Observation Observation %

Frequency 4.99E+03 30 43%

9.98E+03 26 37%

1.50E+04 8 11%

2.00E+04 3 4%

2.50E+04 1 1%

2.99E+04 0 0%

3.49E+04 0 0%

3.99E+04 0 0%

4.49E+04 1 1%

4.99E+04 1 1%

TOTAL 70 100%

[73]

FSS RELEASE RECORD WASTE WATER TREATMENT FACILITY SURVEY UNIT 09100 Histogram for Cs-137 Survey Unit: B1-09100A

Description:

Waste Water Treatment Facility Mean: 3.15E+06 pCi/m2 Median: 8.10E+05 pCi/m2 ST Dev.: 6.86E+06 Skew: 5.16E+00 Frequency Plot For Cs-137 25%

20%

Frequency 15%

10%

5%

0%

1.00E+00 3.00E+00 5.00E+00 7.00E+00 9.00E+00 1.10E+01 Upper End Value (pCi/m2)

Upper Value Observation Observation %

Frequency 3.43E+03 15 21%

6.86E+03 8 11%

1.03E+04 8 11%

1.37E+04 11 16%

1.72E+04 14 20%

2.06E+04 6 9%

2.40E+04 2 3%

2.74E+04 3 4%

3.09E+04 0 0%

3.09E+04 2 3%

TOTAL 70 100%

[74]

FSS RELEASE RECORD WASTE WATER TREATMENT FACILITY SURVEY UNIT 09100 Retrospective Power Curve for Survey Unit #B1-09100AF

[75]

FSS RELEASE RECORD WASTE WATER TREATMENT FACILITY SURVEY UNIT 09100 ATTACHMENT 6 EBERLINE REPORT

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FSS RELEASE RECORD WASTE WATER TREATMENT FACILITY SURVEY UNIT 09100 ATTACHMENT 7 ISOCS ANALYTICAL REPORTS

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