ML18292A646
| ML18292A646 | |
| Person / Time | |
|---|---|
| Site: | Erwin |
| Issue date: | 09/30/2018 |
| From: | Wood Environment & Infrastructure Solutions |
| To: | BWXT Nuclear Fuel Services |
| Shared Package | |
| ML18292A657 | List: |
| References | |
| 21G-18-0107, ACF-18-0207, CAC L33421, GOV-01-55-06 | |
| Download: ML18292A646 (52) | |
Text
I -
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ADDENDUM TO THE FINAL STATUS SURVEY REPORT FOR SURVEY UNITS 4,6~7,12,16,17,18 NUCLEAR FUEL SERVICES NORTH SITE Erwin, Tennessee SURVEY UNITS 6 AND 7 SURFACE SOIL CHARACTERIZATION PREPARED FOR:
BWXT NUCLEAR FUEL SERVICES, INC.
PREPARED. BY:
WOOD ENVIRONMENT & INFRASTRUCTURE SOLUTIONS, INC.
WOOD PROJECT No. 910217003 REVISION 1 SEPTEMBER 2018 WORK PERFORMED UNDER PURCHASE ORDER NO. SC04004-1 wood.
ADDENDUM TO THE FINAL STATUS SURVEY REPORT FOR SURVEY UNITS 4, 6, 7, 12, 16, 17, 18 NFS North Site-SURVEY UNITS 6 AND 7 SURFACE SOIL CHARACTERIZATION NUCLEAR FUEL SERVICES NORTH SITE Erwin, Tennessee US NRC SNM license Number 124 Docket Number 70-143 Prepared for:
BWXT Nuclear Fuel Services, Inc.
1205 Banner Hill Road
- Erwin, TN 37650 Prepared by:
wood.
2275 Logos Court, Suite A Grand Junction, CO 81505
- Contract No. SC4004-1 Project No. 910217003 Revision 1 September 2018 wood.
SU6 and SU? Surface Soil Characterization Revision 1 Page i FSS Report Addendum September 2018
Table of Contents 1
INTRODUCTION............................................................................................................................................... l 1.1 Project Objective................................................................................................................................... 1 2
RESULTS.............................................................................................................................................................. 3 2.1 Survey Uriit 6.......................................................................................................................,.................... 3 2.1.1 In-Situ Static Gamma Spectroscopy Measurement............................................................ 3 2.1.2 Surface Soil Samples....................................................................................................................... 8 2.1.3 Gamma Scanning Results........................................................................................................... 13 2.2 Survey Unit 7...... :.................................................... :................................................... :........................ 15 2.2.l In-Situ Static Gamma Spectroscopy Measurement......................................................... 15 2.2.2 Surface Soil Samples.................................................................................................................... 21 2.2.3 Gamma Scanning Results........................................................................................................... 24 2.3 Phase 2 Investigation................................................................................... :.................................... 27 2.3.1 Systematic Sampling Design..................................................................................................... 28 2.3.2 Area A........................................................................................................................... :.................... 28 2.3.3 Area B................................................................................................................................................ 33 3
QUALITY CONTROL.................................................... :................................................................................ 39 3.1 ScanPLot:5M............................................................................................................................................. 39 3.2 Laboratory Analysis........................................................................................................................... 41 4
CONCLUSION................................................................................................................................................ 42 5
ACRONYMS.................................................................................................................................................... 43 6
REFERENCES....................................*........................................................................................... :.................. 44 APPENDIX A................................................................................................................................................................ 1 NFS North Site-SU6 and SU7 Surface Soil Characterization Revision 1 wood.
Page ii FSS Report Addendum September 2018
Figure 1.
Figure 2.
Figure 3.
Figure 4.
Figure 5.
Figure 6.
Figure 7.
Figure 8.
Figure 9.
Figure 10.
Figure 11.
Figure 12.
Figure 13.
Figure 14.
Figure 15.
Figure 16.
Figure 17.
Figure 18.
Figure 19.
Figure 20.
Figure 21.
Figure 22.
Figure 23.
Figure 24.
Figure 25.
Figure 26.
Figure 27.
Figure 28.
Figure 29.
Figure 30.
Figure 31.
Figure 32.
Table 1.
Table 2.
Table 3.
Table 4.
Tal:lle5.
Table 6.
Table 7.
Table 8.
Table 9.
Table 10.
Table 11.
Table 12.
Table 13.
Table 14.
Table 15.
Table of Figures SU6 Sample Locations............................................................................................................... 3 SU6 In-Situ Descriptive Statistics K-40...................................................................................... 4 SU6 In-Situ Descriptive Statistics Am-241................................................................................. 5 SU6 In-Situ Descriptive Statistics U-235.................................................................................... 5 SU6 In-Situ Descriptive Statistics Th-232.................................................................................. 6 SU6 Soil Sample Statistics Summary Am-241........................................................................... 9 SU6 Soil Sample Statistics Summary U-235.............................................................................. 9 SU6 Soil Sample Statistics Summary Th-232.......................................................................... 10 SU6 Gross Gamma Map (cps)................................................................................................. 13 SU6Am-241 Gamma Map (cps).................................................................................,............ 14 SU6 U-235 Gamma Map (cps)................................................................................................. 14 SU6 Th-232 Gamma Map (cps)....... :....................................................................................... 15 SU? Sample Locations............................................................................................................. 16 SU? In-Situ Descriptive Statistics K-40.................................................................................... 17 SU? In-Situ Descriptive Statistics Am-241............................................................................... 18 SU? In-Situ Descriptive Statistics U-235.................................................................................. 18 SU7 In-Situ Descriptive Statistics Th-232...........,.................................................................... 19 Su'7 Soil Sample Statistics Summary Am-241......................................................................... 21 SU7 Soil Sample Statistics Summary U-235............................................................................ 22 SU7 Soil Sample Statistics Summary Th-232.......................................................................... 22 SU7 Gross Gamma Map (cps)................................................................................................. 25 SU7 Gross Am-241 Gamma Map (cps)................................................................................... 25 SU7 Gross U-235 Gamma Map (cps)*************************************************.************************************* 26 SU7 Net Th-232 Gamma Map (cps)......................................................................................... 26 Areas A & B............................................................................................................................. 27 Area Sampling Plan................................................................................................................. 28 Area A Interpolation................................................................................................................. 30 Area A SOF Comparison......................................................................................................... 32 Area B Interpolation................................................................................................................. 35 Area B SOF Comparison......................................................................................................... 37 SU6 K-40 Gamma Map (cps)................................................................................................... 40 SU7 K-40 Gamma Map (cps)........................................................................................ :.......... 40 Table of Tables North Site Surface Soil DCGLs.................................................................................................. 2 SU6 In-Situ Corehole Gamma Spectrometry Measurements..................................................... 7 SU6 Soil Sample Results......................................................................................................... 11 SU7 In-Situ Corehole Gamma Spectrometry Measurements..................................,................ 20 SU7 Soil Sample Results......................................................................................................... 23 Area A Soil Sample Results..................................................................................................... 29 Area A Spatially Weighted Am-241 Values.............................................................................. 31 Area A Spatially Weighted U-235 Values................................................................................. 31 Area A Spatially Weighted Th-232 Values............................................................................... 32 SU7 & Area A SOF Evaluation................................................................................................. 33 Area B Soil Sample Results..................................................................................................... 34 Area B Spatially Weighted Am-241 Values.............................................................................. 36 Area 8 Spatially Weighted U-235 Values................................................................................. 36 Area B Spatially Weighted Th-232 Values............................................................................... 37 SU7 & Area B SOF Evaluation................................................................................................. 38 wood.
NFS North Site-SU6 and SU7 Surface Soil Characterization Revision 1 Page iii FSS Report Addendum September 2018
This page intentionally left blank NFS North Site-SU6 and SU? Surface Soil Characterization Revision 1 wood.
Page ii FSS Report Addendum September 2018
1 INTRODUCTION This report provides a summary of the surface soil investigations performed in Survey Units (SU) 6 and 7 at BWXT Nuclear Fuel Services, Inc. (NFS) North Site by Wood Environment &
Infrastructure Solutions, Inc., (Wood), formerly Aniec Foster Wheeler Environment &
Infrastructure, Inc. (AmecFW), and MACTEC Development Corp. (MACTEC). Survey Units 6 and 7 subsurface soils were previously characterized as part of the Subsurface Soil Characterization and Final Status Survey (FSS) Project. The subsurface soils passed the
- requirements for free release. However, this surface soil survey and investigation were performed to respond to the request for additional information (RAI) process from Nuclear Regulatory Commission (NRC) staff.
1.1 PROJECT OBJECTIVE The NFS North Site Surface Soil Survey Project objective was to execute a radiological survey and investigation focused on the surface soils (top 15 cm) for SU6 and SU7 to augment the previously completed FSS. The detailed survey design is provided in the NFS North Site Surface Soil Survey Project Field Sampling Plan (FSP), NFS-PLN-001 Rev. 1, (AmecFW 2017).
The survey was designed to evaluate the radiological condition of the survey units in a manner that would be comparable to the methodology utilized and data generated under the NFS North Site Subsurface Soil Characterization and Final Status Survey Project. The design included the following measurements for each survey unit.
- 1) In-situ static gamma spectroscopy measurements performed at each of the previously established corehole locations,
- 2) Collection of surface soil samples (250 ml volume sample from each location) from the top 15 cm (6 inches) of the surface at each of the corehole locations,
- 3) Gamma spectroscopy scanning measurements performed across the accessible areas of the survey units, and
- 4) Investigation of locally elevated measurements in SU7.
The survey was performed August/September 2017, with the Phase 2 investigation conducted in January/ February 2018. Results of the survey were compared to the established radioactivity surface soil Derived Concentration Guidance Levels (DCGLs) published in the North Site Decommissioning Plan (DP, NFS 2006) and reproduced in Table 1.
NFS North Site-SU6 and SU7 Surface Soil Characterization Revision 1 wood.
Page 1 FSS Report Addendum September 2018
Table 1.
North Site Surface Soil DCGLs Isotope DCGLw (pCi/g) a Am-241 130 Pu-238 155 Pu-239 140 Pu-240 141 Pu-241 4365 Pu-242 148 Tc-99 414 Th-230 17 Th-232 3.7 U-233/234(bl 642 U-235 74 U-238 306
'\\
(al DCGLw values are published in the NFS North Site DP (NFS 2006)
(bl DCGL is for the sum of U-233 and U-234 NFS North Site-SU6 and SU7 Surface Soil Characterization Revision 1 wood.
Page2 FSS Report Addendum September 2018
2 RESULTS 2.1 SURVEY UNIT 6 2.1.1 In-Situ Static Gamma Spectroscopy Measurement In-situ static measurements were taken at each corehole location (Figure 1) that was established as part of the subsurface characterization of the North Site. The measurements were performed by positioning the ScanPlot5M push cart platform over each of the 60 corehole locations and collecting a stationary, 5-minute, spectral gamma measurement. Gamma spectra were collected using Wood proprietary data collection software.
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C C
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0 D
D a
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0 C
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?ropn<!,tlllt B'V' D7.of.OI I CM ta'O.r.t. A rJ7
,OS J Surveyunne Proj..:t Qt20.07-123&
-*,-e Figure 1.
SU6 Sample Locations NFS North Site-SU6 and SU? Surface Soil Characterization Revision 1 wood.
Page 3 FSS Report Addendum September 2018
Subsequently, the spectra were processed in order to calculate the gross counts in a number of regions of interest (ROI) associated with the isotopes of interest (americium-241 [Am-241].
uranium-235 [U-235]. thorium-232 [Th-232]. radium-226 [Ra-226] and potassium-40 [K-40]). Net photo peak counts were then derived for K-40, Ra-226, and Th-232. The net Th-232 count rates were also converted to soil concentrations in pCi/g for direct comparison with the surface soil DCGL. Ra-226 and K-40 were reported to be able to isolate the gamma signals from the isotopes of interest from the naturally present isotopes.
ProUCL Version 5.1 (EPA 2016) is a statistical software package developed and updated by the EPA. It was used to generate summary statistics and histograms from the field and analytical data.
The generated histograms include summary statistics and display a fitted normal distribution curve as a background, providing a visual indication of the normality of the data or lack thereof.
- Histograms of the data points compared to a normal distribution, and general summary statistics for K-40 and the primary gamma-emitting isotopes of interest are provided in the sequence of figures from Figure 2 to Figure 5. Results of the in-situ static measurements are presented in Table 2.
Net K-40 (cps)
Net K-40 (cps) 40 Number of Values 60 Minimum 71.00 35 Ma>:imum 271.00 30 SD 36.46 Skewness
-3.05 6 25 C:
Kurtosis 9.54 Q) 5-20 0Mean 235.47 Q)
Li:
15 0 Median 246.00
~ Normal Distribution 10 5
1 0 --
1 2
1 1
_._~~-----
0 Less Bins 0 More Bins 80 120 160 200 240 280 cps Figure 2.
SU6 In-Situ Descriptive Statistics K-40 NFS North Site-SU6 and SU? Surface Soil Characterization Revision 1 wood.
Page 4 FSS Report Addendum September 2018
SU 6 Gross Am-241 Gross Am-241 (cps) 35 Number of Values 63 Minimum 123.95 30 Maximum 184.87 SD 11.39 25 Skewness
-3. 10 Kurtosis 11.02 g 20 0Mean 174.14 Cl) :,
D Median 176.68 O"
Lt 15
~ Normal Distribution 10 D Less Bins 5
D More Bins 2
0 -
D 0
134 146 158 171 183 cps Figure 3.
SU6 In-Situ Descriptive Statistics Am-241 SUS Gross U-235 Gross U-235 [cps]
Number of Values 63 28 Minimum 118.37 Maximum 204.25 24 SD 16.44 20 Skewness
-3.21 B'
Kurtosis 11.08
~ 16 0Mean 190.54 O"
Cl) 0Median 195.20 w: 12
~
Normal Distribution 8
4 D Less Bins 2
D More Bins 0 -
D 0
120 137 172 189 cps Figure 4.
SU6 In-Situ Descriptive Statistics U-235 NFS North Site-SU6 and SU? Surface Soil Characterization Revision 1 wood.
Page 5 FSS Report Addendum September 2018
SU6 Net Th-232 Net Th-232b (pCi/g) 30 27 24 21 G 18 C:., g 15 c::
12 9
6 3
2 0 --
0 1.00 1.13 Figure 5.
NFS North Site-SU6 and SU? Surface Soil Characterization Revision 1 1.25 pCi/g 138 1.50 Number of Values Minimum Maximum SD Skewness Kurtosis 0Mean 0Median
~ Normal Distribution D Less Bins D More Bins SU6 In-Situ Descriptive Statistics Th-232 wood.
Page 6 FSS Report Addendum September 2018 63 0.90 1.53 0.12
-2.84 9.57 1.41 1.46
Table 2. SU6 In-Situ Corehole Gamma Spectrometry Measurements Corehole Net Gross Location K-40 Am-241
[cps]
[cps]
750 137 153 751 152 151 752 249 177 753 252 177 754 255 180 755 228 175 756 247 175 757 249 181 758 251 179 759 248 177 760 252 177 761 258 176 762 253 179 763 246 182 764 247 177 765 244 176 766 242 176 767 246 177 768 242 174 769 249 178 770 241 178 771 239 173 772 246 175 773 242 175 774 247 176 775 244 175 776 271 184 777 247 174 778 242 173 779 241 174 780 250 177 781 243 180 782 264 180 783 261 185 784 250 175 785 245 175 786 249 176 787 240 184 788 237 185 789 243 179 NFS North Site-SU6 and SU? Surface Soil Characterization Revision 1 Gross Net U-235 Ra-226
[cps]
[cps]
164 10 165 10 196 11 198 12 201 12 192 10 195 10 198 10 200 10 197 11 199 11 197 12 197 11 196 10 196 11 194 11 193 10 199 11 195 11 198 11 195 10 189 10 195 11 191 11 196 11 193 11 204 9
195 10 191 11 192 11 196 10 197 10 199 10 204 9
192 9
192 11 194 10 200 11 198 12 195 10 wood.
[cps]
[pCi/g]
20 1.39 20 1.39 21 1.46 21 1.46 22 1.53 21 1.46 21 1.46 21 1.46 21 1.46 21 1.46 22 1.53 22 1.53 22 1.53 20 1.39 21 1.46 21 1.46 21 1.46 22 1.53 21 1.46 22 1.53 20 1.39 20 1.39 21 1.46 21 1.46 21 1.46 21 1.46 21 1.46 21 1.46 21 1.46 21 1.46 21 1.46 21 1.46 21 1.46 20 1.39 21 1.46 21 1.46 21 1.46 21 1.46 20 1.39 19 1.32 FSS Report Addendum September 2018
Table 2. SU6 In-Situ Corehole Gamma Spectrometry Measurements Corehole Net Gross Gross Net Net Th-232 Net Th-232 Location K-40 Am-241 U-235 Ra-226
[cps]
[pCi/g]
[cps]
[cps]
[cps]
[cps]
790 255 177 195 10 20 1.39 791 252 182 199 11 19 1.32 792 254 174 192 11 21 1.46 793 252 176 195 10 21 1.46 794 71 124 118 10 13 0.90 795 104 156 149 10 15 1.04 796 233 183 197 12 21 1.46 797 245 179 196 10 19 1.32 798 257 181 201 11 20 1.39 799 248 181 197 10 19 1.32 800 199 165 176 11 20 1.39 801 184 159 169 11 19 1.32 802 239 176 193 10 20 1.39 803 251 180 197 10 20 1.39 804 248 181 201 10 19 1.32 805 249 177 196 10 20 1.39 806 243 179 195 9
20 1.39 807 232 171 186 9
20 1.39 808 244 173 190 10 20 1.39 809 179 165 171 9
18 1.25 2.1.2 Surface Soil Samples Soil samples were collected from the top 6 inches of surface soil at each of the 60 core hole locations in SU6. Samples were collected, packaged, labeled, and transferred to the NFS Non-Destructive-Assay (NDA) laboratory in accordance with the FSP.
Each sample was analyzed by the NFS NDA laboratory in September/October 2017 for U-235, Th-232, Am-241, and U-238 via gamma spectroscopy. Activity results were moisture-corrected.
Descriptive statistics and a data histogram for each isotope are provided in the sequence of figures from Figure 6 to Figure 8. The generated histograms display a background, fitted normal distribution curve providing a visual indication of the normality of the data or lack thereof. The individual sample results are all below the applicable site surface DCGLs provided in Table 1. The individual analytical results for all SU6 soil samples and field duplicate measurements are presented in Table 3.
Table 3 includes Sum of Fractions (SOF) calculations for each sample location and the SU6 mean, using the isotope of interest versus the respective surface soil DCGL. To be conservative, isotopes NFS North Site-SU6 and SU? Surface Soil Characterization Revision 1 wood.
Page 8 FSS Report Addendum September 2018
of interest with reported activities less than O were assigned a value of O for the calculation. All SOF scores are below unity (1.0).
30 27 24 21 B' 18 C:
Ql fr 15 Ql Li:
12 9
6 3
0
-0.26 SU6 Am-241 Soil Samples 0.00 0.26 pCi/g 0.52 Am-241 Number of Values Minimum Maximum SD Skewness Kurtosis 0
Mean 0
Median
~
Normal Distribution O Less Bins 0
More Bins 0.78 Figure 6.
SU6 Soil Sample Statistics Summary Am-241 16 14 12 10 g
~ 8 Ql U:
6 4
2 0.03 0.05 SU6 U-235 Soil Results 0.08 0.11 0.14 pCi/g 0.16 0.19 U-235 Number of Values Minimum Maximum SD Skewness Kurtosis 0 Mean D Median
~ N01mal Distribution D Less Bins D More Bins 0.22 0.24 0.27 Figure 7.
SU6 Soil Sample Statistics Summary U-235 NFS North Site-SU6 and SU? Surface Soil Characterization Revision 1 wood.
Page 9 FSS Report Addendum September 2018 66
-0.37 0.93 0.26 1.28 2.07 0.15 0.04 66 0.00 0.27 0.06 0.52 0.32 0.12 0.12
SU6 Th-232 Soil Samples Th-232 Number of Values 14 Minimum Maximum 12 SD Skewness 10 Kurtosis
~
0Mean
<:: 8 Q)
OMedian (T
Q)
Li:
~ Normal Distribution 6
OLess Bins 4
OMoreBins 2
0 0.39 0.78 117 1 56 195 2.34 pCi/g Figure 8.
SU6 Soil Sample Statistics Summary Th-232 NFS North Site-SU6 and SU? Surface Soil Characterization Revision 1 wood.
Page 10 FSS Report Addendum September 2018 66 0.38 2.33 0.41
-0.42 0.38 1.49 1.52
Table 3.
Date Net Sample ID Weight Analyzed (g) 0750-SS-FS 9/12/2017 305.2 0751-SS-FS 9/12/2017 297.2 0752-SS-FS 9/12/2017 282.3 0753-SS-FS 9/12/2017 278.6 0754-SS-FS 9/12/2017 272.3 0755-SS-FS 9/12/2017 276.1 0756-SS-FS 9/12/2017 264.4 0756-SS-FD 10/4/2017 266.8 0757-SS-FS 9/13/2017 260.5 0758-SS-FS 9/13/2017 256.1 0759-SS-FS 9/13/2017 280.2 0759-SS-FD 10/5/2017 281 0760-SS-FS 9/13/2017 301.9 0761-SS-FS 9/14/2017 281.6 0762-SS-FS 9/14/2017 284.4 0763-SS-FS 9/14/2017 247.2 0764-SS-FS 9/14/2017 250 0765-SS-FS 9/14/2017 269.5 0766-SS-FS 9/15/2017 263.7 0767-SS-FS 9/15/2017 259.6 0768-SS-FS 9/15/2017 285 0769-SS-FS 9/15/2017 258.3 0770-SS-FS 9/15/2017 263.8 0771-SS-FS 9/15/2017 286.9 0772-SS-FS 9/18/2017 282.7 0773-SS-FS 9/18/2017 252.1 0774-SS-FS 9/18/2017 248.2 0775-SS-FS 9/18/2017 289 0776-SS-FS 9/18/2017 263.5 0777-SS-FS 9/19/2017 268.6 0778-SS-FS 9/19/2017 262.5 0779-SS-FS 9/19/2017 258.1 0780-SS-FS 9/19/2017 282.8 0781-SS-FS 9/19/2017 269.9 0782-SS-FS 9/19/2017 256.6 NFS North Site-SU6 and SU? Surface Soil Characterization Revision 1 SU6 Soil Sample Results Moisture-Corrected Result (pCi/g)
Moisture U-235 1.9 0.08 7.2 0.1 11.9 0.15 11 0.05 9.3 0.19 8.2 0
8.7 0.09 6.9 0.12 10.2 0.13 11.3 0.13 9.2 0.24 10.1 0.22 13.1 0.12 10.8 0.17 10 0.18 8.5 0.13 8.8 0.14 8.3 0.1 13.3 0.17 10.3 0.15 13.6 0.11 12 0.04 10.7 0.07 13.1 0.06 9.9 0.12 10.4 0.27 10.8 0.1 13.1 0.12 9.8 0.27 10.1 0.05 12.3 0.12 11.4 0.1 11.4 0.05 8.3 0.1 11.5 0.09 wood.
Page 11 U-238 4.33 0
9.89 1.86 3.55 11.88 11.27 3.94 0
6.14 2.74 10.62 1.22 1.92 5.02 0
1.29 0
3.84 0
0 0
0 4.47 0
0 0
0 5.54 0
0 0
0 0.52 0
Th-232 Am-241 1.52 0.61 1.89 0.29 1.49 0
1.81 0.4 1.4 0.52 1.77 0
1.52 0.56 1.53 0
2.03 0
2.04 0
2.33 0.33 1.34 0.09 1.57 0.17 2.06 0.04 1.69 0.04 1.94 0
1.53
-0.37 1.48 0.05 1.31 0
1.49 0
0.99 0
1.17 0.23 1.25 0
1.42 0.1 1.89 0.26 1.17 0.16 1.37 0.33 1.77 0.01 2.08 0
1.34 0.55 1.6 0
1.59 0
1.66 0.27 1.81 0.27 1.37 0
FSS Report Addendum September 2018 SOF 0.43 0.51 0.44 0.50 0.40 0.52 0.45 0.43 0.55 0.57 0.64 0.40 0.43 0.57 0.48 0.53 0.42 0.40 0.37 0.40 0.27 0.32 0.34 0.40 0.51 0.32 0.37 0.48 0.58 0.37 0.43 0.43 0.45 0.49 0.37
Table 3.
Date Net Sample ID Weight Analyzed (g) 0783-SS-FS 9/19/2017 268.1 0784-SS-FS 9/19/2017 269.6 0785-SS-FS 9/19/2017 274.5 0786-SS-FS 9/20/2017 275.7 0787-SS-FS 9/20/2017 268.2 0788-SS-FS 9/21/2017 255.6 0789-SS-FS 9/21/2017 258.8 0790-SS-FS 9/21/2017 251.5 0791-SS-FS 9/21/2017 278.8 0792-SS-FS 9/21/2017 254.4 0793-SS-FS 9/25/2017 265.4 0794-SS-FS 9/25/2017 252 0795-SS-FS 9/25/2017 260.8 0796-SS-FS 9/25/2017 258.4 0797-SS-FS 9/25/2017 268.4 0798-SS-FS 9/25/2017 265 0799-SS-FS 9/26/2017 271.3 0800-SS-FS 9/26/2017 248.6 0801-SS-FS 9/26/2017 246.8 0802-SS-FS 9/26/2017 240.4 0803-SS-FS 9/26/2017 256.7 0804-SS-FS 9/26/2017 265.3 0805-SS-FS 9/26/2017 232.9 0806-SS-FS 9/26/2017 247.8 0807-SS-FS 9/26/2017 224.3 0808-SS-FS 9/26/2017 256 0809-SS-FS 9/26/2017 246.9 0809-SS-FD 10/5/2017 253.1 SU6 Mean Standard Deviation NFS North Site-SU6 and SU? Surface Soil Characterization Revision 1 SU6 Soil Sample Results Moisture-Corrected Result (pCi/g)
Moisture U-235 7.5 0.1 11.7 0.09 11.9 0.17 11 0.09 8.8 0.25 10.8 0.09 11.8 0.21 8.9 0.24 8.9 0.14 11.2 0
9.2 0.21 10.3 0.1 12.4 0.07 10.1 0.08 10.7 0.13 9.4 0.09 7.7 0.11 8.7 0.05 12 0.14 11.6 0.1 9.7 0.15 8.5 0.16 10.9 0.09 12 0.13 15.6 0.15 9.3 0.12 14.3 0.08 14.5 0.15 0.12 0.06 wood.
Page 12 U-238 0
0 0
9.5 17.5 0
18.62 2.51 0
0.36 11.11 2.38 0
0 3.66 0
16.08 0
5.04 0
0 0
0 12.15 1.62 18.03 13.62 0.94 3.54 5.22 Th-232 Am-241 0.82 0
1.14 0
1.52 0
1.24 0.06 2.17 0
1.03 0
0.38 0
1.13 0.93 1.11 0
0.67 0
1.07 0.45 1.3 0
1.03 0
1.25 0.05 1.52 0.58 1.24 0
1.89 0.27 1.91 0.36 1.71 0
1.69 0
1.61 0.35 1.94 0
1.66 0
1.94 0.04 1.63 0.87 1.04 0.14 1.7 0.2 0.86 0.10 1.50 0.15 0.38 0.23 FSS Report Addendum September 2018 SOF 0.22 0.31 0.41 0.37 0.65 0.28 0.17 0.32 0.30 0.18 0.33 0.36 0.28 0.34 0.43 0.34 0.57 0.52 0.48 0.46 0.44 0.53 0.45 0.57 0.45 0.34 0.51 0.24 0.42
2.1.3 Gamma Scanning Results Gamma scanning was performed using the ScanPlot5M system, with a large volume (-4L),
spectroscopy-grade Nal detector, digital spectrometer, and a survey-grade GPS system configured on a push cart. Spectral data was acquired every second while the push cart moved at a survey speed of approximately 1 meter per second (mps), on 1 m transects. Each data point is representative of an area of approximately 5 m2. The spectral data was processed in a manner similar to the in-situ static measurement data. Net photo peak count rates were determined for a variety of ROis for isotopes of interest.
Two-dimensional, color-scale maps of the gross gamma, gross Am-241, gross U-235, and net Th-232 radiological count rates were generated and are provided in the sequence of figures from Figure 9 to Figure 1:2. The plotted scan data for SU6 reveals that the surface activity is essentially uniform and that there are no spatially correlated elevated areas of concern.
Figure 9.
NFS North Site-SU6 and SU? Surface Soil Characterization Revision 1 SU6 Gross Gamma Map (cps) wood.
Page 13 FSS Report Addendum September 2018
Figure 10.
Figure 11.
NFS North Site-SU6 and SU? Surface Soil Characterization Revision 1 SU6 Am-241 Gamma Map (cps)
SU6 U-235 Gamma Map (cps) wood.
Page 14 FSS Report Addendum September 2018
Figure 12.
SU6 Th-232 Gamma Map (cps) 2.2 SURVEY UNIT 7 2.2.1 In-Situ Static Gamma Spectroscopy Measurement In-situ static measurements were taken at each corehole location (Figure 13) that were established as part of the subsurface characterization of the North Site. The measurements were performed by positioning the ScanPlo fM push cart platform over each of the 32 corehole locations, and collecting a stationary, 5-minute, spectral gamma measurement. Gamma spectra were collected using Wood proprietary data collection software.
NFS North Site-SU6 and SU? Surface Soil Characterization Revision 1 wood.
Page 15 FSS Report Addendum September 2018
Ii s
lo I
~
a Iii NFS North Site-ZIIIO 0
7009 C
7007 7003 2!00 IWltOO C
0 70)11 70!)1 0
C 0
0 C
7023 1020 70\\l6 702' 1027 0
C O
C C
O 7015 7019 *:~
~
0 C
7010 ~
- Legend o Sa""le Locelion CJ Survey Uni Nudear Fue1 Servioe$
Erwin, TN
- MACTEC Figure 13.
SU7 Sample Locations wood.
SU6 and SU? Surface Soil Characterization Revision 1 Page 16
__ 1 I
I 1 I I
J l
J I
J i I l
Prepan!d/0 te. ~
07/19110 J
~
I AUL 07/ 1Ql10 S\\JNey Unit 7 Projecl 9120-07 -1235 Figure 7 FSS Report Addendum September 2018
Subsequently, the spectra were processed in order to calculate the gross counts in a number of ROI associated with the isotopes of interest. Net photo peak counts were then derived for K-40, Ra-226, and Th-232. The net Th-232 count rates were also converted to soil concentrations in pCi/g for direct comparison with the surface soil DCGL. Ra-226 and K-40 were reported to be able to isolate the gamma signals from the isotopes of interest from the naturally present isotopes.
The generated histograms include summary statistics and display a fitted normal distribution curve as a background, providing a visual indication of the normality of the data or lack thereof.
The in-situ data for all isotopes did not follow a normal distribution. Histograms are provided in the sequence of figures from Figure 14 to Figure 17. Table 4 presents the results of the in-situ static measurements.
9 8
7 6
g5 Q)
~4 3
2 0
21 41 SU7 Net K-40 cps 62 82 103 124 144 165 185 206 226 cps NetK-40cps Number of Values 32 Minimum 22.08 Maximum 227.93 SD 73.28 Skewness 0.03 Kurtosis
- 1.64 0Mean 117.05 OMedian 11 9.89
~ Normal Distribution D Less Bins D More Bins Figure 14.
SUl /n-Situ Descriptive Statistics K-40 NFS North Site-SU6 and SU? Surface Soil Characterization Revision 1 wood.
Page 17 FSS Report Addendum September 2018
10 9
8 7
is 6 C:
Q) 5
- i CT Q)
Li:
4 3
2 0
Title 71 SU7 Gross Am-241 94 118 cps 141 165 GrossAm-241 [cps]
Number of Values 35 Minimum 64.07 Maximum 181.81 SD 40.74 Skewness
-0.11 Kurtosis
- 1.57 0Mean 121.35 D Median 134.01
~ Normal Distribution D Less Bins D More Bins Figure 15.
SU7 In-Situ Descriptive Statistics Am-241 SU 7 Gross U-235 Gross U-235 [cps) 9 Number of Values 35 Minimum 52.58 8
Maximum 194.06 7
SD 49.02 Skewness
- 0.16 6
Kurtosis
- 1.58
- ,., g5 0Mean 123.37 Q) 0Median 131.60
- i CT
~4
~
Normal Distribution 3
D Less Bins 2
D More Bins 0
57 85 113 141 170 198 cps Figure 16.
SU7 In-Situ Descriptive Statistics U-235 NFS North Site-SU6 and SU? Surface Soil Characterization Revision 1 wood.
Page 18 FSS Report Addendum September 2018
SU7 Net Th-232 Net Th-232b (pCi/g]
9 Number of Values 8
Minimum Ma~imum 7
SD 6
Skewness t5 Kurtosis 0Mean O"
!! 4 LL.
D Median 3
~
Normal Distribution 2
D Less Bins 0More8ins 0
0.26 0.51 077 1.02 1.28 1.53 pCi/g Figure 17.
SUl In-Situ Descriptive Statistics Th-232 NFS North Site-SU6 and SU? Surface Soil Characterization Revision 1 wood.
Page 19 FSS Report Addendum September 2018 35 0.29 1.57 0.42
- 0.34
-1.45 0.98 1 08
bl s
Situ Corehole G Net Gross Corehole K-40 Am-241 Location
[cps]
[cps]
7001 146 157 7002 225 182 7003 127 146 7004 141 156 7005 228 182 7006 161 151 7007 203 168 7008 174 167 7009 185 156 7010 97 122 7011 26 71 7012 84 135 7013 48 92 7014 36 79 7015 113 105 7016 27 66 7017 22 68 7018 62 84 7019 27 75 7020 25 71 7021 22 64 7022 52 92 7023 205 160 7024 170 134 7025 74 99 7026 191 154 7027 206 152 7028 57 73 7029 173 143 7030 206 152 7031 195 149 7032 36 73 NFS North Site-SU6 and SU7 Surface Soil Characterization Revision 1 Gross U-235
[cps]
162 191 145 159 194 159 178 173 166 122 61 132 88 70 108 61 56 79 65 60 53 94 173 144 97 167 168 71 153 170 165 66 wood.
Page 20 S,
Net Ra-226
[cps]
10 11 9
10 11 10 10 11 10 9
7 10 8
7 8
7 6
7 6
6 6
8 9
9 7
9 10 7
9 10 9
7 M
Net Net Th-232 Th-232
[cps]
[pCi/g]
23 1.57 20 1.39 18 1.23 18 1.26 20 1.36 18 1.29 20 1.38 19 1.29 18 1.27 13 0.94 5
0.38 15 1.08 13 0.92 7
0.46 12 0.82 7
0.47 4
0.29 9
0.60 7
0.51 7
0.45 4
0.31 14 1.00 20 1.40 17 1.18 9
0.65 20 1.41 20 1.41 7
0.52 18 1.26 20 1.40 19 1.32 7
0.50 FSS Report Addendum September 2018
2.2.2 Surface Soil Samples Soil samples were collected from the top 6 inches of surface soil at each of the 32 core hole locations in SU7. An additional sample was collected from an area of elevated gamma scan measurements within SU7 and labeled 7-HS-SS-FS. Samples were collected, packaged, labeled, and transferred to the NFS NOA laboratory in accordance with the FSP.
Samples were analyzed by the NFS NDA laboratory in September/October 2017 for U-235, U-238, Th-232, and Am-241 via gamma spectroscopy. Results were moisture-corrected to calculate activity. The sample results for each isotope are summarized with histograms and descriptive statistics provided in the sequence of figures from Figure 18 to Figure 20. The generated histograms display a background, fitted normal distribution curve providing a visual indication of the normality of the data or lack thereof. The individual corehole sample results are all below the applicable site surface DCGLs provided in Table 1.
SU7 Am-241 Am-241 Number of Values 24 Minimum 22 Maximum 20 SD 18 Skewness 16 g 14 II)
Kurtosis 0Mean D Median El-12 II)
~ Normal Distribution U::
10 8
D Less Bins 6
DMoreBins 4
2 0
0.00 0.08 0.1 7 0.25 0.34 0.42 pCi/g Figure 18.
SU7 Soil Sample Statistics Summary Am-241 NFS North Site-SU6 and SU7 Surface Soil Characterization Revision 1 wood.
Page 21 FSS Report Addendum September 2018 34 0.00 0.42 0.09 2.61 7.38 0.05 0.00
SU7 U-235 U-235 14 Number of Values Minimum 12 Maximum SD 10 Skewness Kurtosis 0Mean D Median r;' 8 C:
Q)
~
Normal Distribution CT Q)
U:: 6 4
D Less Bins OMoreBins 2
1 0
0
- 0.00 0.09 0.19 0.28 0.38 0.47 pCi/g Figure 19.
SUl Soil Sample Statistics Summary U-235 8
7 6
5 G
s:::
!!l 4 CT Q)
Li:
3 2
0 0.00 SU7 Th-232 0.46 0.92 1.37 pCi/g Th-232 Number of Values Minimum Maximum SD Skewness Kurtosis 0Mean 0 Median
~ Normal Distribution 0 Less Bins 0 More Bins 1.83 2.29 Figure 20.
SUl Soil Sample Statistics Summary Th-232 NFS North Site-SU6 and SU? Surface Soil Characterization Revision 1 wood.
Page 22 FSS Report Addendum September 2018 34 0.00 0.47 0.09 1.67 5.39 0.12 0.11 34 0.00 2.29 0.71
- 0.08
- 1.28 1.05 1.22
The individual analytical results for all SU7 soil samples and field duplicate measurements are presented in Table 5. Additionally, Table 5 includes SOF calculations for each isotope of interest versus its respective surface soil DCGL. To be conservative, isotopes of interest with reported activities less than O were assigned a value of O for the calculation.
A single soil sample (7-HS-SS-FS) from elevated Area A was collected from SU7 and submitted for analysis with the core hole samples.1 The analytical result of this sample was above the surface DCGL for Th-232. This sample and the detailed analysis of the gamma survey data prompted the elevated measurement investigation discussed in Section 2.3.
T bl 5 a e SU7 S *t S Ol l R ampe esu ts Net Moisture-Corrected Result (pCi/g) a Date Sample ID Weight SOF Analyzed Moisture (g)
U-235 U-238 Th-232 Am-241 7001-SS-FS 9/27/2017 237 12.8 0.17 0
1.38 0
7002-SS-FS 9/27/2017 261 17 0
12.28 1.51 0.02 7003-SS-FS 9/27/2017 255.2 10.4 0.07 2.76 1.3 0
7004-SS-FS 9/27/2017 256.6 10.7 0
7.66 1.66 0
7005-SS-FS 9/27/2017 262.4 11 0.15 11.74 2.04 0.42 7005-SS-FD 10/4/2017 277.5 11.2 0.10 0
0.95 0
7006-SS-FS 9/27/2017 259.4 11.5 0.06 4.13
- 1.72 0
7007-SS-FS 9/28/2017 272.3 14 0.25 0
2.06 0.03 7008-SS-FS 9/28/2017 245.3 13.7 0.19 2.04 1.39 0.22 7009-SS-FS 9/28/2017 260.2 14 0.25 12.78 2.29 0
7010-SS-FS 9/28/2017 273.4 13.4 0.14 14.57 1.36 0
7011-SS-FS 9/28/2017 349.3 1.1 0.1 0.7 0.56 0.05 7012-SS-FS 9/29/2017 243.6 12.1 0.09 0
0.55 0
7013-SS-FS 9/29/2017 240 19.3 0.47 0
1.05 0
7014-SS-FS 9/29/2017 383.5 0.9 0.1 0
0.07 0
7015-SS-FS 9/29/2017 259.4 11.3 0.18 0
1.14 0
7016-SS-FS 9/29/2017 296.6 4
0.1 0
0.25 0.24 7017-SS-FS 10/2/2017 359.2 0.8 0.04 0
0 0
7018-SS-FS 10/2/2017 307 1.7 0.13 0
0.15 0.08 7019-SS-FS 10/2/2017 344.5 3.4 0.13 0
0.09 0
7020-SS-FS 10/2/2017 342.8 0.8 0.13 1.37 0.22 0.1 7021-SS-FS 10/2/2017 353.4 0.3 0.1 0
0.19 0
1Field review of the gamma scans. described in Section 2.2.3, identified an area of elevated measurements. Sample number 7-HS-SS-FS was collected to confirm the presence of elevated material.
NFS North Site-SU6 and SU? Surface Soil Characterization Revision 1 wood.
Page 23 FSS Report Addendum September 2018 0.38 0.45 0.36 0.47 0.59 0.26 0.48 0.56 0.39 0.66 0.42 0.16 0.15 0.29 0.02 0.31 0.07 0.00 0.04 0.03 0.07 0.05
Table 5.
SU7 Soil Sample Results Date Net Moisture-Corrected Result (pCi/g) a Sample ID Weight SOF Analyzed (g)
Moisture U-235 U-238 Th-232 Am-241 7022-SS-FS 10/2/2017 273.4 8
0.21 1.95 1.98 0
0.54 7023-SS-FS 10/2/2017 266 16.3 0.08 0
1.46 0.07 0.40 7024-SS-FS 10/2/2017 260.9 18.2 0.13 2.75 1.32 0
0.37 7025-SS-FS 10/2/2017 383.3 1.6 0
0 0
0.11 0.00 7026-SS-FS 10/2/2017 256 14.5 0.23 5.07 1.33 0
0.38 7027-SS-FS 10/2/2017 260.4 13.5 0.14 0
0.86 0
0.23 7028-SS-FS 10/3/2017 352.2 0.7 0.12 12.41 0.28 0.2 0.12 7029-SS-FS 10/3/2017 263.4 11.7 0.05 6.73 1.68 0.01 0.48 7030-SS-FS 10/4/2017 270.7 13 0.08 0
1.56 0
0.42 7030-SS-FD 10/4/2017 273.7 11.8 0.09 2.16 1.99 0
0.54 7031-SS-FS 10/4/2017 274.6 13.8 0.13 2.7 0.94 0
0.26 7032-SS-FS 10/4/2017 388.6 0.4 0
0 0.26 0.06 0.07 7-HS-SS-FS 9/13/2017 267.1 7.2 4.3 57.66 32.21 0
8.95 SU7 Mean 0.24 4.61 1.94 0.05 0.54 Standard Deviation 0.70 10.12 5.24 0.09 (a> Values highlighted in BOLD text exceed the DCGLw value (NFS 2006) 2.2.3 Gamma Scanning Results Gamma scanning was performed using the ScanPlot5M system, with a large volume (-4L),
spectroscopy-grade Nal detector, digital spectrometer, and a survey-grade GPS system configured on a push cart. Spectral data was acquired every second while the push cart moved at a survey speed of approximately 1 mps, on 1 m transects. Each data point is representative of an area of approximately 5 m2. The spectral data was processed in a manner similar to the in-situ static measurement data. Net photo peak count rates were determined for a variety of ROis for the isotopes of interest.
Two-dimensional, color-scale maps of the gross gamma, gross Am-241, gross U-235, and net Th-232 radiological count rates were generated and are provided in the sequential figures from Figure 21 to Figure 24.
The field assessment of the gamma survey data revealed a small area with elevated gamma measurements prompting the collection of a single soil sample labeled 7-HS-SS-FW. This sample was included with the other samples analyzed by the NFS NDA laboratory and is included in Table 5.
NFS North Site-SU6 and SU? Surface Soil Characterization Revision 1 wood.
Page 24 FSS Report Addendum September 2018
Figure 21.
Figure 22.
NFS North Site-SU6 and SU7 Surface Soil Characterization Revision 1 SU7 Gross Gamma Map (cps)
SU7 Gross Am-241 Gamma Map (cps) wood.
Page 25 FSS Report Addendum September 2018
Figure 23.
Figure 24.
NFS North Site-SU6 and SU? Surface Soil Characterization Revision 1 Gross U*23S O.t*l (No Aggregat,on)
SU7 Gross U-235 Gamma Mop (cps)
Ntt Th*232 O.t* (No Aggregotion) 170.43 SU7 Net Th-232 Gamma Mop (cps) wood.
Page 26 FSS Report Addendum September 2018
2.3 PHASE 2 INVESTIGATION Detailed analysis of the field data identified two small areas with elevated measurements (identified hereafter as Areas A and B). Area A was identified during field operations and was confirmed by the laboratory analysis of sample 7-HS-SS-FW. Both areas occur in surface drainage features (swales) that have been constructed to manage and facilitate surface water drainage on the North Site. Area A has manifestly higher gamma count rates. Area B was detected only after the scan data was processed and spatially mapped. The processed and compiled spectral scan data indicated that the elevated gamma signal is largely contributed by gamma energies corresponding to Th-232.
A locally elevated measurement investigation plan was developed ~nd included as Addendum 1 to the FSP in October 2017. These two small areas, labeled as A and B were both located on the border of SU7 and are comparable in size (Figure 25). Samples were collected in January/February 2018 from both areas.
NFS North Site-SU6 and SU7 Surface Soil Characterization Revision 1 Figure 25.
wood.
Page 27 Areas A & B Th-232 Oet-1 (No Aggregation)
FSS Report Addendum September 2018 15109 Of MOfe
2.3.1 Systematic Sampling Design The systematic sampling design is summarized here with the details provided in the FSP Addendum (Wood 2018). A systematic set of surface soil samples were collected in an areal pattern. The central point is positioned over the location of the observed highest gamma radiation count rate. Four samples were collected from each of the six concentric circles, with sample collection points chosen at every other radian and alternating on each circle, resulting in the collection of 25 samples for each area. The samples were numbered starting with 1 at the upper right corner of the largest circle and spiraling in counterclockwise to the center point labeled 25. Appendix A provides the GPS coordinates for the samples collected in Areas A and B.
R08m R 1 Om '
.::~-:if,. * *.. it R45m-;' ~~'>;' *::.i::.* \\ *
--*----; --*-*~,*~*~
I 2.3.2 Area A
- .*,/... :i..
'.*<'_~ '
Figure 26.
Area Sampling Plan The Area A samples were collected, labeled, and submitted to the NFS NDA laboratory for analysis.
Samples were analyzed in February 2018 for U-235, U-238, Th-232, and Am-241 via gamma spectroscopy. Results were moisture-corrected and are provided in Table 6.
NFS North Site-SU6 and SU? Surface Soil Characterization Revision 1 wood.
Page 28 FSS Report Addendum September 2018
Table 6 Area A Soil Sample Results Sample ID
% Moist.
MOISTURE-CORRECTED DATA (pCi/g) a U-235 U-238 Th-232 Am-241 A01-NN33-FS 13.3 0.13 0
0.50 0
A02-NE45-FS 22.7 0.30 16.93 2.68 0.56 A03-EE33-FS 22 0.20 16.85 1.88 0.03 A04-SE45-FS 27.5 0.28 6.66 2.06 0.24 A05-SS33-FS 22.7 1.79 33.17 5.09 0
A06-SW45-FS 23.1 0.20 0
1.70 0
A07-WW33-FS 22.2 0.30 13.10 1.98 0.08 A08-NW45-FS 22.2 1.20 19.28 5.35 0
A09-NW22-FS 18.8 1.70 10.28 1.84 0
A10-NN15-FS 27.7 0.45 9.09 2.44 0
Al0-NN15-FD 24.5 0.31 0
0.75 0.58 All-NE22-FS 10 0
2.59 0.90 0
A12-EE15-FS 24.7 0.61 3.88 3.29 0.87 Al3-SE22-FS 22.7 0.67 0
5.63 0
Al3-SE22-FD 23.2 0.59 14.00 6.52 0.16 A14-SS15-FS 11.2 1.10 25.63 2.08 0
A15-SW22-FS 26.2 0.51 1.29 3.02 0
A15-SW22-FD 24.9 0.18 5.80 1.99 0.14 A16-WW15-FS 11.1 0.16 8.70 1.11 0
A17-WW08-FS 12.7 1.55 6.11 1.17 0
A18-SW10-FS 12.4 0.84 17.89 2.00 0
A19-SS08-FS 16 1.45 22.80 1.65 0
A20-SE10-FS 21 1.10 20.65 6.99 0
A21-EE08-FS 26.6 1.03 0
5.72 0
A22-NE10-FS 23.4 0.56 7.79 2.67 0
A23-NN08-FS 16.7 0.51 9.70 3.45 0
A24-NW10-FS 15.9 3.31 41.17 6.23 0
A25-NNOO-FS 19 5.77 70.95 48.88 0
<*> Values highlighted in BOLD text exceed the DCGLw value (NFS 2006)
The sample results reported in Table 6 are the Phase 2 investigation samples that were collected within the region where locally elevated gamma radiation was detected during the surface scan survey, triggering the additional investigation (Phase 2). This locally elevated area, Area A, was further investigated to assess compliance with the DCGLEMc criteria. As expected, some of the soil samples collected within the area identified as locally elevated by the surface gamma scan surveys NFS North Site-SU6 and SU? Surface Soil Characterization Revision 1 wood.
Page 29 FSS Report Addendum September 2018
contained concentrations of radioactivity in excess of the applicable DCGLw for Th-232. The laboratory sample results were entered in conjunction with their spatial coordinates into GIS software, as shown in Figure 27, to allow for geospatially interpolation.
Figure 27.
NFS North Site-SU6 and SU? Surface Soil Characterization Revision 1 Leg d
....... si::::=====:::J1~.j Erwin TN Survey Units 6 and 7 Survey Data Area A c foSter Area A Interpolation wood.
Page 30 FSS Report Addendum September 2018
Evaluation of Figure 27produced an appropriate set of spatially weighted values. Using the area factors provided in Section 5.2.6 of the FSS Plan, DCGLemc were calculated for evaluation of the isotopes of interest. The evaluation shows that for all grids Am-241 (Table 7), U-235 (Table 8), and Th-232 (Table 9) are below the DCGLemc.
The isotope contributions to each SOF were also calculated.
r; bl 7 a e A
A S t ll W. ht d A 241 \\I'. l rea
>PO LO '.y eiq, e m-a ues Length of MEAN EMC Area EMC DCGLeMc Am-241 Evaluation (pCi/g)
(m2)
Area Am-241 Contribution Grid (ft)
Factor a (pCi/g) to SOF 3
-0.02 1.00 9.54 213.32
-0.010%
5
-0.01 2.32 8.36 186.91
-0.007%
7 0.02 4.55 7.43 166.08 0.011%
9 0.06 7.53 6.76 151.17 0.037%
11 0.09 11.24 6.27 140.18 0.058%
13 0.10 15.70 5.88 131.54 0.071%
15 0.10 20.90 5.57 124.56 0.079%
17 0.10 26.85 5.31 118.76 0.084%
19 0.11 33.54 5.05 112.92 0.090%
21 0.11 40.97 4.79 107.14 0.096%
23 0.11 49.15 4.57 102.14 0.102%
a EMC Area Factor is based of the area factors contained in the FSS Plan, Section 5.2.6.
r; bl 8 a e A
A S t' ll W. ht d U 235 \\I'. l rea
,pa LO IY eiq e a ues Length of MEAN EMC Area EMC DCGLeMc U-235 Evaluation (pCi/g)
(m2)
Area U-235 Contribution Grid (ft)
Factor a (pCi/g) to SOF 3
3.34 1.00 5.8 24.00 13.92%
5 2.34 2.32 3.84 15.90 14.69%
7 1.71 4.55 2.76 11.42 14.99%
9 1.32 7.53 2.15 8.91 14.86%
11 1.07 11.24 1.82 7.51 14.21%
13 0.90 15.70 1.67 6.91 13.01%
15 0.78 20.90 1.55 6.43 12.18%
17 0.70 26.85 1.46 6.04 11.62%
19 0.64 33.54 1.40 5.78 11.14%
21 0.60 40.97 1.35 5.60 10.70%
23 0.56 49.15 1.32 5.45 10.36%
a EMC Area Factor is based of the area factors contained in the FSS Plan, Section 5.2.6.
NFS North Site-SU6 and SU7 Surface Soil Characterization Revision 1 wood.
Page 31 FSS Report Addendum September 2018
r; bl 9 a e A
. ll W. h d Th 232 ~ I rea patto !y e1q. te a ues Length of MEAN EMC Area EMC DCGLeMc Th-232 Evaluation (pCi/g)
(m2)
Area Th-232 Contribution Grid (ft)
Factor a (pCi/g) to SOF 3
12.61 1.00 8.4 25.12 50.2%
5 6.65 2.32 4.92 14.71 45.2%
7 4.15 4.55 3.30 9.86 42.1%
9 2.88 7.53 2.48 7.41 38.8%
11 2.16 11.24 1.82 5.43 39.8%
13 1.73 15.70 1.67 4.99 34.6%
15 1.45 20.90 1.55 4.65 31.2%
17 1.26 26.85 1.46 4.37 28.9%
19 1.14 33.54 1.40 4.17 27.2%
21 1.06 40.97 1.35 4.05 26.1%
23 1.01 49.15 1.32 3.94 25.6%
a EMC Area Factor is based of the area factors contained in the FSS Plan, Section 5.2.6.
The SOF contribution from Am-241, U-235, and Th-232 along with the combined SOF values for Area A were calculated and provided as Figure 28, and confirms the SOF score is less than unity (1.0).
Comparison to SOF Criteria Area-A 1.20 Combined...
Th-232...
Am-241...
U-235...
1.00 -------------------------
0.80..
LL 0 0.60 Vl 0.40 0.20
- 0.00 1
Figure 28.
NFS North Site-SU6 and SU? Surface Soil Characterization Revision 1 I
- ~
10 Area (m 2)
Area A SOF Comparison wood.
Page 32 100 FSS Report Addendum September 2018
To complete the SOF evaluation, the area and SU values were combined to ensure the SOF for the entire SU is less than unity, as shown in Table 10.
Table 10.
SU7 & Area A SOF Evaluation Length of EMC Area EMC HS-A SUWAA Combined Evaluation (m2)
Area SOF Score SOF Score SOF Score Decision Grid (ft)
Factor a 3
1.00 5.8 0.64 0.04 0.68 PASS 5
2.32 3.84 0.60 0.04 0.64 PASS 7
4.55 2.76 0.57 0.04 0.61 PASS 9
7.53 2.15 0.54 0.04 0.58 PASS 11 11.24 1.82 0.54 0.04 0.58 PASS 13 15.70 1.67 0.48 0.04 0.52 PASS 15 20.90 1.55 0.43 0.04 0.47 PASS 17 26.85 1.46 0.41 0.04 0.45 PASS 19 33.54 1.40 0.38 0.04 0.42 PASS 21 40.97 1.35 0.37 0.04 0.41 PASS 23 49.15 1.32 0.36 0.04 0.40 PASS a EMC Area Factor is based of the area factors contained in the FSS Plan, Section 5.2.6.
2.3.3 Area B Area B was not identified during the field effort but was clearly seen during the formal data evaluation process. Samples from the elevated area were collected, labeled, and submitted to the NFS NDA laboratory for analysis. Samples were analyzed by the NFS NDA laboratory in February 2018 for U-235, U-238, Th 232, and Am-241 via gamma spectroscopy. Results were moisture-corrected and are provided in Table 11.
NFS North Site-SU6 and SU? Surface Soil Characterization Revision 1 wood.
Page 33 FSS Report Addendum September 2018
T, bl 11 a e A
BS *t S rea Ol l R Lt ampe esu s Sample ID
% Moist.
MOISTURE-CORRECTED DATA (pCi/g)
B03-EE33-FS 29 0.13 0
1.25 0.57 B04-SE45-FS 26.5 0.22 0
1.04 0.32 B05-SS33-FS 23.8 0.27 1.65 1.47 0.35 B06-SW45-FS 23.9 0.29 4.57 1.19 0
B07-WW33-FS 26.8 0.16 8.30 1.18 0
B08-NW45-FS 18.6 0.10 14.82 1.99 0.15 B09-NW22-FS 24.7 0.29 0
1.67 0.12 B10-NN15-FS 23.5 0.45 0
2.07 2.02 B11-NE22-FS 31.6 0.35 19.69 2.35 1.35 B11-NE22-FD 27.1 0.21 3.44 1.75 0.44 B12-EE15-FS 26.7 1.43 0.96 8.77 16.48 B13-SE22-FS 24.8 0.26 0
2.05 1.04 B14-SS15-FS 17.3 0.23 3.85 2.19 0.18 B15-SW22-FS 23.6 0.65 6.11 2.61 5.01 B15-SW22-FD 22.2 0.56 0
3.02 6.53 B16-WW15-FS 24.7 0.28 17.45 1.72 1.07 B17-WW08-FS 26.4 0.65 10.72 3.21 5.18 B18-SW10-FS 40 1.03 0
5.67 12.51 B19-SS08-FS 26.2 1.81 0
10.32 31.49 B20-SE10-FS 25.5 0.46 0
2.22 1.35 B21-EE08-FS 50.6 1.01 0
6.42 18.66 B22-NE10-FS 29.8 1.19 0
5.65 10.07 B23-NN08-FS 24.6 0.82 19.05 3.93 7.47 B24-NW10-FS 25.9 0.16 0
1.21 0
B25-NNOO-FS 39.9 6.18 4.42 15.10 55.31
<*> Values highlighted in BOLD text exceed the DCGLw value (NFS 2006)
The sample results reported in Table 11 are the Phase 2 investigation samples that were collected within the region where locally elevated gamma radiation was detected during the surface scan survey, triggering the additional investigation (Phase 2). This locally elevated area, Area B, was further investigated to assess compliance with the DCGLEMc criteria. As expected, some of the soil NFS North Site-SU6 and SU? Surface Soil Characterization Revision 1 wood.
Page 34 FSS Report Addendum September 2018
samples collected within the area identified as locally elevated by the surface gamma scan surveys contained concentrations of radioactivity in excess of the applicable DCGLw for Th-232.
The laboratory sample results were entered in conjunction with their spatial coordinates into GIS software, as shown on Figure 29, to allow for geospatially interpolation.
Figure 29.
NFS North Site-SU6 and SU7 Surface Soil Characterization Revision 1 Gt jo........ sc:::======>'~,I Erwin, TN Survey Units 6 and 7 Survey Data Area 8 fos er w pC.
Area B Interpolation wood.
Page 35 FSS Report Addendum September 2018
Evaluation of Figure 29produced an appropriate set of spatially weighted values. Using the area factors provided in Section 5.2.6 of the FSS Plan, DCGLemc were calculated for evaluation of the isotopes of interest. The evaluation shows that for all grids Am-241 (Table 12), U-235 (Table 13),
and Th-232 (Table 14) are below the DCGLemc.
The isotope contributions to each SOF were also calculated.
r: bl 12 a e A
BS t" LL W. ht d A 241 \\I'. l rea pa 10 !Y etq e m-a ues Length of MEAN EMC Area EMC DCGL-EMC Am-241 Evaluation (pCi/g)
(m2)
Area Am-241 Contribution Grid (ft)
Factor a (pCi/g) to SOF 3
34.89 1.00 9.54 213.32 16.357%
5 24.26 2.32 8.36 186.91 12.978%
7 16.54 4.55 7.43 166.08 9.960%
9 11.87 7.53 6.76 151.17 7.851%
11 9.00 11.24 6.27 140.18 6.417%
13 7.09 15.70 5.88 131.54 5.389%
15 5.73 20.90 5.57 124.56 4.600%
17 4.72 26.85 5.31 118.76 3.975%
19 3.95 33.54 5.05 112.92 3.496%
21 3.34 40.97 4.79 107.14 3.116%
23 2.85 49.15 4.57 102.14 2.786%
a EMC Area Factor is based of the area factors contained in the FSS Plan, Section 5.2.6.
r: bl 13 a e A
BS t" LL W. ht d U 235 \\I'. l rea
>PO lO '.Y etq. e a ues Length of M EAN EMC Area EMC DCGL-EMC U-235 Evaluation (pCi/g)
(m2)
Area U-235 Contribution Grid (ft)
Factor a (pCi/g) to SOF 3
3.50 1.00 5.8 24.00 14.57%
5 2.26 2.32 3.84 15.90 14.22%
7 1.47 4.55 2.76 11.42 12.85%
9 1.04 7.53 2.15 8.91 11.65%
11 0.79 11.24 1.82 7.51 10.58%
13 0.64 15.70 1.67 6.91 9.25%
15 0.53 20.90 1.55 6.43 8.23%
17 0.45 26.85 1.46 6.04 7.40%
19 0.38 33.54 1.40 5.78 6.64%
21 0.33 40.97 1.35 5.60 5.94%
23 0.29 49.15 1.32 5.45 5.36%
a EMC Area Factor is based of the area factors contained in the FSS Plan, Section 5.2.6.
NFS North Site-SU6 and SU? Surface Soil Characterization Revision 1 wood.
Page 36 FSS Report Addendum September 2018
T, bl 14 a e A
BS f ll W. ht d Th 232 V, I rea paw lY etg, e a ues Length of EMC DCGL-EMC Th-232 MEAN EMC Area (MOD)
Evaluation (pCi/g)
(m2)
Area Th-232 Contribution Grid (ft)
Factor a (pCi/g) to SOF 3
8.75 1.00 8.4 25.12 34.9%
5 6.28 2.32 4.92 14.71 42.7%
7 4.45 4.55 3.30 9.86 45.1%
9 3.33 7.53 2.48 7.41 44.9%
11 2.61 11.24 1.82 5.43 48.1%
13 2.10 15.70 1.67 4.99 42.0%
15 1.70 20.90 1.55 4.65 36.6%
17 1.38 26.85 1.46 4.37 31.7%
19 1.12 33.54 1.40 4.17 26.9%
21 0.91 40.97 1.35 4.05 22.5%
23 0.73 49.15 1.32 3.94 18.6%
a EMC Area Factor is based of the area factors contained in the FSS Plan, Section 5.2.6.
The SOF contribution from Am-241, U-235, and Th-232 along with the combined SOF values for the area were calculated and provided as Figure 30, and confirms the SOF score for Area B is less than unity (1.0) 1.20 Comparison to SOF Criteria Area-B Combined...
Th-232...
Am-241...
U-235...
1.00 ------------------------
0.80 LL 0 0.60 V,
0.40 0.20 0.00 NFS North Site-1 Figure 30.
SU6 and SU? Surface Soil Characterization Revision 1 10 Area (m 2)
Area B SOF Comparison wood.
Page 37 100 FSS Report Addendum September 2018
To complete the SOF evaluation, the area and SU7 values were combined to ensure the SOF for the entire SU is less than unity, as shown in Table 15.
Table 15.
SUl & Area B SOF Evaluation Length of EMC Area EMC HS-B SUWAA Combined Evaluation (m2)
Area SOF Score SOF Score SOF Score Decision Grid (ft)
Factor a 3
1.00 5.8 65.8%
0.04 0.70 PASS 5
2.32 3.84 69.9%
0.04 0.74 PASS 7
4.55 2.76 67.9%
0.04 0.72 PASS 9
7.53 2.15 64.4%
0.04 0.68 PASS 11 11.24 1.82 65.1%
0.04 0.69 PASS 13 15.70 1.67 56.7%
0.04 0.61 PASS 15 20.90 1.55 49.4%
0.04 0.53 PASS 17 26.85 1.46 43.1%
0.04 0.47 PASS 19 33.54 1.40 37.1%
0.04 0.41 PASS 21 40.97 1.35 31.5%
0.04 0.36 PASS 23 49.15 1.32 26.7%
0.04 0.31 PASS a EMC Area Factor is based of the area factors contained in the FSS Plan, Section 5.2.6.
NFS North Site-SU6 and SU? Surface Soil Characterization Revision 1 wood.
Page 38 FSS Report Addendum September 2018
3 QUALITY CONTROL 3.1 SCANPLor5M Numerous quality control measures were implemented during the surface investigation of SU6 and SU7. The ScanPLot5M push cart platform underwent routine spectral alignment and source response checks (SRCs). Checks include three key control measures to ensure the quality of the data including routine spectral alignments, routine SRCs, and analysis and reporting of K-40 (a naturally-occurring radioactive element).
Spectral alignment was performed at the beginning of each shift of work and throughout the day at least every 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br />. It was performed after any delay or break in survey work. The energy spectrum was aligned so that the K-40 peak and Cesium-137 (Cs-137) peak (from a check source) were within +/- 2 ( +/- <0.5%) channels of their target channels, as established during the commissioning and calibration of each detector.
The detectors were subject to SRCs to a Cs-137 button source on the same or greater frequency as the spectral alignments. The spectrum from the 1-minute SRCs was processed in the same manner as survey data; ROis were analyzed, and net photopeak count rates were calculated. The SRCs were required to be within 20% of the mean or target count rate in order to continue survey activities.
The last quality control measure utilized for the survey was the collection and analysis of the K-40 concentrations throughout the survey units. K-40 analysis provides a number of quality assurance benefits for gamma scanning. K-40 provides a radioactive signal when the real isotopes of interest may not be present in a survey area. Analysis of K-40 can also provide comparisons across different measurements such as scanning, in-situ, and soil sample analysis. The K-40 scanning results are presented graphically in Figure 31 and Figure 32 and are provided to qualitatively demonstrate the sensitivity and spatial resolution produced during the surface scan of SU6 and SU7.
It should be noted that K-40 concentrations vary naturally across many different materials such as soil. rock, and vegetation. Elevated K-40 concentrations are not an indication of contamination or a need for remediation. Changing K-40 concentrations can produce a number of undesirable effects on gross gamma scans such as false positives or improper application of background values.
NFS North Site-SU6 and SU? Surface Soil Characterization Revision 1 wood.
Page 39 FSS Report Addendum September 2018
Figure 31.
Figure 32.
NFS North Site-SU6 and SU? Surface Soil Characterization Revision 1 SU6 K-40 Gamma Map (cps)
SUl K-40 Gamma Map (cps) wood.
Page 40 FSS Report Addendum September 2018
3.2 LABORATORY ANALYSIS Field duplicate samples were collected during both sampling events. The duplicate samples were compared, and the duplicate error ratios (DER) for all samples were less than the established DER control limit value of 2.0.
NFS North Site-SU6 and SU? Surface Soil Characterization Revision 1 wood.
Page 41 FSS Report Addendum September 2018
4 CONCLUSION The surface scans show that the concentrations of the isotopes of concern were uniform across SU6. The in-situ measurements also show that the concentrations of U-235, U-238, Am-241, and Th-232 were stable across the survey unit. The soil samples collected were below the applicable surface DCGL, and the SOFs was less than 1.0. The surface of SU6 meets the established requirements for unrestricted release (NFS, 2006).
The surface scans show that the concentrations of the isotopes of concern were not uniform across SU7. Two areas with elevated gamma radiation levels were identified and investigated.
The in-situ measurements and soil sample results from the corehole samples were below the applicable surface DCGLw, and the SOFs were all less than 1.0. The two elevated areas underwent additional sampling and data analysis. Based on this additional analysis, the two areas designated as A and B do not exceed the DCGLemc, The surface of SU7 meets the established requirements for unrestricted release (NFS, 2006).
NFS North Site-SU6 and SU? Surface Soil Characterization Revision 1 wood.
Page.42 FSS Report Addendum September 2018
5 ACRONYMS Am.............................. americium DCGL......................... derived concentration guideline level DCGLw...................... derived concentration guideline level for the average (or median) concentration in the survey unit DCGLEMc................... elevated measurement comparison concentration guideline level DP............................... Decommissioning Plan DER............................ Duplicate Error Ratio EPA............................. U.S. Environmental Protection Agency FSP............................. Field Sampling Plan FSS............................. Final Status ~urvey ft.................................. foot GPS............................ Global Positioning System L.................................. liter m................................. meter m2............................... square meter mps............................ meters per second NDA........................... non-destructive analysis NFS............................ BWXT Nuclear Fuel Services Inc.
NRC........................... ~ U.S. Nuclear Regulatory Commission pCi/g......................... picocuries per gram Pu............................... plutonium SOF............................ sum of fraction Th................................ thorium U................................. uranium NFS North Site-SU6 and SU? Surface Soil Characterization Revision 1 wood.
Page 43 FSS Report Addendum September 2018
6 REFERENCES AmecFW 2017 NFS North Site Surface Soil Survey Project Field Sampling Plan, Revision 1, October 2017.
ProUCL Version 5.1.
EPA 2016 NFS 2006 Nuclear Fuel Services, Inc., North Site Decommissioning Plan, Revision 3, Nuclear Fuel Services, Inc., Erwin, Tennessee, March 2006.
NFS North Site-SU6 and SU? Surface Soil Characterization Revision 1 wood.
Page 44 FSS Report Addendum September 2018
APPENDIX A Area A and B Sample Locations NFS North Site-SU6 and SU7 Surface Soil Characterization Revision 1 wood.
Page A-1 FSS Report Addendum September 2018
Table A-1.
Sample ID Easting A01-NN33-FS 371245.8598 A02-NE45-FS 371249.0383 A03-EE33-FS 371249.5051
- A04-SE45-FS 371249.4283
- A05-SS33-FS 371246.4833 A06-SW45-FS 371243.5063 A07-WW33-FS 371242.8364 A08-NW45-FS 371243.0766 A09-NW22-F~
371244.4823 Al0-NN15-FS 371246.0136 A10-NN15-FD 371246.0136 All-NE22-FS 371247.5467 A12-EE15-FS 371247.7038 A13-SE22-FS 371247.8609 Al3-SE22-FD 371247.8609 A14-SS15-FS 371246.3295 Al5-SW22-FS 371244.7964 Al5-SW22-FD 371244.7964 Al6-WW15-FS 371244.6393 A17-WW08-FS 371245.3592 Al8-SW10-FS 371245.5294 A19-SS08-FS 371246.2493 A20-SE10-FS 371246.9724 A21-EE08-FS 371246.9822 A22-NE10-FS 371246.8121
. A23-NN08-FS 371246.0922 A24-NW10-FS 371245.3707 A25-NNOO-FS 371246.1711 NFS North Site-SU6 and SU? Surface Soil Characterization Revision 1 Area A Sample Locations Northing 3999564.659 3999564.745 3999561.609 3999558.226 3999558.103 3999557.637 3999561.042 3999564.522 3999562.793 3999562.881 3999562.881 3999563.081 3999561.525 3999559.969 3999559.969 3999559.881 3999559.682 3999559.682 3999561.237 3999561.227 3999560.558 3999560.548 3999560.759 3999561.425 3999562.093 3999562.103 3999562.003 3999561.348 wood.
Page A-2 Date Analyzed Net Weight (g) 2/2/18 282.7 2/2/18 264.2 2/2/18.
323.7 2/2/18 340.6 2/2/18 338.5 2/2/18 296.1 2/2/18 336.5 2/2/18 288.8 2/2/18 345 2/5/18 282.1 2/5/18 303.3.
2/5/18 373.9 2/5/18 293:6 2/5/18 320.1 2/5/18 280.2 2/5/18 318.4 2/6/18 319.9 2/6/18 279.7 2/6/18*
364.2 2/6/18 364.9 2/6/18 360.4 2/6/18 356.4 2/6/18 296.8 2/6/18 292.5 2/6/18 305.2 2/6/18 300.5 2/6/18 282.1 2/6/18 330.6 FSS Report Addendum September 2018
~...,_
- ~-
Table A-2.
Sample ID Easting B01-NN33-FS 371228.3421 B02-NE45-FS 371231.5906 B03-EE33-FS 371231.829 B04-SE45-FS-371231.8309 B05-SS33-FS 371228.649 B06-SW45-FS 371225.4582 B07-WW33-FS 371225.2199 B08-NW45-FS 371225.2179 B09-NW22-FS 371226.9079 B10-NN15-FS 371228.4678 B11-NE22-FS 371230.0234 B11-NE22-FD 371230.0234 B12-EE15-FS 371230.0265 B13-SE22-FS 371230.1409 B14-SS15-FS 371228.5811 B15-SW22-FS 371227.0254 B15-SW22-FD 371227.0254 B16-WW15-FS 371227.0223 B17-WW08-FS 371227.7233 B18-SW10-FS 371227.843 B19-SS08-FS 371228.5546 B20-SE10-FS 371229.2592 B21-EE08-FS 371229.3255 B22-NE10-FS 371229.2058 B23-NN08-FS 371228.4942 B24-NW10-FS 371227.7896 B25-NNOO-FS 371228.5373 NFS North Site-SU6 and SU? Surface Soil Characterization Revision 1 Area B Sample Locations Northing 3999619.239 3999619.244 3999616.076 3999612.899 3999612.662 3999612.66 3999615.828 3999619.005 3999617.445 3999617.447 3999617.561 3999617.561 3999616.008 3999614.459 3999614.456 3999614.343 3999614.3_43 3999615.896 3999615.922 3999615.22 3999615.154
. 3999615.273 3999615.982 3999616.683 3999616.75 3999616.63 3999615.907 wood.
Page A-3 Date Analyzed Net Weight (g) 2/7/18 310.7 2/7/18 371.5 2/7/18 388 2/7/18 334.9 2/7/18-358.6 2/7/18 342.4 2/7/18 369.6 2/7/18 330 2/7/18 336.5 2/7/18 355.4 2/8/18 359.7 2/8/18 366.7 2/8/18 382.1 2/8/18 337.7 2/8/18 320.6 2/8/18 301.1 2/8/18 -
330.4 2/8/18 352.6 2/8/18 361.8 2/8/18 397.6 2/9/18 361.8 2/9/18 332.8 2/9/18 375.1 2/9/18 367.9 2/9/18 385.4 2/9/18 347.5 2/9/18 380.9 FSS Report Addendum September 2018