ML18100A014
| ML18100A014 | |
| Person / Time | |
|---|---|
| Site: | Humboldt Bay |
| Issue date: | 04/04/2018 |
| From: | Bailey E Oak Ridge Institute for Science & Education |
| To: | John Hickman Division of Decommissioning, Uranium Recovery and Waste Programs |
| References | |
| DCN 5272-SR-03-0, RFTA 18-005 | |
| Download: ML18100A014 (34) | |
Text
llJIJ OAK RIDGE INSTITUTE FOR
~I SCIENCE AND EDUCATION
\priJ , _018 t1U1U SS10n afel:) and Safeguard ivi. i n f Decommi sioning, ranium Rec very and Wa te Progra ms Reactor D co1run.i s.ioning Branch Mail t p: TBFS 11545 R ckvill Pike Rockville ID 2 52
SUBJECT:
INDEPENDENT CONFIRMATORY SURVEY
SUMMARY
AND RESULTS FOR SURVEY UNITS OOL10-14 AND NOLOl-09 AT THE HUMBOLDT BAY POWER PLANT, EUREKA, CALIFORNIA (RFTA NO.18-005); DCN 5272-SR-03-0
Dear ~Ir. Hickman:
T he ak Ridge Institute for cieoce and Educatio n (O R] ) is pleased to provide the encl sed final rep rt derailing the independent confirmatory urvey activities of u.rvey units O L 10-14, r mainder of land area (parking lot \ ), and LOl -09, pen land area inside the restricted area (cai *s n), at the Humb ldt Bay Power Plant in E ureka ali~ rnia. This report provides the summary and results of activities performed by Rl E during the period of January 9- 11 2018.
Y u ma contact me at 865.576.6659 if yo u have an y questi n .
inccrcl ,
~ atl! ;g~ Group Iana er fE : lw electr nic di tribution: L. Gersey, N R . Roberts, T. Carter, R D. Hagemeyer, 01 \U File/5272 P.O. Box 117 Oak Ridge, TN 37831
llfj OAK RIDGE INSTITUTE FOR II SCIENCE AND EDUCATION INDEPENDENT CONFIRMATORY SURVEY
SUMMARY
AND RESULTS FOR SURVEY UNITS OOL10-14 AND NOLOl-09 AT THE HUMBOLDT BAY POWER PLANT, EUREKA, CALIFORNIA A. S. Owens and K. M. Engel ORAU FINAL REPORT Prepared for the U.S. Nuclear Regulatory Commission APRIL2018 Further dissemination authorized to NRC only; other requests shall be approved by the originating facility or higher NRC programmatic authority.
ORAU provides innovative scientific and technical solutions to advance research and education, protect public health and the environment and strengthen national security. Through specialized teams of experts, unique laboratory capabilities and access to a consortium of more than 100 major Ph.D.-granting institutions, ORAU works with federal, state, local and commercial customers to advance national priorities and serve the public interest. A 501 (c) (3) nonprofit corporation and federal contractor, ORAU manages the Oak Ridge Institute for Science and Education (ORISE) for the U.S. Department of Energy (DOE). Learn more about ORAU at www.orau.org.
NOTICES The opinions expressed herein do not necessarily reflect the opinions of the sponsoring institutions of Oak Ridge Associated Universities.
This report was prepared as an account of work sponsored by the United States Government.
Neither the United States Government nor the U.S. Department of Energy, nor any of their employees, makes any warranty, expressed or implied, or assumes any legal liability or responsibility for the accuracy, completeness, or usefulness of any information, apparatus, product, or process disclosed, or represents that its use would not infringe on privately owned rights. Reference herein to any specific commercial product, process, or service by trade name, mark, manufacturer, or otherwise, does not necessarily constitute or imply its endorsement or recommendation, or favor by the U.S. Government or any agency thereof. The views and opinions of authors expressed herein do not necessarily state or reflect those of the U.S. Government or any agency thereof.
INDEPENDENT CONFIRMATORY SURVEY
SUMMARY
AND RESULTS FOR SURVEY UNITS OOLl0-14 AND NOL01-09 AT THE HUMBOLDT BAY POWER PLANT, EUREKA, CALIFORNIA FINAL REPORT llrJ OAK RIDGE INSTITUTE FOR II SCIENCE AND EDUCATION Prepared by A. S. Owens and K. M. Engel ORAU APRIL2018 Prepared for the U.S. Nuclear Regulatory Commission Further dissemination authorized to N RC only; o ther reques ts shall be approved by the originating facility or higher NRC programmatic authority.
T his document was prepared for U.S. N uclear Regulatory Commission by the O ak Ridge Institute for Science and E ducation (ORISE) through an interagency agreement with the U.S. D epartment of E nergy (DO E) (NRC FIN N o. F-1244). O RISE is managed by Oak Ridge Associated Universities under D OE contract number D E-SC0014664.
Humboldt Bay Confirmatory Survey Report 5272-SR-03-0
llJJ OAK RIDGE INSTITUTE FOR
~~ SCIENCE AND EDUCATION INDEPENDENT CONFIRMATORY SURVEY
SUMMARY
AND RESULTS FOR SURVEY UNITS OOLl0-14 AND NOLOl-09 AT THE HUMBOLDT BAY POWER PLANT, EUREKA, CALIFORNIA Prepar d by: Date: D 11 II ovl/ 20t~
Prepared by: Date: '-f /'-f /20 I~
Reviewed by: Date:
Dare:
Revi wed bv:
Reviewed and approved for ( 'h --#,.. , Y}
release by: {_../k,/@..)-f /
- E . . Bailey Survey and T c cal Projec1 Group Manager OR.A FINAL REPORT APRIL 2018 Humboldt Ba
- onfi011arory urvey Report 52 2"- R-0' -0
llrJ OAK RIDGE INSTITUTE FOR II SCIENCE AND EDUCATION CONTENTS FIGURES ...... ... ...... ..................................................... .. .................................................................. ................. .. ii TABLES ................ .. .. ...... .... .... ... ... .......................... ... ................................................... .. ... .. ...... .............. .. .........ii ACRONYMS ...................................... ..... ............................................... ........... .. ... ......................................... .iii EXECUTIVE
SUMMARY
... ... .. ... .. ...... .............. ............ ...... .............................................................. ..... ..... ..iv
- 1. INTROD UCTION .... ... .................................. ... .. ...... .... .. ... .............. .......... ... ... ... ...... ... ... ......... .................... 1
- 2. SITE DESCRIPTION .... .... ..... .......... ................... ......... .. ... ....... .. .... ....................... ........ ... .... ... ...... ..... .. ...... 2
- 3. OBJ ECTIVES .................................. .......... :.............. .. ....................... ............. .... ....................................... :... 4
- 4. APPLICABLE SITE GUIDE LINES ............. ...... .............. .......................... ....... .. .. ..................... ..... ........ 4
- 5. PROCE D URES .................. .. .. ........ ............................ ... ....... .... ........................... ................... ... ................... 5 5.1 Surface Scans .......... ... ........................................................................ ................................................. 5 5.2 Soil Sampling.... ... .......................... .................. ... ........................ ...................... .............. ............ ........ 6
- 6. SAMPLE A NALYSIS AND DATA INTERPRETATION .................... ... ............. .... .. .. .... ................. 6
- 7. FINDINGS AND RESULTS .................. .................................................. ........ ....... ... .... .. ............ ............. 6 7 .1 Surface Scans ... ........................ ......................................................................... ...... ............................ 6 7.2 Radionuclide Concentrations in Soil ...................... ... .............. ... .. ........ ............. .................... .. .. .. ... 8
- 8.
SUMMARY
............. .... .. .. .. ..... ...... .. ............... ............. .. ............. ............... .......... .. ...... ..... ...... .. ........ ....... ........ 9
- 9. REFERENCES .. .............. .... .. .. .................... .~................... ....... ............ ................................... .......... .... ...... 10 APPENDIX A: FIGURES APPENDIXB: D ATA TABLES APPENDIX C: SURVEY AND A NALYTICAL PROCED URES APPENDIX D : MAJOR INSTRUMENTATION Humboldt Bay Confirmatory Survey Report 5272-SR-03-0
l1JJ OAK RIDGE INSTITUTE FOR II SCIENCE AND EDUCATION FIGU RES Figure 2.1. HBPP Aerial View ................... ... ................................................................................................... 2 Figure 2.2. Approximate Locations of SUs OOL10-14 and NOLOl-09 ................................................... 3 TABLES Table 4.1. HBPP Soil DCGLs for SU OOL10-14, Scaled to 23.07 mrem/y .......................................... .4 Table 4.2. HBPP Soil DCGLs for SU NOLOl-09, Scaled to 23.58 mrem/yr .......... ................................ 5 Table 7.1. Summary of Survey Scan Data .. .............. ...................................................................................... 7 Table 7.2. Soil Sample Information ........... ..................................................... ................................................. 8 Table 7.3. Summary of Soil Sample Results ............ ................................ ........................................ ............... 8 Humboldt Bay Confirmatory Survey Report u 5272-SR-03-0
llfj OAK RIDGE INSTITUTE FOR II SCIENCE AND EDUCATION ACRONYMS AEC Atomic Energy Commission cpm counts per minute DCGL derived concentration guideline levels DOE U.S. Department of Energy GPS Global positioning system HBPP Humboldt Bay Power Plant HBRP Humboldt Bay Repowering Project MDC minimum detectable concentration NaI sodium iodide NIST National Institute of Standards and Technology NRC U.S. Nuclear Regulatory Commission ORISE Oak Ridge Institute for Science and Education pCi/g p1cocunes per gram PG&E Pacific Gas & Electric Company Q-plot quantile plot ROC radionuclide of concern SAFSTOR safety storage SOP sum-of-fractions SU survey unit TAP total absorption peak Humboldt Bay Confirmatory Survey Report ill 5272-SR-03-0
llrJ OAK RIDGE INSTITUTE FOR II SCIENCE AND EDUCATION INDEPENDENT CONFIRMATORY SURVEY
SUMMARY
AND RESULTS FOR SURVEY UNITS OOLl0-14 AND NOLOl-09 AT THE HUMBOLDT BAY POWER PLANT, EUREKA, CALIFORNIA EXECUTIVE
SUMMARY
T he U.S. N uclear Regulatory Commission (NRC) requested that the Oak Ridge Institute for Science and Education (ORISE) perform an independent confirmatory survey at the Humboldt Bay Power Plant in Eureka, California. Pacific Gas and Electric Company, who owns and operates the site, is currently engaged in the decontamination and decommissioning of the Unit 3 boiling water nuclear reactor, along with the impacted areas associated with its operation. This report focuses on confirmatory survey activities performed in survey units OOL10-14, remainder o f land area (parking lot A), and NOL01-09, open land area inside the restricted area (caisson).
ORISE performed independent assessment activities, including gamma walkover surveys and soil sampling, during the period of January 9-11 , 2018. Confirmatory survey activities included high-density gamma walkover surveys of accessible areas of survey units OOL10-14 and NOL01-09 and the collection of three split soil samples. O RISE's gamma survey results, combined with laboratory analytical results from the soil samples, support the conclusion that survey units OOL1 0-14 and NOL01-09 satisfy the NRC-approved soil derived concentration guideline levels described in the site's final status survey documents.
Humboldt Bay Confirmatory Survey Report lV 5272-SR-03-0
l1rJ OAK RIDGE INSTITUTE FOR Ii SCIENCE AND EDUCATION INDEPENDENT CONFIRMATORY SURVEY
SUMMARY
AND RESULTS FOR SURVEY UNITS OOL10-14 AND NOLOl-09 AT THE HUMBOLDT BAY POWER PLANT, EUREKA, CALIFORNIA
- 1. INTRODUCTION The Pacific Gas & E lectric Company (PG&E) operated the Humboldt Bay Power Plant (HBPP)
Unit 3 nuclear reactor near Eureka, California under Atomic Energy Commission (AEC) provisional license number DPR-7. HBPP Unit 3 achieved initial criticality in February 1963 and began commercial operations in August 1963. Unit 3 was a natural circulation boiling water reactor with a direct-cycle design. Stainless steel fuel claddings were used from startup until cladding failures resulted in plant system contamination-zircaloy-clad fuel was used exclusively starting in 1965, eliminating cladding-related contamination. A number of spills and gaseous releases were reported during operations, resulting in a range of mitigation activities (ESI 2008).
In July 1973, Unit 3 was shut down for annual refueling and seismic modifications. However, by December 1980, it was concluded that completing the required upgrades and restarting Unit 3 would be cost prohibitive. PG&E decided in June 1983 to decommission Unit 3, received a possession-only license amendment, and placed the unit into cold shutdown and safety storage (SAFSTOR). The impacted areas associated with Unit 3 are currently undergoing decommissioning.
As part of the Humboldt Bay Repowering Project (HBRP), PG&E has built ten new fossil fuel units (16.3 MWe [megawatt electric] each) on the site in the vicinity of Unit 3. Decommissioning activities have also been completed on the adjacent fossil fuel Units 1 and 2, with all materials being removed to ground level (ESI 2008).
The U.S. Nuclear Regulatory Commission (NRC) requested that the Oak Ridge Institute for Science and Education (ORISE) perform confirmatory surveys of survey units (SU) OOL10-14, open land area inside the restricted area (caisson), NOLOl-09, remainder of land area (parking lot A), and OOL10-15, Buhne Slough. ORISE performed the confirmatory surveys on January 9-11 , 2018, with the exception of SU OOL10-15, which was inaccessible due to standing water and was not surveyed.
Humboldt Bay Confirmatory Survey Report 1 5272-SR-03-0
llrJ OAK RIDGE INSTITUTE FOR II SCIENCE AND EDUCATION
- 2. SITE DESCRIPTION The HEPP site, owned by PG&E, consists of 143 acres on the southern edge of Humboldt Bay, four miles southwest of the town of Eureka, in Humboldt County, California. Figure 2.1 provides an aerial view of the HEPP. PG&E maintains ten new operating electric generating units at the HEPP site (in the New Generation Footprint Area) that run on fossil fuels, two non-operating fossil fuel units (Units 1 and 2), and one non-operational nuclear unit (Unit 30). Units 1 and 2, which were decommissioned to ground level, were interconnected with and west of Unit 3 (ESI 2008). The remaining property includes mostly open areas and protected wetlands.
Figure 2.1. H BPP Aerial View Humboldt Bay Confirmatory Survey Report 2 5272-SR-03-0
llrJ OAK RIDGE INSTITUTE FOR II SCIENCE AND EDUCATION This report focuses on SUs OOLl0-14 and NOLOl-09. SU OOLl0-14 encompasses the remainder of the land area (parking lot A). It is an open-land area comprised of soil and gravel and consists of approximately 6,800 square meters (m2) o f land that was formerly a plant site parking lot. During the time of the survey, the majority o f the SU was too muddy to traverse. SU NOLOl -09 is the open-land area inside the RA (the caisson). The land area of the caisson is approximately 24 meters below grade and consists of 884 m 2 of sandy soil. Figure 2.2 provides the approximate location of SUs OOLl0-14 and NOLOl-09.
OO L 10-14 Parking Lot A "'
t Cre a1e<I by: A.. JOs-ahl..... n .... , Marc.h 2S,20ll Figure 2.2. Approximate Locations ofSUs OOL10-14 and NOLOl-09 Humboldt Bay Confirmatory Survey Report 3 5272-SR-03-0
l1fj
~I OAK RIDGE INSTITUTE FOR SCIENCE AND EDUCATION
- 3. OBJECTIVES The objectives of the confirmatory survey activities were to generate independent radiological data for use by the NRC in evaluating the accuracy and adequacy of the licensee's procedures and results.
- 4. APPLICABLE SITE GUIDELINES T he primary radionuclides of concern (ROCs) identified for the SUs are beta-gamma emitters-fission and activation products-resulting from reactor operation. T he HBPP derived concentration guideline levels (DCGLs) for soils are presented in Tables 4.1 and 4.2. For SU OOLl0-14, previous characterization has shown that not all of the site-sp cific radionuclides would be present, and the following ROCs were deselected from the analysis: C-14, Ni-59, Ni-63, Tc-99, Pu-238, Pu-239/240, Pu-241, Cm-243, Cm-244, Cm-245, Cm-246, and Sr-90. T he resultant dose from these ROCs was 1.93 mrem/y and the DCGLs were scaled to 23.07 mrem/y (fable 4.1) (PGE 2016). For SU NOLOl-09, the caisson wall will remain in the ground at the time of license termination, and, since the wall contains soils from the area, a dose contribution from the soils in the wall was established and used to scale the DCGLs. The soils were determined to contribute a dose of 1.42 mrem/y, and the D CGLs were scaled to 23.58 mrem/y (fable 4.2) (PGE 2017).
Table 4.1. HBPP Soil DCGLs for SU OOLto-14, Scaled to 23.07 mrem/y ROC DCGL (pCi/ g)* ROC DCGL (pCi/ g)
Am-241 23.07 E u-154 8.67 Co-60 3.51 H -3 627.42 Cs- 137 7.29 Nb-94 6.55 E u-152 9.23 Np-237 1.01
- pCi/g = picocu,~cs per gram Humboldt Bay Confirmatory Survey Report 4 5272-SR-03-0
llrJ OAK RIDGE INSTITUTE FOR II SCIENCE AND EDUCATION Table 4.2. HBPP Soil DCGLs for SU NOL01-09, Scaled to 23.58 mrem/yr DCGL DCGL DCGL ROC ROC ROC (pCi/g)a (pCi/g) (pCi/g)
Am-241 23.6 Cs-137 7.45 N p-237 1.04 C-14 6.3 E u-152 9.43 Pu-238 29 Cm-243 29 Eu-154 8.87 Pu-239 26 Cm-244 48 H -3 680 Pu-240 26 Cm-245 17 Nb-94 6. 7 Pu-241 860 Cm-246 25 Ni-59 1,900 Sr-90 1.5 Co-60 3.58 Ni-63 720 Tc-99 12 a pC1/ g = p1cocunes per gram For consistency with the licensee's application of D CGLs to gross soil concentrations such that data were not corrected for background contributions, ORISE also reported data results without background corrections. T he sum-of-fractions (SOP) approach was used to demonstrate compliance with the dose limit. SOP calculations were performed as follows :
SOFTOTAL = In
- -o J-SOFj =
I (.
n j=O DCG~ .
W ,J Where Ciis the concentration of ROC "j," and DCG~v.i is the DCG~v for ROC " j." Note that gross concentrations were considered here for conservatism.
- 5. PROCEDURES T he confirmatory survey activities were conducted during the period of January 9-11, 2018, in accordance with the project-specific confirmatory survey plan, the ORAU Radiological and Environmental Survry Procedure Manual, and the ORAU Environmental Services and Radiation Training Qualiry Program Manual (ORISE 2016, ORAU 2016a and 2016b).
5.1 SURFACE SCANS O RISE performed high-density gamma radiation scans of the accessible soil surfaces in SU OOL10-14 and NOL01-09. Gamma scans were performed using a Ludlum Model 44-10 sodium iodide (Nal) detector coupled to a Ludlum Model 2221 ratemeter-scaler with audible indicator.
Humboldt Bay Confirmatory Survey Report 5 5272-SR-03-0
_J
llrJ OAK RIDGE INSTITUTE FOR II SCIENCE AND EDUCATION Additionally, for the survey of SU OOL10-14, the gamma detector/ratemeter was coupled to a global positioning system (GPS) that enabled real-time gamma count rate and spatial data capture.
GPS spatial data could not be captured by ORISE in SU NOL01-09 because the caisson walls were restricting satellite acquisition. However, the gamma data was logged without the GPS coordinate information. The ORISE survey team was listening to the audible signal during the walkover surveys and areas with elevated radiation levels were marked with flags for further investigation.
5.2 SOIL SAMPLING Surface soil samples (0-15 cm in depth) were collected from three locations within SU NOL01-09 based on the results from the gamma scans. At the NRC's request, the soil samples were split during sample collection with the site. At each of the three locations, the soil was placed into a metal bowl and homogenized before ORISE and the site collected individual samples.
- 6. SAMPLE ANALYSIS AND DATA INTERPRETATION Samples and data collected on site were returned to the ORISE facility for analysis and interpretation. Sample custody was transferred to the Radiological and E nvironmental Analytical Laboratory (REAL) in Oak Ridge, Tennessee. Sample analyses were performed in accordance with the ORAU Radiological and EnvironmentalAna!Jtical Laboratory Procedures Manual (ORAU 2017). Soil samples were analyzed for all ROCs using gamma spectroscopy, alpha spectroscopy, liquid scintillation counting, and low background proportional counting. The REAL does not have a procedure for the analysis for Ni-59; therefore, analysis for Ni-59 was performed by a subcontracted laboratory at the direction and approval of the NRC. Aliquots from each soil sample were portioned out by the REAL staff and sent to the subcontracted laboratory under chain of custody for analysis.
All results were reported in units of picocuries per gram (pCi/ g).
- 7. FINDINGS AND RESULTS The results of the confirmatory survey are discussed in the subsections below.
7.1 SURFACE SCANS During survey activities in SU OOL10-14, only a limited portion of the SU was accessible due to slippery/muddy conditions. As a result, ORISE was only able to survey the eastern-most portion of Humboldt Bay Confirmatory Survey Report 6 5272-SR-03-0
llrJ OAK RIDGE INSTITUTE FOR II SCIENCE AND EDUCATION the SU. The confirmatory gamma scan results of SU OOL10-14 exhibited radiation levels within the detector background range. Scans did not identify any areas for further investigation. Figure A-1 provides the results of the gamma walkover survey. ORJSE would like to note that the background map used in Figure A-1 is from November 2015 and does not depict the conditions of the survey unit during the survey (i.e., the paved parking lot was removed and the area was soil and vegetation).
The confirmatory gamma scan results of SU NOLOl-09 exhibited radiation levels within the detector background range except in three locations. Sample 5272S0021 was collected near the south wall of the caisson between the southeast and southwest pumps, was discrete in area, and clearly above background. After the soil sample was collected, the post-sample count was similar to background counts for the area. It is hypothesized that a small, discrete item was causing the elevated count rate and not homogeneous soil contamination. Sample 5272S0022 was collected in the southwest quadrant of the caisson, count rates were elevated, spread over an area, and were slightly above background (pre-sample count was 600 counts per minute [cpm] above the average cpm value for the area) . Sample 5272S0023 was collected from the northeast side of the northeast pump within the caisson and the higher gamma counts were believed to be due to soil inside the pump casing and not the surrounding soil. See the discussion in Section 7 .2.
Table 7.1 provides a summary of all the scan data. Appendix A provides more details on the data collected in SU NOLOl-09.
Table 7.1. Summary of Survey Scan Data Nal (cpm)
Survey Unit Minimum Maximum Mean OOL10-14 3,700 7,000 5,100 NOL01-09 (Excluding NE Pump) 4,300 9,200 5,400 NOL01-09 NE Pump 4,800 9,500 6,200 Since GPS satellites could not be acquired by ORJSE during the survey of SU NOLOl-09 to plot a gamma walkover map, the logged data were graphed in a quantile plot (Q-plot) (Figure A-2). T he Q-plot of the data shows an identifiable step-up o f the data, which typically is indicative of residual contamination. Areas with elevated levels of radiation were marked for judgmental soil sampling.
Table 7 .2 provides details of the soil samples. Figure A-3 shows the location of the soil samples Humboldt Bay Confirmatory Survey Report 7 5272-SR-03-0
llrJ OAK RIDGE INSTITUTE FOR II SCIENCE AND EDUCATION collected from inside the caisson. The sample coordinates were provided to ORISE by the licensee who used a Trimble Total Station to acquire satellites during their survey and sampling activities.
ORISE Sample ID Easting Northing Height cpm 5272S0021 5949408.37 2161066.36 -74.64 12,000 5,400 5272S0022 5949372.41 2161090.25 -76.83 6,000 5,700 5272S0023 5349434.22 2161161.02 -77. 66 8,800 10,000 7 .2 RADIONUCLIDE CONCEN TRATIONS IN S OIL Analytical results for the soil samples collected from SU NOLOl-09 are provided in Table B.1. All Cm-246 alpha decays with an energy that cannot be resolved from that of the Am-243 tracer and Am-241 when performing alpha spectroscopy. If Cm-246 were present in the samples, the analysis would be expected to show an elevated tracer yield and/or a statistically positive Am-241 quantity.
Neither of those conditions were seen in the analytical data, and each of the alpha spectrum results was reviewed by laboratory staff who concluded there was no evidence to suggest that Cm-246 is present in the any of the samples. Table 7 .3 provides a summary of the SOF results.
Sample 5272S0023 was taken from an area outside of the NE pump casing where the counts were higher than the surrounding area. As previously stated, ORISE believes the higher gamma counts were due to soil inside the pump casing and not the surrounding soil. The analytical results from this sample show that it had the lowest SOF of any of the samples and does not indicate there is contamination within the soil outside the pump casing. The higher gamma counts are most likely from soil within the NE pump, which was not sampled by ORISE.
Humboldt Bay Confirmatory Survey Report 8 5272-SR-03-0
llrJ OAK RIDGE INSTITUTE FOR II SCIENCE AND EDUCATION 8.
SUMMARY
At the NRC's request, ORISE conducted confirmatory survey activities of SUs OOL10-14 and NOL01-09 at the HBPP during the period of January 9-11, 2018. The survey activities included gamma surface scans, gamma radiation measurements, and soil sampling.
The gamma walkover surface scans of SU OOL10-14 were not distinguishable from background; therefore, no soil samples were collected in this area. The gamma walkover surface scans of SU NOL01-09 identified three areas with elevated radiation; therefore, three soils samples were collected within the SU. The soil samples collected from within SU NOL01-09 contained concentrations of RO Cs that were below the DCGLs. The results support the conclusion that the SUs OOL10-14 and NOL01-09 satisfy the NRC-approved soil DCGLs described in the site's final status survey documents.
Humboldt Bay Confirmatory Survey Report 9 5272-SR-03-0
llfJ OAK RIDGE INSTITUTE FOR II SCIENCE AND EDUCATION
- 9. REFERENCES ESI 2008 . Historical Site Assessment. Draft. Prepared for the Humboldt Bay Power Plant Pacific Gas
& Electric Company. Eureka, California. September.
ORAU 2014. ORAU Radiation Protedion Manual. Oak Ridge Associated Universities. Oak Ridge, Tennessee. October.
ORA 2016a. ORAU Radiological and Environmental Survry Procedures Manual. Oak Ridge Associated Universities. Oak Ridge, Tennessee. November 10.
ORAU 2016b. ORAU E nvironmental Services and Radiation Training Qualify Program Manual. Oak Ridge Associated Universities. Oak Ridge, Tennessee. November 9.
ORAU 2016c. ORAU Health and Sajefy Manual. Oak Ridge Associated U niversities. Oak Ridge, Tennessee. January.
ORAU 2017. ORAU Radiological and Environmenta/ Ana/ytica/ Laboratory Procedures Manual. Oak Ridge Associated U niversities. Oak Ridge, Tennessee. August 24.
ORISE 2016. Prqject-specific Plan far the Confirmatory Survry Attivities at the Humboldt Btry Power Plant Eureka, California. DCN 5272-PL-02-0. Oak Ridge Associated Universities. Oak Ridge, Tennessee. August 3.
PGE 2016. Final Status Survry Planning (FSSP) Worksheet-OOL10-14. Rev. 2B. RCP FSS-2, Att. 9.1.
Pacific Gas & Electric Company. San Francisco, California. November 2.
PGE 2017. Final Status Survry Planning (FSSP) Worksheet-NOL01-09, Rev. 2B. RCP FSS-2, Att. 9.1.
Pacific Gas & Electric Company. San Francisco, California. November 29.
Humboldt Bay Confirmatory Survey Report 10 5272-SR-03-0
APPENDIX A: FIGURES Humboldt Bay Confirmatory Survey Report 5272-SR-03-0
6351 -6 972 -
5901 - 6350 -
5451 -5900 -
4551 - 5000 - - OOL 10-14 Parking Lot A 4101 -4550
<4100 OOL 10-15 Buhne Slough 0 8 16 II ORISE Cr:cucdl by: A.~ th.link Parking Lot A Gamma Walkover Dllre:: !.larch 2S, 201.S.
MHe.n Figure A-1. Gamma Walkover Survey of SU OOL10-14 Humboldt Bay Confirmatory Survey Report A -1 5272-SR-03-0
Nat Scans for SU NOL01-09 Caisson B800 8000 5600 4800
-3 -2 *1 0 l Theoretical Quantiles (Standard Normal)
Figure A-2. Q-Plot for SU NOLOl-09 Survey Data Humboldt Bay Confirmatory Survey Report .A-2 5272-SR-03-0
5 250022 Figure A-3. Approximate Soil Sample Locations in SU NOLOl-09 H umboldt Bay Confirmatory Survey Report A-3 5272-SR-03-0
APPENDIX B: DATA TABLES Humboldt Bay Confirmatory Survey Report 5272-SR-03-0
I Table B.1. ORI SE Soil Sample Results (pCi/ g) 5272S0021 5272S0022 5272S0023 ROC Concentration MDC Concentration MDC Concentration MDC Am-241 0.0081 +/- 0.0080 0.0060 0.016 +/- 0.011 0.006 0.001 9 +/- 0.0037 0.0057 C-14 0.35 +/- 0.83 1.41 0. 76 +/- 0.85 1.42 -0.53 +/- 0.86* 1. 51 Cm-243/ 244 0.0020 +/- 0.0040 0.0060 -0.0019 +/- 0.0038 0.0186 -0.0019 +/- 0.0037 0.0182 Cm-245 0.023 +/- 0.068 0.164 0.001 +/- 0.044 0.138 0.027 +/- 0.079 0.188 Co-60 0.130 +/- 0.028 0.039 0.562 +/- 0.047 0.024 0.010 +/- 0.011 0.028 Cs-137 0.048 +/- 0.016 0.029 0.190 +/- 0.024 0.029 0.051 +/- 0.013 0.022 E u-152 0.000 +/- 0.035 0.076 0.008 +/- 0.027 0.064 -0.009 +/- 0.029 0.067 E u-154 -0.091 +/- 0.077 0.144 0.013 +/- 0.045 0.129 -0.007 +/- 0.033 0.103 H -3 0.88 +/- 0.98 1.64 0.31 +/- 0.96 1.65 10.3 +/- 1.5 1.8 Nb-94 -0.007 +/- 0.015 0.031 0.003 +/- 0.014 0.029 -0.002 +/- 0.010 0.022 Ni-59 -9.93 +/- 7.21 11.1 1.51 +/- 6.31 12.7 0.00 +/- 4.12 3.28 Ni-63 0.37 +/- 0.42 0. 71 0.89 +/- 0.42 0.68 0.58 +/- 0.43 0. 71 N p-23 7 0.0078 +/- 0.0076 0.0058 0.000 +/- 0.0040 0.0061 0.0041 +/- 0.0080 0.0196 Pu-238 0.01 7 +/- 0.011 0.006 0.027 +/- 0.015 0.006 0.016 +/- 0.011 0.006 Pu-239/ 240 0.0058 +/- 0.0066 0.0058 0.014 +/- 0.011 0.006 0.0061 +/- 0.0090 0.0196 Pu-241 0.8 +/- 1.9 3.2 -0.6 +/- 1.9 3.4 1.7 +/- 2.1 3.5 Sr-90 -0.06 +/- 0.16 0.31 0.07 +/- 0.17 0.30 -0.06 +/- 0.17 0.32 Tc-99 0.05 +/- 0.47 0.83 -0.07 +/- 0.48 0.85 -0.09 +/- 0.47 0.83 SOF* 0.12 0.36 0.03
'The SOFs were calculated using the most conservative DCGL for Cm-243 / 244 and Pu-239/ 240.
Humboldt Bay Confirmatory Survey Report B-1 5272-SR-03-0
APPENDIX C: SURVEY AND ANALYTICAL PROCEDURES Humboldt Bay Confirmatory Survey Report 5272-SR-03-0
C.1. PROJECT HEALTH AND SAFETY ORISE performed all survey activities in accordance with the ORAU Radiation Protection Manual, the ORAU Health and Sefe!J Manual, and the ORAU Radiological and Environmental Survry Procedures Manual (ORAU 2014, ORAU 2016c, and ORAU 2016a). Prior to on-site activities, a work-specific hazard checklist was completed for the project and discussed with field personnel. The planned activities were thoroughly discussed with site personnel prior to implementation to identify hazards present.
Additionally, prior to performing work, a pre-job briefing and walkdown of the survey areas were completed with field personnel to identify hazards present and discuss safety concerns. Should ORISE have identified a hazard not covered in the ORAU Radiological and Environmental Survry Procedures Manual (ORAU 2016a) or the project's work-specific hazard checklist for the planned survey and sampling procedures, work would not have been initiated or continued until the hazard was addressed by an appropriate job hazard analysis and hazard controls.
C.2. CALIBRATION AND QUALITY ASSURANCE Calibration of all field instrumentation was based on standards/ sources, traceable to National Institute of Standards and Technology (NIST).
Field survey activities were conducted in accordance with procedures from the following documents:
- ORAU Radiological and Environmental Survry Procedures Manual (ORAU 2016a)
- ORAU Radiological and EnvironmentalAna!Jtical Laboratory Procedures Manual (ORAU 2017)
- ORAU Environmental Services and Radiation TrainingQuali!J Program Manual (ORAU 2016b)
The procedures contained in these manuals were developed to meet the requirements of U.S. Department of Energy (DOE) Order 414.lD and the NRC Quality A ssurance Manual for the Office ofNuclear Material Sefe!J and Sefeguards and contain measures to assess processes during their performance.
Humboldt Bay Confirmatory Survey Report C-1 5272-SR-03-0
Quality control procedures include:
- Daily instrument background and check-source measurements to confirm that equipment operation is within acceptable statistical fluctuations.
- Participation in Mixed-Analyte Performance Evaluation Program and Intercomparison Testing Program laboratory quality assurance programs.
- Training and certification of all individuals performing procedures.
- Periodic internal and external audits.
C.3. SURVEY PROCEDURES C.3.1 SURFACE SCANS Scans for elevated gamma radiation were performed by passing the detector slowly over the surface.
The distance between the detector and surface was maintained at a minimum. Specific scan minimum detectable concentrations (MDCs) for the NaI scintillation detectors were not determined as the instruments were used solely as a qualitative means to identify elevated gamma radiation levels in excess of background. Identifications of elevated radiation levels that could exceed the site criteria were determined based on an increase in the audible signal from the indicating instrument.
C.3.2 SOIL SAMPLING Soil samples were collected using a clean shovel to transfer soil into a clean metal bowl for homogenization. The soil was thoroughly homogenized before the sample (approximately 0.5 kg) was transferred to a new sample container using a clean garden trowel by ORISE personnel. In total, ORISE collected three soil samples during the confirmatory survey, labeled each sample in accordance with survey procedures (ORAU 2016a), and completed the required custody documentation.
C.4. RADIOLOGICAL ANALYSIS C.4.1 GAMMA SPECTROSCOPY Samples were analyzed as received, mixed, crushed, and/ or homogenized as necessary, and a portion sealed in a 0.5-liter Marinelli beaker. The quantity placed in the beaker was chosen to reproduce the calibrated counting geometry. Net material weights were determined and the samples counted using Humboldt Bay Confirmatory Survey Report C-2 5272-SR-03-0
intrinsic, high purity, germanium detectors coupled to a pulse height analyzer system. Background and Compton stripping, peak search, peak identification, and concentration calculations were performed using the computer capabilities inherent in the analyzer system. All total absorption peaks (TAPs) associated with the ROCs were reviewed for consistency of activity. Spectra were also reviewed for other identifiable TAPs. TAPs used for determining the activities of ROCs and the typical associated MDCs for a one-hour count time are presented in Table C.1.
Table C.1. Typical MDCs Total Absorption Peak Radionuclide TAP(MeV)* MDC (pCi/g)
Co-60 1.332 0.06 Cs-137 0.662 0.05 Eu-152 0.344 0. 10 Eu-154 0.723 0. 15 Nb-94 0.871 0.05 Cm-245 0.175 0.2 Am-241 0.0595 0.15 a mega electron volt C.4.2 ALPHA SPECTROSCOPY Samples were homogenized and dissolved by a combination of potassium hydrogen fluoride and pyrosulfate fusions. The fusion cakes were dissolved, and all alpha emitters are co-precipitated on barium sulfate. The barium sulfate is re-dissolved and the contaminant of concern was separated from the other actinides by extraction chromatography utilizing Eichrom Technologies resins, co-precipitated with cerium fluoride, and analyzed using passivated implanted planar silicon detectors, alpha spectrometers, and multichannel analyzers. The alpha spectroscopy detector system calculates an MDC for each individual isotope per sample based on the detector background, counting efficiency, chemical yield, and sample quantity. TAPs used for determining the activities of ROCs and the typical associated MDCs for a one-hour count time are shown in Table C.2.
Humboldt Bay Confirmatory Survey Report C-3 5272-SR-03-0
Table C.2. MDC Derived from Total Absorption Peak Radionuclide TAP(MeV) MDC (pCi/g)
Am-241 5.486 0.05 Pu-238 5.499 0.04 Pu-239/240 5.155 0.02 Cm-243 / Cm-244 5.805 0.02 Cm-246 5.386 0.05 Np-237 4.788 0.08 C.4.3 Tc-99 ANALYSIS Tc-99 was quantified by radiochemical separation using extraction chromatography and counted by liquid scintillation. Samples were homogenized and leached with dilute nitric acid. The leachates were passed through an ex traction chromatographic column containing a resin (TEVA) highly specific for technetium in the pertechnatate form. T he technetium is absorbed onto the extraction resin. T he resin is added to a scintillation vial containing an appropriate cocktail and counted using a liquid scintillation analyzer. All interfering beta-emitting radionuclides are effectively removed (including C-14, P-32, S-35, Sr-90, Y-90, and T h-234) using TEVA resin under the conditions in this procedure. The typical MDC for a 60-minute count time using this procedure is 0.8 pCi/ g.
C.4.4 PU-241 ANALYSIS Once steps outlined in C.4.2 for analysis by alpha spectroscopy are completed, the sample is added to a scintillation vial containing an appropriate cocktail and counted for Pu-241 using a liquid scintillation analyzer. The typical MDC for a 60-minute count time using this procedure is 3.4 pCi/ g.
C.4.5 NI-63 ANALYSIS Soil samples were spiked with a nickel carrier and digested with a mixture of nitric and hydrochloric acids. Unwanted elements, such as iron and cobalt, are then removed by running the slurry via anion exchange chromatography. Nickel is then separated from the slurry using a nickel selective resin cartridge. Nickel is then eluted off of the column with a dilute nitric acid solution. Ni-63 activity is then determined via liquid scintillation counting. The typical MDC for a 60-minute count time using this procedure is 0.8 pCi/ g.
Humboldt Bay Confirmatory Survey Report C-4 5272-SR-03-0
C.4.6 RADIOACTIVE STRONTIUM ANALYSIS Sr-90 concentrations were quantified by total sample dissolution followed by radiochemical separation and counted on a low background proportional counter. Samples were homogenized and dissolved by a combination of potassium hydrogen fluoride and pyrosulfate fusions. The fusion cakes were dissolved, and strontium is coprecipitated on lead sulfate. The strontium was separated from residual calcium and lead by reprecipitating strontium sulfate from EDTA at a pH of 4.0.
Strontium was separated from barium by complexing the strontium in DTPA while precipitating barium as barium chromate. The strontium was ultimately converted to strontium carbonate and counted on a low-background gas proportional counter. The typical MDC for a 60-minute count time using this procedure is 0.4 pCi/ g.
C.4.7 C-14AND H-3ANALYSES C-14 and H-3 analyses were performed using a material oxidizer and counted by liquid scintillation.
The Material Oxidizer combusts soil samples in a stream of oxygen gas and passes the products through a series of catalysts. The C-14 and H-3 are then captured in a trapping scintillation cocktail specific to that radionuclide. Typical MDCs for C-14 and H -3 for a 60-minute count time using this procedure are 2.5 pCi/ g and 2.0 pCi/ g, respectively.
C.4.8 D ETECTION LIMITS Detection limits, referred to as MDCs, were based on 95% confidence level. Because of variations in background levels, measurement efficiencies, and contributions from other radionuclides in samples, the detection limits differ from sample to sample and instrument to instrument.
Humboldt Bay Confirmatory Survey Report C-5 5272-SR-03-0
APPENDIX D: MAJOR INSTRUMENTATION Humboldt Bay Confirmatory Survey Report 5272-SR-03-0
The display of a specific product is not to be construed as an endorsement of the product or its manufacturer by the author or his employer.
D.1. SCANNING AND MEASUREMENT INSTRUMENT/
DETECTOR COMBINATIONS D.1.1 GAMMA Ludlum Nal Scintillation Detector Model 44-10, Crystal: 5.1 cm X 5.1 cm coupled to: Ludlum Ratemeter-scaler Model 2221 coupled to: Trimble Geo 7X D.2. LABORATORY ANALYTICAL INSTRUMENTATION High-Purity, Extended Range Intrinsic Detector CANBERRA/Tennelec Model No: ERVDS30-25195 (Canberra, Meriden, Connecticut)
Used in conjunction with:
Lead Shield Model G-11 (Nuclear Lead, Oak Ridge, Tennessee) and Multichannel Analyzer Canberra's Gamma Software Dell Workstation (Canberra, Meriden, Connecticut)
High-Purity, Intrinsic Detector EG&G ORTEC Model No. GMX-45200-5 Used in conjunction with:
Lead Shield Model G-11 Lead Shield Model SPG-16-K8 (Nuclear Data)
Multichannel Analyzer Canberra's Gamma Software Dell Workstation (Canberra, Meriden, Connecticut)
High-Purity, Intrinsic Detector EG&G ORTEC Model No. GMX-30P4 Used in conjunction with:
Lead Shield Model G-11 Lead Shield Model SPG-16-K8 (Nuclear Data)
Multichannel Analyzer Canberra's Gamma Software Dell Workstation (Canberra, Meriden, Connecticut)
Humboldt Bay Confirmatory Survey Report D -1 5272-SR-03-0
High-Purity, Intrinsic Detector EG&G ORTEC Model No. CDG-SV-76/GEM-MX5970-S Used in conjunction with:
Lead Shield Model G-11 Lead Shield Model SPG-16-K8 (Nuclear Data)
Multichannel Analyzer Canberra's Gamma Software Dell Workstation (Canberra, Meriden, Connecticut)
Alpha Spectrometry System Canberra Model: Alpha Analyst (Canberra, Meriden, CT)
Used in conjunction with:
Alpha Spectrometer Apex Alpha Software Dell Workstation (Canberra, Meriden,CT)
Low-Background Gas Proportional Counter Series 5 XLB (Canberra, Meriden, CT)
Used in conjunction with:
Eclipse Software Dell Workstation (Canberra, Meriden,CT)
Liquid Scintillation Analyzer Perkin Elmer Model Tri-Carb 5100 TR (Perkin Elmer, Shelton, CT)
Used in conjunction with:
Quantamart Software Perkin Elmer, Shelton, CT)
Humboldt Bay Confirmatory Survey Report D-2 5272-SR-03-0