HBL-21-017, Clarification Regarding Final Status Survey Report for Humboldt Bay Power Plant
ML21301A143 | |
Person / Time | |
---|---|
Site: | Humboldt Bay |
Issue date: | 10/28/2021 |
From: | Zawalick M Pacific Gas & Electric Co |
To: | Document Control Desk, Office of Nuclear Material Safety and Safeguards |
References | |
HBL-21-017 | |
Download: ML21301A143 (10) | |
Text
m PacHic Gas and Electric Company*
Maureen R. Zawalick Vice President Generation Business Diablo Canyon Power Plant Mail code 104/6/608 P.O. Box 56 and Technical Services Avila Beach, CA 93424 805.545.4242 Internal: 691.4242 PG&E Letter HBL-21-017 ATTN: Document Control Desk U.S. Nuclear Regulatory Commission Washington, DC 20555-0001 Humboldt Bay Power Plant, Unit 3 Docket No. 50-133, DPR-7 Clarification Regarding Final Status Survey Report for Humboldt Bay Power Plant
Reference:
- 1. PG&E Letter HBL-21-010, Final Status Survey Reports for the Humboldt Bay Power Plant, dated June 8, 2021 (ML21160A224)
- 2. Email from NRC Project Manager, Amy Snyder, Humboldt Bay Unit 3 Clarification Question, dated October 26, 2021
- 3. PG&E Letter HBL-21-011, Final Status Survey Report for Humboldt Bay Power Plant, dated July 13, 2021 (ML21194A441)
Dear Commissioners and Staff:
Pacific Gas and Electric Company (PG&E) is providing this letter to clarify three different items associated with NRC review of various Humboldt Bay Power Plant (HBPP) Final Status Survey (FSS) Reports.
In Reference 1, PG&E submitted three FSS Reports for HBPP. Per a clarification phone call with the NRC on October 21, 2021, PG&E is clarifying information included in Enclosure 3 of Reference 1. Enclosure 3 of Reference 1 described an instance where investigative sample OOL01-03-027-F-I, collected during a walkover survey, indicated elevated Cesium-137 at 2.68E+01 picocuries per gram. The elevated reading was bounded and a pre-sample one minute static count confirmed its location. An investigation sample was taken and a post sample one minute static count survey was performed. The post sample survey result was consistent with survey area background levels. This process ensured the area was remediated by sampling. An in situ object characterization system shot over the investigative sample location was taken as additional verification that the as-left location was less than the derived investigation levels specified in the FSS Plan.
Per a clarification phone call with the NRC on October 21, 2021, PG&E is following up to provide additional clarifying information regarding the process for radionuclides of concern (ROCs) in the FSS Reports (FSSRs). For any specific survey unit, if any ROCs were neither deselected nor reported (e.g., Nb-94, Eu-152, Eu-154, Np-237, and Am-
Document Control Desk PG&E Letter HBL-21-017 Page 2 241 are typically not reported in most of the FSSRs), then those ROCs were not detected at concentrations above their respective minimum detectable concentration and/or were of such low concentration that it had, on average, negligible potential dose impact. As a result, those ROCs were not reported for that particular survey unit.
In Reference 2, NRC requested that PG&E provide the analytical results associated with the composite sample of the Waste Management Facility Pad described in Reference 3. The Enclosure, Gamma Spectrum Analysis, provides the analytical results of the Waste Management Facility Pad composite sample associated with survey unit OOL10-24-FSR.
PG&E makes no new or revised regulatory commitments (as defined in NEI 99-04) in this letter.
If you have any questions or require additional information, please contact Mr. Philippe Soenen at (805) 459-3701.
Sincerely, Maureen R. Zawalick Vice President Generation, Business and Technical Services Enclosure cc: Humboldt Distribution cc/enc: Scott A. Morris, NRC Region IV Administrator Amy M. Snyder, NRC Reactor Decommissioning Branch Project Manager
PG&E Letter HBL-21-017 Enclosure Gamma Spectrum Analysis FSS-2489, OOL10-24-002-M-C Composite
- ** GAMM A S P E C T R U M A N A L Y S I S *****
Repor t Generated On 10/30/ 2 019 1:01:18 PM Sampl e Identification FSS-2489 Sample Title OOLl0 0 02 - M-C Composite Sample I nformation Sample Type Med ia Sample Geometry Peak Lo c at e Threshold 3.00 Peak Locate Range (in channels) 100 - 4096 Peak Area Range (in channe l s) 100 - 4096 Identification Energy Tolerance 1. 000 keV Sample Size 3 .770E+00 2 g Sample Taken On 10/ 30/20 19 11:05:00 AM Acquisition Started 10/30/2019 11 :49:05 AM Live Time 3600.0 seconds Real Time 3607 . 6 seconds Dead Time 0~21 %
Energy Calibration Used Done On 12/4/2015 Efficiency Calibration Used Done On 6/11/2019 Efficiency ID 500ml BeakerDl.6 Performed by ,6;. d-,,,v--u.. Date 10 - lo - (~
Alderman, Anderson, Burrell, Eckhardt , tephens Reviewed by Date H * -3o- lf i
C AlderJ.lliiD--? Anderson
Peak Locate Analysis Report 10/30/2019 1:01:19 PM Page 2
- P E A K L O C A T E R E P O R T *****
Detector Name: DET0848 Sample
Title:
OOLl0-24-002-M-C Composite Peak Locate Performed on: 10/30/2019 1:01:18 PM Peak Locate From Channel: 100 Peak Locate To Channel: 4096 Peak Search Sensitivity: 3 .0 0 Peak Centroid Centroid Energy Peak No. Channel Uncertainty (keV) Significance 1 127.13 0.4903 63 . 32 3.62 2 150.12 0.3864 74.78 4.08 3 154.80 0.3779 77.10 5.57 4 477.48 0.2658 238.66 7.29 5 484 . 67 0.4191 242.16 3.79 6 590 . 55 0.3364 295 . 25 4.87 7 704.13 0.2417 352 .0 8 8.49 8 955.22 0.1017 47 7.7 2 45 .59 9 1166.35 0.2938 583 .3 3 5.19 10 1218.78 0.2373 609.46 7.91 11 1322.95 0.3097 661.62 4.86 12 1536.84 0.4108 76 8 .60 3.17 13 1 822.59 0.3141 911.42 3.90 14 1938.27 0.3352 969.30 3.36 15 2922.61 0.1823 1461.26 9.56
? = Adjacent peak noted Errors quoted at 2.000 sigma
Peak Analysis Report 10/30/2019 1:01:19 PM Page 3
- P E A K A N A L Y S I S R E P O R T *****
Detector Name: DET0848 Sample
Title:
OOLl0 002-M-C Composite Peak Analysis Performed on: 10/30/2019 1:01:18 PM Peak Analysis From Channel: 100 Peak Analysis To Channel: 4096 Peak ROI ROI Peak Energy FWHM Net Peak Net Area Continuum No. start end centroid (keV) (keV) Area Uncert. Counts F 1 123- 130 127.22 63 . 32 0 . 68 6.89E+001 39.98 3.25E+002 M 2 146- 158 150.12 74.78 0.90 l . 44E+002 37.76 3.42E+002 m 3 146 - 158 154.75 77.10 0.90 l . 56E+002 40.06 3.41E+002 M 4 473- 489 477.48 238.66 1.17 3.35E+002 45.02 2.66E+002 m 5 473- 489 484.48 242.16 1.17 l.11E+002 29 . 56 2.54E+002 F 6 586- 595 590 . 56 295 . 25 1.07 1 . 31E+002 34.92 3 . 18E+002 F 7 699- 709 704 . 14 352 . 08 1. 26 2 . 84E+002 37.42 1.68E+002 F 8 949- 960 955 . 26 477.72 l. 26 6 . 39E+003 154.74 l . 20E+002 F 9 1162- 1170 1166 . 42 583 . 33 l. 36 l . 02E+002 20.2 7 2 . 20E+001 F 10 1 214- 1224 1218 . 66 609 . 46 l. 34 l . 98E+002 28 . 11 4 . 03E+001 F 11 1319- 1328 1322 . 96 661 . 62 1.08 5 . 29E+001 17 . 13 3 . 93E+001 F 12 1534- 1540 1536 . 90 768.60 0 . 99 l . 91E+001 11.49 1.83E +001 F 13 1817- 182 7 1822 . 58 91 1. 42 1 . 44 5.53E+001 16.48 2 . 74E+001 F 14 1934- 1943 1938.36 969 . 30 1 . 47 4 . 13E+00 1 1 4 . 98 2 . 67E+001 F 15 2917- 2929 2922 . 75 1461 . 26 1.89 3.88E+002 38 . 43 l . 81E+001 M First peak in a mu l tiplet region m Other peak in a multiplet region F = Fitted singlet Errors quoted at 2.000 sigma
Interference Corrected Activity Report 10/30/2019 1:01:19 PM Page 4
- N U C L I D E I D E N T I F I C A T I O N R E P O R T *****
Sample
Title:
OOLl0-24-002-M-C Composite Nuclide Library Used: C:\GEN I E2K\CAMFILES\HBPP.NLB IDENTIFIED NUCLIDES Nuclide Id Energy Yield Activity Activity Name Confidence (keV) ( %) (pCi/g Uncertainty Bi - xRay 0 . 554 77.11* 100.00 6.02527E - 002 1.95979E - 002 87.20 36 . 00 Pb-xRay 0.437 72.80 55.00 74.97* 100 . 00 5.81523E-002 1 . 91561E-002 Be-7 0 . 997 477.59* 10 . 42 3.75168E+001 4.75672E+000 K-40 0.968 1460.81* 10 . 67 4 . 83111E+000 6.15037E-001 Cs-137 1 . 000 661.65* 85 . 12 4.75849E - 002 1.64414E - 002 Tl - 208 0 . 691 277 . 35 6 . 80 583 . 14* 84.20 8.53015E-002 l . 97721E-002 860 . 37 12 . 46 Pb-212 0 . 894 238.63* 44 . 60 2 . 81488E - 001 5 . 88232E - 002 300 . 09 3 . 41 Bi - 2 1 4 0.465 609 . 31* 46.30 3.09928E - 001 5 . 75907E-002 1120 . 29 1 5.10 1764 . 49 15 . 80 Pb-214 0 . 997 241 . 98
- 7 . 49 5 . 63247E-00 1 1 . 74448E - 001 295 . 21* 1 9 . 20 2 . 96 7 58E - 001 9.20350 E -002 351 . 92* 37 . 20 3 . 75093E-001 7.47826E-002 Ac - 228 0.559 338 . 32 11.40 91 1 .07* 27 .7 0 l.90279E-001 5 . 93854E-002 969.11* 1 6 . 60 2 . 47489E - 001 9 . 2 1 869E-002
- =En ergy line found in the spectrum .
@=Energy line not used for Weighted Mean Activity Energy Tole r ance : 1 . 000 keV Nuclide conf i dence index threshold 0 . 30 Errors quoted at 2 . 000 sigma
Interference Corrected Activity Report 10/30/2019 1:01:19 PM Page 5 I N T E R F E R E N C E C O R R E C T E D R E P O R T *****
Nuclide Wt mean Wt mean Nuclide Id Activity Activity Name Confidence (pCi/g Uncertainty Bi-xRay 0.554 6.025274E - 002 1.959792E-002 Pb-xRay 0.437 5.815228E-002 l.915606E-002
.,,,- Be- 7 , . ~*"'"l'""'c.. 0.997 3.751678E+001 4.756716E+000 K- 40 0.968 4.831114E+000 6.150366E-00 1
....-ts - 137 1.000 4.758488E-002 1.644141E-002 Tl-208 0.691 8.530150E-002 1. 9 7721 3E-002 Pb-2 12 0.894 2.814882E-001 5 .88 2321E-002 Bi-214 0.465 3.099282E-001 5.759072E-002 Pb - 2 14 0.997 3.657965E-001 5.507068E-002 Ac-228 0.559 2 . 070573E-001 4.992354E-002
? nuc l ide is part of an undetermined solution X nuclide rejected by the interference analysis
@ nuclide contains energy lines not used in Weighted Mean Activity Errors quoted at 2.000 sigma
Interference Corrected Activity Report 10/30/2019 1:01:19 PM Page 6
- UN I D E N T I F I E D PE AK S **********
Peak Locate Performac:Lon~* ~J~D. t.J_o_,l2-0l9 J
- QL;,_J._.,_R_,_,P
'-'M Peak Locate From Channel : 100 Peak Locate To Channel : 4096 Peak Energy Peak Size in Peak CPS Peak Tol.
No . (keV) Counts per Second % Uncertainty Type Nuclide F 1 63 . 32 1.9136E-002 58.03 Tol.
II rt Th-234 /!.):::- >
F 12 768.60 5.3160E - 003 60.04 (:;;* .:u ~ /0 __ J u -*1'\
M = First peak in a multiplet region m = Other peak in a multiplet region F Fitted singlet Errors quoted at 2 . 000 sigma
Nuclide MDA Report 10/30/2019 1: 01:19 PM Page 7 N U C L I D E MD A R E P O R T *****
Detector Name: DET0848 Sample Geometry :
Sample Tit l e : OOLl0-24-002-M-C Composite Nuclide Library Used: C:\GENIE2K\CAMFILES\HBPP.NLB Nuclide Energy Yield Line MDA Nuclide MDA Activity Dec. Level Name (keV) ( %) (pCi/g ) ( pCi/g ) (pCi/g ) (pCi/g
+ K-4 0 1460 . 81"k 10.67 3 .18E -001 3.18E-001 4.83E+000 l. 42E-001 Co-60 1173.22 100.00 4.12E-002 3.66E-002 1.43E-002 1.91E-002 1332.49 100.00 3.66E - 002 1.96E-002 l . 66E-002 Nb-94 702 . 63 100.00 2.87E - 002 2.87E-002 -1 . 22E - 002 l .33E-00 2 871.10 100.00 3.35E-002 2.20E-002 l.55E-002 Ag-108m 433.93 89.90 3.75E-002 3.75E-002 -2.71E-002 1.79E-002 614.37 90 . 40 5 . 06E-002 -3.22E-003 2.42E-002 722 . 95 90 . 50 3 .99E-002 -3.13E-002 1.87E-002 Cs-134 569.31 15.43 l . 91E-001 3 .56E-002 4 . 27E-002 8 . 96E-002 604 . 70 97 . 60 4.45E - 002 -9 . 19E-003 2 . 12E-002 795 . 84 85 . 40 3 . 56E-002 1 . l0E-002 l.64E-002
+ Cs - 137 661 . 65* 85.12 3 . 33E-002 3.33E - 002 4.76E - 002 1.54E-002 Eu-152 121.78 28.40 l . 09E-001 l.09E-001 8 .0 lE-003 5.33E -002 244.69 7 . 49 5 . 27E-001 l . 53E-003 2 . 57E-001 344 . 27 26.50 1.45E-001 3 . 48E-002 7 . 0lE-002 778 . 89 12.7 4 2 . 56E-001 1.58E -0 01 1.19E-001 964 . 01 14 . 40 3 . 09E - 001 -4.27E -002 1 . 45E - 001 1085 . 78 10.00 3 . 57 E-001 -3.49E - 002 1.64E-001 11 12.02 13 . 30 2.61E-001 -2.94E-001 1.20E-001 1407.95 20 .7 0 l . 76E-001 7.34E - 002 7.96E - 002 Eu-154 123 . 07 40 .5 0 7.62E - 002 7.62E-002 1.71E - 002 3.71E-002 723 . 30 19.70 1 . 92E-001 2 . 64E-002 9.02E-002 873.19 11 . 50 2 . 79E-001 6.14E-002 1 . 28E-001 996.32 10.30 3 . 16E-00 1 -6 .23E-002 1.45E -00 1 1004 . 76 17.90 2 . l0E-001 1.17E - 001 9 . 74E - 002 1274 . 45 35 . 50 9.85E - 002 - 1. 03E - 00 1 4 . 46E - 002 Eu-155 105.31 20.70 1.29E-001 1.29E - 001 -2 . 88E-004 6.26E-002
+ Ac - 228 338.32 11.40 3 . 57E-001 l.09E-001 2.80E - 001 1.73E-001 911 .0 7* 27.70 1.09E-001 1.90E-001 4.99E-002 969 .11
- 16 .60 l . 83E-001 2 . 47E-001 8 . 34E-002 Th-234 63.29 3 . 80 1 . 52E+000 6 . 54E-001 l.SlE+000 7 . 40E-001 92 . 59 5.41 6 . 54E-001 6 . 94E - 00 1 3.19E-001 U- 235 143 . 76 10.50 2.79E-001 7.19E-002 -1 . 52E - 001 l . 36E-001 185.72 54.00 7 . 19E-002 6.49E-002 3.51E-002 Np-237 311.98 38.60 1 . 09E-001 1.09E - 001 l.31E - 001 5 . 28E-002 U-238 1001.03 0.84 4 . 35E+000 4 . 35E+000 l . 53E+000 2 . 0lE+000 Am-241 59.54 35.90 l .7 1E-001 1.71E-001 - 1. 64E-001 8.33E-002
+ Nuclide identified during the nuclide identification
- = Energy line found in the spectrum
>=Calcu l ated MDA i s zero due to zero counts in the region , or the region is outside the spectrum, or MDA 'has not been calculated
@ Half-life too short to be able to perform the decay correction