ML25064A344
| ML25064A344 | |
| Person / Time | |
|---|---|
| Site: | 07000754 |
| Issue date: | 03/05/2025 |
| From: | Ollis P GE Hitachi Nuclear Energy |
| To: | Office of Nuclear Material Safety and Safeguards, Document Control Desk |
| References | |
| M250091 | |
| Download: ML25064A344 (1) | |
Text
M250091
March 5, 2025 Chief, Fuel Facility Licensing Branch Division of Fuel Management Office of Nuclear Material Safety and Safeguards US Nuclear Regulatory Commission Washington, DC 20555-0001 Attn: Document Control Desk
Subject:
Vallecitos Nuclear Center (VNC) Effluent Monitoring and Environmental Surveillance Programs 2024 Annual Report
References:
- 1) NRC License SNM 960, Docket 070-00754 Enclosed is the 2024 Effluent Monitoring and Environmental Surveillance Programs Annual Report for the Vallecitos Nuclear Center (VNC) in Sunol, California.
If you have questions regarding this report or need additional information, please contact me using the contact information above.
Sincerely, Phillip D. Ollis Manager, Facility Licensing
Enclosure:
Effluent Monitoring and Environmental Surveillance Programs, 2024 Annual Report Cc:
PDO 25-007 GE Hitachi Nuclear Energy Phillip D. Ollis Manager, Facility Licensing 3901 Castle Hayne Road P.O. Box 780 Wilmington, NC 28402 USA T (910) 616-4018 Phillip.ollis@ge.com
USNRC M250091 March 5, 2025 Page 2 of 2
cc: 1) Leonard Ash, (ACWD), leonard.ash@acwd.com
- 2) Matthew Soby (ACDEH), Matthew.Soby@acgov.org
- 3) Radioactive Materials Licensing Section California Department of Public Health Radiologic Health Branch 1500 Capitol Avenue, Suite 520, MS 7610 Sacramento, CA 95814-5006 Attn: Ira Schneider
- 4) Colleen Winey (Zone 7 Water Agency), cwiney@zone7water.com
- 5) American Nuclear Insurers 95 Glastonbury Boulevard, Suite 300 Glastonbury, CT 06033 Attn: Seth Breitmaier
- 6) USNRC, Region IV 1600 East Lamar Boulevard Arlington, TX 76011-4511 Attn: Regional Administrator
- 7) Osiris Siurano-Perez Project Manager Fuel Facility Licensing Branch Division of Fuel Management US Nuclear Regulatory Commission Mail Stop: TWFN 4A60 Washington, DC 20555-0001
- 8) Duane A. Hardesty Project Manager Office of Nuclear Reactor Regulation Division of Advanced Reactors and Non-Power Production and Utilization Facilities (DANU)
US Nuclear Regulatory Commission OWFN Washington, DC 20555-0001
GEHitachiNuclearEnergy,LLC
EFFLUENT MONITORING AND ENVIRONMENTAL SURVEILLANCE PROGRAMS 2024 ANNUAL REPORT February 28, 2025
M250091 USNRC 02/28/2025
1 NOTICE AND DISCLAIMER GE Hitachi Nuclear Energy, LLC (GEH) prepared this document. GEH and contributors to this document do not:
make any warranty or representation, expressed or implied, that the use of any information disclosed may not infringe privately owned rights; or assume responsibility for liability or damage of any kind, which may result from the use of any information disclosed.
M250091 USNRC 02/28/2025
2 TABLE OF CONTENTS TABLE OF CONTENTS................................................................................................................................ 2 LIST OF FIGURES AND TABLES................................................................................................................ 3 ABSTRACT................................................................................................................................................... 4
1.0 INTRODUCTION
..................................................................................................................................... 5 1.1 Effluent Monitoring Program 5
1.2 Environmental Surveillance Program 6
2.0 EFFLUENT MONITORING DATA.......................................................................................................... 9 3.0 ENVIRONMENTAL SURVEILLANCE DATA........................................................................................ 10 3.1 Groundwater 10 3.2 Stream Bottom Sediment 10 3.3 Vegetation 10 3.4 Gamma Monitoring 10 3.5 Ambient Air Monitoring 10
4.0 REFERENCES
...................................................................................................................................... 11 5.0 DEVIATIONS AND ANOMALIES.......................................................................................................... 12 5.1 Local Action Level Exceedances 12 5.2 Stack Flow Failure 12 6.0
SUMMARY
............................................................................................................................................ 13
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3 LIST OF FIGURES AND TABLES Figure Title Page 1
Topographic Map Of VNC 13 2
Sanitary and Industrial Discharge Treatment Facility 14 3
Water Sampling Locations 15 4
Air Sampling Locations and Gamma Monitoring Points 16 Table Title Page 1
Sample Collection Schedule 17 2
Groundwater Well Information 18 3
Stack Specifications 19 4
Monthly Water Effluent Samples 20 5
Groundwater Samples 21 6
Stream Bottom Sediment Sample 22 7
Vegetation Samples 22 8
Gamma Monitoring Dosimetry Results 23 9
Ambient Air Monitoring 24 10 Stack Air Monitoring - Particulates 25 11 Stack Air Monitoring - Halogens 25
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4 ABSTRACT This report summarizes activities performed and data collected for the Effluent Monitoring and Environmental Surveillance Programs at Vallecitos Nuclear Center (VNC) during the 2024 calendar year.
The program analyzes water, air, sediment, and vegetation samples and measures radiological dose around the site perimeter for compliance with regulatory limits.
Based on the analytical results of radiological samples collected from locations on-and off-site during the reporting period, VNC is compliant with all licenses issued by the U.S. Nuclear Regulatory Commission and California Department of Health, Radiologic Health Branch.
Copies of laboratory analysis reports are on file at VNC.
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1.0 INTRODUCTION
This report summarizes activities performed and data collected for the Effluent Monitoring and Environmental Surveillance Programs at Vallecitos Nuclear Center (VNC) during the 2024 calendar year.
This report has been prepared to demonstrate compliance with state and federal regulations and license requirements. Section 1.0 presents background information, and sections 2.0 and 3.0 present data collected during the monitoring period.
VNC is several hundred acres in size. It is located on the northern side of Vallecitos Valley as shown in Figure 1. Most of the site is undeveloped with hills ranging in elevation from approximately 1,000 to 1,300 feet above sea level. Approximately 135 acres in the southwest corner and situated between the 400-and 600-foot topographic contours are developed. The ground surface of this portion of the site slopes to the southwest.
VNC utilizes three drainage systems: industrial, sanitary, and storm. The industrial and sanitary systems discharge effluent water into one of four 50,000-gallon retention basins located in the southwest corner of the site (Figure 2). The storm drainage system, consisting of natural ditches, discharges storm water into a ditch parallel with Vallecitos Road (State Route 84). Storm drains from Buildings 103, 104, and 106 discharge to the west drainage ditch, and storm drains in the Building 102, 105, 200, and 300 areas discharge to the east drainage ditch. As shown in Figures 2 and 3, these ditches merge prior to exiting the southwest corner of the site.
Groundwater levels of the developed site vary from 2 to 3 feet below ground surface (during winter near Retention Basins 2 and 3) to 30 to 40 feet (during the summer northwest of the road leading to the water tank). A U.S. Geological Survey (USGS) study shows that groundwater generally flows toward the southwest. The velocity of groundwater is estimated by USGS to be about 0.01 ft/day in clays to 8 ft/day in gravels. In areas where gravels with a considerable mixture of clay (most of developed site) are saturated close to the land surface, southwesterly movement occurs at an average rate of approximately 2 ft/day1.
1.1 Effluent Monitoring Program The Effluent Monitoring Program verifies that effluent release limits listed in Appendix B of 10CFR20 are not exceeded. The Program includes measuring radioactive constituents in water discharged through the site sanitary and industrial wastewater systems and air discharged through building exhaust stacks.
Water Discharges Effluent water discharge from VNC is made up of industrial wastewater, sanitary wastewater, and stormwater runoff. Samples of effluent water are taken and analyzed for radiological constituents prior to release. The schedule of sample collection at VNC is presented in Table 1.
Discharges of industrial wastewater consist primarily of non-contact cooling water. The discharges are held in one of two 50,000-gallon retention basins and used for non-potable purposes, such as on-site irrigation. There have been no discharges to surface waters from these retention basins since July 1, 2003. Samples are collected from each basin prior to discharge by irrigation to an on-site field (see Figure 2). In addition, samples from all basin discharges are accumulated and analyzed at specified intervals for a variety of constituents.
Sanitary waste (sludge) is collected in an Imhoff tank before undergoing sand filtration and chlorination by addition of sodium hypochlorite solution. The Imhoff tank is cleaned out periodically, at which time sludge samples are collected and analyzed for radioactive constituents. The Imhoff tank was not cleaned out during 2024. After processing, sanitary wastewater is discharged by irrigation to an on-site field (see Figure 2).
1Adelayofover2yearsfromthenearestpostulatedspillpointtothesiteboundary.
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All on-site irrigation is monitored so that no surface runoff occurs. Storm water runoff contains known contaminants. These waters flow directly to drainage ditches that enter Vallecitos Creek.
Air Effluent Monitoring Several operations at VNC use exhaust stacks, listed in Table 3. For these operations, air is collected from single or multiple operating areas via a ventilation system. The ventilation system is generally comprised of ductwork, particulate filtration systems, blowers, and an exhaust stack. Air effluents from these exhaust stacks are monitored for radiological constituents. Stack air sampling systems are used to determine particulate and halogen releases. Noble gas releases, which are primarily Argon-412, are obtained from charts or electronic integrators on monitoring equipment.
The various site operating licenses (NRC SNM-960, NRC R-33, and California 0017-01) and federal regulations require that air effluents released to unrestricted areas be limited and controlled to maintain the concentrations of radioactive material in the unrestricted area as low as reasonably achievable but at least no greater than the values in Appendix B, Table II of 10CFR20. Compliance with these limits is achieved by establishing average release limits and local action levels for each stack and measuring the average releases through monitoring or sampling of the effluents. The local action levels are generally established as 10% of the license release limits and are based on a measurement above background variation at the 95% confidence level.
Additionally, the EPA COMPLY computer code is used to determine the dose at the site boundary from annual airborne effluents. This evaluation was formerly required when 40CFR61 Subpart I applied to NRC licensees, which included VNC. The regulation was since amended to exclude NRC licensees, but VNC continues to run the COMPLY code to demonstrate compliance with the constraint rule per Regulatory Guide 4.20 and 10CFR20.1101(d) to verify compliance with annual public dose per 10CFR20.1301.
1.2 Environmental Surveillance Program The Environmental Surveillance Program determines if any radioactivity from VNC is detectable in the environment. The Program includes measuring radioactive constituents in groundwater wells, neighboring streams, and vegetation at locations near or beyond the site perimeter. Samples of groundwater, stream bottom sediments, and vegetation are collected at periodicities shown in Table 1.
Groundwater Monitoring Groundwater is monitored by collecting samples from eight wells located on or near VNC and analyzing the samples for radiological constituents. All groundwater wells are sampled annually except for GA, GN, and GP, which are sampled quarterly. A background well, MW-10R, was added in 2022 which is also sampled on an annual basis. Well identification numbers, corresponding California State Well Numbers, and descriptions of locations are listed in Table 2. Well locations are shown in Figure 3.
Vegetation Monitoring Vegetation is monitored by collecting and analyzing samples of vegetation at two locations designated V-2 and Val-IV. V-2 is located on the easternmost stream crossing the south boundary of VNC. VAL-IV is located west of the VNC boundary, about 500 feet down Little Valley Road.
2Inrecenthistory,Argon41dischargeshavebeenexclusivelytheproductofairactivationduringoperationoftheNuclearTestReactor(NTR)
(stacknumber16).TheNTRpermanentlyceasedoperationsonDecember21,2023.AsperGEHLicenseAmendmentRequest-Permanent CessationoftheGENuclearTestReactor(NTR)andPossessionOnlyLicense,datedOctober6,2023,(ADAMSML23279A110)continuedeffluent monitoringasaninputtothesiteannualeffluentreporthasbeendiscontinued.
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Stream Bottom Sediment Monitoring Stream bottom sediment is monitored by collecting and analyzing samples at one location designated as S-4. S-4 is located at the outfall of the retention basins at south boundary of site.
Air Monitoring There are four environmental air monitoring stations at VNC designated as A-1 through A-4. The stations are positioned approximately 90 apart around the operating facilities of the site. The locations of the stations are shown in Figure 4.
Each air monitoring station is equipped with a membrane filter and an activated charcoal cartridge. The filter is changed weekly3 and counted for gross alpha and gross beta radiation. The cartridge is removed and analyzed only in the event of a suspected radioactive iodine release.
Gamma Monitoring There are 20 locations at VNC for measuring gamma radiation in the environment, shown in Figure 4.
Each station is constructed of a mailbox containing an optically stimulated luminescence (OSL) dosimeter that meets the requirements of ANSI/HPS Standard N13.37. The dosimeters are exchanged annually.
For reporting purposes, the dosimeters are distributed as follows:
South Boundary: Stations 1 through 3 East Boundary: Stations 4 through 6 North Boundary: Stations 7, 12, and 13 West Boundary: Stations 8 through 11 Background Dosimeters: Stations 14 through 20 The dosimeter vendor (Landauer) reports the dose measurements of each dosimeter and determines the background dose measurement. Background dose is determined using dosimeters exposed to background radiation at VNC.
1.3 Laboratory Analyses On-site and external laboratories perform the analyses of samples collected at VNC. Sample radioanalytical results are reported as a measured value or as less than minimum detectable activity (MDA) values. Values within the statistical background may be listed as zero or as positive or negative numbers. All analyses are performed using approved EPA methodology with minimum sensitivities equal to or less than local action levels. Original radioanalytical results are maintained at VNC.
On-site Laboratory Analyses The on-site laboratory at VNC can quantitatively analyze gross alpha-and beta-emitter radioactivity in air and water. The laboratory is also capable of quantitative tritium analysis in water and qualitative isotopic identification with gamma spectroscopy.
Off-site Laboratory Analyses External laboratories contracted to analyze VNC samples are Davi Laboratories, located in Hercules, California, and GEL Laboratories, located in Charleston, South Carolina. Both Davi and GEL Laboratories are accredited by the California Environmental Laboratory Accreditation Program (certificates 1438 and 2940, respectively).
3Duringdustyconditions,filtermaybechangedmorefrequentlyasdeterminedbyRadiologicalMonitoringTechnicians.
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Davi laboratories is used for routine radiological analyses on samples of water, stream bottom samples, and vegetation. GEL Laboratories is used as needed for advanced radionuclide analysis, such as for alpha spectroscopy and quantification of hard-to-detect radionuclides.
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2.0 EFFLUENT MONITORING DATA Radioanalytical results of air and water effluent samples collected in 2024 from locations on-and off-site indicate VNC is compliant with all licenses issued by the U.S. Nuclear Regulatory Commission and California Department of Health, Radiologic Health Branch.
2.1 Water Effluent Table 4A summarizes radioanalytical results of composite industrial and sanitary effluent water samples prior to release by on-site irrigation. VNC has no radiological liquid effluent pathways, and sampling for radiological contamination in industrial effluent is not required by the State of California. Monthly sampling results are from composite samples of one or more water releases.
No clean-out or sampling of the Imhoff tank was performed in 2024..
All treated sanitary and industrial wastewater was discharged via the VNC on-site irrigation system.
2.2 Air Effluent Air effluents are monitored for stack shown in Table 3. Analytical results of stack air samples are listed in Tables 10 through 12.
Using the parameters of Table 3 and Tables 10 through 12, the calculated Effective Dose Equivalent at Screening Level 2 resulting from the annual measured releases, as calculated by the EPAs COMPLY Code, are:
Property Line:
1.0E-02 mrem/year due to all emissions 1.3E-04 mrem/year from Iodine Site Developed Area:
5.7E-02 mrem/year due to all emissions 1.4E-03 mrem/year from Iodine.
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3.0 ENVIRONMENTAL SURVEILLANCE DATA The Environmental Surveillance Program determines if any radioactivity from VNC is detectable in the environment. The Program includes measuring radioactive constituents in groundwater wells, neighboring streams, and vegetation at locations near or beyond the site perimeter.
All radioanalytical results from environmental samples collected in 2024 indicate VNC is compliant with all licenses issued by the U.S. Nuclear Regulatory Commission and California Department of Health, Radiologic Health Branch.
3.1 Groundwater Analytical results of groundwater samples from the monitoring wells listed in Table 2 are listed in Table 5.
3.2 Stream Bottom Sediment Analytical results of the stream bottom sediment sample are listed in Table 6.
3.3 Vegetation Analytical results of vegetation samples are listed in Table 7.
3.4 Gamma Monitoring Dose results from gamma monitoring are listed in Table 8.
3.5 Ambient Air Monitoring Analytical results of environmental air samples collected are in Table 9.
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4.0 REFERENCES
Licenses containing requirements for this Environmental Monitoring Report are as follows:
- 2. United States Nuclear Regulatory Commission (USNRC) License R-33
- 3. State of California Radiologic Health Branch License 0017-01
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5.0 DEVIATIONS AND ANOMALIES This section presents anomalies, deficiencies, or deviations in adherence to the Effluent Monitoring and Environmental Surveillance Programs at VNC for the 2024 calendar year.
5.1 Local Action Level Exceedances There were four weeks in 2024 where environmental air samples exceeded gross beta radioactivity local action levels established by VNC. All samples were recounted and analyzed further with gamma spectroscopy in accordance with VNC procedures.
The exceedances occurred in October and December 2024, which is consistent with past seasonal variations in environmental radioactivity at VNC. No radionuclides related to VNC operations were observed on the air sample filters. The increase in beta radioactivity was attributed to normal, seasonal meteorological changes that increase ambient radioactivity levels in the VNC region.
5.2 Stack Flow Failure The air sample pump (Hoffman blower) in building 103 failed on 27 January 2024, and was restored to service on 12 February 2024. The building 103 stack particulate sampler and charcoal filter were inoperable during this time. No operations were conducted in building 103 during this period that had the potential to generate airborne radioactivity.
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6.0
SUMMARY
Based on the 2024 analytical results of water, air, sediment, and vegetation samples and measured radiological doses around the VNC perimeter, VNC is compliant with all regulatory requirements and licenses issued by the U.S. Nuclear Regulatory Commission and California Department of Health, Radiologic Health Branch. The effluent monitoring and environmental surveillance programs in place at VNC continue to be effective.
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Figure 1. Topographic Map of GE Vallecitos Nuclear Center based on USGS Maps, Lacosta Valley and Livermore, CA
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Figure 2. Sanitary and Industrial Discharge Treatment Facility
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Figure 3. Water Sampling Locations
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Figure 4. Air Sampling Locations and Gamma Monitoring Points VALLECITOS ROAD (HWY 84)
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18 TABLE 1 SAMPLE COLLECTION SCHEDULE Location Constituent Sample Type Frequency E-001 and E-002 (Basin 1 - 4)
Gross Alpha Gross Beta Gross Alpha Gross Beta Grab Grab Composite Composite Each discharge Each discharge Monthly Monthly S-4 Stream Bottom (Sediments)
Gross Alpha Gross Beta Co-60, Cs-137 Grab Grab Grab Annually, usually first week in May Annually, usually first week in May Annually, usually first week in May V-2 & VAL IV (Vegetation)
Gross Alpha Gross Beta Grab Grab Annually, usually first week in April Annually, usually first week in April Groundwater Wells Gross Alpha Gross Beta Tritium Sr-90 Grab Grab Grab Grab Quarterly (GA, GP, GN) or Annually Quarterly (GA, GP, GN) or Annually Quarterly (GA, GP, GN) or Annually Quarterly (GA, GP, GN) or Annually
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19 TABLE 2 GROUNDWATER WELL INFORMATION Site Well Number California State Well Number Location Description GN 4S/1E-2N1 Southeast of Building 105 GA 4S/1E-10A1 Southwest of Building 102 GP 4S/1E-10P3 0.6 miles southwest of site entrance (private property)
MW-1 4S/1E3R2 Bldg. 102 Parking Lot MW-7 4S/1E-10G3 Southwest from Basins MW-8 4S/1E2M01 Southwest of GETR Reactor MW-9S 4S/1E2P1 Southwest of EVESR and VBWR Reactors MW-9D 4S/1E2P2 Southwest of EVESR and VBWR Reactors EVESR-SE N/A 20 ft east of EVESR at southwest exterior corner MW-10R (Background) 4S-1E02L004 East-northeast of the GETR, EVESR, and VBWR Reactors
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20 TABLE 3 STACK SPECIFICATIONS Stack Number Location Components Serviced Height (ft above ground)
Diameter (in)
Flow Rate (cfm) 4 Bldg.
102A Remote Handling Operation Isotope Production Facility Radiochemistry Remote Handling Operations Radioactive Materials Storage Room 75 66 35,634.7 12 Bldg. 103 Metallurgy and Ceramics Laboratories Chemistry Laboratories 48 60 28,851.2 16 Bldg. 105 Nuclear Test Reactor 45 13.5 x 13.5 1,477.7 261 Area 200 General Electric Test Reactor (GETR) 29 19 N/A 30 Waste Evaporato r
Liquid Waste Evaporator 25 13 x 17.75 3,144.7 341 Waste Storage Waste Storage Facility (Sandblast Room) 25 13 x 17.75 N/A 371 HSF Bunker Bunker Area of Hillside Storage Facility 40 35 N/A 1Stacks 26, 34, and 37 did not operate during 2024
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21 TABLE 4 MONTHLY WATER EFFLUENT SAMPLES Action Levels Gross Alpha: 7.1 pCi/L Gross Beta: 7.1 pCi/L Tritium: 2000 pCi/L Monthly Effluent (Industrial)
Monthly Effluent (Sanitary)
(pCi/L)
(pCi/L)
Month Gross Alpha Gross Beta Tritium Gross Alpha Gross Beta Tritium January 3.49 1.45 515 1.26 3.10 313 February 3.78 3.48 816 1.18 3.83 297 March 4.27 2.97 299 2.13 2.30 19 April 2.04 4.76 400 2.17 2.42 0
May 4.98 4.79 75 0.83 2.33 244 June No Discharge No Discharge July No Discharge No Discharge August 3.15 3.74 319 No Discharge September 4.48 3.05 899 4.55 3.12 148 October 1.89 1.99 638 No Discharge November 2.43 2.52 43 No Discharge December 3.64 1.18 418 0.98 1.49 380
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22 TABLE 5 GROUNDWATER SAMPLES Action Levels Gross Alpha: 7.1 pCi/L Gross Beta: 7.1 pCi/L Tritium: 2000 pCi/L 4S/1E-2N1 (GN) 4S/1E-10A1 (GA) 4S/1E-10P3 (GP)
(pCi/L)
(pCi/L)
(pCi/L)
Month Gross Alpha Gross Beta Sr-90 Tritium Gros s
Alpha Gross Beta Sr-90 Tritiu m
Gross Alpha Gross Beta Sr-90 Tritiu m
February 3.28 0.45 0.16 293 1.77 1.21 0.00 0
4.25 4.66 0.14 329 April 2.01 2.73 1.33 90 1.18 4.35 1.31 131 4.32 2.53 0.49 325 September 2.55 2.50 0.23 450 1.82 2.65 0.82 274 3.81 2.69 2.19 0
December 4.11 3.86 1.99 681 3.50 0.86 0.00 553 3.54 4.82 1.57 596 Annual Average 2.99 2.39 0.93 379 2.07 2.27 0.53 240 3.98 3.68 1.10 313 MW-8 (4S-1E2M01)
MW-9S (4S-1E2P1)
(pCi/L)
(pCi/L)
Month Gross Alpha Gross Beta Sr-90 Tritium Gross Alpha Gross Beta Sr-90 Tritium February 2.75 2.67 0.00 842 1.80 2.21 0.33 73 MW-9D (4S-1E2P2)
EVESR-SE (pCi/L)
(pCi/L)
Month Gross Alpha Gross Beta Sr-90 Tritium Gross Alpha Gross Beta Sr-90 Tritium February 2.69 1.36 0.71 220 4.09 3.61 0.00 384 MW-1 (1E-3R2)
MW-7 (1E-10G3)
(pCi/L)
(pCi/L)
Month Gross Alpha Gross Beta Sr-90 Tritium Gross Alpha Gross Beta Sr-90 Tritium February 4.32 2.31 0.76 951 2.98 2.40 0.00 915 MW-10R (1E02L004) - Background Well (pCi/L)
Month Gross Alpha Gross Beta Sr-90 Tritium February 3.15 2.97 0.43 110
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23 TABLE 6 STREAM BOTTOM SEDIMENT SAMPLE Action Levels Gross Alpha: 11 pCi/g Gross Beta: 15 pCi/g Sample Month Gross Alpha (pCi/g)
Gross Beta (pCi/g)
Co-60 (pCi/g)
Cs-137 (pCi/g)
S-4 June 1.83 1.76 0.00073 0.00065 TABLE 7 VEGETATION SAMPLES Action Levels Gross Alpha: 2.4 pCi/g Gross Beta: 9.3 pCi/L Sample Month Gross Alpha (pCi/g)
Gross Beta (pCi/g)
V-2 March 0.37 4.49 VAL-IV March 0.27 1.11 Average 0.32 2.80
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24 TABLE 8 GAMMA MONITORING DOSIMETRY RESULTS Dosimeter collection date: December 2024 South Boundary East Boundary West Boundary North Boundary
Background
Station (mRem/yr) 1 Station (mRem/yr) 1 Station (mRem/yr)1 Statio n
(mRem/yr)1 Station (mRem/yr) 1 1
75.0 4
70.6 7
80.8 8
70.1 14 70.9 2
77.3 5
70.5 12 73.2 9
61.7 15 70.7 3
71.1 6
73.5 13 79.6 10 70.9 16 70.9 11 76.8 17 73.6 18 78.8 19 75.0 20 73.2 1Gross values shown (no background subtraction)
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25 TABLE 9 AMBIENT AIR MONITORING Action Levels Beta: 6.6x10-14 µCi/ml Alpha: 5.9x10-14 µCi/ml Average Activity (µCi/ml)
STATION ONE STATION TWO STATION THREE STATION FOUR Beta Alpha Beta Alpha Beta Alpha Beta Alpha January 2.19E-14 8.17E-16 2.09E-14 1.32E-15 2.37E-14 1.62E-15 1.79e-14 1.25e-15 February 2.57E-14 1.33E-15 2.43E-14 1.26E-15 3.36E-14 1.19E-15 1.93e-14 1.18e-15 March 2.24E-14 1.33E-15 2.46E-14 1.35E-15 2.73E-14 1.18E-15 1.83e-14 8.43e-16 April 2.35E-14 1.34E-15 2.62E-14 1.38E-15 3.41E-14 1.86E-15 2.13e-14 1.21e-15 May 1.98E-14 1.15E-15 2.39E-14 1.39E-15 2.64E-14 1.54E-15 1.67e-14 1.13e-15 June 2.22E-14 1.14E-15 2.43E-14 1.60E-15 3.17E-14 1.86E-15 2.26e-14 9.99e-16 July 2.63E-14 1.30E-15 3.10E-14 1.93E-15 3.48E-14 1.93E-15 2.56e-14 1.58e-15 August 2.47E-14 1.18E-15 2.72E-14 1.10E-15 3.43E-14 1.67E-15 2.40e-14 1.42e-15 September 3.18E-14 1.79E-15 3.39E-14 1.32E-15 4.39E-14 1.76E-15 3.25e-14 1.70e-15 October 4.21E-14 1.85E-15 4.17E-14 1.94E-15 5.41E-14 2.14E-15 3.96e-14 1.60e-15 November 3.05E-14 1.76E-15 3.00E-14 1.56E-15 3.39e-14 1.73e-15 2.81e-14 1.68e-15 December 8.27E-14 2.03E-15 7.93E-14 2.60E-15 1.01e-13 3.62e-15 6.64e-14 1.93e-15 Annual 3.01E-14 1.42E-15 3.14E-14 1.56E-15 3.92E-14 1.80E-15 2.69E-14 1.37E-15 1Sample activities exceeding action levels are further analyzed for VNC radionuclides per VNC procedure VSS 7.2, Radioactive Effluent Control.
M250091 USNRC 02/28/2025
26 TABLE 10 STACK AIR MONITORING - PARTICULATES Total Activity (µCi)
STACK 4 STACK 12 STACK 16 STACK 30 Beta Alpha Beta Alpha Beta Alpha Beta Alpha January 6.32E-01 1.82E-02 1.45E-01 7.76E-03 2.77E-02 1.02E-03 3.03E-02 1.35E-03 February 5.09E-01 1.64E-02 7.91E-02 3.27E-03 2.15E-02 7.10E-04 2.79E-02 1.42E-03 March 6.91E-01 1.11E-02 1.58E-01 9.82E-03 2.24E-02 1.02E-03 2.64E-02 1.26E-03 April 9.42E-01 1.96E-02 1.75E-01 9.82E-03 2.31E-02 1.26E-03 3.92E-02 1.57E-03 May 9.38E-01 1.32E-02 1.55E-01 1.18E-02 1.43E-02 8.58E-04 2.88E-02 1.54E-03 June 1.07E+00 1.28E-02 1.59E-01 8.86E-03 1.19E-02 6.06E-04 3.06E-02 1.26E-03 July 1.59E+00 2.17E-02 1.68E-01 6.54E-03 2.45E-02 1.01E-03 4.35E-02 1.42E-03 August 9.71E-01 1.10E-02 1.39E-01 5.97E-03 2.15E-02 6.21E-04 3.00E-02 1.29E-03 September 1.33E+00 1.85E-02 1.91E-01 1.08E-02 3.07E-02 1.08E-03 3.86E-02 1.38E-03 October 1.12E+00 1.46E-02 1.43E-01 2.31E-03 4.35E-02 1.67E-03 2.96E-02 1.38E-03 November 6.91E-01 1.67E-02 1.50E-01 5.00E-03 2.42E-02 9.17E-04 2.88E-02 1.29E-03 December 1.19E+00 3.25E-02 1.59E-01 7.31E-03 4.49E-02 1.76E-03 3.13E-02 7.87E-04 Annual 1.17E+01 2.06E-01 1.82E+00 8.93E-02 3.10E-01 1.25E-02 3.85E-01 1.60E-02 TABLE 11 STACK AIR MONITORING - HALOGENS I-131 Activity (µCi)
STACK 4 STACK 12 STACK 16 Annual Release
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