ML25345A136
| ML25345A136 | |
| Person / Time | |
|---|---|
| Site: | Oyster Creek |
| Issue date: | 12/11/2025 |
| From: | Holtec Decommissioning International, Radiation Safety & Control Services |
| To: | Office of Nuclear Material Safety and Safeguards, Office of Nuclear Reactor Regulation |
| Shared Package | |
| ML25345A092 | List:
|
| References | |
| HDI 25-039 24-103, Rev 0 | |
| Download: ML25345A136 (0) | |
Text
Distribution Coefficient (Kd) of Radionuclides in Soil Samples from the Oyster Creek Generating Station Technical Support Document No.24-103 Revision 0 Prepared by:
Melville Dickenson, PhD, Geochemist Reviewed by:
David Averil, Hydrogeologist Approved by: ______________________________________________________
Matt Darois, CGWP, Director of Environmental & Engineering Radiation Safety & Control Services, Inc 93 Ledge Road, Seabrook, NH 03874 1-800-525-8339 (603) 778-2871 (Outside USA) www.radsafety.com March 27, 2025 RSCS Radiation Safety & Control Services 91 Portsmouth Avenue, Stratha m, NH 03885-2468 prione 1-800-525-8339 - ax. 603-778-6879 info@radsafety.com - www.radsafety.com
RSCS TSD 24-103 Page 1 of 31 Distribution Coefficient (Kd) of Radionuclides in Soil Samples from the Oyster Creek Generating Station Contents 1
Introduction......................................................................................................................... 3 2
Partition Coefficient............................................................................................................ 3 3
Data Quality Objectives....................................................................................................... 4 Sample Locations.................................................................................................................... 4 3.1 Field Sampling Process................................................................................................ 9 3.2 Analysis Parameters.................................................................................................. 12 3.3 Laboratory Experiment and Sample Analysis............................................................ 12 3.3.1 Liquid Scintillation................................................................................................. 14 3.3.2 Gamma Spectroscopy........................................................................................... 14 3.4 Quality Assurance..................................................................................................... 15 4
Results and Discussion....................................................................................................... 16 4.1 Partition Coefficient.................................................................................................. 16 4.2 Results....................................................................................................................... 17 5
Soil/Water Distribution Coefficient................................................................................... 20 5.1 Influence of Soil Types and Comparison to Literature Values.................................... 21 5.2 Migration Behavior................................................................................................... 22 5.3 Kd Summary.............................................................................................................. 24 6
Conclusions....................................................................................................................... 26 7
References......................................................................................................................... 27 8
Attachments...................................................................................................................... 28 Field Logs........................................................................................................ 28 Laboratory Kd Results..................................................................................... 28 Figure 1 Oyster Creek Generating Station location..................................................................... 7 Figure 2 Sample Locations.......................................................................................................... 8 Figure 3 Sr-85/90 and Cs-137................................................................................................... 19
RSCS TSD 24-103 Page 2 of 31 Distribution Coefficient (Kd) of Radionuclides in Soil Samples from the Oyster Creek Generating Station Figure 4 Co-60 and Am-241...................................................................................................... 20 Figure 5 Annual Distance of Contaminant Migration vs Kd....................................................... 24 Table 1 Details on Sampling from GHD Boring Logs and Laboratory Reports........................... 11 Table 2 Selected Radionuclides................................................................................................. 12 Table 3 Radiological Analysis Method and Tracer..................................................................... 14 Table 4 Summary of Kd Results................................................................................................. 17 Table 5 Comparison to Literature: Sand and Loam/Clay Soils................................................... 21 Table 6 Comparison of GEL results to OCGS Proposed Dose Modelling Values........................ 25
RSCS TSD 24-103 Page 3 of 31 Distribution Coefficient (Kd) of Radionuclides in Soil Samples from the Oyster Creek Generating Station 1 Introduction Radiation Safety and Control Services (RSCS) has prepared this Technical Services Document providing laboratory-measured soil partitioning coefficients for selected radionuclides at the request of the Oyster Creek Generating Station (OCGS) in Oyster Creek, New Jersey (the Site).
The soil partition coefficients (Kds) are used to evaluate the potential migration of radionuclides in groundwater at the Site. The Site location is shown in Figure 1.
2 Partition Coefficient The fate and transport of radionuclides in the subsurface are a serious concern due to their potential impact on the environment. In soils, these reactive substances undergo complex interactions based on the soil properties, the type of clay minerals, and pore-fluid parameters.
The distribution of a contaminant in soil and groundwater is influenced by the chemical characteristics and the properties of the surrounding soil and groundwater. The subsurface geology at OCGS includes various types of soil materials including sands, clay, and marl [1].
Contaminant sorption process of different solutes in the soils is generally described using isotherms. Sorption isotherms describe the concentration of the sorbed solute to the sorbent concentration at equilibrium. Several linear and nonlinear isotherms are commonly used in various fields of research to understand the sorption mechanism between sorbent (soil solids) and solute. The most common method for evaluating soil-groundwater partitioning of solutes is based on the partition coefficient Kd, which quantifies distribution of a contaminant between the sorbed solute to the sorbent in the solid and aqueous phases. Kd is an empirical measure that accounts for various chemical and physical mechanisms influencing this partitioning.
As Kd is a chemical property determined by valence electron configuration and is generally unaffected by atomic mass or nuclear emissions, it is assumed that all isotopes of an element have the same Kd value. Dose modeling accounts for the ingrowth of daughter products and
RSCS TSD 24-103 Page 4 of 31 Distribution Coefficient (Kd) of Radionuclides in Soil Samples from the Oyster Creek Generating Station the change in characteristics due to a different element with differing Kds. Key factors influencing Kd values in typical soil-groundwater systems include:
the soils cation exchange capacity (CEC),
pH, temperature, ionic strength, and the concentration of contamination in groundwater.
Kd is not determined by specific physical or chemical processes but rather by the overall interaction between dissolved constituents and the solid phase through which the water flows.
Kd values vary depending on the soils characteristics as the Kd is used to assess the degree to which a chemical species will be removed from a solution as the fluid passes through different soil media. In general, sands typically exhibit lower Kd values compared to silty sands and sandy till [2]. In wetland sediment soils Kd values can fluctuate due to factors such as bacterial growth, organic matter, and mineral content [3].
Realistic, site-specific solute/soil-related Kds are needed to accurately assess environmental risk. Soil and groundwater samples taken from various locations around the site from each soil type (generally referred to as sandy fill, sand, and sandy, silty clay/marl) are used to determine the Kd for select radionuclides in the various saturated zone types. These results can inform models with parameters that provide accurate predictions of transport and concentrations in the subsurface.
The justification for the Kd concept is generally acknowledged to be based on expediency in modeling and averaging the effects of attenuation reactions. Major difficulties exist in the interpretation, application, and meaning of laboratory-determined Kds relative to action real conditions. The laboratory method assumes equilibrium conditions that may not occur in the natural environment. Due to limited data, the laboratory study assumes that the distribution coefficients of the selected radionuclides are linear. This may not be true due to time-dependence, chemical kinetics, biological conditions, particle size distribution, or molecular structure.
3 Data Quality Objectives Sample Locations The objective of sampling and analysis is to obtain data of sufficient quality to adequately characterize Kds associated with saturated zone soils representative of the OCGS stratigraphy identified in the Conceptual Site Model [1]. Subsurface soil in the fill and native soils of the
RSCS TSD 24-103 Page 5 of 31 Distribution Coefficient (Kd) of Radionuclides in Soil Samples from the Oyster Creek Generating Station OCGS site were collected from two soil borings, labeled EDG and NOCA, and submitted to GEL Laboratories in Charleston, South Carolina, for Kd analysis for the following elements:
- Iron,
- Cobalt, and
- Americium The two soil boring locations used to collect samples are shown in Figure 2. The surficial geology at the OSGS consists of Teriary-Age coastal plain deposits comprised of sand, gravel, clay, and marl dipping slightly to the southeast. The topography at the OCGS Site is relatively flat, ranging from 10 to 23 feet above mean sea level [1]. The South Branch Forked River and Oyster Creek encircle the north, west and south sides of the site and drain to a tidal waterway nearly two miles east of the generating station. Cooling water for the OCGS is drawn from the South Branch Forked River and discharged to Oyster Creek via intake and discharge pipes at the west side of the developed portion of the Site [1].
Subsurface soil at the site consists of the following formations [1]:
- Fill: A medium-to fine-grained sand with trace to some silt. Based on the description of the fill, the majority of the fill appears to be excavated and backfilled Cape May Formation material generated when the Site was developed. Some clay and marl from beneath the Cape May formation excavated during construction may be present in the fill material. The fill thickness from soil boring logs varies from 0 feet to 38 feet below ground surface (bgs). The maximum fill thickness is estimated to be 53 feet in the vicinity of the Reactor Building, based on the depth of the excavation necessary for the building.
- Cape May Formation: A late Pleistocene accumulation of fine to medium sand and gravel marine deposits, formed when sea-level was higher than it is today. It is generally poorly compacted and may contain fossils. The Cape May Formation at the Site varies from 0 feet to 21.5 feet thick, thinner in areas where soil was excavated for development of the Site. The thickness of the Cape May Formation where it has not been excavated generally ranges from 17 feet to 20 feet.
- Upper Clay: A hard, gray, plastic organic clay containing inclusions of dense fine-grained sand with trace to some organic silt. The deposits of fine sand within the Upper Clay layer have high relative densities and are believed to be in the form of lenses or inclusions. Some boring logs describe the sand lenses as the dominant feature over a 1-foot to 5-foot thickness. In the area southwest of the Turbine
RSCS TSD 24-103 Page 6 of 31 Distribution Coefficient (Kd) of Radionuclides in Soil Samples from the Oyster Creek Generating Station Building, approximately half of the total thickness of the Upper Clay is silty sand. The Upper Clay is approximately 15 feet to 18 feet thick where not impacted by excavation. Information from outside the study area (boring logs from the area west of the intake and discharge canals and data from the Route 9 area) suggests a thinning trend from east to west.
- Cohansey Formation: A Late Miocene/Early Pliocene accumulation of medium to coarse-grained arkosic quartz sand (well stratified and cross-bedded) with trace to some silt, with thin clay lenses and quartz and quartzite pebble conglomerate. The unit represents a range of sedimentary environments ranging from fluvial to transitional marine environments (swamps, deltas, lagoons, beach sand, and shallow open marine shelf). Sediments at the base of the Cohansey appear to fill broad fluvial channels carved downward into the underlying formations. Many beds within the unit are heavily cemented by iron. All fossil material appears to be leached out of the Cohansey. The Cohansey formation is approximately 80 feet thick at the Site.
- Lower Clay: The lower clay is a dense gray medium to fine-grained sand containing a trace to some organic silt and layers or inclusions of hard gray organic clay. The thickness of the lower clay is estimated to be on the order of 10 feet to 20 feet.
- Kirkwood Formation: A Middle Miocene medium to fine-grained sand with trace silt.
The thickness at the Site is unknown but, based on deep water supply wells drilled in the area, it extends to depths on the order of 500 feet and more.
Six soil samples were collected for Kd analysis from the upper water-bearing units: the Fill (one sample from each boring location), the Cape May Formation, the upper clay, the Cohansey Formation, and the lower clay as discussed below.
RSCS TSD 24-103 Rev 0 Page 7 of 31 Distribution Coefficient (Kd) of Radionuclides in Soil Samples from the Oyster Creek Generating Station Figure 1 Oyster Creek Generating Station location
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RSCS TSD 24-103 Page 8 of 31 Distribution Coefficient (Kd) of Radionuclides in Soil Samples from the Oyster Creek Generating Station Figure 2 Sample Locations Monitoring Well o
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RSCS TSD 24-103 Rev 0 Page 9 of 31 Distribution Coefficient (Kd) of Radionuclides in Soil Samples from the Oyster Creek Generating Station 3.1 Field Sampling Process Two samples were collected from each of the three formations using two borings advanced at the Site. Soil borings were advanced using a sonic drill rig equipped with a 4-inch sampling barrel on May 15 and 16, 2024.
Soil boring EDG was advanced on the west side of the developed portion of the Site, 15-feet southeast of the Emergency Diesel Building and 100-feet east of the discharge canal (Figure 2).
Soil boring NOCA was advanced on the area between north of the developed portion of the Site, approximately 450 feet west of Route 9 and 625 feet south of the South Branch Forked River (Figure 2). Approximately 1 kilogram of soil was collected from each targeted subsurface strata (Fill, Cape May Formation, Cohansey Formation) based on field observations.
To facilitate a general understanding of Kds through the interaction of various soil types, the soil samples were separated into three general categories: Fill, Cape May Formation, and Cohansey Formation. Portions of all soil samples collected were submitted for Particle Size Analysis (Sieve and Hydrometer Testing) to SGS North America, Inc. of Dayton, New Jersey. The two samples collected from the Fill were identified as Loamy Sand and Sandy Loam. The two samples collected from the Cape May Formation were identified as Sandy Clay Loam and Sandy Loam. The two samples collected from the Cohansey Formation were identified as Sand and Loamy Sand (Table 1).
Soil sample details are summarized in Table 1 and boring logs are included in Attachment 1.
The locations of the soil borings and monitoring wells are indicated on Figure 2 and sample details including sampled formations and corresponding water samples are presented in Table
- 1.
A total six soil samples were utilized for the Kd testing:
- Two fill samples, one from each soil boring (NOCA/EDG)
- Two Cape May Formation samples, one from each soil boring (NOCA/EDG)
- Two Cohansey Formation samples, one from each soil boring (NOCA/EDG)
Water samples for use in the Kd analysis were collected from monitoring well W-6, which is screened in the Cape May Formation, and monitoring well MW-15K-1A, which is screened in the Cohansey Formation (Figure 2). Water sampled from well W-6 was used with soil samples collected from the Fill as well as with the samples collected from the Cape May Formation. The water sample from MK-15-1A was used for the samples collected from the Cohansey Formation.
Groundwater samples were collected into one-gallon containers, filled to capacity and included approximately 12 gallons for each monitoring well sample. The samples were refrigerated to limit biological changes. Chain-of-custody procedures were followed throughout the sample
RSCS TSD 24-103 Page 10 of 31 Distribution Coefficient (Kd) of Radionuclides in Soil Samples from the Oyster Creek Generating Station collection process and transferred to the laboratory to ensure that the integrity of the samples was maintained.
RSCS TSD 24-103 Rev 0 Page 11 of 31 Distribution Coefficient (Kd) of Radionuclides in Soil Samples from the Oyster Creek Generating Station Table 1 Details on Sampling from GHD Boring Logs and Laboratory Reports Borehole ID Date Depth of Borehole (feet)
Sample Depth (feet)
Sample ID Corresponding Water Sample Sampled Formation USDA Soil Texture, from Particle Size Analysis Description of Materials from Boring Logs EDG 15 May 2024 50 1.5 - 5 O-1197486-EDG-FILL-(1-5)-051524-DZB-01 W-6 Cape May Ground Water Fill Loamy Sand Light gray, fine to medium to coarse SAND, no clay, trace silt 8 - 13 SO-1197486-EDG-CM-(8-13)-
051524-DZB-02 W-6 Cape May Ground Water Cape May Formation Sandy Clay Loam Yellow, fine to medium SAND, trace silt, dry, yellow 45 - 50 SO-1197486-EDG-CO(45)-
051524-DZB-03 MW-15K-1A Cohansey Ground Water Cohansey Formation Sand Tan, loose, fine to medium SAND, trace silt NOCA 16 May 2024 50 7 - 13 SO-1197486-NOCA-FILL-(7-13)-051624-DZB-04 W-6 Cape May Ground Water Fill Sandy Loam Black, CLAYEY SAND, some silt, and Black, CLAY, with fine to medium sand and silt 20 - 25 SO-1197486-NOCA-CM-(20-25)-
051624-DZB-05 W-6 Cape May Ground Water Cape May Formation Sandy Loam Light tan/Yellow, fine to medium SAND, with silt, trace clay 38 - 40 SO-1197486-NOCA-CO-(38-40)-
051624-DZB-06 MW-15K-1A Cohansey Ground Water Cohansey Formation Loamy Sand Light gray, fine SAND, with silt, trace clay
RSCS TSD 24-103 Page 12 of 31 Distribution Coefficient (Kd) of Radionuclides in Soil Samples from the Oyster Creek Generating Station
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3.2 Analysis Parameters The OCGS includes a Conceptual Site Model that indicates that Target radionuclides were not detected at concentrations greater than their respective LLD in the groundwater and surface water samples collected. The potential target radionuclides were refined to select six radionuclides that were representative of the potential target radionuclides. The six radionuclides were selected based on the following criteria:
- 1) Contaminants of Potential Concern (COPCs) with relatively high mobility in the environment (i.e., low soil partition coefficient),
- 2) COPCs that have been identified as having the potential for release, and
- 3) COPCs that are assumed to be present in fission product waste in relatively high abundance.
The resulting selection is listed in Table 2.
Table 2 Selected Radionuclides Isotope Criterion for Selection Technecium-99 high mobility/long half-life Strontium 85/90 Low-mid mobility/ present in fission product Cesium 137 Low-mid mobility/ present in fission product Iron-55 Low-mid mobility/ present in fission product Cobalt-60 Low mobility/present in fission product Am-241 Low mobility/present in fission product As a result, the requested radionuclides for the Kd study were Technecium-99 (Tc-99), Strontium-90 (Sr-90), Cesium-137 (Cs-137), Iron-55 (Fe-55), Cobalt-60 (Co-60) and Americium-241 (Am-241).
Note: Strontium-85 (Sr-85) is used by the laboratory as a surrogate for Sr-90.
3.3 Laboratory Experiment and Sample Analysis The collected six soil and corresponding groundwater samples were shipped to GEL Laboratories in Charleston, South Carolina for determination of the Kd in accordance with ASTM C1733-21 [4].
The full laboratory narrative with supporting documents and appendices has been provided to
RSCS TSD 24-103 Page 13 of 31 Distribution Coefficient (Kd) of Radionuclides in Soil Samples from the Oyster Creek Generating Station Oyster Creek as a separate submission. A summary of laboratory results can be found in the Appendices.
Consistent with ASTM C1733-21, the chemical species in the solid and liquid phases was placed in contact with one another. The Kd was experimentally determined by periodically quantifying the distribution of the radionuclide in the soil and representative groundwater. Groundwater samples were spiked with tracers to ascertain the time required for the tracer/soil to achieve constant solution concentrations.
The samples were received by the laboratory on June 20, 2024, within the required preservation temperature (<6 ° C) to retard biological growth. Since Kd analysis is a function of pH, acid preservation was not used during the sample collection. The sample receipt noted that the samples were received intact, as received.
Each groundwater sample was received by GEL in 2.5-gallon cubitainers totaling 12 gallons. The initial pH of each groundwater was recorded and corrected to 250C. Due to the presence of sedimentation, the water was filtered through a 0.7 µm borosilicate glass filter and the filtrate was used for the analyses. The soils were sieved through a #10 sieve to remove gravel-sized grains larger than 2 mm. The mass fraction of the material greater than 2 mm was recorded and the Kd result was normalized to account for the missing mass. The moisture content of the soil was performed to determine the dry weight equivalent for a 25:1 liquid-to-soil mass ratio.
The contact solutions with the desired analytical tracer were prepared from each groundwater based upon the analysis method i.e. liquid scintillation or gamma spectroscopy (Table 3). The laboratory control spikes (LCS) were added to the solution prior to digestion. Test samples were taken over several time intervals to determine the time required to attain constant solution concentrations of the test species in the solution.
During the time interval testing, pH levels were observed to decrease in three of the samples from near neutral to values in the 2 to 3 range. The three samples (NOCA Fill, Cape May lower clay, and Cohansey lower clay) and the remaining three samples were buffered after the initial 28 days of testing to more neutral pH values as allowed by ASTM C1733-21 Method [4]. The samples were allowed to equilibrate for an additional 26 days and pH levels quickly returned to near-neutral levels. Lower pH typically drives Kd to lower values, indicating stabilization in the liquid phase.
The final pH of the samples was in the near neutral range for all samples.
Because Sr-90 is a beta-only emitter, Sr-85, a gamma emitter, was used as a surrogate in the analysis. Sr-85s gamma emission allowed for the concentration of Sr to be monitored using
RSCS TSD 24-103 Page 14 of 31 Distribution Coefficient (Kd) of Radionuclides in Soil Samples from the Oyster Creek Generating Station gamma spectroscopy. Because Kd is based upon chemical behavior, using the Sr-85 surrogacy did not impact the Kd analysis.
Table 3 Radiological Analysis Method and Tracer Analyte Method Tracer Into 3L of each groundwater sample Tc-99 Liquid Scintillation Spectroscopy (LSC) 500 pCi/ml Tc-99 500 pCi/ml Fe-55 Fe-55 Sr-85 500 pCi/ml Cs-137, Sr-85, Co-60 Am-241 Cs-137 Co-60 Gamma Spectroscopy Am-241 At prescribed intervals, an aliquot for each sample was taken and analyzed per the defined method. Once the samples reached equilibrium, the final Kd test was analyzed.
3.3.1 Liquid Scintillation A 5 mL aliquot of each sample was analyzed by liquid scintillation counting. The aliquot was placed into a liquid scintillation vial and 15 ml of scintillation cocktail was added. The sample vials were inspected before counting to ensure homogeneity of the scintillation fluid with the sample and each sample set was dark adapted for at least 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> before counting. The samples were counted on a liquid scintillation counter programmed to count only the Tc-99 and Fe-55 regions of interest.
The liquid scintillation counter Tc-99 program was standardized using Tc-99 as the radioisotope to establish a specific efficiency quench curve. For all liquid scintillation analyses, the daily instrument performance checks were within the running statistical control limits. The samples were counted for 10 minutes each.
3.3.2 Gamma Spectroscopy For gamma spectroscopy, 5 mL of each sample was counted in a 20-mL polyethylene vial using a geometry directly on the detector. The 5 mL volume was used to reduce dead time and maintain good sensitivity. The daily gamma calibration blanks and check standards were within control limits. The gamma detector's monthly background was within date. The samples were counted for ten minutes each.
RSCS TSD 24-103 Page 15 of 31 Distribution Coefficient (Kd) of Radionuclides in Soil Samples from the Oyster Creek Generating Station 3.4 Quality Assurance Reference solutions were made using the two ground water sample types (Appendix 2). As anticipated, the addition of acid-preserved standards lowered the pH of the groundwater samples, which was then adjusted back to the original pH using 6M NaOH.
Isotope recoveries were comparable with the estimated spiked values with the exceptions of americium and iron (Attachment 2). Americium and other transuranic elements stored without preservation can be absorbed into container walls over time and this is a potential cause of the 63% average recovery. Samples and associated references used the same type of containers during the study, so it appears the impact of absorption was comparable between the reference and samples as shown in the Kd values determined.
Iron was also low compared to the spiked value at an average of 51% (Attachment 2). This low recovery could have been caused by precipitation of iron in the ground water which was "ltered during each sample collection. Since samples and references had similar "ltration processes, the impact of the low iron yields was replicated between sample and reference and should not negatively impact Kd values.
RSCS TSD 24-103 Page 16 of 31 Distribution Coefficient (Kd) of Radionuclides in Soil Samples from the Oyster Creek Generating Station 4 Results and Discussion 4.1 Partition Coefficient Consistent with ASTM C1733-21 Kd values were calculated using the following equation [4]:
Equation 1: Kd based on Tracer Starting Concentration (Kd)
=
(x ) (x )
Where:
Kd
= Distribution coefficient, mL/g V
= Volume of tracer solution, mL Cs
= Starting concentration of tracer in solution, pCi/mL Cf
= Final concentration of tracer in solution after reacting with soil, pCi/mL M
= Dry mass of solid, g
RSCS TSD 24-103 Page 17 of 31 Distribution Coefficient (Kd) of Radionuclides in Soil Samples from the Oyster Creek Generating Station 4.2 Results A laboratory replicate was created for each of the groundwater-soil sample pairs. GEL analyzed the sample and the duplicate and calculated the Kd. The Kd Data Sheets containing all data used for the final Kd calculations for each sample replicate are presented in Appendix 2. The Kd values presented are the average of the duplicate Kd results. The results are a summarized in Table 4.
The full list of Kd results is provided in Appendix 2.
Table 4 Summary of Kd Results Tc-99 Sr-85 Fe-55 Cs-137 Co-60 Am-241 Formation/Sample Location Kd (ml/g)
Kd (ml/g)
Kd (ml/g)
Kd (ml/g)
Kd (ml/g)
Kd (ml/g)
Fill (EDG) 0.07 30 372 996 2591 1260 Cape May Fm 0.38 41 326 1138 6607 5129 Cape May Fm (lower clay layer) 5.75 390 970 3488 5068 4695 Fill (NOCA) 48 449 911 3180 6960 6646 Cohansey Fm 0.10 2.04 89 7
77 724 Cohansey Fm (lower clay layer) 54 448 164 4841 4849 5655 The results of the Kd analysis are included in Table 4 where all six samples are shown for each of the six radionuclides. The Kd results included in Table 4 show that Tc-99 and Sr-90 typically have the lowest Kd values and Am-241 and Co-60 are associated with the highest Kd values. This indicates that Tc-99 and Sr-90 will move faster in groundwater relative to Fe-55, Cs-137, Co-60 and Am-241. The Kd results also demonstrate that the Cohansey Formation is associated with the
RSCS TSD 24-103 Page 18 of 31 Distribution Coefficient (Kd) of Radionuclides in Soil Samples from the Oyster Creek Generating Station lowest Kd values and COPCs will migrate faster in the Cohansey Formation relative to the other soils at the Site Table 4.
The correlation of the various radionuclide Kds was also evaluated. Sr-85/90 versus Cs-137 and C0-60 versus Am-241 are shown to be well correlated (and R² = 0.8921 0
1000 2000 3000 4000 5000 6000 0
50 100 150 200 250 300 350 400 450 500 Cs-137 ml/g Sr-85/90 ml/g Sr-85/90 vs Cs-137 j
I
t---~_j_
RSCS TSD 24-103 Page 19 of 31 Distribution Coefficient (Kd) of Radionuclides in Soil Samples from the Oyster Creek Generating Station Figure 4). The coefficient of correlation (R2) between each pair is close to 0.9. The relatively high degree of correlation between Sr-85/Cs-137 and Co-60/Am-241 suggests a common sorption mechanism for the two radionuclide pairs.
Figure 3 Sr-85/90 and Cs-137 R² = 0.8921 0
1000 2000 3000 4000 5000 6000 0
50 100 150 200 250 300 350 400 450 500 Cs-137 ml/g Sr-85/90 ml/g Sr-85/90 vs Cs-137 I
RSCS TSD 24-103 Page 20 of 31 Distribution Coefficient (Kd) of Radionuclides in Soil Samples from the Oyster Creek Generating Station Figure 4 Co-60 and Am-241 5 Soil/Water Distribution Coefficient A significant mechanism for degraded groundwater quality is most likely due to the leaching of contaminants from unsaturated soils into the groundwater. Once the COPCs have dissolved in the groundwater, they will be transported with groundwater flow and will be retarded by any soil-groundwater partitioning. The soil-groundwater partitioning is based upon the partition R² = 0.8658 0
1000 2000 3000 4000 5000 6000 7000 0
1000 2000 3000 4000 5000 6000 7000 8000 Am-241 (ml/g)
Co-60 (ml/g)
RSCS TSD 24-103 Page 21 of 31 Distribution Coefficient (Kd) of Radionuclides in Soil Samples from the Oyster Creek Generating Station coefficient, Kd. The Kd will impact both infiltration/leaching and soil-groundwater partitioning behavior.
5.1 Influence of Soil Types and Comparison to Literature Values The type of soil also has an impact soil-groundwater partitioning and Kd. As shown in several studies sand-rich soils typically are associated with lower Kd values relative to loam, silt and clay-rich soils [2]. A summary of Kd values for the six radionuclides in sand and loam/clay soils is compared to the range of Kd values measured in this study (Table 5).
Consistent with the results from this study, Tc-99 and Sr-85/90 Kd values are significantly lower relative to Fe-55, Cs-137, Co-60 and Am-241. Likewise, sand-bearing samples for each radionuclide are consistently lower relative to Kds from clay/loam soils (Table 4 and Table 5).
The comparison to literature values demonstrates the difference for Kd in sand samples relative to more complicated soils. The results from the GEL study are consistent with the range of Kd values identified in the literature. The presence of silts and clays in the soil samples increases the Kd and enhances partitioning to the solid phase, ultimately limiting the mobility of the radionuclides (Table 5). This behavior demonstrates the need for site-specific Kd values and a clear understanding of the soil type where a Kd will be utilized.
Table 5 Comparison to Literature: Sand and Loam/Clay Soils Literature (mL/g)
Tc-99 Sr-85/90 Fe-55 Cs-137 Co-60 Am-241 IAEA 2010 (Sand)1 0.23 22 320 530 640 1000 Sheppard & Thibault 1990 (Sand)2 0.10 15 220 280 60 1900 Rowan and Carr 2016 (Sand)3 N/A 77 260 1200 2400 2200 IAEA 2010 (Loam/Clay)1 N/A 69 1100 370 3800 4300 Sheppard & Thibault 1990 (Clay)2 1.00 110 5100 1900 550 8400 This Study 0.07-54 2.04-449 89-970 7-4841 77-6960 724-6646 Note 1 - Reference [3] IAEA, "Handbook of Parameter Values for the Prediction of Radionuclide Transfer in Terrestrial and Freshwater Environments," International Atomic Energy Agency, 2010.
Note 2 - Reference [2] M. Sheppard and D. Thibault, "Default Soil Solid/Liquid Partitioning Coefficients, Kds, fo Four Major Soil Types: A Compendium," Health Physics, Vols. Vol 59, No. 4, pp. 471-482, October 1990.
Note 3 - Reference [4], "Site-specific soil Kd for the environment near CANDU reactors," CANDU Owners Group Inc., 2016.
RSCS TSD 24-103 Page 22 of 31 Distribution Coefficient (Kd) of Radionuclides in Soil Samples from the Oyster Creek Generating Station 5.2 Migration Behavior The Kd values determined for the six radionuclides included in the study indicate that Tc-99 and Sr-90 have relatively low Kds and that Cs-137, Fe-55, Co-60 and Am-241 have much greater Kd values (Table 4 and Table 5). The lower Kd values give rise to enhanced migration potential for Tc-99 and Sr-90 relative to Cs-137, Fe-55, Co-60 and Am-241. The site studies conducted at OCGS are consistent with these relationships. Tritium has no retardation and effectively flows with groundwater and is observed in groundwater throughout the site. The higher Kd values associated with Fe-55, Co-60, Cs-137 and Am-241 indicate that these radionuclides have experienced limited migration and are located near or within the source area(s).
The relationship between radionuclide migration potential and Kd is illustrated Figure 7. Figure 7 is constructed by calculating groundwater flow velocity using Darcys Law (seepage velocity) and aquifer properties for the Site. Groundwater flow velocities in porous media can be calculated using the modified Darcys equation accounting for porosity to provide linear flow velocities (Vgw):
Equation 2: Modified Darcys Equation gw = (*/)/
Where:
K
= the hydraulic conductivity of the porous medium,
/ = the hydraulic gradient provided by the change in the hydraulic head () over distance
(),
n
= the porosity of the porous medium.
Based on site studies at OCGS maximum groundwater velocities for the Cape May and Cohansey Formations are 1.5 m/day and 0.46 m/day, respectively [6].
Combining Equation 2 with Equation 3 allows calculation of contaminant velocity.
Equation 3: Retardation Equation
/w= 1/(1(+/*K))
RSCS TSD 24-103 Page 23 of 31 Distribution Coefficient (Kd) of Radionuclides in Soil Samples from the Oyster Creek Generating Station Where:
w =groundwater velocity
=contaminant velocity in groundwater
= the dry bulk density of the aquifer (1.6 g*cm-3 for local sands),
n
= the porosity (0.25 in sand) [6], and Kd
= the distribution coefficient (mL/g).
Using these two equations (Equations 2 and 3), values of annual contaminant migration are shown as a function of Kd. The Kd values developed as part of this study are also summarized in Figure 7. Based on this evaluation, Sr-90 has a Kd ranging from 2 to 449 mL/g and the Tc-99 Kd ranges from 0.07 to 54 ml/g (Table 4). Both of these radionuclides will have limited migration potential on the order of several metres per year (m/a) depending on which soil type they are associated, while based on the greater Kd values, Fe-55, Co-60, Cs-137, and Am-241 are typically restricted to less than 0.1 m/a. As these estimated migration rates only represent horizontal flow within saturated groundwater, the time required to reach the water table via infiltration processes may also be significant for radionuclides with elevated Kds. Based on these relationships, most of the radionuclide waste with elevated Kds (i.e., Kd >100 mL/g) is expected to be within or very near the historic source area(s).
RSCS TSD 24-103 Rev 0 Page 24 of 31 Distribution Coefficient (Kd) of Radionuclides in Soil Samples from the Oyster Creek Generating Station
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Figure 5 Annual Distance of Contaminant Migration vs Kd 5.3 Kd Summary The Kd values determined for sands and the impacts on Kd values for sandy soils from the presence of silt and clay soils determined in the GEL study are consistent with literature values. The presence of silt and clay act to increase Kd values relative to sandy soil Kds (Table 4 and Table 5). Based on these relationships, RSCS recommends that the Kd values determined in the GEL study should be carefully utilized with the specific soil types at OCGS.
The results of the site-specific Kd study are also compared to the NRC-published Kd distributions used in the probabilistic analysis and DCGL development at the site (Table 6). Table 6 presents a comparison of the site-specific values to NRC-published distributions and 25th and 75th percentile values.
The results of the Kd study show:
0 2
4 6
8 10 12 0
100 200 300 400 500 600 700 800 900 1000 Annual Distance (m)
Kd mL/g Annual Distance of Contaminant Migration vs Kd Cape May 1800 ft-yr Cohansey 550 ft-yr Vc=Vgw/(1+/n*K r
I IU IU
RSCS TSD 24-103 Page 25 of 31 Distribution Coefficient (Kd) of Radionuclides in Soil Samples from the Oyster Creek Generating Station Agreement for Sr-85, Cs-137, and Fe-55: the site-specific Kd ranges for Sr-85 and Cs-137 fall within the ranges of the published distributions and the 25th and 75th percentile values used in the probabilistic analysis and DCGL development fall within the site-specific Kd ranges. For Fe-55, the published Kd value falls within the site-specific range.
Agreement for Tc-99: the site-specific range is not totally captured within the published range and the 25th percentile value (0.019) is a lower value than the low end of the site-specific range for Tc-99 (0.07).
For Co-60 and Am-241: the site-specific ranges are captured within the published ranges, but the 25th percentile values (37.1 for Co-60 and 269 for Am-241) are lower values than the low ends of the site-specific ranges (77 for Co-60 and 724 for Am-241).
The use of the 25th percentile values for Tc-99, Co-60 and Am-241 does not raise a modeling issue because the 25th percentile values increase the conservatism in the mobility of these ROCs in soil over that indicated by the respective site-specific ranges. The results from the site-specific Kd study indicate that the use of the published distributions and the 25th and 75th percentile values from those distributions was appropriate for modeling the OCGS site.
Table 6 Comparison of GEL results to OCGS Proposed Dose Modelling Values and 25th and 75th Percentile Values Tc-99 Sr-85 Fe-55 Cs-137 Co-60 Am-241 Kd (ml/g)
Kd (ml/g)
Kd (ml/g)
Kd (ml/g)
Kd (ml/g)
Kd (ml/g)
Range of GEL Study 0.07-54 2.04-449 89-970 7-4841 77-6960 724-6646 OCGS Proposed Dose Modelling 0.001-1.18 0.089-5460 321 2.16-131000 0.036-191000 2.93-33600 Value assigned if Kd found to be risk-sensitive 0.019 (25th percentile) 73 (75th percentile) 6.58 (25th percentile)
Kd not found to be risk-sensitive 158 (25th percentile) 1800 (75th percentile) 37.1 (25th percentile) 3700 (75th percentile) 269 (25th percentile)
RSCS TSD 24-103 Page 26 of 31 Distribution Coefficient (Kd) of Radionuclides in Soil Samples from the Oyster Creek Generating Station 6 Conclusions A total of six soil samples were collected from two soil borings (NOCA and EDG) located at unimpacted areas at OCGS. Groundwater was sampled from two existing monitoring wells that were screened within the Cape May (W-6) and Cohansey Formations (MW-15K-1A) The six soil/groundwater samples utilized for the Kd testing included:
Two fill samples, one from each soil boring (NOCA/EDG)
Two Cape May Formation samples, one from each soil boring (NOCA/EDG)
Two Cohansey Formation samples, one from each soil boring (NOCA/EDG)
The collected soil and groundwater samples were shipped to GEL Laboratories, Charleston, SC for measurement of the Kd in accordance with ASTM C1733-21 [6]. The samples were received by the laboratory on June 20, 2024.
The Kd results from the GEL study-show that Tc-99 and Sr-90 typically have the lowest Kd values and Am-241 and Co-60 are associated with the highest Kd values. This indicates that Tc-99 and Sr-90 will move faster in groundwater relative to Fe-55, Cs-137, Co-60 and Am-241. The Kd results also demonstrate that the Cohansey Formation is associated with the lowest Kd values and COPCs will migrate faster in the Cohansey Formation relative to the other soils at the Site.
The comparison to literature values demonstrates the difference for Kd in sand samples relative to more complicated soils. The results from the GEL study are consistent with the range of Kd values identified in the literature and the impacts of silt and clay material in the soils (Table 5).
The presence of silts and clays in the soil samples increases the Kd and enhances partitioning to the solid phase, ultimately limiting the mobility of the radionuclides (Table 5).
The six radionuclides included in the GEL study are compared to the range of Kds proposed by OCGS for dose modelling and are consistent with the range proposed dose modelling (Table 6).
RSCS TSD 24-103 Page 27 of 31 Distribution Coefficient (Kd) of Radionuclides in Soil Samples from the Oyster Creek Generating Station 7 References
[1] Holtec Decommissioning International, "Hydrogeologic Investigation Report Oyster Creek Generating Station," 2022.
[2] M. Sheppard and D. Thibault, "Default Soil Solid/Liquid Partitioning Coefficients, Kds, fo Four Major Soil Types: A Compendium," Health Physics, Vols. Vol 59, No. 4, pp. 471-482, October 1990.
[3] IAEA, "Handbook of Parameter Values for the Prediction of Radionuclide Transfer in Terrestrial and Freshwater Environments," International Atomic Energy Agency, 2010.
[4] R. Carr, "Site-specific soil Kd for the environment near CANDU reactors," CANDU Owners Group Inc., 2016.
[5] GHD, "Hydrogeologic Investigation Report OCGS, Forked River New Jersey," 2020.
[6] ASTM C1733-21, "Standard Test Method for Distribution Coefficients of Inorganic Species by Batch Method," 2021.
[7] Rowan, D.J., Re-evaluation of soil to water partitioning coefficients for the Chalk River Site, EWT-23-000, 2023.
[8] D. Rowan, Re-evaluation of soil to water partitioning coefficients for the Chalk River Site, 153-121240-401-000, EWT-24-025, 2024.
RSCS TSD 24-103 Page 28 of 31 Distribution Coefficient (Kd) of Radionuclides in Soil Samples from the Oyster Creek Generating Station 8 Attachments Field Logs Laboratory Kd Results
RSCS TSD 24-103 Page 29 of 31 Distribution Coefficient (Kd) of Radionuclides in Soil Samples from the Oyster Creek Generating Station Field Logs
0 0
40 117 240 0
1 0
0 0
STONE (FILL)
SP-Brown, medium to coarse SAND, little silt, some gravel, trace cobbles, dry (FILL)
SP-Light gray, fine to medium to coarse SAND, no clay, trace silt (FILL)
SP-Yellow, fine to medium SAND, trace silt, dry (CAPE MAY FORMATION)
- hard at 6.00ft BGS CL-Brown, soft, CLAY, with silt, some fine to medium sand, wet (CAPE MAY FORMATION)
SP-Gray, loose, fine SAND, trace silt, moist (CAPE MAY FORMATION)
SP-Tan, dense, fine SAND, trace silt, moist, slight hydrocarbon odor (CAPE MAY FORMATION)
SP-Gray, hard, CLAY, some Silt, trace fine sand, no odor SP-Gray, hard, CLAY, some Silt, trace fine sand, no odor SC-Gray, hard, CLAYEY SAND, some silt, no odor SP-Gray, hard, fine SAND, with clay, some silt, no odor CL-Gray, hard, CLAY, with sand, some silt, no odor SP-Tan, loose, fine to medium SAND, trace silt, no odor (COHANSEY FORMATION)
- with gravel at 40.00ft BGS
- no clay at 45.00ft BGS END OF BOREHOLE @ 50.00ft BGS 0.50 1.50 5.00 13.00 15.00 19.00 20.00 25.00 29.50 32.00 33.00 38.00 50.00 (OVERBURDEN)
Page 1 of 1 INTERVAL SAMPLE REC (ft)
NUMBER
'N' Value PID (ppm) 5 10 15 20 25 30 35 40 45 50 EDG STRATIGRAPHIC LOG HOLE DESIGNATION:
STRATIGRAPHIC DESCRIPTION & REMARKS MEASURING POINT ELEVATIONS MAY CHANGE; REFER TO CURRENT ELEVATION TABLE NOTES:
DATE COMPLETED: 15 May 2024 DRILLING METHOD: 4" Sonic FIELD PERSONNEL: Darren Basich DRILLER: Jason Kuni DEPTH ft BGS PROJECT NAME: CDI/Site Investigation-OCNGS PROJECT NUMBER: 11197486 CLIENT: Holtec LOCATION: Oyster Creek Nuclear Generating station - Oyster Creek, NJ DRILLING CONTRACTOR: Enviroprobe Services Inc.
File: \\\\GHDNET\\GHD\\US\\EDISON\\PROJECTS\\564\\11197486\\TECH\\GINT\\LOG DATABASE\\11197486 HOLTEC-OYSTER.GPJ Library File: GHD_ENVIRO_V04.GLB Report: OVERBURDEN LOG Date: 5/6/24 DEPTH BGS
~
f----------' I
.......-.*1
/}ii r-~-\\-.:~
~ I Cl
/I\\
~
r-::.. 7 l/.{}ll
~--: *.-::* :**
l---J ~
f&;:
~E---~
s ti lliiiiiiiiill
SP-Brown/black, fine to medium to coarse SAND, some silt, little clay, no odor (FILL)
SP-Black, hard, fine to medium SAND, trace clay, some silt, no odor (FILL)
SC-Black, CLAYEY SAND, some silt, no odor (FILL)
CL-Black/Dark gray, CLAY, with fine to medium sand and silt, no odor
- wet, no recovery at 15.00ft BGS SP-Light tan/Yellow, fine to medium SAND, with silt, trace clay (CAPE MAY FORMATION)
CL-Dark gray, hard, CLAY, trace fine sand, some silt, no odor SP-Light gray, fine SAND, with silt, trace clay, no odor (COHANSEY FORMATION)
- no recovery from 40.00 to 50.00ft BGS END OF BOREHOLE @ 50.00ft BGS 3.00 5.00 10.00 20.00 25.00 38.00 50.00 (OVERBURDEN)
Page 1 of 1 INTERVAL SAMPLE REC (ft)
NUMBER
'N' Value 5
10 15 20 25 30 35 40 45 50 NOCA STRATIGRAPHIC LOG HOLE DESIGNATION:
STRATIGRAPHIC DESCRIPTION & REMARKS MEASURING POINT ELEVATIONS MAY CHANGE; REFER TO CURRENT ELEVATION TABLE NOTES:
DATE COMPLETED: 16 May 2024 DRILLING METHOD: 4" Sonic FIELD PERSONNEL: Darren Basich DRILLER: Ken Lindes DEPTH ft BGS PROJECT NAME: CDI/Site Investigation-OCNGS PROJECT NUMBER: 11197486 CLIENT: Holtec LOCATION: Oyster Creek Nuclear Generating station - Oyster Creek, NJ DRILLING CONTRACTOR: Enviroprobe Services Inc.
File: \\\\GHDNET\\GHD\\US\\EDISON\\PROJECTS\\564\\11197486\\TECH\\GINT\\LOG DATABASE\\11197486 HOLTEC-OYSTER.GPJ Library File: GHD_ENVIRO_V04.GLB Report: OVERBURDEN LOG Date: 5/6/24 DEPTH BGS
- i!
qf4 r:*r:~1 ti lliiiiiiiiill
RSCS TSD 24-103 Page 30 of 31 Distribution Coefficient (Kd) of Radionuclides in Soil Samples from the Oyster Creek Generating Station - Laboratory Kd Results
Distribution Coefficient (Kd) Method Report November 22, 2024 Page 1 of 22 The ASTM C1733-21 standard test method is performed to determine the distribution coe icients (Kd) of inorganic species using a batch sorption technique. This method quanti"es the uptake of dissolved ionic species by solid materials, primarily for evaluating contaminant migration in soils or other solid substrates. The test provides critical information on the sorption properties of soils, helping to clarify contaminant behavior in environmental contexts.
On July 16, 2024, GEL received six soil and two groundwater samples from the Oyster Creek Nuclear Power Plant under laboratory work order 675837 for Kd determination. The samples were packaged, transported, and stored under cool conditions to minimize potential chemical changes in the matrices. GEL used its internal method RAD-A-074 to maintain samples over the duration of the study. Individual soil samples were paired to speci"c liquid phases as summarized in Table 1 below.
Table 1: Sample Receipt Summary Lab ID Sample Description Ground Water Parameters Requested Initial pH Initial %
Moisture 675837001 NOCA fill Cape May Am241, Cs137, Co60, Sr90, Fe-55, Tc-99, C-14 7.74 27.5 675837002 Cape May Reference Cape May Am241, Cs137, Co60, Sr90, Fe-55, Tc-99, C-14 7.74 675837003 Fill Sand Cape May Am241, Cs137, Co60, Sr90, Fe-55, Tc-99 7.74 8.2 675837004 Cape May Sand Cape May Am241, Cs137, Co60, Sr90, Fe-55, Tc-99 7.74 15.9 675837005 Cape May lower clay Cape May Am241, Cs137, Co60, Sr90, Fe-55, Tc-99 7.74 25.6 675837006 Cohansey Sand Cohansey Am241, Cs137, Co60, Sr90, Fe-55, Tc-99 7.08 13.3 675837007 Lower Clay Cohansey Am241, Cs137, Co60, Sr90, Fe-55, Tc-99 7.08 30.4 675837008 Cohansey Reference Cohansey Am241, Cs137, Co60, Sr90, Fe-55, Tc-99 7.08 A percent moisture determination was performed on the six as-received solid samples (see Table 1), while the two groundwater samples were "ltered to remove particulates greater than 0.7 µm.
The six soil samples were then equilibrated with their corresponding groundwater using two 15-minute agitation cycles on a magnetic stirring plate. After each rinse, the liquid was discarded, followed by a "nal 300 mL rinse conducted over 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />.
le] =I* I Laboratories LLc a member of The GEL Group INC 2040 Savage Road I Charleston, SC 29407 843.556.8171 gel.com
Distribution Coefficient (Kd) Method Report November 22, 2024 Page 2 of 22 An equilibrated percent moisture determination was performed on the treated, wet soil, with an aliquot taken to ensure a net dry weight (M in the equation below) of 18 grams for preliminary samples and 4 grams for the "nal samples. For equilibration, 440 mL of groundwater was added to the preliminary samples and 100 mL to the "nal samples (V in the Kd equation below). No extraneous material greater than 2 mm was removed from the samples, which was applied as F in Kd equation 1 below.
The Kd study began on August 12, 2024, with 12 preliminary sample collections concluding on October 30, 2024 (day 82). Samples were stirred on magnetic stirrers every 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> for 15 minutes, controlled by an automatic timer. After stirring, a 1-hour settling period was allowed before collecting a 5 mL "ltered aliquot for testing.
It should be noted that GEL did not adjust sample pH prior to the October 2 (8th pull) sampling. This oversight was identi"ed during project reviews, where lower-than-expected Kd values were observed compared to the literature. Fortunately, pH adjustments were resumed in time to stabilize Kd results for the study and values were calculated using the ASTM equation shown below.
Equation 1: ASTM method calculation
1
Where:
V is the volume of ground water Cs is the reference value for the isotope of interest Cf is the observed value in the sample during the study intervals M is the dry weight mass of sample used in the study F is the mass of material removed from the sample >2mm le] =I* I Laboratories LLc a member of The GEL Group INC 2040 Savage Road I Charleston, SC 29407 843.556.8171 gel.com
Distribution Coefficient (Kd) Method Report November 22, 2024 Page 3 of 22 Quality Assurance Reference solutions were made using the 2 ground water sample types as shown in Table 2. As anticipated, the addition of acid-preserved standards lowered the pH of the groundwater samples, which was then adjusted back to the original pH using 6M NaOH.
Table 2: Standards used for Kd study Isotope and source ID Spike Volume 450 mL Spike Volume 100 mL Approximate Activity (pCi/mL)
Average Recovery Americium-241 2058-A 5.0 1.0 560 63%
Cesium-137 2153-A 3.0 1.0 650 106%
Cobalt-60 2154-A 3.0 1.0 700 95%
Strontium-85 2157-A 5.0 1.0 700 86%
Technetium-99 2113-A 5.0 1.0 700 101%
Iron-55 2155-A 3.0 1.0 60 51%
Carbon-14 2152-A 3.0 1.0 650 71%
The reference standards were compared with estimated spiked values and tracked over the course of the study. The iron activity was 10x lower than expected and this anomaly was tracked to an error in the activity value provided by the standard manufacturer. GEL determined that the iron activity was su icient and proceeded with the study.
Isotope recoveries were comparable with the estimated spiked values with the exceptions of americium and iron (see Table 2 Average Recovery. Americium and other transuranic elements stored without preservation can be absorbed into container walls over time and this is a potential cause of the 63% average recovery. Samples and associated references used the same type of containers during the study, so it appears the impact of absorption was comparable between the reference and samples as shown in the Kd values determined.
Iron was also low compared to the spiked value at an average of 51% (see Table 2 Average Recovery). This low recovery could have been caused by precipitation of iron in the ground water which was "ltered during each sample collection. Since samples and references had similar "ltration processes, the impact of the low iron yields was replicated between sample and reference and should not negatively impact Kd values.
le] =I* I Laboratories LLc a member of The GEL Group INC 2040 Savage Road I Charleston, SC 29407 843.556.8171 gel.com
Distribution Coefficient (Kd) Method Report November 22, 2024 Page 4 of 22 Summary Tables and Conclusions The method showed strong performance for selected isotopes, aligning well with literature values once pH was adjusted to match the original groundwater conditions. While the oversight of not consistently monitoring pH will be addressed in future studies, the notable impact on speci"c isotopes when the solid matrices reduced the pH during the study provided valuable insights.
Summary tables for the samples and selected isotopes are provided below and any questions regarding this study can be directed to Mr. James Westmoreland, Director Radiochemistry james.westmoreland@gel.com.
Kd Summary Tables - Americium 241 Date NOCA Fill pH Reference Result Am Kd 8/12/2024 sample 1 509 72 149 8/16/2024 sample 2 340 60 114 8/21/2024 sample 3 363 65 112 8/28/2024 sample 4 377 84 85 9/4/2024 sample 5 365 154 34 9/11/2024 sample 6 358 175 26 9/18/2024 sample 7 2.53 363 208 18 10/2/2024 sample 8 2.41 326 255 7
10/9/2024 sample 9 2.53 323 316 1
10/16/2024 sample 10 7.7 314 1(a) 10400 10/23/2024 sample 11 7.7 316 1
9990 10/30/2024 sample 12 7.78 338 2(a) 5430 11/4/2024 Final 7.72 295 1
7860 Average value (sample 12 and Final) 6650 (a) MDC value reported le] =I* I Laboratories LLc a member of The GEL Group INC 2040 Savage Road I Charleston, SC 29407 843.556.8171 gel.com
Distribution Coefficient (Kd) Method Report November 22, 2024 Page 5 of 22 Kd summary Tables - Americium 241 continued Date Fill Sand pH Reference Result Am Kd 8/12/2024 sample 1 509 36 321 8/16/2024 sample 2 340 12 658 8/21/2024 sample 3 363 11 797 8/28/2024 sample 4 377 11 826 9/4/2024 sample 5 365 9
975 9/11/2024 sample 6 358 7
1280 9/18/2024 sample 7 6.06 363 7
1310 10/2/2024 sample 8 6.43 326 6
1370 10/9/2024 sample 9 7.24 323 10 750 10/16/2024 sample 10 7.7 314 8
999 10/23/2024 sample 11 7.77 316 6
1200 10/30/2024 sample 12 7.78 338 7
1090 11/4/2024 Final 7.77 295 5
1430 Average value (sample 12 and Final) 1260 Date Cape May Sand pH Reference Result Am Kd 8/12/2024 sample 1 509 2
5640 8/16/2024 sample 2 340 2
3430 8/21/2024 sample 3 363 2
4310 8/28/2024 sample 4 377 3
3130 9/4/2024 sample 5 365 3
3090 9/11/2024 sample 6 358 4
2210 9/18/2024 sample 7 5.56 363 2
3530 10/2/2024 sample 8 5.52 326 1(a) 7830 10/9/2024 sample 9 6.92 323 1
6090 10/16/2024 sample 10 7.69 314 4
1870 10/23/2024 sample 11 7.65 316 2
4860 10/30/2024 sample 12 7.73 338 2(a) 5250 11/4/2024 Final 7.79 295 1
5010 Average value (sample 12 and Final) 5130 (a) MDC value reported le] =I* I Laboratories LLc a member of The GEL Group INC 2040 Savage Road I Charleston, SC 29407 843.556.8171 gel.com
Distribution Coefficient (Kd) Method Report November 22, 2024 Page 6 of 22 Kd Summary Tables - Americium 241 continued Date Cape May lower clay pH Reference Result Am Kd 8/12/2024 sample 1 509 18 651 8/16/2024 sample 2 340 29 261 8/21/2024 sample 3 363 53 142 8/28/2024 sample 4 377 84 86 9/4/2024 sample 5 365 111 56 9/11/2024 sample 6 358 172 26 9/18/2024 sample 7 2.87 363 196 21 10/2/2024 sample 8 2.62 326 263 6
10/9/2024 sample 9 2.72 323 308 1
10/16/2024 sample 10 7.66 314 1(a) 7710 10/23/2024 sample 11 7.7 316 1
9920 10/30/2024 sample 12 7.78 338 2
4740 11/4/2024 Final 7.72 295 2
4650 Average value (sample 12 and Final) 4690 (a) MDC value reported Date Cohansey sand pH Reference Result Am Kd 8/12/2024 sample 1 445 8
1360 8/16/2024 sample 2 154 6
626 8/21/2024 sample 3 143 5
673 8/28/2024 sample 4 123 5
643 9/4/2024 sample 5 285 5
1430 9/11/2024 sample 6 278 3
1970 9/18/2024 sample 7 6.48 260 4
1700 10/2/2024 sample 8 6.84 250 4
1550 10/9/2024 sample 9 6.77 236 5
1030 10/16/2024 sample 10 7.04 246 22 252 10/23/2024 sample 11 7.07 235 5
1160 10/30/2024 sample 12 7.01 219 10 512 11/4/2024 Final 7.06 95 2
937 Average value (sample 12 and Final) 724 le] =I* I Laboratories LLc a member of The GEL Group INC 2040 Savage Road I Charleston, SC 29407 843.556.8171 gel.com
Distribution Coefficient (Kd) Method Report November 22, 2024 Page 7 of 22 Kd Summary Tables - Americium 241 continued Date Lower Clay pH Reference Result Am Kd 8/12/2024 sample 1 445 42 235 8/16/2024 sample 2 154 46 58 8/21/2024 sample 3 143 81 19 8/28/2024 sample 4 123 107 4
9/4/2024 sample 5 285 139 26 9/11/2024 sample 6 278 183 13 9/18/2024 sample 7 2.63 260 212 6
10/2/2024 sample 8 2.51 250 244 1
10/9/2024 sample 9 2.54 236 287 0
10/16/2024 sample 10 7.15 246 1
7840 10/23/2024 sample 11 7.05 235 1(a) 9650 10/30/2024 sample 12 7.01 219 1(a) 5730 11/4/2024 Final 7.09 95 1(a) 5580 Average value (sample 12 and Final) 5650 (a) MDC value reported Kd Summary Tables - Cesium 137 Date NOCA Fill pH Reference Result Cs kd 8/12/2024 sample 1 653 28 555 8/16/2024 sample 2 647 16 960 8/21/2024 sample 3 679 11 1550 8/28/2024 sample 4 671 8
1950 9/4/2024 sample 5 674 10 1600 9/11/2024 sample 6 667 8
2020 9/18/2024 sample 7 2.53 688 11 1500 10/2/2024 sample 8 2.41 654 9
1740 10/9/2024 sample 9 2.53 669 12 1400 10/16/2024 sample 10 7.7 643 3
4740 10/23/2024 sample 11 7.7 657 5
3380 10/30/2024 sample 12 7.78 672 5
3350 11/4/2024 Final 7.72 952 8
3010 Average value (sample 12 and Final) 3180 le] =I* I Laboratories LLc a member of The GEL Group INC 2040 Savage Road I Charleston, SC 29407 843.556.8171 gel.com
Distribution Coefficient (Kd) Method Report November 22, 2024 Page 8 of 22 Kd Summary Tables - Cesium 137 continued Date Fill Sand pH Reference Result Cs kd 8/12/2024 sample 1 653 21 753 8/16/2024 sample 2 647 18 870 8/21/2024 sample 3 679 12 1380 8/28/2024 sample 4 671 13 1290 9/4/2024 sample 5 674 12 1410 9/11/2024 sample 6 667 9
1740 9/18/2024 sample 7 6.06 688 11 1510 10/2/2024 sample 8 6.43 654 14 1130 10/9/2024 sample 9 7.24 669 20 816 10/16/2024 sample 10 7.7 643 11 1390 10/23/2024 sample 11 7.77 657 13 1260 10/30/2024 sample 12 7.78 672 13 1200 11/4/2024 Final 7.77 952 29 794 Average value (sample 12 and Final) 996 Date Cape May Sand pH Reference Result Cs kd 8/12/2024 sample 1 653 43 346 8/16/2024 sample 2 647 31 484 8/21/2024 sample 3 679 28 578 8/28/2024 sample 4 671 25 636 9/4/2024 sample 5 674 23 684 9/11/2024 sample 6 667 23 686 9/18/2024 sample 7 5.56 688 21 762 10/2/2024 sample 8 5.52 654 18 845 10/9/2024 sample 9 6.92 669 14 1170 10/16/2024 sample 10 7.69 643 16 944 10/23/2024 sample 11 7.65 657 14 1150 10/30/2024 sample 12 7.73 672 15 1070 11/4/2024 Final 7.79 952 19 1200 Average value (sample 12 and Final) 1140 le] =I* I Laboratories LLc a member of The GEL Group INC 2040 Savage Road I Charleston, SC 29407 843.556.8171 gel.com
Distribution Coefficient (Kd) Method Report November 22, 2024 Page 9 of 22 Kd Summary Tables - Cesium 137 continued Date Cape May Lower Clay pH Reference Result Cs kd 8/12/2024 sample 1 653 17 943 8/16/2024 sample 2 647 12 1330 8/21/2024 sample 3 679 11 1490 8/28/2024 sample 4 671 10 1560 9/4/2024 sample 5 674 13 1240 9/11/2024 sample 6 667 10 1670 9/18/2024 sample 7 2.87 688 8
2010 10/2/2024 sample 8 2.62 654 10 1570 10/9/2024 sample 9 2.72 669 11 1430 10/16/2024 sample 10 7.66 643 5
2910 10/23/2024 sample 11 7.7 657 4
4010 10/30/2024 sample 12 7.78 672 4
3870 11/4/2024 Final 7.72 952 8
3110 Average value (sample 12 and Final) 3490 Date Cohansey Sand pH Reference Result Cs kd 8/12/2024 sample 1 619 573 2
8/16/2024 sample 2 680 557 5
8/21/2024 sample 3 645 554 4
8/28/2024 sample 4 626 564 3
9/4/2024 sample 5 688 551 6
9/11/2024 sample 6 649 553 4
9/18/2024 sample 7 6.48 618 518 5
10/2/2024 sample 8 6.84 654 500 8
10/9/2024 sample 9 6.77 634 542 4
10/16/2024 sample 10 7.04 627 519 5
10/23/2024 sample 11 7.07 631 521 5
10/30/2024 sample 12 7.01 646 493 8
11/4/2024 Final 7.06 960 749 7
Average value (sample 12 and Final) 7 le] =I* I Laboratories LLc a member of The GEL Group INC 2040 Savage Road I Charleston, SC 29407 843.556.8171 gel.com
Distribution Coefficient (Kd) Method Report November 22, 2024 Page 10 of 22 Kd Summary Tables - Cesium 137 continued Date Lower Clay pH Reference Result Cs kd 8/12/2024 sample 1 619 17 865 8/16/2024 sample 2 680 12 1310 8/21/2024 sample 3 645 11 1480 8/28/2024 sample 4 626 9
1680 9/4/2024 sample 5 688 12 1390 9/11/2024 sample 6 649 6
2470 9/18/2024 sample 7 2.63 618 8
1980 10/2/2024 sample 8 2.51 654 7
2120 10/9/2024 sample 9 2.54 634 6
2570 10/16/2024 sample 10 7.15 627 2
7500 10/23/2024 sample 11 7.05 631 2
7350 10/30/2024 sample 12 7.01 646 4
4450 11/4/2024 Final 7.09 960 5
5230 Average value (sample 12 and Final) 4840 Kd Summary Tables - Cobalt 60 Date NOCA Fill pH Reference Result Co kd 8/12/2024 sample 1 688 544 6
8/16/2024 sample 2 595 570 1
8/21/2024 sample 3 654 621 1
8/28/2024 sample 4 629 592 2
9/4/2024 sample 5 668 634 1
9/11/2024 sample 6 662 614 2
9/18/2024 sample 7 2.53 665 605 2
10/2/2024 sample 8 2.41 632 629 0
10/9/2024 sample 9 2.53 653 681 0
10/16/2024 sample 10 7.7 635 14 1090 10/23/2024 sample 11 7.7 632 3
6160 10/30/2024 sample 12 7.78 638 2
8370 11/4/2024 Final 7.72 881 4
5550 Average value (sample 12 and Final) 6960 le] =I* I Laboratories LLc a member of The GEL Group INC 2040 Savage Road I Charleston, SC 29407 843.556.8171 gel.com
Distribution Coefficient (Kd) Method Report November 22, 2024 Page 11 of 22 Kd Summary Tables - Cobalt 60 continued Date Fill Sand pH Reference Result Co kd 8/12/2024 sample 1 688 29 566 8/16/2024 sample 2 595 24 587 8/21/2024 sample 3 654 13 1210 8/28/2024 sample 4 629 12 1210 9/4/2024 sample 5 668 11 1500 9/11/2024 sample 6 662 8
2060 9/18/2024 sample 7 6.06 665 9
1720 10/2/2024 sample 8 6.43 632 8
2030 10/9/2024 sample 9 7.24 653 11 1380 10/16/2024 sample 10 7.7 635 7
2170 10/23/2024 sample 11 7.77 632 4
3570 10/30/2024 sample 12 7.78 638 8
1910 11/4/2024 Final 7.77 881 7
3270 Average value (sample 12 and Final) 2590 Date Cape May Sand pH Reference Result Co kd 8/12/2024 sample 1 688 22 749 8/16/2024 sample 2 595 9
1540 8/21/2024 sample 3 654 8
1920 8/28/2024 sample 4 629 7
2160 9/4/2024 sample 5 668 7
2440 9/11/2024 sample 6 662 7
2460 9/18/2024 sample 7 5.56 665 6
2720 10/2/2024 sample 8 5.52 632 3
6000 10/9/2024 sample 9 6.92 653 2
6590 10/16/2024 sample 10 7.69 635 7
2070 10/23/2024 sample 11 7.65 632 3
5590 10/30/2024 sample 12 7.73 638 3
4920 11/4/2024 Final 7.79 881 3
8300 Average value (sample 12 and Final) 6610 le] =I* I Laboratories LLc a member of The GEL Group INC 2040 Savage Road I Charleston, SC 29407 843.556.8171 gel.com
Distribution Coefficient (Kd) Method Report November 22, 2024 Page 12 of 22 Kd Summary Tables - Cobalt 60 continued Date Cape May Lower Clay pH Reference Result Co kd 8/12/2024 sample 1 688 484 10 8/16/2024 sample 2 595 527 3
8/21/2024 sample 3 654 561 4
8/28/2024 sample 4 629 625 0
9/4/2024 sample 5 668 649 1
9/11/2024 sample 6 662 648 1
9/18/2024 sample 7 2.87 665 609 2
10/2/2024 sample 8 2.62 632 678 0
10/9/2024 sample 9 2.72 653 658 0
10/16/2024 sample 10 7.66 635 4
3730 10/23/2024 sample 11 7.7 632 3
5030 10/30/2024 sample 12 7.78 638 3
5060 11/4/2024 Final 7.72 881 4
5070 Average value (sample 12 and Final) 5070 Date Cohansey sand pH Reference Result Co kd 8/12/2024 sample 1 681 572 5
8/16/2024 sample 2 689 587 4
8/21/2024 sample 3 660 593 3
8/28/2024 sample 4 656 585 3
9/4/2024 sample 5 725 575 6
9/11/2024 sample 6 688 543 7
9/18/2024 sample 7 6.48 681 525 7
10/2/2024 sample 8 6.84 700 479 11 10/9/2024 sample 9 6.77 699 442 14 10/16/2024 sample 10 7.04 658 344 22 10/23/2024 sample 11 7.07 674 339 24 10/30/2024 sample 12 7.01 692 284 35 11/4/2024 Final 7.06 1000 173 120 Average value (sample 12 and Final) 77 le] =I* I Laboratories LLc a member of The GEL Group INC 2040 Savage Road I Charleston, SC 29407 843.556.8171 gel.com
Distribution Coefficient (Kd) Method Report November 22, 2024 Page 13 of 22 Kd Summary Tables - Cobalt 60 continued Date Lower Clay pH Reference Result Co kd 8/12/2024 sample 1 681 557 5
8/16/2024 sample 2 689 557 6
8/21/2024 sample 3 660 614 2
8/28/2024 sample 4 656 610 2
9/4/2024 sample 5 725 595 5
9/11/2024 sample 6 688 640 2
9/18/2024 sample 7 2.63 681 662 1
10/2/2024 sample 8 2.51 700 622 3
10/9/2024 sample 9 2.54 699 648 2
10/16/2024 sample 10 7.15 658 21 735 10/23/2024 sample 11 7.05 674 4
3750 10/30/2024 sample 12 7.05 692 6
2620 11/4/2024 Final 7.09 1000 4
7070 Average value (sample 12 and Final) 4850 Kd Summary Tables - Strontium 90 Date NOCA Fill pH Reference Result Sr kd 8/12/2024 sample 1 657 518 7
8/16/2024 sample 2 626 516 5
8/21/2024 sample 3 687 575 5
8/28/2024 sample 4 675 547 6
9/4/2024 sample 5 668 604 3
9/11/2024 sample 6 655 567 4
9/18/2024 sample 7 2.53 674 579 4
10/2/2024 sample 8 2.41 631 579 2
10/9/2024 sample 9 2.53 625 633 0
10/16/2024 sample 10 7.7 583 70 178 10/23/2024 sample 11 7.7 593 33 414 10/30/2024 sample 12 7.78 657 30 517 11/4/2024 Final 7.72 212 13 381 Average value (sample 12 and Final) 449 le] =I* I Laboratories LLc a member of The GEL Group INC 2040 Savage Road I Charleston, SC 29407 843.556.8171 gel.com
Distribution Coefficient (Kd) Method Report November 22, 2024 Page 14 of 22 Kd Summary Tables - Strontium 90 continued Date Fill Sand pH Reference Result Sr kd 8/12/2024 sample 1 657 346 22 8/16/2024 sample 2 626 353 19 8/21/2024 sample 3 687 324 27 8/28/2024 sample 4 675 346 23 9/4/2024 sample 5 668 332 25 9/11/2024 sample 6 655 281 33 9/18/2024 sample 7 6.06 674 322 27 10/2/2024 sample 8 6.43 631 297 28 10/9/2024 sample 9 7.24 625 267 33 10/16/2024 sample 10 7.7 583 254 32 10/23/2024 sample 11 7.77 593 257 32 10/30/2024 sample 12 7.78 657 270 35 11/4/2024 Final 7.77 212 107 25 Average value (sample 12 and Final) 30 Date Cape May Sand pH Reference Result Sr kd 8/12/2024 sample 1 657 490 8
8/16/2024 sample 2 626 524 5
8/21/2024 sample 3 687 522 8
8/28/2024 sample 4 675 517 7
9/4/2024 sample 5 668 488 9
9/11/2024 sample 6 655 523 6
9/18/2024 sample 7 5.56 674 496 9
10/2/2024 sample 8 5.52 631 414 13 10/9/2024 sample 9 6.92 625 341 20 10/16/2024 sample 10 7.69 583 304 22 10/23/2024 sample 11 7.65 593 255 32 10/30/2024 sample 12 7.73 657 231 45 11/4/2024 Final 7.79 212 85 38 Average value (sample 12 and Final) 41 le] =I* I Laboratories LLc a member of The GEL Group INC 2040 Savage Road I Charleston, SC 29407 843.556.8171 gel.com
Distribution Coefficient (Kd) Method Report November 22, 2024 Page 15 of 22 Kd Summary Tables - Strontium 90 continued Date Cape May Lower Clay pH Reference Result Sr kd 8/12/2024 sample 1 657 501 8
8/16/2024 sample 2 626 516 5
8/21/2024 sample 3 687 542 7
8/28/2024 sample 4 675 600 3
9/4/2024 sample 5 668 619 2
9/11/2024 sample 6 655 607 2
9/18/2024 sample 7 2.87 674 585 4
10/2/2024 sample 8 2.62 631 587 2
10/9/2024 sample 9 2.72 625 609 1
10/16/2024 sample 10 7.66 583 45 296 10/23/2024 sample 11 7.7 593 40 340 10/30/2024 sample 12 7.78 657 35 435 11/4/2024 Final 7.72 212 14 344 Average value (sample 12 and Final) 390 Date Cohansey Sand pH Reference Result Sr kd 8/12/2024 sample 1 642 644 0
8/16/2024 sample 2 653 633 1
8/21/2024 sample 3 634 650 0
8/28/2024 sample 4 625 650 0
9/4/2024 sample 5 666 650 1
9/11/2024 sample 6 627 651 0
9/18/2024 sample 7 6.48 619 613 0
10/2/2024 sample 8 6.84 617 624 0
10/9/2024 sample 9 6.77 587 644 0
10/16/2024 sample 10 7.04 608 606 0
10/23/2024 sample 11 7.07 613 576 2
10/30/2024 sample 12 7.01 639 606 1
11/4/2024 Final 7.06 222 200 3
Average value (sample 12 and Final) 2 le] =I* I Laboratories LLc a member of The GEL Group INC 2040 Savage Road I Charleston, SC 29407 843.556.8171 gel.com
Distribution Coefficient (Kd) Method Report November 22, 2024 Page 16 of 22 Kd Summary Tables - Strontium 90 continued Date Lower Clay pH Reference Result Sr kd 8/12/2024 sample 1 642 507 7
8/16/2024 sample 2 653 515 7
8/21/2024 sample 3 634 574 3
8/28/2024 sample 4 625 572 2
9/4/2024 sample 5 666 558 5
9/11/2024 sample 6 627 601 1
9/18/2024 sample 7 2.63 619 614 0
10/2/2024 sample 8 2.51 631 570 3
10/9/2024 sample 9 2.54 625 582 2
10/16/2024 sample 10 7.15 608 72 181 10/23/2024 sample 11 7.05 613 42 329 10/30/2024 sample 12 7.01 639 47 311 11/4/2024 Final 7.09 222 9
584 Average value (sample 12 and Final) 448 Kd Summary Tables - Technetium 99 Date NOCA Fill pH Reference Result Tc kd 8/12/2024 sample 1 792 740 2
8/16/2024 sample 2 239 221 2
8/21/2024 sample 3 744 629 4
8/28/2024 sample 4 757 592 7
9/4/2024 sample 5 758 573 8
9/11/2024 sample 6 730 539 9
9/18/2024 sample 7 3.22 751 498 12 10/2/2024 sample 8 3.01 751 440 17 10/9/2024 sample 9 3.01 753 407 21 10/16/2024 sample 10 7.86 747 82 199 10/23/2024 sample 11 7.79 734 747 0
10/30/2024 sample 12 7.75 756 251 49 11/4/2024 Final 7.8 669 236 46 Average value (sample 12 and Final) 48 le] =I* I Laboratories LLc a member of The GEL Group INC 2040 Savage Road I Charleston, SC 29407 843.556.8171 gel.com
Distribution Coefficient (Kd) Method Report November 22, 2024 Page 17 of 22 Kd Summary Tables - Technetium 99 continued Date Fill Sand pH Reference Result Tc kd 8/12/2024 sample 1 792 792 0
8/16/2024 sample 2 239 248 0
8/21/2024 sample 3 744 748 0
8/28/2024 sample 4 757 731 1
9/4/2024 sample 5 758 759 0
9/11/2024 sample 6 730 737 0
9/18/2024 sample 7 7.49 751 738 0
10/2/2024 sample 8 7.75 751 745 0
10/9/2024 sample 9 7.18 753 735 1
10/16/2024 sample 10 7.73 747 734 0
10/23/2024 sample 11 7.78 734 753 0
10/30/2024 sample 12 7.74 756 744 0
11/4/2024 Final 7.68 669 676 0
Average value (sample 12 and Final) 0 Date Cape May Sand pH Reference Result Tc kd 8/12/2024 sample 1 792 798 0
8/16/2024 sample 2 239 251 0
8/21/2024 sample 3 744 739 0
8/28/2024 sample 4 757 731 1
9/4/2024 sample 5 758 742 1
9/11/2024 sample 6 730 745 0
9/18/2024 sample 7 7.33 751 738 0
10/2/2024 sample 8 7.78 751 756 0
10/9/2024 sample 9 7.29 753 737 1
10/16/2024 sample 10 7.72 747 753 0
10/23/2024 sample 11 7.73 734 740 0
10/30/2024 sample 12 7.79 756 737 1
11/4/2024 Final 7.77 669 666 0
Average value (sample 12 and Final) 0 le] =I* I Laboratories LLc a member of The GEL Group INC 2040 Savage Road I Charleston, SC 29407 843.556.8171 gel.com
Distribution Coefficient (Kd) Method Report November 22, 2024 Page 18 of 22 Kd Summary Tables - Technetium 99 continued Date Cape May lower clay pH Reference Result Tc kd 8/12/2024 sample 1 792 793 0
8/16/2024 sample 2 239 239 0
8/21/2024 sample 3 744 685 2
8/28/2024 sample 4 757 646 4
9/4/2024 sample 5 758 599 6
9/11/2024 sample 6 730 585 6
9/18/2024 sample 7 2.77 751 571 8
10/2/2024 sample 8 2.58 751 534 10 10/9/2024 sample 9 2.65 753 513 11 10/16/2024 sample 10 7.84 747 396 22 10/23/2024 sample 11 7.81 734 496 12 10/30/2024 sample 12 7.77 756 521 11 11/4/2024 Final 7.7 669 656 1
Average value (sample 12 and Final) 6 Date Cohansey Sand pH Reference Result Tc kd 8/12/2024 sample 1 805 800 0
8/16/2024 sample 2 256 252 0
8/21/2024 sample 3 758 760 0
8/28/2024 sample 4 746 737 0
9/4/2024 sample 5 759 741 1
9/11/2024 sample 6 755 746 0
9/18/2024 sample 7 7.04 751 739 0
10/2/2024 sample 8 7.13 752 729 1
10/9/2024 sample 9 7.06 746 753 0
10/16/2024 sample 10 7.04 747 746 0
10/23/2024 sample 11 7.02 739 729 0
10/30/2024 sample 12 7.13 737 746 0
11/4/2024 Final 7.05 669 656 0
Average value (sample 12 and Final) 0 le] =I* I Laboratories LLc a member of The GEL Group INC 2040 Savage Road I Charleston, SC 29407 843.556.8171 gel.com
Distribution Coefficient (Kd) Method Report November 22, 2024 Page 19 of 22 Kd Summary Tables - Technetium 99 continued Date Lower Clay pH Reference Result Tc kd 8/12/2024 sample 1 805 704 4
8/16/2024 sample 2 256 212 5
8/21/2024 sample 3 758 591 7
8/28/2024 sample 4 746 512 11 9/4/2024 sample 5 759 438 18 9/11/2024 sample 6 755 371 25 9/18/2024 sample 7 2.63 751 312 34 10/2/2024 sample 8 2.44 752 189 73 10/9/2024 sample 9 2.54 746 181 76 10/16/2024 sample 10 7.15 747 181 76 10/23/2024 sample 11 7.11 739 266 44 10/30/2024 sample 12 7.09 737 309 34 11/4/2024 Final 7.07 669 169 74 Average value (sample 12 and Final) 54 Kd Summary Tables - Iron 55 Date NOCA Fill pH Reference Result Fe kd 8/12/2024 sample 1 39 11 67 8/16/2024 sample 2 31 11 46 8/21/2024 sample 3 30 13 32 8/28/2024 sample 4 31 16 22 9/4/2024 sample 5 31 20 13 9/11/2024 sample 6 28 20 10 9/18/2024 sample 7 2.83 34 30 4
10/2/2024 sample 8 2.63 29 34 0
10/9/2024 sample 9 2.66 29 36 0
10/16/2024 sample 10 7.81 29 1(a) 1170 10/23/2024 sample 11 7.78 26 1(a) 1060 10/30/2024 sample 12 7.77 24 1(a) 911 11/4/2024 Final 7.82 40 1(a) 1770 Average value (sample 12 and Final) 1340 (a) MDC value reported le] =I* I Laboratories LLc a member of The GEL Group INC 2040 Savage Road I Charleston, SC 29407 843.556.8171 gel.com
Distribution Coefficient (Kd) Method Report November 22, 2024 Page 20 of 22 Summary Tables - Iron 55 continued Date Fill Sand pH Reference Result Fe kd 8/12/2024 sample 1 39 4
246 8/16/2024 sample 2 31 1
781 8/21/2024 sample 3 30 1
865 8/28/2024 sample 4 31 2
475 9/4/2024 sample 5 31 1
568 9/11/2024 sample 6 28 1
728 9/18/2024 sample 7 7.33 34 1
617 10/2/2024 sample 8 7.08 29 2
262 10/9/2024 sample 9 7.22 29 1
444 10/16/2024 sample 10 7.78 29 2
333 10/23/2024 sample 11 7.71 26 2
298 10/30/2024 sample 12 7.72 24 2
372 11/4/2024 Final 7.72 40 1
904 Average value (sample 12 and Final) 638 Date Cape May Sand pH Reference Result Fe kd 8/12/2024 sample 1 39 1
1210 8/16/2024 sample 2 31 1
600 8/21/2024 sample 3 30 1
909 8/28/2024 sample 4 31 1
608 9/4/2024 sample 5 31 1
735 9/11/2024 sample 6 28 1
740 9/18/2024 sample 7 7.35 34 1
1400 10/2/2024 sample 8 7.04 29 2
360 10/9/2024 sample 9 7.07 29 1
521 10/16/2024 sample 10 7.76 29 2
347 10/23/2024 sample 11 7.72 26 2
298 10/30/2024 sample 12 7.72 24 2
326 11/4/2024 Final 7.79 40 1(a) 1880 Average value (sample 12 and Final) 1100 (a) MDC value reported le] =I* I Laboratories LLc a member of The GEL Group INC 2040 Savage Road I Charleston, SC 29407 843.556.8171 gel.com
Distribution Coefficient (Kd) Method Report November 22, 2024 Page 21 of 22 Summary Tables - Iron 55 continued Date Cape May Lower Clay pH Reference Result Fe kd 8/12/2024 sample 1 39 2
426 8/16/2024 sample 2 31 1
1010 8/21/2024 sample 3 30 1
915 8/28/2024 sample 4 31 1
809 9/4/2024 sample 5 31 4
186 9/11/2024 sample 6 28 5
107 9/18/2024 sample 7 2.88 34 10 63 10/2/2024 sample 8 2.6 29 19 13 10/9/2024 sample 9 2.64 29 21 9
10/16/2024 sample 10 7.82 29 1(a) 1140 10/23/2024 sample 11 7.78 26 1(a) 991 10/30/2024 sample 12 7.76 24 1(a) 970 11/4/2024 Final 7.79 40 1(a) 1890 Average value (sample 12 and Final) 1430 (a) MDC value reported Date Cohansey Sand pH Reference Result Fe kd 8/12/2024 sample 1 10 3
55 8/16/2024 sample 2 4
0.3 253 8/21/2024 sample 3 3
1 131 8/28/2024 sample 4 17 1
567 9/4/2024 sample 5 16 1
612 9/11/2024 sample 6 13 0.4 736 9/18/2024 sample 7 6.89 16 0.4 962 10/2/2024 sample 8 7.06 10 1
194 10/9/2024 sample 9 6.89 9
1 127 10/16/2024 sample 10 7.11 7
1 138 10/23/2024 sample 11 7.01 6
1 112 10/30/2024 sample 12 7.12 4
1 89 11/4/2024 Final 7.79 2
1 52 Average value (sample 12 and Final) 71 le] =I* I Laboratories LLc a member of The GEL Group INC 2040 Savage Road I Charleston, SC 29407 843.556.8171 gel.com
Distribution Coefficient (Kd) Method Report November 22, 2024 Page 22 of 22 Summary Tables - Iron 55 continued Date Lower Clay pH Reference Result Fe kd 8/12/2024 sample 1 10 24 0
8/16/2024 sample 2 4
16 0
8/21/2024 sample 3 3
15 0
8/28/2024 sample 4 17 8
31 9/4/2024 sample 5 16 8
26 9/11/2024 sample 6 13 8
15 9/18/2024 sample 7 2.67 16 12 9
10/2/2024 sample 8 2.51 10 19 0
10/9/2024 sample 9 2.59 9
21 0
10/16/2024 sample 10 7.01 7
1(a) 285 10/23/2024 sample 11 7.12 6
1(a) 227 10/30/2024 sample 12 7.09 4
1(a) 164 11/4/2024 Final 7.78 2
1(a) 72 Average value (sample 12 and Final) 118 (a) MDC value reported Summary Table - Carbon 14 Date NOCA Fill pH Reference Result C kd 8/12/2024 sample 1 311 10 734 8/16/2024 sample 2 510 152 58 8/21/2024 sample 3 544 91 121 8/28/2024 sample 4 525 47 247 9/4/2024 sample 5 522 21 577 9/11/2024 sample 6 503 12 982 9/18/2024 sample 7 3.04 496 9
1350 10/2/2024 sample 8 2.69 452 2
6980 10/9/2024 sample 9 2.81 447 2
7000 10/16/2024 sample 10 7.79 445 2
5600 10/23/2024 sample 11 7.77 424 1
10500 10/30/2024 sample 12 7.71 393 1
12300 11/4/2024 Final 7.84 722 5
3940 Average value (sample 12 and Final) 8100 le] =I* I Laboratories LLc a member of The GEL Group INC 2040 Savage Road I Charleston, SC 29407 843.556.8171 gel.com