ML20284A204

Fuel Fabrication Facility, Hopkins, Richland County, South Carolina - 2019/2020 Annual Groundwater Monitoring Report

ML20284A204
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Site:	Westinghouse
Issue date:	09/28/2020
From:	Suddeth C AECOM Technical Services, Westinghouse
To:	Office of Nuclear Material Safety and Safeguards
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ML20284A202	List: ML20284A203 ML20284A204
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Westinghouse Electric Company, LLC 5801 Bluff Road Hopkins, SC 29061 2019/2020 Annual Groundwater Monitoring Report Columbia Fuel Fabrication Facility Hopkins, Richland County, South Carolina Westinghouse Electric Company, LLC.

Project number: 60595649 September 28, 2020

2019/2020 Annual Groundwater Monitoring Report Project number: 60595649 Prepared for: Westinghouse Electric Company, LLC AECOM Quality information Prepared by Checked by Chuck Suddeth Project Manager charles.suddeth@aecom.com 803-254-4400 Jeremy Grant Remediation Services Lead jeremy.grant@aecom.com 803-400-0090 Prepared for:

Westinghouse Electric Company, LLC 5801 Bluff Road Hopkins, SC 29061 Prepared by:

Chuck Suddeth Jeremy Grant Project Manager Remediation Services Lead P: 803-400-0038 P: 803-400-0090 E: charles.suddeth@aecom.com jeremy.grant@aecom.com AECOM 101 Research Drive Columbia, SC 29203 aecom.com

2019/2020 Annual Groundwater Monitoring Report Project number: 60595649 i

Table of Contents

1.

Introduction............................................................................................................................................................ 1 1.1 Site Location and Physical Setting.......................................................................................................... 2 1.2 Site Operational Background................................................................................................................... 3 1.3 Facility Operational Units......................................................................................................................... 3 1.4 Geology and Hydrogeology..................................................................................................................... 3

2.

Groundwater Monitoring........................................................................................................................................ 5

3.

Results.................................................................................................................................................................. 6 3.1 Groundwater Flow................................................................................................................................... 6 3.1.1 Surficial Aquifer.................................................................................................................................. 6 3.1.2 Black Mingo Aquifer........................................................................................................................... 6 3.2 Groundwater Quality................................................................................................................................ 6 3.2.1 Chlorinated Volatile Organic Compounds (CVOCs)........................................................................... 6 3.2.1.1 PCE.......................................................................................................................................... 6 3.2.1.2 TCE........................................................................................................................................... 7 3.2.1.3 Cis-1,2-Dichloroethene............................................................................................................. 8 3.2.1.4 Vinyl Chloride............................................................................................................................ 8 3.2.2 SVOCs............................................................................................................................................... 8 3.2.3 Nitrate................................................................................................................................................ 8 3.2.4 Fluoride.............................................................................................................................................. 8 3.2.5 Uranium............................................................................................................................................. 9 3.2.6 Tc-99.................................................................................................................................................. 9 3.2.7 Other Monitoring Requirements....................................................................................................... 10 3.3 Non-Routine Groundwater Sampling..................................................................................................... 10

4.

Conclusions and Recommendations................................................................................................................... 10 4.1 Conclusions........................................................................................................................................... 10 4.2 Recommendations................................................................................................................................. 11

5.

References.......................................................................................................................................................... 11

2019/2020 Annual Groundwater Monitoring Report Project number: 60595649 ii Figures Figure 1 Site Location Map Figure 2 Property Map Figure 3 Site Map Figure 4 Operational Units Map Figure 5 Potentiometric Map - Surficial Aquifer - Upper Zone 10/19 Figure 6 Potentiometric Map - Surficial Aquifer - Upper Zone 4/20 Figure 7 Potentiometric Map - Black Mingo Aquifer 10/19 Figure 8 Potentiometric Map - Black Mingo Aquifer 4/20 Figure 9 Extent of PCE - Surficial Aquifer - Upper Zone 10/19 Figure 10 Extent of PCE - Surficial Aquifer - Upper Zone 4/20 Figure 11 Extent of PCE - Surficial Aquifer - Lower Zone 10/19 Figure 12 Extent of PCE - Surficial Aquifer - Lower Zone 4/20 Figure 13 Extent of TCE - Surficial Aquifer - Upper Zone 10/19 Figure 14 Extent of TCE - Surficial Aquifer - Upper Zone 4/20 Figure 15 Extent of TCE - Surficial Aquifer - Lower Zone 10/19 Figure 16 Extent of TCE - Surficial Aquifer - Lower Zone 4/20 Figure 17 Extent of Nitrate in Groundwater 10/19 Figure 18 Extent of Nitrate in Groundwater 4/20 Figure 19 Extent of Fluoride in Groundwater 10/19 Figure 20 Extent of Fluoride in Groundwater 4/20 Figure 21 Extent of Uranium in Groundwater 10/19 Figure 22 Extent of Uranium in Groundwater 4/20 Figure 23 Extent of Technetium-99 in Groundwater 10/19 Figure 24 Extent of Technetium-99 in Groundwater 4/20 Tables Table 1 Monitoring Well Construction Details Table 2 Groundwater Levels and Elevations Table 3 Summary of Groundwater Field Parameter Data Table 4 Summary of Groundwater Analytical Results Appendices Appendix A Groundwater Sample Collection Records Appendix B Laboratory Analytical Reports Appendix C Historical Groundwater Monitoring Data Appendix D Trend Plots Appendix E DHEC Correspondence

2019/2020 Annual Groundwater Monitoring Report Project number: 60595649 iii List of Acronyms AECOM AECOM Technical Services, Inc.

AOC Area of Concern BLS below land surface CA Consent Agreement CFFF Columbia Fuel Fabrication Facility cis-1,2 DCE cis-1,2-dichloroethene COPC constituent(s) of potential concern CVOC chlorinated volatile organic compound DHEC South Carolina Department of Health and Environmental Control EPA United States Environmental Protection Agency GEL Labs GEL Laboratories, LLC

µg/L micrograms per liter MCL maximum contaminant level mg/L milligram per liter MSL mean sea level NPDES National Pollution Discharge Elimination System NPL National Priority List OU Operational Unit Pace Pace Analytical Services, LLC PCE tetrachloroethylene pCi/L picocuries per liter RI remedial investigation Rust Rust Environment and Infrastructure S&ME Soil and Material Engineers SCRDI SCRDI Bluff Road Shealy Shealy Environmental Services, Inc.

SVOC Semi-Volatile Organic Compounds TAL Target Analyte List Tc-99 Technetium-99 TCE trichloroethylene TCL target compound list U

uranium VC vinyl chloride Westinghouse Westinghouse Electric Company, LLC WL2 West Lagoon 2 WWTP wastewater treatment plant

2019/2020 Annual Groundwater Monitoring Report Project number: 60595649 Prepared for: Westinghouse Electric Company, LLC AECOM 1

1.

Introduction Westinghouse Electric Company, LLC (Westinghouse) Columbia Fuel Fabrication Facility (CFFF) is located at 5801 Bluff Road (site or property) in Hopkins, approximately 15 miles southeast of Columbia, South Carolina (Figure 1).

The site includes approximately 1,151 acres, with the developed area encompassing approximately 75 acres centrally located on the site, thereby creating substantial buffers from adjoining properties. The property is surrounded by rural forested and agricultural property. CFFF was opened in 1969 and manufactures fuel assemblies and components for the commercial nuclear power industry. Site features are shown on Figure 2 and monitoring well locations are displayed on Figure 3.

On February 26, 2019, the South Carolina Department of Health and Environmental Control (DHEC) and CFFF entered into Consent Agreement (CA) 19-02-HW to comprehensively assess potential environmental impacts from current and historical operations, including additional assessment of known impacts. The CA requires further assessment and potential remediation of known constituents of potential concern (COPC) and assessment of additional areas where releases may have occurred. CFFF submitted a Final Remedial Investigation Work Plan to DHEC in June 2019 (AECOM, 2019a), which DHEC approved on June 19, 2019.

Assessment activities outlined in the June 2019 Final RI Work Plan (also referred to as Phase I) represented the first step in an iterative process to fulfill the requirements of the CA to assess the source, nature and extent of impacts from historical operations. The RI Phase I work was performed from June to December 2019.

As agreed with DHEC, an Interim Remedial Investigation Data Summary Report was prepared (AECOM, 2020a) to document the findings of the Phase I assessment activities. Based on comments from DHEC, CFFF submitted the Final Interim Remedial Investigation Data Summary Report on July 15, 2020 (AECOM, 2020b). On July 30, 2020, DHEC approved the report and requested a Phase II RI Work Plan be submitted by September 15, 2020.

In summary, the Phase I assessment data document the following:

Groundwater, surface water and sediment data indicate that there are no COPCs migrating off the site, and the documented impacts pose no potentially significant threat to plant workers, the general public or the environment.

A survey of water supply wells in the area identified the closest water supply well to be over 1 mile downgradient of the known areas impacted by COPCs. Analysis of groundwater samples from four private water supply wells, including the closest downgradient well, identified no COPCs related to CFFF manufacturing operations. These findings reinforce that there is no potential for COPCs from CFFF to impact private water supply wells.

A recently completed study (Leidos, 2020) has determined that current operations are not the source of Technetium-99 (Tc-99) in groundwater above the MCL.

In general, the vertical and horizontal extent of COPCs has been further defined and shows that the groundwater plume sizes and locations are similar to those previously identified.

Conditions within the floodplain are conducive to natural degradation and attenuation of the CVOC plume which will limit the plumes size.

Sediment impacted by COPCs is limited and well defined horizontally.

An improved understanding of site geology and hydrogeology has been developed, particularly with respect to the floodplain and how shallow groundwater interacts with surface water and sediment. The Conceptual Site Model (CSM) has been enhanced by the newly acquired data, making it a more effective decision-making tool.

2019/2020 Annual Groundwater Monitoring Report Project number: 60595649 Prepared for: Westinghouse Electric Company, LLC AECOM 2

To address high priority, targeted issues more quickly, CFFF also conducted other focused data collection under the RI including:

Addendum I to remove materials and intermodal (sealand) containers, investigate soil underneath and assure residential screening levels are met.

Addendum II to assess East Lagoon sludge characteristics and facilitate preparation of the East Lagoon Closure Plan which is currently under DHEC review.

An overall Tc-99 source investigation concluding that the impacts are historic and not the result of current operations.

In the past 2 years, Westinghouse also initiated risk reduction improvements including:

eliminated a nickel plating operation; eliminated the use of tetrachloroethylene (PCE);

re-designed the HF Spiking Station; installed a sentinel groundwater monitoring well network in the Chemical Area OU; significantly reduced stored materials via offsite disposal; and eliminated sources of potential storm water contamination from retired roof equipment.

In addition to the assessment activities performed by CFFF, DHEC conducted an assessment of potential CFFF impacts to fish in the Congaree River. DHECs Uranium and Fluoride in Fish from the Congaree River Technical Report No. 007-2020 dated May 2020 concluded:

Overall, within the context of the point in time of sample collection, target species and analytical "methods, no signal for uranium from the Westinghouse Nuclear Fuels (WNF) facility was discerned. A slight, apparent signal for fluoride was observed from the WNF facility but it was not overall statistically significant from the other locations. The target species, as indicated by the noted limitations, were indicated to be healthy from an ecological viewpoint and safe for human consumption from a public health protection viewpoint.

CFFF also performs routine environmental monitoring of gaseous and liquid effluents, surface water, groundwater, sediment, soil, vegetation and Congaree River fish tissue in addition to the activities being performed under the CA.

Groundwater sampling was completed during October 2019 and April 2020 to meet the ongoing groundwater monitoring requirements of the National Pollution Discharge Elimination System (NPDES) Permit SC0001848 and the CA between DHEC and CFFF. Details regarding the groundwater sample collection and QA\\QC procedures are contained within the AECOM Final RI Work Plan dated June 2019.

This report provides an overview of the site (Section 1.0), describes the sampling activities (Section 2.0), and presents the groundwater analytical results (Section 3.0). Conclusions and recommendations based on the results are discussed in Section 4.0. Cited references are provided in Section 5.0.

1.1 Site Location and Physical Setting Figures 1 through 3 illustrate the site features discussed below. The primary plant building is located approximately 2,700 feet southwest of Bluff Road on the northern portion of the property. The wastewater treatment plant (WWTP) is located near the southwest corner of the plant building. Treated wastewater is piped to the Congaree River where it is discharged under National Pollution Discharge Elimination System (NPDES) permit SC0001848 from a diffuser located along the bottom of the river at a location approximately 3 miles south of the developed portion of the property.

2019/2020 Annual Groundwater Monitoring Report Project number: 60595649 Prepared for: Westinghouse Electric Company, LLC AECOM 3

The SCRDI Bluff Road site (formerly known as South Carolina Recycling and Disposal, Inc.) is located across Bluff Road from the northern property boundary. According to information on the internet (Justia US Law - law.justia.com),

hazardous waste storage began on this property in late-1973 or early-1974, and operations ceased in 1982. This property was placed on the United States Environmental Protection Agencys (EPA) Superfund programs National Priority List (NPL) in 1983. Releases at SCRDI are not known to have impacted CFFF.

The developed area of the property is approximately 130-140 feet above mean sea level (MSL). Elevations drop to approximately 110 feet above MSL immediately south of the plant/WWTP area, on the Congaree River floodplain and Mill Creek, a tributary of the Congaree River. The change in elevation occurs abruptly along a bluff that defines the southern edge of the developed portion of the property.

The Gator Pond is a manmade pond constructed prior to CFFFs development of the site. It is located approximately 500 feet southwest of the WWTP within a step-down area of the bluff (Figures 2 and 3). The pond is fed by groundwater and does not have a constructed spillway. Water discharges from the pond through groundwater seepage or overland flow during periods of high precipitation.

Upper and Lower Sunset Lakes are located west and south of the pond and approximately 900 feet southwest of the WWTP (Figures 2 and 3). Sunset Lakes are located within a natural oxbow of Mill Creek. A manmade dam approximately 1,700 feet south of the WWTP backs up water in Mill Creek, creating Lower Sunset Lake. A second manmade dam cuts across Mill Creek approximately 1,000 feet southwest of the WWTP, creating Upper Sunset Lake.

The southern portion of the property, including the Gator Pond, Mill Creek, and Sunset Lakes are located within the floodplain of the Congaree River. Surface drainage at the site flows into several drainage ditches across the property and surrounding areas. These ditches merge and flow into Upper Sunset Lake.

1.2 Site Operational Background The main manufacturing activity is the fabrication of low-enriched uranium (U) fuel assemblies and components for the commercial nuclear power industry. The manufacturing process generates multiple wastewater streams which are treated by various physical/chemical/biological processes including WWTP lagoons prior to discharge to the Congaree River under a NPDES permit issued by DHEC.

Releases of COPCs have occurred from the wastewater treatment system and manufacturing operations. CFFF has assessed known releases and installed an extensive groundwater monitoring network beginning in the early 1980s.

Assessment activities have determined that releases have impacted soil and groundwater in locations largely confined to the immediate plant area. Various remediation efforts have been undertaken in response to the identified releases. No offsite impacts are known to have occurred.

1.3 Facility Operational Units The facility has been divided into eight operational units (OU) illustrated on Figure 4 in recognition of the different types of site activities and potential sources of impact. The OUs are identified as the Northern Storage Area, Mechanical Area of the plant building, Chemical Area of the plant building, West Lagoons Area, Wastewater Treatment Area, Sanitary Lagoon Area, Southern Storage Area and Western Storage Area. One area of concern (AOC), the Western Groundwater AOC, has also been identified. These OUs and the AOC are described in detail in the Final Remedial Investigation Work Plan dated June 2019 (AECOM, 2019a).

1.4 Geology and Hydrogeology The CFFF is located in the Upper Coastal Plain physiographic province. The CFFF is underlain by three hydrogeologic units: the surficial aquifer, Black Mingo aquifer, and Middendorf aquifer.

Groundwater in the surficial aquifer occurs under unconfined (water table) conditions and generally flows from areas of higher topography in the vicinity of the plant building towards areas of lower topography in the floodplain of the Congaree River along Mill Creek. Previously, the water table aquifer above the bluff and the water table aquifer below the bluff were described as the two separate aquifers: the surficial aquifer and the floodplain aquifer. Although the river terrace sediment above and below the bluff were deposited during different time periods, the deposits are of

2019/2020 Annual Groundwater Monitoring Report Project number: 60595649 Prepared for: Westinghouse Electric Company, LLC AECOM 4

similar lithology and have been found to be connected based on data collected during Phase I of the RI. Since groundwater flows continuously from above the bluff into the floodplain in a single surficial aquifer, groundwater above the Black Mingo confining clay will be referred to as the surficial aquifer henceforth.

Surficial aquifer sediments generally occur to a depth of 30 to 40 feet below land surface (BLS), both above and below the bluff, and consist of clay, silt or silty sand at the surface coarsening downward to coarse sand and gravel on top of the Black Mingo confining clay. Silt and clay lenses occur at varying depths with the coarsening downward sands of the surficial aquifer. One notable surficial aquifer total thickness anomaly was discovered during Phase I of the RI near the location of monitoring well W-95 (Figure 3) where there is over 80 feet of sediment above the Black Mingo confining clay. Further assessment in this area will be performed during Phase II of the RI.

Groundwater monitoring wells were installed at differing depths to assess COPC migration within the surficial aquifer.

Monitoring wells installed near the top of the surficial aquifer are designated as surficial aquifer upper zone monitoring wells, whereas wells installed on top of or within 5 feet of the Black Mingo confining clay are designated as surficial aquifer lower zone monitoring wells. One exception of the criteria above is well W-95. Monitoring well W-95 is designated as a surficial aquifer lower zone monitoring well because chlorinated volatile organic compounds (CVOCs) migrating within the lower zone of the surficial aquifer are found in it and the Black Mingo Formation is anomalously deep at this location.

There is a dynamic relationship between surface water in the ditches that transect the site above the bluff and groundwater in the upper zone of the surficial aquifer. The ditches continually or intermittently receive discharge of groundwater from the upper surficial aquifer depending on the elevation of the water table. The northern portions of the ditches are above the elevation of the seasonal high water table and thus the ditches at these locations are often dry. Runoff from precipitation that enters the dry portions of the ditches may infiltrate the water table, temporarily recharging the surficial aquifer. The southern portions of the ditches where the ditches are deeply incised may intermittently be above or below the water table, depending upon the extent of incisement and seasonal variations in the elevation of the water table. Middle portions of the ditches may recharge the shallow aquifer during low water table conditions and may receive groundwater discharge during high water table conditions.

The predominant direction of groundwater flow in the surficial aquifer is to the southwest with components of flow to the south and southeast. Discharge of groundwater to the deeply incised portions of the ditches appears to influence groundwater flow and COPC migration within the upper zone of the surficial aquifer. The Gator Pond also appears to influence COPC migration as evidenced by COPC impacts in surficial aquifer groundwater migrating in a more easterly or westerly direction in the vicinity of the Gator Pond.

The surficial aquifer is underlain by a confining unit composed of dry silt/clay and brittle shale of the upper Black Mingo Formation. Previous geologic cross sections (AECOM, 2013) and Phase I of the RI indicate that the Black Mingo confining clay ranges in thickness from 39 to 83 feet. Beneath the clay confining unit is an artesian sand aquifer within the lower Black Mingo Formation known as the Black Mingo aquifer. Groundwater flow in the Black Mingo aquifer is inferred to the southwest based upon groundwater elevations from the four monitoring wells that are screened within this aquifer.

The Middendorf Formation occurs below the Black Mingo Formation. Sediments of the Middendorf Formation generally consist of multi-colored clay interbedded with fine to coarse grained sand. Subsurface investigations at CFFF have not extended into the Middendorf aquifer since there is no potential that it has been impacted. The Middendorf aquifer is unconformably underlain by bedrock.

Previous hydraulic characterization by AECOM Technical Services, Inc. (AECOM) and Rust Environment and Infrastructure (Rust), estimated the average linear flow velocity in the surficial aquifer to be 0.42 feet per day or 153 feet per year. The potential for flow between the surficial aquifer and the Black Mingo aquifer was previously assessed to be downward at vertical hydraulic gradients ranging between 0.04 and 0.1 feet per foot (Rust, 1995 and AECOM, 2013). However, low moisture content and vertical hydraulic conductivities of less than 10-7 centimeters per second (S&ME, 1982) throughout the 39 to 83 foot thickness of the Black Mingo confining clay preclude migration of groundwater between the surficial aquifer and the Black Mingo aquifer which in turn precludes potential migration to the Middendorf Aquifer.

2019/2020 Annual Groundwater Monitoring Report Project number: 60595649 Prepared for: Westinghouse Electric Company, LLC AECOM 5

2.

Groundwater Monitoring The current monitoring well network consists of 90 monitoring wells (Figure 3). The monitoring well construction details are summarized on Table 1. Fall 2019 semi-annual sampling activities were completed by AECOM and CFFF personnel during October 2019. Spring 2020 semi-annual sampling activities were completed by AECOM and CFFF personnel during April 2020. Non-routine groundwater monitoring was conducted at monitoring well W-28 during 2019-2020. The non-routine groundwater sampling is described in further detail in Section 3.3. Monitoring activities were conducted in accordance with the requirements of the sites NPDES permit and by the procedures described in the Final Remedial Investigation Work Plan (AECOM, 2019a).

The depth to water in the monitoring wells was measured using electronic water level meters on October 14, 2019 and April 6, 2020. The water levels were converted to elevations and used to create potentiometric maps of the aquifer zones discussed in Section 3.1 below.

The monitoring wells were purged by low flow methodology using a peristaltic pump and water levels were monitored during purging. Groundwater quality indicator parameters of pH, specific conductance, dissolved oxygen, oxidation-reduction potential (ORP), turbidity, and temperature were monitored during the groundwater purging process and recorded on the Field Data Logs for Groundwater Sampling, which are included in Appendix A. Samples were collected once the parameters had stabilized in accordance with the low-flow sampling procedure in the Final Remedial Investigation Work Plan (AECOM, 2019a).

Upon collection, all groundwater samples were labeled, preserved on ice, and kept under chain-of-custody protocol until received at the analytical laboratory. The groundwater samples were analyzed by DHEC certified laboratories Pace Analytical Services, LLC (Pace), formerly known as Shealy Environmental Services, Inc. (Shealy), GEL Laboratories, LLC (GEL Labs), and the Westinghouse Chemical Laboratory as appropriate for the following analyses:

Target compound list (TCL) volatile organic compounds (VOCs) by EPA Method 8260B; TCL semi-VOCs by EPA Method 8270D; Target analyte list (TAL) metals by EPA Method 6010D/6020B; Nitrate by EPA Method 353.2; Ammonia by EPA Method 350.1; Fluoride by EPA Method 9056A; Gross Alpha by EPA Method 900.0; Gross Beta by EPA Method 900.0; Tritium by EPA 906.0 (Modified);

Isotopic U by DOEEML HASL-300 (U-02-RC Modified);

Isotopic U by EPA Method 200.8/200.2; and Tc-99 via DOE EML HASL-300 (Tc-02-RC Modified).

Laboratory analytical reports and chain-of-custody forms are included in Appendix B.

CFFF is transitioning from monitoring groundwater for gross alpha and gross beta to monitoring for isotopic U and Tc-

99. Gross alpha and gross beta are typically used as screening parameters because they can represent various radionuclide components. In the past, action levels were established for gross alpha and gross beta whereby additional contingent tests were initiated for isotopic U and Tc-99 if the action levels were exceeded. Results below the action levels would not have been further speciated, thus calling to question whether the low detection of gross alpha or gross beta was a result of site activities or other circumstances such as natural radionuclide presence.

CFFF has continued to monitor for gross alpha and gross beta but is relying on the site-specific COPC results for

2019/2020 Annual Groundwater Monitoring Report Project number: 60595649 Prepared for: Westinghouse Electric Company, LLC AECOM 6

isotopic U and Tc-99 to evaluate radionuclide concentrations in groundwater now that there is this data from four separate sampling events.

3.

Results The following sections summarize the results of the groundwater monitoring performed in October 2019 and April 2020.

3.1 Groundwater Flow The water level measurements on October 14, 2019 and April 6, 2020 were converted to water level elevations using existing monitoring well top-of-casing elevation data and are summarized in Table 2. The water level elevations from monitoring wells screened in the surficial aquifer - upper zone and wells screened in the Black Mingo aquifer were used to prepare the potentiometric maps for the surficial aquifer and Black Mingo aquifer for the October 2019 and April 2020 monitoring periods (Figures 5 through 8).

3.1.1 Surficial Aquifer Based on the surficial aquifer potentiometric maps for October 14, 2019 and April 6, 2020 (Figures 5 and 6, respectively), groundwater flow in the unconfined surficial aquifer - upper zone is generally to the southwest with components of flow to the west and south. These surficial aquifer potentiometric contours and flow directions are similar to previous results.

3.1.2 Black Mingo Aquifer Based on the Black Mingo Aquifer potentiometric maps for October 14, 2019 and April 6, 2020 (Figures 7 and 8, respectively), groundwater in the Black Mingo aquifer is generally to the southwest. The Black Mingo aquifer potentiometric contours and flow directions are similar to previous results.

3.2 Groundwater Quality Groundwater sampling indicator parameters measured in the field during the well purging and sampling are presented in Table 3. The groundwater sampling logs are included in Appendix A. Laboratory analytical reports are included in Appendix B and the analytical results for the monitoring wells are summarized in Table 4. Historic analytical data is summarized in Table C-1 included in Appendix C.

Historic data trends for nitrate, fluoride, gross alpha and gross beta have been included in previous annual reports.

This report includes historic data trends for nitrate, fluoride, U, and Tc-99 (Appendix D). As discussed in Section 2.0, the U concentration trends are included to replace the former trend analysis for gross alpha and the Tc-99 concentration trends are included to replace the former trend analysis for gross beta.

Based on previous groundwater assessment activities, COPCs in groundwater are CVOCs, nitrate, fluoride, U, and Tc-99. Also, there is currently no evidence that there are ongoing releases of COPCs.

3.2.1 Chlorinated Volatile Organic Compounds (CVOCs)

Four CVOCs (tetracholoroethylene [PCE], tricholoroethylene [TCE], cis-1,2-dicholoroethene [cis-1,2-DCE], and vinyl chloride [VC]) were detected in the upper and lower zones of the surficial aquifer. TCE, cis-1,2-DCE, and VC are breakdown products of the dechlorination of PCE. CVOCs were not detected in the groundwater samples collected from the Black Mingo aquifer monitoring wells.

3.2.1.1 PCE PCE was detected in groundwater at concentrations at or above its maximum contaminant level (MCL) of 5.0 micrograms per liter (µg/L) in groundwater from 21 of the 86 surficial aquifer monitoring wells (Table 4). There are three PCE plumes at CFFF contained within the property in the surficial aquifer. These CVOC plumes are generally

2019/2020 Annual Groundwater Monitoring Report Project number: 60595649 Prepared for: Westinghouse Electric Company, LLC AECOM 7

referred to as the Western Groundwater AOC, the main plume, and the eastern plume. These plumes are depicted on Figures 9 through 12. PCE was not detected in groundwater samples from the four Black Mingo monitoring wells.

Surficial Aquifer - Upper Zone Figures 9 and 10 illustrate the PCE concentrations in the surficial aquifer - upper zone during the October 2019 and April 2020 sampling periods, respectively. The highest PCE concentrations in surficial aquifer - upper zone wells were from wells W-39, W-41R, and W-66 in the main PCE plume at concentrations ranging from 180 µg/L to 480

µg/L. PCE was detected in the samples from monitoring well W-89 in the Western Groundwater AOC at concentrations of 2.1 µg/L and 6.7 µg/L during October 2019 and April 2020, respectively.

The main PCE plume in the surficial aquifer - upper zone appears to emanate from an area between West Lagoon 2 (WL2) and the plant building. Groundwater in this area migrates to the southwest. The southern PCE plume in the surficial aquifer - upper zone emanates from the southern developed areas of the site and extends to the south. It is currently unknown whether the Western Groundwater AOC PCE plume is the result of groundwater migration from the developed area of the facility or another source. Phase II RI investigation activities will assess the three plume areas further.

Surficial Aquifer - Lower Zone Figures 11 and 12 illustrate the PCE concentrations in the surficial aquifer - lower zone during the October 2019 and April 2020 sampling periods, respectively. Two PCE plumes are present in the surficial aquifer - lower zone, the Western Groundwater AOC and the main plume. In the surficial aquifer - lower zone, the main PCE plume was observed directly west of the facility in the same area as the main PCE plume observed in the surficial aquifer -

upper zone, however with a greater aerial extent. The highest PCE concentrations in the surficial aquifer - lower zone were from wells W-33, W-48, W-65, and RW-2 in the main PCE plume at concentrations ranging from 140 µg/L to 300

µg/L. PCE was detected in the samples from monitoring wells W-19B and W-68 in the Western Groundwater AOC at concentrations ranging from 110 µg/L to 150 µg/L for October 2019 and April 2020 data.

The main PCE plume in the surficial aquifer - lower zone appears to emanate from an area between WL2 and the plant building and migrates to the southwest. It is currently unknown whether the Western Groundwater AOC PCE plume is the result of groundwater migration from the developed area of the facility or another source. Phase II RI investigation activities will assess the three plume areas further.

3.2.1.2 TCE TCE was detected in groundwater at concentrations at or above its MCL of 5.0 µg/L from 10 of the 86 surficial aquifer monitoring wells (Table 4). There are four TCE plumes at CFFF in the surficial aquifer. These CVOC plumes are generally referred to as the Western Groundwater AOC, the main plume, the eastern plume, and a plume near the southwest corner of the plant building. These plumes are depicted on Figures 13 through 16. TCE was not detected in samples from the four Black Mingo monitoring wells.

Surficial Aquifer - Upper Zone The surficial aquifer - upper zone middle and eastern TCE plumes are in the same general locations as the corresponding PCE plumes but with a smaller aerial extent during the October 2019 and April 2020 sampling periods (Figures 13 and 14, respectively). TCE exceeded the MCL in groundwater samples from monitoring wells W-39, W-41R, and W-66 in the main TCE plume, W-67 in the eastern TCE plume, and monitoring wells W-38 and W-76 near the southwest corner of the plant building.

Surficial Aquifer - Lower Zone In the surficial aquifer - lower zone, the main TCE plume was observed directly west of the facility extending in a southwestern direction in the same general location as the main PCE plume. Figures 15 and 16 illustrate the TCE concentrations in the surficial aquifer - lower zone during the October 2019 and April 2020 sampling periods, respectively. The TCE MCL was exceeded in the main TCE plume in groundwater from surficial aquifer - lower zone wells W-33, W-65, W-87, and RW-2R in October 2019 and January 2020 at concentrations ranging from 8.3 µg/L to 84 µg/L. The greatest TCE concentration was observed in the groundwater from W-65 at a concentration of 84 µg/L during the April 2020 sampling event.

2019/2020 Annual Groundwater Monitoring Report Project number: 60595649 Prepared for: Westinghouse Electric Company, LLC AECOM 8

3.2.1.3 Cis-1,2-Dichloroethene Concentrations of cis-1,2 DCE did not exceed the MCL of 70 µg/L in groundwater from the 90 monitoring wells. Cis-1,2-DCE was detected at concentrations ranging from 1.0 µg/L to 22 µg/L in groundwater from 20 surficial aquifer monitoring wells during the October 2019 and April 2020 sampling periods.

3.2.1.4 Vinyl Chloride Groundwater from one monitoring well (W-95) contained VC at 2.9 µg/L during the October 2019 and April 2020 sampling periods, which exceeds the VC MCL of 2 µg/L.

3.2.2 SVOCs SVOCS were not detected in groundwater above MCLs in the monitoring well network..

3.2.3 Nitrate Nitrate was detected in groundwater at concentrations at or above its MCL of 10 milligrams per liter (mg/L) from 22 of the 90 monitoring wells (Table 4). Figures 17 and 18 illustrate the nitrate concentrations for the October 2019 and April 2020 sampling periods, respectively. The highest nitrate concentrations were observed in the groundwater collected from surficial aquifer - lower zone monitoring well W-18R near the southwest corner of the South Lagoon at concentrations of 770 mg/L and 790 mg/L during the October 2019 and April 2020 sampling periods, respectively. The aerial extent of the nitrate plume is primarily in the area of the facility WWTP and extends to areas to the west, southwest, and south. Nitrate was detected in groundwater from one Black Mingo aquifer monitoring well (W-71) below its MCL at a concentration of 0.021 mg/L in October 2019. Nitrate is a naturally occurring compound and the detected concentration in monitoring well W-71 is orders of magnitude below the MCL indicating that this detection is not likely the result of facility operations. Phase II RI investigation activities will assess nitrate plume areas further.

Figure D1 in Appendix D illustrates nitrate concentration trends for groundwater from 12 monitoring wells. Based on a review of time-series plots from 2015-2020, the site nitrate plume is stable. Groundwater from these monitoring wells were selected for trend analysis by including wells that are within the plume and along the edges of the plume.

Since 2015, nitrate concentrations have decreased in groundwater from monitoring wells, W-10, W-14, W-29, and W-

38. These monitoring wells are upgradient to sidegradient of the area of highest nitrate concentrations. Nitrate concentrations in groundwater from monitoring well W-47 previously indicated a slow increasing trend through 2018 but has decreased since then. This monitoring well is along the center line of the migration of nitrate in groundwater.

Groundwater trends from the remaining monitoring wells indicate that nitrate concentrations remained stable and within historic ranges over the last five years.

3.2.4 Fluoride Fluoride was detected at concentrations at or above its MCL of 4 mg/L in groundwater from 15 of the 90 monitoring wells (Table 4). Fluoride is a naturally occurring compound and many of the detected concentrations in groundwater were orders of magnitude below the MCL indicating that these detections are not likely resulting from facility operations. Figures 19 and 20 illustrate the fluoride concentrations for the October 2019 and April 2020 sampling events, respectively. The greatest fluoride concentration was observed in the groundwater from upper surficial well W-78 at concentrations of 13.4 mg/L and 11.3 mg/L during the October 2019 and April 2020 sampling periods, respectively. The fluoride plume exceeding the MCL in the surficial aquifer is primarily in the southern area of the plant building and the WWTP and extends to the south toward the Gator Pond and Lower Sunset Lake. Fluoride was detected in groundwater from the four Black Mingo aquifer monitoring wells below its MCL at concentrations ranging from 0.003 mg/L to 0.084 mg/L. Again, it is not likely that these detections are resulting from facility operations. Phase II RI investigation activities will assess fluoride plume areas further.

Figure D2 in Appendix D illustrates fluoride concentration trends for groundwater from 10 monitoring wells. Based on a review of time-series plots from 2015-2020, the site fluoride plume is stable. Groundwater from these monitoring wells were selected for trend analysis by including wells that were within the plume and along the edges of the plume.

Fluoride concentrations in W-7A, W-13R, W-18R, and W-30 decreased from 2015 until April 2020. These monitoring wells are in the center of the area of impact near the lagoons or downgradient of the center of the fluoride impact.

Fluoride concentrations from monitoring well W-29 increased from April 2017 to April 2018 but groundwater from this

2019/2020 Annual Groundwater Monitoring Report Project number: 60595649 Prepared for: Westinghouse Electric Company, LLC AECOM 9

well has indicated a decreasing trend since the high in April 2018. This well is upgradient of the center of the area of impact near the lagoons. Fluoride concentrations in groundwater from monitoring wells W-18 and W-47 have indicated an overall decreasing trend. These monitoring wells are in the center of the area of impact near the lagoons or downgradient of the center of the fluoride impact. Groundwater trends from the remaining monitoring wells indicate that fluoride concentrations remained stable and within historic concentration ranges.

3.2.5 Uranium Total U was detected in groundwater at concentrations at or above its MCL of 30 µg/L from 3 of the 90 monitoring wells (Table 4). The exceedance of the groundwater MCL for U is localized to two areas adjacent to the plant building, one area on the west side of the building near the southwest corner (monitoring wells W-55 and W-56) and another area on the south side of the building (monitoring well W-77). Figures 21 and 22 illustrate the total U concentrations detected during the October 2019 and the April 2020 sampling periods, respectively. The highest total U concentration of 264 µg/L was detected in groundwater from monitoring well W-77 during the April 2020 sampling event. The next closest downgradient well, monitoring well W-28, is 25 feet away and contains total U at concentrations less than 1.0 ug/L.

U was detected in groundwater from the four Black Mingo aquifer monitoring wells at concentrations below its MCL ranging from 0.0695 µg/L to 0.165 µg/L. Total U occurs naturally in groundwater in South Carolina. A study performed in the Aiken, SC and Augusta, GA area reported an average background groundwater U concentration from private water supply wells of 0.35 µg/L (Westinghouse Savannah River Company, 1992). Another study of state-wide groundwater analytical results from private water supply wells using statistical analysis predicted an average background groundwater U concentration of 1.26 µg/L (Wagner, S.E., et al). Private water supply wells are typically installed in the aquifer below the surficial aquifer. The total U detected in groundwater from the Black Mingo wells is typical of regional background concentrations and not likely the result of facility operations.

The U trend plot is included as Figure D3 in Appendix D. Groundwater from these monitoring wells were selected for trend analysis by including wells that were within and near the localized total U detections. The U concentration trends are included to replace the former trend analysis for gross alpha in previous annual reports. The monitoring wells used to create the trend plots have been sampled three to five times for U since October 2018. Therefore, Figure D3 represents recent, short-term trends. Of the monitoring wells exhibiting U concentrations greater than the MCL, U decreased in samples from wells W-55 and W-56 over three sampling periods and increased in samples from W-77 over two sampling periods.

3.2.6 Tc-99 Tc-99 was detected above its MCL of 900 picocuries per liter (pCi/L) in the groundwater samples collected from two surficial aquifer monitoring wells (W-6 and W-11). Figures 23 and 24 illustrate the Tc-99 concentrations detected during the October 2019 and the April 2020 sampling periods, respectively. Tc-99 concentrations detected in groundwater from monitoring wells W-6 and W-11 ranged from 2,440 pCi/L to 3440 pCi/L from October 2019 to April 2020. The aerial extent of the Tc-99 exceeding the MCL is within the WWTP area and the Southern Storage Area.

The aerial extent of the Tc-99 plume at concentrations below the MCL extends from the WWTP area toward the west, southwest, and southeast. Tc-99 was not detected in groundwater samples from the four Black Mingo monitoring wells. Additional assessment is planned to further define the extent of Tc-99 in groundwater. Phase II RI investigation activities will assess Tc-99 plume areas further.

The Tc-99 trend plot is included as Figure D4 in Appendix D. Groundwater from these monitoring wells were selected for trend analysis by including wells that were within the plume and along the edges of the plume. The Tc-99 concentration trends are included to replace the former trend analysis for gross beta in previous annual reports. Tc-99 concentrations in monitoring wells sampled since 2015 have fluctuated over time but have generally decreased or remained stable. Groundwater from monitoring wells W-6 and W-11 has been sampled since 2018 with Tc-99 remaining stable in both wells. Concentration trends from the remaining monitoring wells that were plotted also remain stable.

2019/2020 Annual Groundwater Monitoring Report Project number: 60595649 Prepared for: Westinghouse Electric Company, LLC AECOM 10 3.2.7 Other Monitoring Requirements Tritium is not a COPC for the CFFF site. CFFF is a fuel fabrication facility that manufactures nuclear fuel from un-irradiated uranium which does not contain tritium. Tritium is a byproduct of a nuclear criticality that is produced after the nuclear fuel is irradiated in a nuclear reactor at the CFFFs customer site.

As required by the NPDES permit, CFFF includes analysis for tritium in groundwater samples from 20 monitoring wells. Based on the laboratory results, tritium was not detected above the laboratory minimum detectible concentration during the 2019-2020 monitoring period or during previous periods (Table 4 and Appendix C). The laboratory results further demonstrate that tritium is not present in groundwater at CFFF as a result of fuel manufacturing activities.

3.3 Non-Routine Groundwater Sampling During 2019-2020, non-routine groundwater sampling was conducted at CFFF to coincide with additional investigative activities at the site. Groundwater analytical results from non-routine groundwater sampling events are displayed in Table 4.

Monitoring Well W-28 In July of 2018, the site had a leak from Hydrofluoric Acid Spiking Station #2 and subsequently remediated the impacted area. To monitor the potential migration of groundwater impact associated with this release, the site has sampled groundwater from downgradient monitoring well W-28 on a quarterly basis.

4.

Conclusions and Recommendations 4.1 Conclusions The following conclusions are based upon review of the groundwater monitoring data collected during October 2019 and April 2020 sampling periods:

Groundwater flow in the unconfined surficial aquifer is generally to the southwest with components of flow to the west and south. These surficial aquifer potentiometric contours and flow directions are similar to previous results. Groundwater flow in the Black Mingo aquifer is generally to the southwest. The Black Mingo aquifer potentiometric contours and flow directions are similar to previous results.

CVOCs detected during October 2019 and April 2020 exceeding MCLs were primarily PCE and, to a lesser extent, TCE. Two additional breakdown products of PCE reductive dechlorination, cis-1,2 DCE and VC, were detected in groundwater at the CFFF site at concentrations below the MCL for cis-1,2 DCE and above the MCL for VC. Trans-1,2-Dichloroethene was not detected in groundwater from the monitoring wells.

The groundwater analytical results indicate that there are PCE and TCE groundwater plumes in the upper and lower zones of the surficial aquifer west of the plant building and in the surficial aquifer - upper zone south of the plant building. The CVOC plumes have been referred to as the Western Groundwater AOC, main plume, eastern plume, and a plume near the southwest corner of the plant building.

The main CVOC plume appears to emanate from a source(s) between the plant building and WL2. Elevated PCE concentrations in the main CVOC plume extend from the surficial aquifer - upper zone to the surficial aquifer - lower zone. Concentrations of TCE above its MCL occur primarily in the surficial aquifer - lower zone.

It is currently not known whether the PCE concentrations in the Western Groundwater AOC are the result of the plume emanating from the WL2/plant area or another source. There are no known manufacturing processes in this area that currently or historically used PCE. Additional assessment of the Western Groundwater AOC will occur in Phase II of the RI.

The eastern CVOC plume is located in the southern portion of the developed area of the facility and upgradient of the Gator Pond. PCE concentrations above the MCL within this plume appear to be within the surficial aquifer

2019/2020 Annual Groundwater Monitoring Report Project number: 60595649 Prepared for: Westinghouse Electric Company, LLC AECOM 11

- upper zone only, based on previous assessment (AECOM, 2017). PCE concentrations in this plume are an order of magnitude lower than the PCE concentrations in the middle plume and do not appear to be related to a specific potential source area of the CFFF site. There are no known processes in this area that currently or historically used PCE.

Nitrate concentrations during October 2019 and April 2020 exceeding MCLs were in areas west, southwest, and south of the WWTP. The highest nitrate concentrations were observed in the groundwater samples collected from surficial monitoring wells south of the South Lagoon area of the WWTP.

Fluoride concentrations during October 2019 and April 2020 exceeding MCLs were in areas west, southwest, and south of the WWTP. The highest fluoride concentrations were observed in the groundwater samples collected from surficial monitoring wells in the area of the southern portion of the WWTP. The aerial extent of the fluoride plume is primarily in the area of the facility WWTP and extends to areas to the west, southwest, and south.

U concentrations exceeded the MCL during the October 2019 and April 2020 in three surficial monitoring wells located near the southwest side of the facility building and one monitoring well located near the south end of the building. The exceedance of the U MCL in groundwater is localized near the plant building and is delineated by the existing monitoring well network.

Tc-99 concentrations exceeded the MCL during October 2019 and April 2020 in two surficial aquifer monitoring wells at stable concentrations.

Based upon historical and current groundwater analytical results, no off-site impacts of COPCs are known or believed to have occurred.

4.2 Recommendations Based on the results of the Phase I RI work performed under the CA with the DHEC Bureau of Land and Waste Management (AECOM,2020b), and subsequent meetings with DHEC, Westinghouse is planning to perform additional groundwater assessment as outlined in the Phase II Remedial Investigation Work Plan (AECOM, 2020c).

The Phase II work will include the installation of additional monitoring wells. These new wells will be included in the semi-annual groundwater monitoring program as part of the CA, and the results will also be included in the 2021 annual report.

Based upon the above conclusions, continued semiannual monitoring in accordance with the NPDES Permit and the CA is recommended. The next groundwater sampling periods are Fall 2020 and Spring 2021.

5.

References AECOM, 2013. Remedial Investigation Report, Westinghouse Electric Company, Columbia Fuel Fabrication Facility, Richland County, South Carolina, December 31.

AECOM, 2014. Preliminary Baseline Risk Assessment, Westinghouse Columbia Fuel Fabrication Facility, 5801 Bluff Road, Hopkins, South Carolina, February 7, 2014.

AECOM, 2017. CVOC Field Screening Report, Westinghouse Columbia Fuel Fabrication Facility, 5801 Bluff Road, Hopkins, South Carolina, February 2020.

AECOM, 2019a. Final Remedial Investigation Work Plan, Westinghouse Columbia Fuel Fabrication Facility, 5801 Bluff Road, Hopkins, South Carolina, June 2019.

AECOM, 2019b. Preliminary Human Health Risk Assessment, Westinghouse Columbia Fuel Fabrication Facility, 5801 Bluff Road, Hopkins, South Carolina, March 2019.

AECOM, 2020a. Interim Remedial Investigation Data Summary Report, Westinghouse Columbia Fuel Fabrication Facility, 5801 Bluff Road, Hopkins, South Carolina, February 2020.

2019/2020 Annual Groundwater Monitoring Report Project number: 60595649 Prepared for: Westinghouse Electric Company, LLC AECOM 12 AECOM, 2020b. Final Interim Remedial Investigation Data Summary Report, Westinghouse Columbia Fuel Fabrication Facility, 5801 Bluff Road, Hopkins, South Carolina, July 2020.

AECOM, 2020c. Phase II Remedial Investigation Work Plan, Westinghouse Columbia Fuel Fabrication Facility, 5801 Bluff Road, Hopkins, South Carolina, September 2020.

Leidos, 2020. Columbia Fuel Fabrication Facility, Tc-99 Source Investigation Report, July 2020.

JUSTIA US Law website (USA/SCDHEC vs SCRDI et al. lawsuit), http://law.justia.com/cases/federal/district-courts/FSupp/653/984/2400694/, reviewed by Mr. Jeremy Grant of AECOM on September 24, 2017.

Rust, 1995. Conceptual Design Report, Westinghouse Commercial Fuel Division, Columbia, South Carolina, September 8, 1995.

S&ME, 1982. Ground-Water Hydrology of the Westinghouse Electric Corporation Plant, Richland County, South Carolina, March 1, 1982.

2019/2020 Annual Groundwater Monitoring Report Project number: 60595649 Prepared for: Westinghouse Electric Company, LLC AECOM Tables

Table 1 Monitoring Well Construction Details Westinghouse Columbia Fuel Fabrication Facility AECOM Project No. 60595649 Well Number Northing Easting Date Installed Ground Surface Elevation (ft msl)

Top of Casing Elevation (ft msl)

Casing Stickup (ft)

Well Diameter (in)

Casing Type Total Depth (ft bgs)

Screen Length (ft)

Screen Interval (ft bgs)

Classification W-RW-1 745689.8390 2024255.5150 4/1/1995 136.00 136.95 0.95 4.0 Steel 32.20 10 22.2-32.2 Surficial - Lower Zone W-RW2 745325.1547 2023458.2190 3/10/1995 136.98 139.93 2.95 4.0 Steel 28.43 10 19-29.2 Surficial - Lower Zone W-3A 744340.2273 2023926.2926 6/11/1985 117.64 120.08 2.44 2.0 PVC 82.86 10 72.5-82.5 Black Mingo W-4 744343.6686 2023959.5730 1977 116.50 116.09

-0.41 4.0 PVC 15.01 2

10-12 Surficial - Upper Zone W-6 744963.2941 2024109.6154 5/15/1980 136.96 136.46

-0.50 2.0 PVC 27.78 5

23.5-28.5 Surficial - Lower Zone W-7A 744907.4275 2023872.2237 2/19/1992 132.94 135.06 2.12 2.0 PVC 17.92 5

13-18 Surficial - Upper Zone W-10 744897.8502 2023659.8964 5/14/1980 136.89 136.81

-0.08 2.0 PVC 22.30 5

18.5-23.5 Surficial - Upper Zone W-11 744743.0468 2023914.5566 5/14/1980 138.45 140.76 2.31 2.0 PVC 24.90 3

25.5-28.5 Surficial - Upper Zone W-13R 744648.7070 2024279.2522 10/8/2010 136.38 136.13

-0.25 2.0 PVC 20.52 5

15-20 Surficial - Upper Zone W-14A 744603.1956 2024478.6507 5/4/1988 136.22 137.83 1.61 2.0 PVC 28.91 5

23.5-28.5 Surficial - Upper Zone W-15 744663.4226 2023716.7929 5/15/1980 126.67 127.90 1.23 2.0 PVC 20.66 5

13.5-18.5 Surficial - Upper Zone W-16 744602.3196 2024060.2560 5/15/1980 125.64 124.93

-0.71 2.0 PVC 13.23 3

15.5-18.5 Surficial - Upper Zone W-17 745055.2186 2023785.3818 5/30/1980 137.57 139.27 1.70 2.0 PVC 27.92 5

23.5-28 Surficial - Lower Zone W-18R 745012.6889 2023939.2527 Unknown 137.15 136.71

-0.44 2.0 PVC 27.63 5

12.5-17.5 Surficial - Lower Zone W-19B 746172.6764 2022552.9543 3/17/1995 140.58 142.85 2.27 4.0 PVC 40.73 10 30-40.5 Surficial - Lower Zone W-20 743739.6310 2022975.3834 7/10/1980 113.27 116.16 2.89 2.0 PVC 15.66 5

11.5-16.3 Surficial - Upper Zone W-22 744960.9243 2024116.3963 7/12/1980 137.08 136.51

-0.57 2.0 PVC 15.10 5

13.4-17.8 Surficial - Upper Zone W-23R 744674.7363 2024851.2620 7/22/2011 137.45 140.47 3.02 2.0 PVC 20.93 5

15.5-20.5 Surficial - Upper Zone W-24 746742.5552 2027344.7554 7/9/1980 139.83 141.94 2.11 2.0 PVC 15.00 5

10.1-15.1 Surficial - Upper Zone W-25 742114.3330 2022728.9859 7/9/1980 114.98 115.88 0.90 2.0 PVC 27.25 5

22.9-27.7 Surficial - Upper Zone W-26 744855.2926 2023417.6899 7/11/1980 140.59 142.21 1.62 2.0 PVC 30.64 5

25.5-30.5 Surficial - Upper Zone W-27 744383.9028 2023708.2286 7/13/1980 120.22 121.87 1.65 2.0 PVC 14.72 5

14.1-18.9 Surficial - Upper Zone W-28 745121.7794 2024317.4127 7/13/1980 136.98 138.88 1.90 2.0 PVC 15.30 5

9.8-14.7 Surficial - Upper Zone W-29 745182.7704 2024101.6410 7/12/1980 136.96 138.61 1.65 2.0 PVC 13.95 5

10-15.1 Surficial - Upper Zone W-30 745095.1563 2024150.8369 7/11/1980 136.87 138.81 1.94 2.0 PVC 14.86 5

10.2-15.2 Surficial - Upper Zone W-32 744742.1011 2023919.8088 7/15/1980 138.33 140.61 2.28 2.0 PVC 21.75 5

17-22.5 Surficial - Upper Zone W-33 745402.9946 2023548.6640 7/15/1980 138.06 139.33 1.27 2.0 PVC 22.88 5

15.1-20.7 Surficial - Lower Zone W-35 745716.6972 2024227.9328 2/18/1992 136.59 139.07 2.48 2.0 PVC 20.35 5

16-21 Surficial - Upper Zone W-36 746084.8252 2024573.1745 2/19/1992 134.16 136.29 2.13 2.0 PVC 19.77 5

15-20 Surficial - Upper Zone W-37 745407.3901 2024230.7318 2/11/1992 136.58 139.04 2.46 2.0 PVC 20.46 5

15.5-20.5 Surficial - Upper Zone W-38 745250.3065 2024192.9679 2/18/1992 136.71 136.51

-0.20 2.0 PVC 20.16 5

15-20 Surficial - Upper Zone W-39 745587.4130 2023656.6724 1/27/1994 139.08 141.15 2.07 2.0 PVC 23.17 10 12-22 Surficial - Upper Zone W-40 745646.5324 2024112.4795 7/18/1984 136.42 139.26 2.84 2.0 PVC 14.39 10 5-15 Surficial - Upper Zone W-41R 745372.8885 2023252.5925 Unknown 131.02 133.81 2.79 2.0 PVC 24.33 10 14-24 Surficial - Upper Zone W-42 745072.3463 2023203.3177 1/27/1994 137.83 140.96 3.13 2.0 PVC 29.91 10 20-30 Surficial - Upper Zone Page 1 of 3

Table 1 Monitoring Well Construction Details Westinghouse Columbia Fuel Fabrication Facility AECOM Project No. 60595649 Well Number Northing Easting Date Installed Ground Surface Elevation (ft msl)

Top of Casing Elevation (ft msl)

Casing Stickup (ft)

Well Diameter (in)

Casing Type Total Depth (ft bgs)

Screen Length (ft)

Screen Interval (ft bgs)

Classification W-43 745904.3053 2023600.1186 1/27/1994 138.09 141.33 3.24 2.0 PVC 21.12 10 10.5-20.5 Surficial - Upper Zone W-44 745579.8931 2022950.1077 2/1/1994 131.93 134.86 2.93 2.0 PVC 27.04 10 16-26 Surficial - Lower Zone W-45 745644.0322 2024296.0965 7/18/1984 137.20 140.02 2.82 2.0 PVC 15.38 10 6-16 Surficial - Upper Zone W-46 745154.5936 2023494.4570 3/27/1995 132.39 134.74 2.35 4.0 PVC 25.84 10 15.5-25.5 Surficial - Upper Zone W-47 744633.7657 2023515.8706 3/31/1995 140.70 141.90 1.20 4.0 PVC 45.60 10 34.3-44.8 Surficial - Lower Zone W-48 744913.2226 2023290.4438 3/30/1995 139.74 142.56 2.82 4.0 PVC 41.30 10 30.7-41.3 Surficial - Lower Zone W-49 745073.2286 2023192.6302 3/15/1995 137.82 140.25 2.43 2.0 PVC 117.77 10 105-115 Black Mingo W-50 745637.2219 2024107.3993 3/21/1995 136.79 139.58 2.79 2.0 PVC 125.41 10 114.5-124.5 Black Mingo W-51 745583.8582 2024270.8300 9/19/2018 136.67 136.51

-0.16 2.0 PVC 14.66 5

10-15 Surficial - Upper Zone W-52 745542.3624 2024260.1657 9/19/2018 136.71 136.19

-0.52 2.0 PVC 15.55 5

10-15 Surficial - Upper Zone W-53 745495.9968 2024247.5619 9/19/2018 136.83 136.54

-0.29 2.0 PVC 15.74 5

10-15 Surficial - Upper Zone W-54 745442.5511 2024229.9796 9/19/2018 136.79 136.52

-0.27 2.0 PVC 15.85 5

10-15 Surficial - Upper Zone W-55 745397.6509 2024214.0049 9/20/2018 136.90 136.63

-0.27 2.0 PVC 15.24 5

10-15 Surficial - Upper Zone W-56 745351.3097 2024203.7460 9/20/2018 136.83 136.68

-0.15 2.0 PVC 15.11 5

10-15 Surficial - Upper Zone W-57 745307.4270 2024190.7853 9/20/2018 136.90 136.73

-0.17 2.0 PVC 15.11 5

10-15 Surficial - Upper Zone W-58 745254.0864 2024176.3347 9/18/2018 136.85 136.37

-0.48 2.0 PVC 15.49 5

10-15 Surficial - Upper Zone W-59 745219.3681 2024165.8802 9/18/2018 136.10 136.42 0.32 2.0 PVC 14.65 5

10-15 Surficial - Upper Zone W-60 745835.5835 2023286.8131 10/8/2018 137.25 140.20 2.95 2.0 PVC 37.86 5

32-37 Surficial - Lower Zone W-61 745829.2570 2023288.2599 10/9/2018 137.34 140.60 3.26 2.0 PVC 23.51 10 13-23 Surficial - Upper Zone W-62 745485.4613 2022726.0792 10/9/2018 125.63 128.38 2.75 2.0 PVC 24.85 5

19-24 Surficial - Lower Zone W-63 745098.1342 2023019.4184 10/10/2018 138.78 141.02 2.24 2.0 PVC 41.91 5

37-42 Surficial - Lower Zone W-64 744643.8030 2023511.3331 10/10/2018 140.15 142.75 2.60 2.0 PVC 31.61 10 21-31 Surficial - Upper Zone W-65 745693.7040 2024027.4543 10/12/2018 138.17 140.95 2.78 2.0 PVC 31.59 5

26.5-31.5 Surficial - Lower Zone W-66 745687.8186 2024027.1699 10/12/2018 138.01 140.91 2.90 2.0 PVC 22.34 10 12-22 Surficial - Upper Zone W-67 744459.5852 2024485.7938 10/15/2018 132.60 135.26 2.66 2.0 PVC 31.81 10 21-31 Surficial - Upper Zone W-68 745329.2457 2022496.2174 11/1/2018 113.40 116.53 3.13 2.0 PVC 18.14 5

13-18 Surficial - Lower Zone W-69 745726.9177 2026064.2900 6/11/2019 137.67 140.64 2.97 2.0 PVC 18.08 10 7.75-17.75 Surficial - Upper Zone W-70 745719.2209 2026062.8740 6/20/2019 138.02 141.00 2.98 2.0 PVC 48.92 5

44-49 Surficial - Lower Zone W-71 745716.6462 2026052.3340 9/19/2019 137.96 140.72 2.77 2.0 PVC 103.03 10 93-103 Black Mingo W-72 745450.2503 2024162.6920 6/30/2019 136.81 136.29

-0.53 2.0 PVC 15.00 10 5-15 Surficial - Upper Zone W-73 745339.3056 2024166.2500 6/30/2019 136.85 136.45

-0.40 2.0 PVC 16.09 10 5-15 Surficial - Upper Zone W-74 745325.1257 2024067.1720 9/17/2019 136.64 139.93 3.29 2.0 PVC 30.60 5

25-30 Surficial - Lower Zone W-75 745317.2335 2024064.7580 9/17/2019 136.60 139.85 3.25 2.0 PVC 15.33 10 5-15 Surficial - Upper Zone W-76 745181.1851 2024223.5230 6/29/2019 137.04 136.85

-0.19 2.0 PVC 15.12 10 5-15 Surficial - Upper Zone W-77 745158.9297 2024346.1090 9/18/2019 136.85 136.53

-0.32 2.0 PVC 15.67 10 5-15 Surficial - Upper Zone Page 2 of 3

Table 1 Monitoring Well Construction Details Westinghouse Columbia Fuel Fabrication Facility AECOM Project No. 60595649 Well Number Northing Easting Date Installed Ground Surface Elevation (ft msl)

Top of Casing Elevation (ft msl)

Casing Stickup (ft)

Well Diameter (in)

Casing Type Total Depth (ft bgs)

Screen Length (ft)

Screen Interval (ft bgs)

Classification W-78 745117.7529 2024371.0300 9/19/2019 136.75 136.31

-0.44 2.0 PVC 15.57 10 5-15 Surficial - Upper Zone W-79 745200.3957 2024450.2660 6/29/2019 136.49 136.12

-0.38 2.0 PVC 15.66 10 5-15 Surficial - Upper Zone W-80 745024.3899 2024414.6850 6/29/2019 136.34 135.87

-0.47 2.0 PVC 15.62 10 5-15 Surficial - Upper Zone W-81 744938.6049 2024469.8490 6/29/2019 136.81 136.43

-0.39 2.0 PVC 15.74 10 5-15 Surficial - Upper Zone W-82 744895.9297 2024594.1720 6/29/2019 136.57 136.23

-0.34 2.0 PVC 15.69 10 5-15 Surficial - Upper Zone W-83 744975.0629 2024667.4890 6/29/2019 136.22 135.81

-0.41 2.0 PVC 26.46 10 15.5-25.5 Surficial - Upper Zone W-84 745177.2489 2024721.4980 6/30/2019 136.66 135.99

-0.67 2.0 PVC 21.05 10 10-20 Surficial - Upper Zone W-85 745079.7122 2025107.6820 6/11/2019 135.74 138.69 2.95 2.0 PVC 44.77 5

39-44 Surficial - Lower Zone W-86 745082.2852 2025100.8040 6/11/2019 135.68 138.77 3.09 2.0 PVC 35.09 10 24-34 Surficial - Upper Zone W-87 745952.7641 2024385.8120 6/30/2019 136.66 136.39

-0.27 2.0 PVC 33.17 5

27-32 Surficial - Lower Zone W-88 746574.7739 2022883.9580 6/17/2019 140.06 143.10 3.04 2.0 PVC 41.37 5

36-41 Surficial - Lower Zone W-89 746583.3384 2022888.2490 6/13/2019 140.12 142.82 2.70 2.0 PVC 25.46 10 15-25 Surficial - Upper Zone W-90 745981.1215 2022011.5510 6/13/2019 140.23 143.33 3.10 2.0 PVC 39.90 5

35-40 Surficial - Lower Zone W-91 745976.3596 2022016.7650 6/13/2019 139.57 142.81 3.24 2.0 PVC 25.05 10 15-25 Surficial - Upper Zone W-92 744382.4699 2023714.9210 6/12/2019 120.11 123.33 3.22 2.0 PVC 33.67 5

29-34 Surficial - Lower Zone W-93 745162.2579 2024346.8430 9/18/2019 136.87 136.49

-0.38 2.0 PVC 35.38 5

30-35 Surficial - Lower Zone W-94 744728.0254 2021983.5560 9/17/2019 115.28 118.04 2.76 2.0 PVC 29.40 5

24-29 Surficial - Lower Zone W-95 744375.6603 2022553.4620 9/17/2019 113.53 116.40 2.86 2.0 PVC 33.41 5

28-33 Surficial - Lower Zone W-96 743746.7835 2024643.8120 9/17/2019 113.65 116.46 2.81 2.0 PVC 30.03 5

25-30 Surficial - Upper Zone W-97 744244.0503 2024547.7590 9/17/2019 113.92 116.93 3.01 2.0 PVC 18.91 5

13-18 Surficial - Upper Zone Gator SG 744600.5136 2023820.4020 7/16/2019 NS 120.31 N/A N/A N/A N/A N/A N/A N/A Upper SG 744292.2317 2023220.4190 7/16/2019 NS 112.41 N/A N/A N/A N/A N/A N/A N/A Lower SG 743333.8536 2024092.0010 7/16/2019 NS 112.39 N/A N/A N/A N/A N/A N/A N/A Creek SG 743263.2548 2024076.8640 7/16/2019 NS 109.05 N/A N/A N/A N/A N/A N/A N/A Notes:

ft = feet in = inches ft msl = feet above mean sea level ft bgs = feet below ground surface NS - not surveyed N/A - not applicable SG - staff gauge Top of casing and ground surface elevations surveyed by AECOM during November 2018 and November 2019 Horizontal coordinates are referenced to the State Plane Coordinate System and the North American Datum of 1983 (NAD 83).

Vertical locations are referenced to the North American Vertical Datum of 1988 (NAVD 88).

Page 3 of 3

Table 2 Groundwater Levels and Elevations Westinghouse Columbia Fuel Fabrication Facility Hopkins, SC AECOM Project No. 60595649 Well Date Measured Screen Interval (ft bgs)

Ground Surface Elevation (ft)

Top of Casing Elevation (ft)

Depth to Water (ft)

Groundwater Elevation (ft)

WRW-1 10/14/19 22.2-32.2 136.00 136.95 9.64 127.31 04/06/20 7.62 129.33 WRW-2 10/14/19 19-29.2 136.98 139.93 18.62 121.31 04/06/20 17.90 122.03 W-3A 10/14/19 72.5-82.5 117.64 120.08 8.79 111.29 04/06/20 4.90 115.18 W-4 10/14/19 10-12 116.50 116.09 10.38 105.71 04/06/20 3.29 112.80 W-6 10/14/19 23.5-28.5 136.96 136.46 11.22 125.24 04/06/20 9.65 126.81 W-7A 10/14/19 13-18 132.94 135.06 12.35 122.71 04/06/20 10.87 124.19 W-10 10/14/19 18.5-23.5 136.89 136.81 16.50 120.31 04/06/20 14.87 121.94 W-11 10/14/19 25.5-28.5 138.45 140.76 19.02 121.74 04/06/20 17.25 123.51 W-13R 10/14/19 15-20 136.38 136.13 12.96 123.17 04/06/20 10.80 125.33 W-14 10/14/19 23.5-28.5 136.22 137.83 17.62 120.21 04/06/20 15.23 122.60 W-15 10/14/19 13.5-18.5 126.67 127.90 12.90 115.00 04/06/20 11.20 116.70 W-16 10/14/19 15.5-18.5 125.64 124.93 3.71 121.22 04/06/20 1.93 123.00 W-17 10/14/19 23.5-28 137.57 139.27 14.56 124.71 04/06/20 13.59 125.68 W-18R 10/14/19 12.5-17.5 137.15 136.71 12.20 124.51 04/06/20 10.95 125.76 W-19B 10/14/19 30-40.5 140.58 142.85 25.17 117.68 04/06/20 23.90 118.95 W-20 10/14/19 11.5-16.3 113.27 116.16 10.60 105.56 04/06/20 6.92 109.24 W-22 10/14/19 13.4-17.8 137.08 136.51 11.68 124.83 04/06/20 9.90 126.61 W-23R 10/14/19 15.5-20.5 137.45 140.47 19.19 121.28 04/06/20 17.52 122.95 W-24 10/14/19 10.1-15.1 139.83 141.94 11.78 130.16 04/06/20 7.68 134.26 W-25 10/14/19 22.9-27.7 114.98 115.88 10.95 104.93 04/06/20 7.40 108.48 W-26 10/14/19 25.5-30.5 140.59 142.21 26.37 115.84 04/06/20 24.20 118.01 W-27 10/14/19 14.1-18.9 120.22 121.87 11.28 110.59 04/06/20 9.72 112.15 W-28 10/14/19 9.8-14.7 136.98 138.88 12.60 126.28 04/06/20 11.32 127.56 W-29 10/14/19 10-15.1 136.96 138.61 12.41 126.20 04/06/20 11.10 127.51 W-30 10/14/19 10.2-15.2 136.87 138.81 12.65 126.16 04/06/20 11.40 127.41 Page 1 of 4

Table 2 Groundwater Levels and Elevations Westinghouse Columbia Fuel Fabrication Facility Hopkins, SC AECOM Project No. 60595649 Well Date Measured Screen Interval (ft bgs)

Ground Surface Elevation (ft)

Top of Casing Elevation (ft)

Depth to Water (ft)

Groundwater Elevation (ft)

W-32 10/14/19 17-22.5 138.33 140.61 19.59 121.02 04/06/20 18.12 122.49 W-33 10/14/19 15.1-20.7 138.06 139.33 15.85 123.48 04/06/20 14.90 124.43 W-35 10/14/19 16-21 136.59 139.07 11.78 127.29 04/06/20 9.75 129.32 W-36 10/14/19 15-20 134.16 136.29 8.66 127.63 04/06/20 6.25 130.04 W-37 10/14/19 15.5-20.5 136.58 139.04 12.05 126.99 04/06/20 10.25 128.79 W-38 10/14/19 15-20 136.71 136.51 10.45 126.06 04/06/20 9.10 127.41 W-39 10/14/19 12-22 139.08 141.15 16.25 124.90 04/06/20 14.89 126.26 W-40 10/14/19 5-15 136.42 139.26 11.95 127.31 04/06/20 10.00 129.26 W-41R 10/14/19 14-24 131.02 133.81 15.94 117.87 04/06/20 14.97 118.84 W-42 10/14/19 20-30 137.83 140.96 26.32 114.64 04/06/20 24.55 116.41 W-43 10/14/19 10.5-20.5 138.09 141.33 15.65 125.68 04/06/20 13.31 128.02 W-44 10/14/19 16-26 131.93 134.86 18.42 116.44 04/06/20 17.38 117.48 W-45 10/14/19 6-16 137.20 140.02 12.85 127.17 04/06/20 10.92 129.10 W-46 10/14/19 15.5-25.5 132.39 134.74 14.02 120.72 04/06/20 13.49 121.25 W-47 10/14/19 34.3-44.8 140.70 141.90 26.99 114.91 04/06/20 25.01 116.89 W-48 10/14/19 30.7-41.3 139.74 142.56 27.21 115.35 04/06/20 25.25 117.31 W-49 10/14/19 105-115 137.82 140.25 31.07 109.18 04/06/20 27.15 113.10 W-50 10/14/19 114.5-124.5 136.79 139.58 25.27 114.31 04/06/20 21.52 118.06 W-51 10/14/19 10-15 136.67 136.51 9.27 127.24 04/06/20 7.30 129.21 W-52 10/14/19 10-15 136.71 136.19 9.15 127.04 04/06/20 7.20 128.99 W-53 10/14/19 10-15 136.83 136.54 9.42 127.12 04/06/20 7.60 128.94 W-54 10/14/19 10-15 136.79 136.52 9.53 126.99 04/06/20 7.65 128.87 Page 2 of 4

Table 2 Groundwater Levels and Elevations Westinghouse Columbia Fuel Fabrication Facility Hopkins, SC AECOM Project No. 60595649 Well Date Measured Screen Interval (ft bgs)

Ground Surface Elevation (ft)

Top of Casing Elevation (ft)

Depth to Water (ft)

Groundwater Elevation (ft)

W-55 10/14/19 10-15 136.90 136.63 9.72 126.91 04/06/20 7.92 128.71 W-56 10/14/19 10-15 136.83 136.68 9.75 126.93 04/06/20 8.00 128.68 W-57 10/14/19 10-15 136.90 136.73 9.97 126.76 04/06/20 8.50 128.23 W-58 10/14/19 10-15 136.85 136.37 10.63 125.74 04/06/20 9.30 127.07 W-59 10/14/19 10-15 136.10 136.42 10.77 125.65 04/06/20 9.60 126.82 W-60 10/14/19 32-37 137.25 140.20 22.12 118.08 04/06/20 20.77 119.43 W-61 10/14/19 13-23 137.34 140.60 18.96 121.64 04/06/20 16.59 124.01 W-62 10/14/19 19-24 125.63 128.38 13.59 114.79 04/06/20 12.66 115.72 W-63 10/14/19 37-42 138.78 141.02 27.31 113.71 04/06/20 26.00 115.02 W-64 10/14/19 21-31 140.15 142.75 27.25 115.50 04/06/20 25.21 117.54 W-65 10/14/19 26.5-31.5 138.17 140.95 14.07 126.88 04/06/20 12.15 128.80 W-66 10/14/19 12-22 138.01 140.91 13.72 127.19 04/06/20 11.75 129.16 W-67 10/14/19 21-31 132.60 135.26 19.54 115.72 04/06/20 16.57 118.69 W-68 10/14/19 13-18 113.40 116.53 13.53 103.00 04/06/20 5.59 110.94 W-69 10/14/19 7.75-17.75 137.67 140.64 9.75 130.89 04/06/20 7.54 133.10 W-70 10/14/19 44-49 138.02 141.00 14.88 126.12 04/06/20 10.46 130.54 W-71 10/14/19 93-103 137.96 140.72 25.98 114.74 04/06/20 22.27 118.45 W-72 10/14/19 5-15 136.81 136.29 9.24 127.05 04/06/20 7.43 128.86 W-73 10/14/19 5-15 136.85 136.45 9.61 126.84 04/06/20 7.89 128.56 W-74 10/14/19 25-30 136.64 139.93 13.46 126.47 04/06/20 11.88 128.05 W-75 10/14/19 5-15 136.60 139.85 13.06 126.79 04/06/20 11.40 128.45 W-76 10/14/19 5-15 137.04 136.85 9.78 127.07 04/06/20 9.35 127.50 W-77 10/14/19 5-15 136.85 136.53 9.98 126.55 04/06/20 8.47 128.06 W-78 10/14/19 5-15 136.75 136.31 10.05 126.26 04/06/20 8.75 127.56 W-79 10/14/19 5-15 136.49 136.12 9.06 127.06 04/06/20 7.60 128.52 Page 3 of 4

Table 2 Groundwater Levels and Elevations Westinghouse Columbia Fuel Fabrication Facility Hopkins, SC AECOM Project No. 60595649 Well Date Measured Screen Interval (ft bgs)

Ground Surface Elevation (ft)

Top of Casing Elevation (ft)

Depth to Water (ft)

Groundwater Elevation (ft)

W-80 10/14/19 5-15 136.34 135.87 11.08 124.79 04/06/20 9.07 126.80 W-81 10/14/19 5-15 136.81 136.43 12.02 124.41 04/06/20 10.40 126.03 W-82 10/14/19 5-15 136.57 136.23 12.72 123.51 04/06/20 10.83 125.40 W-83 10/14/19 15.5-25.5 136.22 135.81 13.95 121.86 04/06/20 12.04 123.77 W-84 10/14/19 10-20 136.66 135.99 8.45 127.54 04/06/20 5.40 130.59 W-85 10/14/19 39-44 135.74 138.69 22.01 116.68 04/06/20 18.85 119.84 W-86 10/14/19 24-34 135.68 138.77 20.59 118.18 04/06/20 17.76 121.01 W-87 10/14/19 27-32 136.66 136.39 8.93 127.46 04/06/20 6.85 129.54 W-88 10/14/19 36-41 140.06 143.10 23.42 119.68 04/06/20 21.42 121.68 W-89 10/14/19 15-25 140.12 142.82 22.10 120.72 04/06/20 20.04 122.78 W-90 10/14/19 35-40 140.23 143.33 27.38 115.95 04/06/20 25.84 117.49 W-91 10/14/19 15-25 139.57 142.81 27.56 115.25 04/06/20 25.70 117.11 W-92 10/14/19 29-34 120.11 123.33 17.77 105.56 04/06/20 14.28 109.05 W-93 10/14/19 30-35 136.87 136.49 10.42 126.07 04/06/20 8.55 127.94 W-94 10/14/19 24-29 115.28 118.04 12.14 105.90 04/06/20 8.51 109.53 W-95 10/14/19 28-33 113.53 116.40 10.71 105.69 04/06/20 7.03 109.37 W-96 10/14/19 25-30 113.65 116.46 11.08 105.38 04/06/20 7.39 109.07 W-97 10/14/19 13-18 113.92 116.93 7.43 109.50 04/06/20 4.30 112.63 Gator SG 10/14/19 N/A NS 120.31 0.85 117.16 04/06/20 1.46 117.77 Upper SG 10/14/19 N/A NS 112.41 0.60 109.01 04/06/20 1.46 109.87 Lower SG 10/14/19 N/A NS 112.39 0.26 108.65 04/06/20 0.96 109.35 Creek SG 10/14/19 N/A NS 109.05 0.64 105.69 04/06/20 1.20 106.25 Notes ft - feet ft bgs - feet below ground surface SG - staff gauge N/A - not applicable NS - Not Surveyed Page 4 of 4

Table 3 Summary of Groundwater Field Parameter Data Westinghouse Columbia Fuel Fabrication Facility AECOM Project No. 60595649 Well Sample Date Temperature (0C) pH (S.U.)

Conductivity (us/cm)

Dissolved Oxygen (mg/L)

ORP (mv)

Turbidity (NTU)

Color Odor W-RW1 10/03/19 26.7 5.27 82 39.00 253 9.05 clear none 04/15/20 20.6 5.01 82 3.19 269 3.90 clear none W-RW2 10/11/19 21.4 4.77 148 28.10 222 0.41 clear none 04/20/20 17.9 4.68 139 1.65 318 0.74 clear none W-3A 10/10/19 19.2 4.51 25 0.38 238 8.50 clear none 04/27/20 18.3 4.38 21 0.14 242 5.21 clear none W-4 10/10/19 22.2 6.36 293 0.68

-16 9.17 clear none 04/27/20 19.3 6.91 229 2.00 112 0.51 clear none W-6 10/07/19 23.6 6.27 2,000 0.40 186 5.59 clear none 04/07/20 20.6 6.15 1,319 2.40 208 62.68 clear none W-7A 10/09/19 22.0 6.66 2,988 0.38 168 6.72 clear none 04/10/20 17.6 6.77 1,985 0.26 191 4.92 clear none W-10 10/09/19 23.5 5.68 669 0.37 165 3.68 clear none 04/13/20 20.2 5.88 479 0.28 172 5.58 clear none W-11 10/08/19 22.0 5.35 490 0.53 202 8.28 clear none 04/10/20 19.4 5.09 327 0.43 209 5.32 clear none W-13R 10/08/19 25.3 5.97 464 0.20 187 8.13 clear none 04/08/20 21.5 5.80 365 0.23 192 9.48 clear none W-14 10/18/19 21.2 6.12 494 0.38 18 7.49 clear none 04/22/20 19.2 6.15 480 0.70

-46 0.00 clear none W-15 10/21/19 21.4 5.85 453 0.34 208 2.86 clear none 04/21/20 18.9 5.94 406 0.19 216 11.16 clear none W-16 10/21/19 21.9 5.90 331 0.27 102 6.47 clear none 04/21/20 19.9 6.05 258 0.24 116 8.62 clear none W-17 10/21/19 22.3 6.22 259 0.27 173 0.44 clear none 04/20/20 19.4 6.42 344 0.86 192 10.83 clear none W-18R 10/07/19 23.6 7.39 5,490 0.71 136 2.52 clear none 04/07/20 22.0 7.56 3,924 4.60 184 19.02 clear none W-19B 10/21/19 19.2 4.85 72 3.88 279 5.10 clear none 04/17/20 18.8 4.67 61 4.09 315 1.90 clear none W-20 10/15/19 20.7 5.04 126 0.32 219 6.58 clear none 04/27/20 17.0 5.31 91 0.16 169 3.16 clear none W-22 10/07/19 25.7 5.45 1,442 0.37 200 4.57 clear none 04/07/20 20.0 5.40 519 1.90 204 7.38 clear none W-23R 10/18/19 18.5 4.86 49 4.24 310 3.65 clear none 04/21/20 18.1 4.51 51 5.76 317 2.15 clear none W-24 10/11/19 22.6 5.13 36 3.40 31 4.75 clear none 04/22/20 18.5 4.50 44 2.44 200 10.26 clear none W-25 10/15/19 19.0 6.04 171 0.30

-53 36.15 clear none 04/27/20 17.2 6.36 140 0.25

-81 15.61 clear Woodsy W-26 10/14/19 19.5 5.44 233 0.50 229 7.50 clear none 04/16/20 18.3 5.26 140 0.40 260 3.18 clear none W-27 10/10/19 19.6 6.08 351 0.36

-71 6.15 clear none 04/27/20 17.2 6.12 319 0.18

-68 19.90 clear none Page 1 of 5

Table 3 Summary of Groundwater Field Parameter Data Westinghouse Columbia Fuel Fabrication Facility AECOM Project No. 60595649 Well Sample Date Temperature (0C) pH (S.U.)

Conductivity (us/cm)

Dissolved Oxygen (mg/L)

ORP (mv)

Turbidity (NTU)

Color Odor W-28 10/07/19 25.6 5.76 498 5.60 183 4.63 clear none 04/03/20 20.0 6.22 380 4.10 311 3.16 clear none W-29 10/07/19 25.6 7.50 310 2.80 150 2.75 clear none 04/03/20 19.8 6.89 324 2.10 151 0.99 clear none W-30 10/07/19 26.3 6.16 839 4.70 178 4.16 clear none 04/13/20 21.0 6.09 1,178 4.55 176 6.01 clear none W-32 10/08/19 22.0 6.64 1,741 0.50 172 4.14 clear none 04/10/20 18.8 6.74 1,022 0.29 186 2.72 clear none W-33 10/17/19 20.6 5.21 121 14.90 221 1.30 clear none 04/16/20 18.0 5.04 120 1.05 255 1.52 clear none W-35 10/02/19 24.0 5.40 191 2.32 205 2.43 clear none 04/21/20 19.1 5.46 107 3.89 241 6.11 clear none W-36 10/02/19 25.8 5.42 35 3.90 175 7.92 clear none 04/20/20 18.1 5.36 30 0.24 159 4.80 clear none W-37 10/02/19 25.5 5.38 194 2.80 205 2.24 clear none 04/08/20 21.5 5.21 126 3.48 228 3.15 clear none W-38 10/04/19 26.1 4.84 216 3.17 271 4.32 clear none 04/03/20 23.0 4.86 145 2.61 280 1.54 clear none W-39 10/18/19 23.5 5.15 482 26.00 253 0.40 clear none 04/24/20 20.6 5.32 451 2.35 225 13.39 clear none W-40 10/15/19 25.3 6.24 79 18.70 157 5.28 clear none 04/16/20 19.9 6.31 69 7.69 165 17.43 clear none W-41R 10/14/19 21.9 5.19 407 3.16 231 0.27 clear none 04/17/20 18.5 5.43 418 6.13 256 0.61 clear none W-42 10/22/19 21.2 4.59 84 0.30 327 5.40 clear none 04/23/20 18.2 4.63 51 1.27 303 3.46 clear none W-43 10/18/19 21.8 4.87 66 31.90 240 0.92 clear none 04/23/20 18.0 5.07 73 3.98 247 12.52 clear none W-44 10/14/19 19.9 4.98 58 3.51 244 0.22 clear none 04/16/20 16.6 5.13 71 4.37 232 9.89 clear none W-45 10/02/19 25.5 6.11 2,623 1.02

-24 9.15 clear none 04/15/20 18.3 6.24 141 0.23

-97 12.02 clear none W-46 10/21/19 20.7 5.38 172 0.39 194 3.96 clear none 04/22/20 17.6 5.39 165 1.89 386 0.92 clear none W-47 10/17/19 19.1 5.72 520 0.52 225 7.79 clear none 04/20/20 18.7 5.66 501 0.43 213 1.63 clear none W-48 10/21/19 19.8 5.19 71 2.41 234 0.94 clear none 04/21/20 18.7 4.90 97 3.34 263 2.11 clear none W-49 10/24/19 20.3 4.88 20 2.44 172 12.70 clear none 04/23/20 18.3 4.75 28 0.56 181 18.49 clear none W-50 10/15/19 22.3 4.71 18 13.50 29 16.60 clear none 04/16/20 20.6 4.84 23 0.30 16 16.43 Cloudy none W-51 10/03/19 26.7 6.17 254 0.26

-113 5.24 clear none 04/09/20 20.2 6.35 220 0.12

-126 12.86 clear none Page 2 of 5

Table 3 Summary of Groundwater Field Parameter Data Westinghouse Columbia Fuel Fabrication Facility AECOM Project No. 60595649 Well Sample Date Temperature (0C) pH (S.U.)

Conductivity (us/cm)

Dissolved Oxygen (mg/L)

ORP (mv)

Turbidity (NTU)

Color Odor W-52 10/03/19 27.1 5.72 247 0.52 41 4.61 clear none 04/09/20 20.1 5.53 175 1.26 114 3.96 clear none W-53 10/03/19 27.9 6.08 180 3.50 53 6.19 clear none 04/09/20 20.1 5.51 140 0.17 70 8.15 clear none W-54 10/04/19 27.8 5.96 126 36.50 122 17.78 clear none 04/09/20 20.4 5.42 123 2.22 236 4.40 clear none W-55 10/04/19 26.0 5.40 160 3.02 202 4.86 clear none 04/08/20 20.8 5.13 120 3.23 225 3.66 clear none W-56 10/04/19 27.4 5.66 131 44.50 241 2.14 clear none 04/07/20 21.1 5.36 126 1.73 235 4.21 clear none W-57 10/03/19 28.8 5.15 166 2.23 205 3.16 clear none 04/07/20 21.2 5.54 136 1.16 224 2.66 clear none W-58 10/04/19 27.8 6.52 406 0.29 159 5.16 clear none 04/07/20 20.6 6.51 248 0.56 181 1.31 clear none W-59 10/05/19 28.0 6.49 318 3.80 181 3.28 clear none 04/07/20 176.7 6.48 409 0.18 177 1.86 clear none W-60 10/17/19 17.7 5.62 93 0.49 80 8.46 clear none 04/10/20 18.1 5.16 95 0.51 102 19.21 clear none W-61 10/17/19 18.8 5.18 97 1.26 219 8.68 clear none 04/10/20 17.6 5.47 119 2.92 112 14.56 cloudy none W-62 10/22/19 18.7 4.98 84 2.73 272 3.25 clear none 04/20/20 17.6 5.40 67 3.16 244 4.90 clear none W-63 10/21/19 21.0 6.88 250 0.52

-68 3.06 clear none 04/21/20 19.4 6.81 319 0.63

-83 12.61 clear none W-64 10/17/19 19.8 5.54 499 0.42 242 2.76 clear none 04/20/20 18.6 5.63 458 0.39 208 1.30 clear none W-65 10/17/19 21.1 6.27 99 38.20

-84 3.18 clear none 04/24/20 19.1 5.85 91 0.24 31 15.80 Clear none W-66 10/17/19 21.7 5.29 55 9.00 235 1.48 clear none 04/24/20 18.0 5.26 57 0.56 180 3.74 clear none W-67 10/18/19 18.0 5.47 200 0.46 219 3.52 clear none 04/21/20 18.5 5.03 189 0.30 280 1.96 clear none W-68 10/22/19 20.5 5.07 50 57.20 232 1.51 clear none 04/20/20 17.4 4.95 70 5.33 271 3.04 clear none W-69 10/23/19 21.4 5.42 85 0.43 84 7.40 clear none 04/16/20 18.0 5.33 57 0.21 108 16.32 clear none W-70 10/23/19 20.7 4.55 53 3.94 312 8.68 cloudy none 04/16/20 19.8 4.66 45 4.63 302 12.29 clear none W-71 10/23/19 21.1 5.71 86 0.31 18 9.12 clear none 04/16/20 20.3 4.79 35 0.33 136 6.64 clear none W-72 10/04/19 24.3 5.72 182 1.24 71 8.62 clear none 04/03/20 19.9 6.22 324 3.18 198 9.45 clear none W-73 10/04/19 27.0 5.70 108 20.20 180 11.55 clear none 04/03/20 20.4 5.36 115 0.45 205 4.67 clear none Page 3 of 5

Table 3 Summary of Groundwater Field Parameter Data Westinghouse Columbia Fuel Fabrication Facility AECOM Project No. 60595649 Well Sample Date Temperature (0C) pH (S.U.)

Conductivity (us/cm)

Dissolved Oxygen (mg/L)

ORP (mv)

Turbidity (NTU)

Color Odor W-74 10/09/19 22.7 5.37 118 0.81 197 3.49 clear none 04/08/20 21.8 5.12 118 1.31 251 1.60 clear none W-75 10/09/19 25.2 5.85 161 0.40 21 6.66 clear none 04/08/20 20.9 5.25 136 0.21 156 6.47 clear none W-76 10/05/19 27.2 5.21 119 32.90 344 1.14 clear none 04/14/20 23.1 4.54 126 3.42 330 6.14 clear none W-77 10/06/19 27.5 8.77 977 4.50 73 23.15 clear none 04/14/20 21.6 7.59 1,959 0.21 170 1.84 clear none W-78 10/05/19 25.4 6.24 180 46.00 198 2.45 clear none 04/14/20 20.3 6.03 210 2.95 193 1.23 clear none W-79 10/07/19 27.5 5.50 165 3.92 188 7.96 clear none 04/13/20 22.5 6.33 191 7.79 195 2.67 clear none W-80 10/06/19 26.2 4.83 261 11.50 253 8.92 clear none 04/14/20 20.5 4.91 232 2.79 292 9.33 clear none W-81 10/08/19 23.7 5.56 145 0.54 64 7.02 clear none 04/14/20 21.0 8.65 81 0.23 149 5.75 clear none W-82 10/08/19 23.9 5.08 157 1.43 126 20.52 clear none 04/14/20 19.3 5.43 81 2.34 220 12.09 clear none W-83 10/08/19 23.7 5.40 144 1.37 178 8.61 clear none 04/13/20 22.5 5.64 145 1.43 152 3.56 clear none W-84 10/08/19 26.9 5.68 127 0.52 116 6.79 clear none 04/13/20 21.9 5.43 156 0.25 76 6.45 clear none W-85 10/23/19 20.6 5.93 276 0.34

-40 5.65 clear none 04/28/20 19.4 6.10 224 0.29

-49 3.35 clear none W-86 10/23/19 21.1 5.91 230 0.31 27 10.00 clear none 04/28/20 20.8 5.57 186 0.60 115 18.59 clear none W-87 10/02/19 24.0 6.21 216 0.59

-31 45.14 clear none 04/15/20 20.8 6.18 125 0.15

-18 17.96 clear none W-88 10/22/19 19.5 5.20 52 67.10 229 1.02 clear none 04/17/20 17.5 5.45 60 5.67 282 3.21 clear none W-89 10/22/19 19.9 4.92 41 71.40 253 2.01 clear none 04/17/20 18.0 5.03 54 6.02 301 2.95 clear none W-90 10/22/19 19.8 4.82 74 4.78 282 8.76 clear none 04/17/20 19.4 5.12 53 4.76 246 10.08 clear none W-91 10/22/19 NS NS NS NS NS NS NS NS 04/22/20 19.5 5.06 67 4.17 219 3.59 clear none W-92 10/10/19 18.4 5.78 208 0.60 23 7.33 clear none 04/27/20 17.8 5.82 188 0.20

-16 1.62 clear none W-93 10/06/19 24.9 5.39 90 19.20 240 35.58 clear none 04/14/20 22.0 5.41 107 1.84 220 1.05 clear none W-94 10/15/19 17.6 5.94 138 0.42

-19 8.34 clear none 04/24/20 17.4 5.67 122 0.13 14 3.26 clear none W-95 10/15/19 18.3 5.97 193 0.36

-36 8.37 clear none 04/24/20 17.1 6.01 190 0.17

-63 12.27 clear none Page 4 of 5

Table 3 Summary of Groundwater Field Parameter Data Westinghouse Columbia Fuel Fabrication Facility AECOM Project No. 60595649 Well Sample Date Temperature (0C) pH (S.U.)

Conductivity (us/cm)

Dissolved Oxygen (mg/L)

ORP (mv)

Turbidity (NTU)

Color Odor W-96 10/11/19 20.1 5.99 257 0.27 3

13.06 clear none 04/24/20 18.8 5.65 238 0.13

-8 15.56 cloudy none W-97 10/11/19 19.2 5.68 206 0.48 125 8.75 clear none 04/24/20 16.6 5.13 184 0.13 191 4.31 clear none Notes:

0C - degrees celcius S.U. - standard units us/cm - microSiemens per centimeter mg/L - milligrams per liter ORP - Oxidation Reduction Potential mv - millivolts NTU - nephelometric turbidity units NS - not sampled Page 5 of 5

Table 4 Summary of Groundwater Analytical Results Westinghouse Columbia Fuel Fabrication Facility Hopkins, South Carolina AECOM Project No. 60595649 Carbon Disulfide ug/L Chloroform ug/L cis-1,2-Dichloroethene ug/L Ethylbenzene ug/L Tetrachloroethene ug/L Trichloroethene ug/L Vinyl Chloride ug/L 1,1'-Biphenyl ug/L 2-Methylnaphthalene ug/L Acenaphthene ug/L Carbazole ug/L Fluorene ug/L Naphthalene ug/L Phenanthrene ug/L Fluoride mg/L Ammonia NH3(N) mg/L Nitrate NO3 mg/L Gross Alpha pCi/L Isotopic Uranium 233/234 pCi/L Isotopic Uranium 235/236 pCi/L Isotopic Uranium 238 (HASL300) pCi/L Isotopic Uranium 234 ug/L Isotopic Uranium 235 ug/L Isotopic Uranium 238 ug/L Total Uranium ug/L Gross Beta pCi/L Tc-99 pCi/L Tritium pCi/L 70 700 5

5 2

4 10 15

• 30 50

• 900 Well Date W-RW1 10/03/19

< 1.0

< 1.0

< 1.0

< 1.0 1.4

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.055 0.0129 2.1 2.51 U 0.126 U 0.139 U 0.169 U

< 0.050

< 0.070 0.0815 J 0.0815 J 3.98 1.40 U NA 04/15/20

< 1.0

< 1.0

< 1.0

< 1.0 1.7

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.06 0.0196 2.0 1.01 U 0.195 U 0.0329 U

-0.00701 U

< 0.0500

< 0.0700

< 0.200

< 0.200 1.65 U 0.209 U NA W-RW2 10/11/19

< 1.0

< 1.0

< 1.0

< 1.0 140 8.3

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 NA NA 20 2.00 U 0.252 U 0.107 U 0.0958 U

< 0.050

< 0.070 0.0743 J 0.0743 J 11.9 23.1 U 270 U 04/20/20

< 1.0

< 1.0

< 1.0

< 1.0 140 11

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.089 0.0204 12 3.17 U 0.00526 U

-0.00930 U 0.0482 U

< 0.0500

< 0.0700

< 0.200

< 0.200 3.53 U 3.26 U 79.8 U W-3A 10/10/19

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.015 0.0256

< 0.020 2.36 U 0.287 U 0.0414 U 0.145 U

< 0.050

< 0.070

< 0.200

< 0.200 1.15 U 7.25 U NA 04/27/20

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80

< 0.10 0.0146

< 0.020 3.56 U 0.0204 U 0 U 0.0308 U

< 0.0500

< 0.0700 0.106 J 0.106 J 2.21 U

-0.726 U NA W-4 10/11/19

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 4.86 0.404 0.023 3.36 U 0.313 0.124 U 0.392

< 0.050

< 0.070 0.146 J 0.146 J 19.4 41.3 NA 04/27/20

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 4.89 0.0225 1.4

-0.539 U 0.112 U

-0.000240 U 0.116 U

< 0.0500

< 0.0700 0.181 J 0.181 J 20.9 24.5 NA W-6 10/07/19

< 1.0

< 1.0 2.8

< 1.0 16 2.5

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.126 134 210 9.09 0.372 0.0443 U 0.153 U

< 0.050

< 0.070 0.232 0.232 1370 2440 NA 04/07/20

< 1.0

< 1.0 2.7

< 1.0 19 2.7

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.112 58 190 37.6 0.0213 U 0 U 0.0977 U

< 0.0500

< 0.0700 0.183 J 0.183 J 1260 2450 NA W-7A 10/09/19

< 1.0

< 1.0

< 1.0

< 1.0 1.9

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 6.47 48.5 390 6.35 0.409 0.0909 U 0.259

< 0.050

< 0.070 0.698 0.698 114 210

-16.9 U 04/10/20

< 1.0

< 1.0

< 1.0

< 1.0 1.6

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 6.04 44.6 330 1.99 U 0.240

-0.0195 U 0.219

< 0.0500

< 0.0700 0.716 0.716 54.0 180 115 U W-10 10/09/19

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 3.32 6.46 37 3.19 0.0993 U 0.0935 U 0.180 U

< 0.050

< 0.070 0.083 J 0.083 J 81.3 118 32.7 U 04/13/20

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 2.95 4.24 21

-0.113 U 0.0637 U 0.00902 U 0.0301 U

< 0.0500

< 0.0700

< 0.200

< 0.200 47.8 81.2 145 U W-11 10/08/19

< 1.0 1.1

< 1.0

< 1.0 1.4

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.021 4.09 56 7.82 0.205 U 0.0769 U 0.133 U

< 0.050

< 0.070

< 0.200

< 0.200 2450 3420 NA 04/10/20

< 1.0 1

< 1.0

< 1.0 1.4

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.017 4.95 51 36.3

-0.0539 U 0.0116 U 0.00916 U

< 0.0500

< 0.0700

< 0.200

< 0.200 2080 3440 NA W-13R 10/08/19

< 1.0

< 1.0

< 1.0

< 1.0 15 1.4

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 8.11 31.5 18 2.15 U 0.246 U 0.0418 U 0.221

< 0.050

< 0.070 0.139 J 0.139 J 53.2 63.4 116 U 04/08/20

< 1.0

< 1.0

< 1.0

< 1.0 14 1.3

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 7.07 21.4 13 3.48 U 0.0454 U

-0.000219 U 0.0527 U

< 0.0500

< 0.0700 0.076 J 0.076 J 36.0 58.9

-95.1 U W-14 10/18/19

< 1.0

< 1.0

< 1.0

< 1.0 1.1

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.079 4.26 0.061 4.27 0.0696 U

-0.0412 U 0.139 U

< 0.050

< 0.070 0.368 0.368 35.6

-4.64 U NA 04/22/20

< 1.0

< 1.0

< 1.0

< 1.0 4.8 1.3

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.083 4.27 0.11 4.99 0.532 0.110 U 0.467

< 0.0500

< 0.0700 0.36 0.36 15.4 0.611 U NA W-15 10/21/19

< 1.0

< 1.0 1.3

< 1.0 12 2.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 1.88 12.6 35

-0.242 U 0.0108 U 0.162 U 0.0531 U

< 0.050

< 0.070

< 0.200

< 0.200 174 253

-19.1 U 04/21/20

< 1.0

< 1.0

< 1.0

< 1.0 7.2 1.4

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 2.28 14.7 36 8.12

-0.000428 U

-0.0236 U

-0.00796 U

< 0.0500

< 0.0700

< 0.200

< 0.200 114 219 50.2 U W-16 10/21/19

< 1.0

< 1.0 1.5

< 1.0 7.8 2.2

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 9.5 13.3 3.2 0.421 U 0.168 U 0.0107 U 0.0718 U

< 0.050

< 0.070

< 0.200

< 0.200 10.6

-4.45 U 12.8 U 04/21/20

< 1.0

< 1.0 1.3

< 1.0 5.6 1.7

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 8.92 16.0 2.5 1.86 U 0.0631 U

-0.0225 U

-0.0546 U

< 0.0500

< 0.0700 0.0827 J 0.0827 J 14.4 6.84

-117 U W-17 10/21/19

< 1.0

< 1.0

< 1.0

< 1.0 4.3

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 2.22 5.79 16 2.86 U 0.209 U 0.0726 U 0.0507 U

< 0.050

< 0.070 0.0855 J 0.0855 J 538 820 NA 04/20/20

< 1.0

< 1.0

< 1.0

< 1.0 2

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 2.55 8.97 13 15.5 0.249 U 0 U

-0.0261 U

< 0.0500

< 0.0700 0.121 J 0.121 J 210 429 NA W-18R 10/07/19

< 1.0 1.9

< 1.0

< 1.0 3.5

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 6.34 126 770 9.79 U 1.53 0.266 1.17

< 0.050 0.035 J 4.06 4.1 150 214 210 U 04/07/20

< 1.0 1.4

< 1.0

< 1.0 3.4

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 4.60 55.0 790 8.00 U 2.12 0.0757 U 1.41

< 0.0500 0.05 J 4.32 4.37 73.6 295

-11.8 U W-19B 10/21/19

< 1.0

< 1.0

< 1.0

< 1.0 150 2.5

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.019 0.0146 3.8 2.26 U 0.197 U 0.125 U 0.0559 U

< 0.050

< 0.070

< 0.200

< 0.200

-0.0894 U

-3.26 U NA 04/17/20

< 1.0

< 1.0

< 1.0

< 1.0 130 2.3

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.01 0.0168 4.2 1.20 U

-0.165 U 0.0238 U

-0.133 U

< 0.0500

< 0.0700

< 0.200

< 0.200 4.24 U

-1.67 U NA W-20 10/15/19

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.077 0.0632

< 0.020 0.912 U 0.0228 U 0.0276 U 0.0995 U

< 0.050

< 0.070

< 0.200

< 0.200 3.22 U

-5.36 U NA 04/27/20

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.03 0.0266 0.045 1.35 U

-0.0101 U 0.00993 U 0.0323 U

< 0.0500

< 0.0700

< 0.200

< 0.200 3.53 U

-0.189 U NA W-22 10/07/19

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 5.52 61.8 100 2.92 U 0.905 0.136 U 0.322

< 0.050 0.0177 J 0.854 0.872 29.6 57.4 115 U 04/07/20

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 3.63 160 50 3.52 0.420 0.0932 U 0.124 U

< 0.0500 0.0108 J 0.599 0.61 14.9 20.1 62.4 U W-23R 10/18/19

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.017 0.0154 0.71

-0.743 U 0.0833 U

-0.0126 U 0.0221 U

< 0.050

< 0.070

< 0.200

< 0.200 1.68 U

-5.85 U NA 04/21/20

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.022 0.0292 0.88 0.307 U

-0.0211 U 0.0770 U 0.0184 U

< 0.0500

< 0.0700

< 0.200

< 0.200 2.18 U

-0.809 U NA W-24 10/11/19

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.025 0.0283

< 0.020

-0.396 U 0.136 U 0.0816 U 0.0660 U

< 0.050

< 0.070

< 0.200

< 0.200 2.51 U 13.0 U 67.8 U 04/22/20

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.024 0.0313

< 0.020 0.684 U 0.0281 U 0.0190 U

-0.00815 U

< 0.0500

< 0.0700

< 0.200

< 0.200 4.54 0.432 U

-183 U W-25 10/16/19

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.126 1.91 0.067 10.1 0.195 U 0.0748 U 0.269

< 0.050

< 0.070 0.295 0.295 7.27

-30.7 U NA 04/27/20

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.106 0.715

< 0.020 0.271 U

-0.0246 U

-0.0124 U

-0.0306 U

< 0.0500

< 0.0700 0.0841 J 0.0841 J 2.82 U

-1.90 U NA W-26 10/14/19

< 1.0

< 1.0 3.7

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 1.42 1.75 3.2 0.697 U 0.0497 U 0.0344 U 0.0381 U

< 0.050

< 0.070

< 0.200

< 0.200 12.5

-19.6 U 38.6 U 04/16/20

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 1.53 1.54 2.5 0.249 U 0.0815 U

-0.0104 U 0.0450 U

< 0.0500

< 0.0700

< 0.200

< 0.200 9.39 6.84

-29.4 U W-27 10/10/19

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 3.97 6.29

< 0.020

-0.689 U 0.0588 U 0.198 0.171 U

< 0.050

< 0.070

< 0.200

< 0.200 5.10 2.42 U NA 04/27/20

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 4.02 6.81 0.076 3.64 U 0.00249 U 0.0456 U

-0.0652 U

< 0.0500

< 0.0700

< 0.200

< 0.200 10.9 3.23 U NA Radionuclides Inorganics MCL/Action Level VOCs SVOCs Page 1 of 5

Table 4 Summary of Groundwater Analytical Results Westinghouse Columbia Fuel Fabrication Facility Hopkins, South Carolina AECOM Project No. 60595649 Carbon Disulfide ug/L Chloroform ug/L cis-1,2-Dichloroethene ug/L Ethylbenzene ug/L Tetrachloroethene ug/L Trichloroethene ug/L Vinyl Chloride ug/L 1,1'-Biphenyl ug/L 2-Methylnaphthalene ug/L Acenaphthene ug/L Carbazole ug/L Fluorene ug/L Naphthalene ug/L Phenanthrene ug/L Fluoride mg/L Ammonia NH3(N) mg/L Nitrate NO3 mg/L Gross Alpha pCi/L Isotopic Uranium 233/234 pCi/L Isotopic Uranium 235/236 pCi/L Isotopic Uranium 238 (HASL300) pCi/L Isotopic Uranium 234 ug/L Isotopic Uranium 235 ug/L Isotopic Uranium 238 ug/L Total Uranium ug/L Gross Beta pCi/L Tc-99 pCi/L Tritium pCi/L 70 700 5

5 2

4 10 15

• 30 50

• 900 Well Date Radionuclides Inorganics MCL/Action Level VOCs SVOCs W-28 10/07/19

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 5.45 0.884 6.3 3.14 U 0.672 0 U 0.119 U

< 0.050

< 0.070 0.429 0.429 8.26 20.1 U NA 02/04/20

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 NA NA 8.0 NA NA NA NA NA NA NA NA NA NA NA 02/04/20

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 6.55 0.032 8.0

< 5.00 0.828

< 0.500

< 0.500

< 0.0500 0.0101 J 0.546 0.556 6.09

< 5.00 NA 04/03/20

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 5.43 0.0355 7.0 1.78 U 0.665

-0.0112 U 0.0287 U

< 0.0500 0.0136 J 0.696 0.71 3.86

-0.551 U NA 07/13/20

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 0.8

< 0.16

< 0.16

< 0.8

< 0.16

< 0.16

< 0.16 NA NA 6.6 1.96 U 0.680

-0.0121 U 0.0846 U

< 0.0500 0.017 J 0.877 0.894 6.29

-2.76 U NA W-29 10/07/19

< 1.0 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 4.8 22.4 11 2.25 U 1.20 0 U 0.972

< 0.050 0.026 J 2.03 2.05 7.67 11.6 U 116 U 04/03/20

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 3.77 13.2 17 0.844 U 0.0704 U 0.0220 U 0.129 U

< 0.0500 0.0167 J 1.36 1.38 8.48 8.62

-38.7 U W-30 10/07/19

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 8.06 1.83 120 7.57 11.5 0.914 3.31

< 0.050 0.199 8.71 8.91 20.8 49.7 443 U 04/13/20

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 7.98 0.932 120 14.2 8.43 0.236 2.55

< 0.0500 0.173 6.91 7.08 33.9 48.4

-133 U W-32 10/08/19

< 1.0

< 1.0

< 1.0

< 1.0 1.4

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 3.66 47.9 170 7.17 0.322

-0.00982 U 0.191

< 0.050

< 0.070 0.224 0.224 175 321 81.8 U 04/10/20

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 3.50 34.2 140 3.47

-0.0634 U

-0.0231 U

-0.0103 U

< 0.0500

< 0.0700 0.154 J 0.154 J 106 270

-54.0 U W-33 10/17/19

< 1.0

< 1.0 1.0

< 1.0 300 38

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.152 0.0134 13 2.89 U 0.102 U 0.0445 U 0.0274 U

< 0.050

< 0.070

< 0.200

< 0.200 7.78

-24.7 U

-44.2 U 04/16/20

< 5.0

< 5.0

< 5.0

< 5.0 270 33

< 5.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.146 0.0194 8.2 2.26 U

-0.0495 U 0.0619 U 0.206 U

< 0.0500

< 0.0700

< 0.200

< 0.200 5.00 2.90 U 65.3 U W-35 10/02/19

< 1.0

< 1.0

< 1.0

< 1.0 2.6

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.025 0.0075 3.2 0.793 U 0.304 0.0450 U 0.109

< 0.050

< 0.070

< 0.200

< 0.200 3.54 U 21.7 U NA 04/21/20

< 1.0

< 1.0

< 1.0

< 1.0 2.5

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.022 0.0186 3.3 0.263 U 0.123 U 0.0570 U 0.00288 U

< 0.0500

< 0.0700

< 0.200

< 0.200 2.32 U

-0.918 U NA W-36 10/02/19

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.007 0.0089 0.11 0.270 U 0.148 U

-0.0134 U

-0.0108 U

< 0.050

< 0.070

< 0.200

< 0.200

-0.343 U 15.0 U NA 04/20/20

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.014 0.0250 0.056 0.779 U

-0.0208 U 0 U

-0.0293 U

< 0.0500

< 0.0700

< 0.200

< 0.200 4.21

-1.03 U NA W-37 10/02/19

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.02 0.0088 3.5 1.75 U 0.103 U

-0.0108 U 0.0277 U

< 0.050

< 0.070 0.0936 J 0.0936 J

-0.310 U

-14.9 U NA 04/08/20

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.029 0.0100 2.0 0.361 U

-0.00250 U

-0.0274 U

-0.0770 U

< 0.0500

< 0.0700

< 0.200

< 0.200 0.819 U 1.37 U NA W-38 10/04/19

< 1.0

< 1.0

< 1.0

< 1.0 1.8 11

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.176 0.0141 4.3 2.54 U 0.106 U 0 U 0.128

< 0.050

< 0.070 0.183 J 0.183 J 2.43 U

-1.12 U NA 04/03/20

< 1.0

< 1.0

< 1.0

< 1.0 1.4 5.7

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.191 0.0275 3.1 0.335 U 0.105 U 0.0394 U 0.0638 U

< 0.0500

< 0.0700 0.092 J 0.092 J 0.977 U

-0.322 U NA W-39 10/18/19

< 5.0

< 5.0 13

< 5.0 290 5.2

< 5.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.024 0.0218 73 1.22 U

-0.0592 U 0.00196 U 0.149 U

< 0.050

< 0.070

< 0.200

< 0.200 8.84 0.726 U 174 U 04/24/20

< 1.0

< 1.0 18

< 1.0 390 7.6

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.021 0.0182 72 6.68

-0.0345 U 0.0199 U

-0.000162 U < 0.0500

< 0.0700

< 0.200

< 0.200 5.51 7.39 23.7 U W-40 10/15/19

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.166 0.0203 4.3 0.796 U 0.0131 U 0.0454 U 0.129 U

< 0.050

< 0.070

< 0.200

< 0.200 3.44 U

-9.52 U NA 04/16/20

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.139 0.0158 2.4 1.22 U 0.154 U 0.0534 U 0.104 U

< 0.0500

< 0.0700

< 0.200

< 0.200 4.19

-1.41 U NA W-41R 10/14/19

< 1.0

< 1.0 4.4

< 1.0 190 14

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.03 0.0299 65 8.93 0.0652 U 0.0336 U 0.0757 U

< 0.050

< 0.070

< 0.200

< 0.200 14.3

-3.57 U 223 U 04/17/20

< 1.0

< 1.0 3.8

< 1.0 180 4

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.007 0.0181 48

-0.359 U 0.119 U

-0.0106 U

-0.0257 U

< 0.0500

< 0.0700

< 0.200

< 0.200 2.44 U 12.1 49.0 U W-42 10/22/19

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 1.99 0.806 4.7 0.753 U

-0.00113 U 0.110 U 0.0468 U

< 0.050

< 0.070

< 0.200

< 0.200 3.16 U 5.77 U NA 04/23/20

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 1.60 0.197 2.9 0.456 U

-0.0703 U

-0.0113 U

-0.000541 U < 0.0500

< 0.0700

< 0.200

< 0.200 3.17 2.64 U NA W-43 10/18/19

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.111 0.0198 6.3 0.159 U

-0.0235 U 0.0698 U 0.0475 U

< 0.050

< 0.070

< 0.200

< 0.200 3.16 U

-15.7 U 4.14 U 04/23/20

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.018 0.0353 7.1 1.41 U

-0.0261 U

-0.000217 U 0.0525 U

< 0.0500

< 0.0700

< 0.200

< 0.200 2.36 U 1.60 U

-181 U W-44 10/14/19

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.023 0.0186 2.4 3.47 U 0.0335 U 0.0360 U 0.0107 U

< 0.050

< 0.070

< 0.200

< 0.200 0.283 U

-3.15 U

-61.7 U 04/16/20

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80

< 0.10 0.0134 1.7 0.183 U 0.0364 U 0.0426 U 0.0786 U

< 0.0500

< 0.0700

< 0.200

< 0.200 13.3

-0.752 U 44.8 U W-45 10/02/19

< 1.0

< 1.0

< 1.0 2.3

< 1.0

< 1.0

< 1.0 4.2 12 1.5

< 4.0 1.7 15 1.1 0.633 2.08 0.093 4.37 0.897

-0.0125 U 0.477

< 0.050 0.0216 J 0.983 1

16.6 4.99 U NA 04/15/20

< 1.0

< 1.0

< 1.0 3.4

< 1.0

< 1.0

< 1.0

< 4.0 6

1

< 4.0 1

13

< 0.80 0.610 1.26 0.11 3.46 U 0.0405 U

-0.0108 U 0.0729 U

< 0.0500

< 0.0700

< 0.200

< 0.200 49.5 71.1 NA W-46 10/21/19

< 1.0

< 1.0

< 1.0

< 1.0 2.5

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.033 0.0129 7.8 0.656 U 0.317 U

-0.103 U 0.0325 U

< 0.050

< 0.070

< 0.200

< 0.200 40.4 62.8 NA 04/22/20

< 1.0

< 1.0

< 1.0

< 1.0 2.2

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.028 0.200 8.7 1.97 U

-0.0421 U 0.0467 U 0.0605 U

< 0.0500

< 0.0700

< 0.200

< 0.200 34.4 55.6 NA W-47 10/17/19

< 1.0

< 1.0

< 1.0

< 1.0 1.6

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 4.45 16.5 42 1.60 U

-0.0328 U

-0.00816 U

-0.0330 U

< 0.050

< 0.070

< 0.200

< 0.200 61.6 94.2 137 U 04/20/20

< 1.0

< 1.0

< 1.0

< 1.0 1.6

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 3.92 16.8 44 1.26 U

-0.0324 U 0.0453 U 0.0103 U

< 0.0500

< 0.0700 0.102 J 0.102 J 56.7 86.8 273 U W-48 10/21/19

< 1.0

< 1.0 2.1

< 1.0 200 4.9

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.330 0.0446 5.3 0.460 U 0.0449 U 0.106 U 0.0109 U

< 0.050

< 0.070

< 0.200

< 0.200 9.32 13.1 U 87.4 U 04/21/20

< 1.0

< 1.0

< 1.0

< 1.0 1

1.2

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.360 0.0347 5.1

-1.16 U 0.00192 U

-0.0102 U 0.00138 U

< 0.0500

< 0.0700

< 0.200

< 0.200 7.20 13.8

-23.7 U W-49 10/24/19

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.003 0.0151

< 0.020 0.196 U 0.154 U 0.0321 U 0.0380 U

< 0.050

< 0.070 0.0695 J 0.0695 J 4.34 U

-2.03 U NA 04/23/20

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.011 0.0229

< 0.020 5.78

-0.0345 U

-0.000261 U 0.0102 U

< 0.0500

< 0.0700 0.0735 J 0.0735 J 6.76

-0.475 U NA W-50 10/15/19

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.035 0.0185

< 0.020 3.48 U 0.279 U 0.0468 U 0.201 U

< 0.050

< 0.070 0.101 J 0.101 J 0.0720 U

-11.1 U NA 04/16/20

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80

< 0.10 0.0171

< 0.020 1.63 U 0.314 U 0.0999 U 0.133 U

< 0.0500

< 0.0700 0.151 J 0.151 J 3.92

-0.473 U NA Page 2 of 5

Table 4 Summary of Groundwater Analytical Results Westinghouse Columbia Fuel Fabrication Facility Hopkins, South Carolina AECOM Project No. 60595649 Carbon Disulfide ug/L Chloroform ug/L cis-1,2-Dichloroethene ug/L Ethylbenzene ug/L Tetrachloroethene ug/L Trichloroethene ug/L Vinyl Chloride ug/L 1,1'-Biphenyl ug/L 2-Methylnaphthalene ug/L Acenaphthene ug/L Carbazole ug/L Fluorene ug/L Naphthalene ug/L Phenanthrene ug/L Fluoride mg/L Ammonia NH3(N) mg/L Nitrate NO3 mg/L Gross Alpha pCi/L Isotopic Uranium 233/234 pCi/L Isotopic Uranium 235/236 pCi/L Isotopic Uranium 238 (HASL300) pCi/L Isotopic Uranium 234 ug/L Isotopic Uranium 235 ug/L Isotopic Uranium 238 ug/L Total Uranium ug/L Gross Beta pCi/L Tc-99 pCi/L Tritium pCi/L 70 700 5

5 2

4 10 15

• 30 50

• 900 Well Date Radionuclides Inorganics MCL/Action Level VOCs SVOCs W-51 10/03/19

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0 7.4

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.215 0.256 0.11 0.544 U 0.0146 U 0.0799 U

-0.0705 U

< 0.050

< 0.070

< 0.200

< 0.200 3.56

-16.3 U NA 04/09/20

< 1.0

< 1.0

< 1.0 5.2

< 1.0

< 1.0

< 1.0 13 8.5 1.1 6.1 3

12 2.9 0.173 0.0106 0.046 0.101 U

-0.0978 U

-0.0224 U

-0.0817 U

< 0.0500

< 0.0700

< 0.200

< 0.200 0.258 U

-1.23 U NA W-52 10/03/19

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 1.39 0.0212 1.3

-0.521 U 0.121 U 0.115 0.00124 U

< 0.050

< 0.070

< 0.200

< 0.200 1.61 U

-20.8 U NA 04/09/20

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.992 0.0272 2.0 2.41 U 0.0567 U 0.00430 U 0.00348 U

< 0.0500

< 0.0700

< 0.200

< 0.200 2.43 U

-0.253 U NA W-53 10/03/19

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0 4.0

< 0.80

< 0.80 4.4 1.0

< 0.80 5.2 0.081 0.0397 0.57 1.61 U 0.0359 U

-0.0157 U

-0.0614 U

< 0.050

< 0.070

< 0.200

< 0.200 1.72 U

-35.1 U NA 04/09/20

< 1.0

< 1.0 5.4

< 1.0 1.3

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0 1.5

< 0.80 4

0.017 0.108 0.033

-0.727 U

-0.0556 U 0.0382 U

-0.0627 U

< 0.0500

< 0.0700

< 0.200

< 0.200 3.20 U 0.874 U NA W-54 10/04/19

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.258 0.0037 2.8 1.55 U 0.0685 U

-0.0666 U 0.0126 U

< 0.050

< 0.070

< 0.200

< 0.200 1.96 U

-19.6 U NA 04/09/20

< 1.0

< 1.0 1.9

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.093 0.0156 1.7 0.275 U

-0.141 U 0.0287 U

-0.0479 U

< 0.0500

< 0.0700

< 0.200

< 0.200 1.60 U

-0.513 U NA W-55 10/04/19

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.062 0.0108 3.7 438 290 16.3 60.5 0.052 5.79 177 183 77.3

-11.9 U NA 04/08/20

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.047 0.0260 2.0 271 197 9.43 39.4 0.032 J 3.77 112 115 52.9

-1.04 U NA W-56 10/04/19

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.257 0.0090 4.2 264 192 9.18 37.9 0.034 J 4.19 130 134 54.5

-20.5 U NA 04/07/20

< 1.0

< 1.0 1.2

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.241 0.0110 2.8 60.9 47.7 2.29 9.79

< 0.0500 0.98 30 31 10.1

-1.35 U NA W-57 10/03/19

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.057 0.0155 4.6 0.202 U

-0.0917 U 0 U 0.0165 U

< 0.050

< 0.070 0.207 0.207 3.09 U

-16.3 U NA 04/07/20

< 1.0

< 1.0 1.7

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.073 0.0155 3.5 8.21 0.00106 U 0.0293 U

-0.0225 U

< 0.0500

< 0.0700

< 0.200

< 0.200 5.21

-0.855 U NA W-58 10/04/19

< 1.0

< 1.0 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.180 18.6 9.7 4.21 2.10 0.104 U 0.331 U

< 0.050 0.049 J 1.67 1.72 2.43 U

-26.1 U NA 04/07/20

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.099 6.28 4.3 2.39 U 1.62

-0.0132 U 0.399

< 0.0500 0.0326 J 1.02 1.05 1.85 U

-0.0365 U NA W-59 10/05/19

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 4.18 12.3 14 44.4 38.0 2.02 8.26

< 0.050 0.659 21.6 22.2 17.4 13.0 U NA 04/07/20

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 2.90 8.82 20 25.3 20.1 0.927 4.58

< 0.0500 0.379 12.4 12.8 9.33 7.86 NA W-60 10/17/19

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.034 0.0251 0.035 0.200 U 0.0248 U 0.0418 U 0.00356 U

< 0.050

< 0.070

< 0.200

< 0.200 1.38 U

-7.75 U NA 04/10/20

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.024 0.128

< 0.020 0.543 U

-0.0712 U

-0.00912 U

-0.0148 U

< 0.0500

< 0.0700

< 0.200

< 0.200 3.08 U

-1.89 U NA W-61 10/17/19

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.036 0.0274 2.5 1.31 U

-0.0719 U 0.0596 U 0.0254 U

< 0.050

< 0.070

< 0.200

< 0.200 0.862 U

-16.1 U NA 04/10/20

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.041 0.0550 1.4 0.373 U 0.0228 U

-0.0101 U 0.00788 U

< 0.0500

< 0.0700

< 0.200

< 0.200 6.86

-0.660 U NA W-62 10/22/19

< 1.0

< 1.0

< 1.0

< 1.0 42

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.019 0.0162 4.0

-0.106 U 0.0178 U 0.0998 U 0.142 U

< 0.050

< 0.070

< 0.200

< 0.200 4.85

-17.3 U NA 04/17/20

< 1.0

< 1.0

< 1.0

< 1.0 45 1

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.001 0.0127 4.3 1.40 U 0.0392 U

-0.0123 U

-0.0199 U

< 0.0500

< 0.0700

< 0.200

< 0.200

-2.46 U 0.361 U NA W-63 10/21/19

< 1.0

< 1.0

< 1.0

< 1.0 1.0 1.1

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.259 0.0230 0.34 1.22 U 0.266 U 0.0677 U 0.264 U

< 0.050

< 0.070 0.123 J 0.123 J 3.32 U

-21.0 U NA 04/21/20

< 1.0

< 1.0 1.9

< 1.0 160 4.9

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.191 0.0674 0.43 2.89 U 0.613 0.0539 U 0.323

< 0.0500

< 0.0700 0.686 0.686 9.10 3.26 U NA W-64 10/17/19

< 1.0

< 1.0

< 1.0

< 1.0 1.3

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 4.27 16.0 42 4.11 U 0.0871 U 0.0256 U 0.0239 U

< 0.050

< 0.070

< 0.200

< 0.200 70.3 81.9 NA 04/20/20

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 4.10 16.1 40 5.82 0.616 0.0329 U 0.226

< 0.0500

< 0.0700 0.28 0.28 0.969 U

-0.556 U NA W-65 10/17/19

< 1.0

< 1.0 13

< 1.0 220 84

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.783 0.0489 0.64 1.22 U

-0.0554 U

-0.0400 U 0.0898 U

< 0.050

< 0.070

< 0.200

< 0.200 7.14

-20.1 U NA 04/24/20

< 1.0

< 1.0 13

< 1.0 300 76

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.44 0.0230 0.75 2.07 U 0.0103 U

-0.00428 U 0.0493 U

< 0.0500

< 0.0700

< 0.200

< 0.200

-1.04 U 1.19 U NA W-66 10/17/19

< 5.0

< 5.0 22

< 5.0 480 8.5

< 5.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.076 0.0336 1.5

-0.144 U 0.0479 U 0.00220 U 0.0800 U

< 0.050

< 0.070

< 0.200

< 0.200 3.33 U

-10.5 U NA 04/24/20

< 1.0

< 1.0 18

< 1.0 360 7.6

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.047 0.0177 1.5 0.673 U

-0.00661 U 0.0452 U 0.0178 U

< 0.0500

< 0.0700

< 0.200

< 0.200 3.87

-0.0286 U NA W-67 10/18/19

< 1.0

< 1.0 1.5

< 1.0 49 8.4

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.010 1.31 14 0.945 U

-0.0325 U 0 U 0.0343 U

< 0.050

< 0.070

< 0.200

< 0.200 65.3 84.3 NA 04/21/20

< 1.0

< 1.0 1.7

< 1.0 46 8.4

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.018 2.01 16 3.78 U

-0.0443 U

-0.000237 U 0.0474 U

< 0.0500

< 0.0700

< 0.200

< 0.200 55.6 86.5 NA W-68 10/22/19

< 1.0

< 1.0

< 1.0

< 1.0 110 1.8

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.020 0.0143 3.0 0.922 U 0.204 U 0.0452 U 0.0102 U

< 0.050

< 0.070

< 0.200

< 0.200 2.33 U

-31.1 U NA 04/20/20

< 1.0

< 1.0

< 1.0

< 1.0 110 1.7

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.089 0.0452 2.9 3.23 U 0.0317 U

-0.000204 U

-0.0170 U

< 0.0500

< 0.0700

< 0.200

< 0.200 5.89 0.409 U NA W-69 10/23/19

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.022 0.0341 0.16 2.31 U 0.366 0.118 U 0.201 U

< 0.050

< 0.070

< 0.200

< 0.200 1.94 U

-5.87 U NA 04/16/20

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80

< 0.10 0.0307 0.23 0.581 U

-0.00505 U 0.0242 U 0.00948 U

< 0.0500

< 0.0700

< 0.200

< 0.200 0.885 U

-0.314 U NA W-70 10/23/19

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80

< 0.10 0.0077 1.4 0.0198 U 0.188 U

-0.0415 U 0.0615 U

< 0.050

< 0.070

< 0.200

< 0.200 1.37 U 21.4 U NA 04/16/20

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80

< 0.10 0.0125 1.5 5.42

-0.0591 U

-0.0744 U

-0.0123 U

< 0.0500

< 0.0700

< 0.200

< 0.200 1.95 U

-0.552 U NA W-71 10/23/19

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.084 0.0149 0.021 0.983 U 0.228 U 0.0113 U 0.0743 U

< 0.050

< 0.070 0.165 J 0.165 J 8.11 12.2 U NA 04/16/20

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80

< 0.10 0.0156

< 0.02 4.72

-0.0215 U

-0.000314 U 0.0375 U

< 0.0500

< 0.0700 0.0765 J 0.0765 J 4.39 1.27 U NA W-72 10/04/19

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.116 0.275 1.5 1.05 U 0.125 U

-0.0117 U 0.0205 U

< 0.050

< 0.070 0.095 J 0.095 J 2.74 U

-17.1 U NA 04/03/20

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 1.08 0.0322 6.3 2.98 U 1.17 0.0265 U 0.162

< 0.0500 0.021 J 0.667 0.688 8.51 1.33 U NA Page 3 of 5

Table 4 Summary of Groundwater Analytical Results Westinghouse Columbia Fuel Fabrication Facility Hopkins, South Carolina AECOM Project No. 60595649 Carbon Disulfide ug/L Chloroform ug/L cis-1,2-Dichloroethene ug/L Ethylbenzene ug/L Tetrachloroethene ug/L Trichloroethene ug/L Vinyl Chloride ug/L 1,1'-Biphenyl ug/L 2-Methylnaphthalene ug/L Acenaphthene ug/L Carbazole ug/L Fluorene ug/L Naphthalene ug/L Phenanthrene ug/L Fluoride mg/L Ammonia NH3(N) mg/L Nitrate NO3 mg/L Gross Alpha pCi/L Isotopic Uranium 233/234 pCi/L Isotopic Uranium 235/236 pCi/L Isotopic Uranium 238 (HASL300) pCi/L Isotopic Uranium 234 ug/L Isotopic Uranium 235 ug/L Isotopic Uranium 238 ug/L Total Uranium ug/L Gross Beta pCi/L Tc-99 pCi/L Tritium pCi/L 70 700 5

5 2

4 10 15

• 30 50

• 900 Well Date Radionuclides Inorganics MCL/Action Level VOCs SVOCs W-73 10/04/19

< 1.0

< 1.0 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.071 0.0167 2.0 0.241 U

-0.00420 U 0.0655 U 0.121 U

< 0.050

< 0.070 0.0831 J 0.0831 J 1.85 U

-23.0 U NA 04/03/20

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80

< 0.10 0.0383 1.4

-2.20 U 0.155 U 0.0780 U

-0.0258 U

< 0.0500

< 0.0700 0.0873 J 0.0873 J 2.27 U

-1.62 U NA W-74 10/09/19

< 1.0

< 1.0 1.9

< 1.0 19 4.5

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.019 0.159 4.9

-0.595 U 0.111 U 0.00238 U 0.0963 U

< 0.050

< 0.070

< 0.200

< 0.200 1.29 U 11.5 U NA 04/08/20

< 1.0

< 1.0 1.6

< 1.0 19 4.2

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.010 0.0129 5.4

-0.164 U

-0.0540 U

-0.0593 U

-0.00979 U

< 0.0500

< 0.0700

< 0.200

< 0.200 2.38 U

-1.38 U NA W-75 10/09/19

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.109 0.391 0.063 2.10 U 0.0135 U 0.0780 U 0.00143 U

< 0.050

< 0.070

< 0.200

< 0.200 3.89 U

-15.8 U NA 04/08/20

< 1.0

< 1.0

< 1.0

< 1.0 1

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.068 0.268 1.6 1.80 U

-0.0429 U

-0.0219 U 0.00834 U

< 0.0500

< 0.0700

< 0.200

< 0.200 3.68

-1.17 U NA W-76 10/05/19

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0 63

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 1.45 0.0154 9.8 2.77 U 1.60

-0.0126 U 0.354

< 0.050 0.0308 J 0.915 0.946 6.88

-14.6 U NA 04/14/20

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0 44

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 1.40 0.0163 8.7 12.7 4.92 0.196 0.830

< 0.0500 0.0999 2.87 2.97 4.56 U

-0.741 U NA W-77 10/06/19

< 1.0 11

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 9.21 7.11 12 865 511 26.0 81.0 0.089 10.1 237 247 111 101 NA 04/14/20

< 1.0 11

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 7.39 17.0 20 399 591 28.5 88.7 0.104 11.2 253 264 41.7 5.10 NA W-78 10/05/19

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 13.4 0.0271 3.5

-0.146 U 0.0921 U 0.0466 U 0.105 U

< 0.050

< 0.070 0.0933 J 0.0933 J 4.12 U

-6.50 U NA 04/14/20

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 11.3 0.0286 4.4 1.82 U 0.0631 U 0.0946 U 0.0207 U

< 0.0500

< 0.0700 0.203 0.203 2.97 U 0.0509 U NA W-79 10/07/19

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 2.40 0.0146 4.0 2.99 U 0.0539 U

-0.0112 U 0.115 U

< 0.050

< 0.070 0.0892 J 0.0892 J 5.90 3.52 U NA 04/13/20

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.323 0.0099 5.1 0.312 U

-0.0423 U

-0.00965 U 0.0449 U

< 0.0500

< 0.0700

< 0.200

< 0.200 5.06 0.135 U NA W-80 10/06/19

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 1.57 0.0927 8.3 1.30 U 0.154 U 0.0254 U 0.0695 U

< 0.050

< 0.070 0.151 J 0.151 J 7.29 2.56 U NA 04/14/20

< 1.0 2.3

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.121 0.0158 16 3.43 0.167 U 0.0226 U 0.106 U

< 0.0500

< 0.0700 0.177 J 0.177 J 9.42

-1.32 U NA W-81 10/08/19

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.042 0.0762 3.1

-0.177 U 0.00840 U

-0.0482 U 0.112 U

< 0.050

< 0.070 0.0728 J 0.0728 J 1.23 U

-11.9 U NA 04/14/20

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.067 0.381 1.4 5.29 0.349 0.0590 U 0.150 U

< 0.0500

< 0.0700 0.393 0.393 8.64

-0.0743 U NA W-82 10/08/19

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.046 0.0275 0.99 1.37 U 0.0453 U 0 U 0.140 U

< 0.050

< 0.070 0.151 J 0.151 J 4.82

-1.54 U NA 04/14/20

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.041 0.0209 1.8 2.27 U 0.0344 U 0.00931 U 0.00738 U

< 0.0500

< 0.0700

< 0.200

< 0.200 6.49

-1.65 U NA W-83 10/08/19 2.1 1.3

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.079 0.0099 0.76 0.300 U 0.603 0.161 U

-0.0584 U

< 0.050

< 0.070

< 0.200

< 0.200 2.75 U 0.914 U NA 04/13/20

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.104 0.0099 0.80 1.90 U 0.0991 U 0.0149 U 0.0242 U

< 0.0500

< 0.0700

< 0.200

< 0.200 3.68 U

-2.64 U NA W-84 10/08/19

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.087 0.0119

< 0.020

-0.286 U 0.0661 U 0.0491 U

-0.00952 U

< 0.050

< 0.070 0.0704 J 0.0704 J 3.97 U

-9.22 U NA 04/13/20

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.107 0.0202

< 0.020 4.27 0.0943 U 0.00983 U 0.0161 U

< 0.0500

< 0.0700

< 0.200

< 0.200 6.12

-1.79 U NA W-85 10/23/19

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.230 0.0300 0.039 1.42 U 0.0494 U 0.0621 U 0.0502 U

< 0.050

< 0.070

< 0.200

< 0.200 1.23 U 19.3 U NA 04/28/20

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.217 0.129 0.023 1.74 U

-0.0346 U 0.0349 U 0.00884 U

< 0.0500

< 0.0700

< 0.200

< 0.200 3.47

-0.860 U NA W-86 10/23/19

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.511 0.0073

< 0.020 0.317 U 0.125 U 0.130 U 0.137 U

< 0.050

< 0.070

< 0.200

< 0.200 7.12 8.88 U NA 04/28/20

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.473 0.0137

< 0.020 1.90 U 0.0841 U 0.00967 U 0.0315 U

< 0.0500

< 0.0700

< 0.200

< 0.200 0.0942 U

-0.335 U NA W-87 10/02/19

< 1.0

< 1.0 2.0

< 1.0 38 11

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.278 0.0127 0.055 1.68 U 0.175 U 0.00163 U 0.151 U

< 0.050

< 0.070 0.457 0.457 4.92 0.787 U NA 04/15/20

< 1.0

< 1.0

< 1.0

< 1.0 41 8.6

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.239 0.0306 0.045 3.87 0.0251 U

-0.0151 U

-0.000241 U < 0.0500

< 0.0700 0.139 J 0.139 J 1.57 U

-0.866 U NA W-88 10/22/19

< 1.0

< 1.0

< 1.0

< 1.0 4.1

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.012 0.0127 4.5 2.50 U 0.107 U 0.0449 U 0.185 U

< 0.050

< 0.070

< 0.200

< 0.200 2.05 U 6.34 U NA 04/17/20

< 1.0

< 1.0

< 1.0

< 1.0 3.9

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80

< 0.10 0.0157 4.3 3.63 0.0393 U

-0.0131 U

-0.0108 U

< 0.0500

< 0.0700

< 0.200

< 0.200 4.16 U 1.15 U NA W-89 10/22/19

< 1.0

< 1.0

< 1.0

< 1.0 2.1

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.011 0.0132 2.5 0.498 U 0.209 U

-0.0110 U

-0.0178 U

< 0.050

< 0.070

< 0.200

< 0.200

-0.799 U 27.5 U NA 04/17/20

< 1.0

< 1.0

< 1.0

< 1.0 6.7

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.001 0.0336 2.5 1.61 U

-0.0349 U 0.0379 U

-0.0106 U

< 0.0500

< 0.0700

< 0.200

< 0.200 1.25 U

-1.06 U NA W-90 10/22/19

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.039 0.0147 2.3 0.889 U 0.0370 U 0.0653 U

-0.0139 U

< 0.050

< 0.070

< 0.200

< 0.200 23.1 6.68 U NA 04/17/20

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80

< 0.10 0.0174 1.4 3.85

-0.0455 U

-0.0134 U

-0.0428 U

< 0.0500

< 0.0700

< 0.200

< 0.200 2.69 U

-0.242 U NA W-92 10/10/19

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.099 3.19 0.029 1.58 U 0.0426 U

-0.0270 U 0.0765 U

< 0.050

< 0.070

< 0.200

< 0.200 3.78 U

-10.2 U NA 04/27/20

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.100 4.11

< 0.020 0.372 U 0.0370 U 0.0378 U

-0.0314 U

< 0.0500

< 0.0700

< 0.200

< 0.200 2.51 U 2.49 U NA W-93 10/06/19

< 1.0

< 1.0

< 1.0

< 1.0 24 2.8

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.043 0.0324 5.3 3.06 0.115 U 0.0644 U 0.0900 U

< 0.050

< 0.070

< 0.200

< 0.200 8.18

-29.0 U NA 04/14/20

< 1.0

< 1.0

< 1.0

< 1.0 28 3.6

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.017 0.0139 4.6 1.12 U

-0.00215 U 0.0396 U 0.0238 U

< 0.0500

< 0.0700

< 0.200

< 0.200 3.82 U

-0.623 U NA W-94 10/15/19

< 1.0

< 1.0 5.3

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.043 0.246

< 0.020 1.14 U 0.0614 U

-0.0102 U 0.0262 U

< 0.050

< 0.070

< 0.200

< 0.200 2.48 U 20.4 U NA 04/24/20

< 1.0

< 1.0 5.6

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.043 0.245

< 0.020 0.640 U 0.129 U

-0.0187 U

-0.0524 U

< 0.0500

< 0.0700

< 0.200

< 0.200 0.552 U

-1.04 U NA W-95 10/15/19

< 1.0

< 1.0 4.3

< 1.0

< 1.0

< 1.0 2.9

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.077 0.145 0.024 0.695 U 0.0378 U 0.0692 U 0.0560 U

< 0.050

< 0.070 0.114 J 0.114 J 0.814 U 2.35 U NA 04/24/20

< 1.0

< 1.0 3.7

< 1.0

< 1.0

< 1.0 2.9

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.050 0.174 0.037 1.22 U 0.108 U 0.0369 U 0.00597 U

< 0.0500

< 0.0700

< 0.200

< 0.200 1.90 U

-0.108 U NA Page 4 of 5

Table 4 Summary of Groundwater Analytical Results Westinghouse Columbia Fuel Fabrication Facility Hopkins, South Carolina AECOM Project No. 60595649 Carbon Disulfide ug/L Chloroform ug/L cis-1,2-Dichloroethene ug/L Ethylbenzene ug/L Tetrachloroethene ug/L Trichloroethene ug/L Vinyl Chloride ug/L 1,1'-Biphenyl ug/L 2-Methylnaphthalene ug/L Acenaphthene ug/L Carbazole ug/L Fluorene ug/L Naphthalene ug/L Phenanthrene ug/L Fluoride mg/L Ammonia NH3(N) mg/L Nitrate NO3 mg/L Gross Alpha pCi/L Isotopic Uranium 233/234 pCi/L Isotopic Uranium 235/236 pCi/L Isotopic Uranium 238 (HASL300) pCi/L Isotopic Uranium 234 ug/L Isotopic Uranium 235 ug/L Isotopic Uranium 238 ug/L Total Uranium ug/L Gross Beta pCi/L Tc-99 pCi/L Tritium pCi/L 70 700 5

5 2

4 10 15

• 30 50

• 900 Well Date Radionuclides Inorganics MCL/Action Level VOCs SVOCs W-96 10/11/19

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.111 0.228 0.054 2.51 U 0.0695 U 0.108 U 0.0719 U

< 0.050

< 0.070

< 0.200

< 0.200 4.36

-1.25 U NA 04/24/20

< 1

< 1.0

< 1.0

< 1.0 1.2

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.059 0.165

< 0.020 0.667 U 0.0173 U

-0.000182 U 0.110 U

< 0.0500

< 0.0700

< 0.200

< 0.200 3.11 U 0.00377 U NA W-97 10/11/19

< 1.0

< 1.0

< 1.0

< 1.0 4.3 1.2

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.375 4.89 3.4 0.168 U 0.106 U 0.0403 U 0.0495 U

< 0.050

< 0.070

< 0.200

< 0.200 11.0 10.3 U NA 04/24/20

< 1.0

< 1.0

< 1.0

< 1.0 9.8 2

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.233 2.32 6.0 6.24 0.0625 U 0.00869 U

-0.0452 U

< 0.0500

< 0.0700

< 0.200

< 0.200 53.8 88.3 NA Notes:

ug/L - Micrograms per liter mg/L - Milligrams per liter pCi/L - Picocuries per liter MCL - Maximum Contaminant Level

• - site specific action level Tc Technetium-99 NA - Not analyzed U - Analyte was not detected above the minimun detectable level, concentration, or activity J - Estimated result is less than the practical quantitation limit and greater than the method detection limit Page 5 of 5

2019/2020 Annual Groundwater Monitoring Report Project number: 60595649 Prepared for: Westinghouse Electric Company, LLC AECOM Figures

Dominion Energy Substation CFFF 101 Research Drive Columbia, SC 29203 T: (803) 254-4400 F: (803) 771-6676 PROJECT NO.

PREPARED BY:

DATE:

60595649 CCS August 2020 FIGURE 1 q

0 4,000 2,000 Feet 1:48,000 Map Projection: NAD 1983, South Carolina State Plane, FIPS 3900, Feet Datum: North American 1983 Data Source: Esri/USGS WESTINGHOUSE COLUMBIA FUEL FABRICATION FACILITY HOPKINS, SOUTH CAROLINA Site Location Map Path: M:\\EnvDataViz\\Westinghouse\\mxd\\2020 Revised Phase II WP\\fig_1_sitelocationmap.mxd

^_

Legend Locations Property Line Topographic Quadrangle Boundary 1

2 3

4 5

6 Southwest Columbia Gaston Fort Jackson South Saylors Lake Congaree Gadsden ID Topographic Quadrangle Name 1

2 4

3 5

6

Dominion Energy Substation Mill Creek Plant Building Wastewater Treatment Plant Gator Pond Lower Sunset Lake Upper Sunset Lake Bluff Road (SC Hwy 48)

Canal Mill Creek Culvert Culvert Western Ditch Middle Ditch Eastern Ditch Denley Cemetery 101 Research Drive Columbia, SC 29203 T: (803) 254-4400 F: (803) 771-6676 PROJECT NO.

PREPARED BY:

DATE:

60595649 CCS August 2020 FIGURE 2 q

0 1,000 500 Feet 1:12,000 Map Projection: NAD 1983, South Carolina State Plane, FIPS 3900, Feet Datum: North American 1983 WESTINGHOUSE COLUMBIA FUEL FABRICATION FACILITY HOPKINS, SOUTH CAROLINA Property Map Path: M:\\EnvDataViz\\Westinghouse\\mxd\\2020 Revised Phase II WP\\fig_2_PropertyMap.mxd Legend SCRDI Bluff Road (Superfund Site)

Dike Location Mill Creek Flow Direction

?

Ditch Culvert Mill Creek Property Line

?

?

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?

A A

A A

A A

A A

A A

A A

A A

A A

A A

A A

A A

A A

A A

A A

A A

A A

A A

A A

A A

A A

A A

A@

A A

A A

A A

A A

A A

A A

A A

A A

A A

A A

A A

A A

A A

A A

A A

A A

A A @

A A

A A

A A

A A

A A

A A

A

")

")

")

")

Plant Building WL2 WL1 SAN NL EL SL Gator Pond Culvert Eastern Ditch Dominion Energy Substation Western Ditch Middle Ditch Former Oil House Denley Cemetery W-11 W-27 W-32 W-3A W-4 W-42 W-47 W-49 W-64 W-61 W-60 W-69 W-70 W-71 W-85 W-86 W-90 W-92 W-91 W-RW2 W-10 W-13R W-14 W-15 W-16 W-19B W-20 W-23R W-24 W-26 W-33 W-36 W-39 W-41R W-43 W-44 W-46 W-48 W-7A W-62 W-63 W-67 W-68 W-88 W-89 W-97 W-96 W-95 W-94 W-25 Creek Upper Gator Lower 101 Research Drive Columbia, SC 29203 T: (803) 254-4400 F: (803) 771-6676 PROJECT NO.

PREPARED BY:

DATE:

60595649 CCS August 2020 FIGURE 3 q

0 600 300 Feet 1:7,200 Map Projection: NAD 1983, South Carolina State Plane, FIPS 3900, Feet Datum: North American 1983 WESTINGHOUSE COLUMBIA FUEL FABRICATION FACILITY HOPKINS, SOUTH CAROLINA Site Map Path: M:\\EnvDataViz\\Westinghouse\\mxd\\2020 Revised Phase II WP\\fig_3_SiteMap.mxd Legend East Lagoon North Lagoon South Lagoon Sanitary Lagoon West Lagoon I West Lagoon II EL NL SL SAN WL1 WL2 Upper Surficial Aquifer Monitoring Well Location Lower Surficial Monitoring Well Location Black Mingo Monitoring Well A

A A

?

Ditch Culvert Upper Sunset Lake Lower Sunset Lake Mill Creek SCRDI Bluff Road (Superfund Site)

Mill Creek Flow Direction Mill Creek Property Line Dike Location

?

?

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A A

A A

A A

A A

A A

A A

A A

A A

A A

A A

A A

A A

A A

A A

A A

A A

A A

A A

A A

A A

A A

A A

A A

A Plant Building WL2 WL1 SAN NL EL SL W-75 W-78 W-77 W-66 W-65 W-59 W-58 W-57 W-56 W-55 W-54 W-53 W-52 W-51 W-7A W-6 W-50 W-45 W-43 W-40 W-39 W-38 W-37 W-36 W-35 W-33 W-30 W-29 W-28 W 10 W-RW1 W-22 W-18R W-17 W-72 W-73 W-74 W-93 W-79 W-80 W-81 W-82 W-83 W-84 W-87 W-86 W-76 Staff Gauge Location

")

Top of Bluff Inferred Top of Bluff Bottom of Bluff Inferred Bottom of Bluff Secondary Bluff Area Lower Sunset Dike Upper Sunset Dike Canal

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Plant Building WL2 WL1 SAN NL EL SL Gator Pond Upper Sunset Lake Lower Sunset Lake Eastern Ditch Middle Ditch Former Oil House Eastern Ditch Denley Cemetery Mechanical Area Wastewater Treatment Southern Storage Area West Lagoon Area Western Storage Area Chemical Area Sanitary Lagoon Western Groundwater AOC Northern Storage Area 101 Research Drive Columbia, SC 29203 T: (803) 254-4400 F: (803) 771-6676 PROJECT NO.

PREPARED BY:

DATE:

60595649 CCS August 2020 FIGURE 4 q

0 300 150 Feet 1:3,600 Map Projection: NAD 1983, South Carolina State Plane, FIPS 3900, Feet Datum: North American 1983 WESTINGHOUSE COLUMBIA FUEL FABRICATION FACILITY HOPKINS, SOUTH CAROLINA Operational Units Map Path: M:\\EnvDataViz\\Westinghouse\\mxd\\2020 Revised Phase II WP\\fig_4_OperationUnitsMap.mxd Legend East Lagoon North Lagoon South Lagoon Sanitary Lagoon West Lagoon I West Lagoon II EL NL SL SAN WL1 WL2 Operable Units Western Groundwater AOC Western Storage Area West Lagoons Area

?

Ditch Culvert Mill Creek Mill Creek Flow Direction Dike Location Chemical Area Southern Storage Area Mechanical Area Northern Storage Area Wastewater Treatment Area Sanitary Lagoon Area

W-14 120.14' W-15 115.00' W-16 121.31' W-32 121.02' W-61 121.64' W-62 (114.79')

W-64 115.50' W-67 115.72' W-70 (126.12')

W-85 (116.68')

W-89 120.72' W-91 115.25' W-92 (105.56')

W-10 120.31' W-11 (121.74')

W-13R 123.17' W-19B (117.68')

W-23R 121.28' W-24 130.16' W-27 110.59' W-33 (123.48')

W-36 127.63' W-39 124.90' W-4 (105.71')

W-41R 117.87' W-42 114.64' W-43 (125.68')

W-44 (116.44')

W-46 120.72' W-47 (114.91')

W-48 (115.35')

W-60 (118.08')

W-63 (113.71')

W-69 130.89' W-7A 122.71' W-86 (118.18')

W-88 (119.68')

W-90 (115.95')

W-68 (108.63')

W-94 (105.90')

W-97 109.50 W-26 115.84 Gator (117.16')

W-RW2 (121.31')

W-95 (105.69')

W-96 105.38' W-20 105.56' W-25 104.93' Upper (109.01')

Lower (108.65')

Creek (105.69')

110 130 115 125 120 105 101 Research Drive Columbia, SC 29203 T: (803) 254-4400 F: (803) 771-6676 PROJECT NO.

PREPARED BY:

DATE:

60595649 RGM June 2020 FIGURE 5 q

0 600 300 Feet 1:7,200 Map Projection: North American Datum (NAD) 1983, South Carolina State Plane, FIPS 3900, Feet WESTINGHOUSE COLUMBIA FUEL FABRICATION FACILITY HOPKINS, SOUTH CAROLINA Surficial Aquifer Potentiometric Map October 2019 Path: M:\\EnvDataViz\\Westinghouse\\mxd\\2020_AprilSemiAnnualGWMonRep\\fig_5_SurficialPot-Oct2019.mxd 124.90' Groundwater Elevation (127.46') Elevation for illustrative purposes only Based upon data from October 14, 2019 Legend East Lagoon North Lagoon South Lagoon Sanitary Lagoon West Lagoon I West Lagoon II EL NL SL SAN WL1 WL2 Upper Sunset Lake Lower Sunset Lake Mill Creek Plant Building WL2 WL1 SAN NL EL SL W-6 (125.24')

W-45 127.17' W-52 127.04' W-54 126.99' W-55 126.91' W-57 126.76' W-58 125.74' W-59 125.65' W-66 127.19' W-75 126.79' W-76 127.57' W-77 126.55' W-78 126.26' W-80 124.79' W-81 124.41' W-82 123.51' W-RW1 (127.31')

W-17 (124.71')

W-18R (124.51')

W-22 124.83' W-28 126.28' W-29 126.20' W-30 126.16' W-35 127.29' W-37 126.99' W-38 126.06' W-40 127.31' W-51 127.24' W-53 127.12' W-56 126.93' W-65 (126.88')

W-72 127.05' W-73 126.84' W-74 (126.47')

W-79 127.06' W-83 121.86' W-84 127.54' W-87 (127.46')

W-93 (126.07')

Lower Sunset Dike Upper Sunset Dike Lower Surficial Aquifer A

Upper Surficial Aquifer A

Direction of Groundwater Potentiometric Line (C.I. = 5 feet, dashed where inferred)

Mill Creek Flow Direction SCRDI Bluff Road (Superfund Site)

Property Line Mill Creek Culvert

?

Ditch Inferred Top of Bluff Top of Bluff Staff Gauge Location

")

Dike Location Secondary Bluff Area Inferred Bottom of Bluff Bottom of Bluff

W-14 122.60' W-15 116.70' W-16 123.00' W-32 122.49' W-4 (112.80')

W-42 116.41' W-48 (117.31')

W-61 124.01' W-62 (115.72')

W-64 117.54' W-70 (130.54')

W-85 (119.84')

W-89 122.78' W-92 (109.05')

W-RW2 (122.03')

W-20 109.24' W-25 108.48' W-68 (110.94')

W-94 (109.53')

W-95 (109.37')

W-96 109.07' W-97 112.63' W-10 121.94' W-11 (123.51')

W-13R 125.33' W-19B (118.95')

W-23R 122.95' W-24 134.26' W-26 118.01' W-27 112.15' W-33 (124.43')

W-36 130.04' W-39 126.26' W-41R 118.84' W-43 128.02' W-44 (117.48')

W-46 121.25' W-47 (116.89')

W-60 (119.43')

W-63 (115.02')

W-67 118.69' W-7A 124.19' W-86 (121.01')

W-88 (121.68')

W-90 (117.49')

W-69 133.10' W-91 117.11' 120 115 110 125 130 101 Research Drive Columbia, SC 29203 T: (803) 254-4400 F: (803) 771-6676 PROJECT NO.

PREPARED BY:

DATE:

60595649 CCS August 2020 FIGURE 6 q

0 600 300 Feet 1:7,200 Map Projection: NAD 1983, South Carolina State Plane, FIPS 3900, Feet Datum: North American 1983 WESTINGHOUSE COLUMBIA FUEL FABRICATION FACILITY HOPKINS, SOUTH CAROLINA Path: M:\\EnvDataViz\\Westinghouse\\mxd\\2020_AprilSemiAnnualGWMonRep\\fig_6_PotentiometricMap-April2020.mxd Upper Sunset Lake Lower Sunset Lake Mill Creek Plant Building WL2 WL1 SAN NL EL SL W-29 127.51' W-82 125.40' W-40 129.26' W-45 129.10' W-51 129.21' W-53 128.94' W-54 128.87' W-55 128.71' W-57 128.23' W-58 127.07' W-6 (126.81')

W-66 129.16' W-75 128.45' W-77 128.06' W-78 127.56' W-80 126.80' W-81 126.03' W-RW1 (129.33')

W-17 (125.68')

W-18R (125.76')

W-22 126.61' W-28 127.56' W-30 127.41' W-35 129.32' W-37 128.79' W-38 127.41' W-52 128.99' W-56 128.68' W-59 126.82' W-65 (128.80')

W-72 128.86' W-73 128.56' W-74 (128.05')

W-76 127.50' W-79 128.52' W-83 123.77' W-84 130.59' W-87 (129.54')

W-93 (127.94')

130 125 125 Lower Sunset Dike Upper Sunset Dike Surficial Aquifer Potentiometric Map April 2020 126.26' Groundwater Elevation (129.54') Elevation for illustrative purposes only Based upon data from April 6, 2020 Legend East Lagoon North Lagoon South Lagoon Sanitary Lagoon West Lagoon I West Lagoon II EL NL SL SAN WL1 WL2 Direction of Groundwater Potentiometric Line (C.I. = 5 feet, dashed where inferred)

Mill Creek Flow Direction SCRDI Bluff Road (Superfund Site)

Property Line Mill Creek Culvert

?

Ditch Inferred Top of Bluff Top of Bluff Staff Gauge Location

")

Dike Location Secondary Bluff Area Inferred Bottom of Bluff Bottom of Bluff Surficial Aquifer - Upper Zone Monitoring Well A

Surficial Aquifer - Lower Zone Monitoring Well A

Denley Cemetery

A A

A A

Upper Sunset Dike Lower Sunset Dike Mill Creek Lower Sunset Lake Upper Sunset Lake Gator Pond EL SL NL SAN WL1 WL2 Plant Building Denley Cemetery W-3A 111.29' W-49 109.18' W-50 114.31 W-71 114.74 110 114 112 101 Research Drive Columbia, SC 29203 T: (803) 254-4400 F: (803) 771-6676 PROJECT NO.

PREPARED BY:

DATE:

60595649 CCS FIGURE 7 q

0 400 200 Feet 1:4,800 Map Projection: NAD 1983, South Carolina State Plane, FIPS 3900, Feet Datum: North American 1983 WESTINGHOUSE COLUMBIA FUEL FABRICATION FACILITY HOPKINS, SOUTH CAROLINA Path: M:\\EnvDataViz\\Westinghouse\\mxd\\2020_AprilSemiAnnualGWMonRep\\fig_7_BlackMingo_Pot-Oct2019.mxd August 2020 Black Mingo Aquifer Potentiometric Map October 2019 A

Black Mingo Aquifer Monitoring Well 114.31' Groundwater Elevation Based upon data from October 14, 2019 Legend East Lagoon North Lagoon South Lagoon Sanitary Lagoon West Lagoon I West Lagoon II EL NL SL SAN WL1 WL2 Direction of Groundwater Potentiometric Line (C.I. = 5 feet, dashed where inferred)

Mill Creek Flow Direction SCRDI Bluff Road (Superfund Site)

Property Line Mill Creek Culvert

?

Ditch Inferred Top of Bluff Top of Bluff Dike Location Secondary Bluff Area Inferred Bottom of Bluff Bottom of Bluff

Upper Sunset Dike Lower Sunset Dike Mill Creek Lower Sunset Lake Upper Sunset Lake Gator Pond EL SL NL SAN WL1 WL2 Plant Building Denley Cemetery W-3A 115.18' W-49 113.10' W-50 118.06' W-71 133.10' 114 118 116 101 Research Drive Columbia, SC 29203 T: (803) 254-4400 F: (803) 771-6676 PROJECT NO.

PREPARED BY:

DATE:

60595649 CCS FIGURE 8 q

0 400 200 Feet 1:4,800 Map Projection: NAD 1983, South Carolina State Plane, FIPS 3900, Feet Datum: North American 1983 WESTINGHOUSE COLUMBIA FUEL FABRICATION FACILITY HOPKINS, SOUTH CAROLINA Path: M:\\EnvDataViz\\Westinghouse\\mxd\\2020_AprilSemiAnnualGWMonRep\\fig_8_BlackMingo_Pot-April2020.mxd August 2020 Black Mingo Aquifer Potentiometric Map April 2020 A

Black Mingo Aquifer Monitoring Well 118.06' Groundwater Elevation Based upon data from April 6, 2020 Legend East Lagoon North Lagoon South Lagoon Sanitary Lagoon West Lagoon I West Lagoon II EL NL SL SAN WL1 WL2 Direction of Groundwater Potentiometric Line (C.I. = 5 feet, dashed where inferred)

Mill Creek Flow Direction SCRDI Bluff Road (Superfund Site)

Property Line Mill Creek Culvert

?

Ditch Inferred Top of Bluff Top of Bluff Dike Location Secondary Bluff Area Inferred Bottom of Bluff Bottom of Bluff

A A

A A

A A

A A

A A

A A

A A

A A

A A

A A

A A

A A

A A

A A

A A

A A

A@

A A

A A@

A A

A A

A A

A A

A A

A A

A A

A A

A A

A A

A A

Plant Building WL2 WL1 SAN NL SL EL Gator Pond Denley Cemetery W-66 480 W-72

< 1.0 W-73

< 1.0 W-79

< 1.0 W-83

< 1.0 W-86

< 1.0 W-10

< 1.0 W-13R 15 W-14 1.1 W-15 12 W-16 7.8 W-22

< 1.0 W-23R

< 1.0 W-26

< 1.0 W-27

< 1.0 W-28

< 1.0 W-29

< 1.0 W-30

< 1.0 W-32 1.4 W-35 2.6 W-36

< 1.0 W-37

< 1.0 W-38 1.8 W-39 290 W-4

< 1.0 W-40

< 1.0 W-41R 190 W-42

< 1.0 W-43

< 1.0 W-45

< 1.0 W-46 2.5 W-51

< 1.0 W-52

< 1.0 W-53

< 1.0 W-54

< 1.0 W-55

< 1.0 W-56

< 1.0 W-57

< 1.0 W-58

< 1.0 W-59

< 1.0 W-61

< 1.0 W-64 1.3 W-67 49 W-69

<1.0 W-75

< 1.0 W-76

< 1.0 W-77

< 1.0 W-78

< 1.0 W-7A 1.9 W-80

< 1.0 W-81

< 1.0 W-82

< 1.0 W-84

< 1.0 W-89 2.1 W-11 1.1 W-20

<1.0 W-97 4.3 W-96

<1.0 W-91 NS 5

5 1

1 1

101 Research Drive Columbia, SC 29203 T: (803) 254-4400 F: (803) 771-6676 PROJECT NO.

PREPARED BY:

DATE:

60595649 RGM FIGURE 9 q

0 400 200 Feet 1:4,800 Map Projection: NAD 1983, South Carolina State Plane, FIPS 3900, Feet Datum: North American 1983 WESTINGHOUSE COLUMBIA FUEL FABRICATION FACILITY HOPKINS, SOUTH CAROLINA Extent of PCE Surficial Aquifer - Upper Zone October 2019 Path: M:\\EnvDataViz\\Westinghouse\\mxd\\2020_AprilSemiAnnualGWMonRep\\fig_9_PCE_UpperSurf_Oct2019.mxd PCE Concentration in µg/L Not Sampled East Lagoon North Lagoon South Lagoon Sanitary Lagoon West Lagoon 1 West Lagoon 2 480 NS EL NL SL SAN WL1 WL2 Note:

Based upon data collected in October 2019 August 2020 Upper Sunset Lake Lower Sunset Lake Mill Creek Lower Sunset Dike Upper Sunset Dike Legend

?

Ditch Culvert Dike Location Mill Creek Mill Creek Flow Direction Top of Bluff Inferred Top of Bluff Bottom of Bluff Inferred Bottom of Bluff Secondary Bluff Area PCE Isoconcentration Contour (µg/L)

PCE Inferred Isoconcentration Contour (µg/L)

PCE Isoconcentration Contour at a Concentration Less Than the Maximum Contaminant Level (µg/L)

A Surficial Aquifer - Upper Zone Monitoring Well

A A

A A

A A

A A

A A

A A

A A

A A

A A

A A

A A

A A

A A

A A

A A

A A

A@

A A

A A@

A A

A A

A A

A A

A A

A A

A A

A A

A A

A A

A A

Upper Sunset Dike Lower Sunset Dike Mill Creek Lower Sunset Lake Upper Sunset Lake Gator Pond EL SL NL SAN WL1 WL2 Plant Building Denley Cemetery W-38 1.4 W-40

< 1 W-54

< 1 W-57

< 1 W-73

< 1 W-4

< 1 W-7A 1.6 W-10

< 1 W-13R 14 W-14 4.8 W-15 7.2 W-16 5.6 W-20

< 1 W-22

< 1 W-23R

< 1 W-26

< 1 W-27

< 1 W-28

< 1 W-29

< 1 W-30

< 1 W-32

< 1 W-35 2.5 W-36

< 1 W-37

< 1 W-39 390 W-41R 180 W-42

< 1 W-43

< 1 W-45

< 1 W-46 2.2 W-51

< 1 W-52

< 1 W-53 1.3 W-55

< 1 W-56

< 1 W-58

< 1 W-59

< 1 W-61

< 1 W-64

< 1 W-66 360 W-67 46 W-69

< 1 W-72

< 1 W-75 1

W-76

< 1 W-77

< 1 W-78

< 1 W-79

< 1 W-80

< 1 W-81

< 1 W-82

< 1 W-83

< 1 W-84

< 1 W-86

< 1 W-89 6.7 W-91

< 1 W-96 1.2 W-97 9.8 W-11 1.4 1

1 5

5 5

1 1

101 Research Drive Columbia, SC 29203 T: (803) 254-4400 F: (803) 771-6676 PROJECT NO.

PREPARED BY:

DATE:

60595649 CCS FIGURE 10 q

0 400 200 Feet 1:4,800 Map Projection: NAD 1983, South Carolina State Plane, FIPS 3900, Feet Datum: North American 1983 WESTINGHOUSE COLUMBIA FUEL FABRICATION FACILITY HOPKINS, SOUTH CAROLINA Extent of PCE Surficial Aquifer - Upper Zone April 2020 Path: M:\\EnvDataViz\\Westinghouse\\mxd\\2020_AprilSemiAnnualGWMonRep\\fig_10_PCE_UpperSurf_April2020.mxd PCE Concentration in µg/L Not Sampled East Lagoon North Lagoon South Lagoon Sanitary Lagoon West Lagoon 1 West Lagoon 2 390 NS EL NL SL SAN WL1 WL2 Note:

Based upon data collected in April 2020 June 2020 Legend

?

Ditch Culvert Dike Location Mill Creek Mill Creek Flow Direction Top of Bluff Inferred Top of Bluff Bottom of Bluff Inferred Bottom of Bluff Secondary Bluff Area PCE Isoconcentration Contour (µg/L)

PCE Inferred Isoconcentration Contour (µg/L)

PCE Isoconcentration Contour at a concentration less than the maximum contaminant level (µg/L)

A Surficial Aquifer - Upper Zone Monitoring Well

Plant Building WL2 WL1 SAN NL SL EL Gator Pond 5

Denley Cemetery W-85

< 1 W-17 4.3 W-19B 150 W-33 300 W-44

< 1.0 W-47 1.6 W-48 200 W-6 16 W-60

< 1.0 W-62 42 W-63 1.0 W-65 220 W-71

<1.0 W-74 19 W-87 38 W-88 4.1 W-90

< 1.0 W-92

< 1.0 W-93 24 W-RW1 1.4 W-RW2 140 W-18R 3.15 W-68 110 W-95

<1.0 W-94

<1.0 5

5 5

1 1

5 1

5 1

101 Research Drive Columbia, SC 29203 T: (803) 254-4400 F: (803) 771-6676 PROJECT NO.

PREPARED BY:

DATE:

60595649 RGM FIGURE 11 q

0 410 205 Feet 1:4,800 Map Projection: NAD 1983, South Carolina State Plane, FIPS 3900, Feet Datum: North American 1983 WESTINGHOUSE COLUMBIA FUEL FABRICATION FACILITY HOPKINS, SOUTH CAROLINA Path: M:\\EnvDataViz\\Westinghouse\\mxd\\2020_AprilSemiAnnualGWMonRep\\fig_11_PCE_LowerSurf_Oct2019.mxd PCE Concentration in µg/L East Lagoon North Lagoon South Lagoon Sanitary Lagoon West Lagoon 1 West Lagoon 2 300 EL NL SL SAN WL1 WL2 Note:

Based upon data collected in October 2019 August 2020 Upper Sunset Lake Lower Sunset Lake Mill Creek Lower Sunset Dike Upper Sunset Dike Extent of PCE Surficial Aquifer - Lower Zone October 2019 Legend

?

Ditch Culvert Dike Location Mill Creek Flow Direction Mill Creek Top of Bluff Inferred Top of Bluff Bottom of Bluff Inferred Bottom of Bluff Secondary Bluff Area PCE Isoconcentration Contour (µg/L)

PCE Inferred Isoconcentration Contour (µg/L)

PCE Isoconcentration Contour at a Concentration Less Than the Maximum Contaminant Level (µg/L)

A Surficial Aquifer - Lower Zone Monitoring Well

A A

A A

A A

A A

A A

A A

A A

A A

A A

A A

A A

A A

A Upper Sunset Dike Lower Sunset Dike Mill Creek Lower Sunset Lake Upper Sunset Lake Gator Pond EL SL NL SAN WL1 WL2 Plant Building Denley Cemetery 5

5 5

5 5

1 1

1 1

W-RW1 1.7 W-RW2 140 W-6 19 W-17 2.0 W-19B 130 W-33 270 W-44

< 1.0 W-47 1.6 W-60

< 1.0 W-62 45 W-65 300 W-68 110 W-70

< 1.0 W-74 19 W-87 41 W-88 3.9 W-90

< 1.0 W-92

< 1.0 W-93 28 W-94

< 1.0 W-95

< 1.0 W-48 160 W-63

< 1.0 W-18R 3.4 W-85

< 1.0 101 Research Drive Columbia, SC 29203 T: (803) 254-4400 F: (803) 771-6676 PROJECT NO.

PREPARED BY:

DATE:

60595649 CCS FIGURE 12 q

0 410 205 Feet 1:4,800 Map Projection: NAD 1983, South Carolina State Plane, FIPS 3900, Feet Datum: North American 1983 WESTINGHOUSE COLUMBIA FUEL FABRICATION FACILITY HOPKINS, SOUTH CAROLINA Path: M:\\EnvDataViz\\Westinghouse\\mxd\\2020_AprilSemiAnnualGWMonRep\\fig_12_PCE_LowerSurf_April2020.mxd PCE Concentration in µg/L East Lagoon North Lagoon South Lagoon Sanitary Lagoon West Lagoon 1 West Lagoon 2 300 EL NL SL SAN WL1 WL2 Note:

Based upon data collected in April 2020 April 2020 Extent of PCE Surficial Aquifer - Lower Zone April 2020 Legend

?

Ditch Culvert Dike Location Mill Creek Flow Direction Mill Creek Top of Bluff Inferred Top of Bluff Bottom of Bluff Inferred Bottom of Bluff Secondary Bluff Area PCE Isoconcentration Contour (µg/L)

PCE Inferred Isoconcentration Contour (µg/L)

PCE Isoconcentration Contour at a concentration less than the Maximum Contaminant Level (µg/L)

A Surficial Aquifer - Lower Zone Monitoring Well

Plant Building WL2 WL1 SAN NL SL EL Gator Pond Denley Cemetery W-38 11 W-66 8.5 W-72

< 1.0 W-73

< 1.0 W-75

< 1.0 W-77

< 1.0 W-79

< 1.0 W-83

< 1.0 W-86

< 1.0 W-10

< 1.0 W-13R 1.4 W-14

< 1.0 W-15 2.0 W-16 2.2 W-22

< 1.0 W-23R

< 1.0 W-26

< 1.0 W-27

< 1.0 W-28

< 1.0 W-29

< 1.0 W-30

< 1.0 W-32

< 1.0 W-35

< 1.0 W-36

< 1.0 W-37

< 1.0 W-39 5.2 W-4

< 1.0 W-40

< 1.0 W-41R 14 W-42

< 1.0 W-43

< 1.0 W-45

< 1.0 W-46

< 1.0 W-51

< 1.0 W-52

< 1.0 W-53

< 1.0 W-54

< 1.0 W-55

< 1.0 W-56

< 1.0 W-57

< 1.0 W-58

< 1.0 W-59

< 1.0 W-61

< 1.0 W-64

< 1.0 W-67 8.4 W-69

< 1.0 W-76 63 W-78

< 1.0 W-7A

< 1.0 W-80

< 1.0 W-81

< 1.0 W-82

< 1.0 W-84

< 1.0 W-89

< 1.0 W-11

< 1.0 W-20

<1.0 W-97 1.2 W-96

<1.0 W-90 NS 5

5 1

5 1

1 101 Research Drive Columbia, SC 29203 T: (803) 254-4400 F: (803) 771-6676 PROJECT NO.

PREPARED BY:

DATE:

60595649 RGM FIGURE 13 q

0 410 205 Feet 1:4,800 Map Projection: NAD 1983, South Carolina State Plane, FIPS 3900, Feet Datum: North American 1983 WESTINGHOUSE COLUMBIA FUEL FABRICATION FACILITY HOPKINS, SOUTH CAROLINA Path: M:\\EnvDataViz\\Westinghouse\\mxd\\2020_AprilSemiAnnualGWMonRep\\fig_13_TCE_UpperSurf_Oct2019.mxd TCE Concentration in µg/L East Lagoon North Lagoon South Lagoon Sanitary Lagoon West Lagoon 1 West Lagoon 2 63 EL NL SL SAN WL1 WL2 Note:

Based upon data collected in October 2019 August 2020 Upper Sunset Lake Lower Sunset Lake Mill Creek Lower Sunset Dike Upper Sunset Dike Extent of TCE Surfical Aquifer - Upper Zone October 2019 Legend

?

Ditch Culvert Dike Location Mill Creek Flow Direction Mill Creek Top of Bluff Inferred Top of Bluff Bottom of Bluff Inferred Bottom of Bluff Secondary Bluff Area TCE Isoconcentration Contour (ug/L)

TCE Inferred Isoconcentration Contour (ug/L)

TCE Isoconcentration Contour at a Concentration Less Than the Maximum Contaminant Level (ug/L)

A Surficial Aquifer - Upper Zone Monitoring Well

Upper Sunset Dike Lower Sunset Dike Mill Creek Lower Sunset Lake Upper Sunset Lake Gator Pond EL SL NL SAN WL1 WL2 Plant Building Denley Cemetery W-38 5.7 W-54

< 1.0 W-57

< 1.0 W-73

< 1.0 W-11

< 1.0 W-4

< 1.0 W-7A

< 1.0 W-10

< 1.0 W-13R 1.3 W-14 1.3 W-15 1.4 W-16 1.7 W-20

< 1.0 W-22

< 1.0 W-23R

< 1.0 W-26

< 1.0 W-27

< 1.0 W-28

< 1.0 W-29

< 1.0 W-30

< 1.0 W-32

< 1.0 W-35

< 1.0 W-36

< 1.0 W-37

< 1.0 W-39 7.6 W-40

< 1.0 W-41R 4

W-42

< 1.0 W-43

< 1.0 W-45

< 1.0 W-46

< 1.0 W-51

< 1.0 W-52

< 1.0 W-53

< 1.0 W-55

< 1.0 W-56

< 1.0 W-58

< 1.0 W-59

< 1.0 W-61

< 1.0 W-64

< 1.0 W-66 7.6 W-67 8.4 W-69

< 1.0 W-72

< 1.0 W-75

< 1.0 W-76 44 W-77

< 1.0 W-78

< 1.0 W-79

< 1.0 W-80

< 1.0 W-81

< 1.0 W-82

< 1.0 W-83

< 1.0 W-84

< 1.0 W-86

< 1.0 W-89

< 1.0 W-91

< 1.0 W-96

< 1.0 W-97 2

5 5

1 5

1 1

101 Research Drive Columbia, SC 29203 T: (803) 254-4400 F: (803) 771-6676 PROJECT NO.

PREPARED BY:

DATE:

60595649 LJG FIGURE 14 1:4,800 Map Projection: NAD 1983, South Carolina State Plane, FIPS 3900, Feet Datum: North American 1983 WESTINGHOUSE COLUMBIA FUEL FABRICATION FACILITY HOPKINS, SOUTH CAROLINA Path: M:\\EnvDataViz\\Westinghouse\\mxd\\2020_AprilSemiAnnualGWMonRep\\fig_14_TCE_UpperSurf_April2020.mxd August 2020 Extent of TCE Surficial Aquifer - Upper Zone April 2020 Legend

?

Ditch Culvert Dike Location Mill Creek Flow Direction Mill Creek Top of Bluff Inferred Top of Bluff Bottom of Bluff Inferred Bottom of Bluff Secondary Bluff Area q

0 410 205 Feet TCE Concentration in ug/L Not Sampled East Lagoon North Lagoon South Lagoon Sanitary Lagoon West Lagoon 1 West Lagoon 2 8.4 NS EL NL SL SAN WL1 WL2 Note:

Based upon data collected in April 2020 TCE Isoconcentration Contour (ug/L)

TCE Inferred Isoconcentration Contour (ug/L)

TCE Isoconcentration Contour at a concentration less than the Maximum Contaminant Level (ug/L)

A Surficial Aquifer - Upper Zone Monitoring Well

Plant Building WL2 WL1 SAN NL SL EL Gator Pond Lower Sunset Lake Upper Sunset Lake W-18R

< 1.0 Denley Cemetery W-17

< 1.0 W-19B 2.5 W-33 38 W-44

< 1.0 W-47

< 1.0 W-48 4.9 W-6 2.5 W-60

< 1.0 W-62

< 1.0 W-63 1.1 W-65 84 W-70

< 1.0 W-74 4.5 W-87 11 W-88

< 1.0 W-90

< 1.0 W-92

< 1.0 W-93 2.8 W-RW1

< 1.0 W-RW2 8.3 W-85

<1.0 W-68 1.8 W-95

<1.0 W-94

<1.0 5

1 1

1 1

1 101 Research Drive Columbia, SC 29203 T: (803) 254-4400 F: (803) 771-6676 PROJECT NO.

PREPARED BY:

DATE:

60595649 RGM FIGURE 15 q

0 410 205 Feet 1:4,800 Map Projection: NAD 1983, South Carolina State Plane, FIPS 3900, Feet Datum: North American 1983 WESTINGHOUSE COLUMBIA FUEL FABRICATION FACILITY HOPKINS, SOUTH CAROLINA Path: M:\\EnvDataViz\\Westinghouse\\mxd\\2020_AprilSemiAnnualGWMonRep\\fig_15_TCE_LowerSurf_Oct2019.mxd TCE Concentration in µg/L East Lagoon North Lagoon South Lagoon Sanitary Lagoon West Lagoon 1 West Lagoon 2 84 EL NL SL SAN WL1 WL2 Note:

Based upon data collected in October 2019 August 2020 Extent of TCE Surficial Aquifer - Lower Zone October 2019 Legend

?

Ditch Culvert Mill Creek Flow Direction Mill Creek Top of Bluff Inferred Top of Bluff Bottom of Bluff Inferred Bottom of Bluff Secondary Bluff Area TCE Isoconcentration Contour (ug/L)

TCE Inferred Isoconcentration Contour (ug/L)

TCE Inferred Isoconcentration Contour at a Concentration Less Than the Maximum Contamminant Level (ug/L)

A Surficial Aquifer - Lower Zone Monitoring Well

A A

A A

A A

A A

A A

A A

A A

A A

A A

A A

A A

A A

A Upper Sunset Dike Lower Sunset Dike Mill Creek Lower Sunset Lake Upper Sunset Lake Gator Pond EL SL NL SAN WL1 WL2 Plant Building Denley Cemetery W-RW1

< 1.0 W-RW2 11 W-6 2.7 W-17

< 1.0 W-19B 2.3 W-33 33 W-44

< 1.0 W-47

< 1.0 W-48 4.9 W-60

< 1.0 W-62 1.0 W-63 1.2 W-65 76 W-68 1.7 W-70

< 1.0 W-74 4.2 W-87 8.6 W-88

< 1.0 W-90

< 1.0 W-92

< 1.0 W-93 3.6 W-94

< 1.0 W-95

< 1.0 W-18R

< 1.0 W-85

< 1.0 5

1 1

101 Research Drive Columbia, SC 29203 T: (803) 254-4400 F: (803) 771-6676 PROJECT NO.

PREPARED BY:

DATE:

60595649 LJG FIGURE 16 Map Projection: NAD 1983, South Carolina State Plane, FIPS 3900, Feet Datum: North American 1983 WESTINGHOUSE COLUMBIA FUEL FABRICATION FACILITY HOPKINS, SOUTH CAROLINA Path: M:\\EnvDataViz\\Westinghouse\\mxd\\2020_AprilSemiAnnualGWMonRep\\fig_16_TCE_LowerSurf_April2020.mxd August 2020 Extent of TCE Surficial Aquifer - Lower Zone April 2020 Legend

?

Ditch Culvert Mill Creek Flow Direction Mill Creek Top of Bluff Inferred Top of Bluff Bottom of Bluff Inferred Bottom of Bluff Secondary Bluff Area 1:4,800 q 0

410 205 Feet TCE Concentration in ug/L Not Sampled East Lagoon North Lagoon South Lagoon Sanitary Lagoon West Lagoon 1 West Lagoon 2 76 NS EL NL SL SAN WL1 WL2 Note:

Based upon data collected in April 2020 TCE Isoconcentration Contour (ug/L)

TCE Inferred Isoconcentration Contour (ug/L)

TCE Isoconcentration Contour at a concentration less than the Maximum Contaminant Level (ug/L)

A Surficial Aquifer - Lower Zone Monitoring Well

Plant Building WL2 WL1 SAN NL SL EL Gator Pond Denley Cemetery W-32 170 W-38 4.3 W-4 0.023 W-49

< 0.020 W-50

< 0.020 W-54 2.8 W-6 210 W-64 42 W-65 0.64 W-70 1.4 W-72 1.5 W-73 2.0 W-75 0.063 W-77 12 W-79 4.0 W-83 0.76 W-86

< 0.020 W-89 2.5 W-93 5.3 W-RW1 2.1 W-10 37 W-11 56 W-13R 18 W-14 0.061 W-15 35 W-16 3.2 W-17 16 W-18R 770 W-19B 3.8 W-20

< 0.020 W-22 100 W-23R 0.71 W-26 3.2 W-27

< 0.020 W-28 6.3 W-29 11 W-30 120 W-33 13 W-35 3.2 W-36 0.11 W-37 3.5 W-39 73 W-3A

< 0.020 W-40 4.3 W-41R 65 W-42 4.7 W-43 6.3 W-44 2.4 W-45 0.093 W-46 7.8 W-47 42 W-48 5.3 W-51 0.11 W-52 1.3 W-53 0.57 W-55 3.7 W-56 4.2 W-57 4.6 W-58 9.7 W-59 14 W-60 0.035 W-61 2.5 W-62 4.0 W-63 0.34 W-66 1.5 W-67 14 W-68 3.0 W-69 0.16 W-71 0.021 W-74 4.9 W-76 9.8 W-78 3.5 W-7A 390 W-80 8.3 W-81 3.1 W-82 0.99 W-84

< 0.020 W-85 0.039 W-87 0.055 W-88 4.5 W-90 2.3 W-92 0.029 W-94

< 0.020 W-95 0.024 W-96 0.054 W-97 3.4 W-RW2 20 W-91 NS 10 10 1

1 0.20 1

101 Research Drive Columbia, SC 29203 T: (803) 254-4400 F: (803) 771-6676 PROJECT NO.

PREPARED BY:

DATE:

60595649 LJG FIGURE 17 q

0 410 205 Feet 1:4,800 Map Projection: NAD 1983, South Carolina State Plane, FIPS 3900, Feet Datum: North American 1983 WESTINGHOUSE COLUMBIA FUEL FABRICATION FACILITY HOPKINS, SOUTH CAROLINA Path: M:\\EnvDataViz\\Westinghouse\\mxd\\2020_AprilSemiAnnualGWMonRep\\fig_17_Nitrate_Oct2019.mxd Nitrate Concentration in mg/L Not Sampled East Lagoon North Lagoon South Lagoon Sanitary Lagoon West Lagoon 1 West Lagoon 2 770 NS EL NL SL SAN WL1 WL2 Note:

Based upon data collected in October 2019 June 2020 Upper Sunset Lake Lower Sunset Lake Mill Creek Lower Sunset Dike Upper Sunset Dike Extent of Nitrate in Groundwater October 2019 Nitrate Isoconcentration Contour (mg/L)

Nitrate Inferred Isoconcentration Contour (mg/L)

Nitrate Isoconcentration Contour at a Concentration Less Than the Maximum Contaminant Level (mg/L)

Legend

?

Ditch Culvert Dike Location Mill Creek Flow Direction Mill Creek Top of Bluff Inferred Top of Bluff Bottom of Bluff Inferred Bottom of Bluff Secondary Bluff Area A

Surficial Aquifer - Upper Zone Monitoring Well A

Surficial Aquifer - Lower Zone Monitoring Well A

Black Mingo Aquifer Monitoring Well

A A

A A

A A

A A

A A

A A

A A

A A

A A

A A

A A

A A

A A

A A

A A

A A

A A

A A

A A

A A

A A

A A@

A A

A A

A A

A A@

A A

A A

A A

A A

A A

A A

A A

A A

A A

A A

A A

A A

A A

A A

A A

A A

A A

A A

Upper Sunset Dike Lower Sunset Dike Mill Creek Lower Sunset Lake Upper Sunset Lake Gator Pond EL SL NL SAN WL1 WL2 Plant Building Denley Cemetery W-6 190 W-14 0.11 W-18R 790 W-30 120 W-33 8.2 W-38 3.1 W-50

< 0.02 W-54 1.7 W-57 3.5 W-61 1.4 W-73 1.4 W-77 20 W-91 0.34 W-11 51 W-RW1 2

W-RW2 12 W-3A

< 0.02 W-4 1.4 W-7A 330 W-10 21 W-13R 13 W-15 36 W-16 2.5 W-17 13 W-19B 4.2 W-20 0.045 W-22 50 W-23R 0.88 W-26 2.5 W-27 0.076 W-28 7

W-29 17 W-32 140 W-35 3.3 W-36 0.056 W-37 2

W-39 72 W-40 2.4 W-41R 48 W-42 2.9 W-43 7.1 W-44 1.7 W-45 0.11 W-46 8.7 W-47 44 W-48 5.1 W-49

< 0.02 W-51 0.046 W-52 2

W-53 0.033 W-55 2

W-56 2.8 W-58 4.3 W-59 20 W-60

< 0.02 W-62 4.3 W-63 0.43 W-64 40 W-65 0.75 W-66 1.5 W-67 16 W-68 2.9 W-69 0.23 W-70 1.5 W-71

< 0.02 W-72 6.3 W-74 5.4 W-75 1.6 W-76 8.7 W-78 4.4 W-79 5.1 W-80 16 W-81 1.4 W-82 1.8 W-83 0.8 W-84

< 0.02 W-85 0.023 W-86

< 0.02 W-87 0.045 W-88 4.3 W-89 2.5 W-90 1.4 W-92

< 0.02 W-93 4.6 W-94

< 0.02 W-95 0.037 W-96

< 0.02 W-97 6

0.02 10 10 0.02 1

1 101 Research Drive Columbia, SC 29203 T: (803) 254-4400 F: (803) 771-6676 PROJECT NO.

PREPARED BY:

DATE:

60595649 LJG FIGURE 18 q

0 410 205 Feet 1:4,800 Map Projection: NAD 1983, South Carolina State Plane, FIPS 3900, Feet Datum: North American 1983 WESTINGHOUSE COLUMBIA FUEL FABRICATION FACILITY HOPKINS, SOUTH CAROLINA Path: M:\\EnvDataViz\\Westinghouse\\mxd\\2020_AprilSemiAnnualGWMonRep\\fig_18_Nitrate_April2020.mxd Nitrate Concentration in mg/L Not Sampled East Lagoon North Lagoon South Lagoon Sanitary Lagoon West Lagoon 1 West Lagoon 2 790 NS EL NL SL SAN WL1 WL2 Note:

Based upon data collected in April 2020 August 2020 Extent of Nitrate in Groundwater April 2020 Legend

?

Ditch Culvert Dike Location Mill Creek Flow Direction Mill Creek Top of Bluff Inferred Top of Bluff Bottom of Bluff Inferred Bottom of Bluff Secondary Bluff Area Nitrate Isoconcentration Contour (mg/L)

Nitrate Inferred Isoconcentration Contour (mg/L)

Nitrate Isoconcentration Contour at a concentration less than the Maximum Contaminant Level (mg/L)

A Surficial Aquifer - Upper Zone Monitoring Well A

Surficial Aquifer - Lower Zone Monitoring Well A

Black Mingo Aquifer Monitoring Well

Plant Building WL2 WL1 SAN NL SL EL Gator Pond Denley Cemetery W-RW2 0.099 W-91 NS W-32 3.66 W-38 0.176 W-4 4.86 W-49 0.003 W-50 0.035 W-6 0.126 W-64 4.27 W-65 0.783 W-70

< 0.100 W-72 0.116 W-73 0.071 W-75 0.109 W-77 9.21 W-79 2.4 W-83 0.079 W-86 0.511 W-89 0.011 W-92 0.099 W-93 0.043 W-RW1 0.055 W-10 3.32 W-11 0.021 W-13R 8.11 W-14 0.079 W-15 1.88 W-16 9.5 W-17 2.22 W-18R 6.34 W-19B 0.019 W-20 0.077 W-22 5.52 W-23R 0.017 W-26 1.42 W-27 3.97 W-28 5.45 W-29 4.8 W-30 8.06 W-33 0.152 W-35 0.025 W-36 0.007 W-37 0.02 W-39 0.024 W-3A 0.015 W-40 0.166 W-41R 0.03 W-42 1.99 W-43 0.111 W-44 0.023 W-45 0.633 W-46 0.033 W-47 4.45 W-48 0.33 W-51 0.215 W-52 1.39 W-53 0.081 W-54 0.258 W-55 0.062 W-56 0.257 W-57 0.057 W-58 0.18 W-59 4.18 W-60 0.034 W-61 0.036 W-62 0.019 W-63 0.259 W-66 0.076 W-67 0.01 W-68 0.02 W-69 0.022 W-71 0.084 W-74 0.019 W-76 1.45 W-78 13.4 W-7A 6.47 W-80 1.57 W-81 0.042 W-82 0.046 W-84 0.087 W-85 0.23 W-87 0.278 W-88 0.012 W-90 0.039 W-94 0.043 W-95 0.077 W-96 0.111 W-97 0.375 4

1 4

1 101 Research Drive Columbia, SC 29203 T: (803) 254-4400 F: (803) 771-6676 PROJECT NO.

PREPARED BY:

DATE:

60595649 LJG FIGURE 19 q

0 400 200 Feet 1:4,800 Map Projection: NAD 1983, South Carolina State Plane, FIPS 3900, Feet Datum: North American 1983 WESTINGHOUSE COLUMBIA FUEL FABRICATION FACILITY HOPKINS, SOUTH CAROLINA Path: M:\\EnvDataViz\\Westinghouse\\mxd\\2020_AprilSemiAnnualGWMonRep\\fig_19_Fluoride_Oct2019.mxd Fluoride Concentration in mg/L Not Sampled East Lagoon North Lagoon South Lagoon Sanitary Lagoon West Lagoon 1 West Lagoon 2 13.4 NS EL NL SL SAN WL1 WL2 Note:

Based upon data collected in October 2019 August 2020 Upper Sunset Lake Lower Sunset Lake Mill Creek Lower Sunset Dike Upper Sunset Dike Extent of Fluoride in Groundwater October 2019 Legend

?

Ditch Culvert Dike Location Mill Creek Flow Direction Mill Creek Top of Bluff Inferred Top of Bluff Bottom of Bluff Inferred Bottom of Bluff Secondary Bluff Area Fluoride Isoconcentration Contour (mg/L)

Fluoride Inferred Isoconcentration Contour (mg/L)

Fluoride Isoconcentration Contour Depression (mg/L)

Fluoride Isoconcentration Contour at a Concentration Less Than the Maximum Contaminant Level (mg/L)

A Surficial Aquifer - Upper Zone Monitoring Well A

Surficial Aquifer - Lower Zone Monitoring Well A

Black Mingo Aquifer Monitoring Well

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A A

A A

A A

A A

A A

A A

A A

A A

A A

A A

A A

A A

A A

A A

A A

A A

A A

A A

A A

A A

A A

A A@

A A

A A

A A

A A@

A A

A A

A A

A A

A A

A A

A A

A A

A A

A A

A A

A A

A A

A A

A A

A A

A A

A A

Upper Sunset Dike Lower Sunset Dike Mill Creek Lower Sunset Lake Upper Sunset Lake Gator Pond EL SL NL SAN WL1 WL2 Plant Building Denley Cemetery 0.1 4

4 4

0.1 4

0.1 1.0 0.1 1.0 0.1 1.0 W-32 3.5 W-35 0.022 W-38 0.191 W-4 4.89 W-49 0.011 W-50

< 0.1 W-54 0.093 W-6 0.112 W-64 4.1 W-65 0.44 W-70

< 0.1 W-71

< 0.1 W-72 1.08 W-73

< 0.1 W-74 0.01 W-86 0.473 W-89 0.001 W-91 0.033 W-92 0.1 W-RW1 0.06 W-10 2.95 W-11 0.017 W-13R 7.07 W-14 0.083 W-15 2.28 W-16 8.92 W-17 2.55 W-18R 4.6 W-19B 0.01 W-20 0.03 W-22 3.63 W-23R 0.022 W-26 1.53 W-27 4.02 W-28 5.43 W-29 3.77 W-30 7.98 W-33 0.146 W-36 0.014 W-37 0.029 W-39 0.021 W-3A

< 0.1 W-40 0.139 W-41R 0.007 W-42 1.6 W-43 0.018 W-44

< 0.1 W-45 0.61 W-46 0.028 W-47 3.92 W-48 0.36 W-51 0.173 W-52 0.992 W-53 0.017 W-55 0.047 W-56 0.241 W-57 0.073 W-58 0.099 W-59 2.9 W-60 0.024 W-61 0.041 W-62 0.001 W-63 0.191 W-66 0.047 W-67 0.018 W-68 0.089 W-69

< 0.1 W-75 0.068 W-79 0.323 W-7A 6.04 W-83 0.104 W-84 0.107 W-85 0.217 W-87 0.239 W-88

< 0.1 W-90

< 0.1 W-94 0.043 W-95 0.05 W-96 0.059 W-97 0.233 W-RW2 0.089 W-76 1.4 W-77 7.39W-93 0.017 W-78 11.3 W-80 0.121 W-81 0.067 W-82 0.041 101 Research Drive Columbia, SC 29203 T: (803) 254-4400 F: (803) 771-6676 PROJECT NO.

PREPARED BY:

DATE:

60595649 CCS FIGURE 20 q

0 400 200 Feet 1:4,800 Map Projection: NAD 1983, South Carolina State Plane, FIPS 3900, Feet NAD: North American Datum 1983 WESTINGHOUSE COLUMBIA FUEL FABRICATION FACILITY HOPKINS, SOUTH CAROLINA Path: M:\\EnvDataViz\\Westinghouse\\mxd\\2020_AprilSemiAnnualGWMonRep\\fig_20_Fluoride_April2020.mxd Fluoride Concentration in mg/L Not Sampled East Lagoon North Lagoon South Lagoon Sanitary Lagoon West Lagoon 1 West Lagoon 2 13.4 NS EL NL SL SAN WL1 WL2 Note:

Based upon data collected in April 2020 August 2020 Extent of Fluoride in Groundwater April 2020 Legend

?

Ditch Culvert Dike Location Mill Creek Flow Direction Mill Creek Top of Bluff Inferred Top of Bluff Bottom of Bluff Inferred Bottom of Bluff Secondary Bluff Area Fluoride Isoconcentration Contour (mg/L)

Fluoride Inferred Isoconcentration Contour (mg/L)

Fluoride Isoconcentration Contour at a concentration less than the Maximum Contaminant Level (mg/L)

Fluoride Isoconcentration Contour Depression (mg/L)

A Surficial Aquifer - Upper Zone Monitoring Well A

Surficial Aquifer - Lower Zone Monitoring Well A

Black Mingo Aquifer Monitoring Well

Plant Building WL2 WL1 SAN NL SL EL Gator Pond Denley Cemetery W-91 NS W-32 0.224 W-4 0.146 W-48

< 0.200 W-49 0.0695 W-50 0.101 W-6 0.232 W-64

< 0.200 W-65

< 0.200 W-70

< 0.200 W-83

< 0.200 W-86

< 0.200 W-89

< 0.200 W-92

< 0.200 W-RW1 0.0815 W-10 0.083 W-11

< 0.200 W-13R 0.139 W-14 0.368 W-15

< 0.200 W-16

< 0.200 W-17 0.0855 W-18R 4.1 W-19B

< 0.200 W-20

< 0.200 W-22 0.872 W-23R

< 0.200 W-26

< 0.200 W-27

< 0.200 W-33

< 0.200 W-35

< 0.200 W-36

< 0.200 W-39

< 0.200 W-3A

< 0.200 W-40

< 0.200 W-41R

< 0.200 W-42

< 0.200 W-43

< 0.200 W-44

< 0.200 W-45 1.00 W-46

< 0.200 W-47

< 0.200 W-51

< 0.200 W-60

< 0.200 W-61

< 0.200 W-62

< 0.200 W-63 0.123 W-66

< 0.200 W-67

< 0.200 W-68

< 0.200 W-69

< 0.200 W-71 0.165 W-7A 0.698 W-81 0.0728 W-82 0.151 W-84 0.0704 W-85

< 0.200 W-87 0.457 W-88

< 0.200 W-90

< 0.200 W-94

< 0.200 W-95 0.114 W-96

< 0.200 W-97

< 0.200 W-RW2 0.0743 30 0.2 30 0.2 0.2 101 Research Drive Columbia, SC 29203 T: (803) 254-4400 F: (803) 771-6676 PROJECT NO.

PREPARED BY:

DATE:

60595649 LJG FIGURE 21 q

0 400 200 Feet 1:4,800 Map Projection: NAD 1983, South Carolina State Plane, FIPS 3900, Feet Datum: North American 1983 Legend A

Surficial Aquifer - Upper Zone Monitoring Well A

Surficial Aquifer - Lower Zone Monitoring Well A

Black Mingo Aquifer Monitoring Well

?

Ditch Culvert Dike Location Mill Creek Flow Direction Mill Creek Top of Bluff Inferred Top of Bluff Bottom of Bluff Inferred Bottom of Bluff Secondary Bluff Area WESTINGHOUSE COLUMBIA FUEL FABRICATION FACILITY HOPKINS, SOUTH CAROLINA Extent of Uranium in Groundwater October 2019 Path: M:\\EnvDataViz\\Westinghouse\\mxd\\2020_AprilSemiAnnualGWMonRep\\fig_21_Uranium_Oct2019.mxd Total Uranium in µg/L Not Sampled East Lagoon North Lagoon South Lagoon Sanitary Lagoon West Lagoon 1 West Lagoon 2 247 NS EL NL SL SAN WL1 WL2 Note:

Based upon data collected in October 2019 NL SL EL W-54

< 0.200 W-55 183 W-58 1.72 W-73 0.0831 W-75

< 0.200 W-93

< 0.200 W-28 0.429 W-29 2.05 W-30 8.91 W-37 0.0936 W-38 0.183 W-52

< 0.200 W-53

< 0.200 W-56 134 W-57 0.207 W-59 22.2 W-72 0.095 W-74

< 0.200 W-76 0.946 W-77 247 W-78 0.0933 W-79 0.0892 W-80 0.151 30 30 0.2 0.2 June 2020 Upper Sunset Lake Lower Sunset Lake Mill Creek Lower Sunset Dike Upper Sunset Dike Uranium Isoconcentration Contour (µg/L)

Uranium Inferred Isoconcentration Contour (µg/L)

Uranim Isoconcetration Contour at or Above the Minimum Detectible Concentration (µg/L)

A A

A A

A A

A A

A A

A A

A A

A A

A A

A A

A A

A A

A A

A A

A A

A A

A A

A A

A A

A A

A A

A A@

A A

A A

A A

A A@

A A

A A

A A

A A

A A

A A

A A

A A

A A

A A

A A

A A

A A

A A

A A

A A

A A

A A

Upper Sunset Dike Lower Sunset Dike Mill Creek Lower Sunset Lake Upper Sunset Lake Gator Pond EL SL NL SAN WL1 WL2 Plant Building Denley Cemetery 30 30 0.2 0.2 0.2 0.2 0.2 W-RW1

< 0.200 W-4 0.181 J W-27

< 0.200 W-33

< 0.200 W-35

< 0.200 W-42

< 0.200 W-48

< 0.200 W-50 0.151 J W-65

< 0.200 W-66

< 0.200 W-70

< 0.200 W-86

< 0.200 W-89

< 0.200 W-91

< 0.200 W-11

< 0.200 W-RW2

< 0.200 W-3A 0.106 J W-6 0.183 J W-7A 0.716 W-10

< 0.200 W-13R 0.076 J W-14 0.36 W-15

< 0.200 W-16 0.0827 J W-17 0.121 J W-19B

< 0.200 W-20

< 0.200 W-22 0.61 W-23R

< 0.200 W-26

< 0.200 W-32 0.154 J W-36

< 0.200 W-39

< 0.200 W-40

< 0.200 W-41R

< 0.200 W-43

< 0.200 W-44

< 0.200 W-45

< 0.200 W-46

< 0.200 W-47 0.102 J W-49 0.0735 J W-51

< 0.200 W-60

< 0.200 W-61

< 0.200 W-62

< 0.200 W-63 0.686 W-64 0.28 W-67

< 0.200 W-68

< 0.200 W-69

< 0.200 W-71 0.0765 J W-81 0.393 W-82

< 0.200 W-83

< 0.200 W-84

< 0.200 W-85

< 0.200 W-87 0.139 J W-88

< 0.200 W-90

< 0.200 W-92

< 0.200 W-94

< 0.200 W-95

< 0.200 W-96

< 0.200 W-97

< 0.200 W-18R 4.37 101 Research Drive Columbia, SC 29203 T: (803) 254-4400 F: (803) 771-6676 PROJECT NO.

PREPARED BY:

DATE:

60595649 CCS FIGURE 22 q

0 400 200 Feet 1:4,800 Map Projection: NAD 1983, South Carolina State Plane, FIPS 3900, Feet Datum: North American 1983 Legend A

Surficial Aquifer - Upper Zone Monitoring Well A

Surficial Aquifer - Lower Zone Monitoring Well A

Black Mingo Aquifer Monitoring Well

?

Ditch Culvert Dike Location Mill Creek Flow Direction Mill Creek Top of Bluff Inferred Top of Bluff Bottom of Bluff Inferred Bottom of Bluff Secondary Bluff Area WESTINGHOUSE COLUMBIA FUEL FABRICATION FACILITY HOPKINS, SOUTH CAROLINA Extent of Uranium in Groundwater in April 2020 Path: M:\\EnvDataViz\\Westinghouse\\mxd\\2020_AprilSemiAnnualGWMonRep\\fig_22_Uranium_April2020.mxd Total Uranium in µg/L Not Sampled East Lagoon North Lagoon South Lagoon Sanitary Lagoon West Lagoon 1 West Lagoon 2 264 NS EL NL SL SAN WL1 WL2 Note:

Based upon data collected in April 2020.

A A

A A

A A

A A

A A

A A

A A

A A

A A

A A

A A

A A

NL SL EL W-77 264 W-28 0.71 W-29 1.38 W-30 7.08 W-37

< 0.200 W-38 0.092 J W-52

< 0.200 W-53

< 0.200 W-54

< 0.200 W-55 115 W-56 31 W-57

< 0.200 W-58 1.05 W-59 12.8 W-72 0.688 W-73 0.0873 J W-74

< 0.200 W-75

< 0.200 W-76 2.97 W-78 0.203 W-79

< 0.200 W-80 0.177 J W-93

< 0.200 30 30 0.2 0.2 0.2 August 2020 Uranium Isoconcentration Contour (µg/L)

Uranium Inferred Isoconcentration Contour (µg/L)

Uranim Isoconcetration Contour at or Above the Minimum Detectible Concentration (µg/L)

Plant Building WL2 WL1 SAN NL SL EL Gator Pond Denley Cemetery W-91 NS W-96

< 50.0 W-55

< 50.0 W-72

< 50.0 W-73

< 50.0 W-75

< 50.0 W-83

< 50.0 W-86

< 50.0 W-14

< 50.0 W-23R

< 50.0 W-26

< 50.0 W-27

< 50.0 W-35

< 50.0 W-36

< 50.0 W-37

< 50.0 W-39

< 50.0 W-4 41.3 W-50

< 50.0 W-41R

< 50.0 W-42

< 50.0 W-43

< 50.0 W-45

< 50.0 W-51

< 50.0 W-52

< 50.0 W-53

< 50.0 W-54

< 50.0 W-56

< 50.0 W-57

< 50.0 W-61

< 50.0 W-66

< 50.0 W-67 84.3 W-70

< 50.0 W-82

< 50.0 W-84

< 50.0 W-89

< 50.0 W-19B

< 50.0 W-20

< 50.0 W-33

< 50.0 W-44

< 50.0 W-48

< 50.0 W-60

< 50.0 W-62

< 50.0 W-63

< 50.0 W-65

< 50.0 W-68

< 50.0 W-69

< 50.0 W-74

< 50.0 W-87

< 50.0 W-88

< 50.0 W-90

< 50.0 W-92

< 50.0 W-94

< 50.0 W-95

< 50.0 W-97

< 50.0 W-RW1

< 50.0 W-RW2

< 50.0 W-71

< 50.0 W-49

< 50.0 W-3A

< 50.0 W-85

< 50.0 900 100 50 101 Research Drive Columbia, SC 29203 T: (803) 254-4400 F: (803) 771-6676 PROJECT NO.

PREPARED BY:

DATE:

60595649 RGM FIGURE 23 q

0 400 200 Feet 1:4,800 Map Projection: NAD 1983, South Carolina State Plane, FIPS 3900, Feet Datum: North American 1983 Legend A

Surficial Aquifer - Upper Zone Monitoring Well A

Surficial Aquifer - Lower Zone Monitoring Well A

Black Mingo Aquifer Monitoring Well

?

Ditch Culvert Dike Location Mill Creek Flow Direction Mill Creek Top of Bluff Inferred Top of Bluff Bottom of Bluff Inferred Bottom of Bluff Secondary Bluff Area WESTINGHOUSE COLUMBIA FUEL FABRICATION FACILITY HOPKINS, SOUTH CAROLINA Extent of Technetium-99 in Groundwater October 2019 Path: M:\\EnvDataViz\\Westinghouse\\mxd\\2020_AprilSemiAnnualGWMonRep\\fig_23_Technetium_Oct2019.mxd Technetium-99 Concentration in pCi/L Not Sampled East Lagoon North Lagoon South Lagoon Sanitary Lagoon West Lagoon 1 West Lagoon 2 321 NS EL NL SL SAN WL1 WL2 Note:

Based upon data collected in October 2019 August 2020 Upper Sunset Lake Lower Sunset Lake Mill Creek Lower Sunset Dike Upper Sunset Dike Gator Pond EL SL NL SAN W-32 321 W-58

< 50.0 W-6 2440 W-93

< 50.0 W-10 118 W-11 3420 W-13R 63.4 W-14

< 50.0 W-15 253 W-16

< 50.0 W-17 820 W-18R 214 W-22 57.4 W-28

< 50.0 W-29

< 50.0 W-30 49.7 W-38

< 50.0 W-46 62.8 W-47 94.2 W-59

< 50.0 W-64 81.9 W-67 84.3 W-76

< 50.0 W-77 101 W-78

< 50.0 W-79

< 50.0 W-7A 210 W-80

< 50.0 W-81

< 50.0 50 900 50 50 50 100 Tc-99 Isoconcentration Contour (pCi/L)

Tc-99 Inferred Isoconcentration Contour (pCi/L)

Tc-99 Isoconcetration Contour at or Above the Minimum Detectible Concentration (pCi/L)

Upper Sunset Dike Lower Sunset Dike Mill Creek Lower Sunset Lake Upper Sunset Lake Gator Pond EL SL NL SAN WL1 WL2 Plant Building Denley Cemetery W-35 0.0 W-49 0.0 W-55 0.0 W-73 0.0 W-RW1 0.209 U W-RW2 3.26 U W-3A 0.0 W-4 24.5 W-19B 0.0 W-20 0.0 W-23R 0.0 W-26 6.84 W-27 3.23 U W-33 2.90 U W-36 0.0 W-37 1.37 U W-39 7.39 W-40 0.0 W-41R 12.1 W-42 2.64 U W-43 1.60 U W-44 0.0 W-45 71.1 W-48 13.8 W-50 0.0 W-51 0.0 W-52 0.0 W-53 0.874 U W-54 0.0 W-56 0.0 W-60 0.0 W-61 0.0 W-62 0.361 U W-63 3.26 U W-65 1.19 U W-66 0.0 W-68 0.409 U W-69 0.0 W-70 0.0 W-71 1.27 U W-72 1.33 U W-74 0.0 W-75 0.0 W-82 0.0 W-83 0.0 W-84 0.0 W-85 0.0 W-86 0.0 W-87 0.0 W-88 1.15 U W-89 0.0 W-90 0.0 W-91 0.624 U W-92 2.49 U W-94 0.0 W-95 0.0 W-96 0.00377 U W-97 88.3 W-67 86.5 W-14 0.611 U W-81 0.0 W-80 0.0 W-78 0.0509 U W-77 5.10 W-79 0.135 U W-38 0.0 W-58 0.0 W-57 0.0 W-64 0.0 W-47 86.8 W-46 55.6 50 10 100 900 101 Research Drive Columbia, SC 29203 T: (803) 254-4400 F: (803) 771-6676 PROJECT NO.

PREPARED BY:

DATE:

60595649 CCS FIGURE 24 q

0 400 200 Feet 1:4,800 Map Projection: NAD 1983, South Carolina State Plane, FIPS 3900, Feet Datum: North American 1983 Legend A

Surficial Aquifer - Upper Zone Monitoring Well A

Surficial Aquifer - Lower Zone Monitoring Well A

Black Mingo Aquifer Monitoring Well

?

Ditch Culvert Dike Location Mill Creek Flow Direction Mill Creek Top of Bluff Inferred Top of Bluff Bottom of Bluff Inferred Bottom of Bluff Secondary Bluff Area WESTINGHOUSE COLUMBIA FUEL FABRICATION FACILITY HOPKINS, SOUTH CAROLINA Extent of Technetium-99 in Groundwater April 2020 Path: M:\\EnvDataViz\\Westinghouse\\mxd\\2020_AprilSemiAnnualGWMonRep\\fig_24_Technetium_April2020.mxd Technetium-99 Concentration in pCi/L Not Sampled East Lagoon North Lagoon South Lagoon Sanitary Lagoon West Lagoon 1 West Lagoon 2 270 NS EL NL SL SAN WL1 WL2 Note:

Based upon data collected in April 2020 August 2020 A

A A

A A

A A

A A

A A

A A

A A

A A

A A

A A

A Gator Pond EL SL NL SAN W-32 270 W-10 81.2 W-28 0.0 W-22 20.1 W-29 8.62 W-38 0.0 W-17 429 W-15 219 W-6 2450 W-13R 58.9 W-76 0.0 W-30 48.4 W-16 6.84 W-7A 180 W-59 7.86 W-11 3440 W-18R 295 900 50 100 50 10 Tc-99 Isoconcentration Contour (pCi/L)

Tc-99 Inferred Isoconcentration Contour (pCi/L)

Tc-99 Isoconcetration Contour at or Above the Minimum Detectible Concentration (pCi/L)

2019/2020 Annual Groundwater Monitoring Report Project number: 60595649 Prepared for: Westinghouse Electric Company, LLC AECOM Appendix A - Groundwater Sample Collections Records

2019/2020 Annual Groundwater Monitoring Report Project number: 60595649 Prepared for: Westinghouse Electric Company, LLC AECOM Appendix B - Laboratory Analytical Reports

2019/2020 Annual Groundwater Monitoring Report Project number: 60595649 Prepared for: Westinghouse Electric Company, LLC AECOM Appendix C - Historical Groundwater Monitoring Data

Table C-1 Summary of Historical Groundwater Analytical Results (2015-2020)

Westinghouse Columbia Fuel Fabrication Facility Hopkins, South Carolina AECOM Project No. 60595649 Carbon Disulfide ug/L Chloroform ug/L cis-1,2-Dichloroethene ug/L Ethylbenzene ug/L Tetrachloroethene ug/L Trichloroethene ug/L Vinyl Chloride ug/L 1,1'-Biphenyl ug/L 2-Methylnaphthalene ug/L Acenaphthene ug/L Carbazole ug/L Fluorene ug/L Naphthalene ug/L Phenanthrene ug/L Fluoride mg/L Ammonia NH3(N) mg/L Nitrate NO3 mg/L Gross Alpha pCi/L Isotopic Uranium 233/234 pCi/L Isotopic Uranium 235/236 pCi/L Isotopic Uranium 238 (HASL300) pCi/L Isotopic Uranium 234 ug/L Isotopic Uranium 235 ug/L Isotopic Uranium 238 ug/L Total Uranium ug/L Gross Beta pCi/L Tc-99 pCi/L Tritium pCi/L 70 700 5

5 2

4 10 15

• 30 50

• 900 20,000 Well Date W-RW1 04/16/19

< 1.0

< 1.0

< 1.0

< 1.0 1.3

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.04 0.0397 2.5 0.934 U

-0.0778 U 0.0695 U

-0.158 U

< 0.0500

< 0.0700

< 0.200

< 0.200 5.56

-0.108 U NA 10/03/19

< 1.0

< 1.0

< 1.0

< 1.0 1.4

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.055 0.0129 2.1 2.51 U 0.126 U 0.139 U 0.169 U

< 0.050

< 0.070 0.0815 J 0.0815 J 3.98 1.40 U NA 04/15/20

< 1.0

< 1.0

< 1.0

< 1.0 1.7

< 1.0

< 1.0

< 4.0

< 0.8

< 0.8

< 4.0

< 0.8

< 0.8

< 0.80 0.06 0.0196 2

1.01 U 0.195 U 0.0329 U

-0.00701 U

< 0.0500

< 0.0700

< 0.200

< 0.200 1.65 U 0.209 U NA W-RW2 01/12/15

< 1.0

< 1.0

< 1.0

< 1.0 110 6.3

< 2.0

< 5.1

< 5.1

< 5.1

< 5.1

< 5.1

< 5.1

< 5.1

<0.50

<1.00 30 1.15 U NA NA NA NA NA NA NA 11.5 22.9 U 21.2 U 04/09/15

< 1.0

< 1.0

< 1.0

< 1.0 140 12

< 1.0

< 5.0

< 5.0

< 5.0

< 5.0

< 5.0

< 5.0

< 5.0

<0.50

<1.00 19

-0.764 U NA NA NA NA NA NA NA 6.31

-53.1 U 57.8 U 07/10/15

< 1.0

< 1.0

< 1.0

< 1.0 120 8.9

< 1.0

< 5.0

< 5.0

< 5.0

< 5.0

< 5.0

< 5.0

< 5.0

<0.50

<1.00 21

-0.827 U NA NA NA NA NA NA NA 6.58

-17.6 U

-110 U 10/09/15

< 1.0

< 1.0

< 1.0

< 1.0 160 8.1

< 1.0

< 5.0

< 5.0

< 5.0

< 5.0

< 5.0

< 5.0

< 5.0

<0.50

<1.00 25 1.17 U NA NA NA NA NA NA NA 10.8 84.8 U

-93.6 U 01/20/16

< 1.0

< 1.0

< 1.0

< 1.0 81 7.3

< 1.0

< 5.0

< 5.0

< 5.0

< 5.0

< 5.0

< 5.0

< 5.0

<0.50

<1.00 19

-1.04 U NA NA NA NA NA NA NA 6.31 NA

-74.1 U 04/18/16

< 1.0

< 1.0

< 1.0

< 1.0 150 12

< 1.0

< 5.0

< 5.0

< 5.0

< 5.0

< 5.0

< 5.0

< 5.0

<0.50

<1.00 19 0.835 U NA NA NA NA NA NA NA 6.49 NA 216 U 07/05/16

< 1.0

< 1.0

< 1.0

< 1.0 160 9

< 2.0

< 5.4

< 5.4

< 5.4

< 5.4

< 5.4

< 5.4

< 5.4

<0.50

<1.00 23 2.35 U NA NA NA NA NA NA NA 8.32 NA 104 U 10/06/16

< 1.0

< 1.0

< 1.0

< 1.0 140 8.2

< 2.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80

<0.50

<1.00 24 2.68 NA NA NA NA NA NA NA 7.07 NA

-118 U 01/10/17

< 1.0

< 1.0

< 1.0

< 1.0 170 11

< 2.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80

<0.50

<1.00 20 2.79 U NA NA NA NA NA NA NA 6.56 NA

-94.2 U 04/03/17

< 1.0

< 1.0

< 1.0

< 1.0 150 10

< 2.0

< 8.0

< 1.6

< 1.6

< 8.0

< 1.6

< 1.6

< 1.6

<0.50

<1.00 19 4.09 U NA NA NA NA NA NA NA 7.10 NA 124 U 07/06/17

< 1.0

< 1.0

< 1.0

< 1.0 140 11

< 2.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80

<0.50

<1.00 19 3.13 NA NA NA NA NA NA NA 10.4 NA 212 U 10/12/17

< 1.0

< 1.0

< 1.0

< 1.0 120 7.9

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80

<0.50

<1.00 20 4.36 U NA NA NA NA NA NA NA 10.8 NA 179 U 01/09/18

< 1.0

< 1.0

< 1.0

< 1.0 160 9.8

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80

<0.50

<1.00 20 2.21 U NA NA NA NA NA NA NA 8.87 NA 40.7 U 04/10/18

< 1.0

< 1.0

< 1.0

< 1.0 170 9.7

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80

<0.50

<1.00 20 5.65 NA NA NA NA NA NA NA NA NA NA 07/10/18

< 1.0

< 1.0

< 1.0

< 1.0 170 5.6

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.101

<1.00 14 7.92 NA NA NA NA NA NA NA NA NA NA 10/16/18

< 1.0

< 1.0

< 1.0

< 1.0 190 7

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.098 0.0192 14 3.35 U NA NA NA NA NA NA NA NA NA NA 01/22/19

< 1.0

< 1.0

< 1.0

< 1.0 150 12

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.104 0.044 14 3.77 U 0.323 0.366 0.495

< 0.01

< 0.01 0.079 J 0.079 J 9.11

< 40

< 40 10/11/19

< 1.0

< 1.0

< 1.0

< 1.0 140 8.3

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 NA NA 20 2.00 U 0.252 U 0.107 U 0.0958 U

< 0.050

< 0.070 0.0743 J 0.0743 J 11.9 23.1 U 270 U 04/20/20

< 1.0

< 1.0

< 1.0

< 1.0 140 11

< 1.0

< 4.0

< 0.8

< 0.8

< 4.0

< 0.8

< 0.8

< 0.80 0.089 0.0204 12 3.17 U 0.00526 U

-0.00930 U 0.0482 U

< 0.0500

< 0.0700

< 0.200

< 0.200 3.53 U 3.26 U 79.8 U W-3A 01/21/15 NA NA NA NA NA NA NA NA NA NA NA NA NA NA

<0.50

<1.00

< 0.02 0.587 U NA NA NA NA NA NA NA 2.58 U

-40.2 U 51.3 U 04/16/15 NA NA NA NA NA NA NA NA NA NA NA NA NA NA

<0.50

<1.00

< 0.02 0.348 U NA NA NA NA NA NA NA 1.18 U

-77.0 U 320 U 07/16/15 NA NA NA NA NA NA NA NA NA NA NA NA NA NA

<0.50

<1.00

< 0.02 2.24 U NA NA NA NA NA NA NA 2.58 U

-1.71 U

-236 U 10/14/15 NA NA NA NA NA NA NA NA NA NA NA NA NA NA

<0.50

<1.00

< 0.02 0.170 U NA NA NA NA NA NA NA 2.86 U 74.7 U

-143 U 01/20/16 NA NA NA NA NA NA NA NA NA NA NA NA NA NA

<0.50

<1.00 0.034

-0.874 U NA NA NA NA NA NA NA 0.298 U NA

-42.9 U 04/21/16 NA NA NA NA NA NA NA NA NA NA NA NA NA NA

<0.50

<1.00

< 0.02 0.381 U NA NA NA NA NA NA NA 4.78 NA

-4.06 U 07/13/16 NA NA NA NA NA NA NA NA NA NA NA NA NA NA

<0.50

<1.00 0.11 2.82 NA NA NA NA NA NA NA 3.10 U NA NA 10/18/16 NA NA NA NA NA NA NA NA NA NA NA NA NA NA

<0.50

<1.00 0.039 1.20 U NA NA NA NA NA NA NA 7.30 NA NA 01/16/17 NA NA NA NA NA NA NA NA NA NA NA NA NA NA

<0.50

<1.00

< 0.02 4.60 NA NA NA NA NA NA NA 4.26 NA NA 04/07/17 NA NA NA NA NA NA NA NA NA NA NA NA NA NA

<0.50

<1.00

< 0.02

-0.376 U NA NA NA NA NA NA NA 3.96 U NA NA 07/12/17 NA NA NA NA NA NA NA NA NA NA NA NA NA NA

<0.50

<1.00 0.066 3.16 U NA NA NA NA NA NA NA 2.48 U NA NA 10/03/17 NA NA NA NA NA NA NA NA NA NA NA NA NA NA

<0.50

<1.00 0.062 1.99 U NA NA NA NA NA NA NA 4.59 NA NA 01/15/18 NA NA NA NA NA NA NA NA NA NA NA NA NA NA

<0.50

<1.00

< 0.02 2.96 NA NA NA NA NA NA NA 4.81 NA NA 04/22/18 NA NA NA NA NA NA NA NA NA NA NA NA NA NA

<0.50

<1.00

< 0.02 0.242 U NA NA NA NA NA NA NA 0.346 U NA NA 07/15/18 NA NA NA NA NA NA NA NA NA NA NA NA NA NA

<0.50

<1.00 66 1.66 U NA NA NA NA NA NA NA 3.49 U NA NA 10/29/18 NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA 0.0322

< 0.02 1.04 U NA NA NA

< 0.0500

< 0.0700

< 0.200

< 0.200 1.99 U NA NA 11/29/18

< 5.0

< 5.0

< 5.0

< 5.0

< 5.0

< 5.0

< 2.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.067 0.0241

< 0.02 0.554 U

-0.0229 U 0.0350 U 0.0298 U

< 0.0500

< 0.0700

< 0.200

< 0.200 1.86 U 18.2 U NA 01/29/19

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.038 0.028

< 0.02 0.683 U 0.118 U 0.196 U 0.0882 U

< 0.0500

< 0.0700

< 0.200

< 0.200 2.62 U

-1.12 U NA 10/10/19

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.015 0.0256

< 0.020 2.36 U 0.287 U 0.0414 U 0.145 U

< 0.050

< 0.070

< 0.200

< 0.200 1.15 U 7.25 U NA 04/27/20

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.8

< 0.8

< 4.0

< 0.8

< 0.8

< 0.80

< 0.1 0.0146

< 0.02 3.56 U 0.0204 U 0 U 0.0308 U

< 0.0500

< 0.0700 0.106 J 0.106 J 2.21 U

-0.726 U NA W-4 01/28/19

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 4.56 0.0269 8.4 1.89 U 0.541 0.318 0.101 U

< 0.0500

< 0.0700 0.143 J 0.143 J 28.6 12.4 U NA 10/11/19

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 4.86 0.404 0.023 3.36 U 0.313 0.124 U 0.392

< 0.050

< 0.070 0.146 J 0.146 J 19.4 41.3 NA 04/27/20

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.8

< 0.8

< 4.0

< 0.8

< 0.8

< 0.80 4.89 0.0225 1.4

-0.539 U 0.112 U

-0.000240 U 0.116 U

< 0.0500

< 0.0700 0.181 J 0.181 J 20.9 24.5 NA Radionuclides Inorganics MCL/Action Level VOCs SVOCs Page 1 of 20

Table C-1 Summary of Historical Groundwater Analytical Results (2015-2020)

Westinghouse Columbia Fuel Fabrication Facility Hopkins, South Carolina AECOM Project No. 60595649 Carbon Disulfide ug/L Chloroform ug/L cis-1,2-Dichloroethene ug/L Ethylbenzene ug/L Tetrachloroethene ug/L Trichloroethene ug/L Vinyl Chloride ug/L 1,1'-Biphenyl ug/L 2-Methylnaphthalene ug/L Acenaphthene ug/L Carbazole ug/L Fluorene ug/L Naphthalene ug/L Phenanthrene ug/L Fluoride mg/L Ammonia NH3(N) mg/L Nitrate NO3 mg/L Gross Alpha pCi/L Isotopic Uranium 233/234 pCi/L Isotopic Uranium 235/236 pCi/L Isotopic Uranium 238 (HASL300) pCi/L Isotopic Uranium 234 ug/L Isotopic Uranium 235 ug/L Isotopic Uranium 238 ug/L Total Uranium ug/L Gross Beta pCi/L Tc-99 pCi/L Tritium pCi/L 70 700 5

5 2

4 10 15

• 30 50

• 900 20,000 Well Date Radionuclides Inorganics MCL/Action Level VOCs SVOCs W-6 11/05/18

< 5.0

< 5.0

< 5.0

< 5.0

< 5.0

< 5.0

< 2.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.058 6.16 14 8.41 1.00 0.0392 U 0.311 U

< 0.0500 0.011 J 0.409 0.42 765 861 NA 01/15/19

< 1.0

< 1.0 1.9

< 1.0 10 1.8

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.136 60.5 150 34.6 0.397 0.153 U 0.327

< 0.0500

< 0.0700 0.2 0.2 1620 2370 NA 10/07/19

< 1.0

< 1.0 2.8

< 1.0 16 2.5

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.126 134 210 9.09 0.372 0.0443 U 0.153 U

< 0.050

< 0.070 0.232 0.232 1370 2440 NA 04/07/20

< 1.0

< 1.0 2.7

< 1.0 19 2.7

< 1.0

< 4.0

< 0.8

< 0.8

< 4.0

< 0.8

< 0.8

< 0.80 0.112 58 190 37.6 0.0213 U 0 U 0.0977 U

< 0.0500

< 0.0700 0.183 J 0.183 J 1260 2450 NA W-7A 07/08/16 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 7.30 58.50 350 0.285 U NA NA NA NA NA NA NA 149 378

-121 U 10/11/16 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 6.40 59.4 310 2.24 U NA NA NA NA NA NA NA 123 254

-28.9 U 01/17/17 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 2.06 56.8 360 15.4 0.289 U 0.246 U

-0.0394 U NA NA NA NA 125 NA 219 U 04/06/17 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 6.55 55.9 230 4.22 U NA NA NA NA NA NA NA 262 NA 42.4 U 07/10/17 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 6.80 55.7 290 19.8 1.78 0.257 U 0.828 NA NA NA NA 150 185

-109 U 10/12/17 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 6.65 61.3 360 9.10 NA NA NA NA NA NA NA 131 209

-240 U 01/08/18 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 7.15 65.7 300 9.24 NA NA NA NA NA NA NA 141 211 210 U 04/16/18 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 6.25 60.7 310 7.71 NA NA NA NA NA NA NA 124 212

-29.7 U 07/01/18 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 6.27 61 300 7.88 NA NA NA NA NA NA NA 110 139 NA 10/19/18 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 6.86 65 370 3.38 U NA NA NA

< 0.0500

< 0.0700 0.691 0.691 110 175

-24.3 U 01/14/19

< 1.0

< 1.0

< 1.0

< 1.0 1.7

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 6.6 62.5 350 6.28 U 0.559 0.207 U 0.558

< 0.0500

< 0.0700 0.719 0.719 123 160 99.7 U 06/04/19

< 1.0

< 1.0

< 1.0

< 1.0 2.1

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 6.49 65.5 350 14.5 0.378 0.0157 U 0.0818 U

< 0.0500

< 0.0700 0.812 0.812 142 176 205 U 10/09/19

< 1.0

< 1.0

< 1.0

< 1.0 1.9

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 6.47 48.5 390 6.35 0.409 0.0909 U 0.259

< 0.050

< 0.070 0.698 0.698 114 210

-16.9 U 04/10/20

< 1.0

< 1.0

< 1.0

< 1.0 1.6

< 1.0

< 1.0

< 4.0

< 0.8

< 0.8

< 4.0

< 0.8

< 0.8

< 0.80 6.04 44.6 330 1.99 U 0.240

-0.0195 U 0.219

< 0.0500

< 0.0700 0.716 0.716 54.0 180 115 U W-10 01/19/15 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 3.65 2.40 75 3.75 NA NA NA NA NA NA NA 88.3 149 U 50.6 U 04/13/15 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 2.70 4.40 66 1.66 U NA NA NA NA NA NA NA 88.8

-59.8 U 115 U 07/13/15 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 2.96 8.59 85 7.68 NA NA NA NA NA NA NA 150 172 U

-269 U 10/12/15 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 2.70 4.60 52 3.57 U NA NA NA NA NA NA NA 52.0 94.5 U 16.0 U 01/14/16 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 2.98 7.90 64 0.0550 U NA NA NA NA NA NA NA 94.1 36.9 U

-130 U 04/19/16 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 3.52 26.00 72 1.77 U NA NA NA NA NA NA NA 108 85.7 U 245 U 07/08/16 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 3.16 6.60 67 4.87 U NA NA NA NA NA NA NA 103 257 U 73.4 U 10/11/16 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 3.93 8.86 51 1.57 U NA NA NA NA NA NA NA 84.6 216

-220 U 01/17/17 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 3.15 5.02 51 6.39 NA NA NA NA NA NA NA 79.2 131 190 U 04/06/17 NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA 2.06 U NA NA NA NA NA NA NA 92.0 NA

-140 U 04/07/17 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 3.30 8.08 52 NA NA NA NA NA NA NA NA NA NA NA 07/10/17 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 3.95 8.89 41 8.39 NA NA NA NA NA NA NA 89.2 94.7 26.2 U 10/12/17

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 3.68 8.5 55 2.84 U NA NA NA NA NA NA NA 78.4 129

-215 U 01/08/18 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 3.17 3.46 46 3.71 NA NA NA NA NA NA NA 99.4 143 240 U 04/16/18 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 3.08 3.29 41 4.16 U NA NA NA NA NA NA NA 79.2 113

-94.9 U 07/13/18 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 3.04 0.988 35 1.11 U NA NA NA NA NA NA NA 65.7 129

-117 U 10/19/18

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 3.46 2.21 21 0.233 U NA NA NA

< 0.0500

< 0.0700 0.0841 J 0.0841 J 68.7 90.0 278 U 01/14/19

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 3.42 4.62 15 0.960 U 0.217 U 0.204 U 0.0620 U

< 0.0500

< 0.0700 0.0854 J 0.0854 J 50.9 80.9

-83.9 U 06/04/19

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 3.59 7.41 22 1.51 U

-0.0639 U

-0.0267 U 0.0126 U

< 0.0500

< 0.0700 0.114 J 0.114 J 66.3 88.7

-5.40 U 10/09/19

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 3.32 6.46 37 3.19 0.0993 U 0.0935 U 0.180 U

< 0.050

< 0.070 0.083 J 0.083 J 81.3 118 32.7 U 04/13/20

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.8

< 0.8

< 4.0

< 0.8

< 0.8

< 0.80 2.95 4.24 21

-0.113 U 0.0637 U 0.00902 U 0.0301 U

< 0.0500

< 0.0700

< 0.200

< 0.200 47.8 81.2 145 U W-11 11/05/18

< 5.0

< 5.0

< 5.0

< 5.0

< 5.0

< 5.0

< 2.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.01 4.59 57 7.82 0.0922 U 0 U 0.114 U

< 0.0500

< 0.0700

< 0.200

< 0.200 2160 3570 NA 12/05/18

< 5.0

< 5.0

< 5.0

< 5.0

< 5.0

< 5.0

< 2.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0

6.4 63 14.2 0.0262 U

-0.00969 U 0.110 U

< 0.0500

< 0.0700

< 0.200

< 0.200 2450 3640 NA 01/11/19

< 1.0 1.1

< 1.0

< 1.0 2

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.018 6.42 64 17.0 0.497 0.0412 U 0.256 U

< 0.0500

< 0.0700 0.192 J 0.192 J 1810 4200 NA 06/05/19

< 1.0 1.2

< 1.0

< 1.0 1.9 1.3

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.005 4.37 50 20.9 0.0194 U 0.0248 U 0.0464 U

< 0.0500

< 0.0700 0.0696 J 0.0696 J 2060 2660 NA 10/08/19

< 1.0 1.1

< 1.0

< 1.0 1.4

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.021 4.09 56 7.82 0.205 U 0.0769 U 0.133 U

< 0.050

< 0.070

< 0.200

< 0.200 2450 3420 NA 04/10/20

< 1.0 1

< 1.0

< 1.0 1.4

< 1.0

< 1.0

< 4.0

< 0.8

< 0.8

< 4.0

< 0.8

< 0.8

< 0.80 0.017 4.95 51 36.3

-0.0539 U 0.0116 U 0.00916 U

< 0.0500

< 0.0700

< 0.200

< 0.200 2080 3440 NA Page 2 of 20

Table C-1 Summary of Historical Groundwater Analytical Results (2015-2020)

Westinghouse Columbia Fuel Fabrication Facility Hopkins, South Carolina AECOM Project No. 60595649 Carbon Disulfide ug/L Chloroform ug/L cis-1,2-Dichloroethene ug/L Ethylbenzene ug/L Tetrachloroethene ug/L Trichloroethene ug/L Vinyl Chloride ug/L 1,1'-Biphenyl ug/L 2-Methylnaphthalene ug/L Acenaphthene ug/L Carbazole ug/L Fluorene ug/L Naphthalene ug/L Phenanthrene ug/L Fluoride mg/L Ammonia NH3(N) mg/L Nitrate NO3 mg/L Gross Alpha pCi/L Isotopic Uranium 233/234 pCi/L Isotopic Uranium 235/236 pCi/L Isotopic Uranium 238 (HASL300) pCi/L Isotopic Uranium 234 ug/L Isotopic Uranium 235 ug/L Isotopic Uranium 238 ug/L Total Uranium ug/L Gross Beta pCi/L Tc-99 pCi/L Tritium pCi/L 70 700 5

5 2

4 10 15

• 30 50

• 900 20,000 Well Date Radionuclides Inorganics MCL/Action Level VOCs SVOCs W-13R 01/19/15 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 10.90 44.00 30 4.48 NA NA NA NA NA NA NA 114 214 336 U 04/13/15 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 10.70 47.80 33

-0.478 U NA NA NA NA NA NA NA 143 117 U 164 U 07/13/15 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 10.70 49.10 30 1.42 U NA NA NA NA NA NA NA 37.7 72.1 U

-15.0 U 10/12/15 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 10.70 49.10 30 6.66 NA NA NA NA NA NA NA 86.2 264

-240 U 01/14/16 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 9.90 52.70 46 1.36 U NA NA NA NA NA NA NA 130 168 U

-130 U 04/19/16 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 10.00 46.60 28 2.50 NA NA NA NA NA NA NA 102 113 U 504 U 07/08/16 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 9.95 41.90 27 2.79 U NA NA NA NA NA NA NA 68.0 204 U 151 U 10/11/16 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 9.95 45.6 27 1.99 U NA NA NA NA NA NA NA 77.3 234

-206 U 01/17/17 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 9.75 44.6 28 6.14 NA NA NA NA NA NA NA 65.0 166

-108 U 04/06/17 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 10.2 44.0 29 10.5 NA NA NA NA NA NA NA 65.0 NA

-167 U 07/13/17 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 10.4 45.3 28 25.2 4.11 0.340 1.38 NA NA NA NA 73.0 147

-72.5 U 10/12/17

< 1.0

< 1.0 1.1

< 1.0 31 2.5

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 9.45 43 24 9.02 NA NA NA NA NA NA NA 52.6 96.9

-228 U 01/08/18 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 9.7 35.4 22 23.6 1.22 0.126 U 0.405 U NA NA NA NA 69.5 NA 128 U 04/20/18 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 7.95 39.9 24 9.29 NA NA NA NA NA NA NA 55.2 86.3 42.8 U 07/13/18 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 8.96 34.3 23 7.07 NA NA NA NA NA NA NA 60.9 67.2 263 U 08/30/18

< 1.0

< 1.0

< 1.0

< 1.0 25 2.1

< 1.0 NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA 10/19/18

< 1.0

< 1.0 1.4

< 1.0 39 3.1

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 8.79 38.8 24 2.06 U NA NA NA

< 0.0500

< 0.0700 0.131 J 0.131 J 97.6 149 111 U 01/10/19

< 1.0

< 1.0 1.3

< 1.0 46 3.7

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 8.29 31.8 21 0.976 U 0.191 U 0.107 U 0.210 U

< 0.0500

< 0.0700 0.149 J 0.149 J 73.5 111

-210 U 06/06/19

< 1.0

< 1.0

< 1.0

< 1.0 14 1.3

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 7.95 28.1 16 4.01 U 0.00734 U

-0.0335 U 0.0662 U

< 0.0500

< 0.0700 0.128 J 0.128 J 48.9 60.9 150 U 10/08/19

< 1.0

< 1.0

< 1.0

< 1.0 15 1.4

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 8.11 31.5 18 2.15 U 0.246 U 0.0418 U 0.221

< 0.050

< 0.070 0.139 J 0.139 J 53.2 63.4 116 U 04/08/20

< 1.0

< 1.0

< 1.0

< 1.0 14 1.3

< 1.0

< 4.0

< 0.8

< 0.8

< 4.0

< 0.8

< 0.8

< 0.80 7.07 21.4 13 3.48 U 0.0454 U

-0.000219 U 0.0527 U

< 0.0500

< 0.0700 0.076 J 0.076 J 36.0 58.9

-95.1 U W-14 01/20/15 NA NA NA NA NA NA NA NA NA NA NA NA NA NA

<0.50

<1.00 3.3

-0.167 U NA NA NA NA NA NA NA 3.56 U

-13.7 U

-45.6 U 04/14/15 NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA

-1.22 U NA NA NA NA NA NA NA 8.20

-40.3 U

-135 U 04/17/15 NA NA NA NA NA NA NA NA NA NA NA NA NA NA

<0.50

<1.00 2.4 NA NA NA NA NA NA NA NA NA NA NA 07/10/15 NA NA NA NA NA NA NA NA NA NA NA NA NA NA

<0.50 2.77 0.46 3.66 NA NA NA NA NA NA NA 14.5 40.0 U

-75.9 U 10/13/15 NA NA NA NA NA NA NA NA NA NA NA NA NA NA

<0.50

<1.00 3.4

-0.466 U NA NA NA NA NA NA NA 5.83

-27.5 U

-191 U 01/18/16 NA NA NA NA NA NA NA NA NA NA NA NA NA NA

<0.50

<1.00 2.7 1.88 U NA NA NA NA NA NA NA 1.54 U NA

-117 U 04/18/16 NA NA NA NA NA NA NA NA NA NA NA NA NA NA

<0.50 1.98 1.6 2.36 U NA NA NA NA NA NA NA 5.18 NA 58.8 U 07/12/16 NA NA NA NA NA NA NA NA NA NA NA NA NA NA

<0.50 2.26 1.9 1.31 U NA NA NA NA NA NA NA 8.10 NA NA 10/13/16 NA NA NA NA NA NA NA NA NA NA NA NA NA NA

<0.50

<1.00 3.8 1.21 U NA NA NA NA NA NA NA 1.21 U NA NA 01/13/17 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 0.00

<1.00 3.6 1.74 U NA NA NA NA NA NA NA

-0.906 U NA NA 04/05/17 NA NA NA NA NA NA NA NA NA NA NA NA NA NA

<0.50 1.79 2

2.29 NA NA NA NA NA NA NA 8.34 NA NA 07/11/17 NA NA NA NA NA NA NA NA NA NA NA NA NA NA

<0.50

<1.00 2.9 1.03 U NA NA NA NA NA NA NA 2.06 U NA NA 10/03/17 NA NA NA NA NA NA NA NA NA NA NA NA NA NA

<0.50 1.59 2.4

-0.352 U NA NA NA NA NA NA NA 8.82 NA NA 01/12/18 NA NA NA NA NA NA NA NA NA NA NA NA NA NA

<0.50

<1.00 2.7 2.82 NA NA NA NA NA NA NA 7.73 NA NA 04/17/18 NA NA NA NA NA NA NA NA NA NA NA NA NA NA

<0.50 1.6 2.3 2.42 U NA NA NA NA NA NA NA 10.0 NA NA 07/12/18 NA NA NA NA NA NA NA NA NA NA NA NA NA NA

<0.50 1.31 2.4 1.62 U NA NA NA NA NA NA NA 4.97 NA NA 08/30/18

< 1.0

< 1.0

< 1.0

< 1.0 16 2.6

< 1.0 NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA 10/18/18

< 1.0

< 1.0

< 1.0

< 1.0 35 5.3

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.025 0.175 3.3 0.0847 U NA NA NA

< 0.0500

< 0.0700

< 0.200

< 0.200 1.85 U NA NA 01/25/19

< 1.0

< 1.0

< 1.0

< 1.0 9.9 2.1

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.066 1.64 0.5 3.07 U 0.374 U 0.0801 U 0.0790 U

< 0.0500

< 0.0700 0.104 J 0.104 J 11.3 8.11 U NA 10/18/19

< 1.0

< 1.0

< 1.0

< 1.0 1.1

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.079 4.26 0.061 4.27 0.0696 U

-0.0412 U 0.139 U

< 0.050

< 0.070 0.368 0.368 35.6

-4.64 U NA 04/22/20

< 1.0

< 1.0

< 1.0

< 1.0 4.8 1.3

< 1.0

< 4.0

< 0.8

< 0.8

< 4.0

< 0.8

< 0.8

< 0.80 0.083 4.27 0.11 4.99 0.532 0.110 U 0.467

< 0.0500

< 0.0700 0.36 0.36 15.4 0.611 U NA Page 3 of 20

Table C-1 Summary of Historical Groundwater Analytical Results (2015-2020)

Westinghouse Columbia Fuel Fabrication Facility Hopkins, South Carolina AECOM Project No. 60595649 Carbon Disulfide ug/L Chloroform ug/L cis-1,2-Dichloroethene ug/L Ethylbenzene ug/L Tetrachloroethene ug/L Trichloroethene ug/L Vinyl Chloride ug/L 1,1'-Biphenyl ug/L 2-Methylnaphthalene ug/L Acenaphthene ug/L Carbazole ug/L Fluorene ug/L Naphthalene ug/L Phenanthrene ug/L Fluoride mg/L Ammonia NH3(N) mg/L Nitrate NO3 mg/L Gross Alpha pCi/L Isotopic Uranium 233/234 pCi/L Isotopic Uranium 235/236 pCi/L Isotopic Uranium 238 (HASL300) pCi/L Isotopic Uranium 234 ug/L Isotopic Uranium 235 ug/L Isotopic Uranium 238 ug/L Total Uranium ug/L Gross Beta pCi/L Tc-99 pCi/L Tritium pCi/L 70 700 5

5 2

4 10 15

• 30 50

• 900 20,000 Well Date Radionuclides Inorganics MCL/Action Level VOCs SVOCs W-15 01/20/15 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 2.22 10.10 12 4.55 NA NA NA NA NA NA NA 202 308 81.7 U 04/14/15 NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA 3.05 NA NA NA NA NA NA NA 168 242

-67.7 U 04/17/15 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 2.16 6.35 26 NA NA NA NA NA NA NA NA NA NA NA 07/10/15 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 2.40 12.60 24 1.48 U NA NA NA NA NA NA NA 199 182 U

-140 U 10/13/15 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 2.56 14.20 21 2.08 U NA NA NA NA NA NA NA 157 229 33.6 U 01/18/16 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 3.07 16.40 26 1.15 U NA NA NA NA NA NA NA 189 254 127 U 04/18/16 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 2.42 15.00 24

-0.206 U NA NA NA NA NA NA NA 178 256 156 U 07/12/16 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 2.01 13.80 26 3.80 U NA NA NA NA NA NA NA 220 445 40.3 U 10/13/16 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 1.99

<1.00 27 2.59 NA NA NA NA NA NA NA 143 371 14.7 U 01/11/17 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 1.92 15.0 28 9.76 NA NA NA NA NA NA NA 75.7 284

-53.6 U 04/05/17 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 2.06 16.3 29 8.08 NA NA NA NA NA NA NA 165 NA 346 U 07/11/17 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 2.22 14.3 29 8.24 NA NA NA NA NA NA NA 175 276

-193 U 10/13/17

< 1.0

< 1.0 2.4

< 1.0 26 3.2

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 1.88 14 27 1.41 U NA NA NA NA NA NA NA 185 295

-291 U 01/12/18 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 1.77 17.1 34 5.03 NA NA NA NA NA NA NA 174 255 99.3 U 04/17/18 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 1.67 18.2 45 8.79 NA NA NA NA NA NA NA 181 261 54.2 U 07/12/18 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 1.74 17.5 44 3.92 U NA NA NA NA NA NA NA 180 264

-2.01 U 08/30/18

< 1.0

< 1.0 1.8

< 1.0 19 2.4

< 1.0 NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA 10/17/18

< 1.0

< 1.0 1.2

< 1.0 11 2

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 1.86 13.1 44 2.19 U NA NA NA

< 0.0500

< 0.0700

< 0.200

< 0.200 195 265

-16.0 U 01/23/19

< 1.0

< 1.0

< 1.0

< 1.0 8.4 1.6

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 2.26 18.4 49 4.81 0.149 U 0.0456 U 0.111 U

< 0.0500

< 0.0700

< 0.200

< 0.200 146 233

-143 U 06/04/19

< 1.0

< 1.0 1.2

< 1.0 13 2.3

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 1.92 13.4 44 3.33 U 0.271 U 0.0242 U 0.0754 U

< 0.0500

< 0.0700 0.103 J 0.103 J 186 281

-143 U 10/21/19

< 1.0

< 1.0 1.3

< 1.0 12 2.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 1.88 12.6 35

-0.242 U 0.0108 U 0.162 U 0.0531 U

< 0.050

< 0.070

< 0.200

< 0.200 174 253

-19.1 U 04/21/20

< 1.0

< 1.0

< 1.0

< 1.0 7.2 1.4

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 2.28 14.7 36 8.12

-0.000428 U

-0.0236 U

-0.00796 U

< 0.0500

< 0.0700

< 0.200

< 0.200 114 219 50.2 U W-16 01/20/15 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 7.50 12.00 2.7 3.99 U NA NA NA NA NA NA NA 19.6

-57.0 U 337 U 04/14/15 NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA 1.16 U NA NA NA NA NA NA NA 14.1

-83.2 U 96.2 U 04/17/15 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 7.20 10.20 2.7 NA NA NA NA NA NA NA NA NA NA NA 07/10/15 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 9.55 16.20 2.6 3.59 NA NA NA NA NA NA NA 15.7

-45.4 U

-226 U 10/13/15 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 8.90 19.80 3.4 4.59 NA NA NA NA NA NA NA 21.0

-8.60 U

-77.1 U 01/18/16 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 8.40 15.20 2.7 0.0310 U NA NA NA NA NA NA NA 21.4 NA 11.8 U 04/18/16 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 8.30 16.20 2.5 4.45 U NA NA NA NA NA NA NA 19.7 NA 157 U 07/12/16 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 8.60 3.10 3.9 3.58 NA NA NA NA NA NA NA 23.5 NA 128 U 10/13/16 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 8.85 15.0 3.7 5.17 NA NA NA NA NA NA NA 21.4 NA

-104 U 01/13/17 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 8.50 15.7 2.9 7.10 NA NA NA NA NA NA NA 18.0 NA

-53.3 U 04/05/17 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 8.20 16.4 3

0.0414 U NA NA NA NA NA NA NA 13.0 NA 52.8 U 07/11/17 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 9.1 14.4 3.9 2.03 U NA NA NA NA NA NA NA 22.1 NA

-254 U 10/13/17

< 1.0

< 1.0 2.6

< 1.0 12 3

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 8.95 17.3 4.2 2.02 U NA NA NA NA NA NA NA 16.5 NA

-99.7 U 01/12/18 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 8.3 19.2 3.5 3.59 NA NA NA NA NA NA NA 19.8 NA 232 U 04/17/18 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 8.35 20.2 4.6 1.27 U NA NA NA NA NA NA NA 12.2 NA

-166 U 07/12/18 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 8.82 19.9 4.5 3.84 U NA NA NA NA NA NA NA 16.2 NA

-157 U 10/18/18

< 1.0

< 1.0 3.2

< 1.0 11 2.9

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 8.62 18.2 4.6

-1.50 U NA NA NA

< 0.0500

< 0.0700

< 0.200

< 0.200 17.2 NA

-24.6 U 01/28/19

< 1.0

< 1.0 1.2

< 1.0 6.4 1.7

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 7.61 15.3 3

5.21

-0.0436 U 0.0483 U 0.0802 U

< 0.0500

< 0.0700 0.113 J 0.113 J 15.4 4.93 U 117 U 06/04/19

< 1.0

< 1.0 1.5

< 1.0 9.6 2.4

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 8.36 17.1 3.8 3.85 U

-0.0556 U

-0.0300 U 0.0891 U

< 0.0500

< 0.0700 0.0846 J 0.0846 J 18.3 16.4 U

-201 U 10/21/19

< 1.0

< 1.0 1.5

< 1.0 7.8 2.2

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 9.5 13.3 3.2 0.421 U 0.168 U 0.0107 U 0.0718 U

< 0.050

< 0.070

< 0.200

< 0.200 10.6

-4.45 U 12.8 U 04/21/20

< 1.0

< 1.0 1.3

< 1.0 5.6 1.7

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 8.92 16 2.5 1.86 U 0.0631 U

-0.0225 U

-0.0546 U

< 0.0500

< 0.0700 0.0827 J 0.0827 J 14.4 6.84

-117 U Page 4 of 20

Table C-1 Summary of Historical Groundwater Analytical Results (2015-2020)

Westinghouse Columbia Fuel Fabrication Facility Hopkins, South Carolina AECOM Project No. 60595649 Carbon Disulfide ug/L Chloroform ug/L cis-1,2-Dichloroethene ug/L Ethylbenzene ug/L Tetrachloroethene ug/L Trichloroethene ug/L Vinyl Chloride ug/L 1,1'-Biphenyl ug/L 2-Methylnaphthalene ug/L Acenaphthene ug/L Carbazole ug/L Fluorene ug/L Naphthalene ug/L Phenanthrene ug/L Fluoride mg/L Ammonia NH3(N) mg/L Nitrate NO3 mg/L Gross Alpha pCi/L Isotopic Uranium 233/234 pCi/L Isotopic Uranium 235/236 pCi/L Isotopic Uranium 238 (HASL300) pCi/L Isotopic Uranium 234 ug/L Isotopic Uranium 235 ug/L Isotopic Uranium 238 ug/L Total Uranium ug/L Gross Beta pCi/L Tc-99 pCi/L Tritium pCi/L 70 700 5

5 2

4 10 15

• 30 50

• 900 20,000 Well Date Radionuclides Inorganics MCL/Action Level VOCs SVOCs W-17 01/20/15 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 2.02 5.89 13 1.87 NA NA NA NA NA NA NA 470 734 50.2 U 04/14/15 NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA 0.749 U NA NA NA NA NA NA NA 511 789 31.0 U 04/17/15 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 1.66 3.72 17 NA NA NA NA NA NA NA NA NA NA NA 07/15/15 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 1.98 6.14 12 1.38 U NA NA NA NA NA NA NA 477 663

-44.3 U 10/13/15 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 1.93 6.81 13 0.447 U NA NA NA NA NA NA NA 462 848

-77.4 U 01/21/16 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 1.78 5.62 15 10.2 NA NA NA NA NA NA NA 592 780

-145 U 04/21/16 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 1.52 4.39 NA 0.514 U NA NA NA NA NA NA NA 396 1410

-73.7 U 07/12/16 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 1.62 5.01 15 NA NA NA NA NA NA NA NA NA NA NA 10/13/16 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 1.47 4.55 16 NA NA NA NA NA NA NA NA NA NA NA 01/13/17 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 1.60 5.13 15 NA NA NA NA NA NA NA NA NA NA NA 04/07/17 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 14.70 4.35 16 NA NA NA NA NA NA NA NA NA NA NA 07/11/17 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 1.52 4.79 16 NA NA NA NA NA NA NA NA NA NA NA 10/02/17 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 1.56 4.79 16 NA NA NA NA NA NA NA NA NA NA NA 01/15/18 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 1.44 4.54 18 NA NA NA NA NA NA NA NA NA NA NA 04/20/18 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 1.55 5.35 16 NA NA NA NA NA NA NA NA NA NA NA 07/12/18 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 1.7 5.01 14 NA NA NA NA NA NA NA NA NA NA NA 10/25/18

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 4.02 12.9 4.5

-1.66 U NA NA NA

< 0.0500

< 0.0700 0.157 J 0.157 J 254 348 NA 01/25/19

< 1.0

< 1.0

< 1.0

< 1.0 1.7

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 2.44 5.58 12 0.705 U 0.121 U 0.146 U 0.107 U

< 0.0500

< 0.0700 0.0939 J 0.0939 J 308 476 NA 10/21/19

< 1.0

< 1.0

< 1.0

< 1.0 4.3

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 2.22 5.79 16 2.86 U 0.209 U 0.0726 U 0.0507 U

< 0.050

< 0.070 0.0855 J 0.0855 J 538 820 NA 04/20/20

< 1.0

< 1.0

< 1.0

< 1.0 2

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 2.55 8.97 13 15.5 0.249 U 0 U

-0.0261 U

< 0.0500

< 0.0700 0.121 J 0.121 J 210 429 NA W-18R 07/08/16 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 6.40 122.00 890.00 2.62 U NA NA NA NA NA NA NA 228 551 212 U 10/21/16 NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA 9.55 U 2.76 0.301 2.34 NA NA NA NA 157 314

-15.7 U 10/24/16 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 6.53 135 1100 NA NA NA NA NA NA NA NA NA NA 01/16/17 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 6.30 117 940 21.4 3.45 0.139 U 2.57 NA NA NA NA 207 NA 27.3 U 04/06/17 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 5.60 113 720 1.50 U 5.17 0.328 U 2.46 NA NA NA NA 153 NA

-125 U 07/10/17 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 6.70 132 980 21.2 3.78 0.438 U 3.09 NA NA NA NA 191 355

-206 U 01/08/18 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 6.2 127 900 18.9 4.20 0.446 2.24 NA NA NA NA 183 NA 368 U 04/16/18 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 6.25 122 930 26.5 3.89 0.325 U 2.25 NA NA NA NA 211 NA

-8.36 U 07/13/18 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 6.37 123 840 9.77 NA NA NA NA NA NA NA 172 384 217 U 10/23/18

< 1.0 1.6

< 1.0

< 1.0 2.8

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 4.8 86.5 710 14.3 1.85 0.247 U 1.19

< 0.0500 0.0453 J 4.42 4.47 131 208 14.9 U 01/15/19

< 1.0 1.4

< 1.0

< 1.0 2.2

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 5.56 95 750 6.79 U 4.62 0.528 2.07

< 0.0500 0.062 J 5.03 5.09 124 168

-176 U 10/07/19

< 1.0 1.9

< 1.0

< 1.0 3.5

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 6.34 126 770 9.79 U 1.53 0.266 1.17

< 0.050 0.035 J 4.06 4.1 150 214 210 U 04/07/20

< 1.0 1.4

< 1.0

< 1.0 3.4

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 4.6 55 790 8.00 U 2.12 0.0757 U 1.41

< 0.0500 0.05 J 4.32 4.37 73.6 295

-11.8 U W-19B 08/30/18

< 1.0

< 1.0

< 1.0

< 1.0 110 2.2

< 1.0 NA NA NA NA NA NA NA NA NA 4.1 1.32 U NA NA NA NA NA NA NA 3.45 NA 348 U 10/03/18

< 1.0

< 1.0

< 1.0

< 1.0 83 1.7

< 1.0 NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA 10/04/18 NA NA NA NA NA NA NA

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 11/04/18

< 5.0

< 5.0

< 5.0

< 5.0 120

< 5.0

< 2.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.016 0.0202 4.3

-0.816 U 0.131 U 0.0261 U 0.0423 U

< 0.0500

< 0.0700

< 0.200

< 0.200

-0.186 U

-16.0 U NA 01/23/19

< 1.0

< 1.0

< 1.0

< 1.0 92 1.9

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.024 0.0839 3.8 4.23 0.525 0.138 0.297

< 0.0500

< 0.0700

< 0.200

< 0.200 0.0395 U

-16.6 U NA 10/21/19

< 1.0

< 1.0

< 1.0

< 1.0 150 2.5

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.019 0.0146 3.8 2.26 U 0.197 U 0.125 U 0.0559 U

< 0.050

< 0.070

< 0.200

< 0.200

-0.0894 U

-3.26 U NA 04/17/20

< 1.0

< 1.0

< 1.0

< 1.0 130 2.3

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.01 0.0168 4.2 1.20 U

-0.165 U 0.0238 U

-0.133 U

< 0.0500

< 0.0700

< 0.200

< 0.200 4.24 U

-1.67 U NA Page 5 of 20

Table C-1 Summary of Historical Groundwater Analytical Results (2015-2020)

Westinghouse Columbia Fuel Fabrication Facility Hopkins, South Carolina AECOM Project No. 60595649 Carbon Disulfide ug/L Chloroform ug/L cis-1,2-Dichloroethene ug/L Ethylbenzene ug/L Tetrachloroethene ug/L Trichloroethene ug/L Vinyl Chloride ug/L 1,1'-Biphenyl ug/L 2-Methylnaphthalene ug/L Acenaphthene ug/L Carbazole ug/L Fluorene ug/L Naphthalene ug/L Phenanthrene ug/L Fluoride mg/L Ammonia NH3(N) mg/L Nitrate NO3 mg/L Gross Alpha pCi/L Isotopic Uranium 233/234 pCi/L Isotopic Uranium 235/236 pCi/L Isotopic Uranium 238 (HASL300) pCi/L Isotopic Uranium 234 ug/L Isotopic Uranium 235 ug/L Isotopic Uranium 238 ug/L Total Uranium ug/L Gross Beta pCi/L Tc-99 pCi/L Tritium pCi/L 70 700 5

5 2

4 10 15

• 30 50

• 900 20,000 Well Date Radionuclides Inorganics MCL/Action Level VOCs SVOCs W-20 01/21/15 NA NA NA NA NA NA NA NA NA NA NA NA NA NA

<0.50

<1.00 0.058 0.369 U NA NA NA NA NA NA NA 0.724 U 5.19 U 19.2 U 04/16/15 NA NA NA NA NA NA NA NA NA NA NA NA NA NA

<0.50

<1.00 0.051

-0.0909 U NA NA NA NA NA NA NA 2.04 U

-67.1 U 306 U 07/16/15 NA NA NA NA NA NA NA NA NA NA NA NA NA NA

<0.50

<1.00 0.024 0.255 U NA NA NA NA NA NA NA 1.72 U 32.4 U 19.7 U 10/19/15 NA NA NA NA NA NA NA NA NA NA NA NA NA NA

<0.50

<1.00 0.042 0.851 U NA NA NA NA NA NA NA 2.60 U 4.11 U

-32.8 U 01/20/16 NA NA NA NA NA NA NA NA NA NA NA NA NA NA

<0.50

<1.00 0.068 0.599 U NA NA NA NA NA NA NA 2.12 U NA 312 U 04/21/16 NA NA NA NA NA NA NA NA NA NA NA NA NA NA

<0.50

<1.00 0.16 0.491 U NA NA NA NA NA NA NA 2.16 U NA 54.4 U 07/13/16 NA NA NA NA NA NA NA NA NA NA NA NA NA NA

<0.50

<1.00 0.1 1.66 U NA NA NA NA NA NA NA 1.82 U NA NA 10/18/16 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 0.00

<1.00 0.032 0.0259 U NA NA NA NA NA NA NA 1.42 U NA NA 01/16/17 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 0.00

<1.00

< 0.02 3.15 U NA NA NA NA NA NA NA 1.79 U NA NA 04/05/17 NA NA NA NA NA NA NA NA NA NA NA NA NA NA

<0.50

<1.00 0.025 1.79 NA NA NA NA NA NA NA 3.32 NA NA 07/12/17 NA NA NA NA NA NA NA NA NA NA NA NA NA NA

<0.50

<1.00 0.13 8.69 NA NA NA NA NA NA NA 3.25 NA NA 10/03/17 NA NA NA NA NA NA NA NA NA NA NA NA NA NA

<0.50

<1.00 0.12 2.64 U NA NA NA NA NA NA NA 6.07 NA NA 01/15/18 NA NA NA NA NA NA NA NA NA NA NA NA NA NA

<0.50

<1.00 0.051 1.59 NA NA NA NA NA NA NA 4.16 NA NA 04/22/18 NA NA NA NA NA NA NA NA NA NA NA NA NA NA

<0.50

<1.00 0.065 1.25 U NA NA NA NA NA NA NA 4.34 U NA NA 07/15/18 NA NA NA NA NA NA NA NA NA NA NA NA NA NA

<0.50

<1.00 0.049 1.39 NA NA NA NA NA NA NA 0.644 U NA NA 08/30/18

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0 NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA 10/30/18

< 5.0

< 5.0

< 5.0

< 5.0

< 5.0

< 5.0

< 2.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.053 0.027

< 0.02

-0.639 U NA NA NA

< 0.0500

< 0.0700

< 0.200

< 0.200 1.34 U NA NA 01/29/19

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.049 0.0396 0.035 0.702 U 0.0829 U 0.0526 U 0.196 U

< 0.0500

< 0.0700

< 0.200

< 0.200 1.00 U

-8.35 U NA 10/15/19

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.077 0.0632

< 0.020 0.912 U 0.0228 U 0.0276 U 0.0995 U

< 0.050

< 0.070

< 0.200

< 0.200 3.22 U

-5.36 U NA 04/27/20

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.03 0.0266 0.045 1.35 U

-0.0101 U 0.00993 U 0.0323 U

< 0.0500

< 0.0700

< 0.200

< 0.200 3.53 U

-0.189 U NA W-22 01/19/15 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 5.50 26.10 64 7.25 NA NA NA NA NA NA NA 48.1 29.0 U 175 U 04/13/15 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 6.25 21.90 150 2.10 U NA NA NA NA NA NA NA 37.4 4.10 U

-67.3 U 07/13/15 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 6.60 63.10 170 5.75 NA NA NA NA NA NA NA 42.5 4.39 U

-236 U 10/12/15 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 4.16 14.60 30 2.07 U NA NA NA NA NA NA NA 20.3 101 U

-19.8 U 01/14/16 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 6.35 34.40 250 0.0773 U NA NA NA NA NA NA NA 40.6 NA 242 U 04/19/16 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 7.35 31.30 120

-0.490 U NA NA NA NA NA NA NA 42.3 NA 116 U 07/08/16 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 7.25 55.80 160 1.85 U NA NA NA NA NA NA NA 51.1 168 U 61.4 U 10/11/16 NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA 48 NA NA NA NA NA NA NA NA NA NA NA 10/21/16 NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA 3.77 U NA NA NA NA NA NA NA 59.0 105

-73.5 U 10/24/16 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 4.62 39.1 180 NA NA NA NA NA NA NA NA NA NA NA 01/16/17 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 5.30 22.5 110 26.8 5.20 0.251 U 1.79 NA NA NA NA 130 NA 41.7 U 04/06/17 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 6.65 64.5 300 10.2 NA NA NA NA NA NA NA 79.9 NA 109 U 07/10/17 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 6.55 33.9 96 10.1 NA NA NA NA NA NA NA 77.4 98.7

-48.3 U 10/12/17

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 6.7 72.9 140 8.32 NA NA NA NA NA NA NA 73.7 129

-216 U 01/08/18 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 5.95 67.8 130 9.93 NA NA NA NA NA NA NA 106 140 87.8 U 04/16/18 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 6.15 56.3 150 9.77 NA NA NA NA NA NA NA 92.3 128

-94.4 U 07/13/18 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 6.01 41.7 85 14.2 NA NA NA NA NA NA NA 77.9 110 321 U 10/23/18

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 4.59 35.1 71 1.34 U NA NA NA

< 0.0500 0.0128 J 0.698 0.711 17.1 NA 74.3 U 01/15/19

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 5.16 27.4 59 NA NA NA NA NA NA NA NA NA NA NA 01/22/19 NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA 4.16 U 1.18 0.437 0.672

< 0.0500 0.0138 J 0.696 0.71 18.2 14.9 U

-131 U 10/07/19

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 5.52 61.8 100 2.92 U 0.905 0.136 U 0.322

< 0.050 0.0177 J 0.854 0.872 29.6 57.4 115 U 04/07/20

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 3.63 16 50 3.52 0.420 0.0932 U 0.124 U

< 0.0500 0.0108 J 0.599 0.61 14.9 20.1 62.4 U Page 6 of 20

Table C-1 Summary of Historical Groundwater Analytical Results (2015-2020)

Westinghouse Columbia Fuel Fabrication Facility Hopkins, South Carolina AECOM Project No. 60595649 Carbon Disulfide ug/L Chloroform ug/L cis-1,2-Dichloroethene ug/L Ethylbenzene ug/L Tetrachloroethene ug/L Trichloroethene ug/L Vinyl Chloride ug/L 1,1'-Biphenyl ug/L 2-Methylnaphthalene ug/L Acenaphthene ug/L Carbazole ug/L Fluorene ug/L Naphthalene ug/L Phenanthrene ug/L Fluoride mg/L Ammonia NH3(N) mg/L Nitrate NO3 mg/L Gross Alpha pCi/L Isotopic Uranium 233/234 pCi/L Isotopic Uranium 235/236 pCi/L Isotopic Uranium 238 (HASL300) pCi/L Isotopic Uranium 234 ug/L Isotopic Uranium 235 ug/L Isotopic Uranium 238 ug/L Total Uranium ug/L Gross Beta pCi/L Tc-99 pCi/L Tritium pCi/L 70 700 5

5 2

4 10 15

• 30 50

• 900 20,000 Well Date Radionuclides Inorganics MCL/Action Level VOCs SVOCs W-23R 01/20/15 NA NA NA NA NA NA NA NA NA NA NA NA NA NA

<0.50

<1.00 0.31 1.29 U NA NA NA NA NA NA NA 0.302 U 5.46 U 81.7 U 04/14/15 NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA 1.18 U NA NA NA NA NA NA NA 0.462 U

-66.6 U

-101 U 04/17/15 NA NA NA NA NA NA NA NA NA NA NA NA NA NA

<0.50

<1.00 0.55 NA NA NA NA NA NA NA NA NA NA NA 07/10/15 NA NA NA NA NA NA NA NA NA NA NA NA NA NA

<0.50

<1.00 0.5 0.134 U NA NA NA NA NA NA NA 3.59 U 113 U

-205 U 10/13/15 NA NA NA NA NA NA NA NA NA NA NA NA NA NA

<0.50

<1.00 0.43

-0.400 U NA NA NA NA NA NA NA 0.0623 U 12.8 U

-145 U 01/18/16 NA NA NA NA NA NA NA NA NA NA NA NA NA NA

<0.50

<1.00 0.74 0.645 U NA NA NA NA NA NA NA 2.52 U NA 182 U 04/18/16 NA NA NA NA NA NA NA NA NA NA NA NA NA NA

<0.50

<1.00 0.88 0.907 U NA NA NA NA NA NA NA 0.989 U NA 243 U 07/12/16 NA NA NA NA NA NA NA NA NA NA NA NA NA NA

<0.50

<1.00 0.92 3.00 U NA NA NA NA NA NA NA 0.932 U NA NA 10/13/16 NA NA NA NA NA NA NA NA NA NA NA NA NA NA

<0.50

<1.00 1.2 16.5 1.01 0.0651 U 0.366 U NA NA NA NA 9.32 NA NA 01/13/17 NA NA NA NA NA NA NA NA NA NA NA NA NA NA

<0.50

<1.00 0.45 42.2 0.651 0.213 U 0.618 NA NA NA NA 13.3 NA NA 04/05/17 NA NA NA NA NA NA NA NA NA NA NA NA NA NA

<0.50

<1.00 0.43 4.13 NA NA NA NA NA NA NA 3.22 NA NA 07/11/17 NA NA NA NA NA NA NA NA NA NA NA NA NA NA

<0.50

<1.00 1

18.1 1.43 0.228 U 1.13 NA NA NA NA 7.19 NA NA 10/03/17 NA NA NA NA NA NA NA NA NA NA NA NA NA NA

<0.50

<1.00 0.77 8.15 NA NA NA NA NA NA NA 7.45 NA NA 01/12/18 NA NA NA NA NA NA NA NA NA NA NA NA NA NA

<0.50

<1.00 0.49 23.7 0.670 U 0.451 U 0.181 U NA NA NA NA 18.5 NA NA 04/17/18 NA NA NA NA NA NA NA NA NA NA NA NA NA NA

<0.50

<1.00 0.45 10.9 NA NA NA NA NA NA NA 8.33 NA NA 07/12/18 NA NA NA NA NA NA NA NA NA NA NA NA NA NA

<0.50

<1.00 0.19 20.7 1.02 0.591 0.801 NA NA NA NA 12.6 NA NA 08/30/18

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0 NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA 10/18/18 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 0.14 0.06 NA 0.712 U NA NA NA

< 0.0500

< 0.0700

< 0.200

< 0.200 0.307 U NA NA 01/28/19

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.01 0.02 1.2 2.60 U 0.150 U 0.0640 U 0.113 U

< 0.0500

< 0.0700

< 0.200

< 0.200 3.15 U

-3.37 U NA 10/18/19

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.017 0.0154 0.71

-0.743 U 0.0833 U

-0.0126 U 0.0221 U

< 0.050

< 0.070

< 0.200

< 0.200 1.68 U

-5.85 U NA 04/21/20

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.022 0.0292 0.88 0.307 U

-0.0211 U 0.0770 U 0.0184 U

< 0.0500

< 0.0700

< 0.200

< 0.200 2.18 U

-0.809 U NA W-24 01/20/15 NA NA NA NA NA NA NA NA NA NA NA NA NA NA

<0.50

<1.00 0.058 1.08 U NA NA NA NA NA NA NA 2.53 U 27.4 U 164 U 04/14/15 NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA 0.763 U NA NA NA NA NA NA NA 13.0

-118 U

-101 U 04/16/15 NA NA NA NA NA NA NA NA NA NA NA NA NA NA

<0.50

<1.00 0.054 NA NA NA NA NA NA NA NA NA NA NA 07/10/15 NA NA NA NA NA NA NA NA NA NA NA NA NA NA

<0.50

<1.00 0.024 0.712 U NA NA NA NA NA NA NA 1.97 U

-30.6 U

-300 U 10/09/15 NA NA NA NA NA NA NA NA NA NA NA NA NA NA

<0.50

<1.00 0.025

-0.0495 U NA NA NA NA NA NA NA 2.43 U 18.7 U

-208 U 01/15/16 NA NA NA NA NA NA NA NA NA NA NA NA NA NA

<0.50

<1.00 0.11 0.618 U NA NA NA NA NA NA NA 0.331 U NA

-17.0 U 04/18/16 NA NA NA NA NA NA NA NA NA NA NA NA NA NA

<0.50

<1.00 0.19

-0.219 U NA NA NA NA NA NA NA 1.72 U NA 42.8 U 07/05/16 NA NA NA NA NA NA NA NA NA NA NA NA NA NA

<0.50

<1.00 0.24 1.37 U NA NA NA NA NA NA NA 4.16 NA 288 U 10/13/16 NA NA NA NA NA NA NA NA NA NA NA NA NA NA

<0.50

<1.00 0.045 11.2 NA NA NA NA NA NA NA 5.45 NA

-104 U 01/11/17 NA NA NA NA NA NA NA NA NA NA NA NA NA NA

<0.50

<1.00 0.074 1.56 U NA NA NA NA NA NA NA 1.70 U NA

-137 U 04/03/17 NA NA NA NA NA NA NA NA NA NA NA NA NA NA

<0.50

<1.00 0.025 4.45 NA NA NA NA NA NA NA 2.59 NA

-0.111 U 07/11/17 NA NA NA NA NA NA NA NA NA NA NA NA NA NA

<0.50

<1.00 0.12 10.1 NA NA NA NA NA NA NA 7.70 NA

-327 U 10/13/17

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80

<0.50

<1.00 0.11 0.786 U NA NA NA NA NA NA NA 2.98 NA

-228 U 01/12/18 NA NA NA NA NA NA NA NA NA NA NA NA NA NA

<0.50

<1.00

< 0.02 7.44 NA NA NA NA NA NA NA 6.88 NA 56.8 U 04/17/18 NA NA NA NA NA NA NA NA NA NA NA NA NA NA

<0.50

<1.00 0.033 4.84 NA NA NA NA NA NA NA 2.24 U NA

-48.1 U 07/10/18 NA NA NA NA NA NA NA NA NA NA NA NA NA NA

<0.50

<1.00 0.02 4.43 NA NA NA NA NA NA NA 3.18 U NA

-14.0 U 10/16/18

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.025 0.0182 0.042 0.270 U NA NA NA

< 0.0500

< 0.0700

< 0.200

< 0.200 0.398 U NA 65.7 U 01/25/19

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.026 0.0207 0.13

-0.672 U 0.128 U 0.0898 U 0.0983 U

< 0.0500

< 0.0700

< 0.200

< 0.200 0.517 U

-3.13 U

-270 U 10/11/19

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.025 0.0283

< 0.020

-0.396 U 0.136 U 0.0816 U 0.0660 U

< 0.050

< 0.070

< 0.200

< 0.200 2.51 U 13.0 U 67.8 U 04/22/20

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.024 0.0313

< 0.02 0.684 U 0.0281 U 0.0190 U

-0.00815 U

< 0.0500

< 0.0700

< 0.200

< 0.200 4.54 0.432 U

-183 U W-25 01/30/19

< 5.0

< 5.0

< 5.0

< 5.0

< 5.0

< 5.0

< 5.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.101 1.14

< 0.02 3.58 U 0.640 0.0794 U 0.466

< 0.0500

< 0.0700 0.419 0.419 5.32

-9.45 U NA 10/16/19

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.126 1.91 0.067 10.1 0.195 U 0.0748 U 0.269

< 0.050

< 0.070 0.295 0.295 7.27

-30.7 U NA 04/27/20

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.106 0.715

< 0.02 0.271 U

-0.0246 U

-0.0124 U

-0.0306 U

< 0.0500

< 0.0700 0.0841 J 0.0841 J 2.82 U

-1.90 U NA Page 7 of 20

Table C-1 Summary of Historical Groundwater Analytical Results (2015-2020)

Westinghouse Columbia Fuel Fabrication Facility Hopkins, South Carolina AECOM Project No. 60595649 Carbon Disulfide ug/L Chloroform ug/L cis-1,2-Dichloroethene ug/L Ethylbenzene ug/L Tetrachloroethene ug/L Trichloroethene ug/L Vinyl Chloride ug/L 1,1'-Biphenyl ug/L 2-Methylnaphthalene ug/L Acenaphthene ug/L Carbazole ug/L Fluorene ug/L Naphthalene ug/L Phenanthrene ug/L Fluoride mg/L Ammonia NH3(N) mg/L Nitrate NO3 mg/L Gross Alpha pCi/L Isotopic Uranium 233/234 pCi/L Isotopic Uranium 235/236 pCi/L Isotopic Uranium 238 (HASL300) pCi/L Isotopic Uranium 234 ug/L Isotopic Uranium 235 ug/L Isotopic Uranium 238 ug/L Total Uranium ug/L Gross Beta pCi/L Tc-99 pCi/L Tritium pCi/L 70 700 5

5 2

4 10 15

• 30 50

• 900 20,000 Well Date Radionuclides Inorganics MCL/Action Level VOCs SVOCs W-26 01/12/15

< 1.0

< 1.0 1.1

< 1.0

< 1.0

< 1.0

< 2.0

< 5.2

< 5.2

< 5.2

< 5.2

< 5.2

< 5.2

< 5.2 1.83

<1.00 2.9

-0.189 U NA NA NA NA NA NA NA 11.6

-39.8 U 4.07 U 04/09/15

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 5.0

< 5.0

< 5.0

< 5.0

< 5.0

< 5.0

< 5.0 1.60

<1.00 2.9 0.569 U NA NA NA NA NA NA NA

-0.492 U 38.7 U 18.6 U 07/10/15

< 1.0

< 1.0 1

< 1.0

< 1.0

< 1.0

< 1.0

< 5.0

< 5.0

< 5.0

< 5.0

< 5.0

< 5.0

< 5.0 1.82

<1.00 2.7 1.12 U NA NA NA NA NA NA NA 12.5

-14.9 U

-108 U 10/09/15

< 1.0

< 1.0 1.8

< 1.0

< 1.0

< 1.0

< 1.0

< 5.0

< 5.0

< 5.0

< 5.0

< 5.0

< 5.0

< 5.0 1.76

<1.00 2.7 1.03 U NA NA NA NA NA NA NA 7.90 83.8 U

-115 U 01/20/16

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 5.0

< 5.0

< 5.0

< 5.0

< 5.0

< 5.0

< 5.0 1.52

<1.00 3

-1.44 U NA NA NA NA NA NA NA 12.5 NA

-29.4 U 04/18/16

< 1.0

< 1.0 1.6

< 1.0

< 1.0

< 1.0

< 1.0

< 5.0

< 5.0

< 5.0

< 5.0

< 5.0

< 5.0

< 5.0 1.44

<1.00 2.8

-0.0962 U NA NA NA NA NA NA NA 8.00 NA

-16.2 U 07/05/16

< 1.0

< 1.0 2.8

< 1.0

< 1.0

< 1.0

< 2.0

< 5.3

< 5.3

< 5.3

< 5.3

< 5.3

< 5.3

< 5.3 1.58

<1.00 2.7 0.234 U NA NA NA NA NA NA NA 7.29 NA

-52.5 U 10/06/16

< 1.0

< 1.0 2.5

< 1.0

< 1.0

< 1.0

< 2.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 1.60

<1.00 3.3

-1.63 U NA NA NA NA NA NA NA 5.66 NA

-161 U 01/10/17

< 1.0

< 1.0 3.5

< 1.0

< 1.0

< 1.0

< 2.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 1.53

<1.00 3.3 2.70 U NA NA NA NA NA NA NA 9.84 NA 15.0 U 04/03/17

< 1.0

< 1.0 1.7

< 1.0

< 1.0

< 1.0

< 2.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 1.41

<1.00 3.1 1.07 U NA NA NA NA NA NA NA 8.46 NA

-98.1 U 07/06/17

< 1.0

< 1.0 1.7

< 1.0

< 1.0

< 1.0

< 2.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 1.57

<1.00 3.4 1.92 U NA NA NA NA NA NA NA 11.7 NA

-193 U 10/13/17

< 1.0

< 1.0 4.1

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 1.57

<1.00 3

9.17 NA NA NA NA NA NA NA 16.4 NA

-353 U 01/09/18

< 1.0

< 1.0 2.8

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 1.61

<1.00 2.9 4.13 NA NA NA NA NA NA NA 15.6 NA 64.4 U 04/10/18

< 1.0

< 1.0 1.8

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 1.71

<1.00 3.6 4.12 U NA NA NA NA NA NA NA 12.7 NA

-11.4 U 07/10/18

< 1.0

< 1.0 1.6

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 1.64 0.964 3.6 1.19 U NA NA NA NA NA NA NA 6.87 NA 12.7 U 10/16/18

< 1.0

< 1.0 1.1

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 1.63 1.24 3.5 1.81 U NA NA NA

< 0.0500

< 0.0700 0.0947 J 0.0947 J 12.5 NA

-30.6 U 01/24/19

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 1.59 1.53 3.3 0.261 U 0.123 U 0.0886 U 0.0636 U

< 0.0500

< 0.0700

< 0.200

< 0.200 13.4 19.0 U 116 U 10/14/19

< 1.0

< 1.0 3.7

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 1.42 1.75 3.2 0.697 U 0.0497 U 0.0344 U 0.0381 U

< 0.050

< 0.070

< 0.200

< 0.200 12.5

-19.6 U 38.6 U 04/16/20

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 1.53 1.54 2.5 0.249 U 0.0815 U

-0.0104 U 0.0450 U

< 0.0500

< 0.0700

< 0.200

< 0.200 9.39 6.84

-29.4 U W-27 01/21/15 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 7.20 6.41

< 0.02 4.42 U NA NA NA NA NA NA NA 10.8 63.0 U 432 U 04/16/15 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 7.15 7.59

< 0.02 3.42 U NA NA NA NA NA NA NA 16.1 16.9 U

-152 U 07/16/15 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 7.05 7.88

< 0.02 2.43 U NA NA NA NA NA NA NA 5.42 26.1 U 20.2 U 10/14/15 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 7.30 9.73

< 0.02 2.17 U NA NA NA NA NA NA NA 8.67 66.9 U

-95.6 U 01/20/16 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 6.70 8.87 0.024

-0.880 U NA NA NA NA NA NA NA 6.83 NA 97.5 U 04/21/16 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 6.10 9.43

< 0.02 5.53 NA NA NA NA NA NA NA 8.52 NA

-129 U 07/13/16 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 5.55 6.73 0.11 1.55 U NA NA NA NA NA NA NA 5.46 NA NA 10/18/16 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 5.15 8.23 0.11 1.41 U NA NA NA NA NA NA NA 6.85 NA NA 01/16/17 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 5.15 7.09 0.031 7.73 NA NA NA NA NA NA NA 8.28 NA NA 04/07/17 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 4.83 7.95 0.042 5.58 NA NA NA NA NA NA NA 9.02 NA NA 07/12/17 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 5.80 7.89 0.068 5.07 NA NA NA NA NA NA NA 8.19 NA NA 10/03/17 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 4.76 7.58 0.068 10.1 NA NA NA NA NA NA NA 7.12 NA NA 01/15/18 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 4.45 6.78 0.028 5.37 NA NA NA NA NA NA NA 14.3 NA NA 04/22/18 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 4.22 6.56 0.086 3.77 U NA NA NA NA NA NA NA 8.28 NA NA 07/15/18 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 4.13 7.38

< 0.02

-0.170 U NA NA NA NA NA NA NA 10.2 NA NA 08/30/18

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0 NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA 10/29/18

< 5.0

< 5.0

< 5.0

< 5.0

< 5.0

< 5.0

< 2.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 4.47 7.99 0.027 0.185 U NA NA NA

< 0.0500

< 0.0700

< 0.200

< 0.200 7.06 NA NA 11/28/18

< 5.0

< 5.0

< 5.0

< 5.0

< 5.0

< 5.0

< 2.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 4.65 8.43 0.037 4.78 0.0358 U 0.0117 U 0.00136 U

< 0.0500

< 0.0700

< 0.200

< 0.200 9.11 14.1 U NA 01/29/19

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 4.33 6.96 0.029 1.31 U 0.168 U 0.0442 U 0.107 U

< 0.0500

< 0.0700

< 0.200

< 0.200 6.18 17.3 U NA 10/10/19

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 3.97 6.29

< 0.020

-0.689 U 0.0588 U 0.198 0.171 U

< 0.050

< 0.070

< 0.200

< 0.200 5.10 2.42 U NA 04/27/20

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 4.02 6.81 0.076 3.64 U 0.00249 U 0.0456 U

-0.0652 U

< 0.0500

< 0.0700

< 0.200

< 0.200 10.9 3.23 U NA Page 8 of 20

Table C-1 Summary of Historical Groundwater Analytical Results (2015-2020)

Westinghouse Columbia Fuel Fabrication Facility Hopkins, South Carolina AECOM Project No. 60595649 Carbon Disulfide ug/L Chloroform ug/L cis-1,2-Dichloroethene ug/L Ethylbenzene ug/L Tetrachloroethene ug/L Trichloroethene ug/L Vinyl Chloride ug/L 1,1'-Biphenyl ug/L 2-Methylnaphthalene ug/L Acenaphthene ug/L Carbazole ug/L Fluorene ug/L Naphthalene ug/L Phenanthrene ug/L Fluoride mg/L Ammonia NH3(N) mg/L Nitrate NO3 mg/L Gross Alpha pCi/L Isotopic Uranium 233/234 pCi/L Isotopic Uranium 235/236 pCi/L Isotopic Uranium 238 (HASL300) pCi/L Isotopic Uranium 234 ug/L Isotopic Uranium 235 ug/L Isotopic Uranium 238 ug/L Total Uranium ug/L Gross Beta pCi/L Tc-99 pCi/L Tritium pCi/L 70 700 5

5 2

4 10 15

• 30 50

• 900 20,000 Well Date Radionuclides Inorganics MCL/Action Level VOCs SVOCs W-28 01/19/15 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 5.35 1.76 1.4 13.4 NA NA NA NA NA NA NA 43.4

-8.87 U NA 01/29/15 NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA 330 U 04/13/15 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 6.00 1.11 5.1 3.15 U NA NA NA NA NA NA NA 33.9 82.5 U

-128 U 07/13/15 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 6.00 1.10 5.2 3.93 NA NA NA NA NA NA NA 19.9

-123 U 129 U 10/12/15 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 5.65

<1.00 5.3 4.19 U NA NA NA NA NA NA NA 14.1 44.5 U

-102 U 01/14/16 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 6.25 1.46 3.5

-0.398 U NA NA NA NA NA NA NA 15.4 NA 128 U 04/19/16 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 5.90 1.61 1.7 5.52 NA NA NA NA NA NA NA 17.7 NA

-198 U 07/08/16 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 5.95 1.51 2.4 NA NA NA NA NA NA NA NA NA NA NA 10/11/16 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 5.75

<1.00 3.6 NA NA NA NA NA NA NA NA NA NA NA 01/17/17 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 5.80

<1.00 6.3 NA NA NA NA NA NA NA NA NA NA NA 04/06/17 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 5.95

<1.00 5.7 NA NA NA NA NA NA NA NA NA NA NA 07/10/17 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 5.95 1.63 6.7 NA NA NA NA NA NA NA NA NA NA NA 10/02/17 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 5.8 1.1 5.3 NA NA NA NA NA NA NA NA NA NA NA 01/08/18 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 4.32

<1.00 6.3 NA NA NA NA NA NA NA NA NA NA NA 04/20/18 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 5.25 1.61 5.9 NA NA NA NA NA NA NA NA NA NA NA 07/13/18 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 4.65 0.938 6.2 8.02 NA NA NA NA NA NA NA 12.4 NA NA 10/23/18 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 4.63 0.721 NA 1.26 U NA NA NA

< 0.0500 0.0106 J 0.531 0.541 7.30 NA NA 01/18/19

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 5.16 0.442 7.2

-0.560 U 0.369 0.0893 U 0.146 U

< 0.0500

< 0.0700 0.456 0.456 7.28

-4.08 U NA 04/16/19

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 4.53 0.307 7.4 4.36 U 0.875 0.0810 U 0.176 U

< 0.0500 0.013 J 0.491 0.504 7.69 6.77 U NA 07/11/19

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 NA NA 7.4 2.25 U 0.806 0.00224 U 0.295

< 0.0500 0.0117 J 0.573 0.585 8.47 7.91 U NA 10/07/19

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 5.45 0.884 6.3 3.14 U 0.672 0 U 0.119 U

< 0.050

< 0.070 0.429 0.429 8.26 20.1 U NA 02/04/20

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 NA NA 8

NA NA NA NA NA NA NA NA NA NA NA 02/04/20

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 6.55 0.032 8

< 5.00 0.828

< 0.500

< 0.500

< 0.0500 0.0101 J 0.546 0.556 6.09

< 5.00 NA 04/03/20

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 5.43 0.0355 7

1.78 U 0.665

-0.0112 U 0.0287 U

< 0.0500 0.0136 J 0.696 0.71 3.86

-0.551 U NA 07/13/20

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 NA NA 6.6 1.96 U 0.680

-0.0121 U 0.0846 U

< 0.0500 0.017 J 0.877 0.894 6.29

-2.76 U NA W-29 01/19/15 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 5.75 16.00 66 4.92 NA NA NA NA NA NA NA 11.0

-7.06 U

-84.1 U 04/13/15 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 6.30 17.90 64 5.36 NA NA NA NA NA NA NA 10.2

-5.70 U 68.9 U 07/13/15 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 6.95 25.20 58 6.09 NA NA NA NA NA NA NA 8.79

-48.2 U

-33.2 U 10/12/15 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 8.85 22.70 51 4.89 U NA NA NA NA NA NA NA 11.5 55.2 U

-132 U 01/14/16 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 8.10 24.50 53 1.56 U NA NA NA NA NA NA NA 6.22 NA 93.4 U 04/19/16 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 7.35 26.90 40 4.41 NA NA NA NA NA NA NA 8.41 NA

-170 U 07/08/16 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 6.95 23.40 37 4.63 U NA NA NA NA NA NA NA 8.46 NA 153 U 10/11/16 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 5.8 22.9 39 3.79 NA NA NA NA NA NA NA 9.79 NA

-47.4 U 01/16/17 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 6.10 20.5 36 11.2 NA NA NA NA NA NA NA 4.94 NA

-39.3 U 04/06/17 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 5.25 22.5 32 3.89 NA NA NA NA NA NA NA 0.947 U NA

-56.4 U 07/10/17 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 6.6 21.5 29 9.80 NA NA NA NA NA NA NA 9.68 NA

-266 U 10/12/17

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 8.1 23.8 32 7.19 NA NA NA NA NA NA NA 5.77 NA

-355 U 01/08/18 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 9.7 27.8 20 7.23 NA NA NA NA NA NA NA 9.82 NA 138 U 04/16/18 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 10.6 30.5 15 3.21 U NA NA NA NA NA NA NA 3.01 U NA

-143 U 07/13/18 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 10 27.2 13 3.71 U NA NA NA NA NA NA NA 4.62 NA 175 U 10/23/18

< 1.0

< 1.0

< 1.0

< 1.0 1.5

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 9.69 29 7.3 1.78 U NA NA NA

< 0.0500 0.0385 J 2.24 2.28 3.98 NA

-68.4 U 01/10/19

< 1.0

< 1.0

< 1.0

< 1.0 1.6

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 7.94 22 6.4 5.04 1.38 0.0673 U 0.746

< 0.0500 0.0333 J 2.17 2.21 3.42 U

-6.15 U 153 U 10/07/19

< 1.0 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 4.8 22.4 11 2.25 U 1.20 0 U 0.972

< 0.050 0.026 J 2.03 2.05 7.67 11.6 U 116 U 04/03/20

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 3.77 13.2 17 0.844 U 0.0704 U 0.0220 U 0.129 U

< 0.0500 0.0167 J 1.36 1.38 8.48 8.62

-38.7 U Page 9 of 20

Table C-1 Summary of Historical Groundwater Analytical Results (2015-2020)

Westinghouse Columbia Fuel Fabrication Facility Hopkins, South Carolina AECOM Project No. 60595649 Carbon Disulfide ug/L Chloroform ug/L cis-1,2-Dichloroethene ug/L Ethylbenzene ug/L Tetrachloroethene ug/L Trichloroethene ug/L Vinyl Chloride ug/L 1,1'-Biphenyl ug/L 2-Methylnaphthalene ug/L Acenaphthene ug/L Carbazole ug/L Fluorene ug/L Naphthalene ug/L Phenanthrene ug/L Fluoride mg/L Ammonia NH3(N) mg/L Nitrate NO3 mg/L Gross Alpha pCi/L Isotopic Uranium 233/234 pCi/L Isotopic Uranium 235/236 pCi/L Isotopic Uranium 238 (HASL300) pCi/L Isotopic Uranium 234 ug/L Isotopic Uranium 235 ug/L Isotopic Uranium 238 ug/L Total Uranium ug/L Gross Beta pCi/L Tc-99 pCi/L Tritium pCi/L 70 700 5

5 2

4 10 15

• 30 50

• 900 20,000 Well Date Radionuclides Inorganics MCL/Action Level VOCs SVOCs W-30 01/19/15 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 11.30 1.32 78 22.4 NA NA NA NA NA NA NA 33.9 54.4 U 21.6 U 04/13/15 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 10.80

<1.00 42 23.7 NA NA NA NA NA NA NA 35.6 4.93 U

-258 U 07/13/15 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 9.65 1.29 69 12.2 NA NA NA NA NA NA NA 21.7

-16.9 U

-24.4 U 10/12/15 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 10.70 1.40 130 12.9 NA NA NA NA NA NA NA 21.4 14.8 U

-75.5 U 01/14/16 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 9.15

<1.00 71 27.8 17.3 0.787 5.61 NA NA NA NA 41.3 NA 129 U 04/19/16 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 8.85

<1.00 44 39.7 19.8 1.46 6.80 NA NA NA NA 41.8 NA

-225 U 07/08/16 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 9.65

<1.00 44 33.5 20.4 1.40 8.12 NA NA NA NA 40.1 NA 31.9 U 10/11/16 NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA 30 NA NA NA NA NA NA NA NA NA NA NA 10/21/16 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 9.88

<1.00 34 44.6 22.9 1.82 7.12 NA NA NA NA 36.2 NA

-132 U 10/24/16 NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA 36 NA NA NA NA NA NA NA NA NA NA NA 01/16/17 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 9.45

<1.00 34 58.2 20.2 1.03 6.09 NA NA NA NA 28.3 NA 55.8 U 04/06/17 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 7.70 1.25 81 35.6 18.3 1.17 5.04 NA NA NA NA 32.3 NA

-139 U 07/10/17 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 7.75 1.44 85 59.6 31.7 2.48 7.62 NA NA NA NA 38.5 NA

-70.7 U 10/12/17

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 8.4 1.5 72 46.1 27.4 1.76 6.85 NA NA NA NA 38.7 NA 7.83 U 01/08/18 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 8.7 1.62 49 54.4 28.8 3.09 10.9 NA NA NA NA 52.6 45.4 365 U 04/16/18 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 8.5 2.13 68 60.0 34.4 2.49 10.2 NA NA NA NA 44.8 NA

-89.6 U 07/13/18 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 8.82 1.95 70 35.0 22.2 1.36 7.02 NA NA NA NA 35.5 NA 89.8 U 10/23/18

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 8.94 1.49 47 23.7 15.0 0.509 4.40

< 0.0500 0.298 12.4 12.7 26.5 NA 38.6 U 01/15/19

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 9.06 0.956 45 38.6 29.3 2.83 10.1

< 0.0500 0.533 22.4 22.9 30.8 32.6 U

-199 U 10/07/19

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 8.06 1.83 120 7.57 11.5 0.914 3.31

< 0.050 0.199 8.71 8.91 20.8 49.7 443 U 04/13/20

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 7.98 0.932 120 14.2 8.43 0.236 2.55

< 0.0500 0.173 6.91 7.08 33.9 48.4

-133 U W-32 01/19/15 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 4.55 54.40 150 6.63 NA NA NA NA NA NA NA 240 351 NA 01/29/15 NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA

-35.3 U 04/13/15 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 5.00 48.00 160 3.52 NA NA NA NA NA NA NA 200 277

-25.1 U 07/13/15 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 4.66 75.10 190 8.08 NA NA NA NA NA NA NA 196 390

-46.7 U 10/12/15 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 3.11 14.00 78 8.56 NA NA NA NA NA NA NA 114 251

-2.02 U 01/14/16 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 4.31 51.40 190 6.22 NA NA NA NA NA NA NA 167 291 141 U 04/19/16 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 4.59 44.30 200 3.60 NA NA NA NA NA NA NA 223 327

-13.5 U 07/08/16 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 4.83 57.80 150 1.90 U NA NA NA NA NA NA NA 189 235 U 164 U 10/11/16 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 3.87 49.0 120 1.83 U NA NA NA NA NA NA NA 180 410

-104 U 01/17/17 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 4.52 43.7 150 11.4 NA NA NA NA NA NA NA 191 301 55.8 U 04/07/17 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 5.00 65.6 130 6.76 NA NA NA NA NA NA NA 179 NA 169 U 07/10/17 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 4.61 69.9 170 8.45 NA NA NA NA NA NA NA 201 402

-34.3 U 10/12/17

< 1.0

< 1.0

< 1.0

< 1.0 1.3

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 4.25 62.1 180 8.21 NA NA NA NA NA NA NA 207 300

-303 U 01/08/18 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 4.49 64.7 170 3.04 U NA NA NA NA NA NA NA 187 293 170 U 04/16/18 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 4.59 70 200 6.27 NA NA NA NA NA NA NA 226 377

-136 U 07/13/18 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 4.04 90 210 22.4 0.618 0.0959 U 0.441 NA NA NA NA 199 388 276 U 10/19/18

< 1.0

< 1.0

< 1.0

< 1.0 1.5

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 3.61 62.5 240 5.00 NA NA NA

< 0.0500

< 0.0700 0.223 0.223 127 259

-24.9 U 01/11/19

< 1.0

< 1.0

< 1.0

< 1.0 1.3

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 3.26 54.5 210 8.41 0.360 0.0769 U 0.198 U

< 0.0500

< 0.0700 0.296 0.296 176 307

-28.8 U 06/05/19

< 1.0

< 1.0

< 1.0

< 1.0 1.6

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 3.56 53.5 210 8.88 0.267 U 0 U 0.0119 U

< 0.0500

< 0.0700 0.31 0.31 206 273

-286 U 10/08/19

< 1.0

< 1.0

< 1.0

< 1.0 1.4

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 3.66 47.9 170 7.17 0.322

-0.00982 U 0.191

< 0.050

< 0.070 0.224 0.224 175 321 81.8 U 04/10/20

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 3.5 34.2 140 3.47

-0.0634 U

-0.0231 U

-0.0103 U

< 0.0500

< 0.0700 0.154 J 0.154 J 106 270

-54.0 U Page 10 of 20

Table C-1 Summary of Historical Groundwater Analytical Results (2015-2020)

Westinghouse Columbia Fuel Fabrication Facility Hopkins, South Carolina AECOM Project No. 60595649 Carbon Disulfide ug/L Chloroform ug/L cis-1,2-Dichloroethene ug/L Ethylbenzene ug/L Tetrachloroethene ug/L Trichloroethene ug/L Vinyl Chloride ug/L 1,1'-Biphenyl ug/L 2-Methylnaphthalene ug/L Acenaphthene ug/L Carbazole ug/L Fluorene ug/L Naphthalene ug/L Phenanthrene ug/L Fluoride mg/L Ammonia NH3(N) mg/L Nitrate NO3 mg/L Gross Alpha pCi/L Isotopic Uranium 233/234 pCi/L Isotopic Uranium 235/236 pCi/L Isotopic Uranium 238 (HASL300) pCi/L Isotopic Uranium 234 ug/L Isotopic Uranium 235 ug/L Isotopic Uranium 238 ug/L Total Uranium ug/L Gross Beta pCi/L Tc-99 pCi/L Tritium pCi/L 70 700 5

5 2

4 10 15

• 30 50

• 900 20,000 Well Date Radionuclides Inorganics MCL/Action Level VOCs SVOCs W-33 01/20/15 NA NA NA NA NA NA NA NA NA NA NA NA NA NA

<0.50

<1.00 7.9 1.86 U NA NA NA NA NA NA NA 2.83 U 95.3 U 109 U 04/14/15 NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA

-0.314 U NA NA NA NA NA NA NA 2.00 U 53.6 U

-186 U 04/16/15 NA NA NA NA NA NA NA NA NA NA NA NA NA NA

<0.50

<1.00 6.9 NA NA NA NA NA NA NA NA NA NA NA 07/10/15 NA NA NA NA NA NA NA NA NA NA NA NA NA NA

<0.50

<1.00 7.5 1.99 U NA NA NA NA NA NA NA 5.26

-9.39 U 38.6 U 10/09/15 NA NA NA NA NA NA NA NA NA NA NA NA NA NA

<0.50

<1.00 6.7 1.15 U NA NA NA NA NA NA NA 11.2 102 U

-91.0 U 01/18/16 NA NA NA NA NA NA NA NA NA NA NA NA NA NA

<0.50

<1.00 7.3 1.01 U NA NA NA NA NA NA NA 16.1 NA 270 U 04/18/16 NA NA NA NA NA NA NA NA NA NA NA NA NA NA

<0.50

<1.00 9

2.51 U NA NA NA NA NA NA NA 8.36 NA

-172 U 07/05/16 NA NA NA NA NA NA NA NA NA NA NA NA NA NA

<0.50

<1.00 12 2.00 U NA NA NA NA NA NA NA 5.01 NA 362 U 10/13/16 NA NA NA NA NA NA NA NA NA NA NA NA NA NA

<0.50

<1.00 16 10.2 NA NA NA NA NA NA NA 20.8 NA

-189 U 01/11/17 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 0.00

<1.00 9.9 28.8 0.524 0.175 U 0.965 NA NA NA NA 22.1 NA 189 U 04/03/17 NA NA NA NA NA NA NA NA NA NA NA NA NA NA

<0.50

<1.00 10 10.6 NA NA NA NA NA NA NA 36.3 NA

-98.4 U 07/11/17 NA NA NA NA NA NA NA NA NA NA NA NA NA NA

<0.50

<1.00 12 15.0 0.891 0.205 U 0.749 NA NA NA NA 15.3 NA 143 U 10/12/17

< 5.0

< 5.0

< 5.0

< 5.0 560 77

< 5.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80

<0.50

<1.00 11 9.80 NA NA NA NA NA NA NA 11.4 NA

-191 U 01/12/18 NA NA NA NA NA NA NA NA NA NA NA NA NA NA

<0.50

<1.00 10 9.88 NA NA NA NA NA NA NA 13.5 NA 198 U 04/17/18 NA NA NA NA NA NA NA NA NA NA NA NA NA NA

<0.50

<1.00 9.7 6.11 NA NA NA NA NA NA NA 11.1 NA 23.1 U 07/10/18 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 0.166

<1.00 11 6.90 NA NA NA NA NA NA NA 13.6 NA 77.0 U 10/16/18

< 1.0

< 1.0 2

< 1.0 190 17

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.187 0.0112 10

-0.0946 U NA NA NA

< 0.0500

< 0.0700

< 0.200

< 0.200 5.22 NA 211 U 01/22/19

< 1.0

< 1.0

< 1.0

< 1.0 140 18

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.193 0.054 10 0.847 U 0.190 U

-0.0251 U 0.106 U

< 0.0500

< 0.0700

< 0.200

< 0.200 2.55 U 3.72 U

-174 U 10/17/19

< 1.0

< 1.0 1.0

< 1.0 300 38

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.152 0.0134 13 2.89 U 0.102 U 0.0445 U 0.0274 U

< 0.050

< 0.070

< 0.200

< 0.200 7.78

-24.7 U

-44.2 U 04/16/20

< 5.0

< 5.0

< 5.0

< 5.0 270 33

< 5.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.146 0.0194 8.2 2.26 U

-0.0495 U 0.0619 U 0.206 U

< 0.0500

< 0.0700

< 0.200

< 0.200 5.00 2.90 U 65.3 U W-35 11/01/18

< 5.0

< 5.0

< 5.0

< 5.0

< 5.0

< 5.0

< 2.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.026 0.0147 5.5 0.190 U 0.299 U 0.0951 U 0.115 U

< 0.0500

< 0.0700

< 0.200

< 0.200 3.28 U

-1.89 U NA 01/22/19

< 1.0

< 1.0

< 1.0

< 1.0 2.1

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.007 0.0449 4.2 0.901 U 0.175 U 0.0897 U 0.489

< 0.0500

< 0.0700

< 0.200

< 0.200 1.33 U

-24.6 U NA 10/02/19

< 1.0

< 1.0

< 1.0

< 1.0 2.6

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.025 0.0075 3.2 0.793 U 0.304 0.0450 U 0.109

< 0.050

< 0.070

< 0.200

< 0.200 3.54 U 21.7 U NA 04/21/20

< 1.0

< 1.0

< 1.0

< 1.0 2.5

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.022 0.0186 3.3 0.263 U 0.123 U 0.0570 U 0.00288 U

< 0.0500

< 0.0700

< 0.200

< 0.200 2.32 U

-0.918 U NA W-36 08/30/18

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0 NA NA NA NA NA NA NA NA NA 0.17 6.82 NA NA NA NA NA NA NA 1.90 U NA 253 U 11/01/18

< 5.0

< 5.0

< 5.0

< 5.0

< 5.0

< 5.0

< 2.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.005 0.0527 0.27

-0.260 U 0.00300 U 0.0424 U 0.0144 U

< 0.0500

< 0.0700

< 0.200

< 0.200 0.503 U

-17.6 U NA 01/18/19

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.005 0.0408 0.055 1.97 U 0.433 0.240 0.204 U

< 0.0500

< 0.0700

< 0.200

< 0.200 3.03 U

-15.4 U NA 10/02/19

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.007 0.0089 0.11 0.270 U 0.148 U

-0.0134 U

-0.0108 U

< 0.050

< 0.070

< 0.200

< 0.200

-0.343 U 15.0 U NA 04/20/20

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.014 0.025 0.056 0.779 U

-0.0208 U 0 U

-0.0293 U

< 0.0500

< 0.0700

< 0.200

< 0.200 4.21

-1.03 U NA W-37 08/05/18 NA NA NA NA NA NA NA NA NA NA NA NA NA NA

<0.50

<1.00 2.6 4.75 NA NA NA NA NA NA NA 5.08 NA 203 U 10/18/18

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.03 0.0268 2.8 0.00882 U NA NA NA

< 0.0500

< 0.0700

< 0.200

< 0.200 1.89 U NA NA 01/14/19

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.01 0.0218 3.6 0.230 U 0.0532 U 0.0713 U 0.238

< 0.0500

< 0.0700

< 0.200

< 0.200 0.997 U

-21.3 U NA 10/02/19

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.02 0.0088 3.5 1.75 U 0.103 U

-0.0108 U 0.0277 U

< 0.050

< 0.070 0.0936 J 0.0936 J

-0.310 U

-14.9 U NA 04/08/20

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.029 0.01 2

0.361 U

-0.00250 U

-0.0274 U

-0.0770 U

< 0.0500

< 0.0700

< 0.200

< 0.200 0.819 U 1.37 U NA Page 11 of 20

Table C-1 Summary of Historical Groundwater Analytical Results (2015-2020)

Westinghouse Columbia Fuel Fabrication Facility Hopkins, South Carolina AECOM Project No. 60595649 Carbon Disulfide ug/L Chloroform ug/L cis-1,2-Dichloroethene ug/L Ethylbenzene ug/L Tetrachloroethene ug/L Trichloroethene ug/L Vinyl Chloride ug/L 1,1'-Biphenyl ug/L 2-Methylnaphthalene ug/L Acenaphthene ug/L Carbazole ug/L Fluorene ug/L Naphthalene ug/L Phenanthrene ug/L Fluoride mg/L Ammonia NH3(N) mg/L Nitrate NO3 mg/L Gross Alpha pCi/L Isotopic Uranium 233/234 pCi/L Isotopic Uranium 235/236 pCi/L Isotopic Uranium 238 (HASL300) pCi/L Isotopic Uranium 234 ug/L Isotopic Uranium 235 ug/L Isotopic Uranium 238 ug/L Total Uranium ug/L Gross Beta pCi/L Tc-99 pCi/L Tritium pCi/L 70 700 5

5 2

4 10 15

• 30 50

• 900 20,000 Well Date Radionuclides Inorganics MCL/Action Level VOCs SVOCs W-38 01/19/15 NA NA NA NA NA NA NA NA NA NA NA NA NA NA

<0.50

<1.00 11 0.504 U NA NA NA NA NA NA NA 4.52 U 89.8 U 157 U 04/13/15 NA NA NA NA NA NA NA NA NA NA NA NA NA NA

<0.50

<1.00 11 1.62 U NA NA NA NA NA NA NA 6.86 34.4 U 66.9 U 07/13/15 NA NA NA NA NA NA NA NA NA NA NA NA NA NA

<0.50

<1.00 9.9 1.37 U NA NA NA NA NA NA NA 2.37 U

-38.9 U 140 U 10/12/15 NA NA NA NA NA NA NA NA NA NA NA NA NA NA

<0.50

<1.00 9.1 1.87 U NA NA NA NA NA NA NA 3.32 U

-32.6 U

-131 U 01/14/16 NA NA NA NA NA NA NA NA NA NA NA NA NA NA

<0.50

<1.00 9.1 0.459 U NA NA NA NA NA NA NA 6.05 NA 54.9 U 04/19/16 NA NA NA NA NA NA NA NA NA NA NA NA NA NA

<0.50

<1.00 8.1 2.32 NA NA NA NA NA NA NA 3.18 NA 159 U 07/08/16 NA NA NA NA NA NA NA NA NA NA NA NA NA NA

<0.50

<1.00 8.8 NA NA NA NA NA NA NA NA NA NA NA 10/11/16 NA NA NA NA NA NA NA NA NA NA NA NA NA NA

<0.50

<1.00 9.2 NA NA NA NA NA NA NA NA NA NA NA 01/17/17 NA NA NA NA NA NA NA NA NA NA NA NA NA NA

<0.50

<1.00 8.3 NA NA NA NA NA NA NA NA NA NA NA 04/07/17 NA NA NA NA NA NA NA NA NA NA NA NA NA NA

<0.50

<1.00 14 NA NA NA NA NA NA NA NA NA NA NA 07/10/17 NA NA NA NA NA NA NA NA NA NA NA NA NA NA

<0.50

<1.00 7.1 NA NA NA NA NA NA NA NA NA NA NA 10/03/17 NA NA NA NA NA NA NA NA NA NA NA NA NA NA

<0.50

<1.00 6.3 NA NA NA NA NA NA NA NA NA NA NA 01/09/18 NA NA NA NA NA NA NA NA NA NA NA NA NA NA

<0.50

<1.00 6.5 NA NA NA NA NA NA NA NA NA NA NA 04/20/18 NA NA NA NA NA NA NA NA NA NA NA NA NA NA

<0.50

<1.00 7.2 NA NA NA NA NA NA NA NA NA NA NA 07/13/18 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 0.148

<1.00 6.3 NA NA NA NA NA NA NA NA NA NA NA 08/05/18 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 0.161 0.112 6.6 2.03 U NA NA NA NA NA NA NA 4.81 NA 219 U 08/31/18 NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA

< 0.02 NA NA NA NA NA NA NA NA NA NA NA 10/18/18

< 1.0

< 1.0

< 1.0

< 1.0 3.6 11

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.127 0.0268 5.6 0.0942 U NA NA NA

< 0.0500

< 0.0700 0.196 J 0.196 J 1.46 U NA NA 10/23/18

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 NA NA 7.8 NA NA NA NA NA NA NA NA NA NA NA 01/09/19

< 1.0

< 1.0

< 1.0

< 1.0 3.2 9.5

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.104 0.0321 5

0.366 U 0.606 0.210 0.309

< 0.0500

< 0.0700 0.197 J 0.197 J 0.689 U

-15.1 U NA 10/04/19

< 1.0

< 1.0

< 1.0

< 1.0 1.8 11

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.176 0.0141 4.3 2.54 U 0.106 U 0 U 0.128

< 0.050

< 0.070 0.183 J 0.183 J 2.43 U

-1.12 U NA 04/03/20

< 1.0

< 1.0

< 1.0

< 1.0 1.4 5.7

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.191 0.0275 3.1 0.335 U 0.105 U 0.0394 U 0.0638 U

< 0.0500

< 0.0700 0.092 J 0.092 J 0.977 U

-0.322 U NA W-39 01/20/15 NA NA NA NA NA NA NA NA NA NA NA NA NA NA

<0.50

<1.00 120 3.67 NA NA NA NA NA NA NA 28.1 45.5 U 20.2 U 04/14/15 NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA 4.34 U NA NA NA NA NA NA NA 22.6 90.1 U 99.8 U 04/17/15 NA NA NA NA NA NA NA NA NA NA NA NA NA NA

<0.50

<1.00 94 NA NA NA NA NA NA NA NA NA NA NA 07/15/15 NA NA NA NA NA NA NA NA NA NA NA NA NA NA

<0.50

<1.00 6.8 3.23 U NA NA NA NA NA NA NA 13.3

-35.0 U

-144 U 10/13/15 NA NA NA NA NA NA NA NA NA NA NA NA NA NA

<0.50

<1.00 95 3.63 U NA NA NA NA NA NA NA 15.2 124 U

-58.4 U 01/21/16 NA NA NA NA NA NA NA NA NA NA NA NA NA NA

<0.50

<1.00 130 0.635 U NA NA NA NA NA NA NA 19.5 NA 315 U 04/21/16 NA NA NA NA NA NA NA NA NA NA NA NA NA NA

<0.50

<1.00 93 2.63 U NA NA NA NA NA NA NA 35.8

-21.4 U

-12.9 U 07/12/16 NA NA NA NA NA NA NA NA NA NA NA NA NA NA

<0.50

<1.00 84 4.91 NA NA NA NA NA NA NA 13.3 NA 323 U 10/13/16 NA NA NA NA NA NA NA NA NA NA NA NA NA NA

<0.50

<1.00 97 8.05 NA NA NA NA NA NA NA 22.9 NA

-148 U 01/13/17 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 0.00

<1.00 89 14.1 NA NA NA NA NA NA NA 18.4 NA 165 U 04/07/17 NA NA NA NA NA NA NA NA NA NA NA NA NA NA

<0.50

<1.00 110 20.2 0.445 0.334 U 0.159 U NA NA NA NA 15.7 NA

-139 U 07/11/17 NA NA NA NA NA NA NA NA NA NA NA NA NA NA

<0.50

<1.00 190 14.0 2.09 0.263 U 0.338 NA NA NA NA 15.5 NA

-39.7 U 10/13/17

< 5.0

< 5.0

< 5.0

< 5.0 360

< 5.0

< 5.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80

<0.50

<1.00 130 7.81 NA NA NA NA NA NA NA 18.1 NA

-265 U 01/15/18 NA NA NA NA NA NA NA NA NA NA NA NA NA NA

<0.50

<1.00 100 16.7 0.558 U 0.715 0.311 U NA NA NA NA 13.2 NA 99.2 U 04/20/18 NA NA NA NA NA NA NA NA NA NA NA NA NA NA

<0.50

<1.00 110 11.1 NA NA NA NA NA NA NA 15.5 NA

-48.5 U 07/12/18 NA NA NA NA NA NA NA NA NA NA NA NA NA NA

<0.50

<1.00 85 12.2 NA NA NA NA NA NA NA 13.1 NA 174 U 10/25/18

< 5.0

< 5.0 5

< 5.0 300

< 5.0

< 5.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.099 0.0318 120 3.36 U NA NA NA

< 0.0500

< 0.0700

< 0.200

< 0.200 12.1 NA 433 U 01/21/19

< 1.0

< 1.0 3.8

< 1.0 190 3.5

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.009 0.067 96 3.66 U 0.367 0.340 0.179 U

< 0.0500

< 0.0700

< 0.200

< 0.200 12.6 4.35 U 488 U 10/18/19

< 5.0

< 5.0 13

< 5.0 290 5.2

< 5.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.024 0.0218 73 1.22 U

-0.0592 U 0.00196 U 0.149 U

< 0.050

< 0.070

< 0.200

< 0.200 8.84 0.726 U 174 U 04/24/20

< 1.0

< 1.0 18

< 1.0 390 7.6

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.021 0.0182 72 6.68

-0.0345 U 0.0199 U

-0.000162 U < 0.0500

< 0.0700

< 0.200

< 0.200 5.51 7.39 23.7 U Page 12 of 20

Table C-1 Summary of Historical Groundwater Analytical Results (2015-2020)

Westinghouse Columbia Fuel Fabrication Facility Hopkins, South Carolina AECOM Project No. 60595649 Carbon Disulfide ug/L Chloroform ug/L cis-1,2-Dichloroethene ug/L Ethylbenzene ug/L Tetrachloroethene ug/L Trichloroethene ug/L Vinyl Chloride ug/L 1,1'-Biphenyl ug/L 2-Methylnaphthalene ug/L Acenaphthene ug/L Carbazole ug/L Fluorene ug/L Naphthalene ug/L Phenanthrene ug/L Fluoride mg/L Ammonia NH3(N) mg/L Nitrate NO3 mg/L Gross Alpha pCi/L Isotopic Uranium 233/234 pCi/L Isotopic Uranium 235/236 pCi/L Isotopic Uranium 238 (HASL300) pCi/L Isotopic Uranium 234 ug/L Isotopic Uranium 235 ug/L Isotopic Uranium 238 ug/L Total Uranium ug/L Gross Beta pCi/L Tc-99 pCi/L Tritium pCi/L 70 700 5

5 2

4 10 15

• 30 50

• 900 20,000 Well Date Radionuclides Inorganics MCL/Action Level VOCs SVOCs W-40 11/29/18

< 5.0

< 5.0

< 5.0

< 5.0

< 5.0

< 5.0

< 2.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.124 0.0203 4.6 6.93 0.0255 U 0.0314 U 0.0588 U

< 0.0500

< 0.0700

< 0.200

< 0.200 5.20 11.9 U NA 01/24/19

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.164 0.0552 2.6 3.21 0.519 0.301 U 0.409

< 0.0500

< 0.0700 0.142 J 0.142 J 3.45 U

-29.3 U NA 10/15/19

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.166 0.0203 4.3 0.796 U 0.0131 U 0.0454 U 0.129 U

< 0.050

< 0.070

< 0.200

< 0.200 3.44 U

-9.52 U NA 04/16/20

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.139 0.0158 2.4 1.22 U 0.154 U 0.0534 U 0.104 U

< 0.0500

< 0.0700

< 0.200

< 0.200 4.19

-1.41 U NA W-41R 01/12/15

< 1.0

< 1.0 1.2

< 1.0 190 37

< 2.0

< 5.1

< 5.1

< 5.1

< 5.1

< 5.1

< 5.1

< 5.1

<0.50

<1.00 56 4.02 U NA NA NA NA NA NA NA 22.0 33.9 U

-91.2 U 04/09/15

< 1.0

< 1.0

< 1.0

< 1.0 130 21

< 1.0

< 5.0

< 5.0

< 5.0

< 5.0

< 5.0

< 5.0

< 5.0

<0.50

<1.00 51

-0.0761 U NA NA NA NA NA NA NA 17.6 62.2 U

-18.6 U 07/10/15

< 1.0

< 1.0

< 1.0

< 1.0 140 21

< 1.0

< 5.0

< 5.0

< 5.0

< 5.0

< 5.0

< 5.0

< 5.0

<0.50

<1.00 54 6.77 NA NA NA NA NA NA NA 22.2 13.7 U

-119 U 10/09/15

< 1.0

< 1.0

< 1.0

< 1.0 88 9.6

< 1.0

< 5.0

< 5.0

< 5.0

< 5.0

< 5.0

< 5.0

< 5.0

<0.50

<1.00 34 1.70 U NA NA NA NA NA NA NA 13.0 86.5 U

-175 U 01/20/16

< 1.0

< 1.0

< 1.0

< 1.0 53 4

< 1.0

< 5.0

< 5.0

< 5.0

< 5.0

< 5.0

< 5.0

< 5.0

<0.50

<1.00 61

-0.192 U NA NA NA NA NA NA NA 19.7 NA 308 U 04/18/16

< 1.0

< 1.0

< 1.0

< 1.0 84 6.8

< 1.0

< 5.0

< 5.0

< 5.0

< 5.0

< 5.0

< 5.0

< 5.0

<0.50

<1.00 80 4.02 U NA NA NA NA NA NA NA 25.7 NA

-370 U 07/05/16

< 1.0

< 1.0

< 1.0

< 1.0 150 14

< 2.0

< 6.0

< 6.0

< 6.0

< 6.0

< 6.0

< 6.0

< 6.0

<0.50

<1.00 66 4.01 U NA NA NA NA NA NA NA 24.6 NA 179 U 10/06/16

< 1.0

< 1.0

< 1.0

< 1.0 150 18

< 2.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80

<0.50

<1.00 75 16.4 0.450 0.0853 U 0.105 U NA NA NA NA 27.1 NA

-267 U 01/10/17

< 1.0

< 1.0

< 1.0

< 1.0 180 21

< 2.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.00

<1.00 64 12.6 NA NA NA NA NA NA NA 24.1 NA

-26.6 U 04/03/17

< 1.0

< 1.0

< 1.0

< 1.0 190 16

< 2.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80

<0.50

<1.00 62 7.57 NA NA NA NA NA NA NA 25.7 NA 55.5 U 07/06/17

< 1.0

< 1.0

< 1.0

< 1.0 160 8.8

< 2.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80

<0.50

<1.00 63 6.07 NA NA NA NA NA NA NA 20.0 NA 122 U 10/12/17 NA NA NA NA NA NA NA NA NA NA NA NA NA NA

<0.50

<1.00 NA 12.6 NA NA NA NA NA NA NA 23.5 NA

-228 U 01/09/18

< 5.0

< 5.0

< 5.0

< 5.0 220 19

< 5.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80

<0.50

<1.00 65 9.26 NA NA NA NA NA NA NA 19.7 NA 85.3 U 04/10/18

< 5.0

< 5.0

< 5.0

< 5.0 260 24

< 5.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80

<0.50

<1.00 76 2.42 U NA NA NA NA NA NA NA 16.4 NA 2.61 U 07/10/18

< 5.0

< 5.0

< 5.0

< 5.0 300 24

< 5.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80

<0.50

<1.00 67 12.4 NA NA NA NA NA NA NA 14.2 NA 473 U 10/17/18

< 5.0

< 5.0

< 5.0

< 5.0 310 23

< 5.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.041 0.033 55

-0.201 U NA NA NA

< 0.0500

< 0.0700

< 0.200

< 0.200 12.1 NA

-0.957 U 01/23/19

< 1.0

< 1.0 5

< 1.0 200 6.9

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.056 0.0777 44 2.13 U 0.281 0.226 U 0.149 U

< 0.0500

< 0.0700

< 0.200

< 0.200 8.44

-11.4 U

-92.5 U 10/14/19

< 1.0

< 1.0 4.4

< 1.0 190 14

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.03 0.0299 65 8.93 0.0652 U 0.0336 U 0.0757 U

< 0.050

< 0.070

< 0.200

< 0.200 14.3

-3.57 U 223 U 04/17/20

< 1.0

< 1.0 3.8

< 1.0 180 4

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.007 0.0181 48

-0.359 U 0.119 U

-0.0106 U

-0.0257 U

< 0.0500

< 0.0700

< 0.200

< 0.200 2.44 U 12.1 49.0 U W-42 08/30/18

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0 NA NA NA NA NA NA NA NA NA 6.6 43.4 1.68 0.296 U 1.78 NA NA NA NA 49.2 NA 162 U 11/04/18

< 5.0

< 5.0

< 5.0

< 5.0

< 5.0

< 5.0

< 2.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 1.49 0.429 4

1.01 U 0.300 U 0.0996 U 0.209 U

< 0.0500

< 0.0700

< 0.200

< 0.200 1.96 U

-13.3 U NA 01/25/19

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 1.51 0.153 3.6 1.90 U 0.376 0.420 0.280

< 0.0500

< 0.0700

< 0.200

< 0.200 8.61 18.4 U NA 10/22/19

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 1.99 0.806 4.7 0.753 U

-0.00113 U 0.110 U 0.0468 U

< 0.050

< 0.070

< 0.200

< 0.200 3.16 U 5.77 U NA 04/23/20

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 1.6 0.197 2.9 0.456 U

-0.0703 U

-0.0113 U

-0.000541 U < 0.0500

< 0.0700

< 0.200

< 0.200 3.17 2.64 U NA Page 13 of 20

Table C-1 Summary of Historical Groundwater Analytical Results (2015-2020)

Westinghouse Columbia Fuel Fabrication Facility Hopkins, South Carolina AECOM Project No. 60595649 Carbon Disulfide ug/L Chloroform ug/L cis-1,2-Dichloroethene ug/L Ethylbenzene ug/L Tetrachloroethene ug/L Trichloroethene ug/L Vinyl Chloride ug/L 1,1'-Biphenyl ug/L 2-Methylnaphthalene ug/L Acenaphthene ug/L Carbazole ug/L Fluorene ug/L Naphthalene ug/L Phenanthrene ug/L Fluoride mg/L Ammonia NH3(N) mg/L Nitrate NO3 mg/L Gross Alpha pCi/L Isotopic Uranium 233/234 pCi/L Isotopic Uranium 235/236 pCi/L Isotopic Uranium 238 (HASL300) pCi/L Isotopic Uranium 234 ug/L Isotopic Uranium 235 ug/L Isotopic Uranium 238 ug/L Total Uranium ug/L Gross Beta pCi/L Tc-99 pCi/L Tritium pCi/L 70 700 5

5 2

4 10 15

• 30 50

• 900 20,000 Well Date Radionuclides Inorganics MCL/Action Level VOCs SVOCs W-43 01/20/15 NA NA NA NA NA NA NA NA NA NA NA NA NA NA

<0.50

<1.00 6.4

-1.18 U NA NA NA NA NA NA NA 4.36 71.9 U

-15.2 U 04/14/15 NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA

-1.05 U NA NA NA NA NA NA NA 3.67 100 U

-152 U 04/17/15 NA NA NA NA NA NA NA NA NA NA NA NA NA NA

<0.50

<1.00 7

NA NA NA NA NA NA NA NA NA NA NA 07/15/15 NA NA NA NA NA NA NA NA NA NA NA NA NA NA

<0.50

<1.00 74 0.462 U NA NA NA NA NA NA NA 7.50

-46.1 U

-96.3 U 10/13/15 NA NA NA NA NA NA NA NA NA NA NA NA NA NA

<0.50

<1.00 6.7

-0.514 U NA NA NA NA NA NA NA 4.78 25.1 U

-290 U 01/21/16 NA NA NA NA NA NA NA NA NA NA NA NA NA NA

<0.50

<1.00 6

0.0304 U NA NA NA NA NA NA NA 6.41 NA 371 U 04/21/16 NA NA NA NA NA NA NA NA NA NA NA NA NA NA

<0.50

<1.00 5.5 2.53 U NA NA NA NA NA NA NA 2.37 U NA

-43.4 U 07/12/16 NA NA NA NA NA NA NA NA NA NA NA NA NA NA

<0.50

<1.00 5.4 0.949 U NA NA NA NA NA NA NA 2.65 U NA

-112 U 10/13/16 NA NA NA NA NA NA NA NA NA NA NA NA NA NA

<0.50

<1.00 5.3 6.93 NA NA NA NA NA NA NA 11.1 NA

-191 U 01/13/17 NA NA NA NA NA NA NA NA NA NA NA NA NA NA

<0.50

<1.00 5.7 12.5 NA NA NA NA NA NA NA 9.60 NA

-25.8 U 04/07/17 NA NA NA NA NA NA NA NA NA NA NA NA NA NA

<0.50

<1.00 5.3 19.5 0.553 0.138 U 0.885 NA NA NA NA 13.5 NA

-97.9 U 07/11/17 NA NA NA NA NA NA NA NA NA NA NA NA NA NA

<0.50

<1.00 5.7 11.6 NA NA NA NA NA NA NA 5.70 NA

-87.9 U 10/13/17

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80

<0.50

<1.00 4.3 6.58 NA NA NA NA NA NA NA 12.1 NA

-68.8 U 01/15/18 NA NA NA NA NA NA NA NA NA NA NA NA NA NA

<0.50

<1.00 4.8 14.2 NA NA NA NA NA NA NA 12.4 NA

-110 U 04/20/18 NA NA NA NA NA NA NA NA NA NA NA NA NA NA

<0.50

<1.00 4.3 7.06 NA NA NA NA NA NA NA 7.17 NA 2.87 U 07/12/18 NA NA NA NA NA NA NA NA NA NA NA NA NA NA

<0.50

<1.00 4.2 8.23 NA NA NA NA NA NA NA 11.3 NA 298 U 10/29/18

< 5.0

< 5.0

< 5.0

< 5.0

< 5.0

< 5.0

< 2.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.034 0.0204 6.6

-0.969 U NA NA NA

< 0.0500

< 0.0700

< 0.200

< 0.200 4.62 U NA

-62.7 U 11/28/18

< 5.0

< 5.0

< 5.0

< 5.0

< 5.0

< 5.0

< 2.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.022 0.0196 7.1

-1.46 U 0.170 U

-0.0377 U 0.171 U

< 0.0500

< 0.0700

< 0.200

< 0.200 4.00 U 27.9 U 36.9 U 01/21/19

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.008 0.0316 9

0.252 U 0.727 0.443 0.246

< 0.0500

< 0.0700

< 0.200

< 0.200 3.36

-6.72 U

-251 U 10/18/19

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.111 0.0198 6.3 0.159 U

-0.0235 U 0.0698 U 0.0475 U

< 0.050

< 0.070

< 0.200

< 0.200 3.16 U

-15.7 U 4.14 U 04/23/20

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.018 0.0353 7.1 1.41 U

-0.0261 U

-0.000217 U 0.0525 U

< 0.0500

< 0.0700

< 0.200

< 0.200 2.36 U 1.60 U

-181 U W-44 01/20/15 NA NA NA NA NA NA NA NA NA NA NA NA NA NA

<0.50

<1.00 4.5 0.659 U NA NA NA NA NA NA NA 2.47 U 88.3 U

-13.0 U 04/14/15 NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA 4.44 NA NA NA NA NA NA NA 4.15 U 12.4 U 29.9 U 04/16/15 NA NA NA NA NA NA NA NA NA NA NA NA NA NA

<0.50

<1.00 3.7 NA NA NA NA NA NA NA NA NA NA NA 07/10/15 NA NA NA NA NA NA NA NA NA NA NA NA NA NA

<0.50

<1.00 2.5 1.40 U NA NA NA NA NA NA NA

-1.71 U

-97.2 U

-230 U 10/09/15 NA NA NA NA NA NA NA NA NA NA NA NA NA NA

<0.50

<1.00 3.9 4.44 NA NA NA NA NA NA NA 2.63 U 125 U

-91.1 U 01/18/16 NA NA NA NA NA NA NA NA NA NA NA NA NA NA

<0.50

<1.00 2.6 1.10 U NA NA NA NA NA NA NA 1.99 U 36.6 U 153 U 04/18/16 NA NA NA NA NA NA NA NA NA NA NA NA NA NA

<0.50

<1.00 2

3.14 U NA NA NA NA NA NA NA 3.45 U NA

-215 U 07/05/16 NA NA NA NA NA NA NA NA NA NA NA NA NA NA

<0.50

<1.00 1.6 NA NA NA NA NA NA NA NA NA NA NA 07/18/16 NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA 18.2 NA NA NA NA NA NA NA 13.2 NA 153 U 10/13/16 NA NA NA NA NA NA NA NA NA NA NA NA NA NA

<0.50

<1.00 3

10.4 NA NA NA NA NA NA NA 9.65 NA

-177 U 01/11/17 NA NA NA NA NA NA NA NA NA NA NA NA NA NA

<0.50

<1.00 3.3 11.4 NA NA NA NA NA NA NA 4.16 U NA

-189 U 04/05/17 NA NA NA NA NA NA NA NA NA NA NA NA NA NA

<0.50

<1.00 2.9 9.55 NA NA NA NA NA NA NA 14.3 NA

-154 U 07/11/17 NA NA NA NA NA NA NA NA NA NA NA NA NA NA

<0.50

<1.00 2.7 8.36 NA NA NA NA NA NA NA 3.87 U NA 160 U 10/12/17

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80

<0.50

<1.00 2.8 19.4 0.949 0.211 U 0.151 U NA NA NA NA 15.9 NA

-126 U 01/12/18 NA NA NA NA NA NA NA NA NA NA NA NA NA NA

<0.50

<1.00 2.4 9.51 NA NA NA NA NA NA NA 8.88 NA 75.2 U 04/17/18 NA NA NA NA NA NA NA NA NA NA NA NA NA NA

<0.50

<1.00 3.2 8.48 NA NA NA NA NA NA NA 6.78 NA

-24.3 U 07/12/18 NA NA NA NA NA NA NA NA NA NA NA NA NA NA

<0.50

<1.00 3.3 8.15 NA NA NA NA NA NA NA 10.6 NA 98.8 U 08/30/18

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0 NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA 10/17/18

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.019 0.017 3.5 2.49 U NA NA NA

< 0.0500

< 0.0700

< 0.200

< 0.200 1.83 U NA 104 U 01/23/19

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.046 0.091 2.9 0.347 U 0.341 U 0.300 U 0.234 U

< 0.0500

< 0.0700

< 0.200

< 0.200 4.49

-14.1 U

-243 U 10/14/19

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.023 0.0186 2.4 3.47 U 0.0335 U 0.0360 U 0.0107 U

< 0.050

< 0.070

< 0.200

< 0.200 0.283 U

-3.15 U

-61.7 U 04/16/20

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80

< 0.1 0.0134 1.7 0.183 U 0.0364 U 0.0426 U 0.0786 U

< 0.0500

< 0.0700

< 0.200

< 0.200 13.3

-0.752 U 44.8 U Page 14 of 20

Table C-1 Summary of Historical Groundwater Analytical Results (2015-2020)

Westinghouse Columbia Fuel Fabrication Facility Hopkins, South Carolina AECOM Project No. 60595649 Carbon Disulfide ug/L Chloroform ug/L cis-1,2-Dichloroethene ug/L Ethylbenzene ug/L Tetrachloroethene ug/L Trichloroethene ug/L Vinyl Chloride ug/L 1,1'-Biphenyl ug/L 2-Methylnaphthalene ug/L Acenaphthene ug/L Carbazole ug/L Fluorene ug/L Naphthalene ug/L Phenanthrene ug/L Fluoride mg/L Ammonia NH3(N) mg/L Nitrate NO3 mg/L Gross Alpha pCi/L Isotopic Uranium 233/234 pCi/L Isotopic Uranium 235/236 pCi/L Isotopic Uranium 238 (HASL300) pCi/L Isotopic Uranium 234 ug/L Isotopic Uranium 235 ug/L Isotopic Uranium 238 ug/L Total Uranium ug/L Gross Beta pCi/L Tc-99 pCi/L Tritium pCi/L 70 700 5

5 2

4 10 15

• 30 50

• 900 20,000 Well Date Radionuclides Inorganics MCL/Action Level VOCs SVOCs W-45 08/05/18 NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA

< 0.02 18.9 12.8 0.404 3.35 NA NA NA NA 8.02 NA 42.0 U 11/04/18

< 5.0

< 5.0

< 5.0

< 5.0

< 5.0

< 5.0

< 2.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80 0.9

< 0.80 0.861 0.409 0.95 4.47 3.55 0.371 0.907

< 0.0500 0.0586 J 2.53 2.58 2.99 U

-20.6 U NA 01/18/19

< 1.0

< 1.0

< 1.0 6.6

< 1.0

< 1.0

< 1.0 7.2 7.2 1.5 6.6 2.4 18 1.4 0.614 1.39 0.74 5.34 1.35 0.351 0.541

< 0.0500 0.0244 J 1.02 1.05 2.70 U

-14.5 U NA 10/02/19

< 1.0

< 1.0

< 1.0 2.3

< 1.0

< 1.0

< 1.0 4.2 12 1.5

< 4.0 1.7 15 1.1 0.633 2.08 0.093 4.37 0.897

-0.0125 U 0.477

< 0.050 0.0216 J 0.983 1

16.6 4.99 U NA 04/15/20

< 1.0

< 1.0

< 1.0 3.4

< 1.0

< 1.0

< 1.0

< 4.0 6

1

< 4.0 1

13

< 0.80 0.61 1.26 0.11 3.46 U 0.0405 U

-0.0108 U 0.0729 U

< 0.0500

< 0.0700

< 0.200

< 0.200 49.5 71.1 NA W-46 11/04/18

< 5.0

< 5.0

< 5.0

< 5.0

< 5.0

< 5.0

< 2.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.033 0.0144 7.6 0.819 U 0.0278 U 0.00163 U 0.0435 U

< 0.0500

< 0.0700

< 0.200

< 0.200 48.6 49.7 NA 01/22/19

< 1.0

< 1.0

< 1.0

< 1.0 1.7

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.015 0.0569 7.6 0.0455 U 0.363 U 0.270 0.362

< 0.0500

< 0.0700

< 0.200

< 0.200 41.3 38.2 U NA 10/21/19

< 1.0

< 1.0

< 1.0

< 1.0 2.5

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.033 0.0129 7.8 0.656 U 0.317 U

-0.103 U 0.0325 U

< 0.050

< 0.070

< 0.200

< 0.200 40.4 62.8 NA 04/22/20

< 1.0

< 1.0

< 1.0

< 1.0 2.2

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.028 0.2 8.7 1.97 U

-0.0421 U 0.0467 U 0.0605 U

< 0.0500

< 0.0700

< 0.200

< 0.200 34.4 55.6 NA W-47 01/21/15 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 4.92 18.30 34 0.0655 U NA NA NA NA NA NA NA 83.1 153 U 40.5 U 04/16/15 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 5.20 15.00 31 1.70 U NA NA NA NA NA NA NA 71.9 116 U

-85.0 U 07/16/15 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 5.35 18.90 36 1.75 U NA NA NA NA NA NA NA 79.4 28.5 U 135 U 10/13/15 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 5.85 20.10 37 2.46 U NA NA NA NA NA NA NA 62.6 177 U 41.9 U 01/20/16 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 4.96 21.00 40 0.604 U NA NA NA NA NA NA NA 71.2 118 U 281 U 04/21/16 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 4.82 20.70 43 1.93 U NA NA NA NA NA NA NA 51.4

-4.45 U

-182 U 07/12/16 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 4.79 19.70 44 3.29 U NA NA NA NA NA NA NA 39.1 NA 128 U 10/18/16 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 4.74 19.0 41 1.89 U NA NA NA NA NA NA NA 38.1 NA

-193 U 01/13/17 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 4.65 19.8 46 5.49 NA NA NA NA NA NA NA 64.5 81.7 95.8 U 04/07/17 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 4.52 20.9 52 2.64 U NA NA NA NA NA NA NA 66.3 NA 168 U 07/12/17 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 5.05 19.8 55 1.62 U NA NA NA NA NA NA NA 61.5 70.2

-87.4 U 10/13/17

< 1.0

< 1.0

< 1.0

< 1.0 1.8

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 4.60 19.6 49 1.53 U NA NA NA NA NA NA NA 73.5 70.6 3.27 U 01/15/18 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 4.47 18.1 55 2.97 U NA NA NA NA NA NA NA 68.7 84.1 149 U 04/22/18 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 4.66 19 62 4.24 NA NA NA NA NA NA NA 56.3 81.0 163 U 07/15/18 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 4.35 21.5 64 7.10 NA NA NA NA NA NA NA 76.8 80.4 71.8 U 08/30/18

< 1.0

< 1.0

< 1.0

< 1.0 2.1

< 1.0

< 1.0 NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA 10/25/18

< 1.0

< 1.0

< 1.0

< 1.0 3.1

< 1.0

< 1.0

< 40

< 8.0

< 8.0

< 40

< 8.0

< 8.0

< 8.0 4

22.9 84 2.23 U NA NA NA

< 0.0500

< 0.0700 0.0797 J 0.0797 J 105 113 47.7 U 01/24/19

< 1.0

< 1.0

< 1.0

< 1.0 2.4

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 4.23 20 71 5.21 0.382

-0.0438 U 0.283

< 0.0500

< 0.0700

< 0.200

< 0.200 91.2 97.8

-255 U 10/17/19

< 1.0

< 1.0

< 1.0

< 1.0 1.6

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 4.45 16.5 42 1.60 U

-0.0328 U

-0.00816 U

-0.0330 U

< 0.050

< 0.070

< 0.200

< 0.200 61.6 94.2 137 U 04/20/20

< 1.0

< 1.0

< 1.0

< 1.0 1.6

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 3.92 16.8 44 1.26 U

-0.0324 U 0.0453 U 0.0103 U

< 0.0500

< 0.0700 0.102 J 0.102 J 56.7 86.8 273 U Page 15 of 20

Table C-1 Summary of Historical Groundwater Analytical Results (2015-2020)

Westinghouse Columbia Fuel Fabrication Facility Hopkins, South Carolina AECOM Project No. 60595649 Carbon Disulfide ug/L Chloroform ug/L cis-1,2-Dichloroethene ug/L Ethylbenzene ug/L Tetrachloroethene ug/L Trichloroethene ug/L Vinyl Chloride ug/L 1,1'-Biphenyl ug/L 2-Methylnaphthalene ug/L Acenaphthene ug/L Carbazole ug/L Fluorene ug/L Naphthalene ug/L Phenanthrene ug/L Fluoride mg/L Ammonia NH3(N) mg/L Nitrate NO3 mg/L Gross Alpha pCi/L Isotopic Uranium 233/234 pCi/L Isotopic Uranium 235/236 pCi/L Isotopic Uranium 238 (HASL300) pCi/L Isotopic Uranium 234 ug/L Isotopic Uranium 235 ug/L Isotopic Uranium 238 ug/L Total Uranium ug/L Gross Beta pCi/L Tc-99 pCi/L Tritium pCi/L 70 700 5

5 2

4 10 15

• 30 50

• 900 20,000 Well Date Radionuclides Inorganics MCL/Action Level VOCs SVOCs W-48 01/12/15

< 1.0

< 1.0 5.4

< 1.0 140 4

< 2.0

< 5.1

< 5.1

< 5.1

< 5.1

< 5.1

< 5.1

< 5.1

<0.50

<1.00 2.3 1.64 U NA NA NA NA NA NA NA 7.15 62.3 U

-48.7 U 04/09/15

< 1.0

< 1.0 7.4

< 1.0 170 5.5

< 1.0

< 5.0

< 5.0

< 5.0

< 5.0

< 5.0

< 5.0

< 5.0

<0.50

<1.00 3.2 2.44 U NA NA NA NA NA NA NA 11.4

-40.5 U

-20.3 U 07/10/15

< 1.0

< 1.0 6.1

< 1.0 170 7.7

< 1.0

< 5.0

< 5.0

< 5.0

< 5.0

< 5.0

< 5.0

< 5.0

<0.50

<1.00 3.4 1.91 U NA NA NA NA NA NA NA 6.43

-5.77 U 96.5 U 10/09/15

< 1.0

< 1.0 6.4

< 1.0 190 8.2

< 1.0

< 5.0

< 5.0

< 5.0

< 5.0

< 5.0

< 5.0

< 5.0

<0.50

<1.00 3.6 0.312 U NA NA NA NA NA NA NA 7.29 74.1 U

-116 U 01/20/16

< 1.0

< 1.0 4.8

< 1.0 190 6.5

< 1.0

< 5.0

< 5.0

< 5.0

< 5.0

< 5.0

< 5.0

< 5.0

<0.50

<1.00 3.8

-2.25 U NA NA NA NA NA NA NA 8.90 95.0 U 98.8 U 04/18/16

< 1.0

< 1.0 4.2

< 1.0 220 7.3

< 1.0

< 5.0

< 5.0

< 5.0

< 5.0

< 5.0

< 5.0

< 5.0

<0.50

<1.00 4.7 0.463 U NA NA NA NA NA NA NA 9.55 NA

-386 U 07/05/16

< 5.0

< 5.0

< 5.0

< 5.0 220 7

< 10

< 5.3

< 5.3

< 5.3

< 5.3

< 5.3

< 5.3

< 5.3

<0.50

<1.00 4.1

-0.109 U NA NA NA NA NA NA NA 10.9 NA

-203 U 10/06/16

< 1.0

< 1.0 3.4

< 1.0 160 5.7

< 2.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80

<0.50

<1.00 4.4

-1.32 U NA NA NA NA NA NA NA 6.53 NA

-133 U 01/10/17

< 1.0

< 1.0 4.3

< 1.0 100 8.7

< 2.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80

<0.50

<1.00 4.7 1.09 U NA NA NA NA NA NA NA 4.15 U NA 15.1 U 04/03/17

< 1.0

< 1.0 4.1

< 1.0 180 8.2

< 2.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80

<0.50

<1.00 4.5 1.00 U NA NA NA NA NA NA NA 15.6 NA

-154 U 07/06/17

< 1.0

< 1.0 3.7

< 1.0 160 7.7

< 2.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80

<0.50

<1.00 4.7

-0.101 U NA NA NA NA NA NA NA 8.47 NA 142 U 10/13/17

< 1.0

< 1.0 3.3

< 1.0 170 7.9

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80

<0.50

<1.00 4

0.497 U NA NA NA NA NA NA NA 6.79 NA 221 U 01/09/18

< 1.0

< 1.0 3.5

< 1.0 170 8.8

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80

<0.50

<1.00 4.6 2.12 U NA NA NA NA NA NA NA 28.3 NA

-33.9 U 04/10/18

< 1.0

< 1.0 4.3

< 1.0 150 7.4

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80

<0.50

<1.00 5

0.0511 U NA NA NA NA NA NA NA 4.88 NA

-87.1 U 07/10/18

< 1.0

< 1.0 3.2

< 1.0 170 6.4

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.389 0.178 4.6 2.93 U NA NA NA NA NA NA NA 16.1 NA 260 U 10/25/18

< 1.0

< 1.0 2.2

< 1.0 150 4.9

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.529 0.0322 5.3 0.639 U NA NA NA

< 0.0500

< 0.0700 0.0922 J 0.0922 J 14.8 NA

-50.0 U 01/24/19

< 1.0

< 1.0 2.1

< 1.0 180 5.1

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.341 0.0678 5

3.90 0.294 0.425 0.194 U

< 0.0500

< 0.0700

< 0.200

< 0.200 15.7

-8.89 U

-303 U 10/21/19

< 1.0

< 1.0 2.1

< 1.0 200 4.9

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.33 0.0446 5.3 0.460 U 0.0449 U 0.106 U 0.0109 U

< 0.050

< 0.070

< 0.200

< 0.200 9.32 13.1 U 87.4 U 04/21/20

< 1.0

< 1.0

< 1.0

< 1.0 1

1.2

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.36 0.0347 5.1

-1.16 U 0.00192 U

-0.0102 U 0.00138 U

< 0.0500

< 0.0700

< 0.200

< 0.200 7.20 13.8

-23.7 U W-49 12/13/18

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.8

< 0.80 0.011 0.0235

< 0.02 3.26 U 0.314 U 0.0196 U 0.198 U

< 0.0500

< 0.0700 0.104 J 0.104 J 0.727 U 27.2 U NA 01/29/19

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.003 0.0152

< 0.02 3.87 0.354 U 0.171 U 0.199 U

< 0.0500

< 0.0700 0.0731 J 0.0731 J 2.72 U

-33.6 U NA 10/24/19

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.003 0.0151

< 0.020 0.196 U 0.154 U 0.0321 U 0.0380 U

< 0.050

< 0.070 0.0695 J 0.0695 J 4.34 U

-2.03 U NA 04/23/20

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.011 0.0229

< 0.02 5.78

-0.0345 U

-0.000261 U 0.0102 U

< 0.0500

< 0.0700 0.0735 J 0.0735 J 6.76

-0.475 U NA W-50 01/24/19

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.8

< 0.80 0.006 0.0609

< 0.02 1.34 U 0.685 0.265 0.188 U

< 0.0500

< 0.0700 0.0876 J 0.0876 J 1.59 U 4.64 U NA 10/15/19

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.035 0.0185

< 0.020 3.48 U 0.279 U 0.0468 U 0.201 U

< 0.050

< 0.070 0.101 J 0.101 J 0.0720 U

-11.1 U NA 04/16/20

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80

< 0.1 0.0171

< 0.02 1.63 U 0.314 U 0.0999 U 0.133 U

< 0.0500

< 0.0700 0.151 J 0.151 J 3.92

-0.473 U NA W-51 09/25/18

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0 NA NA NA NA NA NA NA NA NA 0.027 NA NA NA NA NA NA NA NA NA NA NA 10/09/18 NA NA NA NA NA NA NA

< 20

< 4.0

< 4.0

< 20

< 4.0

< 4.0

< 4.0 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 10/28/18

< 5.0

< 5.0

< 5.0

< 5.0

< 5.0

< 5.0

< 2.0 13

< 0.80

< 0.80 4.5

< 0.80

< 0.80 1.8 0.304 0.274 0.03 NA NA NA NA NA NA NA NA NA NA NA 01/25/19

< 1.0

< 1.0

< 1.0 2.7

< 1.0

< 1.0

< 1.0 12

< 0.80

< 0.80 4.9 1.3 3.5 1.8 0.258 0.106 0.023 2.27 U 0.230 U 0.0672 U 0.123 U

< 0.0500

< 0.0700

< 0.200

< 0.200 3.49 U 5.46 U NA 10/03/19

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0 7.4

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.215 0.256 0.11 0.544 U 0.0146 U 0.0799 U

-0.0705 U

< 0.050

< 0.070

< 0.200

< 0.200 3.56

-16.3 U NA 04/09/20

< 1.0

< 1.0

< 1.0 5.2

< 1.0

< 1.0

< 1.0 13 8.5 1.1 6.1 3

12 2.9 0.173 0.0106 0.046 0.101 U

-0.0978 U

-0.0224 U

-0.0817 U

< 0.0500

< 0.0700

< 0.200

< 0.200 0.258 U

-1.23 U NA W-52 09/24/18

< 1.0

< 1.0 2.6

< 1.0

< 1.0

< 1.0

< 1.0 NA NA NA NA NA NA NA NA NA 0.67 NA NA NA NA NA NA NA NA NA NA NA 10/09/18 NA NA NA NA NA NA NA

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 10/28/18

< 5.0

< 5.0

< 5.0

< 5.0

< 5.0

< 5.0

< 2.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.957 0.0476 2.3 NA NA NA NA NA NA NA NA NA NA NA 01/26/19

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 1.08 0.0346 2.4 0.246 U 0.368 0.0774 U 0.125 U

< 0.0500

< 0.0700

< 0.200

< 0.200 2.71 U

-12.2 U NA 10/03/19

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 1.39 0.0212 1.3

-0.521 U 0.121 U 0.115 0.00124 U

< 0.050

< 0.070

< 0.200

< 0.200 1.61 U

-20.8 U NA 04/09/20

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.992 0.0272 2

2.41 U 0.0567 U 0.00430 U 0.00348 U

< 0.0500

< 0.0700

< 0.200

< 0.200 2.43 U

-0.253 U NA Page 16 of 20

Table C-1 Summary of Historical Groundwater Analytical Results (2015-2020)

Westinghouse Columbia Fuel Fabrication Facility Hopkins, South Carolina AECOM Project No. 60595649 Carbon Disulfide ug/L Chloroform ug/L cis-1,2-Dichloroethene ug/L Ethylbenzene ug/L Tetrachloroethene ug/L Trichloroethene ug/L Vinyl Chloride ug/L 1,1'-Biphenyl ug/L 2-Methylnaphthalene ug/L Acenaphthene ug/L Carbazole ug/L Fluorene ug/L Naphthalene ug/L Phenanthrene ug/L Fluoride mg/L Ammonia NH3(N) mg/L Nitrate NO3 mg/L Gross Alpha pCi/L Isotopic Uranium 233/234 pCi/L Isotopic Uranium 235/236 pCi/L Isotopic Uranium 238 (HASL300) pCi/L Isotopic Uranium 234 ug/L Isotopic Uranium 235 ug/L Isotopic Uranium 238 ug/L Total Uranium ug/L Gross Beta pCi/L Tc-99 pCi/L Tritium pCi/L 70 700 5

5 2

4 10 15

• 30 50

• 900 20,000 Well Date Radionuclides Inorganics MCL/Action Level VOCs SVOCs W-53 09/24/18

< 1.0

< 1.0 33

< 1.0 2

< 1.0 2.1 NA NA NA NA NA NA NA NA NA 2.1 NA NA NA NA NA NA NA NA NA NA NA 10/09/18 NA NA NA NA NA NA NA

< 4.0 4.4 1.1

< 4.0 1.8

< 0.80 1.9 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 10/28/18

< 5.0

< 5.0 19

< 5.0

< 5.0

< 5.0

< 2.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.262 0.0611 0.67 NA NA NA NA NA NA NA NA NA NA NA 01/26/19

< 1.0

< 1.0 46

< 1.0 4.6

< 1.0 2.1

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.069 0.0412 0.063 0.101 U 0.376 0.175 U 0.112 U

< 0.0500

< 0.0700

< 0.200

< 0.200 0.0470 U 17.5 U NA 10/03/19

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0 4.0

< 0.80

< 0.80 4.4 1.0

< 0.80 5.2 0.081 0.0397 0.57 1.61 U 0.0359 U

-0.0157 U

-0.0614 U

< 0.050

< 0.070

< 0.200

< 0.200 1.72 U

-35.1 U NA 04/09/20

< 1.0

< 1.0 5.4

< 1.0 1.3

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0 1.5

< 0.80 4

0.017 0.108 0.033

-0.727 U

-0.0556 U 0.0382 U

-0.0627 U

< 0.0500

< 0.0700

< 0.200

< 0.200 3.20 U 0.874 U NA W-54 09/24/18

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0 NA NA NA NA NA NA NA NA NA 2.2 NA NA NA NA NA NA NA NA NA NA NA 10/08/18 NA NA NA NA NA NA NA

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 10/28/18

< 5.0

< 5.0

< 5.0

< 5.0

< 5.0

< 5.0

< 2.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.264 0.0198 2.9 NA NA NA NA NA NA NA NA NA NA NA 01/26/19

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.153 0.0083 3

-0.0908 U 0.779 0.286 0.405

< 0.0500

< 0.0700

< 0.200

< 0.200 3.58 U 6.19 U NA 10/04/19

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.258 0.0037 2.8 1.55 U 0.0685 U

-0.0666 U 0.0126 U

< 0.050

< 0.070

< 0.200

< 0.200 1.96 U

-19.6 U NA 04/09/20

< 1.0

< 1.0 1.9

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.093 0.0156 1.7 0.275 U

-0.141 U 0.0287 U

-0.0479 U

< 0.0500

< 0.0700

< 0.200

< 0.200 1.60 U

-0.513 U NA W-55 09/24/18

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0 NA NA NA NA NA NA NA NA NA 5.1 NA NA NA NA NA NA NA NA NA NA NA 10/08/18 NA NA NA NA NA NA NA

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 10/27/18

< 5.0

< 5.0

< 5.0

< 5.0

< 5.0

< 5.0

< 2.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.06 0.0342 3.3 NA NA NA NA NA NA NA NA NA NA NA 01/26/19

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.065 0.0059 3.5 466 283 19.1 69.4 0.0459 J 5.6 172 178 84.0

-1.08 U NA 10/04/19

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.062 0.0108 3.7 438 290 16.3 60.5 0.052 5.79 177 183 77.3

-11.9 U NA 04/08/20

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.047 0.026 2

271 197 9.43 39.4 0.032 J 3.77 112 115 52.9

-1.04 U NA W-56 09/25/18

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0 NA NA NA NA NA NA NA NA NA 6.5 NA NA NA NA NA NA NA NA NA NA NA 10/08/18 NA NA NA NA NA NA NA

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 10/27/18

< 5.0

< 5.0

< 5.0

< 5.0

< 5.0

< 5.0

< 2.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.135 0.0213 6.5 NA NA NA NA NA NA NA NA NA NA NA 01/26/19

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.152 0.0078 4.1 257 176 12.1 43.7 0.0343 J 4.05 128 132 57.1 12.7 U NA 10/04/19

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.257 0.009 4.2 264 192 9.18 37.9 0.034 J 4.19 130 134 54.5

-20.5 U NA 04/07/20

< 1.0

< 1.0 1.2

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.241 0.011 2.8 60.9 47.7 2.29 9.79

< 0.0500 0.98 30 31 10.1

-1.35 U NA W-57 09/25/18

< 1.0 1.2

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0 NA NA NA NA NA NA NA NA NA 6.2 NA NA NA NA NA NA NA NA NA NA NA 10/08/18 NA NA NA NA NA NA NA

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 10/27/18

< 5.0

< 5.0

< 5.0

< 5.0

< 5.0

< 5.0

< 2.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.068 0.0144 6.6 NA NA NA NA NA NA NA NA NA NA NA 01/27/19

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.034 0.0739 5.7 1.89 U 0.570 0.212 U 0.304

< 0.0500

< 0.0700 0.247 0.247 1.46 U

-18.9 U NA 10/03/19

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.057 0.0155 4.6 0.202 U

-0.0917 U 0 U 0.0165 U

< 0.050

< 0.070 0.207 0.207 3.09 U

-16.3 U NA 04/07/20

< 1.0

< 1.0 1.7

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.073 0.0155 3.5 8.21 0.00106 U 0.0293 U

-0.0225 U

< 0.0500

< 0.0700

< 0.200

< 0.200 5.21

-0.855 U NA W-58 09/25/18

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0 NA NA NA NA NA NA NA NA NA 17 NA NA NA NA NA NA NA NA NA NA NA 10/08/18 NA NA NA NA NA NA NA

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 10/27/18

< 5.0

< 5.0

< 5.0

< 5.0

< 5.0

< 5.0

< 2.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.117 14.8 16 NA NA NA NA NA NA NA NA NA NA NA 01/27/19

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.1 17.9 11 7.03 3.04 0.500 1.17

< 0.0500 0.0444 J 1.51 1.55 5.66 18.7 U NA 10/04/19

< 1.0

< 1.0 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.18 18.6 9.7 4.21 2.10 0.104 U 0.331 U

< 0.050 0.049 J 1.67 1.72 2.43 U

-26.1 U NA 04/07/20

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.099 6.28 4.3 2.39 U 1.62

-0.0132 U 0.399

< 0.0500 0.0326 J 1.02 1.05 1.85 U

-0.0365 U NA W-59 09/25/18

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0 NA NA NA NA NA NA NA NA NA 26 NA NA NA NA NA NA NA NA NA NA NA 10/08/18 NA NA NA NA NA NA NA

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 10/27/18

< 5.0

< 5.0

< 5.0

< 5.0

< 5.0

< 5.0

< 2.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 1.08 6.69 21 NA NA NA NA NA NA NA NA NA NA NA 01/27/19

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 1.08 9.29 21 80.7 42.7 3.19 10.1

< 0.0500 0.856 28.4 29.2 16.8 6.21 U NA 10/05/19

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 4.18 12.3 14 44.4 38.0 2.02 8.26

< 0.050 0.659 21.6 22.2 17.4 13.0 U NA 04/07/20

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 2.9 8.82 20 25.3 20.1 0.927 4.58

< 0.0500 0.379 12.4 12.8 9.33 7.86 NA Page 17 of 20

Table C-1 Summary of Historical Groundwater Analytical Results (2015-2020)

Westinghouse Columbia Fuel Fabrication Facility Hopkins, South Carolina AECOM Project No. 60595649 Carbon Disulfide ug/L Chloroform ug/L cis-1,2-Dichloroethene ug/L Ethylbenzene ug/L Tetrachloroethene ug/L Trichloroethene ug/L Vinyl Chloride ug/L 1,1'-Biphenyl ug/L 2-Methylnaphthalene ug/L Acenaphthene ug/L Carbazole ug/L Fluorene ug/L Naphthalene ug/L Phenanthrene ug/L Fluoride mg/L Ammonia NH3(N) mg/L Nitrate NO3 mg/L Gross Alpha pCi/L Isotopic Uranium 233/234 pCi/L Isotopic Uranium 235/236 pCi/L Isotopic Uranium 238 (HASL300) pCi/L Isotopic Uranium 234 ug/L Isotopic Uranium 235 ug/L Isotopic Uranium 238 ug/L Total Uranium ug/L Gross Beta pCi/L Tc-99 pCi/L Tritium pCi/L 70 700 5

5 2

4 10 15

• 30 50

• 900 20,000 Well Date Radionuclides Inorganics MCL/Action Level VOCs SVOCs W-60 10/30/18 9.4

< 5.0

< 5.0

< 5.0

< 5.0

< 5.0

< 2.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.016 0.017 0.11 0.958 U 0.250 U 0 U 0.0591 U

< 0.0500

< 0.0700

< 0.200

< 0.200 0.923 U

-23.4 U NA 01/17/19

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.007 0.0798 0.02 0.432 U 0.409 0.290 0.452

< 0.0500

< 0.0700

< 0.200

< 0.200

-0.201 U

-11.1 U NA 10/17/19

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.034 0.0251 0.035 0.200 U 0.0248 U 0.0418 U 0.00356 U

< 0.050

< 0.070

< 0.200

< 0.200 1.38 U

-7.75 U NA 04/10/20

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.024 0.128

< 0.02 0.543 U

-0.0712 U

-0.00912 U

-0.0148 U

< 0.0500

< 0.0700

< 0.200

< 0.200 3.08 U

-1.89 U NA W-61 10/30/18

< 5.0 5.2

< 5.0

< 5.0

< 5.0

< 5.0

< 2.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.086 0.0206 0.051 3.28 U 0.282 U 0.130 U 0.0335 U

< 0.0500

< 0.0700

< 0.200

< 0.200 3.82

-13.4 U NA 01/17/19

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.075 0.0408 0.48

-0.996 U 0.557 0.359 0.365

< 0.0500

< 0.0700

< 0.200

< 0.200 5.01 2.09 U NA 10/17/19

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.036 0.0274 2.5 1.31 U

-0.0719 U 0.0596 U 0.0254 U

< 0.050

< 0.070

< 0.200

< 0.200 0.862 U

-16.1 U NA 04/10/20

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.041 0.055 1.4 0.373 U 0.0228 U

-0.0101 U 0.00788 U

< 0.0500

< 0.0700

< 0.200

< 0.200 6.86

-0.660 U NA W-62 11/01/18

< 1.0

< 1.0

< 1.0

< 1.0 48 1.9

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.02 0.0177 3.6 2.51 U 0.138 U 0.288 U 0.00169 U

< 0.0500

< 0.0700 0.0843 J 0.0843 J 2.26 U

-15.2 U NA 01/18/19

< 1.0

< 1.0

< 1.0

< 1.0 51 1.9

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.01 0.0375 3.9 2.98 U 0.237 U 0.283 U 0.205 U

< 0.0500

< 0.0700 0.0831 J 0.0831 J 3.27 U

-6.16 U NA 10/22/19

< 1.0

< 1.0

< 1.0

< 1.0 42

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.019 0.0162 4.0

-0.106 U 0.0178 U 0.0998 U 0.142 U

< 0.050

< 0.070

< 0.200

< 0.200 4.85

-17.3 U NA 04/17/20

< 1.0

< 1.0

< 1.0

< 1.0 45 1

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.001 0.0127 4.3 1.40 U 0.0392 U

-0.0123 U

-0.0199 U

< 0.0500

< 0.0700

< 0.200

< 0.200

-2.46 U 0.361 U NA W-63 10/31/18

< 5.0

< 5.0

< 5.0

< 5.0

< 5.0

< 5.0

< 2.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.474 0.0647 0.86 1.97 U 0.755 0.0837 U 0.669

< 0.0500

< 0.0700 1.02 1.02 5.84 16.3 U NA 01/17/19

< 1.0

< 1.0

< 1.0

< 1.0 1.4

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.502 0.0632 0.16 3.49 U 0.669 0.148 U 1.02

< 0.0500

< 0.0700 0.891 0.891 2.48 U

-9.77 U NA 10/21/19

< 1.0

< 1.0

< 1.0

< 1.0 1.0 1.1

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.259 0.023 0.34 1.22 U 0.266 U 0.0677 U 0.264 U

< 0.050

< 0.070 0.123 J 0.123 J 3.32 U

-21.0 U NA 04/21/20

< 1.0

< 1.0 1.9

< 1.0 160 4.9

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.191 0.0674 0.43 2.89 U 0.613 0.0539 U 0.323

< 0.0500

< 0.0700 0.686 0.686 9.10 3.26 U NA W-64 11/01/18

< 1.0

< 1.0

< 1.0

< 1.0 1.5

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 3.26 20.7 49 1.91 U 0.176 U 0.0677 U 0.0908 U

< 0.0500

< 0.0700 0.14 J 0.14 J 76.3 74.7 NA 01/18/19

< 1.0

< 1.0

< 1.0

< 1.0 1.8

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 4.32 21.9 61 3.89 U 0.516 0.261 0.211

< 0.0500

< 0.0700

< 0.200

< 0.200 88.5 118 NA 10/17/19

< 1.0

< 1.0

< 1.0

< 1.0 1.3

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 4.27 16 42 4.11 U 0.0871 U 0.0256 U 0.0239 U

< 0.050

< 0.070

< 0.200

< 0.200 70.3 81.9 NA 04/20/20

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 4.1 16.1 40 5.82 0.616 0.0329 U 0.226

< 0.0500

< 0.0700 0.28 0.28 0.969 U

-0.556 U NA W-65 10/31/18

< 25

< 25

< 25

< 25 210 93

< 10

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 3.08 0.0185 0.39 2.49 U 0.115 U

-0.0134 U 0.0253 U

< 0.0500

< 0.0700

< 0.200

< 0.200 0.895 U

-7.13 U NA 01/21/19

< 5.0

< 5.0

< 5.0

< 5.0 230 94

< 5

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 1.48 0.0329 0.4 0.423 U 0.173 U 0.198 U 0.236 U

< 0.0500

< 0.0700

< 0.200

< 0.200 0.164 U

-1.51 U NA 10/17/19

< 1.0

< 1.0 13

< 1.0 220 84

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.783 0.0489 0.64 1.22 U

-0.0554 U

-0.0400 U 0.0898 U

< 0.050

< 0.070

< 0.200

< 0.200 7.14

-20.1 U NA 04/24/20

< 1.0

< 1.0 13

< 1.0 300 76

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.44 0.023 0.75 2.07 U 0.0103 U

-0.00428 U 0.0493 U

< 0.0500

< 0.0700

< 0.200

< 0.200

-1.04 U 1.19 U NA W-66 10/31/18

< 5.0

< 5.0

< 5.0

< 5.0 66

< 5.0

< 2.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 1.19 0.0687 18 0.879 U 0.0427 U 0.0129 U 0.104 U

< 0.0500

< 0.0700

< 0.200

< 0.200 1.85 U

-19.5 U NA 01/21/19

< 5.0

< 5.0

< 5.0

< 5.0 200 11

< 5

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.162 0.0231 2

1.28 U 0.303 U 0.179 U 0.331

< 0.0500

< 0.0700

< 0.200

< 0.200 2.40 U

-7.73 U NA 10/17/19

< 5.0

< 5.0 22

< 5.0 480 8.5

< 5.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.076 0.0336 1.5

-0.144 U 0.0479 U 0.00220 U 0.0800 U

< 0.050

< 0.070

< 0.200

< 0.200 3.33 U

-10.5 U NA 04/24/20

< 1.0

< 1.0 18

< 1.0 360 7.6

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.047 0.0177 1.5 0.673 U

-0.00661 U 0.0452 U 0.0178 U

< 0.0500

< 0.0700

< 0.200

< 0.200 3.87

-0.0286 U NA W-67 11/01/18

< 1.0

< 1.0 1.7

< 1.0 41 8.4

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.063 1.26 17 0.823 U 0.0482 U 0.101 U 0.239

< 0.0500

< 0.0700

< 0.200

< 0.200 73.4 82.9 NA 01/18/19

< 1.0

< 1.0 1.6

< 1.0 38 8.1

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.008 1.41 17 0.640 U 0.261 U 0.314 0.410

< 0.0500

< 0.0700

< 0.200

< 0.200 67.5 114 NA 10/18/19

< 1.0

< 1.0 1.5

< 1.0 49 8.4

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.01 1.31 14 0.945 U

-0.0325 U 0 U 0.0343 U

< 0.050

< 0.070

< 0.200

< 0.200 65.3 84.3 NA 04/21/20

< 1.0

< 1.0 1.7

< 1.0 46 8.4

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.018 2.01 16 3.78 U

-0.0443 U

-0.000237 U 0.0474 U

< 0.0500

< 0.0700

< 0.200

< 0.200 55.6 86.5 NA W-68 11/06/18

< 1.0

< 1.0

< 1.0

< 1.0 130 2.7

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.047 0.0264 3.4 2.95 U 0.123 U 0.0386 U

-0.00823 U

< 0.0500

< 0.0700 0.0802 J 0.0802 J 0.641 U

-10.3 U NA 01/31/19

< 1.0

< 1.0

< 1.0

< 1.0 150 2.5

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.009 0.0219 3.3 1.23 U 0.440 0.368 0.398

< 0.0500

< 0.0700

< 0.200

< 0.200 0.645 U

-0.519 U NA 10/22/19

< 1.0

< 1.0

< 1.0

< 1.0 110 1.8

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.02 0.0143 3.0 0.922 U 0.204 U 0.0452 U 0.0102 U

< 0.050

< 0.070

< 0.200

< 0.200 2.33 U

-31.1 U NA 04/20/20

< 1.0

< 1.0

< 1.0

< 1.0 110 1.7

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.089 0.0452 2.9 3.23 U 0.0317 U

-0.000204 U

-0.0170 U

< 0.0500

< 0.0700

< 0.200

< 0.200 5.89 0.409 U NA W-69 10/23/19

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.022 0.0341 0.16 2.31 U 0.366 0.118 U 0.201 U

< 0.050

< 0.070

< 0.200

< 0.200 1.94 U

-5.87 U NA 04/16/20

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80

< 0.1 0.0307 0.23 0.581 U

-0.00505 U 0.0242 U 0.00948 U

< 0.0500

< 0.0700

< 0.200

< 0.200 0.885 U

-0.314 U NA W-70 10/23/19

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80

< 0 0.0077 1.4 0.0198 U 0.188 U

-0.0415 U 0.0615 U

< 0.050

< 0.070

< 0.200

< 0.200 1.37 U 21.4 U NA 04/16/20

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80

< 0.1 0.0125 1.5 5.42

-0.0591 U

-0.0744 U

-0.0123 U

< 0.0500

< 0.0700

< 0.200

< 0.200 1.95 U

-0.552 U NA W-71 10/23/19

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.084 0.0149 0.021 0.983 U 0.228 U 0.0113 U 0.0743 U

< 0.050

< 0.070 0.165 J 0.165 J 8.11 12.2 U NA 04/16/20

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80

< 0.1 0.0156

< 0.02 4.72

-0.0215 U

-0.000314 U 0.0375 U

< 0.0500

< 0.0700 0.0765 J 0.0765 J 4.39 1.27 U NA W-72 10/04/19

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.116 0.275 1.5 1.05 U 0.125 U

-0.0117 U 0.0205 U

< 0.050

< 0.070 0.095 J 0.095 J 2.74 U

-17.1 U NA 04/03/20

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 1.08 0.0322 6.3 2.98 U 1.17 0.0265 U 0.162

< 0.0500 0.021 J 0.667 0.688 8.51 1.33 U NA Page 18 of 20

Table C-1 Summary of Historical Groundwater Analytical Results (2015-2020)

Westinghouse Columbia Fuel Fabrication Facility Hopkins, South Carolina AECOM Project No. 60595649 Carbon Disulfide ug/L Chloroform ug/L cis-1,2-Dichloroethene ug/L Ethylbenzene ug/L Tetrachloroethene ug/L Trichloroethene ug/L Vinyl Chloride ug/L 1,1'-Biphenyl ug/L 2-Methylnaphthalene ug/L Acenaphthene ug/L Carbazole ug/L Fluorene ug/L Naphthalene ug/L Phenanthrene ug/L Fluoride mg/L Ammonia NH3(N) mg/L Nitrate NO3 mg/L Gross Alpha pCi/L Isotopic Uranium 233/234 pCi/L Isotopic Uranium 235/236 pCi/L Isotopic Uranium 238 (HASL300) pCi/L Isotopic Uranium 234 ug/L Isotopic Uranium 235 ug/L Isotopic Uranium 238 ug/L Total Uranium ug/L Gross Beta pCi/L Tc-99 pCi/L Tritium pCi/L 70 700 5

5 2

4 10 15

• 30 50

• 900 20,000 Well Date Radionuclides Inorganics MCL/Action Level VOCs SVOCs W-73 10/04/19

< 1.0

< 1.0 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.071 0.0167 2.0 0.241 U

-0.00420 U 0.0655 U 0.121 U

< 0.050

< 0.070 0.0831 J 0.0831 J 1.85 U

-23.0 U NA 04/03/20

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80

< 0.1 0.0383 1.4

-2.20 U 0.155 U 0.0780 U

-0.0258 U

< 0.0500

< 0.0700 0.0873 J 0.0873 J 2.27 U

-1.62 U NA W-74 10/09/19

< 1.0

< 1.0 1.9

< 1.0 19 4.5

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.019 0.159 4.9

-0.595 U 0.111 U 0.00238 U 0.0963 U

< 0.050

< 0.070

< 0.200

< 0.200 1.29 U 11.5 U NA 04/08/20

< 1.0

< 1.0 1.6

< 1.0 19 4.2

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.01 0.0129 5.4

-0.164 U

-0.0540 U

-0.0593 U

-0.00979 U

< 0.0500

< 0.0700

< 0.200

< 0.200 2.38 U

-1.38 U NA W-75 10/09/19

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.109 0.391 0.063 2.10 U 0.0135 U 0.0780 U 0.00143 U

< 0.050

< 0.070

< 0.200

< 0.200 3.89 U

-15.8 U NA 04/08/20

< 1.0

< 1.0

< 1.0

< 1.0 1

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.068 0.268 1.6 1.80 U

-0.0429 U

-0.0219 U 0.00834 U

< 0.0500

< 0.0700

< 0.200

< 0.200 3.68

-1.17 U NA W-76 10/05/19

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0 63

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 1.45 0.0154 9.8 2.77 U 1.60

-0.0126 U 0.354

< 0.050 0.0308 J 0.915 0.946 6.88

-14.6 U NA 04/14/20

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0 44

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 1.4 0.0163 8.7 12.7 4.92 0.196 0.830

< 0.0500 0.0999 2.87 2.97 4.56 U

-0.741 U NA W-77 10/06/19

< 1.0 11

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 9.21 7.11 12 865 511 26.0 81.0 0.089 10.1 237 247 111 101 NA 04/14/20

< 1.0 11

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 7.39 17 20 399 591 28.5 88.7 0.104 11.2 253 264 41.7 5.10 NA W-78 10/05/19

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 13.4 0.0271 3.5

-0.146 U 0.0921 U 0.0466 U 0.105 U

< 0.050

< 0.070 0.0933 J 0.0933 J 4.12 U

-6.50 U NA 04/14/20

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 11.3 0.0286 4.4 1.82 U 0.0631 U 0.0946 U 0.0207 U

< 0.0500

< 0.0700 0.203 0.203 2.97 U 0.0509 U NA W-79 10/07/19

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 2.4 0.0146 4.0 2.99 U 0.0539 U

-0.0112 U 0.115 U

< 0.050

< 0.070 0.0892 J 0.0892 J 5.90 3.52 U NA 04/13/20

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.323 0.0099 5.1 0.312 U

-0.0423 U

-0.00965 U 0.0449 U

< 0.0500

< 0.0700

< 0.200

< 0.200 5.06 0.135 U NA W-80 10/06/19

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 1.57 0.0927 8.3 1.30 U 0.154 U 0.0254 U 0.0695 U

< 0.050

< 0.070 0.151 J 0.151 J 7.29 2.56 U NA 04/14/20

< 1.0 2.3

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.121 0.0158 16 3.43 0.167 U 0.0226 U 0.106 U

< 0.0500

< 0.0700 0.177 J 0.177 J 9.42

-1.32 U NA W-81 10/08/19

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.042 0.0762 3.1

-0.177 U 0.00840 U

-0.0482 U 0.112 U

< 0.050

< 0.070 0.0728 J 0.0728 J 1.23 U

-11.9 U NA 04/14/20

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.067 0.381 1.4 5.29 0.349 0.0590 U 0.150 U

< 0.0500

< 0.0700 0.393 0.393 8.64

-0.0743 U NA W-82 10/08/19

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.046 0.0275 0.99 1.37 U 0.0453 U 0 U 0.140 U

< 0.050

< 0.070 0.151 J 0.151 J 4.82

-1.54 U NA 04/14/20

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.041 0.0209 1.8 2.27 U 0.0344 U 0.00931 U 0.00738 U

< 0.0500

< 0.0700

< 0.200

< 0.200 6.49

-1.65 U NA W-83 10/08/19 2.1 1.3

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.079 0.0099 0.76 0.300 U 0.603 0.161 U

-0.0584 U

< 0.050

< 0.070

< 0.200

< 0.200 2.75 U 0.914 U NA 04/13/20

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.104 0.0099 0.8 1.90 U 0.0991 U 0.0149 U 0.0242 U

< 0.0500

< 0.0700

< 0.200

< 0.200 3.68 U

-2.64 U NA W-84 10/08/19

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.087 0.0119

< 0.020

-0.286 U 0.0661 U 0.0491 U

-0.00952 U

< 0.050

< 0.070 0.0704 J 0.0704 J 3.97 U

-9.22 U NA 04/13/20

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.107 0.0202

< 0.02 4.27 0.0943 U 0.00983 U 0.0161 U

< 0.0500

< 0.0700

< 0.200

< 0.200 6.12

-1.79 U NA W-85 10/23/19

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.23 0.03 0.039 1.42 U 0.0494 U 0.0621 U 0.0502 U

< 0.050

< 0.070

< 0.200

< 0.200 1.23 U 19.3 U NA 04/28/20

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.217 0.129 0.023 1.74 U

-0.0346 U 0.0349 U 0.00884 U

< 0.0500

< 0.0700

< 0.200

< 0.200 3.47

-0.860 U NA W-86 10/23/19

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.511 0.0073

< 0.020 0.317 U 0.125 U 0.130 U 0.137 U

< 0.050

< 0.070

< 0.200

< 0.200 7.12 8.88 U NA 04/28/20

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.473 0.0137

< 0.02 1.90 U 0.0841 U 0.00967 U 0.0315 U

< 0.0500

< 0.0700

< 0.200

< 0.200 0.0942 U

-0.335 U NA W-87 10/02/19

< 1.0

< 1.0 2.0

< 1.0 38 11

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.278 0.0127 0.055 1.68 U 0.175 U 0.00163 U 0.151 U

< 0.050

< 0.070 0.457 0.457 4.92 0.787 U NA 04/15/20

< 1.0

< 1.0

< 1.0

< 1.0 41 8.6

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.239 0.0306 0.045 3.87 0.0251 U

-0.0151 U

-0.000241 U < 0.0500

< 0.0700 0.139 J 0.139 J 1.57 U

-0.866 U NA W-88 10/22/19

< 1.0

< 1.0

< 1.0

< 1.0 4.1

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.012 0.0127 4.5 2.50 U 0.107 U 0.0449 U 0.185 U

< 0.050

< 0.070

< 0.200

< 0.200 2.05 U 6.34 U NA 04/17/20

< 1.0

< 1.0

< 1.0

< 1.0 3.9

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80

< 0.1 0.0157 4.3 3.63 0.0393 U

-0.0131 U

-0.0108 U

< 0.0500

< 0.0700

< 0.200

< 0.200 4.16 U 1.15 U NA W-89 10/22/19

< 1.0

< 1.0

< 1.0

< 1.0 2.1

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.011 0.0132 2.5 0.498 U 0.209 U

-0.0110 U

-0.0178 U

< 0.050

< 0.070

< 0.200

< 0.200

-0.799 U 27.5 U NA 04/17/20

< 1.0

< 1.0

< 1.0

< 1.0 6.7

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.001 0.0336 2.5 1.61 U

-0.0349 U 0.0379 U

-0.0106 U

< 0.0500

< 0.0700

< 0.200

< 0.200 1.25 U

-1.06 U NA W-90 10/22/19

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.039 0.0147 2.3 0.889 U 0.0370 U 0.0653 U

-0.0139 U

< 0.050

< 0.070

< 0.200

< 0.200 23.1 6.68 U NA 04/17/20

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80

< 0.1 0.0174 1.4 3.85

-0.0455 U

-0.0134 U

-0.0428 U

< 0.0500

< 0.0700

< 0.200

< 0.200 2.69 U

-0.242 U NA W-92 10/10/19

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.099 3.19 0.029 1.58 U 0.0426 U

-0.0270 U 0.0765 U

< 0.050

< 0.070

< 0.200

< 0.200 3.78 U

-10.2 U NA 04/27/20

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.1 4.11

< 0.02 0.372 U 0.0370 U 0.0378 U

-0.0314 U

< 0.0500

< 0.0700

< 0.200

< 0.200 2.51 U 2.49 U NA W-93 10/06/19

< 1.0

< 1.0

< 1.0

< 1.0 24 2.8

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.043 0.0324 5.3 3.06 0.115 U 0.0644 U 0.0900 U

< 0.050

< 0.070

< 0.200

< 0.200 8.18

-29.0 U NA 04/14/20

< 1.0

< 1.0

< 1.0

< 1.0 28 3.6

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.017 0.0139 4.6 1.12 U

-0.00215 U 0.0396 U 0.0238 U

< 0.0500

< 0.0700

< 0.200

< 0.200 3.82 U

-0.623 U NA W-94 10/15/19

< 1.0

< 1.0 5.3

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.043 0.246

< 0.020 1.14 U 0.0614 U

-0.0102 U 0.0262 U

< 0.050

< 0.070

< 0.200

< 0.200 2.48 U 20.4 U NA 04/24/20

< 1.0

< 1.0 5.6

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.043 0.245

< 0.02 0.640 U 0.129 U

-0.0187 U

-0.0524 U

< 0.0500

< 0.0700

< 0.200

< 0.200 0.552 U

-1.04 U NA W-95 10/15/19

< 1.0

< 1.0 4.3

< 1.0

< 1.0

< 1.0 2.9

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.077 0.145 0.024 0.695 U 0.0378 U 0.0692 U 0.0560 U

< 0.050

< 0.070 0.114 J 0.114 J 0.814 U 2.35 U NA 04/24/20

< 1.0

< 1.0 3.7

< 1.0

< 1.0

< 1.0 2.9

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.05 0.174 0.037 1.22 U 0.108 U 0.0369 U 0.00597 U

< 0.0500

< 0.0700

< 0.200

< 0.200 1.90 U

-0.108 U NA Page 19 of 20

Table C-1 Summary of Historical Groundwater Analytical Results (2015-2020)

Westinghouse Columbia Fuel Fabrication Facility Hopkins, South Carolina AECOM Project No. 60595649 Carbon Disulfide ug/L Chloroform ug/L cis-1,2-Dichloroethene ug/L Ethylbenzene ug/L Tetrachloroethene ug/L Trichloroethene ug/L Vinyl Chloride ug/L 1,1'-Biphenyl ug/L 2-Methylnaphthalene ug/L Acenaphthene ug/L Carbazole ug/L Fluorene ug/L Naphthalene ug/L Phenanthrene ug/L Fluoride mg/L Ammonia NH3(N) mg/L Nitrate NO3 mg/L Gross Alpha pCi/L Isotopic Uranium 233/234 pCi/L Isotopic Uranium 235/236 pCi/L Isotopic Uranium 238 (HASL300) pCi/L Isotopic Uranium 234 ug/L Isotopic Uranium 235 ug/L Isotopic Uranium 238 ug/L Total Uranium ug/L Gross Beta pCi/L Tc-99 pCi/L Tritium pCi/L 70 700 5

5 2

4 10 15

• 30 50

• 900 20,000 Well Date Radionuclides Inorganics MCL/Action Level VOCs SVOCs W-96 10/11/19

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.111 0.228 0.054 2.51 U 0.0695 U 0.108 U 0.0719 U

< 0.050

< 0.070

< 0.200

< 0.200 4.36

-1.25 U NA 04/24/20

< 1.0

< 1.0

< 1.0

< 1.0 1.2

< 1.0

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.059 0.165

< 0.02 0.667 U 0.0173 U

-0.000182 U 0.110 U

< 0.0500

< 0.0700

< 0.200

< 0.200 3.11 U 0.00377 U NA W-97 10/11/19

< 1.0

< 1.0

< 1.0

< 1.0 4.3 1.2

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.375 4.89 3.4 0.168 U 0.106 U 0.0403 U 0.0495 U

< 0.050

< 0.070

< 0.200

< 0.200 11.0 10.3 U NA 04/24/20

< 1.0

< 1.0

< 1.0

< 1.0 9.8 2

< 1.0

< 4.0

< 0.80

< 0.80

< 4.0

< 0.80

< 0.80

< 0.80 0.233 2.32 6

6.24 0.0625 U 0.00869 U

-0.0452 U

< 0.0500

< 0.0700

< 0.200

< 0.200 53.8 88.3 NA Notes:

ug/L - Micrograms per liter mg/L - Milligrams per liter pCi/L - Picocuries per liter MCL - Maximum Contaminant Level

• - site specific action level Tc Technetium-99 NA - Not analyzed U - Analyte was not detected above the minimun detectable level, concentration, or activity J - Estimated result is less than the practical quantitation limit and greater than the method detection limit Page 20 of 20

2019/2020 Annual Groundwater Monitoring Report Project number: 60595649 Prepared for: Westinghouse Electric Company, LLC AECOM Appendix D - Trend Plots

0 100 200 300 400 500 600 700 800 900 1000 1100 1200 1300 Oct14 Jan15 Apr15 Jul15 Oct15 Jan16 Apr16 Jul16 Oct16 Jan17 Apr17 Jul17 Oct17 Jan18 Apr18 Jul18 Oct18 Jan19 Apr19 Jul19 Oct19 Jan20 Apr20 Concentration(mg/L)

SampleDate W7 W18R W30 MCL 0

10 20 30 40 50 60 70 80 90 Oct14 Jan15 Apr15 Jul15 Oct15 Jan16 Apr16 Jul16 Oct16 Jan17 Apr17 Jul17 Oct17 Jan18 Apr18 Jul18 Oct18 Jan19 Apr19 Jul19 Oct19 Jan20 Apr20 Concentration(mg/L)

SampleDate W10 W14 W17 W26 W29 W38 W43 W41R W47 MCL

0.0 1.0 2.0 3.0 4.0 5.0 6.0 7.0 8.0 9.0 10.0 11.0 12.0 Oct14 Jan15 Apr15 Jul15 Oct15 Jan16 Apr16 Jul16 Oct16 Jan17 Apr17 Jul17 Oct17 Jan18 Apr18 Jul18 Oct18 Jan19 Apr19 Jul19 Oct19 Jan20 Apr20 Concentration(mg/L)

SampleDate FigureD2 FluorideConcentrationTrends W7 W13R W14 W16 W17 W18R W29 W30 W47 MCL

0 50 100 150 200 Oct18 Jan19 Apr19 Jul19 Oct19 Jan20 Apr20 Concentration(ug/L)

SampleDate FigureD3 UraniumConcentrationTrends W7A W10 W14 W17 W18R W22 W28 W29 W30 W55 W56 W58 W59 W64 MCL

0 1000 2000 3000 4000 Jan15 Apr15 Jul15 Oct15 Jan16 Apr16 Jul16 Oct16 Jan17 Apr17 Jul17 Oct17 Jan18 Apr18 Jul18 Oct18 Jan19 Apr19 Jul19 Oct19 Jan20 Apr20 Concentration(pCi/L)

SampleDate FigureD4 Technetium99ConcentrationTrends W6 W7A W10 W11 W15 W17 W18 W30 W46 W47 W67 MCL

2019/2020 Annual Groundwater Monitoring Report Project number: 60595649 Prepared for: Westinghouse Electric Company, LLC AECOM Appendix E - DHEC Correspondence

From:

Joyner, Diana P To:

Amick, Byron

Subject:

RE: NPDES Permit Groundwater Sampling Request-Spring 2020 Date:

Friday, February 28, 2020 12:04:41 PM Attachments:

image002.png Thank you Byron.

Diana

Diana P. Joyner joynerdp@westinghouse.com 803.647.1920 (office) l 803.497.7062 (mobile)

From: Amick, Byron <AMICKBM@dhec.sc.gov>

Sent: Thursday, February 27, 2020 2:56 PM To: Joyner, Diana P <joynerdp@westinghouse.com>; Leypoldt, Dustin <leypold@dhec.sc.gov>; Moores, Carolyn T.

<mooresct@dhec.sc.gov>; Rippy, Crystal <RIPPYCD@dhec.sc.gov>

Cc: Hindman, Melanie <Hindmamh@dhec.sc.gov>; Johnson, Sonya C. <JOHNSOSC@dhec.sc.gov>; Jones, Samuel M.

<jonessm1@dhec.sc.gov>; Parr, Nancy B. <parrnb@westinghouse.com>; Crews, Randy E <crewsre@westinghouse.com>;

Logsdon, Cynthia J. <logsdocj@westinghouse.com>; Grant, Jeremy <jeremy.grant@aecom.com>

Subject:

RE: NPDES Permit Groundwater Sampling Request-Spring 2020

[External Email]

After consulting with the Departments Groundwater Protection and Agricultural Permitting Section, we hereby approve of your request to move the upcoming round of groundwater sampling requirements in the current NPDES Permit (SC0001848) from December, January or February to April, May and June of this year to match the requirements of the Consent Agreement.

I apologized for the delay in responding.

Byron M. Amick Environmental Engineering Associate Water Facilities Permitting Division S.C. Dept. of Health & Environmental Control Office: (803) 898-4236 Connect: www.scdhec.gov [scdhec.gov] Facebook [facebook.com] Twitter [twitter.com]

From: Joyner, Diana P [1]

Sent: Wednesday, January 29, 2020 2:10 PM To: Amick, Byron <AMICKBM@dhec.sc.gov>; Leypoldt, Dustin <leypold@dhec.sc.gov>; Moores, Carolyn T.

<mooresct@dhec.sc.gov>

Cc: Hindman, Melanie <Hindmamh@dhec.sc.gov>; Johnson, Sonya C. <JOHNSOSC@dhec.sc.gov>; Jones, Samuel M.

<jonessm1@dhec.sc.gov>; Parr, Nancy B. <parrnb@westinghouse.com>; Crews, Randy E <crewsre@westinghouse.com>;

logsdocj@westinghouse.com; Grant, Jeremy <jeremy.grant@aecom.com>

Subject:

NPDES Permit Groundwater Sampling Request-Spring 2020 Importance: High

• • • Caution. This is an EXTERNAL email. DO NOT open attachments or click links from unknown senders or unexpected email. ***

Carolyn, Dustin and Byron-Per my in-person conversation with Byron on January 9th, 2020, the Westinghouse site is seeking concurrence with the department on pending groundwater well sample collection for the first semi-annual cycle in 2020. This request is similar to the one you approved on August 26, 2019.

Current Sampling Commitments: Existing Permit, Draft Permit, Consent Agreement

Per the sites existing permit Part III, Section C, measurement frequency shall be semi-annual.

Samples shall be taken in the winter months of December, January or February, and in the summer months of June, July or August and the results shall be included in the annual report submitted to DHEC by September 28th of the same year. The annual report must reference Site ID #00456.

Per the current draft permit, Part III Section C b. measurement frequency shall be semiannual according to the table below:

Per the sites consent agreement RI Work Plan timeline, the existing 20 NPDES wells, 41other site wells (not currently NPDES permit wells), and newly installed RI Work Plan wells (29) for a total of 90 wells were last sampled in October 2019. The results of this sampling campaign were shared with department representatives from two bureaus on January 9, 2020. The audience included Byron Amick, Dusty Leypold, and Carolyn Moores from the NPDES and Groundwater divisions. The formal report will be submitted to the department no later than February 28, 2020.

The time frames for the above listed commitments are not aligned and in their present state would require the site to conduct 2 separate groundwater sampling campaigns over a 4-6 month period. As Westinghouse transitions from an annual to a semi-annual reporting frequency, we do not feel two site-wide campaigns in such a short time frame would be beneficial.

Westinghouse would like to propose that the current permit requirement to collect samples in the winter months of December, January, or February be stayed so that sampling can be conducted in accordance with the timeline of the draft permit (i.e. April, May and June). If approved, Westinghouse intends to schedule the sampling for April of 2020.

The Departments consideration of this request is most appreciated.

Diana

Diana P. Joyner Principal Environmental Engineer Westinghouse Electric Company, LLC Columbia Fuel Fabrication Facility joynerdp@westinghouse.com 803.647.1920 (office) l 803.497.7062 (mobile)

This e-mail may contain proprietary information of the sending organization. Any unauthorized or improper disclosure, copying, distribution, or use of the contents of this e-mail and attached document(s) is prohibited. The information contained in this e-mail and attached document(s) is intended only for the personal and private use of the recipient(s) named above. If you have received this communication in error, please notify the sender immediately by email and delete the original e-mail and attached document(s).

This e-mail may contain proprietary information of the sending organization. Any unauthorized or improper disclosure, copying, distribution, or use of the contents of this e-mail and attached document(s) is prohibited. The information contained in this e-mail and attached document(s) is intended only for the personal and private use of the recipient(s) named above. If you have received this communication in error, please notify the sender immediately by email and delete the original e-mail and attached document(s).

From:

Joyner, Diana P To:

Moores, Carolyn T.

Subject:

RE: Westinghouse Groundwater Monitoring Report and E-Permitting Platform Date:

Friday, August 14, 2020 11:43:09 AM Attachments:

image003.png Thank you Carolyn.

I am in agreement with your summary of our conversation yesterday regarding ePermitting and the annual Groundwater report for Westinghouse.

Looking forward to hearing from you further when you have more information.

Diana

Diana P. Joyner Principal Environmental Engineer Westinghouse Electric Company, LLC Columbia Fuel Fabrication Facility joynerdp@westinghouse.com 803.647.1920 (office) l 803.497.7062 (mobile)

From: Moores, Carolyn T. <mooresct@dhec.sc.gov>

Sent: Friday, August 14, 2020 11:13 AM To: Joyner, Diana P <joynerdp@westinghouse.com>

Subject:

Re: Westinghouse Groundwater Monitoring Report and E-Permitting Platform

[External Email]

Good morning,

Per our conversation yesterday, I wanted to let you know I am checking on the schedule status that is in epermitting for Westinghouse. Your concerns were that the 'renewed' permit schedule was entered into epermitting while your facility is still officially operating under the 'old' permit schedules. The schedule in epermitting should reflect the conditions of the current permit and then be changed to reflect the renewed permit when it goes into effect. I will investigate this issue and get back with you soon, hopefully next week.

Submitting the Groundwater Data via ePermitting is acceptable and preferable.As we discussed in our telephone conversation, this is a transition phase and as I understand at this point in time, the Bureau of Water can still accept hard copies or PDF's but the Bureau is trying hard to get everyone on board with the ePermitting system as soon as possible.

I will be checking into the status of the formats that can be accepted in the epermitting drag and drop submission box. This is known to be useful for dropping lab data sheets in pdf format to support the groundwater monitoring report submissions. We are hoping it can also be useful for dropping a spreadsheet-style data file that could accommodate the need for high volume well and analyte samplereporting, such as an excel or comma delineated format. I will also get back to you on that, but it may not be as quickly as next week.

It is understood that when the file drop of that sort becomes available, that Westinghouse would then load the groundwater data from this year into the epermitting database.

Will be in touch on these issues,

Carolyn Moores

From: Joyner, Diana P <joynerdp@westinghouse.com>

Sent: Wednesday, August 12, 2020 3:43 PM To: Moores, Carolyn T. <mooresct@dhec.sc.gov>

Subject:

RE: Westinghouse Groundwater Monitoring Report and E-Permitting Platform

• • • Caution. This is an EXTERNAL email. DO NOT open attachments or click links from unknown senders or unexpected email. ***

Sounds great. Talk to you then!

Diana

From: Moores, Carolyn T. <mooresct@dhec.sc.gov>

Sent: Wednesday, August 12, 2020 3:39 PM To: Joyner, Diana P <joynerdp@westinghouse.com>

Subject:

Re: Westinghouse Groundwater Monitoring Report and E-Permitting Platform

[External Email]

Diane,

Let's shoot for the early window, I can give you a call in the morning. I must caution you that I am no expert in epermitting but I will do my best to help or find answers or people who can answer your questions.

Carolyn From: Joyner, Diana P <joynerdp@westinghouse.com>

Sent: Wednesday, August 12, 2020 3:33 PM To: Moores, Carolyn T. <mooresct@dhec.sc.gov>

Subject:

RE: Westinghouse Groundwater Monitoring Report and E-Permitting Platform

• • • Caution. This is an EXTERNAL email. DO NOT open attachments or click links from unknown senders or unexpected email. ***

That would be great Carolyn. Im free from 8-9:30 and then again at 11:30.

Looking forward to hearing from you.

Diana

From: Moores, Carolyn T. <mooresct@dhec.sc.gov>

Sent: Wednesday, August 12, 2020 3:11 PM To: Joyner, Diana P <joynerdp@westinghouse.com>

Subject:

Re: Westinghouse Groundwater Monitoring Report and E-Permitting Platform

[External Email]

Diana,

I was in meetings this morning when I received this email and am currently still in meetings. Perhaps we can try tomorrow?

Carolyn From: Joyner, Diana P <joynerdp@westinghouse.com>

Sent: Wednesday, August 12, 2020 10:53 AM To: Moores, Carolyn T. <mooresct@dhec.sc.gov>

Cc: Leypoldt, Dustin <leypold@dhec.sc.gov>; Parr, Nancy B. <parrnb@westinghouse.com>; Williams, Charles J.

<williacj@dhec.sc.gov>

Subject:

RE: Westinghouse Groundwater Monitoring Report and E-Permitting Platform

• • • Caution. This is an EXTERNAL email. DO NOT open attachments or click links from unknown senders or unexpected email. ***

Carolyn-Could we please have a follow-up discussion later today about the correspondence below?

I have a fairly open schedule for the remainder of the day except between 3-4 pm.

My contact number is 803.497.7062.

I look forward to hearing from you.

Thanks, Diana

From: Moores, Carolyn T. <mooresct@dhec.sc.gov>

Sent: Wednesday, June 24, 2020 11:35 AM To: Joyner, Diana P <joynerdp@westinghouse.com>

Cc: Leypoldt, Dustin <leypold@dhec.sc.gov>; Parr, Nancy B. <parrnb@westinghouse.com>; Williams, Charles J.

<williacj@dhec.sc.gov>

Subject:

Re: Westinghouse Groundwater Monitoring Report and E-Permitting Platform

[External Email]

Diana,

Thank you for reaching out to us with your questions on our new online platform, ePermitting. Do not worry about the overdue status showing in epermitting right now. When you electronically submit sample results into the system, it will be corrected.

We will be sending a letter out soon with more information about the system. However, in the interim, the groundwater samples that were due January 28, 2020 will need to be submitted electronically. Training for navigating and using theePermittingwebsite is available on the Department website atwww.scdhec.gov/ePermitting/training [scdhec.gov].

To complete GMRs the following information will be required in addition to entering the sample analysis results:

1. Lab sheets in pdf format

2. Monitoring well elevation within 0.01 ft msl in order to report water table elevation

3. Location of all monitoring wells

I checked your groundwater monitoring schedules in ePermitting, and it appears they are showing up correctly according to the working permit. The working permit is for semi-annual submissions due January 28 and July

28. As you know, the January 28 submission is showing as overdue (this will be corrected when you submit electronically) and the July 28 submission is shown in the right panel in the "Upcoming" column. Currently, you will not have access to submit the midyear sample until 30 days prior, which is stated with the schedule information.

As far as the upcoming permit renewal, it is my understanding that this will also be semi-annual, although the dates have been adjusted to accommodate the remedial investigation requirements to avoid duplicating work.

The schedules in ePermitting will be adjusted when the new permit takes effect.

If you have any more questions, feel free to contact me and we can work through this transition to online submissions.

Thank you,

Carolyn Moores

From: Joyner, Diana P <joynerdp@westinghouse.com>

Sent: Wednesday, June 24, 2020 12:25 AM To: Moores, Carolyn T. <mooresct@dhec.sc.gov>; Leypoldt, Dustin <leypold@dhec.sc.gov>

Cc: Amick, Byron <AMICKBM@dhec.sc.gov>; Parr, Nancy B. <parrnb@westinghouse.com>;

logsdocj@westinghouse.com <logsdocj@westinghouse.com>

Subject:

Westinghouse Groundwater Monitoring Report and E-Permitting Platform

• • • Caution. This is an EXTERNAL email. DO NOT open attachments or click links from unknown senders or unexpected email. ***

Carolyn and Dustin-Hello. I hope that this email finds you both well. I wanted to reach out to you both regarding my sites groundwater monitoring report as it relates to the e-permitting program.

Westinghouse recently received the documentation from DHEC to initiate the e-permitting program for our site. I was recently established as an administrator and began exploring the e-permitting platform. While navigating through our files, I noticed that we have an overdue groundwater report in our dashboard. In addition, we have an upcoming GMR due July 28, 2020. Please see the screenshot below.

I understand from a separate discussion with Byron Amick that this overdue alert may be a global issue that the department is working on. I wanted to confirm this information and see if there is anything Westinghouse needs to do in the interim while the global issue is being resolved. Secondly, I wanted to ask that you check the frequency of our current reporting requirement in the e-permitting system. It appears that our draft permit criteria was entered for the

GMR due dates (semi-annual) as opposed to our existing permit criteria (annual).

I look forward to hearing from you.

Thanks, Diana

Diana P. Joyner Principal Environmental Engineer Westinghouse Electric Company, LLC Columbia Fuel Fabrication Facility joynerdp@westinghouse.com 803.647.1920 (office) l 803.497.7062 (mobile)

This e-mail may contain proprietary information of the sending organization. Any unauthorized or improper disclosure, copying, distribution, or use of the contents of this e-mail and attached document(s) is prohibited. The information contained in this e-mail and attached document(s) is intended only for the personal and private use of the recipient(s) named above. If you have received this communication in error, please notify the sender immediately by email and delete the original e-mail and attached document(s).

This e-mail may contain proprietary information of the sending organization. Any unauthorized or improper disclosure, copying, distribution, or use of the contents of this e-mail and attached document(s) is prohibited. The information contained in this e-mail and attached document(s) is intended only for the personal and private use of the recipient(s) named above. If you have received this communication in error, please notify the sender immediately by email and delete the original e-mail and attached document(s).

This e-mail may contain proprietary information of the sending organization. Any unauthorized or improper disclosure, copying, distribution, or use of the contents of this e-mail and attached document(s) is prohibited. The information contained in this e-mail and attached document(s) is intended only for the personal and private use of the recipient(s) named above. If you have received this communication in error, please notify the sender immediately by email and delete the original e-mail and attached document(s).

This e-mail may contain proprietary information of the sending organization. Any unauthorized or improper disclosure, copying, distribution, or use of the contents of this e-mail and attached document(s) is prohibited. The information contained in this e-mail and attached document(s) is intended only for the personal and private use of the recipient(s) named above. If you have received this communication in error, please notify the sender immediately by email and delete the original e-mail and attached document(s).

This e-mail may contain proprietary information of the sending organization. Any unauthorized or improper disclosure, copying, distribution, or use of the contents of this e-mail and attached document(s) is prohibited. The information contained in this e-mail and attached document(s) is intended only for the personal and private use of the recipient(s) named above. If you have received this communication in error, please notify the sender immediately by email and delete the original e-mail and attached document(s).

This e-mail may contain proprietary information of the sending organization. Any unauthorized or improper disclosure, copying, distribution, or use of the contents of this e-mail and attached document(s) is prohibited. The information contained in this e-mail and attached document(s) is intended only for the personal and private use of the recipient(s) named above. If you have received this communication in error, please notify the sender immediately by email and delete the original e-mail and attached document(s).

This e-mail may contain proprietary information of the sending organization. Any unauthorized or improper disclosure, copying, distribution, or use of the contents of this e-mail and attached document(s) is prohibited. The information contained in this e-mail and attached document(s) is intended only for the personal and private use of the recipient(s) named above. If you have received this communication in error, please notify the sender immediately by email and delete the original e-mail and attached document(s).

This e-mail may contain proprietary information of the sending organization. Any unauthorized or improper disclosure, copying, distribution, or use of the contents of this e-mail and attached document(s) is prohibited. The information contained in this e-mail and attached document(s) is intended only for the personal and private use of the recipient(s) named above. If you have received this communication in error, please notify the sender immediately by email and delete the original e-mail and attached document(s).

2019/2020 Annual Groundwater Monitoring Report Project number: 60595649 Prepared for: Westinghouse Electric Company, LLC AECOM aecom.com