ML19283A811
| ML19283A811 | |
| Person / Time | |
|---|---|
| Site: | Westinghouse |
| Issue date: | 10/16/2019 |
| From: | Jessie Quintero Environmental Review Branch |
| To: | Roman C Environmental Review Branch |
| References | |
| Download: ML19283A811 (20) | |
Text
UNITED STATES NUCLEAR REGULATORY COMMISSION WASHINGTON, D.C. 20555-0001 October 16, 2019 MEMORANDUM TO:
Cinthya I. Román, Chief Environmental Review Branch Division of Fuel Cycle Safety, Safeguards, and Environmental Review Office of Nuclear Material Safety and Safeguards FROM:
Jessie Quintero, Environmental Project Manager
/RA/
Environmental Review Branch Division of Fuel Cycle Safety, Safeguards, and Environmental Review Office of Nuclear Material Safety and Safeguards
SUBJECT:
SUMMARY
OF MAY 2019 SITE VISIT AND INFORMATION NEEDS RELATED TO THE U.S. NUCLEAR REGULATORY COMMISSIONS REVIEW OF THE ENVIRONMENTAL PROGRAM IN THE LICENSE RENEWAL APPLICATION FOR THE WESTINGHOUSE COLUMBIA FUEL FABRICATION FACILITY AND INFORMATION ABOUT RECENT EVENTS In June 2018, the U.S. Nuclear Regulatory Commission (NRC) published its Environmental Assessment (EA) and Finding of No Significant Impact (FONSI) related to the license renewal review for Westinghouse Electric Company, LLC (WEC) Columbia Fuel Fabrication Facility (CFFF). In July 2018, WEC notified the NRC of a leak that released contamination into the subsurface and that they were pursuing additional investigation into a separate leak from a contaminated wastewater pipe. Since this information emerged after the NRC published its EA and FONSI, the NRC decided to re-open its environmental review. The NRC staff developed requests for additional information (RAI) related to WECs environmental protection and decommissioning programs, dated January 18, 2019 (Agencywide Documents Access and Management System (ADAMS) Accession Number ML18308A008). In response to the RAIs, WEC submitted an updated Environmental Report (ER) and License Renewal Application (LRA)
(ADAMS Accession Number ML19088A095).
The NRC held a site visit at the CFFF on May 20-22, 2019, in support of the license renewal review. To prepare for the site visit, the NRC provided WEC with information needs. The information needs are based on new information provided in the updated ER and LRA related to environmental protections and decommissioning planning. This memo contains a summary of the site visit, the resolution of the information needs, and the documents provided by WEC to support the NRCs review.
CONTACT: Jessie Muir Quintero, NMSS/FCSE 301-415-7476
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After the site visit in May, there two incidents that occurred at the CFFFa leak from a drum storage area and a drum fire. Those events are discussed briefly, as they relate to the environmental review.
MAY 20-22, 2019 SITE VISIT
SUMMARY
The NRC staff who attended the May 2019 site visit were:
Jessie Muir Quintero (Environmental Project Manager)
Jack Gwo (Technical Reviewer, Water Resources)
John Saxton (Technical Reviewer, Soil and Water Resources)
Marilyn Diaz-Maldonado (Project Manager)
Cinthya I. Román (Branch Chief)
On Monday, May 20, 2019, the NRC attended a meeting with staff from the Congaree National Park (Park) and South Carolina Department of Health and Environmental Control (SCDHEC).
SCDHEC and NRC explained their regulatory processes and the status of the various reviews.
Dr. David Shelley of the Park provided information about regional subsurface characteristics, which are heterogeneous. He also discussed some of the sampling programs they have within the Park and offered opportunities for future monitoring with Westinghouse. Dr. Shelley committed to providing geologic maps to the NRC and SCDHEC.
After the meeting at the Park, WEC took NRC and SCDHEC staff on a tour of surface water sampling locations, the canal that connects Mill Creek segments before and after the Upper and Lower Sunset Lakes. Staff also walked along the new sentinel groundwater well monitoring locations running along the buried contaminated wastewater pipe. Staff also walked along the east lagoon.
On Tuesday, May 21, 2019, NRC, DHEC, WEC and their contractor, AECOM, discussed the newly created conceptual site model. The contractor AECOM demonstrated the tool and staff asked multiple questions about the inputs/outputs of the tool. The NRC met with SCDHEC staff to discuss the status of various SCDEHC activities.
On Wednesday, May 22, 2019, NRC and WEC discussed the remaining information needs.
The WEC and its contractor walked the NRC staff through procedure RA-433 - Environmental Remediation, referenced in Chapter 11 of the LRA.
provides the resolution of the information needs and Enclosure 2 provides figures of the groundwater wells.
SEA-LAND CONTAINER LEAK Shortly after the NRCs site visit in May, there was another event at WECs facility. In June 2019, WEC staff identified that a large storage container (intermodal or sea-land) holding drums of dry and wet combustible material had been compromised and rainwater entered the container and drums. The roof and floor of the sea-land container, as well as the drum lids had been compromised. The drums are stored in the containers while they await reprocessing. The combustible material contaminated with low levels of uranium is incinerated and the ash is
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processed to recover the uranium for use in its fuel production activities. The NRC inspectors reviewed the licensees corrective actions in June 2019 (IR 70-1151/2019-003, ADAMS Accession Number ML19212A687).
In response to this event, WEC submitted an Addendum to its Remedial Investigation Work Plan to SCDHEC to address potential contamination, investigation, and remediation. The Addendum is available on SCDHECs website at:
https://www.scdhec.gov/sites/default/files/media/document/BLWM_Westinghouse_%20Addend um%201RlWorkPlan%2006182019.pdf.
DRUM FIRE REPORTABLE EVENT Shortly after the sea-land container leak, WEC reported a drum fire to the NRC that occurred on July 12, 2019, that met NRC reporting requirements. The 55-gallon drum, which contained wet waste material contaminated with production-related material, became pressurized after being filled and put into storage. The pressurization caused the lid to come off and contents to disperse in the immediate vicinity. The contents were smoldering. The fire was extinguished without use of water. No personnel injuries were reported. More information about the event
(#EN54161) can be found on the NRCs webpage for Event Notification Reports:
https://www.nrc.gov/reading-rm/doc-collections/event-status/event/2019/20190715en.html. The WEC submitted a 30-day Follow-Up Report on August 8, 2019 (ADAMS Accession Number ML19220B682).
JULY 25, 2019 WEC SITE VISIT AND SCDHEC PUBLIC MEETING On July 25, 2019, the NRC staff went to the facility again to observe the sea-land container storage area, visit the drum storage area inside the facility, and to attend a SCDHEC public meeting. On the morning of July 25, 2019, Ms. Jessie Quintero visited the South Carolina Department of Archives and History (SCDAH) to discuss the re-opening of the environmental review and the Section 106 consultation. The NRC sent a letter to SCDAH earlier July updating the status of the environmental review (ADAMS Accession Number ML19219A242).
Ms. Quintero met with Ms. Elizabeth Johnson, Deputy State Historic Preservation Officer, and Ms. Keely Lewis, Archeologist. SCDAH reiterated that the site has never been surveyed and there is a high potential for artifacts to be present at the site. SCDAH asked about (1) commitment from WEC to notify them if structural or remains are discovered during well installation, and (2) a programmatic agreement for future land disturbance at the site.
That evening, NRC attended SCDHECs public meeting regarding its Consent Agreement with WEC. The SCDHEC created a webpage specific to WEC activities, which can be found at:
https://www.scdhec.gov/environment/ongoing-projects-updates/westinghouse. During the meeting, NRC answered questions from the community related to NRCs oversight and license renewal review.
AUGUST 1, 2019 TELECONFERENCE The WEC and NRC held a call on August 1, 2019, to discuss changes to Chapter 10 -
Environmental Program within the LRA submitted on July 11, 2019 (ADAMS Accession Number ML19192A130). WEC indicated they intended to make additional changes to the environmental monitoring program and would submit a new version of Chapter 10. On August 22, 2019, WEC submitted an updated Chapter 10 of its LRA and environmental monitoring data (ADAMS Accession Number ML19234A077).
ML19283A811 *via email OFC NMSS/REFS/ERMB NMSS/REFS/ERMB NMSS/REFS/ERMB NAME JQuintero*
AWalker-Smith*
CRoman DATE 10/08/2019 10/08/2019 10/16/2019 INFORMATION NEEDS ID#
Information Need Resolution 1
Provide someone knowledgeable to discuss changes in the March 2019 Environmental Report (ER).
The ER was revised to state that no new manufacturing buildings would be needed within the Controlled Access Area. Does this clarification imply that new facilities or land-disturbing activities may occur outside of the controlled access area (CAA), but within the site boundary (or controlled area boundary)? If so, what new buildings or construction is anticipated?
Figures 2.1-5 and 2.1-6 are not readable at current scale. Provide a readable figure showing the Controlled Access Area.
Westinghouse (WEC) stated they have no plans to construct new facilities/ buildings outside of the CAA at this time. The only activities occurring outside of the CAA are the installation of groundwater wells.
The WEC had a pre-application meeting with the U.S. Nuclear Regulatory Commission (NRC) in December 2018 (ML18352B104) about a possible license amendment to make changes to the administrative building. However, WEC is no longer pursuing that activity at this time. If WEC were to submit that license amendment request in the future, the NRC would conduct a safety and environmental review.
The WEC provided readable figures for NRCs review.
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Have someone knowledgeable to discuss protection of historic and cultural resources.
The South Carolina Archives and History Center in its response to the NRCs consultation letter said there is very high probability of significant archaeological properties, and that any future ground disturbance in previously undisturbed areas should be submitted to their office for review and comment. WEC will be installing new groundwater wells within the site boundary, in previously undisturbed areas of the site. What measures are WEC taking to ensure these activities will not affect unidentified historical or cultural resources in previously undisturbed areas of the site?
Provide copies of any procedures that address land-disturbing activities for NRC review.
The NRC reviewed configuration management procedures TA-500Columbia Manufacturing Plant Configuration Control, RA-104Regulatory Review of Configuration Change Authorization, and RAF-104-5Environmental Protection Guidelines and Checklist. TA-500 details the requirements for the evaluation, implementation, and tracking of changes to the site, structures, processes, equipment, and components at the CFFF.
Procedure RA-104 details the regulatory review of change configuration management. Procedure RA-104-5 details the environmental safety review of changes. This checklist contains the following question - Does the change potentially impact any archeological or historical sites on the WEC property, or have provisions been made for protection or mitigation in the event of an archeological or historical discovery on-site?
There are several wells and lithographic borings planned in undisturbed portions of the site. The groundwater wells and borings would result in minimal land disturbance. Before drilling, AECOM uses ground penetrating radar to check for underground utilities or subsurface anomalies. If anything is noted, AECOM will move the sample location to avoid the anomalies.
The WEC provided a copy of the procedure, Procedures Guiding the Discovery of Unanticipated Cultural Resources and Human Remains, to be followed for installation of groundwater wells, as part of its May monthly update to SCDHEC on its progress in the Consent Agreement (LTR-RAC-19-42). The procedure laid out the steps to be implemented should an anticipated discovery be made during environmental investigations: (1) stop work, mark off the area of the find; (2) notify the appropriate WEC manager, who will then notify the SHPO within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> of the discovery; (3) ensure a qualified professional archeologist examines the find to determine potential significance and will consult with SHPO; and (4) consult with the SHPO to determine a further course of action.
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13 The WEC also has a protocol for discovery of human remains and will also follow all relevant state and federal laws. If human remains are determined to be Native American, the remains will be left in place and the SHPO and appropriate Indian Nations will be consulted to develop a plan of action consistent with the Native American Graves Protection and Repatriation Act.
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Have someone knowledgeable to discuss the changes in the LRA - Chapter 11 Decommissioning.
Provide access to the Remediation Procedure referenced in LRA Ch 10.
Provide access to any documents referenced in the Remediation Procedure.
Explain how the procedure would be implemented.
Provide access to 70.25(g) files for NRC review.
The WEC created a new procedure RA-433 - Environmental Remediation and provided it for NRC staff review. This procedure lays out the decision process for when WEC would remediate or how to document the decision not to remediate. The procedure establishes entry conditions for remediationdiscovery of a past release through soil sampling; data analysis/CSM results indicate need for remediation; a detection of a contaminant that exceeds certain standards; or a new release. Action levels for contaminants for remediation are based on industrial use scenarios.
Procedure RA-433 references other documents:
- RA-136Soil Sampling and Disposal,
- RAF-136-1Soil Sampling Results for Determination of Disposal,
- RA-137Decommissioning Recordkeeping,
- RAF-137-1Decommissioning Record Keeping 10 CFR 70.25(g)(3) Required List of Areas, and
- Risk Registera tracking sheet of leaks and spills that have occurred at the site.
The NRC staff reviewed those documents. The WEC and its contractor walked staff through how they would implement the procedure.
The NRC staff reviewed the 70.25(g) files important for decommissioning.
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Provide a knowledgeable person to discuss waste management. The ER included updated information about waste generation rates and management. The rates are much higher than those presented in the NRCs June 2018 EA.
The ER was revised to indicate that mixed waste is generated at CFFF. How much mixed waste is generated? What are the applicable state regulations for the management of mixed waste?
The amount of hazardous waste generated, as presented in Table 2.1-5, almost doubled. What caused the increase in hazardous waste generation? Is the new rate expected to continue through the 40-year license renewal period? What is the generation rate based on - 2017 rates, an average rate?
The 2017 generation rate for solid (A) nonhazardous waste, as presented in Table 2.1-5, increased significantly from the 2013 rate. What caused the increase and is the new rate expected to continue through the 40-year license renewal period?
Table 2.2-1 was updated to indicate that the amount of CaF2 was per shipment. How much CaF2 is shipped offsite per year?
The CaF2 is removed from the lagoons and ultimately shipped offsite for reuse. What procedures does WEC have in place to ensure the CaF2 material is within releasable limits and the material is controlled such that there is no potential to affect the environment? How long is the CaF2 stored before being shipped offsite? What happens to the CaF2 that does not meet the NRC releasable limit?
During an evaluation of its waste streams, WEC identified a new mixed waste stream. They currently have approximately generated 20 drums of low-level mixed waste. The waste stream includes batteries and PCB (polychlorinated biphenyl) ballasts.
The estimated generation rate is expected to be 5-10 drums per year.
Hazardous waste increased due to plating room waste. These rates are expected to have leveled out. The rates provided in Table 2.1-5 are based on 2017 rates.
The WEC stated that bankruptcy and changing recycling markets accounted for the additional generation rates for nonhazardous solid waste (batteries, computers, oil filters and rags).
The CaF2 is shipped off-site approximately every two years as part of the west lagoon dewatering campaigns. In 2014, 3,557 tons were shipped. In 2016, it was 4,578 tons. 3,025 and 5,448 tons were shipped in 2018. Thus the average for 2014-2018 is 4,152 tons. WEC entered a corrective action into its CAP (2019-5894) to address lack of procedures for calcium fluoride campaigns. Procedure will address sampling criteria, permitting (mobile presses) and what to do if samples exceed the free releasable limit. Runoff from the CaF2 storage pad goes through a French drain system back into the West II lagoon.
The CaF2 is stored on-site for two years after dredging and before shipment. If samples exceed 30 pCi/g, then the CaF2 must be shipped offsite as low level radioactive waste or WEC must request an exemption from the NRC.
There have been no planned projects or process improvements to decrease uranium in liquid discharges.
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13 Table 2.1-3 was updated to reflect uranium released in the liquid effluent to include data through 2018.
There is a significant decrease in total uranium discharged in the liquid effluents after 2012. What is the source of the reported decrease (i.e., less liquid volume, better treatment, etc.)?
Confirm that the values in Table 2.2-2-Summary of Environmental Impacts (transportation) and Table B-2-Transportation of Radioactive Materials and Chemicals in Appendix B are still valid based on new waste generation rates and plans to use new Traveler containers.
WEC confirmed that the values in Table 2.2-2 are valid.
5 Provide a knowledgeable person to clarify if any changes have been made to WECs leak detection systems, equipment, and procedures in place to monitor systems or activities, including the waste water treatment lagoons because of recent updates to environmental monitoring program.
The WEC reiterated that they rely on groundwater monitoring for leak detection for underground buried piping (e.g., contaminated wastewater lines) and the wastewater treatment plant (WWTP) lagoons.
There is a functioning French drain system at the West lagoon, used to capture CaF2 material and take it back to the lagoon.
The draft NPDES permit has lagoon inspection requirements and annual reporting requirements to SCDHEC. The NPDES permit was still in draft form at this time. On September 12, 2019, the draft NPDES permit was published for public review and comment.
The lagoons are separated into multiple operating units or OUs, with associated sentinel groundwater wells. The NRC questioned the ability of the groundwater wells near the lagoons to pick up new leaks since many of those wells already pick up historical contamination.
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Provide a knowledgeable person who can discuss the environmental monitoring data provided in the March 2019 RAI response (Enclosure 2).
For several constituents the entry is not analyzed, but should have been, not speciated, but should have been, or not sampled-tubing backordered
[analyses not in the NRC program]. The table contains a footnote CAP 2018 -14353 was written for analysis that was not performed, e.g., Not analyzed, but should have been or Not speciated, but should have been. Provide clarification on the data entries.
For groundwater wells W-7 and W-32, there were numerous gross beta results that were greater than the investigation level of 50 pCi/L, which would have triggered further analysis as required by the current NRC license. However, the Tc-99 result column states, Not analyzed, but should have been. This was the case for all 2007-2009 results, and a few instances in 2013, 2016, and 2017. For W-13, gross alpha results exceeded the 15 pCi/L investigation level in 2011, but no isotopic analysis was performed. Provide clarification.
The WEC is required in its current NRC license to measure gross beta in its fish and sediment samples. There are no gross beta results for fish until Nov 2016 and no sediment beta results until Nov 2012. Provide the missing data or explain why there is no data.
For vegetation, there are no gross beta results until 2016. Provide the missing data or explain why there is no data.
The WEC Congaree River samples from six locations starting in 2010 going until 2016. Why did WEC collect those additional samples and why In those cases where entry reads not analyzed but should have been or not speciated, but should have been, WEC did not conduct the isotopic analysis as required by its NRC license. The NRC reviewed CAP-20188-14353 which identified several issues with environmental data and states that the data collection/trending needs a comprehensive review. No specific actions have been taken at this time but the CAP entry is still open.
The WEC provided an updated version of the environmental sampling results data that was provided in the March 2019 submittal for NRC staff review. The WEC submitted the new version of environmental data, along with the updated LRA Chapter 10 on August 22, 2019.
The WEC made the decision to take supplemental Congaree River samples in 2010 to have additional data points. However, in 2016, after several years with no detections, WEC decided to stop the additional sampling.
The WEC entered an item into their CAP regarding data quality control issues. The WEC is also working with their contracted laboratory about data management and quality control measures.
The soil sample results from the CWW line investigation and 2018 spiking station leak are available for NRC review. The WEC stated they have initiated an effort to collect surface soil samples from around the site as part of an effort to re-baseline.
The WEC provided copies of the 2017 ALARA Report and 1Q 2018 ALARA Report for NRC review.
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13 does WEC feel it is no longer necessary to sample those additional locations?
What quality assurance/quality control procedures does WEC have in place that would prevent an element of sampling not being performed based on an analysis of the prior sampling program?
Provide soil sample results from the 2018 HF spiking station spill and the investigation into the 2011 contaminated wastewater pipe leak.
Provide copies of ALARA reports from 2017 and 2018 for staff review.
7 Provide a knowledgeable person to discuss groundwater conclusions presented in the ER.
The WEC bases its conclusion that there are no immediate off-site impacts, in part, on the fact that the lack of contaminant detections in downgradient wells W-20 and W-25 coupled with years of surface water data collected for the site demonstrate that there is no immediate off-site environmental impact. However, gross alpha and gross beta were detected in W-20 and no data was provided for W-25. What is the basis for the conclusion that there is a lack of contaminant detections in W-20 and W-25?
Besides being downgradient and within the floodplain, clarify that the wells are properly located (vertically and horizontally) to detect any plume given existing knowledge of water table contours and groundwater flow direction from the plant.
In the ER, WEC based its conclusion about groundwater contamination, in part, on the fact that no contamination was found in W-20 or W-25. The WEC clarified that W-25 had been damaged by a fallen tree and was just recently repaired. The only data from W-25 was taken in January 2019. Well W-25 is not currently in the sampling program in the LRA Ch 10 but will be added.
The Remedial Investigation (RI) Workplan for the Consent Agreement, indicates that WEC will be installing two additional groundwater monitoring wells to the east of well W-20 (W-94 and W-95). Two lithographic borings will also be taken. Its possible that in later phases of the RI, more wells/boring could be made south of well W-20.
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Provide an expert who can discuss surface water at the site.
In the updated ER and LRA, WEC included figures showing a surface water ditch that runs from the Lower Sunset Lake east to the site boundary, travels south along the site boundary, and then runs west, back into the confluence of the Man-Made Canal (between Mill Creek segments) and Lower Sunset Lake. Be prepared to discuss this ditch, including any samples that may have been collected and the possibility of groundwater to surface water connectivity.
Provide justification for why the proposed environmental monitoring program would be adequate for the next 40 years without any sampling of this ditch and/or portion of Mill Creek.
Are there any users of Mill Creek between the site boundary and the River and if so, how do they use the water (e.g., drinking, recreation, fishing)?
The AECOM contractors discovered this ditch using Google EARTH but have not walked down the ditch. The ditch is believed to be an old irrigation channel. The CSM incorporates 2018 Richland County geologic data, which supports the general outline of the ditch, however, NRC was not able to see the ditch -
either in person (due to road blocked from fallen tree) nor in the CSM (that portion of the model was not included in version provided for demonstration). The ditch is not included in Phase I of the RI.
It is not known at this time if groundwater intersects with the ditch (depths to groundwater, depths of ditches are not known). Based on current data (google EARTH, Richland County data) WEC believes the ditch re-enters Upper Sunset Lake just above the current exit surface water sampling location. Therefore, WEC believes that the current surface water sampling point is adequate.
The WEC stated they are not aware of users of Mill Creek between the site boundary and the River.
Due to uncertainty about this new ditch, WEC and NRC discussed adding a surface water and sediment sample at the intersection of Lower Sunset Lake and the new ditch as it leaves the lake.
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Provide a knowledgeable person to discuss offsite groundwater wells. In previous RAI responses, WEC indicated that the nearest off-site receptor was a landowner approximately 6,500 feet west of the plume (Response to RAI 74 in ML18087A411). During the NRCs review, WEC indicated that a hunting lodge had a private well but WEC did not believe it was used for drinking water (ML17356A211).
Provide a figure indicating the location of the nearby residents/groundwater wells to the site boundary, including the hunting lodge. Include any information about whether they use groundwater wells for drinking water (or other uses such as irrigation or livestock).
The WEC stated they have no data on the groundwater wells at the hunting lodges located offsite. There are no permanent residences. The SCDHEC stated they had attempted to reach the hunting lodge owners to sample the groundwater well but have not been able to at this time. The WEC does not have any data on the location, use, or description of the well(s).
10 Provide a knowledgeable to discuss the groundwater monitoring well system. At the time of the publication of the EA and FONSI in June 2018, WEC had a groundwater monitoring network of 38 wells, 35 in the water table aquifer and 3 in the deep aquifer. Since then, WEC has installed new wells W-60 through W-68 with plans to install more.
Current groundwater wells are located in the upper and lower surficial aquifer, Black Mingo aquifer, and the Congaree River floodplain. The WEC updated it groundwater monitoring network in the LRA to include sampling the original 38 wells for uranium and Tc-99.
The WEC also updated the well sampling to monitor for uranium and Tc-99, versus gross alpha and gross beta. What is the basis for that decision?
What, if any, relationship is there between gross alpha and uranium detected in the groundwater?
Provide copies of WECs maintenance procedures for ground water wells for NRC review.
In the LRA application/monitoring well program, WEC included the original 38 wells, which are the same wells included in the NPDES permit (related to lagoons).
The WEC is proposing to analyze environmental samples for uranium and Tc-99 versus alpha and beta indicator parameters.
The WEC believes this analysis provides a better characterization of potential radionuclide impacts that could originate from the CFFF. Uranium is the alpha emitter from site, and Tc-99 is the beta emitter. The WEC does not have any correlation analysis for gross alpha and uranium.
The WEC is working on the groundwater well maintenance procedure. The NPDES permit has some well maintenance requirements but those would only apply to the NPDES wells (p 26 of draft NPDES permit).
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13 11 Provide a knowledgeable person to discuss the Tc-99 groundwater contamination.
The sampling data provided in the RAI response indicates that in recent sampling campaigns (Oct 2018) Tc-99 exceeded the EPAs drinking water standard (MCL) of 900 pCi/L in W-11. The WEC previously determined that the elevated levels of gross beta were due to Tc-99 most likely from hydrostatic testing process. In the ER update, WEC stated that the Remedial Investigation (RI) workplan describes the continued investigation into the Tc-99 sources. Provide the RI workplan for staff review and be prepared to discuss those investigations.
The WEC does not know what the source of the Tc-99 contamination is and thus further investigation is warranted.
Section 3.5.7 of the Remedial Investigation Work Plan describes some potential sources and the investigations planned to determine the source and extent of Tc-99 contamination.
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13 12 Provide an expert who can explain and demonstrate the Conceptual Site Model (CSM). In the updated ER and LRA, WEC indicates that monitoring data has been entered into a newly created CSM. The WEC also states that the CSM incorporates what is known about the sites hydrogeology, the fate and transport of past releases.
In the LRA, WEC states that the CSM will be updated on a periodic frequency. What is that frequency and the basis for that frequency?
What administrative controls, procedures or plans does WEC have in place to manage and maintain the CSM?
The contractor for WEC, AECOM, demonstrated how information is populated in the CSM and how the CSM shows where the subsurface contamination exists. Currently, AECOM maintains the tool, updating it when new sampling data is available.
The WEC developed two new procedures, RA-434 Environmental Data Management and RA-435Conceptual Site Model Development. Procedure RA-434 outlines how WEC will assess and detect potential trends from the environmental monitoring data and how the data is managed and controlled, including receipt of incoming data and CSM outputs. Procedure RA-435 describes how the CSM is developed and updated. The procedure states only that the CSM will be updated, but no specific frequency is given.
The CSM is still being developed and will be updated as new information is learned from sampling and investigation activities.
The WEC and AECOM stated they are aware that the site/floodplains are not homogenous and therefore the additional sampling and investigations will help provide more information on the site-specific heterogeneities.
The CSM does not determine the fate and transport. The CSM does include the data from the 2008 and 2011 leaks from the CWW. The depths of the lagoons are included in the CSM.
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13 13 Provide an expert who can explain how WEC relies upon operable units. In the updated LRA (Chapter 10) and ER, WEC introduces operable units.
Define each operable unit and indicate which groundwater monitoring wells or other sampling points are associated with each operable unit.
Explain how the characteristics of each OU, combined with the CSM, will inform the sampling and monitoring program and how that will be documented.
Provide figures that show each operable unit and what features are included (e.g, UF6 cylinder washing area, lagoons, tanks).
The RI Work Plan includes figures of the site divided into operable units (OUs). They are not defined in Ch 10 of the LRA nor in the procedures, but it is a concept from the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA). The OUs help refine the specific area and issue when determining the remedial actions to be taken.
The WEC and its contractor, AECOM, demonstrated how the CSM can be isolated for each OU. The OUs were developed based on the activities and contaminants of concern in a certain area. The WEC stated that the OUs can change, be added, be deleted, as the site investigations and possible remediation progress.
The WEC has created four bins of groundwater wells - plume wells, sentinel/OU wells, NPDES permit wells, and perimeter wells. Each OU has groundwater wells within them that WEC states will serve as an indicator of contamination leaving that OU.
14 Provide a knowledgeable person to discuss the status of permits and agreements with S.C. Department of Health and Environmental Control (SCDHEC).
Consent Agreement Air Quality Permit renewal NPDES Permit renewal The Consent Agreement was executed in February 2019. On June 19, 2019, SCDHEC approved the RI Work Plan so WEC can begin the activities referenced in the Work Plan. The WEC began installing wells in June 2019. The SCDHEC office that manages the Consent Agreement is the Bureau of Waste which is a different group than the NPDES permitting (water bureau).
The WEC submitted a timely NPDES permit renewal application and SCDHEC is currently reviewing it. The WEC explained their current understanding and timeframes for SCDHECs review for the air quality and NPDES permits. The draft NPDES permit includes monitoring of groundwater wells associated with the lagoons. The WEC and SCDHEC will have to work through the reporting requirements for NPDES and Consent Agreement and when/how the results are reported. The WEC stated that anytime 13
13 a sample is collected, even if not required, they must report the results within the NPDES permit.
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