ML20266G552
| ML20266G552 | |
| Person / Time | |
|---|---|
| Site: | Westinghouse |
| Issue date: | 09/22/2020 |
| From: | Westinghouse |
| To: | Office of Nuclear Material Safety and Safeguards |
| Shared Package | |
| ML20266G550 | List: |
| References | |
| LTR-RAC-20-74 | |
| Download: ML20266G552 (12) | |
Text
Attachment 1 to LTR-RAC-20-74 Date: September 22, 2020 Attachment 1 Response to Request for Additional Information Request for Alternate Disposal Approval and Exemption for Specific Columbia Fuel Fabrication Facility Waste 1 of 12 to LTR-RAC-20-74 Date: September 22, 2020
- 1. Please confirm the volumes of material being removed from the East Lagoon for disposal.
There appears to be a discrepancy with regards to the volumes of material being disposed from the East Lagoon. According to Table 4.2 of Enclosure 1 and the inputs to the Site Specific Dose Assessment for US Ecology Idaho, Inc. (USEI) (SSDA) spreadsheet, the volume of East Lagoon material being disposed is 44,776 (45,000) ft3 of soil, sludge, and debris with the potential for another 45,000 ft3 of soil from below the liner. However, the submittal describes the East Lagoon as being approximately 160 ft x 130 ft and contains approximately 3 to 4 ft of contaminated sludge. This would result in a volume of soil, sludge, and debris that ranges between 62,400 ft3 and 83,200 ft3 of potential waste above the liner (and a total volume of 124,800 ft3 to 166,400 ft3 when considering the equivalent volume of soil from below the liner).
Regulatory Basis: This information is needed to ensure accurate parameter values are considered when assessing doses associated with this proposed disposal action in accordance with 10 CFR 20.2002 and, more specifically, that an accurate description of the waste is considered in accordance with 10 CFR 20.2002(a).
WESTINGHOUSE RESPONSE:
Westinghouse confirms that the volume of soil, sludge and debris from the East Lagoon has been estimated to be 44,776 (rounded to 45,000) ft3. While the overall area of the East Lagoon is 160 ft x 130 ft and contains 3 to 4 ft of contaminated sludge, the actual area of the lagoon that is covered by water is about 138 ft x 111 ft, and the depth of sludge varies across the East Lagoon.
To estimate the actual volume of East Lagoon material for disposal, a detailed depth analysis utilizing a survey pole and auto level in a grid system was performed. The photograph below presents the column and row grid system utilized to perform the depth analysis.
2 of 12 to LTR-RAC-20-74 Date: September 22, 2020 The below table presents the results of the depth analysis performed to determine the East Lagoon disposal volume.
C1 C2 C3 C4 C5 C6 Totals Sludge Layer inches 20.00 34.00 33.00 30.00 36.00 33.00 ROW 1 Sludge Layer Feet 1.67 2.83 2.75 2.50 3.00 2.75 Survey Cell SqFt 632.50 632.50 632.50 632.50 632.50 632.50 Sludge Cubic Feet 948.75 1612.88 1565.44 1423.13 1707.75 1565.44 8823.38 Sludge Layer inches 32.00 32.00 40.00 38.00 37.00 39.00 ROW 2 Sludge Layer Feet 2.67 2.67 3.33 3.17 3.08 3.25 Survey Cell SqFt 632.50 632.50 632.50 632.50 632.50 632.50 Sludge Cubic Feet 1518.00 1686.67 2108.33 2002.92 1950.21 1850.06 11116.19 Sludge Layer inches 43.00 48.00 46.00 44.00 38.00 42.00 ROW 3 Sludge Layer Feet 3.58 4.00 3.83 3.67 3.17 3.50 Survey Cell SqFt 632.50 632.50 632.50 632.50 632.50 632.50 Sludge Cubic Feet 2039.81 2530.00 2424.58 2319.17 2002.92 1992.38 13308.85 Sludge Layer inches 21.00 45.00 44.00 39.00 50.00 44.00 ROW 4 Sludge Layer Feet 1.75 3.75 3.67 3.25 4.17 3.67 Survey Cell SqFt 632.50 632.50 632.50 632.50 632.50 632.50 Sludge Cubic Feet 996.19 2134.69 2087.25 1850.06 2371.88 2087.25 11527.31 Estimated Sludge Volume 44775.73 Cubic Feet The standing water in the East Lagoon will be pumped out prior to beginning remediation operations as per normal wastewater treatment operations. This water will be treated in accordance with the Columbia Fuel Fabrication Facility (CFFF) National Pollutant Discharge Elimination System (NPDES) permit, and will not be included in the disposal volume sent to US Ecology Idaho (USEI).
3 of 12 to LTR-RAC-20-74 Date: September 22, 2020
- 2. Please clarify what actions are being performed on the East Lagoon liner and how the impacts from these actions are considered in the SSDA dose calculations.
Processes discussed in the submittal include the removal of the liner in order to evaluate and remove the underlying soil. There are no additional details regarding future actions regarding the liner once it has been removed (i.e., is it staying on site? is it being included in the material shipped to USEI?) beyond noting that the material being removed from the East Lagoon includes soil, sludge, and debris. Enclosure 4 of the submittal, which provides screenshots of the SSDA input pages, identifies the material being considered in the dose calculations to be Soil and not Mix of Soil/Debris and no analytical data or processes for assessing the potential for radioactive material being associated with the liner are included in the submittal.
Regulatory Basis: This information is needed to ensure accurate parameter values are considered when assessing doses associated with this proposed disposal action in accordance with 10 CFR 20.2002 and, more specifically, that an accurate description of the waste is considered in accordance with 10 CFR 20.2002(a).
WESTINGHOUSE RESPONSE:
During and following removal of the sludge from the East Lagoon Westinghouse intends to wash down the liner while in place with high pressure, low volume power washers. Once the liner is as clean a practical, it will be removed by slicing it and rolling it up for packaging for disposal at USEI.
The volume of the liner is approximately 62.4 ft3 (based on maximum dimensions 160 ft x 130 ft x 0.003 ft) which represents 0.14 % of the 44,776 ft3 East Lagoon waste volume.
Additionally, the liner is made of non-permeable material (Hypalon). As such, it is considered to be surface contaminated and not volumetrically contaminated. Therefore, its radiological characteristics, as with the Additional Soil as described in Section 3.4.1, Additional Soil Radiological Characterization of the submittal1 would be that of the source of the radiological contamination which is the East Lagoon sludge.
The Site Specific Dose Assessment (SSDA) utilizes the following densities based upon the input selected; Soil - 1.2 g/cc, Soil/Debris - 0.82 g/cc and Debris - 0.44 g/cc. For the purpose of the SSDA calculations, the East Lagoon liner volume is insignificant (less than 1% of the East Lagoon total waste volume) and as such does not impact the overall density of the East Lagoon waste stream. Therefore, Westinghouse and USEI considered the use of Soil density rather than the density of Mix of Soil/Debris as the appropriate representative description of the East Lagoon waste.
1 Westinghouse (A.J. Spalding) to NRC (Document Control Desk) dated May 8, 2020, Request for Alternate Disposal Approval and Exemption for Specific Columbia Fuel Fabrication Waste (ML20129J934) 4 of 12 to LTR-RAC-20-74 Date: September 22, 2020
- 3. Please clarify how doses to the CFFF workers responsible for preparing the material for shipment to USEI are evaluated or provide justification for why they are not considered in the proposed disposal action (e.g., onsite radiation protection plan). Also, please document how doses to USEI staff performing bench scale testing of the aggregate waste on site at CFFF were considered.
USEIs SSDA evaluates the doses to individuals associated with the transportation of material to USEI and the disposal of the material at USEI. It does not calculate the doses to USEI workers who may be involved with other activities associated with a proposed disposal request (e.g., collecting, testing, packaging, and loading the material to be shipped to USEI).
Since the purpose of this submittal is to obtain approval to dispose of the material from CFFF at USEI, doses to all USEI workers associated with the disposal process need to be considered.
Regulatory Basis: This information is needed to ensure that the relevant exposure scenarios are considered when assessing doses associated with this proposed disposal action in accordance with 10 CFR 20.2002.
WESTINGHOUSE RESPONSE:
These doses were evaluated in accordance with the CFFF NRC License SNM-1107. Chapter 5.2.42 of the license states: Adults likely to receive greater than 0.5 rem in a year, from sources external to the body, are monitored by personnel dosimeters. This monitoring requirement applies to all occupationally exposed workers at the CFFF, including USEI personnel and other sub-contractors. A prospective ALARA analysis is performed during pre-job activities, and a Radiation Work Permit (RWP) is developed to document the necessary personnel monitoring requirements and Health Physics oversight for performing the work.
The RWP covers all of the radiation safety controls, for the scope of work performed at CFFF, i.e., contamination control, air sampling, protective clothing, and any bioassay sampling requirements as applicable. Personnel working under the RWP are included in the applicable monitoring programs governed by CFFFs NRC license. Only personnel who have completed required safety training and are on the approved personnel list are assigned to work under an RWP.
The SSDA is only intended to evaluate the doses associated with the transportation and disposal of material at the USEI disposal facility. All other potential occupational exposures will be tracked and monitored as part of licensed activities as was the case with the USEI staff that performed the bench scale testing.
5 of 12 to LTR-RAC-20-74 Date: September 22, 2020
- 4. Please confirm the version of the SSDA used to perform the analyses as well as the value for the Waste Contact Time (hr) for the Gondola Railcar Surveyors, 0.16, used to calculate doses to US Ecology workers associated with the disposal of CFFF material at USEI.
While reviewing specific parameter values used to calculate doses to USEI workers disposing of CFFF material, NRC staff noted that the Waste Contact Time (hr) value for the Gondola Railcar Surveyors was 0.16 and not 0.33, the value included in Version 3a of the SSDA, approved May 20, 2019 (ADAMS Accession Number ML19122A340). NRC staff also noted that the SSDA worksheets used to perform these Westinghouse analyses are identified as Version 3 while the worksheets included in the version of the SSDA approved on May 20, 2019, were identified as Version 3a.
Regulatory Basis: This information is needed to ensure both the licensee and NRC staff are using consistent analytical tools and accurate parameter values to assess doses associated with the proposed disposal action in accordance with 10 CFR 20.2002 and, more specifically, that an accurate assessment of the doses to USEI workers and members of the public are calculated in accordance with 10 CFR 20.2002(d).
WESTINGHOUSE RESPONSE:
Version 3a of the SSDA should have been used. The SSDA has been updated utilizing Version 3a and the Waste Contact Time (hr) for the Gondola Surveyor has been corrected to 0.33. Updated Table 5.1 of the submittal is provided below as well as the updated Data Input Worksheets (Enclosure 4 of the submittal).
6 of 12
Attachment 1 to LTR-RAC-20-74 Date: September 22, 2020 Table 5.1 Results of SSDA Dose Evaluation for CFFF Waste Project Total Total % of External External Total Internal Project Max Minimum Waste Exposure Internal Dose per Dose per Dose per Annual Number of Contact Rate Dose Rate Distance Total No. of Worker Worker Worker MEI Function Workers Time (hr) (mrem/hr) (mrem/hr) (m) Repetitions (mrem) (mrem) (mrem) Dose Legacy Waste Streams East Lagoon/CaF2/Soils FrontEnd Dray Truck Drivers 4 0.09 9.99E04 0.00E+00 0.6 355 8.06E03 0.00E+00 8.06E03 0.2%
Gondola Railcar Surveyors 4 0.33 6.91E04 0.00E+00 1.0 71 4.05E03 0.00E+00 4.05E03 0.1%
Bulk/IMC Truck Surveyors (RTF) 4 0.08 7.82E04 0.00E+00 1.0 209 3.27E03 0.00E+00 3.27E03 0.1%
RTF Excavator Operator 2 0.75 5.25E04 2.65E02 2.0 71 1.40E02 7.05E01 7.19E01 14.4%
Gondola Railcar Cleanout 4 0.16 6.63E04 2.65E02 0.3 71 1.88E03 7.52E02 7.71E02 1.5%
BackEnd Dray Truck Drivers 8 0.75 9.99E04 0.00E+00 0.6 209 1.96E02 0.00E+00 1.96E02 0.4%
Landfill Cell Operators 2 0.25 1.95E04 2.65E02 1.0 142 3.45E03 4.70E01 4.74E01 9.5%
Legacy Waste Streams UF6 Cylinders LongHaul Direct Truck Drivers Drive Time 5 45.45 5.64E05 0.00E+00 0.6 20 1.03E02 0.00E+00 1.03E02 0.2%
Bulk/IMC Truck Surveyors (disposal site) 4 0.08 4.58E05 0.00E+00 1.0 20 1.83E05 0.00E+00 1.83E05 0.0%
Landfill Cell Operators 2 0.25 1.30E05 1.03E03 1.0 8 1.30E05 1.03E03 1.04E03 0.0%
Project DoseTotals LongHaul Direct Truck Drivers Drive Time 1.03E02 0.00E+00 1.03E02 0.2%
FrontEnd Dray Truck Drivers 8.06E03 0.00E+00 8.06E03 0.2%
Gondola Railcar Surveyors 4.05E03 0.00E+00 4.05E03 0.1%
Bulk/IMC Truck Surveyors (RTF highest dose reported) 3.27E03 0.00+00 3.27E03 0.1%
RTF Excavator Operator 1.40E02 7.02E01 7.19E01 14.4%
Gondola Railcar Cleanout 1.88E03 7.48E02 7.71E02 1.5%
BackEnd Dray Truck Drivers 1.96E02 0.00E+00 1.96E02 0.4%
Landfill Cell Operators (summed) 3.46E03 4.71E01 4.75E01 9.5%
7 of 12 to LTR-RAC-20-74 Date: September 22, 2020 Updated Version 3a Data Input Worksheets 8 of 12 to LTR-RAC-20-74 Date: September 22, 2020 9 of 12 to LTR-RAC-20-74 Date: September 22, 2020 10 of 12 to LTR-RAC-20-74 Date: September 22, 2020 11 of 12 to LTR-RAC-20-74 Date: September 22, 2020
- 5. Please explain Westinghouses plans for (i) replacing the function the east lagoon served and (ii) the area where the east lagoon is located after its removal.
Regulatory Basis: This information is being requested in accordance with 10 CFR 51.41, to support the NRCs National Environmental Policy Act review.
WESTINGHOUSE RESPONSE:
Westinghouse is in the process of implementing capital improvement projects to re-route inputs to the East Lagoon to other parts of its wastewater treatment system; replace the East Lagoons current function with a storage tank; and formally close the East Lagoon in 2021.
These modifications are being performed in accordance with the NPDES permit
- SC0001848 issued by the South Carolina Department of Health and Environmental Control (DHEC) as well as Richland County requirements. This project also includes assessing the soil underneath the liner in accordance with the Westinghouse-DHEC Consent Agreement and performing any necessary remedial actions based on the assessment data and in consultation with DHEC. Following these activities, Westinghouse plans to backfill the former East Lagoon area with virgin materials and seed the area for erosion control.
12 of 12