Exelon Generation Co., LLC; Dresden Nuclear Power Station, Units 2 and 3

SUMMARY

The U.S. Nuclear Regulatory Commission (NRC) is considering a request by Exelon Generation Company, LLC (Exelon, the licensee) dated March 18, 2014, as supplemented by letters dated May 20 and June 8, 2015, for onsite disposal of slightly contaminated soil at the Dresden Nuclear Power Station (DNPS), Units 2 and 3.

 
CONTENT

Federal Register, Volume 80 Issue 192 (Monday, October 5, 2015)

Federal Register Volume 80, Number 192 (Monday, October 5, 2015)

Notices

Pages 60183-60189

From the Federal Register Online via the Government Publishing Office www.gpo.gov

FR Doc No: 2015-25292

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NUCLEAR REGULATORY COMMISSION

Docket Nos. 50-237 and 50-249; NRC-2015-0232

Exelon Generation Co., LLC; Dresden Nuclear Power Station, Units 2 and 3

AGENCY: Nuclear Regulatory Commission.

ACTION: Environmental assessment and finding of no significant impact; issuance.

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SUMMARY: The U.S. Nuclear Regulatory Commission (NRC) is considering a request by Exelon Generation Company, LLC (Exelon, the licensee) dated March 18, 2014, as supplemented by letters dated May 20 and June 8, 2015, for onsite disposal of slightly contaminated soil at the Dresden Nuclear Power Station (DNPS), Units 2 and 3.

DATES: October 5, 2015.

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ADDRESSES: Please refer to Docket ID NRC-2015-0232 when contacting the NRC about the availability of information regarding this document. You may obtain publicly-available information related to this document using any of the following methods:

Federal Rulemaking Web site: Go to http://www.regulations.gov and search for Docket ID NRC-2015-0232. Address questions about NRC dockets to Carol Gallagher; telephone: 301-415-

3463; email: Carol.Gallagher@nrc.gov. For technical questions, contact the individual listed in the FOR FURTHER INFORMATION CONTACT section of this document.

NRC's Agencywide Documents Access and Management System (ADAMS): You may obtain publicly-available documents online in the ADAMS Public Documents collection at http://www.nrc.gov/reading-rm/adams.html. To begin the search, select ``ADAMS Public Documents'' and then select ``Begin Web-based ADAMS Search.'' For problems with ADAMS, please contact the NRC's Public Document Room (PDR) reference staff at 1-800-397-4209, 301-415-4737, or by email to pdr.resource@nrc.gov. The ADAMS accession number for each document referenced (if it available in ADAMS) is provided the first time that a document is referenced.

NRC's PDR: You may examine and purchase copies of public documents at the NRC's PDR, Room O1-F21, One White Flint North, 11555 Rockville Pike, Rockville, Maryland 20852.

FOR FURTHER INFORMATION CONTACT: Russell Haskell, Office of Nuclear Reactor Regulation, U.S. Nuclear Regulatory Commission, Washington, DC 20555-0001; telephone: 301-415-1129, email: Russell.Haskell@nrc.gov.

SUPPLEMENTARY INFORMATION:

  1. Introduction

    The NRC is considering approval of a request dated March 18, 2014 (ADAMS Accession No. ML14077A140), as supplemented by letters dated May 20 (ADAMS Accession No. ML15140A728) and June 8, 2015 (ADAMS Accession No. ML15163A304), from Exelon Generation Company, LLC (Exelon, the licensee) for onsite disposal of slightly contaminated soil at the Dresden Nuclear Power Station (DNPS), Units 2 and 3, located in Grundy County, Illinois. The site consists of three units. Units 2 and 3 are operating nuclear reactors and Unit 1 was shut-down in 1978 and is currently in SAFSTOR \1\. Units 2 and 3 are boiling-water reactors (BWRs) and the cooling system includes cooling towers, cooling canals, and a cooling pond. The licensee is requesting approval in accordance with section 20.2002 of Title 10 of the Code of Federal Regulations (10 CFR), ``Method for obtaining approval of proposed disposal procedures,'' to land-spread a current accumulated inventory of approximately 6,000 cubic meters (m\3\) (211,888 cubic feet ft\3\) of soil. Additionally, the licensee has requested the NRC's approval to conduct future disposal operations onsite, not to exceed a total disposed volume of 20,000 m\3\ (706,293 ft\3\) of soil and sludge containing trace quantities of residual radioactive material in a designated area on the DNPS site. Based on the results of the Environmental Assessment (EA) that follows, the NRC has determined not to prepare an Environmental Impact Statement for the proposed action, and is issuing a Finding of No Significant Impact.

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    \1\ SAFSTOR is a decommissioning strategy under which a nuclear facility is placed in a safe, stable condition and maintained in that state (safe storage) until it is subsequently decontaminated and dismantled to levels that permit license termination.

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    Under 10 CFR 20.2002, a licensee may seek NRC authorization to dispose of licensed material using procedures not otherwise authorized by the NRC's regulations. A licensee's supporting analysis must show that the radiological doses arising from the proposed disposal will be within the 10 CFR part 20, ``Standards for Protection Against Radiation,'' dose limits and will be as low as is reasonably achievable.

  2. Environmental Assessment

    Description of Proposed Action

    The proposed action would permit the disposal of up to 20,000 m\3\ (706,293 ft\3\) of soil and sludge containing trace quantities of residual radioactive material in a 100 m (328 ft.) by 100 m (328 ft.) plot located on the owner-controlled area on the north side of the DNPS site.

    The DNPS has accumulated a current inventory of approximately 6,000 m\3\ (211,888 ft\3\) of soil containing trace quantities of radionuclides as part of multiple pipe repair and replacement projects conducted onsite over the past several years. The soil is currently located within the DNPS site's protected area portion of the restricted area and is contained within a concrete berm. Tarps and spray-on sealants are employed to limit erosion and migration of the soil (Exelon 2015a). The submittal requests approval for disposal of the initial 6,000 m\3\ (211,888 ft\3\) of soil and a total disposal of up to 20,000 m\3\ (706,293 ft\3\) of soil and sludge that may be generated from future projects. Contaminated soil generated as a result of future projects at DNPS (up to a total of 20,000 m\3\ (706,293 ft\3\)) will be temporarily stored in the protected area until analyses for release is completed and will then be transferred and emplaced to the proposed disposal area. The soils will be transferred to the proposed disposal area in campaigns (6,000 m\3\ (211,888 ft\3\) of soil or less per campaign). The first campaign will include site preparation activities (land clearing, excavation, and grading) of the 100 m (328 ft.) by 100 m (328 ft.) proposed disposal area and immediate transfer and emplacement of the current 6,000 m\3\ (211,888 ft\3\) of soil to the disposal area. Transportation of the soil (via dump trucks) from its current location to the proposed disposal area will be maintained within the boundaries of the DNPS property at all times. Once transferred and emplaced, Exelon will grade and over-seed the soil with native grass (Exelon 2015a). Exelon plans to maintain the proposed disposal area in accordance with the Illinois Urban Manual for Erosion and Sediment Control Best Management Practices (AISWCD 2013).

    The proposed action is in accordance with the licensee's application dated March 18, 2014 (ADAMS Accession No. ML14077A140), as supplemented by letters dated May 20, 2015 (ADAMS Accession No. ML15140A728), and June 8, 2015 (ADAMS Accession No. ML15163A304).

    Need for the Proposed Action

    The proposed action is requesting the NRC's approval for the onsite disposal of a current inventory of 6000 m\3\ (211,888 ft\3\) of soil. The request also includes an NRC's approval for an upper disposal limit not to exceed 20,000 m\3\ (706,293 ft\3\) of soil and sludge to account for future onsite excavation projects requiring disposal.

    Benefits to the licensee's proposed action include significantly reduced transportation distances and costs incurred as a result of offsite disposal, while maintaining protection of public health and safety and the environment. This request provides the licensee with an alternative to the usage of offsite shallow land burial waste repositories consistent with a previously released NRC Information Notice 83-05, ``Obtaining Approval for Disposal of Very Low-Level Radioactive Waste.''

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    Environmental Impacts of the Proposed Action

    Radiological Impacts and Human Health

    Occupational Dose

    The proposed DNPS request for onsite disposal of slightly contaminated soil will not require any physical changes to the plant or plant operations; therefore, there will be no change to any in-plant radiation sources. Approximately 6,000 m\3\ (211,888 ft\3\) of soil is currently located within the DNPS site's protected area portion of the restricted area. The soil is contained within a concrete berm area; tarps and spray-on sealants are employed to limit erosion and migration of the soil (Exelon 2015a).

    The DNPS radiation protection program establishes appropriate work controls, training, temporary shielding, and protective equipment requirements so that worker doses will remain within the dose limits of 10 CFR part 20. The main pathway of concern for worker exposure to radiation would be from fugitive dust emissions during the transport and emplacement of the slightly contaminated soil to the proposed onsite disposal area. To minimize those fugitive dust emissions, Exelon will use best management practices (BMPs) such as using equipment with enclosures during the transport of the soil and dampening the soil. Once the soil is transferred and emplaced to the proposed disposal area, Exelon will over-seed the soil with native grass and monitor to minimize fugitive dust emissions. To limit access to the proposed disposal area, DNPS plans to implement institutional controls such as sign postings and DNPS Security monitoring (Exelon 2015a).

    Slightly contaminated soil generated as a result of future projects at DNPS (up to a total of 20,000 m\3\ (706,293 ft\3\) will be temporarily stored in the protected area until an analysis is completed documenting that the material meets radiological criteria for disposal per 10 CFR 20.2002 and will then be transferred to the proposed disposal area.

    The proposed DNPS onsite disposal of slightly contaminated soil will not affect radiation levels within the plant restricted area and will be performed in accordance with the proper oversight of their radiation protection program, and therefore will have no significant radiological impact to the workers.

    Offsite Dose

    The primary sources of offsite dose to members of the public from the DNPS are radioactive gaseous and liquid effluents. As discussed above, the request for onsite disposal of slightly contaminated soil will be on the DNPS site. As such, members of the public will not have access to the disposal area. Therefore, there is no direct radiation exposure to the public. In addition, the proposed action does not require any physical changes to the plant or plant operations; therefore, there will be no change to the types and quantities of radioactive effluents and the operation of the radioactive gaseous and liquid waste management systems to perform their intended functions. As stated above, the soil will be over-seeded with native grass and monitored to minimize fugitive dust emissions once the soil is transferred to the proposed disposal area. To manage any soil runoff, Exelon will use the BMPs outlined in the Illinois Urban Manual for Erosion and Sediment Control Best Management Practices. The licensee plans to install three surficial groundwater monitoring wells, one up-

    gradient and two down-gradient of the proposed disposal area. These new wells will be added to the DNPS Radiological Ground Protection Program (RGPP) to monitor for any migration of contamination (Exelon 2015a). Based on the above, the offsite radiation dose to members of the public would not change and would continue to be within regulatory limits and therefore would not be significant.

    Radiological Impacts Summary

    Based on the radiological evaluations discussed above, the NRC staff has determined the proposed action would not result in significant radiological impacts.

    Land Use

    Current land uses would be unaffected by the proposed onsite disposal of the contaminated soil at the DNPS. The proposed disposal area is currently part of an industrial power plant site and would remain so if the proposed action is approved. Therefore, the NRC staff has determined that there would be no significant land use impacts associated with the proposed action.

    Water Resources

    The disposal location is an elevated plot of land that has been heavily disturbed by previous soil stockpiling and grading activities and which generally slopes to the west. Site preparation activities, transfer, and emplacement of slightly contaminated soil under the proposed action would have no direct impact on natural surface-water drainages as none exist on or immediately adjacent to the disposal area. The closest surface-water feature to the center point of the disposal area is a shallow drainage depression adjacent to the south bank of the Illinois River and located approximately 600 ft. (183 m) to the northwest. The Units 2 and 3 discharge canal to the Illinois River lies approximately 700 to 800 ft. (213 to 244 m) to the south and east of the disposal area.

    Precipitation and associated storm-water runoff from the disposal area have the potential to erode soils and transport suspended sediments away from the site and toward nearby surface water features. This is most likely to occur during the course of each disposal campaign, as the surface of disposal area is reworked and graded with each disposal operation. However, disposal site operations would be subject to the DNPS Storm Water Pollution Prevention Plan (SWPPP), which the licensee is required to implement and maintain in accordance with Special Condition 10 of DNPS's National Pollutant Discharge Elimination System (NPDES) permit (No. IL0002224). The SWPPP prescribes BMPs for soil erosion and sediment control, storm-water pollution prevention, waste management, and spill response. During operations, the licensee will use BMPs as prescribed in the SWPPP in combination with those outlined in the Illinois Urban Manual for Erosion and Sediment Control Best Management Practices. For instance, soils would be graded and seeded with native grasses to minimize surface drainage and runoff and associated erosion of the site (Exelon 2015a). Adherence to these measures would prevent or minimize any surface water quality or groundwater quality impacts during disposal operations.

    Over the longer term, management and monitoring activities would ensure that there are no inadvertent offsite impacts to surface water or groundwater quality as a result of disposal site operations. The licensee proposes to install three surficial groundwater monitoring wells in order to characterize baseline groundwater quality as well as any changes over time. The wells will be installed at depths of 15 to 35 feet (4.5 to 10.6 m) below ground surface. Two wells will be installed up-gradient of the disposal area relative to groundwater flow, and one will be installed down-gradient. Upon installation, baseline groundwater sampling and analysis would be performed including for gamma, tritium, gross alpha, gross beta, strontium-89, and strontium-90. The completed wells would be included in the DNPS RGPP with routine monitoring for radiological constituents and other parameters as prescribed by RGPP protocols (Exelon

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    2015a). Based on the above information, the NRC staff has determined the impacts to water resources would not be significant.

    Air Resources

    With regards to the National Ambient Air Quality Standards (NAAQS) criteria for pollutants (ozone, carbon monoxide, lead, particulate matter, nitrogen oxides, and sulfur dioxide), Grundy County is designated as a non-attainment area for the 8-hr ozone (2008) standard and 1-hr ozone (1979) standard and a maintenance area for particulate matter less than 2.5 microns (1997) standard and 8-hr ozone (1997) standard (40 CFR 81.314). Air emissions would be predominantly from the transfer of the soil to the proposed site, equipment used in transporting the soil (dump trucks and front end loaders), and site preparation related activities (land clearing, excavation, and grading). The loading and off-loading of the soil and excavation of the proposed site can result in fugitive dust emissions; fugitive dust is particulate matter suspended in the air. Equipment exhaust emits criteria pollutants.

    Site preparation activities of the 100 m (328 ft.) by 100 m (328 ft.) proposed disposal area and transfer and emplacement of the 6,000 m\3\ (211,888 ft\3\) of soil are estimated to be completed within two weeks (Exelon 2015a). Air emission estimates as a result of site preparation activities and transfer and disposal the 6,000 m\3\ (211,888 ft\3\) of soil are presented in Table 1. To minimize fugitive dust emissions, Exelon will use best management practices to include using equipment with enclosures during the transport of the soil and watering the soil (Exelon 2015a). Once the soil is transferred to the proposed disposal area, Exelon will over-seed the soil with native grass and monitor to minimize fugitive dust emissions.

    Table 1--Air Emissions From Site Preparation Activities and Soil Disposal

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    Emissions (tons/yr)

    Source ------------------------------------------------------

    CO NOX SO2 PM10 PM2.5 VOC

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    Equipment Exhaust (a).................................... 0.28 1.32 0.08 0.09