L-MT-24-029, Subsequent License Renewal Application Response to Request for Additional Information and Request for Confirmation of Information-Supplement to Set 1 Part 2 and Response to 2ci Round RAI
| ML24281A054 | |
| Person / Time | |
|---|---|
| Site: | Monticello  |
| Issue date: | 09/13/2024 |
| From: | Hafen S Northern States Power Company, Minnesota, Xcel Energy |
| To: | Office of Nuclear Material Safety and Safeguards, Document Control Desk |
| References | |
| L-MT-24-029 | |
| Download: ML24281A054 (1) | |
Text
Withheld From Public Disclosure Under 10 CFR 2.390
Xcel Energy*
2807 West County Road 75 Monticello, MN 55362 September 13, 2024 L-MT-24-029 10 CFR 54.17 ATTN: Document Control Desk U.S. Nuclear Regulatory Commission Washington, DC 20555-0001 Monticello Nuclear Generating Plant Docket No. 50-263 Renewed Facility Operating License No. DPR-22 Subsequent License Renewal Application Response to Request for Additional Information and Request for Confirmation of Information - Supplement to Set 1 Part 2 and Response to 2°ci Round RAI
References:
- 1) Letter from Northern States Power Company, a Minnesota corporation (NSPM), d/b/a Xcel Energy to Document Control Desk, "Monticello Nuclear Generating Plant Docket No. 50-263, Renewal License Number DPR-22 Application for Subsequent Renewal Operating License" dated January 9, 2023, M L23009A353
- 2) Email from the NRC to Northern States Power Company, a Minnesota corporation (NSPM), d/b/a Xcel Energy, "Monticello, Unit 1, Subsequent License Renewal Application Requests for Confirmation of Information Environmental Review" dated October 23, 2023, ML23291A109
- 3) Letter from Northern States Power Company, a Minnesota corporation (NSPM), d/b/a Xcel Energy to Document Control Desk, "Monticello Nuclear Generating Plant, Subsequent License Renewal Application Response to Request for Additional Information and Request for Confirmation of Information - Set 1" dated November 21, 2023, ML23332A182
- 4) Letter from Northern States Power Company, a Minnesota corporation (NSPM), d/b/a Xcel Energy to Document Control Desk, "Monticello Nuclear Generating Plant, Subsequent License Renewal Application Response to Request for Additional Information and Request for Confirmation of Information - Set 1 Part 2" dated December 18, 2023, ML23352A081
Document Control Desk L-MT-24-029 Page 2
- 5) Letter from Northern States Power Company, a Minnesota corporation (NSPM), d/b/a Xcel Energy to Document Control Desk, Monticello Nuclear Generating Plant, Subsequent License Renewal Application Response to Request for Additional Information and Request for Confirmation of Information -
Supplement to Set 1 Part 1 dated February 20, 2024, ML24088A215
- 6) Email from the NRC to Northern States Power Company, a Minnesota corporation (NSPM), d/b/a Xcel Energy, Monticello, SLRA - 2nd Round Request for Additional Information dated August 26, 2024, ML24254A454 Northern States Power Company, a Minnesota corporation, doing business as Xcel Energy (hereafter "NSPM") submitted a response to a request for con"rmation of information (RCI) and request for additional information (RAI) to the Subsequent License Renewal Application, listed in Reference 1.
In an e-mail from the NRC to NSPM, listed in Reference 2, the NRC transmitted Environmental RCIs and RAIs.
The responses to the RCIs and RAIs in Reference 2 were provided in Reference 3.
Response for RAI GW-5 were provided in Reference 4.
Reference 5 provided supplemental information for RAI HCR-1 regarding the archeology and ecological studies conducted at Monticello Nuclear Generating Plant (MNGP) and clarifying information for RAI GW-5(2g).
In an e-mail from the NRC to NSPM, listed in Reference 6, the NRC transmitted Environmental RAIs.
This submittal provides supplement information for RAI HCR-1 regarding the ecological study for wild rice conducted at MNGP and the responses to the RAIs from Reference 6.
Document Control Desk L-MT-24-029 Page 4 Enclosure Index Enclosure No.
Subject 01 RAI HCR-1 Historic & Cultural Resources 02 RAI Holding Ponds Attachment Index Enclosure No.
Attachment No.
Subject 01 1
Monticello Nuclear Generating Plant, Survey of Culturally Sensitive Plant Species
1 RAI HCR-1 Historic & Cultural Resources Supplement
Monticello Nuclear Generating Plant Docket 50-263 L-MT-24-029 1 Page 1 of 1 Topic: Historic & Cultural Resources Supplement to the RAI HCR-1 Response:
NSPM completed an ecology survey for wild rice (Zizania palustris) on August 2, 2024. The Mille Lacs Band of Ojibwe was invited to participate in the ecology survey for wild rice. The ecology survey for wild rice is provided in Attachment 1. A summary of the report findings is listed below.
The ecological survey was performed by a professional wetland scientist.
The areas with the highest potential for wild rice to grow were identified and depicted in the maps within the attached report.
No wild rice (Zizania palustris) was observed during the ecology survey.
Additionally, NSPM has finalized the updates to the applicable site procedures based on the recent cultural resource activities that have been completed (Reference 5, ML24088A215).
These updates include the State Historical Preservation Office recommendations.
References:
Email from the NRC to Northern States Power Company, a Minnesota corporation (NSPM), d/b/a Xcel Energy, Monticello, Unit 1, Subsequent License Renewal Application Requests for Confirmation of Information Environmental Review dated October 23, 2023, ML23291A109.
Associated Attachments:
- 1. Westwood. 2024. Monticello Nuclear Generating Plant, Survey of Culturally Sensitive Plant Species. Prepared for Northern States Power MN, d.b.a. Xcel Energy. September 4, 2024.
71 p.
1 Monticello Nuclear Generating Plant, Survey of Culturally Sensitive Plant Species
PREPARED BY:
PREPARED FOR:
Northern States Power MN, d.b.a. Xcel Energy SURVEY OF CULTURALLY SENSITIVE PLANT SPECIES Monticello Nuclear Generating Plant Wright and Sherburne Counties, Minnesota SEPTEMBER 4, 2024 L-MT-24-029 Enclosure 1 Page 1 of 71
Survey of Culturally Sensitive Plant Species Monticello Nuclear Generating Plant Wright and Sherburne Counties, Minnesota Prepared For:
Northern States Power MN, d.b.a. Xcel Energy Monticello Nuclear Generating Plant 2807 W County Road 75 Monticello, MN 55362-9601 Prepared By:
Westwood Professional Services 12701 Whitewater Dr. Suite 300 Minnetonka, MN 55343 (952) 937-5150 Project Number: R0046559.00 Date: September 4, 2024 L-MT-24-029 Enclosure 1 Page 2 of 71
Survey of Culturally Sensitive Plant Speciesl Monticello Nuclear Generating Plant September 4, 2024 i l TBPLS Firm #10074302 Table of Contents 1.0 Introduction.................................................................................................... 1 1.1 Location........................................................................................................................................ 1 2.0 Scope of Work................................................................................................ 2 3.0 Methods......................................................................................................... 2 4.0 Results........................................................................................................... 2 5.0 Summary and Conclusion.............................................................................. 3 6.0 References Cited............................................................................................ 3 Table Table 1-1. Sections Containing Project Area....1 Exhibits Exhibit 1: Project Area Location Exhibit 2: Culturally Sensitive Species Observations Overview Map Exhibit 3: Culturally Sensitive Species Observations Map Book Appendices Appendix A: Northern Wild Rice Potential Habitat Observation Photographs L-MT-24-029 Enclosure 1 Page 3 of 71
Survey of Culturally Sensitive Plant Speciesl Monticello Nuclear Generating Plant September 4, 2024 2 l TBPLS Firm #10074302 The Anoka Sand Plain and Mississippi Valley Outwash was previously dominated by bur oak (Quercus macrocarpa) and northern pin oak (Quercus ellipsoidalis); however, drought and land use changes have reduced populations for the previously dominant species of the oak barrens and savannas (MnDNR 2023). Jack pine (Pinus banksiana) was also found along the northern boundary of the region (MnDNR 2023). Wet prairie species were previously identified in the eastern portion of the region (MnDNR 2023). The former wet prairies are mainly bogs with patches of aspen (Populus tremuloides) or other hardwood tree species (White 2020). The current landscape flora consists of a mixture of row crop agriculture, pastures, deciduous forests, and urban developed lands (White 2020).
2.0 Scope of Work The Survey of Culturally Sensitive Plant Species was conducted to delineate populations of eastern red cedar (Juniperus virginiana) and northern wild rice (Zizania palustris) within the MNGP Project Area. Both species are considered culturally significant to the Mille Lacs Band of Ojibwe as well as other Native American tribes. Presence/absence surveys were completed within the entirety of the approximately 2,000-acre MNGP Project Area.
3.0 Methods An initial site visit was conducted on October 23, 2023, by representatives of Xcel, Westwood, and the Mille Lacs Band of Ojibwe for a preliminary review of the Project. This site visit helped to determine the current field conditions and potential of species occurrence in the Project Area.
After the initial site visit, follow up site visits to document the extent of eastern red cedar within the Project Area occurred between December 6th-8th and on December 11th and 13th, 2023.
Singular observations of eastern red cedar were documented as a observation points, while larger populations were surveyed as polygons with an estimated density (Exhibits 2 and 3).
Initial screening of aerial photography was completed to identify potential areas of suitable northern wild rice populations. These areas were investigated in the field for the presence of suitable habitat. Suitable habitat for northern wild rice is generally considered to be locations along lakes, rivers, and streams which contain slow current, shallow water, and muddy substrate.
Wild rice is also highly susceptible to varying water levels.
Initial reconnaissance was conducted for potential habitat for northern wild rice during the site visits in 2023. A follow up investigation for the presence/absence of northern wild rice was conducted during the peak growing season on August 2nd, 2024. Photographs depicting potential habitat locations are included in Appendix A. Locations of photographs are shown in Exhibits 2 and 3.
4.0 Results Eastern Red Cedar Singular observation points of eastern red cedar totaled 1,551 specimens were recorded (Exhibits 2 and 3). An additional 149 population polygons of eastern red cedar with estimated L-MT-24-029 Enclosure 1 Page 5 of 71
Survey of Culturally Sensitive Plant Speciesl Monticello Nuclear Generating Plant September 4, 2024 3 l TBPLS Firm #10074302 densities ranging from four (4) to upwards of 800 specimens were mapped within the Project Area (Exhibits 2 and 3). Approximate total estimates of eastern red cedar in the Project Area total 12,000 specimens.
Many of the larger populations contained eastern red cedars in shrub/sapling form.
Northern Wild Rice No wild rice populations were found within the Project Area. In general, habitat suitability was considered low for locations observed.
Appendix A.
5.0 Summary Westwood identified approximately 12,000 specimens of eastern red cedar within the approximately 2,000-acre Project Area for the Monticello Nuclear Generating Plant. A follow up investigation conducted in the summer of 2024 did not find any northern wild rice populations within the Project Area.
6.0 References Cited Kjerland, T. 2015. Wild Rice Monitoring Field Guide. The University of Minnesota Sea Grant Program, Publication #SH15 (2nd ed.) ISNB 978-0-9965959-0-2.
Kjerland, T. 2015. Wild Rice Monitoring Handbook. The University of Minnesota Sea Grant Program. Publication #SH16.
Minnesota Department of Natural Resources (MnDNR). 2023. Ecological Classification System.
Available online, https://www.dnr.state.mn.us/ecs/222Mc/index.html, accessed November 2023.
United States Environmental Protection Agency (EPA). 2023. Ecoregion Download Files-Minnesota Level IV Shapefile. Available online, https://www.epa.gov/eco-research/ecoregion-download-files-state-region-5#pane-21, accessed October 2023.
White, Dennis. 2020. Ecological Regions of Minnesota: Level III and IV maps and descriptions.
U.S.
Environmental Protection Agency.
Available
- online, https://gaftp.epa.gov/EPADataCommons/ORD/Ecoregions/mn/mn_eco_desc.pdf, accessed October 2023.
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Exhibits Monticello Nuclear Generating Plant Wright and Sherburne Counties, Minnesota L-MT-24-029 Enclosure 1 Page 7 of 71
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Appendix A Northern Wild Rice Potential Habitat Observation Photographs Monticello Nuclear Generating Plant Wright and Sherburne Counties, Minnesota L-MT-24-029 Enclosure 1 Page 27 of 71
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2 RAI Holding Ponds
Monticello Nuclear Generating Plant Docket 50-263 L-MT-24-029 2 Page 1 of 3 Topic: RAI Holding Ponds Requirement:
10 CFR 51.45(b) requires that an environmental report, in part, include a description of the environment affected. The requirements in 10 CFR 51.53(c)(2) requires that postconstruction environmental reports at the license renewal stage, describe in detail the affected environment around the plant, the modifications directly affecting the environment or any plant effluents, and any planned refurbishment activities.
Issue:
In April 2024, the NRC issued for public comment the draft environmental impact statement (DEIS), NUREG-1437, Supplement 26, Second Renewal, Site-Specific Environmental Impact Statement for License Renewal of Nuclear Plants Regarding Subsequent License Renewal for Monticello Nuclear Generating Plant, Unit 1, Draft Report for Comment. The DEIS described a single storage pond being constructed for managing recovered groundwater with elevated tritium. Since issuance of the DEIS, NRC staff was made aware that Xcel Energy is in the process of constructing additional holding/storage ponds as part of the groundwater tritium remediation. Therefore, the DEISs description of the affected environment of the nuclear power plant site needs to be updated to include descriptions of these additional holding/storage ponds.
REQUEST:
Please provide the following information so NRC staff can update the affected environment discussion in the site-specific EIS:
a.) (GEN) Identify the location of the holding/storage ponds and provide a description of the ponds. Include in this description the number of ponds to be constructed, the construction technique for each pond, if they will be lined, overflow prevention/detection measures, size of each pond, when installation will be complete, duration the ponds will be in use, the source of water to be stored in the ponds, and any plans for decommissioning and environmental remediation when all or some ponds are no longer needed.
b.) (HCR) Were any cultural resource surveys conducted prior to construction of the ponds? If so, provide a copy of the survey results, any information related to tribal monitoring, and other related tribal communications.
c.) (WM) Describe how the water will be reused in plant systems or evaporated from the pond(s). If pond evaporation is implemented, describe the changes that will be made to the licensing basis (e.g., Offsite Dose Calculation Manual) to appropriately measure the effluent pathway. If pond evaporation is not implemented, please describe how tritium releases to the air from the pond(s) associated with groundwater remediation will be controlled.
d.) (ECO) Describe anticipated impacts of pond construction on terrestrial, aquatic, and federally protected ecological resources.
Monticello Nuclear Generating Plant Docket 50-263 L-MT-24-029 2 Page 2 of 3 e.) (GW) Provide a discussion of why additional storage is needed, how the need for additional storage relates to progress on remediation of tritium in groundwater, how the rate of pumping tritiated groundwater has changed over time, and the effectiveness of the gradient control pumping and the sheet pile wall.
Response to RAI:
a.) The final design for the additional storage pond has not been completed. The information available at this time is provided below. Currently, the plan is to construct one additional storage pond, Pond 2, which has three cells (2A, 2B, 2C). Pond 2 is located adjacent to and south of the current storage pond. The approximate sizes are provided below:
- Cell 2A: 10.70 million gallons,
- Cell 2B: 8.66 million gallons, and
- Cell 2C: 4.48 million gallons.
The construction of Pond 2 is anticipated to be similar to Pond 1 and consists of common fill excavation and placement, subgrade preparation, geosynthetic clay liner and geomembrane liner installation. Once construction is complete, Pond 2 will have a leak detection system installed and level monitoring to maintain the appropriate freeboard. Pond 2 construction is anticipated to be completed before the end of 2024.
Ponds 1 and 2 will receive groundwater that is pumped from recovery wells from various locations on the Monticello Nuclear Generating Plant (MNGP) site as part of the ongoing groundwater remediation effort. The ponds are anticipated to be used at a minimum throughout the remediation period. As noted earlier, the final design has not been completed. Plans regarding decommissioning and environmental remediation of Pond 2 have not been finalized; however, any decommissioning or remediation activities will comply with applicable federal, state, and local laws and regulations.
b.) There was a Phase 1 Archaeological Survey conducted prior to start of the construction of Pond 2. The survey was conducted by an archeologist that meets the Secretary of Interiors Professional Qualification Standards as stipulated in 36 CFR Part 61. The archeological survey for the project area was approximately 11.96 acres. Shovels tests were completed as part of the archeological survey, and no cultural resources were identified during the archaeological survey. Survey work was completed on May 30, June 3-5, and June 21, 2024. The Mille Lacs Band of Ojibwe (MLBO) was invited to participate in the archaeological survey and a tribal representative was present onsite for a portion of the archaeology survey as a tribal monitor. A courtesy copy of the archaeological report was requested by MLBO, which was sent to the MLBO on August 22, 2024.
Monticello Nuclear Generating Plant Docket 50-263 L-MT-24-029 2 Page 3 of 3 c.) As with Pond 1, Pond 2 will be able to transfer water back to the plant to be used in the condensate storage tank makeup system.
The current plan for the ground water remediation is to reuse the water in the plant or to store the water in the ponds until it is evaporated. Natural evaporation from the existing pond has already been addressed in the Offsite Dose Calculation Manual (ODCM), which was included in the annual radioactive effluent release report submitted to the NRC (ML24135A193, May 14, 2024). When Pond 2 is completed, the ODCM will be updated accordingly.
d.) The construction of Pond 2, which will support current operations and is being performed under the existing operating license, will comply with NSPM procedures and applicable federal, state, and local laws, regulations and permit requirements (hereinafter, standards). Adherence to these standards will avoid and / or mitigate potential impacts to terrestrial, aquatic, and federally protected ecological resources.
Evaluated impacts for Pond 2 are similar to Pond 1, in that it is anticipated to result in a no effect or a small impact to these resources.
e.) The remediation process is an ongoing project at MNGP and NSPM remains dedicated to remediation of tritium in the groundwater and working towards successful completion of the remediation efforts. As stated in previous correspondence (ML24088A215, February 20, 2024) there is a three-prong approach to remediate the groundwater: sheet pile wall, gradient control wells, and removal of contaminated groundwater. The installation of sheet pile wall was completed in November 2023 with the grouting of the wall completed in April 2024. The gradient control wells have been completed and gradient control pumping began in July 2024.
Groundwater removal is in progress and as Pond 1 reaches capacity, additional storage was necessary, which dictated the need for Pond 2.
This year, 2024, there has been significant rainfall in the area (approximately 29 inches, at the time of writing, MDNR 2024), which has kept the river levels high. The groundwater removal pumping rates are variable; however, the overall pumping rate has reduced since 2023. Since the gradient control wells recently started operation (July 2024), additional time is necessary to collect sufficient data to determine the effectiveness; however, preliminary evidence indicates the remediation plan is effective.
References:
MDNR (Minnesota Department of Natural Resources). 2024. Year to Date Precipitation Chart. Retrieved from
<https://www.dnr.state.mn.us/climate/climate_monitor/precipcharts.html?gad_source=1&gclid=EAIaIQobCh MIuJ_PupediAMVqllHAR2w_QdiEAMYASAAEgKz0fD_BwE> (accessed August 2024).
Associated Attachments:
None.