Last reviewed January 2025
Minnesota Issue Guide
Nuclear Waste Storage in Minnesota
This guide is compiled by staff at the Minnesota Legislative Reference Library on a topic of interest to state legislators. It introduces the topic and points to sources for further research. It is not intended to be exhaustive.
Legislative History • Books and Reports • Articles • Additional Library Resources • Groups
Minnesota has two nuclear power generating facilities that have been in operation since the early 1970s: the Prairie Island Nuclear Generating Plant (Unit 1, Unit 2) and the Monticello Nuclear Generating Plant. The issue of how and where to store nuclear waste in Minnesota began with the Prairie Island facility in the late 1980s.
At that time, Prairie Island's high-level spent radioactive waste was stored in stainless steel-lined concrete vaults that were surrounded by cooling water. Under provisions of the Nuclear Waste Policy Act of 1982, the U.S. Government was to develop a site that would accept radioactive waste from the country's nuclear power plants beginning on January 31, 1998. By the late 1980s, with a nuclear waste repository years from completion and Prairie Island facing the prospect of having to close for lack of storage space, Northern States Power (NSP) (now known as Xcel Energy) asked the Minnesota Environmental Quality Board (EQB) for permission to store additional waste in dry casks at the Prairie Island site. In May 1990, the board called for an environmental impact study of the proposed dry cask storage. By spring the following year, the EQB approved and released the Final Environmental Impact Statement: Prairie Island Independent Spent Fuel Storage Installation.
In April 1991, NSP submitted an application for a certificate of need to the Minnesota Public Utilities Commission (PUC), seeking permission to build a dry cask storage facility with up to 48 casks, to be added on an as-needed basis. Hearings were held in front of Administrative Law Judge Allan Klein in November and December 1991. Judge Klein recommended that the PUC deny the certificate of need writing, "The likelihood that the dry cask storage would become permanent is so great that it is appropriate to require legislative authorization if the project must go forward immediately." Despite these recommendations, the Public Utilities Commission ruled that NSP could store the waste, though the number of casks was reduced from 48 to 17.
The Mdewakanton Prairie Island Indian Community and environmental groups opposed to the storage facility appealed the PUC decision to the Minnesota Court of Appeals. The groups argued that the additional storage should be classified as permanent and that under the 1977 Minnesota Radioactive Waste Management Act, NSP needed authorization from the Legislature before the PUC could rule on the matter. On May 28, 1993, the Minnesota Court of Appeals ruled that legislative authorization was needed. The Minnesota Supreme Court refused to hear an NSP appeal, leaving the decision to the Minnesota Legislature. After extensive debate, the 1994 legislature passed a law that permitted NSP to use 17 casks for nuclear waste storage (Laws of Minnesota 1994, chapter 641). This law also forbade the construction of any additional nuclear-powered electrical generating plants in the state (Minnesota Statutes 216B.243, subdivision 3b). Since then, there have been numerous bills introduced seeking to repeal the construction prohibition, however, the moratorium on nuclear power plant construction remains in effect.
The 1994 law required NSP to create a renewable development account and to transfer to that account "$500,000 each year for each dry cask containing spent fuel that is located at the independent spent fuel storage installation at Prairie Island after January 1, 1999" (Laws of Minnesota 1994, chapter 641 article 1, section 10). Funding requirements for the renewable development account have changed several times since 1994 (see the amendments to Minnesota Statutes 116C.779 in the history note, including creation in 2017 of a Renewable Development Account Advisory Group). Current information about the account, known as the Renewable Development Fund, is available from Xcel Energy (and in their annual report) and the Minnesota Public Utilities Commission.
In 1998, after the U.S. Department of Energy failed to meet the January 31, 1998 deadline to accept waste from the country's nuclear power plants, NSP filed a lawsuit in the U.S. Court of Federal Claims against the department, seeking reimbursement for the costs of storing the waste at its Minnesota facilities. The suit was settled in September 2007, with Xcel Energy/NSP being awarded $116 million for costs accrued through 2004. In August 2007, Xcel Energy filed another lawsuit against the U.S. Department of Energy seeking money to cover waste storage costs from 2005 through June 2007. In a July 2011 settlement, Xcel Energy was awarded $100 million for fuel storage costs at Prairie Island and Monticello through 2008. The settlement also would pay for actual costs incurred from 2009 to 2013.
As Prairie Island continued operating, it became evident that the 17 casks would not provide adequate storage space for the nuclear waste generated at the facility. During the 2003 Minnesota legislative session, bills were introduced to allow additional storage space at Prairie Island (House File 775 / Senate File 794). The legislation did not pass during the regular session, but a law was enacted shortly thereafter in a 2003 Special Session (Laws of Minnesota 2003, 1st Special Session, chapter 11). The law required that any future requests for additional nuclear waste storage capacity would be subject to the approval of the Minnesota Public Utilities Commission.
In January 2005, Xcel Energy filed an application for a certificate of need with the Minnesota PUC to build a nuclear waste storage facility at the Monticello plant. The Minnesota Environmental Quality Board approved an environmental impact statement scoping decision that outlined the issues and the alternatives to be examined as part of a required environmental impact study (EIS). A Draft EIS was issued in November 2005 and a Final EIS in March 2006, followed by an Adequacy Determination on July 26, 2006, by the Minnesota Department of Commerce. On September 28, 2006, the PUC approved Xcel Energy's request for nuclear waste storage at the Monticello facility and an order approving the Certificate of Need was issued on October 23, 2006. The decision was effective in June 2007 and construction was planned to begin later that year.
In addition to the state regulatory activities, on March 24, 2005, Xcel Energy filed a license renewal application with the federal Nuclear Regulatory Commission (NRC), seeking a 20-year license renewal for its Monticello facility. The single reactor at the Monticello plant was licensed until 2010. In November 2006, the NRC granted the renewal, extending Monticello's operating license until September 8, 2030. On April 15, 2008, Xcel Energy submitted a license renewal application to the NRC seeking 20-year license extensions for Prairie Island's two reactors. The licenses were to expire in 2013 and 2014. The NRC issued a final EIS related to the license extension in May 2011 and renewed the operating licenses of both Prairie Island reactors in June 2011. Unit 1 is now licensed to operate until 2033 and Unit 2 until 2034.
In May 2008, Xcel Energy announced that it would seek permission from the Minnesota Public Utilities Commission to add more dry casks at the Prairie Island facility. A Final Environmental Impact Statement (EIS) for the Prairie Island projects was issued in late July 2009. In October 2009, the Minnesota Office of Energy Security made a determination that the final EIS was adequate (Adequacy Determination). In December 2009, the Public Utilities Commission issued an order that accepted the Prairie Island EIS and granted the requested dry casks.
The PUC granted approval for the Monticello plant to increase their spent nuclear fuel storage in 2023. Xcel Energy proposed building space for an additional 36 canister vaults, although they expect to only need 14 for operation through 2040. Xcel applied for an operating license renewal in early 2023 to extend the plant’s operation another 20 years. The current operating license is set to expire in September 2030. On December 30, 2024, the U.S. Nuclear Regulatory Commssion renewed Monticello's operating license to expire on September 8, 2050.
In February 2024 Xcel Energy applied for a Certificate of Need to expand dry cask storage at the Prairie Island units. The additional storage would allow for continued operation of the plant to 2054. According to the Star Tribune, Xcel already has 50 casks of spent fuel, expansion plans for 15 more casks under their current license, and will need an additional 34 casks and 2 concrete pads to store waste for 20 more years of operation. The final EIS was released by the Minnesota Department of Commerce in February of 2025.
At the federal level, the search for a permanent U.S. repository for spend nuclear waste continues. As of 2024, the Department of Energy (DOE) is moving forward with a plan to consolidate spent nuclear fuel at one site. This site has yet to be determined and is based on the 2015 consent-based approach to siting facilities for interim storage and disposal. This plan was last updated in 2023 and updates from the DOE are available on their Office of Spent Fuel and High-Level Waste Disposition page.
Legislative History
Significant Books and Reports
Amicus Curiae Brief of Certain Individual Members of the Minnesota House of Representatives and the Minnesota Senate, 1993. (A supplemental friend-of-the-court brief filed with the Court of Appeals.) (Vertical File: A43P)
Annual Report to the Minnesota State Legislature: Renewable Development Fund. Minneapolis: Xcel Energy, 2013- . (TJ807.9.U6 X35)
Background on Nuclear Power in Minnesota. St. Paul: Minnesota Department of Commerce, 2002. (TD899.A8 B33 2002)
Before the Minnesota Public Utilities Commission: Northern States Power Company, Docket No. E002/CN-91-19. St. Paul: Minnesota Department of Public Service, 1991 (TD899.A8 B44 1991)
Bull, Mike. Nuclear Energy and Xcel Energy's 2002 Resource Plan. St. Paul: Minnesota House of Representatives, House Research Department, 2003. (TD899.A8 B85 2003)
Bull, Mike and John Helland. Nuclear Waste Management and the Prairie Island Legislation. St. Paul: Minnesota House of Representatives, House Research Department, 1997. (KFM5780.A8 B85 1997)
Commercial Nuclear Waste: Effects of a Termination of the Yucca Mountain Repository Program and Lessons Learned. Washington, DC: US GAO, 2011.
Consent-Based Siting Process for Federal Consolidated Interim Storage of Spent Nuclear Fuel. Washington, DC: U.S. Department of Energy, 2023.
DOE Nuclear Waste: Better Information Needed on Waste Storage at DOE Sites as a Result of Yucca Mountain Shutdown. Washington, DC: US GAO, 2011.
Energy Planning Report, 2002 Update. St. Paul: Minnesota Department of Commerce, 2003. (HD9502.U63 M561 2003)
Final Environmental Impact Statement Monticello Nuclear Plant Additional Spent Fuel Storage. St. Paul: Minnesota Department of Commerce, 2023.
Final Environmental Impact Statement: Prairie Island Independent Spent Fuel Storage Installation. St. Paul: Minnesota Environmental Quality Board, 1991. (TD899.A8 F56 1991)
Final Environmental Impact Statement: Prairie Island Nuclear Plant Additional Spent Fuel Storage. St. Paul: Minnesota Department of Commerce, 2025.
Final Environmental Impact Statement: Xcel Energy Prairie Island Nuclear Generating Plant. St. Paul, Minnesota Dept. of Commerce, Office of Energy Security, 2009.
Helland, John. Nuclear Waste Transportation. St. Paul: Minnesota House of Representatives, House Research Department, 2002. (HN79.M6 S56 2002)
Helland, John and Linda Taylor. The Prairie Island Nuclear Waste Storage Issue: Questions and Answers. St. Paul: Minnesota House of Representatives, House Research Department, 1994. (TD899.A8 H45 1994)
Helland, John and Mike Bull. Nuclear Waste Dry Cask Storage. St. Paul: Minnesota House of Representatives, House Research Department, 2001. (TD899.A8 H452 2001)
In the Matter of an Application for a Certificate of Need for Construction of an Independent Spent Fuel Storage Installation. State of Minnesota, Court of Appeals, May 28, 1993. (C1-92-2314, C3-92-2315, C9-92-2321) (Vertical File: A43P)
In the Matter of the Application of Northern States Power Company for a Certificate of Need for the Construction of an Independent Spent Fuel Storage Facility.. State of Minnesota, Office of Administrative Hearings, April 10, 1992. (6-2500-5462-2, E-002/CN-91-19.) (Vertical File: A43P)
Legislative Authorization of High Level Radioactive Waste Storage on Prairie Island in the Mississippi: Briefing Paper. (Prepared by Faegre & Benson at the Request of Minnesotans for Nuclear Responsibility). Minnesota, 2004. (Vertical File: A43P)
Legislative Report Concerning Certificate of Need for Dry Cask Storage Facility, E-002/CN-05-123. St. Paul: State of Minnesota Public Utilities Commission, 2007. (TD899.A8 L44 2007)
Legislative Report Concerning Certificate of Need for Dry Cask Storage Facility, Prairie Island Nuclear Generating Plant Independent Spent Fuel Storage Installation. St. Paul: State of Minnesota Public Utilities Commission, 2010. (TD899.A8 L442 2010)
Legislative Report: Report of the Minnesota Public Utilities Commission’s Decision Concerning Additional Spent Nuclear Fuel Storage at the Monticello Nuclear Generating Plant Independent Spent Fuel Storage Installation (SFSI) as Required by Minnesota Statute 116C.83. St. Paul: Minnesota Department of Commerce, 2023. (TD899.A8 L443 2023)
Lehman, Linda. Report to the Minnesota Legislature Regarding the Prairie Island Dry Fuel Storage Project. Minneapolis: L. Lehman & Associates, 1994. (TD899.A8 L44 1994)
Memorandum of Understanding Between the U.S. Nuclear Regulatory Commission and the Prairie Island Indian Community as a Cooperating Agency. 2008.
Minnesota Energy Planning Report 2001. St. Paul: Minnesota Department of Commerce, 2002. (HD9502.U63 M561 2002)
Monticello Spent Fuel Storage Installation: Draft Environmental Impact Statement. St. Paul: Minnesota Dept. of Commerce, 2005. (TD899.A8 M65 2005)
Monticello Spent Fuel Storage Installation: Final Environmental Impact Statement. St. Paul: Minnesota Dept. of Commerce, 2006. (TD899.A8 M66 2006)
Morris, David and John Bailey. The Costs and Benefits of Closing Prairie Island. Minneapolis: Institute for Local Self-Reliance, 1993. (TD899.A8 M67 1993)
Northern States Power Company before the Minnesota Public Utilities Commission, E002/CN-91-19: an index to documents from the Prairie Island Nuclear Power Plant waste storage case, 1991-1993. Minnesota Public Service Dept., 1993. (TD899.A8 N67 1993).
Northern States Power Company before the MN Public Utilities Commission: Application for Certificate of Need for Prairie Island Spent Fuel Storage, Docket No. E002/CN/91-19. Minneapolis: Northern States Power Company, Law Department, April 1991. (TD899.A8 N68 1991) (Vol. 1: Application), (Vol. 2: Environmental Impact Statement)
Northern States Power Company's Prairie Island Nuclear Facilities: An Analysis of Options. St. Paul: Minnesota Department of Public Service, 1994. (TD899.A8 N69 1994)
NSP's Other Nuclear Power Controversy: The Operation and Relicensing of the Monticello Nuclear Power Plant: a Summary of Concerns and a Summary Operating History. Minneapolis, MN: Midwest Office, Izaak Walton League of America, 1993. (TK1344.M6 N77 1993)
Nuclear Power Plant Decommissioning. St. Paul: Minnesota Pollution Control Agency, 2023. (TK9152.2 .N83 2023)
Prairie Island Nuclear Storage Legislative Documents, 1992-1994. (Vertical File: A43P)
Prairie Island Spent Fuel Storage: Fact Book. 1993. (TD899.A8 C66 1993)
Procedures, Considerations and Rules for Siting a Dry Cask Storage Facility. St. Paul: Minnesota Environmental Quality Board, 1994. (TD899.A8 P76 1994)
Recommended Appropriations From the Renewable Development Account. St. Paul: Minnesota Public Utilities Commission, 2018- . (TJ807.9.U6 R43)
Significant Articles
(articles in reverse chronological order)
Orenstein, Walker. "Minnesota lawmakers take a fresh run at lifting the ban on new nuclear plants." The Minnesota Star Tribune, January 24, 2025.
Marohn, Kirsti. "Monticello nuclear plant gets federal approval to keep operating until 2050." Minnesota Public Radio, January 2, 2025.
Fischer, Karen. "Nuclear Power Resurgence. Can efforts ramp up safely to mitigate global warming?" CQ Researcher, October 11, 2024.
Orenstein, Walker. "Xcel asks for more nuclear waste storage to operate Prairie Island until 2050s." Star Tribune, February 8, 2024.
Marohn, Kirsti. "Xcel's plan to store more nuclear waste at Monticello plant gets OK." Minnesota Public Radio, August 24, 2023.
Orenstein, Walker. “Xcel Energy Agrees to Pay Prairie Island $7.5 Million More a Year to Store Spent Nuclear Waste.” MinnPost, March 29, 2023.
Marohn, Kirsti. Could Allowing More Nuclear Power Help Minnesota’s Switch to Carbon-free Electricity? Minnesota Public Radio, March 3, 2023.
Way, Ron. "Times Change. Minnesota's Nuclear Moratorium Must End." Star Tribune, April 10, 2022.
Hubbard, Rob. "Renewable Energy Funding Bill Emerges; Electric Vehicle Rebates OK’d." Session Daily, March 10, 2020.
Catharine Richert. "Environmental, Nuclear Worries Force Prairie Island Tribe to Seek New Lands." Minnesota Public Radio, December 13, 2019.
Marohn, Kirsti. "In Monticello, a City at the Center of the Nuclear Energy Debate." Minnesota Public Radio, October 18, 2019.
Orenstein, Walker. “The Prairie Island Tribe Wants to get to Net-Zero Emissions. Its Biggest Roadblock may be House DFLers.” MinnPost, April 3, 2019.
Moylan, Martin, Elizabeth Dunbar and Kirsti Marohn. "Xcel's New Plan: Coal-Free by 2030, Nuclear Until 2040." Minnesota Public Radio, May 20, 2019.
Hughlett, Mike. "Xcel Seeking New Way to Charge for Nuclear Energy Costs." Star Tribune, March 14, 2018.
Hughlett, Mike. "Minnesota Looks to Rely on Nuclear Power to Meet Electricity Needs for a While: It's Still a Bedrock of the State's Electricity Production." Star Tribune, January 6, 2018.
"NRC to Conduct Open House to Discuss 2016 Performance of Prairie Island Nuclear Generating Plant." NRC News, June 30, 2017.
"Prairie Island Unit 1 Completes 30th Refueling and Equipment Upgrade." Press Release, Xcel Energy, November 21, 2016.
Egerstrom, Lee. "Prairie Island Makes Evacuation Plans." The Circle, August 5, 2016.
Shaffer, David. "Xcel Energy Faces More Big Investments to Keep its Nuclear Units Running: Xcel Faces $487 Million in Upgrades at its Prairie Island Facility by 2020." Star Tribune, March 19, 2016.
Hennagir, Tim. "Xcel Energy Seeks License Amendment to Address Monticello Nuclear Plant Dry Cask Weld Inspection." Monticello Times, May 14, 2014.
Shaffer, David. "Xcel Runs Into Nuclear Economics: A Proposed Power Upgrade to Xcel Energy's Prairie Island Plant is Sidelined Over Cost Uncertainties." Star Tribune, October 14, 2012.
Shaffer, David. "Tribe Faces Fight to Make Case Over Nuclear Storage." Star Tribune, September 28, 2012, p. D1.
Shaffer, David. "Xcel Pauses Prairie Island Upgrade." Star Tribune, March 30, 2012.
Shaffer, David. "Fuel-Storage Pools in State Get Fresh Attention." Star Tribune, March 27, 2011, p. A1.
"Managing Nuclear Waste: Should Spent Fuel be Sent to Yucca Mountain?" CQ Researcher, January 28, 2011.
Kaszuba, Mike. "How Big is Nuclear Danger? Concerned About the Radioactive Waste Piling Up at Two Plants, Red Wing and Monticello Want Help Managing the Risk." Star Tribune, December 10, 2009, P. A1.
Meersman, Tom. "Nuclear Waste Looks Like It Will Be in Minnesota Awhile." Star Tribune, March 7, 2009, p. A1.
Meyers, Mike. "Xcel Wins Suit Over Spent-Fuel Storage: Its NSP Subsidiary Won a Big Judgment Against the U.S. Government on Nuclear Waste Disposal That's Still in Limbo." Star Tribune, September 29, 2007.
Lien, Dennis. "Plant's Nuclear Waste Plan Challenged." St. Paul Pioneer Press, November 15, 2006, p. 6B.
Meersman, Tom. "A Sustained Reaction: Xcel Last Week Was Granted License Renewal for its Monticello Nuclear Power Plant. But Stretching the Life of a Reactor to 60 Years Raises Questions... ." Star Tribune, November 12, 2006, p. D1.
Meyers, Mike. "Xcel's Monticello Nuclear Plant License is Extended to 2030." Star Tribune, November 9, 2006, p. D1.
Lien, Dennis. "Quiet Hearing OKs Nuke Storage: Decision Final in June Unless Legislators Act." St. Paul Pioneer Press, September 29, 2006, p. 3B.
Lien, Dennis. "Judge OKs Nuclear Waste Storage." St. Paul Pioneer Press, August 22, 2006.
Huber, Tim. "Xcel Seeks More Waste Storage." St. Paul Pioneer Press, January 27, 2006, p. 3B.
Huber, Tim. "Generating Debate: Monticello Nuclear Plant Faces Long License Review - With Approval Nearly Certain." St. Paul Pioneer Press, October 17, 2004, p. D1.
Huber, Tim. "Xcel Ups Waste Plan: Greater Storage Sought for Spent Nuclear Fuel." St. Paul Pioneer Press, September 2, 2004, p. C1.
Lien, Dennis. "Pawlenty Signs Nuclear Waste Storage Bill: It Allows Storage at Nuclear Plant Until 2014." St. Paul Pioneer Press, May 30, 2003, p. B3.
Lien, Dennis. "Prairie Island Power Struggle: A Local Indian Tribe Could Decide Whether Xcel's Plant Keeps Operating." St. Paul Pioneer Press, January 24, 2003, p. A1.
"Additional Nuclear Storage Approved." New Laws 2003. St. Paul: Minnesota House of Representatives, Public Information Office, 2003, p. 28-29.
Egerstrom, Lee. "NSP Files Suit Against Energy Department: $1 Billion Claim Centers on Dispute Over Site for Nuclear Waste Disposal." St. Paul Pioneer Press, June 9, 1998.
"Prairie Island Nuclear Storage." Session Weekly May 13, 1994, p. 18-19.
Laszewski, Charles. "Session Draws to Close: Legislature Approves NSP Storage Casks." St. Paul Pioneer Press, May 7, 1994. p. 1A.
Whereatt, Robert. "Full Senate, House Approve NSP Plan for Nuclear Waste. Bill Allows 17 Casks, Pushes Alternative Energy." Star Tribune, May 7, 1994, p. 1B.
Laszewski, Charles. "Legislature Confronts Energy Future: Effects of Decision on Storing Spent Fuel Will be Felt for Years." St. Paul Pioneer Press, February 6, 1994, p. 1A.
NSP Nuclear Storage, 1994-1996: Compilation of News Articles. (Vertical File: A43P)
Prairie Island News Articles, 1993-1994: Compilation. (Vertical File: A43P)
Additional Library Resources
For historical information, check the following codes in the Newspaper Clipping File and the Vertical File:
A43M (Atomic Power Plants - Monticello), A43P (Atomic Power Plants - Prairie Island), A43.5 (Atomic Power Plants - Wastes), C118- Xcel Energy. (For clips prior to 2001, see C118- Northern States Power)
For additional reports at the Legislative Reference Library, use these Library catalog searches:
Nuclear Waste
Groups Involved with this Issue