United States Nuclear Regulatory Commission - Protecting People and the Environment


1.0 Site Identification

Location: Sioux Falls, SD
License No.: 22-08799-02
Docket No.: 030-05004
License Status: Possession Only License
Project Manager: Chad Glenn

2.0 Site Status Summary

The material license that Xcel Energy is seeking to terminate principally applies to material that resides within the steam turbine and auxiliaries of the former Pathfinder nuclear reactor.

The Pathfinder Atomic plant was designed to generate 66 MW of electric energy and operated from August, 1966 to September, 1967. The nuclear fuel was shipped offsite in 1970 and the plant was placed in SAFSTOR in 1971. In September 1972, Pathfinder's Part 50 operating license was terminated and the current Part 30 byproduct license was issued. The reactor and fuel storage facilities were decommissioned in 1991 under Reg. Guide 1.86. In November 1992, NRC amended the license to authorize the unrestricted release of the reactor building, fuel storage building, and waste storage building; to demolish the reactor building; and to authorize the possession of fixed activation products at the Pathfinder site.

During its brief operating period, a relatively small amount of radioactive contamination was found in the steam turbine and auxiliaries. These systems are collectively referred to as the Balance of Plant (BOP) systems to distinguish them from primary power plant systems such as the reactor and its auxiliaries. The BOP was later decontaminated and disconnected from the reactor plant steam source. All contaminated material previously stored in the Turbine Building was removed. The nuclear plant and associated systems were isolated from the turbine building. Steam, reactor feedwater, other lines were cut and capped. The BOP did not receive any additional radioactivity from any source after this period. The residual radioactivity contained within the BOP is a byproduct of materials activated during operation.

The BOP was then integrated into a fossil-fueled peaking plant with gas/oil package boilers suppling steam to operate the existing turbine. The Pathfinder plant that utilized the original nuclear plant's BOP continued to operate on peaking duty until July 13, 2000, when the cooling tower collapsed in a storm. For economic reasons, the decision was made to cease operations of the peaking plant. In February 2003, Xcel Energy notified NRC that it had permanently ceased operating activities at the Pathfinder generating plant. In February 2004, Xcel Energy submitted a decommissioning plan (DP) and license amendment request to authorize decommissioning activities at Pathfinder.

The removal of the radioactive byproduct material within the steam, feedwater, and condensate portions of the BOP is the subject of the Pathfinder decommissioning. According to the licensee, the contamination consists of Co-60 (40 millicuries) and Zn-65 (1 millicurie). This material is in the form of fixed activation products in the BOP.


Xcel Energy is proposing to remediate the contaminated areas to permit unrestricted use of the Pathfinder site. On February 17, 2004, Xcel Energy submitted a DP and license amendment request to NRC to authorize decommissioning activities at the site. On July 16, 2004, NRC staff completed its acceptance review and notified Xcel Energy that the DP was acceptable for a detailed technical review. On August 31, 2004, NRC staff toured the Pathfinder facility and conducted a public meeting in Sioux Falls, South Dakota to discuss site decommissioning and address public questions or concerns. On September 30, 2004, NRC staff requested that Xcel Energy provide additional information in conjunction with its ongoing review of the DP. On December 21, 2004, the licensee submitted its response to the staff's request for additional information and revised its DP. On May 27, 2005, NRC issued Amendment No. 15 authorizing decommissioning in accordance with the approved DP. On January 20, 2006, NRC issued Amendment No. 16 authorizing Xcel Energy's request that the license be amended to include the qualifications that the RSO must meet instead of designating the RSO individually.

3.0 Major Technical or Regulatory Issues


4.0 Estimated Date For Closure

Page Last Reviewed/Updated Friday, May 30, 2014