No. III-09-013 

Contacts: 

Viktoria Mitlyng 630-829-9662 

Prema Chandrathil 630-829-9663 

 May 6, 2009 

 E-Mail: opa3@nrc.gov 

Web site: www.nrc.gov

 

NRC TO DISCUSS 2008 PERFORMANCE ASSESSMENT 

FOR PRAIRIE ISLAND NUCLEAR POWER PLANT 

 The Nuclear Regulatory Commission staff will meet with representatives of Northern States 

Power Co. – Minnesota on Wednesday, May 13, to discuss the agency’s assessment of safety 

performance for last year at the Prairie Island Nuclear Power Plant. The two-unit plant is located in 

Welch, Minn, roughly 50 miles southeast of Minneapolis. 

 The meeting, which will be open to the public, is scheduled to begin at 6:00 p.m. CDT at the 

Prairie Island Training Center Auditorium, 1660 Wakonade Dr. West, in Welch. The NRC staff will 

present the results of the assessment, talk about the NRC and its range of activities, and be available 

to respond to questions or comments from the public before the close of the meeting. 

 “The NRC continually reviews the performance of the Prairie Island plant and the nation’s 

other commercial nuclear power facilities,” NRC Region III Administrator Mark Satorius said. 

“This meeting allows us to discuss our annual assessment of safety performance with the company 

and area residents. One of NRC’s main goals is to explain to people in the community how the 

agency regulates nuclear power plants.” 

 A letter sent from the NRC Region III Office to plant officials addresses the performance of 

the plant during the period and will serve as the basis for the meeting discussion. It is available on 

the NRC Web site at: http://www.nrc.gov/NRR/OVERSIGHT/ASSESS/LETTERS/prai_2008q4.pdf

The NRC utilizes a combination of color-coded inspection findings and performance 

indicators to measure plant performance. The colors go from “green” to “white,” “yellow” or “red,” 

commensurate with the safety significance of the issues involved. 

 

 The NRC’s assessment concluded that overall Prairie Island operated safely in 2008. Prairie 

Island Unit 2 performed at a level that required no additional NRC oversight. However, Unit 1 had 

one “white” finding of low to moderate safety significance that will result in additional NRC 

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oversight. This finding was associated with the failure to control the position of a normally open 

valve for the Unit 1 auxiliary feedwater system. The valve was inadvertently left closed, causing a 

pump to fail to operate as required following a reactor shutdown. The auxiliary feedwater system is 

a backup system that provides water to the steam generators. Each reactor at Prairie Island has two 

auxiliary feedwater pumps which can supply water to the steam generators. The plant took 

immediate corrective actions. The NRC will conduct a supplemental inspection to make sure the 

causes of the finding have been understood and problems associated with the finding have been 

resolved. 

 The NRC letter also states that another inspection finding is still under review. It involved 

the shipment of radioactive material from Prairie Island to Waltz Mill, Pa, which exceeded 

radioactivity limits established by the NRC and the Department of Transportation. After the final 

significance of this issue is determined, the NRC will determine the appropriate level of additional 

oversight. 

 In addition to the supplemental inspection, the NRC will continue to conduct very detailed 

routine inspections for plants that are performing well. Routine inspections are performed by two 

NRC Resident Inspectors assigned to the plant, and inspection specialists from the Region III Office 

in Lisle, Ill. Among the areas of plant operations to be inspected this year by NRC specialists are 

emergency preparedness, radiation protection and the independent spent fuel storage installation. 

 Current performance information for Prairie Island is available on the NRC’s web site at: 

http://www.nrc.gov/NRR/OVERSIGHT/ASSESS/PRAI1/prai1_chart.html (Unit 1) and 

http://www.nrc.gov/NRR/OVERSIGHT/ASSESS/PRAI2/prai2_chart.html (Unit 2). 

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