EA-97-073 - Prairie Island 2 (Northern States Power Company)

April 30, 1997

EA 97-073

Mr. M. D. Wadley, Vice President
Nuclear Generation
Northern States Power Company
414 Nicollet Mall
Minneapolis, MN 55401


Dear Mr. Wadley:

This refers to the inspection conducted from January 8 through February 20, 1997, at the Prairie Island Nuclear Generating Plant, Unit 2 facility. This inspection included a review of the circumstances surrounding the movement of a twenty-one ton reactor coolant pump motor rotor and bracket over a fully fueled reactor vessel. The written results of this inspection were provided to you on February 25, 1997. A predecisional enforcement conference was conducted on March 18, 1997.

Based on the information developed during the inspection and the information that you provided during the conference, the NRC has determined that a violation of NRC requirements occurred. The violation is cited in the enclosed Notice of Violation and the circumstances surrounding it are described in detail in the subject inspection report. On February 3, 1997, due, in part, to a miscommunication between members of your maintenance, engineering, and operations departments, your staff improperly executed the movement of a heavy load (a twenty-one ton reactor coolant pump motor rotor and bracket) over irradiated fuel in a reactor vessel with the reactor head removed. This activity was performed without establishing containment integrity, since both maintenance and personnel airlocks were open.

The safety significance of this event pertains to the failure to establish containment integrity. If the heavy load had fallen into the reactor vessel, the potential existed that the refueling cavity seal and several fuel assemblies could have been damaged. While the refueling cavity was flooded to the maximum level during the transfer, significant damage to the cavity seal could have caused the refueling cavity to have been drained. If the refueling cavity was drained, and several fuel assemblies were damaged, then a significant amount of fission products could have been released outside of the containment.

The regulatory significance of this event pertains to the failure of at least two administrative barriers. The first was the significant failure to follow procedures. Specifically, your staff did not refer to procedure D58, "Control of Heavy Loads," prior to the lift. Maintenance workers did not follow guidance in the procedure governing the evolution which instructed them to comply with procedure D58, and the reactor coolant pump system engineer was not knowledgeable of the D58 procedural requirements. The second control failed when your staff did not establish containment integrity prior to moving a heavy load over the open reactor vessel. These administrative barriers are important since the containment polar crane is not single failure proof. While the system engineer was directly responsible for the heavy load transfer, the safe passage should have been the responsibility of all involved personnel. It is especially imperative that operations personnel fully understand activities which need control room approval to ensure that these activities are safely completed.

The administrative controls that should have been in place to allow the containment to perform its safety function failed. If the reactor coolant pump motor rotor had fallen into the reactor vessel it could have caused a significant release of fission products outside of containment. Therefore, this violation has been categorized in accordance with the "General Statement of Policy and Procedure for NRC Enforcement Actions" (Enforcement Policy), NUREG-1600 as a Severity Level III violation.

In accordance with the Enforcement Policy, a base civil penalty in the amount of $50,000 is considered for a Severity Level III violation. Because your facility has been the subject of escalated enforcement actions within the last two years1, the NRC considered whether credit was warranted for Identification and Corrective Action in accordance with the civil penalty assessment process in Section VI.B.2 of the Enforcement Policy. The NRC determined that credit for Identification was warranted because the error was promptly identified and reported by alert shift supervision on February 4, 1997. The shift supervisor realized the error when maintenance personnel attempted to return the reactor coolant pump motor rotor to the reactor coolant pump vault using the incorrect path traversed on February 3, 1997. The NRC determined that credit for Corrective Action was warranted based on the results of the licensee's root cause analysis and prompt corrective actions. The reactor coolant pump system engineer was instructed on the requirements of D58, and subsequently prepared a procedure with the appropriate controls to return the pump motor rotor to the reactor coolant pump vault. This transfer was successfully completed. Training provided to maintenance workers on the event and on heavy load requirements was effectively completed. Finally, the Error Reduction Task Force Investigation initiated to review this event successfully identified program weaknesses and recommended several programmatic improvements.

Therefore, to encourage prompt identification and comprehensive correction of violations, I, after consultation with the Director, Office of Enforcement, have been authorized to issue the enclosed Notice of Violation with no Civil Penalty in this case. However, significant violations in the future could result in a civil penalty.

You are required to respond to this letter and should follow the instructions specified in the enclosed Notice of Violation when preparing your response. The NRC will use your response, in part, to determine whether further enforcement action is necessary to ensure compliance with regulatory requirements.

In accordance with 10 CFR 2.790 of the NRC's "Rules of Practice," a copy of this letter, its enclosure, and your response will be placed in the NRC Public Document Room.

Sincerely, Original signed by A. Bill Beach Regional Administrator

Docket No. 50-306
License No. DPR-60

Enclosure: Notice of Violation

cc w/encl:
Plant Manager, Prairie Island
John W. Ferman, Ph.D.,
Nuclear Engineer, MPCA
State Liaison Officer, State of Minnesota

State Liaison Officer,
State of Wisconsin
Tribal Council
Prairie Island Dakota Community

Northern States Power Company Docket No. 50-306 Prairie Island Nuclear Generating Plant License No. DPR-60 EA 97-073

During an NRC inspection conducted from January 8, 1997 through February 20, 1997, a violation of NRC requirements was identified. In accordance with the "General Statement of Policy and Procedure for NRC Enforcement Actions," NUREG-1600, the violation is listed below.

10 CFR 50, Appendix B, Criterion V, states, in part, that activities affecting quality shall be prescribed by documented instructions, procedures, or drawings, of a type appropriate to the circumstances and shall be accomplished in accordance with these instructions, procedures, or drawings.

Technical Specification 6.5.C.3 requires that detailed written procedures shall be prepared and followed for activities that perform preventative or corrective maintenance of plant equipment and systems that could have an effect on nuclear safety.

Procedure D58, revision 25, dated December 19, 1996, "Control of Heavy Loads," step 5.3.1.C.1, required that with the reactor head removed, loads greater than 2100 pounds shall not be moved within 15 horizontal feet of the irradiated fuel without specific written procedures.

Additionally, Procedure D58, Step 5.8, required, in part, containment isolation by closure of the containment purge and inservice purge valves and by closing at least one door in each of the two air locks before performing a heavy load lift over irradiated fuel in the reactor vessel.

Contrary to the above, on February 3, 1997, the licensee moved a heavy load greater than 2100 pounds (the No. 22 reactor coolant pump motor rotor and upper bracket) within 15 horizontal feet of irradiated fuel that was in an open reactor vessel without a written procedure. In addition, both doors of the containment maintenance and personnel airlocks were open and the inservice purge system was operating.

This is a Severity Level III violation (Supplement 1).

Pursuant to the provisions of 10 CFR 2.201, Northern States Power Company is hereby required to submit a written statement or explanation to the U.S. Nuclear Regulatory Commission, ATTN: Document Control Desk, Washington, D.C. 20555 with a copy to the Regional Administrator, Region III, and a copy to the NRC Resident Inspector at the facility that is the subject of this Notice, within 30 days of the date of the letter transmitting this Notice of Violation (Notice). This reply should be clearly marked as a "Reply to a Notice of Violation" and should include for each violation: (1) the reason for the violation, or, if contested, the basis for disputing the violation, (2) the corrective steps that have been taken and the results achieved, (3) the corrective steps that will be taken to avoid further violations, and (4) the date when full compliance will be achieved.

Your response may reference or include previous docketed correspondence, if the correspondence adequately addresses the required response. If an adequate reply is not received within the time specified in this Notice, an order or a Demand for Information may be issued as to why the license should not be modified, suspended, or revoked, or why such other action as may be proper should not be taken. Where good cause is shown, consideration will be given to extending the response time.

Under the authority of Section 182 of the Act, 42 U.S.C. 2232, this response shall be submitted under oath or affirmation.

Because your response will be placed in the NRC Public Document Room (PDR), to the extent possible, it should not include any personal privacy, proprietary. or safeguards information so that it can be placed in the PDR without redaction. If personal privacy or proprietary information is necessary to provide an acceptable response, then please provide a bracketed copy of your response that identifies the information that should be protected and a redacted copy of your response that deletes such information. If you request withholding of such material, you must specifically identify the portions of your response that you seek to have withheld and provide in detail the bases for your claim of withholding (e.g., explain why the disclosure of information will create an unwarranted invasion of personal privacy or provide the information required by 10 CFR 2.790(b) to support a request for withholding confidential commercial or financial information). If safeguards information is necessary to provide an acceptable response, please provide the level of protection described in 10 CFR 73.21.

Dated at Lisle, Illinois
this 30th day of April 1997

1 A Severity Level III violation with a $50,000 civil penalty was issued on January 23, 1997 (EA 96-402) and a Severity Level III violation with no civil penalty was issued on October 1, 1996 (EA 96-266).

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