United States Nuclear Regulatory Commission - Protecting People and the Environment

EA-99-212 - Beaver Valley 2 (Duquesne Light Co.)

October 21, 1999

EA 99-212

Mr. J. E. Cross
Generation Group
Duquesne Light Company
Post Office Box 4
Shippingport, Pennsylvania 15077

SUBJECT: NOTICE OF VIOLATION
(NRC Inspection Report No. 50-412/99-07)

Dear Mr. Cross:

This refers to the NRC special team inspection conducted from July 20 through July 29, 1999, at the Beaver Valley Unit 2 Power Station, the results of which were discussed with you at an exit meeting on July 29, 1999. The inspection was conducted, in part, to review the macro biological fouling (biofouling) problems which affected the service water system supply to the heat exchangers for both emergency diesel generators (EDGs). The inspection report was forwarded to you on September 7, 1999. During the inspection, three apparent violations of NRC requirements associated with the biofouling problems were identified. In our September 7, 1999 letter, we offered you the opportunity to either respond in writing to the apparent violations addressed in this inspection report or request a predecisional enforcement conference. In a letter dated October 7, 1999, you provided a response to the apparent violations.

Based on the information developed during the inspection and the information provided in your October 7, 1999 response, the NRC has determined that two violations of NRC requirements occurred. The violations are cited in the enclosed Notice of Violation (Notice) and the circumstances surrounding them are described in detail in the subject inspection report. The violations involve: (1) the failure to implement corrective actions to prevent biofouling of the service water system, despite prior opportunities to do so; and (2) the failure to provide adequate acceptance criteria in the procedure for chemical treatment of the service water system. These violations resulted in fouling of the EDG heat exchangers.

The 2-2 EDG was declared inoperable during a surveillance test on July 14, 1999, when service water flow to the EDG's heat exchanger decreased to 1070 gpm, which was below the design basis of 1170 gpm set forth in your Updated Final Safety Analysis Report. Subsequent inspection revealed that service water flow to the heat exchanger was reduced because about 3 gallons of biological fouling, primarily in the form of Zebra mussels, was blocking about 90 percent of the heat exchanger's tube sheet. The biological fouling was the result of a bulk chemical treatment of the service water system on July 7, 1999.

Although you were aware of the potential for biofouling of plant systems as early as 1990, and developed a plan for preventive and corrective actions in 1995, the planned actions were not effectively implemented. The routine and bulk biocide treatments were not applied at an appropriate frequency to prevent infestation of Zebra mussels in the service water system. As a result, when a bulk biocide treatment was applied to the service water system in July 1999, the mussels in portions of the system accumulated in the 2-2 EDG heat exchanger during surveillance testing of the EDG. The heat exchanger for the other EDG did not clog at the same time because the intended biocide concentration was not applied to the other service water train due to an error in implementation of the chemical treatment procedure. Subsequently, the procedure was reperformed for the other train and biofouling occurred in the heat exchanger for the other EDG. The plant was shutdown at the time of this occurrence. You had an additional opportunity to address the biofouling problem in 1998 when the zebra mussel population increased at the service water intake structure. However, no changes were made to the action plan and an opportunity was missed to identify the inadequate controls for preventing biofouling. The failure to promptly identify and correct the biofouling of the service water heat exchangers constitutes a violation of 10 CFR 50, Appendix B, Criterion XVI, "Corrective Actions."

Further, your chemical treatment procedure did not contain quantitative or qualitative acceptance criteria to determine the adequacy of service water flow to the EDG heat exchangers following the biocide treatments. As a result, the degraded condition was not identified until 7 days after the biocide treatment when a surveillance test of the EDG was conducted. The inadequacies in the procedure delayed the identification of the degraded condition and constitute a violation of 10 CFR 50, Appendix B, Criterion V, "Procedures."

These violations are potentially risk significant because the heat exchangers for both diesel generators would have become biofouled if the planned chemical treatment procedure had been followed. In your October 7, 1999 response, you provided the results of an analysis which indicated that EDG 2-2 was degraded but operable. Specifically, you concluded that the minimum expected flow through the EDG heat exchangers would have been sufficient for the EDGs to perform their safety function if called upon during the period in question. Based on review of this information, the NRC agrees with your determination that the EDG was operable during the period in question. Therefore, there was no violation of Technical Specifications. However, given the significance of the flow degradation, and the credible potential for simultaneous failure of both EDGs, it was not assured that the EDGs would have been able to perform their intended safety function under different circumstances (i.e., higher river water temperature). Therefore, these violations represent a Severity Level III problem in accordance with the "General Statement of Policy and Procedure for NRC Enforcement Actions" (Enforcement Policy), NUREG-1600.

In accordance with the Enforcement Policy, a base civil penalty in the amount of $55,000 is considered for a Severity Level III violation or problem. Because your facility has been the subject of escalated enforcement action within the last 2 years(1), 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. Credit is warranted for identification because the biofouling problem was identified during your surveillance test of the emergency diesel generator and, subsequently, you performed a root cause analysis which identified that your Zebra mussel control program was ineffective and the implementing procedures were inadequate. Credit is also warranted for corrective action because your actions, as described in your October 1999 letter, were considered prompt and comprehensive. These actions included, but were not limited to: (1) restoration of the EDG heat exchangers and inspection of other heat exchangers for biofouling; (2) revisions to chemical treatment and surveillance procedures; (3) determination of the optimum frequency for biocide treatments and incorporation of the treatments into the work control schedule; and (4) plans to review the effectiveness of the Zebra mussel control program.

Therefore, to encourage prompt identification and comprehensive correction of violations, I have been authorized, after consultation with the Director, Office of Enforcement, to not propose a civil penalty in this case. However, significant violations in the future could result in a civil penalty.

The NRC has concluded that information regarding the reason for the violations, the corrective actions taken and planned to correct the violations and prevent recurrence is already adequately addressed on the docket in your letter dated October 7, 1999. Therefore, you are not required to respond to this letter unless the description therein does not accurately reflect your corrective actions or your position. In that case, or if you choose to provide additional information, you should follow the instructions specified in the enclosed Notice.

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

Sincerely,

ORIGINAL SIGNED BY
JAMES T. WIGGINS FOR:

Hubert J. Miller
Regional Administrator

Docket No. 50-412
License No. NPF-73

Enclosure: Notice of Violation

cc w/encl:
F. von Ahn, Acting Senior Vice President, Nuclear Services Group
L. W. Myers, Executive Vice President, Generation Group
K. Ostrowski, Vice President, Nuclear Operations Group and Plant Manager
W. Pearce, General Manager, Nuclear Operations Unit
W. Kline, Manager, Nuclear Engineering Department
M. Pearson, Manager, Quality Services Unit
M. Ackerman, Manager, Safety & Licensing Department
B. Davis, Acting Manager, System and Performance Engineering
J. A. Hultz, Manager, Projects and Support Services, First Energy
M. Clancy, Mayor, Shippingport, PA
Commonwealth of Pennsylvania
State of Ohio
State of West Virginia


ENCLOSURE

NOTICE OF VIOLATION

Duquesne Light Company
Beaver Valley Unit 2 Power Station
Docket No. 50-412
License No. NPF-73
EA 99-212

During an NRC inspection completed on July 29, 1999, violations of NRC requirements were identified. In accordance with the "General Statement of Policy and Procedure for NRC Enforcement Actions," NUREG-1600, the violations are listed below:

A.   10 CFR Part 50, Appendix B, Criterion XVI, requires, in part, that measures be established to assure that conditions adverse to quality, such as deficiencies, deviations, and nonconformances are promptly identified and corrected.

Contrary to the above, as of July 1999, the licensee did not take adequate measures to assure that a condition adverse to quality involving macro biological fouling (biofouling) of the service water system was promptly identified and corrected, despite prior opportunities to do so. Specifically:

1.   Between 1990 and 1995, the licensee identified the potential for zebra mussel infestation in plant systems and developed a plan for preventive and corrective actions. However, these actions were not fully integrated into procedures and, as a result, the actions were not fully implemented.

2.   In February 1998, zebra mussels were identified in the plant intake pump bays; however, no revisions were made to the plan to control zebra mussel infestation and no action was taken to ensure that the planned actions were effectively implemented.

The failure to consistently perform routine biocide treatments in 1998 and 1999, coupled with the performance of ineffective bulk biocide treatments during this period, allowed zebra mussels to accumulate in the service water system. As a result, following a bulk biocide treatment in July 1999, the heat exchanger for Emergency Diesel Generator (EDG) 2-2 became fouled with zebra mussels which significantly degraded the cooling water flow through the heat exchanger. (01013)

B.   10 CFR Part 50, Appendix B, Criterion V, Instructions, Procedures, and Drawings, requires, in part, that procedures shall include acceptance criteria for determining that important activities have been satisfactorily accomplished.

Contrary to the above, as of July 7, 1999, Operating Procedure 2OM-30.4.M, "BV-2 Asiatic Clam Chemical Treatment Program," Revision 7, did not include adequate acceptance criteria for determining that important activities had been satisfactorily accomplished. Specifically, the procedure did not contain quantitative or qualitative acceptance criteria for verifying service water flow through all of the heat exchangers, nor did the procedure require post-treatment monitoring of the heat exchangers for indication of flow degradation. Consequently, use of the procedure on July 7, 1999, to clean the service water piping of zebra mussels resulted in biofouling of the 2-2 EDG service water heat exchanger and restricted the water flow to 1070 gpm, which was below the design basis minimum requirement of 1170 gpm. This flow degradation remained undetected until an EDG surveillance test was conducted on July 14, 1999. (01023)

These violations constitute a Severity Level III problem (Supplement I).

The NRC has concluded that information regarding the reason for the violations, the corrective actions taken and planned to correct the violation and prevent recurrence and the date when full compliance will be achieved is already adequately addressed on the docket in a letter from the Duquesne Light Company (Licensee), dated October 7, 1999. However, you are required to submit a written statement or explanation pursuant to 10 CFR 2.201 if the description therein does not accurately reflect your corrective actions or your position. In that case, or if you choose to respond, clearly mark your response as a "Reply to a Notice of Violation," and send it to the U.S. Nuclear Regulatory Commission, ATTN:  Document Control Desk, Washington, D.C. 20555 with a copy to the Regional Administrator, Region I, 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).

If you contest this enforcement action, you should also provide a copy of your response to the Director, Office of Enforcement, United States Nuclear Regulatory Commission, Washington, DC 20555-0001. If you choose to provide a response, under the authority of Section 182 of the Act, 42 U.S.C. 2232, the response shall be submitted under oath or affirmation.

If you choose to respond, your response will be placed in the NRC Public Document Room (PDR). Therefore, to the extent possible, the response should not include any personal privacy, proprietary, or safeguards information so that it can be placed in the PDR without redaction.

In accordance with 10 CFR 19.11, you may be required to post this Notice within two working days.

Dated at King of Prussia, Pennsylvania
this 21st day of October 1999


1.   A Severity Level III violation and a $55,000 civil penalty was issued on January 6, 1998 (EA 97-517).

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