ML100150327

Response to Disagreement Regarding Cross-Cutting Aspect Associated with NCV IR 05000455-09-003

ML100150327
Person / Time
Site:	Byron
Issue date:	01/14/2010
From:	Stephanie West Division of Nuclear Materials Safety III
To:	Pardee C Exelon Generation Co, Exelon Nuclear
References
EA-09-247
Download: ML100150327 (5)

See also: IR 05000455/2009003

Text

UNITED STATES

NUCLEAR REGULATORY COMMISSION

REGION III

2443 WARRENVILLE ROAD, SUITE 210

LISLE, IL 60532-4352

January 14, 2010

EA-09-247

Mr. Charles G. Pardee

Senior Vice President, Exelon Generation Company, LLC

President and Chief Nuclear Officer (CNO), Exelon Nuclear

4300 Winfield Road

Warrenville IL 60555

SUBJECT: RESPONSE TO DISAGREEMENT REGARDING CROSS-CUTTING ASPECT

ASSOCIATED WITH NON-CITED VIOLATION, BYRON STATION, UNIT 2,

INSPECTION REPORT 05000455/2009003

Dear Mr. Pardee:

On December 18, 2009, Mr. Daniel J. Enright, Exelon Generation Company, LLC (Exelon),

Byron Station, Unit 2, provided a response to an NRC Inspection Report issued on August 7,

2009, concerning activities conducted at your facility. Specifically, the Exelon letter disagreed

with the cross-cutting aspect associated with a non-cited violation (NCV) contained in the

inspection report, namely NCV 05000455/2009003-01, regarding the Failure to comply with

Technical Specification (TS) 3.4.13.B reactor coolant system (RCS) pressure boundary

leakage." In our inspection report, we determined that the primary cause for this finding was

related to the cross-cutting area of Human Performance and its associated component for

Decision Making (H.1(b)), because licensee management personnel concluded that the leak did

not represent reactor coolant pressure boundary leakage due to the closure of an isolation

valve. The Exelon letter indicated that the cross-cutting aspect for the NCV was more closely

associated with a Human Performance component of Resources (H.2(c)).

The Exelon letter indicated that the decision on leak classification was based on available

resources including the site procedures, processes, and training with respect to isolating the line

to eliminate the pressure boundary leakage condition. Exelons position is that the plant was

placed in a safe and conservative configuration as a result of actions to verify that a valve

(2PS9350B) upstream from the leak was closed. Although the valve was closed, valve seat

leakage allowed reactor coolant to continue leaking, albeit at a small rate, through the piping

fault. The licensee indicated that the violation was attributed to the TS not being clear with

regard to the definition of pressure boundary leakage associated with a non-isolable reactor

coolant system leakage through a fault. Exelon contends that the TS was applied as

understood at the time by isolating the fault condition without making an assumption in its

decision making. Therefore, Exelon disagreed with the characterization of the cross-cutting

aspect being classified as Human Performance with an associated component of Decision

Making (H.1(b)). Furthermore, Exelon contends that a more accurate classification and

characterization of the cause for the violation would be the cross-cutting area of Human

Performance with an associated component of Resources (H.2(c)).

C. Pardee -2-

The NRC staff, independent of the original inspectors and approvers, reviewed Exelons basis

for disagreeing with the characterization of the cross-cutting aspect associated with the

violation. From the description of the violation in the associated inspection report, it appears

that:

1. The licensee identified pressure boundary leakage on June 24, 2009, as a pinhole

leak (one drop every 5 minutes) on a welded connection inside the Unit 2

containment. The welded connection is on line 2PS01BB and the line is 3/8 inch in

diameter. This line is a pressurizer liquid sample line and is a non-safety related

non-American Society of Mechanical Engineer code, Class D pipe.

2. The licensee verified that valve 2PS9350B upstream of the leak was closed and that

both containment isolation valves downstream of the leak were closed.

3. Despite the fact that the upstream valve was closed, the leak continued.

4. The Shift Manager made a decision that the leak did not constitute reactor pressure

boundary leakage.

5. Based on that decision, the licensee failed to take the required TS action (be in

Mode 3 within 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br />), resulting in the violation.

Based on this description, it appears that a non-conservative decision was made that had a

direct bearing on the violation. In Appendix A, Components within the Cross-Cutting Areas, to

NRC Inspection Manual Chapter 0305, Operating Reactor Assessment Process, the description

of H.1(b) is as follows:

The licensee uses conservative assumptions in decision making and adopts a

requirement to demonstrate that the proposed action is safe in order to proceed rather

than a requirement to demonstrate that it is unsafe in order to disapprove the action.

The licensee conducts effectiveness reviews of safety-significant decisions to verify the

validity of the underlying assumptions, identify possible unintended consequences, and

determine how to improve future decisions.

Regardless of the perceived adequacy or inadequacy of licensee available resources, including

site procedures, processes, and training with respect to isolating the line to eliminate the

pressure boundary leakage, and in the face of uncertainty (continued leakage), site

management had the option of making a more conservative decision, including affecting repairs

within the TS action time to eliminate the pressure boundary leakage or complying with the

action requirement to be in Mode 3 within 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br />.

Therefore, after careful consideration of the information you provided, we have concluded that

the characterization of the cross-cutting aspect associated with the violation is as stated in the

inspection report. We consider this matter closed.

C. Pardee -3-

In accordance with 10 CFR 2.390 of the NRC's "Rules of Practice," a copy of this letter and your

December 18, 2009, response will be available electronically for public inspection in the NRC

Public Document Room or from the NRC's document system (ADAMS), accessible from the

NRC Web site at http://www.nrc.gov/reading-rm/adams.html.

Sincerely,

/RA/

Steven West, Director

Division of Reactor Projects

Docket No. 50-455

License No. NPF-66

cc: Distribution via ListServ

C. Pardee -3-

In accordance with 10 CFR 2.390 of the NRC's "Rules of Practice," a copy of this letter and your

December 18, 2009, response will be available electronically for public inspection in the NRC

Public Document Room or from the NRC's document system (ADAMS), accessible from the

NRC Web site at http://www.nrc.gov/reading-rm/adams.html.

Sincerely,

/RA/

Steven West, Director

Division of Reactor Projects

Docket No. 50-455

License No. NPF-66

cc: Distribution via ListServ

DOCUMENT NAME: G:\Byron\Byron CCA Disagreement.doc

G Publicly Available G Non-Publicly Available G Sensitive G Non-Sensitive

To receive a copy of this document, indicate in the concurrence box "C" = Copy without attach/encl "E" = Copy with attach/encl "N" = No copy

OFFICE RIII RIII

NAME JCameron:dtp SWest

DATE 1/13/10 1/14/10

OFFICIAL RECORD COPY

Letter to C. Pardee from S. West dated January 14, 2010.

SUBJECT: RESPONSE TO DISAGREEMENT REGARDING CROSS-CUTTING ASPECT

ASSOCIATED WITH NON-CITED VIOLATION, BYRON STATION, UNIT 2,

INSPECTION REPORT 05000455/2009003

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