05000275/LER-2011-007, For Diablo Canyon, Unit 1, Inadequate Control Room Envelope Testing Due to Inadequately-Documented In-Leakage Test Data

For Diablo Canyon, Unit 1, Inadequate Control Room Envelope Testing Due to Inadequately-Documented In-Leakage Test Data

ML113190398
Person / Time
Site:	Diablo Canyon
Issue date:	11/14/2011
From:	Becker J Pacific Gas & Electric Co
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
DCL-11-120 LER 11-007-00
Download: ML113190398 (5)

LER-2011-007, For Diablo Canyon, Unit 1, Inadequate Control Room Envelope Testing Due to Inadequately-Documented In-Leakage Test Data

Event date:
Report date:
Reporting criterion:	10 CFR 50.73(a)(2)(ii)(B), Unanalyzed Condition 10 CFR 50.73(a)(2)(i) 10 CFR 50.73(a)(2)(vii), Common Cause Inoperability 10 CFR 50.73(a)(2)(ii)(A), Seriously Degraded 10 CFR 50.73(a)(2)(viii)(A) 10 CFR 50.73(a)(2)(viii)(B) 10 CFR 50.73(a)(2)(iii) 10 CFR 50.73(a)(2)(ix)(A) 10 CFR 50.73(a)(2)(iv)(A), System Actuation 10 CFR 50.73(a)(2)(x) 10 CFR 50.73(a)(2)(v)(A), Loss of Safety Function - Shutdown the Reactor 10 CFR 50.73(a)(2)(v)(B), Loss of Safety Function - Remove Residual Heat 10 CFR 50.73(a)(2)(i)(A), Completion of TS Shutdown 10 CFR 50.73(a)(2)(v), Loss of Safety Function 10 CFR 50.73(a)(2)(i)(B), Prohibited by Technical Specifications
2752011007R00 - NRC Website

text

Pacific Gas and Electric Company November 14, 2011 PG&E Letter DCL-11-120 U.S. Nuclear Regulatory Commission ATTN: Document Control Desk Washington, DC 20555-0001 James R. Becker Site Vice President Diablo Canyon Power Plant Mail Code 104/5/601 P. O. Box 56 Avila Beach, CA 93424 805.545.3462 Internal: 691.3462 Fax: 805.545.6445 10 CFR 50.73 Docket No. 50-275, OL-DPR-80 Docket No. 50-323, OL-DPR-82 Diablo Canyon Units 1 & 2 Licensee Event Report 1-2011-007-00 Diablo Canyon Power Plant - Inadequate Control Room Envelope Testing Due to Inadequately-Documented In-leakage Test Data

Dear Commissioners and Staff:

Pacific Gas and Electric Company (PG&E) submits the enclosed Licensee Event Report (LER) regarding control room envelope in-leakage testing. Both units are affected by this issue. PG&E is submitting this LER in accordance with 10 CFR 50.73(a)(2)(ii)(B).

There are no new or revised regulatory commitments in this report.

This event did not adversely affect the health and safety of the public.

__Sincerel:, ~ ~eZ-James

. Becker mlpy/50428146 Enclosure celene:

Elmo E. Collins, NRC Region IV Michael S. Peck, NRC Senior Resident Inspector James T. Polickoski, NRR Project Manager Alan B. Wang, NRR ProjectManager INPO Diablo Distribution A

member of the STARS (Strategic Teaming and Resource Sharing)

Alliance Callaway. Comanche Peak. Diablo Canyon. Palo Verde. San Onofre. South Texas Project. Wolf Creek

NRC FORM 366 U.S. NUCLEAR REGULATORY COMMISSION APPROVED BY OMB: NO. 3150-0104 EXPIRES: 10/31/2013 (10-2010)

, the NRC may digits/characters for each block) not conduct or sponsor, and a person is not required to respond to, the information collection.

3. PAGE Diablo Canyon Unit 1 05000 275 1

OF 4

4. TITLE Inadequate Control Room Envelope Testing Due to Inadequately-Documented In-leakage Test Data

5. EVENT DATE

6. LER NUMBER

7. REPORT DATE

8. OTHER FACILITIES INVOLVED ISEQUENTIALI REV FACILITY NAME DOCKET NUMBER MONTH DAY YEAR YEAR NUMBER NO.

MONTH DAY YEAR Diablo Canyon Unit 2 05000 323 FACILITY NAME DOCKET NUMBER 09 12 2011 2011 -

7 -

0 11 14 2011 05000

9. OPERATING MODE

11. THIS REPORT IS SUBMITTED PURSUANT TO THE REQUIREMENTS OF 10 CFR §: (Check all that apply) 1 D 20.2201 (b) o 20.2203(a)(3)(i) o 50.73(a)(2)(i)(C)

D 50.73(a)(2)(vii) o 20.2201(d) o 20.2203(a)(3)(ii) o 50.73(a)(2)(ii)(A)

D 50.73(a)(2)(viii)(A)

D 20.2203(a)(1) o 20.2203(a)(4) 12] 50.73(a)(2)(ii)(B)

D 50.73(a)(2)(viii)(B)

D 20.2203(a)(2)(i) o 50.36(c)(1)(i)(A) o 50.73(a)(2)(iii)

D 50.73(a)(2)(ix)(A)

10. POWER LEVEL D 20.2203(a)(2)(ii) o 50.36(c)(1)(ii)(A) o 50.73(a)(2)(iv)(A)

D 50.73(a)(2)(x) 100 o 20.2203(a)(2)(iii) o 50.36(c)(2) o 50.73(a)(2)(v)(A)

D 73.71(a)(4)

D 20.2203(a)(2)(iv)

D 50.46(a)(3)(ii) o 50.73(a)(2)(v)(B)

D 73.71(a)(5)

D 20.2203(a)(2)(v)

D 50.73(a)(2)(i)(A) o 50.73(a)(2)(v)(C)

D OTHER o 20.2203(a)(2)(vi) o 50.73(a)(2)(i)(B) o 50.73(a)(2)(v)(D)

Specify in Abstract below or in PG&E re-performed the inleakage test and is evaluating the test results. PG&E will provide the test results and an assessment of the safety consequences in a supplemental report after completing its test results analysis and cause analysis.

C. Status of Inoperable Structure, Systems, or Components That Contributed to the Event None.

D. Other Systems or Secondary Functions Affected

Inadequate CRE testing rendered both Unit 1 and 2 CRVS trains inoperable. However, the CRVS trains remained capable of performing their normal ventilation functions.

E. Method of Discovery

PG&E investigations in response to questioning from the NRC Senior Resident Inspector about the 2005 CRE in-leakage testing led to the discovery of inadequate testing.

F. Operator Actions

Operators took required actions associated with TS 3.7.10.B, and implemented administrative controls to maintain post-Ioss-of-coolant accident emergency core cooling system leakage at a rate that would ensure operator doses were maintained less than the Final Safety Analysis Report accident analysis results for the highest in-leakage rate reported in the test.

G. Safety System Responses None.

III. Cause of the Problem PG&E will provide the cause in a supplemental report after completing its test results analysis and cause analysis.

IV. Assessment of Safety Consequences

This event did not result in failure of equipment, radiological release to plant personnel or the public. Therefore, this event did not adversely affect the health and safety of the public. PG&E will provide a more detailed assessment ofsafety consequences in a supplemental report after completing its test results analysis and cause analysis.

V. Corrective Actions

PG&E will provide corrective actions in the supplemental report after completing its test results analysis and cause analysis.

VI. Additional Information

A. Failed Components All components functioned as designed.

B. Previous Similar Events

2. DOCKET 05000 275 YEAR 2011

6. LER NUMBER I

SEQUENTIAL I NUMBER 007 REV NO.

4

3. PAGE OF 4

There are no examples of previous similar events at DCPP.