IR 05000237/1996013
| ML17187A996 | |
| Person / Time | |
|---|---|
| Site: | Dresden  |
| Issue date: | 05/30/1997 |
| From: | Beach A NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION III) |
| To: | Jamila Perry COMMONWEALTH EDISON CO. |
| Shared Package | |
| ML17187A997 | List: |
| References | |
| 50-237-96-13, 50-249-96-13, EA-96-391, NUDOCS 9706050017 | |
| Download: ML17187A996 (5) | |
Text
SUBJECT:
.NOTICE OF VIOLATION May 30, 1997.
CNRC INSPECTION REPORT 50-237/96013(DRP);_50-249/96013(DRP))
Dear Mr. Perry:
This refers to the inspection conqucted from September 1 through October 18.
1996 at 'the: Dresden Station's Unit.2 and 3 facilities. This inspection included a review of the circumstances surrounding the failure to maintain the
- primary containment leakage within the acceptable limits between January and
'.. May 1995. This was Teported to the NRC in Licensee Event Report 50-249/95007.
. Revisions 0. 1 and 2.
~Leakage Limit Exceeded Due to Valve Internal Damage Caused by Manual Operation of-Motor Operated Valves." The* written results of
- this inspection were provided to,you on Decemb~_r 31. 1996.
- _ * Based on the *i nformat i oh developed during the inspection and the information.
that you provided in a letter from the** Dresden Station dated.January 28. 1997. *
the NRC has determined. that a violation of NRC.. requi rements occurred.. The violation is cited in the enclosed Notice of Violation (Notice) and the
. circumstances* surrounding it are described in detail in the subject inspection report.
In June. 1995; you determined that the Unit a*inboard and outboard main steam line drain primary containment isolation valves were leaking greater than the local leak rate *test equipm*ent could measure.
It was subsequently determined that between January 16.-1995. and May 28. 1995; with the reactor.critical. primary containment leakage.was greater than 60 percent of La due to leakage past the Unit 3 inboard and outboard m~in steam line
- drain primary containment isolation valves. 3-220-1 and 3-220~2. Main steam line drain isolatiori valves 3-220-1 and 3-220-2 are Anchor Darling isolation.
valves* subject to Type Band C tests. The inboard valve leakage was.caused by**
low spots on the valve seat from the poor alignment.of the disk to seat. The
.outboard valve leakage was.caused.by the missing lower wedge of the valve disk and a bent stem.
The safety significance of this event was related to the potentially i~crease~
\\
radiological conseq~ences both on and off-site: Initial calculations
- , determined that under worst case conditions. dose limits established by 10 CFR
\\ l Part 50. *Appendix A. General Design Criterion 19.for control room operators and by 10.CFR Part 100 for the Exclusion Area Boundary (EAB) and the Low Population Zone (LPZ) would have been exceeded during a Design Basis Accident.
9706050017 970530 PDR ADOCK 05000237 G
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- 2eaa.
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J. Subsequent assessments performed by your staff using expected containment accident parameters and expected main steam line drain leakage values concluded that control room and offsite doses were lower than the* initial *
calculations arid were within the regulatory limits.* Several weaknesses were identified which contributed to the isolation valves leaking. These.
weaknesses included the lack of experience on the Anchor Darling double disk gate valves prior to installation. poor maintenance instructions for the Anchor Darling valve assemblies. and the inadequate design modification process which failed to identify that low torque values would damage the valve during normal handwheel operation.
If more attention had existed in these areas. and no valve damage had occurred. then containment integrity could have been maintained. *
This issue is of concern beca.use the inadequate design modi fi cation review and
- *poor maintenance instructions for the installation of the primary containment isolation valyes resulted in the degradation of the primary.containment
.
system. This degradation had the potential for causi~~ cont~ol room and off-site radiological doses to exceed regulatory limits during the Design Basis Accident. Therefore. this violation has been categorized in a~cordance with the "General Statement of Policy and Procedure for NRC Enforcement Actions"
- cEnforcement Policy). NUREG-1600 at Severity Level III.
In accordance with the Enforcement Policy, a b~se.civil penalty in the amount*
of $50.000 is considered for a Severity level III violation that occurred before November 12. 1996. *Because your facility has been.the subject*of escalated enforcement acti ans w.ithi n the last 2 years.1 the NRC considered whether* credit was warranted for Identification and.Corrective Action in*
- accordance with the civil penalty a~sessment protess in ~ection VI.B.2 of the Enforcement Policy.
The NRC. determined that c,redit for Identification was warranted because in Jurie 1995. your staff identified that the Unit 3 tnboard and* outboard main steam line drain primary containment isolation valves; were leaking greater than the local leak rate test.CLLRT) test *equipment could measure.
Your staff then determined that this leakag~ ~as.not withi~ the.
acceptable limits.for pr-imary containment leakage. and subsequently wrote a l i censee event report. The' NRC determined that credit for Corrective* Act i oil was warranted based on your prompt and thorough corrective actions.
Your determination of the root cause was considered methodical and thorough.
The
. corrective actions were comprehensive and included: the repair and
.
replacement of the inboard and outboard valves. respectively; a revision of multiple procedures to formally control motor operated*valve handwheel usage:
a review of Unit.2* and 3 valves susceptible to damage from handwheel use:
evalu~tion..test. and inspection to verify valve integrity: training for.
operations and-maintenance personnel on the manual operation of motor operated valves:*and the development of a list of allowable generic torque values for 1 A Severity Level Ill violation with a $50,000 Civil Penalty was i'ssued on June 13, 1996 (EA 96-115); a Severity Level Ill violation with a $50,000 Civil Penalty was issued on December 5, 1995 (EA 95-214); a Severity Level Ill violation with a $100,000 Civil Penalty was issued on April 5, 1995 (EA 95-030).
- J.. safety related and balance of plant motor operated valves for use during handwhee l op.er at ion.
Your root cause evaluation and subsequent corrective actions were comprehensive; however. the valve failures were considered preventable and were indicative of a weakness in your motor operated valve design control process.
- Therefore. to encourage prompt identification and comprehensive correction of violations. I have been authorized. after consultation with the Director.
Office of Enforcement. not to 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 th.e violation.
the corrective actions taken and planned to correct the ~iolatjon and prevent recurrence is already adequately addressed on the docket in Inspection Report.
Nos.
so~237;249/96013CDRP). LER 249/95007. and your response to the inspection report dated January 28. 1997. Therefore. you are not required to respond to t~e enclosed Notice unless the description in the docketed materials *
referenced above do not accurately reflect your corrective actions or your positioQ.
In that case. or if you choose to provide a~ditional information; you should followthe i nstructi ans specified in the enclosed Nati ce.
Finally;. we note that there is a discrepancy between Revision 2 of LER.
.
249/95007 and your January 28. 1997 letter concerning your staff's initial_~
assess~ent of contrql room operator dos~s and EAB. ahd LPZ doses under worst
- case conditions..
Your LER*states that these dose limits would have been exceeded (page 5. *second paragraph in Section; 0). while your January'-28 'letter.
.. states.that these doses might have been exceeded (page 1. second paragraph).
While.this might*have been an oversight in word choice. I want to emphasize to
. you the importance of ensuring that information that you provide to the*
. Cammi ss ion be complete and accurate in a 11 material respects. especi a 11 y when that information is being used for regulatory decision-making. *Therefore. we
- requ~st that you respond to this discrepancy and submit formal *clarification on th_i s issue.
J. In accordance with 10 CFR 2. 790 of the NRC' s "Rules of Practice." a copy of this letter and its enclosure will be placed in the Public Document Room (PDR).
Sincerely
.
Original signed by A. Bill Beach A. Bill Beach Regi ona*l Administrator Ddcket Nos.
50-237: 50~249 License Nos. DPR-19; DPR-25 Enclosure:
Notice.of Violation cc w/encl:
T. J. Maiman. Senior Vice President Nucl~ar Operations Division
D. A. Sager. Vice President.
Generation Support
- H. W. Keiser. Chief Nuclear *
Operating Of~icer *
.
T. Nauman. Station*Manager Unit 1
- M*.. Heffley_, Statton Manager Units 2 an.d *3 F. Spangenberg. RegulatoryAssurance Manager. *
I. Johnson. Acting. Nucl e.ar *
R~gul atory Services Manager..
Richard Hubbard,.
Nathan Schloss..Economist
.
Office of the Attorney General.
. State Lia1son Offi~er
.
Chairman. Illinois Commerce* Cammi ssi on...
-Document Control Desk~LicenSing DOCUMENT NAME:
G:\\EICS\\96391REV.RP
- ,
To receive a copy of this document, Indicate hi the box "C" =Copy w/o attach/encl "E" =Copy w/attach/encl "N":::: No copy
- J. DISTRIBUTION:
PUBLIC IE-01 SECY CA LCa ll an. EDO EJordan. DEDO LChandler. OGC JGoldberg. OGC SCo 11 i ns. NRR RZimmerman. NRR Enforcement Coordinators RI. RII and RIV Resident In~~ectors-Dresden.
HBell. OIG GCaputo, OI DRoss. AEOD *.
OE:ES.
OE::EA (2)
RAO: RII I SLO:RIII *
PAO: RI II OC/LFDCB DRP
.
Docket File
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