05000302/LER-1995-001, :on 950124,insp Determined Control Complex Habitability Envelope in Leakage Area Exceeded Requirements That Resulted in Condition Potentially Outside Design Basis. Personnel Made Aware of Importance of He
| ML20081B331 | |
| Person / Time | |
|---|---|
| Site: | Crystal River  |
| Issue date: | 03/07/1995 |
| From: | Frijouf J FLORIDA POWER CORP. |
| To: | |
| Shared Package | |
| ML20081B311 | List: |
| References | |
| LER-95-001, LER-95-1, NUDOCS 9503160135 | |
| Download: ML20081B331 (5) | |
| Event date: | |
|---|---|
| Report date: | |
| Reporting criterion: | 10 CFR 50.73(a)(2)(iv), System Actuation 10 CFR 50.73(a)(2)(v), Loss of Safety Function 10 CFR 50.73(a)(2)(vii), Common Cause Inoperability 10 CFR 50.73(a)(2)(viii)(A) 10 CFR 50.73(a)(2) 10 CFR 50.73(a)(2)(x) 10 CFR 50.73(a)(2)(ii)(B), Unanalyzed Condition |
| 3021995001R00 - NRC Website | |
text
T' NRC FORM 366 U.S. NUCLEAR REGULATORY COMMISSIOld APPROVED BY OMB NO. 3150-0104 15G4 EXPIRES 5/31/95 ESTIMATED BURDEN PER RESPONSE TO COMPLY WITH THIS LibENSEE EVENT REPORT (LER)
$$, "U^Js"REun'STRDEN ES$J 0 T i,N,l "*T%
""S M
AND RECORDS MANAGEMENT BRANCH (MNB8 7714) U.S. NUCLEAR e
REGULATORY COMMISSION, WASH!NGTON, DC 205S5-0001, AND To THE PAPERWORK REDUCTION PROJECT (3150-0104), OrFICE OF (See reverse for required number of digits / characters for each block)
MAMGEMENT AND BUDGET, WASHING rON, DC 20503.
FAClWTY NAME (1)
DOCKET NUMBER {2)
PAGE (3)
CRYSTAL RIVER UNIT 3 05000 302 1 OF 4
" t*)
Inspection Determines Control Complex Habitability Envelope In Leakage Area Exceeds Requirements Resulting in Conditinn Pnrentin11v Ontsido Denien Rnnin EVENT DATE (5)
LER NUMBER (6l REPORT NUMBER (7)
OTHER FACILITIES INVOLVED (B)
MQUENTA WSION F ACIUTY NAME DOGKET NUMBLH MONTH DAY YEAR YEAR MNN DAY YEAR NUMBER NUMBE R N/A 05000 f ACluTY NAME DOCarIT NUM8FR 01 24 95 95 001 00 03 07 95 N/A 05000 OPERATING THIS REPORT IS SUBMITTED PURSUANT TO THE REQUIREMENTS OF 10 CFR O (Check one or more) (11)
MODE (9) 1 20.402(b) 20 405(c) 50.73(a)(2)(iv) 73.71(b) l POWER 20 405(a)(1)(i) 50.36(c)(1)
X 50.73(a)(2)(v) 73 71(c)
L LEVEL (10) 100 20 405(a)(1)(n) 50.36(c)(2) 50.73(a)(2)(vii)
OTHER 20 405(a)(1)(ni) 50 73(a)(2)(i) 50.73(a)(2)(viii)(A)
[P'
'" ^}
20.405(a)(1)Ov) y 50.73(a)(2)(#i) 50.73(a)(2)(vui)(B)
Form 366A) 20.405(a)(1)(v) 50.73(a)(2)ftii) 50.73(a)(2)(x)
LICENSEE CONTACT FOR THIS LER (12)
NAML TELEPHONE NUMBLH pncluae Area Cocos James A. Frijouf, Nuclear Regulatory Specialist (904) 563-4754 COMPLETE ONE LINE FOR EACH COMPONENT FAILURE DESCRIBED IN THIS REPORT (13)
CAUSE
SYSTEM COMPONENT MANUFACTURER
CAUSE
SYSTEM COMPONENT MANUFACTURER O PR SUPPLEMENTAL REPORT EXPECTED (14)
EXPECTED MONTH DAY YEAH YEs SUBMISSION
,o pr yes. compim EXPECTED SUBMISSION DATO X
DATE (15)
ADSTRACT (Limit to 1400 spaces, i e., approximately 15 single-spaced typewritten lines) (16)
On January 24, 1995, Florida Power Corporation's (FPC) Crystal River Unit 3 (CR-
- 3) was in MODE ONE (POWER OPERATION), operating at 100% reactor power and generating 882 megawatts. NRC personnel inspected the CR-3 control complex habitability envelope (HE) doors and determined that a total of over thirty-eight square inches (sq. in.) of in-leakage area existed among the five doors observed, while a total of thirty-two sq. in. of in-leakage area is currently allowed. This may have placed CR-3 outside the design basis and may inhibit the Control Room Emergency Ventilation System from performing its safety function.
1 There was no impact on the health and safety of the public. The cause of this event was personnel error due to a lack of understanding of the requirement to maintain the integrity of the HE. A secondary cause is a procedure deficiency.
The immediate corrective action was to substantially reduce the breach area.
Personnel were made aware of the importance of the HE. A change to the Improved Technical Specifications is under consideration which would specifically address the HE. Several other corrective actions will also be implemented.
i NRC f ORM 306 (5 9R 9503160135 950307 PDR ADDCK 05000302 S
e REQUIRED NUMBER OF DIGITS / CHARACTERS FOR EACH BLOCK BLOCK NUMBER OF I
NUMBER DIGITS / CHARACTERS 1
UP TO 46 FACILITY NAME DOCKET NUMBER 3 IN ADDITION TO 05000 3
VARIES PAGE NUMBER 4
UP TO 76 TITLE 5
EVENT DATE 2 PER BLOCK 7 TOTAL 6
LER NUMBER 3 FOR SEQUENTIAL NUMBER 2 FOR REVISION NUMBER 7
OM DATE 2 PER BL CK UP TO 18 - FACILITY NAME 8
OTHER FACluTIES WOMD 8 TOTAL - DOCKET NUMBER 3 IN ADDITION TO 05000 9
1 OPERATING MODE 10 3
POWER LEVEL Il EQUIREMENTS OF 10 CFR CHECK BOX THAT APPLIES UP TO 50 FOR NAME 12 UCENSEE CONTACT 14 FOR TELEPHONE CAUSE VARIES 2 FOR SYSTEM 13 4 FOR COMPONENT EACH COMPONENT FAILURE l
4 FOR MANUFACTURER NPRDS VARIES i
SUPPLEMENTAL REPORT EXPECTED CHECK BOX THAT APPUES 6
15 EXPECTED SUBMISSION DATE y pER BLOCK i
J
NHC FORM asaA U,*i NUCLEAR KGULATORY COMMISSION APPROVEDf NO. 3150- 0104 t'.J4F:16131196 l
LICENSEE EVENT REPORT (LER) g g g Eg gR g g s g g g g TEXT CONTINUATION ggR,EgAgG,eUggTgg 7,CgD AW "E
rKN CT (
0
%P RW R
OFFICE OF MANAGEMENT AND BUDGET,W4SHINGTON DC 20603.
FACILITY NAME (1)
DOOKET NUMBER (2)
LER NUMDER (8)
PAGE (3)
- SEWENTW,
. HEVSON l
CRYSTAL RIVER UNIT 3 (Ch-3) ol sl ol ol ol sl ol 2 ol5 olol1 olo o l 2 lOFl 0 l 4 mi,, _.
. -.__._,_ -. (m
EVENT DESCRIPTION
On January 24, 1995, Florida Power Corporation's (FPC) Crystal River Unit 3 (CR-3) was in MODE ONE (POWER OPERATION), operating at 100% reactor power and generating 882 megawatts. As part of a routine inspection, NRC personnel were inspecting CR-3 control complex habitability envelope [NA](HE) doors [NA,DR].
The inspection determined that a total of over thirty-eight square inches (sq. in.)
of in-leakage area existed among the five HE doors observed. The CR-3 design basis and supporting documents currently permit a total of thirty-two sq. in. of in-leakage area.
Therefore, this breach of the HE may have placed CR-3 outside the design basis.
The event was reported to the Nuclear Regulatory Commission on January 24, 1995 via the Emergency Notification System per the requirements of 10CFR50.72 and was recorded as Event #28273.
It was observed that door C-508, located between the control complex and the turbine building at the 145 foot elevation, comprised the largest single breach of the HE. The permanent door at this location had been removed for replacement and a temporary plywood enclosure and door were constructed around the opening as required by procedure.
A Breach Permit for the activity at door C-508 had been issued. The controlling procedure, CP-137, Breach Authorization Program, includes a statement under the Limits and Precautions section of the procedure that addresses a maximum in-leakage of 94.7 standard cubic feet per minute (SCFM), but provides no conversion factors to convert to breach area. When constructing this enclosure, FPC personnel left a total breach area of 20 sq. in., as measured by the NRC inspector. Upon notification by NRC personnel, FPC personnel substantially reduced the in-leakage area at the temporary enclosure around door C-508 thereby ensuring the plant to be within its design basis.
No Improved Technical Specification (ITS) exists for the HE, however, this breach may inhibit the Control Room Emergency Ventilation System [NA,AHU](CREVS) from performing its safety function. This LER is submitted to conservatively report a condition outside the design basis of the plant in accordance with 10 CFR 50.73(a)(2)(ii)(B) and for loss of safety function in accordance with 10 CFR 50.73(a)(2)(v).
Based on a Standard Technical Specifications (STS) interpretation in effect at the time, LER 90-007-00 was reported under 10 CFR 50.53(a)(2)(1)(B) as a violation of STS for both trains of the CREVS rendered inoperable by a HE breach. When ITS was developed the STS interpretation was not translated into a specific degraded condition nor explicitly addressed in the Bases.
It was identified as a needed Bases improvement during the final Operations / Licensing review of all such interpretations which were eliminated as part of ITS implementation.
NRC Form 966A (6-89)
cred se6A U.C. NUCLEAR FEOULATOHV OCJMisseON APPROVED OMB NO. 3150-0104 EXPlRES 6131/95 LICENSEE EVENT REPORT (LER) g gT g u g gs,Pgs,e,T g gyg g t
TEXT CONTIND % TION g g g g g su g s g g g egR go "a'usin?!fa""#"naU""eNanT*"%fa%
OFFICE OF MANAGEMENT AND DUDGET, WASHIN TON DC 20503.
FActuTY NAME (1)
DOCKET NUMBER (2)
LIR NUMBER (6)
PAGE (3) stove.w m sewsion YEAR M BER M SER CRYSTAL RIVER UNIT 3 (CP-3) 0l 6l 0l 0l 0l 3l 0l 2 9l5 0l0l1 0l0 0 l 3 lOFl 0 l 4 TEXT M moore spece e segured (Ase addirene!NAC Forse 388A'e (17)
EVENT EVALUATION No redundant barrier was available to perform the safety function. If an accident involving a large radioactive release had occurred during the time that the breach was in place, with worst case meteorological conditions and no mitigating effects, operator radiation doses might have slightly exceeded those calculated in the FSAR.
Similarly, if a large chemical release had occurred during the time that the breach was in place, the chemical concentrations in the control complex atmosphere might have slightly exceeded those calculated in the FSAR.
It is unlikely that either of these events would have resulted in the inability of the operators to perform their functions.
Core damage frequency calculations for S0 tank rupture have 2
shown a core damage frequency of 8.13 X 10'8/ year, which fits into the "non-risk significant" region of the NEI PSA (Nuclear Energy Institute Probabilistic Safety Analysis) Application Guide.
No such accidents occurred; therefore there was no impact on the health and safety of the public. No compensatory measures were taken because the breach area at the enclosure at door C-508 was reduced upon notification from NRC inspectors.
CAUSE
The cause of this event was personnel error due to an inadequate understanding of the requirement to maintain the integrity of the HE.
A secondary cause is a procedure deficiency. The procedural guidance provides SCFM data for HE breaches, which is not readily usable by craft personnel.
Specific HE breach area requirements should be provided in a procedure. The temporary enclosure required for work being conducted on door C-508 was a major contributing factor to this event in that over 50% of the total breach area measured by the NRC inspector was provided by the temporary enclosure.
The remainder of the HE doors were well within the limits, and contributed less than 19 sq. in. to the maximum allowable 32 sq. in.
CORRECTIVE ACTION
Since this event is similar to that of a previously reported event (LER 94-010-00, dated December 23, 1994), one of the corrective actions to prevent recurrence developd for that event is also applicable to this event. Since the current event occurrea prior to implementation of the corrective action for LER 94-010-00, the corrective action was not in place to prevent this event, but when implemented, is expected to assist in preventing future recurrences.
NRC Fonn 366A (6-89)
Feise6A U.G. NUCIIAR FEGUI.ATORY COMMISSION APPROVED OMB NO. 3150-0104 EXPIRES 6/31/95 LICENSEE EVENT REPORT (LER) g T g U M E u"ts"T M E M M TEXT CONTINUATION gngrgggug g gig y AN O E HE T
60 104).
OFFICE OF MANAGEMENT AND BUDGET, WASHINGTON OC 20603.
FACKJTY NAME (1)
DOCKET NUMBER g)
LER NUMDER (6)
PAGE (3) sEQUENTmL REVl86DN EAR NWSM NWBM CRYSTAL RIVER UNIT 3 (CR-3) 0l 5l 0l 0l 0l 3l 0l 2 9l5 0l0l1 0l0 0 l 4 lOFl 0 l 4 TEXT (a mwe amaa m esowed use sesreasi Nac rare seu e (17)
The corrective action stated in LER 94-010-00 and applicable to this event follows:
" Additional training will be conducted for applicable personnel to ensure that the requirements and actions relative to the control complex habitability envelope are understood".
Specific corrective actions for this event include the following:
1.
Upon notification by NRC personnel, FPC personnel substantially reduced the in-leakage area at the temporary enclosure around door C-508 thereby ensuring the plant to be within its design basis.
2.
All Nuclear Operations personnel were made aware of the importance of maintaining the HE.
A letter addressing individual responsibilities relative to maintaining the required integrity of the HE was transmitted to all FPC Nuclear Operations personnel.
3.
Guidance will be provided to FPC maintenance personnel, by FPC engineering personnel, relative to the HE.
This guidance will be l
l incorporated into appropriate inspection planning.
4.
A change to ITS is under consideration for proposal to the NRC. It is expected that this change will specifically address the HE and will include required actions and completion times applicable when the HE l
is breached.
Appropriate surveillance requirements will also be included.
5 A document, to be identified, will include in-leakage area limits.
6.
The HE Analysis will be evaluated to determine the potential to remove conservatism.
7.
Additional corrective action recommendations or actions may be developed as applicable.
PREVIOUS SIMILAR EVENTS
There have been two previous reportable events involving HE breaches. LERs 90-007-00 involved HE door removal and LER 94-010-00 involved blocking open a HE door._ _ _ _ _ _ _ _. _ - _ _ _ _ - - _ _..