ML18065A065

LER 95-009-00:on 950728,discovered Lack of Procedural Guidance for Pump Repair Following Fire.Proposed Use of Power Supply Breaker Did Not Adequately Address Effect of Loss of Control Power.Performed Independent Assessment

ML18065A065
Person / Time
Site:	Palisades
Issue date:	09/08/1995
From:	ROBERTS W L CONSUMERS ENERGY CO. (FORMERLY CONSUMERS POWER CO.)
To:
Shared Package
ML18065A064	List: ML18065A062 ML18065A065
References
LER-95-009, LER-95-9, NUDOCS 9509150055
Download: ML18065A065 (5)

Text

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__ NRC Form 386. 19,831. FACILITY NAME.111 *1. *. ' ..... * .. *. . ' .. ".:: .. *-:* LICENSEE EVENT REPORT (LERI . . . * ... , . U.S. N.UCLEAR REGULATORY COMMISSION

• ' *. APPROVED OMB NO. 3160.0104**

.. . EXPIRES:.

8/31/86 DOCKET NUMBER 121 PAGE 131 Palisades Plant 0 I 6

• I 0 I 0 I 0 I 2 I 6 I 6 . 1 I OF. 0 5 *TITLE 141 LACK OF PROCEDURAL GUIDANCE FOR PUMP REPAIR FOLLOWING A FIRE EVENT DATE 16) LER NUMBER (6) ----+--R-,EPl"'"OR.;...*

T_D_AT"'TE-16_1

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__ __,--,1 . I SEQUENTIAL REVISION .*". FACILITY ,NAMES .. MONTH. DAY YEAR YEAR NUMBER . NUMBER MONTH DAY, YEAR N/A.

• 0 1 6 1°1°1°1'1 o I 1 2 I s s s s I s -o I o I s -o I o o I s o I s s I s NtA* 0 I 6 I 0 I 0 I 0* I I THIS REPORT IS SUBMIITED TO THE REQUIREMENTS OF .10 CFR I: (CMck '!"",,,,,_.of rM fallooring}

111 l OPERATING N :i0.402(b)

MODE 181 .. . *, 20.4061cl

,_;... .*' . POWER 20.40611)(1 lhl 60.361cll1l

". L£VEL 0 1

-.. (101 20.406(1)(1

)(ii) . -'. ,.

-....._ 20.40611)(1

)(iii) 60.73(1)(2)(1)

-. 20.40611)(1

)(iv) -x 60.7311)(2)(ii) 1---....._ 20.40611l11JM 60.7311)(2)(iil)

LICENSEE CONTACT FOR THIS LER 1121 NAME

• William L. Roberts, Staff Lic,ensing Engineer 60.73(1l12Jlivl

'. .. 60.7311l12JM

-,* 60.7311)(2)(viil 60.73(1)(2)(viii)(AJ 60.7311l12Hviiil1Bl 60.73(1l12)_(xl . . .. ....._ 73.7.1lbl 7.3.7.'lcl

• ** . OTHER (Specify in Abstr,1ci

'below and in Text, NRC Form 366Al TELEPHONE NUMBER AREA CODE I s1*11s 11sl41-lslsl113 COMPLETE ONE LINE FOR EACH COMPONENT FAILURE DESCRIBED IN THIS REPORT 1131 MANUFAC-REPORTABLE I :*i CAUSE SYSTEM COMPOl\IENT_

TURER TO NPRDS* I I I I . I I I I JI :*:*:*:*:

• • • • • I I . I I . I I I r-**********************

SUPPL.EMENTAL REPORT EXPECTED 114) n YES Uf comp1e'r._

E><PECTED DATE!

SYSTEM COMPONENT I I I I I I I I TURER I I I I I I REPORTABLE I >.: : TO NPRDS I>* ) '::' .. ...........

i> MONTH DAY YEAR .EXPECTED SUBMISSION DATE 116) *I I I -ABSTRACT (Ljmit ID l400 sp11ees, i.e., epproximete/y fifttten 'a;ngle-sp11ee typewritten lineal 118) , . On July 28, 1995 .at 12:35 p.m., with the plant in cold shutdown, it was determined that circuits for the Low Pressure Safety Injection (LPSI) pumps (P-67 A and P-678) were not adequ.ately separated to meet 10 CFR. 50, Appendix R, Section 111.G requirements.

The LPSI pumps are part of the plant shutdown cooling system and are required to go to cold shutdown.

• A circuit for one LPSI pump suction interlock, which may disable that pump due to fire damage, is routed in three fire areas where a single fi(e would result in the loss of both LPSI pumps. *This condition had been previously identified and was thought to have been resolved by determining that manual control of one of the LPSI pumps could be regained by*

and stopping the pump from its , power supply breaker. Our reviews have now determined that manual operation of each pump's power supply breaker requires that the breaker have control power which is also defeated by the pump suction pressure interlock circuit failure. Therefore, the pump cannot be started locally from .. its power breaker without preplanned repairs, and the existing procedures do not address the *repairs needed to restore at least one LPSI pump to operation in order to achieve cold shutdown after a fire in the three affected areas. This was later identified as a condition outside of the plant design basis. Appropriate fire tours were established in the three affected areas. This condition was identified as part. of the Palisades Plant Appendix R Enhancement Program. The Appendix R Enhancement Program process is re-assessing compliance strategies for a fire in each fire area and verifying adequacy of the existing procedural guidance .. 9509150055 950908 PDR ADOCK 05000255 S PDR .*,

• '.-.. *'.' .. .. .

1-------,.--------

.. :,._ **' ! NRC Form*366A (9-83) FACILITY NAME 111 Palisades Plant LICENSEE EVENT REPORT (lERi TEXT* CONTINUATiON

• DOCKET NUMBER 121 YEAR LER NUMBER (3) SEQUENTIAL NUMBER U.S. NUCLEAR REGULATORY COMMISSION . APPROVED OMB NO. 3160-0104

• • ..... . EXPIRES: B/31/86

• REVISION NUMBER PAGE 141 . 0 5 0 0 0 i 6 6 9 5 -0 0 9 -0 0 Q

• 2 OF Q 5 *EVENT DESCRIPTION.::.

On July 28, 1995 at 12:35 p.m., with the plant in cold shutdown, it was determined that . cir'c!Jits .for the Low Pressure Safety Injection (LPSI) pumps (P-67 A and P-678) were not .. adequately separated to meet 10 CFR 50, Appendix R, Secti_on 111.G requirements.*

The _ appropriate fire watches were established

.. No other immediate actions were required as the plant was in cold shutdown.

nearing the end of a refueling O!JtagEf. -. .*

• The LPS,1 pumps are part of the plant shutdown cooling system and are needed to go to cold shutdown.

A circuit for the B LPSI pump suction pressure interlock, which may disable that pump due to fire damage, is routed in three fire areas where; 1) the redundant A LPSI pump is located (Fire Area 10), 2) the redundant A LPSI pump suction pressure interlock circuit *is . located (Fire Area 13),and 3) a power supply cable for the redundant A LPSI pump is located (Fire Area 20). This condition of common fire areas for redundant equipment had been -previously identified and thought to have been resolved by determining that manual control of one of the LPSI pumps could be regained by starting and stopping the pump from its power .supply breaker. * '

• Our reviews have now determined t-hat manual operation of each pump's power supply breaker .requires*

that the breaker have control power which is also defeated by the pump suction pressure .permissive circuit failure. Therefore, the existing procedures do not address repairs needed to restore at least one LPSI pump to op.eration

_in order to achieve cold shutdown after a fire in the three identified areas. This results-in a condition outside of the plant design basis'. This condition was identified as part of the Palisades Plant *Appendix R

Program. The Appendix R Enhancement Program process is re-assessing compliance strategies for a fire in each fir_e area and yerifying adequacy of the existing procedural guidance.

This condition is reportable in accordance with 10 CFR 50. 73(a)(2)(ii)(B) as a condition outside the plant design basis. CAUSE OF THE EVENT . . The proposed use of the power supply breaker. as a local manual operation to provide one train of LPSI for cold shutdown operation did not adequately address the effect of a loss of control power on the breaker function.

The prior Appendix R review was not rigorously performed nor documented well enough to identify the condition described above. .. ,.*.* '

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_ __. . NRC Form 36BA . . . (9-83_) . FACILITY NAME i1l Palisades Plant LICENSEE EVENT REPORT (LERI TEXT CONTINUATION DOCKET NUMBER (2) YEAR LER NUMBER (31 SEQUENTIAL NUMBER U.S. NUCLEAR REGULATORY COMMISSION. .

• APPROVED OMB NO. 3150.-0104

• . EXPIRES: B/31 /85 REVISION NUMBER PAGE (41 o* *s o *o. o 2 5 5 9 5 -o o 9 -o o o 3 oF o 5 ANALYSIS OF THE EVENT . Appendix R requires that eq*uipment needed for hot shutdown be protected so that one train

• remains tree of fire damage for a fire in* any area of. the plant. Fire damage .lirT'lits for * *

• components needed to reach cold shutdown are less* stringent than for hot shutdown -**.

• components

.. Specifically, the fire may damage both trains of equipment needed for cold. shutdown as fang as one train can be repaired or made operable wit_hin 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> using capability.

Generic Letter 86-10, "Implementation of Fire Protection Requirements",.

also requires . that procedures be in place to cover alternative shutdown methods and any repair activities needed based* on the maximum level of fire damage that_ is* expected. . . . ' Since the LPSI pumps are used for cold shutdown only_, both trains could be damaged by a single fire as long as repair procedures and material needed for the repair are maintained onsite and could be completed within 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br />.

• Under the Palisades*

Appendix R Enhancement Program, a comprehensive review is being implemented to document the acceptability of Palisades provisions for safe shutdown in the. event of a fire. During this review it was confirmed that. the LPSI pumps would require* local manual breaker operation for a .fire in the three areas identified due to a lack of fire barrier separation between redundant Circuits for each train. In the three fire areas the A LPSI pump * -could be lost due to; 1) its physical location in the fire area (East Engineered Safeguards Room -Fire Area 10), 2) loss of the pump's control power du*e to a fault in-the *pump suction pressure interlock circuits (590 Corridor Auxiliary Building -Fire Area 13) or, 3) loss of power supply to the* pump (Spent Fuel Pool Equipment Room -Fire Area 20). Concurrently, the remaining B LPS_I pump could also lose the control power from a fire in any one of the three areas due to a fault on the pump suction pressure interlock circuit. The Appendix R Enhancement program review determin.ed that the original solutio.n to this problem was identified as regaining operation.

of one of the LPSI pumps by_ locally operating the pump's power supply breaker. Reviews completed as a result of this discovery determined that the failure of either pump's suction pressure interlock circuit causes a fuse to blow in the breaker control circuitry.

Since local manual actuation of the breaker requires this control circuitry to be energized, the pump cannot be started without preplanned repairs (i.e. the fault circuit isolated. and the fuse

• replaced).

The analysis for post-fire safe shutdown did not recognize that the breakers require control power to be manually closed and therefore, the procedures, as written, do not adequately address actions needed to reach cold shutdown. . . The lack of adequate circuit separation for redundant safe shutdown components coupled with appropriate repair pro.cedures in place, results in the plant being outside the design basis for meeting 10 CFR 50, Appendix R, Section 111.G, as the existing plant operating procedures do not adequately compensate for this condition to allow repair within 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br />. An hourly fire tour was established as a compensatory measure for the three affected fire areas. :* *, . 'l J

• .

• • .,* ....... _;__;_.....;.,.

_____ .....;....:_....;..._

_____ _ NRC Form 388A 19-831 . LICENSEE EVENT REPORT TEXT CONTINUATION FACILITY NAME 111 . DOCKET NUMBER 121 Palisades Plant YEAR LER NUMBER 131 SEQUENTIAL NUMBER ' ... ': ' U.S. NUCLEAR REGULATORY.

COMMISSION APPROVED OMB NO. 3150-010.4 . . EXPIRES: 8/31/86 REVISION NUMBER PAGE 141 0 5 0 0 0 2 5 5 9 5 -0 0 9 -0 0 Q 4 OF Q 5 This GOndition however has existed since initial operation of the plant and documentation of fire watches for this extended period of time in. the affected areas cannot be provided.

Therefore*,

• this condition is being reported per-10 CFR 50. ?3(a)(2)(ii)(B) as a condition outside the design basis during previous plant operation.

Although the situation was identified .on July 28, 199J5, the condition w.as not finally determined to be reportable a formal' evaluation of the * . situatio11 was completed.*

The.condition was determined to be reportable fo'llowing disclosure of the evaluation resLJlts at a* plant management revie_w meeting on August 9,, 1995 .. A report of . this condition is beirig made within 30 days from the nianagement meetiflg. . . .

• SAFETY SIGNIFICANCE Besides functioning as the pumps for low pressure safety injection in the event of a plant LOCA, the LPSI pumps are part of the plant shutdown *cooling system and are needed to bring the plant to cold shutdown.

The post-fire safe shutdown requirements require that except for the. loss of off-site power, no other equipment failures need to be assumed. Therefore,_

the loss of the LPSI pumps is limite_d to that caused by a fire and their function in the safe shutdown analysis is sole_ly to bring the plant to cold shutdown.

Following the theoretical Appendix R fire, the plant would be put into hot shutdown over a period of several hours. After this time had passed the plant would ready the shutdown cooling . system and the LPSI pumps would be required to go to cold shutdown.

Once it was determined

• that the plant could not go to cold shutdown because either of the LPSI pumps were not * ._ .* available; the plant cou.ld be* held at hot shutdown until the pumps could be returned.

to service with no safety implications.

• While the plant was jn hot sh*utdovvn, the plant operations . personnel would have considerable time to diagnose the problem and call in off-site support personnel.

This deviation from the design basis has minimal safety implications because of the plants ability to remain in hot Sh\,Jtdown for an extended period. CORRECTIVE In June 1994 an independent assessment of the Palisades Appendix R Program was performed.

The assessment was initiated by plant management because of concerns over the state of compliance to the requirements of 10 CFR 50, Appendix R. *The overall conclusion of the independent assessment was that the Appendix R documentation was insufficient in certain areas to demonstrate regulatory compliance

.. Analyses were not well documented and in many cases were not being maintained current with changes to the plant. The team further concluded that the Appendix R Program was not being given the priority required to effectively establish and maintain the program in today's regulatory environment.

Numerous weaknesses identified during the assessment were recurring problems from previous NRC and consultant audits. In summary, the compliance status of some aspects of the Appendix R program were not readily verifiable because of a lack of auditable documentation: '. ' .; ; . .. '

. ;., . '.: ... * .... :; NRC Form 366A 19*831 * ... .. _._ . FACILITY NAME 11 I Palisades Plant . . . :* . *. "* * . . LICENSEE EVENT REPORT (LERJ TEXT CONTINUATION DOCKET NUMBER 121 LER NUMBER 131 SEQUENTIAL NUMBER U.S. NUCLEAR REGULATORY COMMISSION

• . APPRO\,IED OMB NO .. 3.160-0104 EXPIRES: 8/3.1 /86 REVISION NUMBER PAGE 141 0 5 0 0 0 2 6 6 9 5 -0 . 0 9 -0 . 0 Q 5 OF Q 5 .! ," '. As: a of the* June 1994 asse*ssment, plans to upgrade the progra*m were accelerated; Additional management attention was also placed on ensuring timely identification and . resolution of Appendix R deficiencies.

The: ongoing Appehdix R Enhancement Program is systematical.ly.

a re-evaluation of . the safe shutdown equipment needed complete circuit* analysis,*

evaluating . compliance for potential fire in each area, and documenting the basis _for the * *. new analysis. -Duri.rig the reviews performed as part of this Appe-ndfx R Enhancement Program this issue was identified.

Currently, the Appendix R Enhancement Program is expected to be completed in mid l996:

• Corrective Action : An .hourly fire tour was either verified to already be in plar;e or one wa*s establist:ied for the three affected fire areas to c<;>mpensate for the lack of adequate separation redundant safe shutdown cJrcuits.

• * * . *.. -* *

• Corrective:

Actions to Avoid Recurrence*

1. . The inability to manually operate the power supply breakers for the LPSI pumps (P-67 A and *. P-67.B) will be resolved or separation

_between the red1:mc;tant circuits will *

• provided.*

2. An h9urly fire tour in the three affected fire areas will be maintaine*d until a permanent resolution is provided for the lack of Appendix R circuit separatiqn.

3. Th.e ongoing Appendix R enhancement program is systematically performing a complete circuit analysis, performing circuit walkdowns and re-evaluating fire zones to the .* *

• earlier Appendix R work. Completion of the Appendix R Enhancement Program will assure that any *additional areas of Appendix R cable routing non-compliance are identified. . . ' . . . ADDITIONAL INFORMATION LER 95-004, Which was recently submitted, covered the discovery that redundant diesel

• generator circuits were not separated per Appendix R requirements.