ML20206K766

Requests Assistance to Determine If Tech Spec Change Necessary Re Util 870312 Failure to Perform 10CFR50.59 Review of Drywell Ventilation Sys Change.Response Requested within 2 Wks to Expedite Potential Enforcement Action

ML20206K766
Person / Time
Site:	LaSalle
Issue date:	04/13/1987
From:	Norelius C NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION III)
To:	Crutchfield D Office of Nuclear Reactor Regulation
References
NUDOCS 8704170076
Download: ML20206K766 (4)

Text

E i g I y

APR 131987

~ MEMORANDUM FOR: D. M. Crutchfield, Director, Division of Reactor Projects -

III/IV/V and Special Projects, NRR FROM: Charles E. Norelius, Director, Division of Reactor Projects, Region III

SUBJECT:

REQUEST FOR ASSISTANCE - FAILURE TO PERFORM 10 CFR 50.59 REVIEW ON DRYWELL VENTILATION SYSTEM CHANGE AT LASALLE UNIT 1 (AITS 7030011787)

The following paragraphs describe an event at LaSalle Unit 1 for which NRR assistance is.being requested to determine if a Technical Specification change was necessary. On March 12, 1987, at 5:30 p.m. (CST), while operating at approximately 56% power, the Unit 1 Reactor Operator noticed a problem with the reactor water upset level, shutdown level, and the drywell pressure.

Investigation into the cause of the problem determined that the "B" drywell fan motor had failed. The backup primary containment breaker tripped and the primary containment breaker did not trip. The control room indication still showed the fan being powered. Once the licensee determined the problem was the fan motor and not the breakers, a shutdown of the unit was commenced at 9:45 p.m. (CST). While shutting down at 1:30 a.m. (CST) on March 13, 1987, the licensee declared an Unusual Event emergency classification required by LaSalle's emergency procedures due to a required Technical Specification shutdown. Technical Specification 3.6.1.7 required a commencement of a shutdown within 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> if the average drywell temperature was greater than 135 degrees F. The licensee was unable to determine the average drywell

. temperature due to the fact that the temperature monitors for average drywell temperature were indicating incorrectly because of improper air flow. The flow from the operating 1A drywell fan was flowing back through the shutdown 18 fan (see attached sketch). The licensee took the conservative approach, and shut the unit down.

The licensee was able to terminate the Unusual Event on March 13, 1987, at 12:10 p.m. (CST) after entering the drywell and closing two dampers on the discharge of the 1B drywell cooler fan. This stopped the reverse flow through the 1B fan ventilation duct work and allowed an accurate reading of the thermocouple on the suction to the 1A drywell cooler fan.

8704170076 870413 3 DR ADOCK 0500 pug

O r

D. M. Crutchfied 2 APR 131987 The inspector reviewed this event and determined that in October 1984, the licensee had a problem with the actuators for the drywell dampers (1VP14YA, IVP14YB, IVP07YA and IVP07YB), and at that time disconnected the actuators and wired the dampers open in accordance with an out-of-service (00S). The fans and dampers were originally designed to operate together, such that with a fan off, the associated isolation dampers would also have been closed.

The 00S changed the design such that with a fan off, the cooling air from the operating fan would circulate back through the shutdown fan ventilation system and _ discharge back into the bottom of the drywell with no force of cool air into the upper parts of the drywell. The temperature monitors for drywell average air temperature are located in the bottom of the drywell near the inlets to both A & B drywell coolers. Thus, the temperature instruments used in determining the average drywell air temperature, required by Technical Specification 3.6.1.7, were no longer valid with one of the fans not operating. The system design was changed from two independent systems with one fan each to one combined system with two fans.

10 CFR 50.59 states licensed facilities may make changes in the facility as described in the Safety Analysis Report without prior commission approval unless the proposed change involves a change in the Technical Specifications or an unreviewed safety question. It requires records of the written safety evaluation, which provides the bases for determining that a change does not involve an unreviewed safety question or a change in the Technical Specifications.

The inspector's review of the event determined that the licensee failed to perform and document a 50.59 review on the change to the facility when the licensee wired open the dampers in the drywell which changed the drywell ventilation system from two independent systems with one fan each into one system with two fans. However, to properly classify the severity level of this type of violation, I need to know from you and your staff if the licensee should have sought a Technical Specification amendment. The consequences of modifying the drywell ventilation system could have resulted in a need for a change to Technical Specification 3.6.1.7 to reflect that with either one or both drywell coolers not operating, the average drywell temperature would no longer be indicated accurately and action to shutdown the unit should begin.

Subsequent to the identification by the inspector of the lack of a 50.59 review for this facility change, the licensee performed a 50.59 evaluation and concluded that a Technical Specification change was still not needed.

W c:..

Y D. M. Crutchfied 3 APR13 BB'l I would appreciate a response within two weeks of issuance of this memorandum as to whether the licensee should have sought a Technical Specification change or not. This is to expedite any potential escalated enforcement action that may be needed as a result of a failure of the licensee to seek a Technical Specification change. This issue has previously been discussed with Mr. A. Bournia of your staff. Should you have any questions on this matter please contact M. A. Ring (FTS 388-5602) or N. Gilles (FTS 388-5263) of my staff.

Charles E. Norelius, Director Division of Reactor Projects

Attachment:

As stated cc w/ attachment:

A. Bournia, NRR Resident Inspector, LaSalle y/5 Ll6 o Rll RIIJ RIII c/(l& pf641 RII[D klA G les/jp Ring Warnick Nore i p 4/s/87 qq/57 WM i)

II fI i , , , i 11

, i , i . +

l

$*= I h ll * (4]

! l:

j j l fjld i.

g

. ^ i l-4 M4 e

l 1 8 ) o[ go i j;a g. ,

! I gl 1 I t a. y[ r bh l$ i i .i '

} Q h{ ft , 11 3 , )YI 1 e;I nll l-l ".1 1-s 2

v 3 7s .I g{,

sI l l I 13 : 1 g i y 3*- !i- i  !

.I I t t

_ m .

I x m i t z r_ . . .. . w==- ;! a

~

\ $  %  %

l- E i j Y. 3 1 h/ .E '

G e

I w

k 5 y

l Q/ t/

hn i V (Ei skd i% .

, , ,, / c u rI,i d/ f" i 3=> k .

\ h:- )_E 3 ?i-?" .

't- / wth >

f 1 $

-l_ w-q,q-- V ii* a w) hiL!GdJ j.

~

m ~l a ,

e

,; b ~

M S, .

.- g- m m-; .4 A

<g tJ s

i f! !-

-~

• • • • .+.  ; ,p aa1 g >

c. . ._ m >>

y^

}w)E jk 4 , .p.

i.

d

_ 1 Y_ .

O. ~

2 qdip 7 __ -

.!:!, N 4 7 rE b #81-_TD. m OPE M

/ s--4 e e., 2 -

i,

_ lill[! d6dh e- tu EC ~!EST A .

j; lidi'*MN N i L hEl!ls@!dk i IjiNIO g diu al1 3 l!!

.n >/W +

rv -

"g,'

!d v h,>g

-N Hi n

. . . q g'o- -

m < t. j O

~3 ub:

.tilm!, a2 ,

6  ;

s -3 I h @ ,

- 4 4 -

1

- *t

• I n I I

(',

sf  !

in f 4v**Pg . ! g i

, l Il