ML20045A212

LER 93-008-00:on 930505,determined That B Train of SBGT Sys Had Been Inoperable.Caused by Procedure Error.C/As Included Bringing Missed Surveillances Up to Date,Revising Procedures & Counselling personnel.W/930603 Ltr

ML20045A212
Person / Time
Site:	Hatch
Issue date:	06/03/1993
From:	Beckham J, Tipps S GEORGIA POWER CO.
To:	NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
References
HL-3330, LER-93-008-01, LER-93-8-1, NUDOCS 9306090531
Download: ML20045A212 (9)

Text

Georgia Power Company 40 inverness Center Parkway ,

• 1

. Post Ofhce Box 129s

, , Birmingham, Alabama 35201 Telephone 20s 877-7279 l n

J. T. Beckham, Jr. Georgia Power

%ce President Nuclear Hatch Project T* ' MYD t mm , sem June 3, 1993 Docket No. 50-321 HL-3330 005544 U.S. Nuclear Regulatory Commission ATTN: Document Control Desk Washington, D.C. 20555 Edwin I. Hatch Nuclear Plant - Unit 1 Licensee Event Report Procedure Error and Miscommunication Result in Missed Technical Specifications Action Statement Gentlemen:

In accordance with the requirements of 10 CFR 50.73(a)(2)(i), Georgia Power Company is submitting the enclosed Licensee Event Report (LER) concerning a procedure error and miscommunication which resulted in a missed Technical Specifications Action Statement. This event occurred at Plant Hatch - Unit 1.

Sincerely, w -[/ -b J. T. Beckham, Jr.

MCM/cr

Enclosure:

LER 50-321/1993-008 cc: Georaia Power Company Mr. H. L. Sumner, General Manager - Nuclear Plant NORMS j U.S. Nuclear Reaulatory Commission. Washinoton. D.C.

]

Mr. K. Jabbour, Licensing Project Manager - Hatch '

U.S. Nuclear Reaulatory Commission. Reaion II Mr. S. D. Ebneter, Regional Administrator Mr. L. D. Wert, Senior Resident Inspector - Hatch 9306090531 930603 PDR S

ADDCK 05000321 PDR

) M l

PU W i

i

% L ForTn 3co U.5. NJLt. tivi ktutA.Aiel CtM415biUN ArrkUrte GiB NU. 3150-U104 ,

(b89) . EXPIRES: 4/30/92 l LICENSEE EVENT REPORT (LER) l l

rALlilii hAML (1) UUCAti huMots (2) PAM f3)

Plant Edwin 1. Hatch, Unit 1 05000321 1l0FIO

ITLE (4)

Procedure Error and Miscomunication Result in Missed Technical Specifications Action Statement EWENT DATE (5) LER huMBER (6) REFORT DATE (7) OThiR FACILITIES IhWOLvED (8) l MONIN DAY YEAR YEAR SEQ hum REV MONTn DAY YEAR FACILITY hAME5 DOCKET huMBER(5)

Plant Hatch, Unit 2 05000366 05 05 93 93 008 00 06 03 93 05000 OPERATING 0 m (11)

MODE (9) 4 20.402(b) 20.405(c) 50.73(a)(2)(iv) 73.71(b)

POWER -

20.405(a)(1)(1) -

50.36(c)(1) 50.73(a)(2)(v) 73.71(c) ,

LEVEL 000 20.405(a)(1)(ii) 50.36(c)(2) 50.73(a)(2)(vii) OTHER (Specify in l 20.405(a)(1)(iii) T 50.73(a)(2)(1) 50.73(a)(2)(viii)(A) Abstract below) 20.405(a)(1)(iv) -

50.73(a)(2)(ii) -

50.73(a)(2)(viii)(B) l 20.405(a)(1)(v) 50.73(a)(2)(iii) 50.73(a)(2)(x)

LICENSE E CONTACT FOR THIS LER (li) l NAME TELEPM0hE NUMBER 4REA CODE Steven B. Tipps, Manager Nuclear Safety and Compliance Hatch 921 367-7851 l COMPLETE ONE LlhE FOR EACH FAILURF DESCRIBED IN THIS REFORT (13)

CAUSE SYSTEM COMPONENT FAkUFAC- R P0RT CAUSE SYSTEM COMPONENT MANUFAC- R P RT TUR ppDS y X BH MC H260 Yes X EK XFMR B093 Yes suPPLEMEhlAL REFORT EAFECTED (14) MONTH DAY YEAR SUBMISSION

] YES(If yes, complete EXPECTED SUEMISSION DATE)  % h0 DATE (15)

A551RACT (16)

)

I 1

On 5/5/93, at 2000 CDT, Unit 1 was in the Cold Shutdown mode and Unit 2 was in the Run mode at a power level of 1805 CMUT (74.1 percent rated thermal power).

At that time, the Unit 1 Shift Supervisor determined that the Unit 1 "B" train ,

of the Standby Gas Treatment (SBGT) system had been inoperable since 0100 on  ;

5/2/93. On that date, Instrument and Control technicians had found a humidity controller in the SBGT system inoperable. However, licensed shift personnel were not aware that this made the "B" train of the SBGT system inoperable and thus did not initiate a Limiting Condition for Operation at that time.

Concurrently, the emergency power source for the redundant train of the Unit 1 SBGT system was inoperable because of component failure. Since one train of the Unit 1 SBGT system was already inoperable due to the failed humidity controller, this invoked the Unit 2 Technical Specifications requirement that the redundant train be declared inoperable due to the lack of an emergency power source.

However, since the condition was not recognized until 5/5/93, the Action statement requiring Unit 2 to be shutdown within 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> was missed. In addition, Unit 1 entered a condition prohibited by the Technical Specifications when it had less than the required number of operable SBGT system trains in a condition wherein Secondary Containment integrity was required. The root causes of this event were a less than adequate procedure and less than adequate communicacions. The calibration procedure which was in use at the time of the event did not list all the effects of removing the controller from service.

Communications among involved personnel resulted in failure to identify this inadequacy. Corrective actions include revising a procedure and discussing communications with personnel in the departments involved in the event. The first action is completed; the second will be completed by 06/30/93. l i

I

.. - . .--~ .- . . . - - - . . - . . .

l NE Wrm am ul Mdie hiuuhi idNaivi ie rwis uMa I,0 ai ,v-sia.i (6-89) LXPIRES: 4/30/92 LICENSEE EVENT REPORT (LER)

TEXT CONTINUATION FAClllTT NAME (1) DOCKE T nun'BER (2) Lf4 NUMBER (5) FAG [ (3)

V L Aii 5f0 NUM Rfv Plant Edwin I. Hatch, Unit 1 05000321 93 008 00 7 or 8 ILXI PLANT AND SYSTEM IDENTIFICATION General Electric - Boiling Water Reactor Energy Industry Identification System codes are identified in the text as (E11S Code XX)

DESCRIPTION OF EVENT On 5/5/93, at 2000 CDT, Unit I was in the Cold Shutdown mode and Unit 2 was in the Run mode at a power level of 1805 CMWT (74.1 percent rated thermal power).

At that time, the Unit 1 licensed Shift Supervisor initiated a Deficiency Card reporting his discovery that the Unit 1 "B" train of the Standby Cas Treatment (SBGT, E1IS Code BH) system had been inoperable since 0100 on 5/2/93. On 5/2/93, Instrument and Control technicians (16C technicians) were performing calibration procedure 57CP-CAL-041-15, "HONEYWELL MODEL R7088C RELATIVE HUM 1DITY SWITCHES," when they discovered that humidity controller 1T46-R753 was inoperable. This controller is required to be operable in order to energize the relative humidity heaters in the SBGT system when the relative humidity of the air entering the filter train exceeds prescribed limits. The heaters ensure the SBGT system can keep relative humidity in the filter trains below the 70t j assumed in the SBGT system design. With the controller inoperable, the heaters cannot turn on when the heater control switch is in t.he " Auto" position, which is the normal position.

On 5/2/93, when the I6C technicians found the controller inoperable, they submitted a Deficiency Card (DC) reporting the condition to licensed personnel  ;

as required. The calibration procedure in use at the time indicated that i annunciation was the only function affected by this condition, so the DC listed .;

this as the only consequence of the inoperable controller. Thus, on the basis  ;

of information available to him at the time, the licensed Shift Supervisor  !

concluded that no immediate action was required to comply with the Technical Speci fica tions . However, some discussion about whether the procedure was correct took place between licensed personnel, the 16C technicians and the System Engineer. Therefore, the technicians and System Engineer initiated j separate, concurrent reviews of the effect of the inoperable humidity controller on the plant. By approximately 0300 CDT on 5/2/93, both the System Engineer and l

the 16C technicians had completed their separate reviews and determined that the inoperable humidity controller affected the SBGT system heater in addition to annunciation. The 16C technicians discussed this information with the STA and the System Engineer discussed similar information with the SOS. However, because of unclear communications, neither the SOS nor the STA realized that this made the affected SBGT. train inoperable Subsequently, the DC was routinely forwarded for generation of a Maintenance Work Order (MWO) and scheduling of repair. When difficulty arose concerning the availability of spare parts, the MWO was sent to the Engineering Support department with a request for assistance in locating suitable replacement parts.

vd, form aooA U.a. hhAA A:.uaAvu CUhaivh A%ns OMb NU 3130-L154 (6-89) EXPlRES: 4/30/92 LICENSEE EVENT REPORT (LER)

TEXT CONTINUATION i FACILITY NAME (1) DOCKET NUMBER (2) LER NUMBER (5) PAGE (3)

YEAR SEO NUM REV l

Plant Edwin 1. Hatch, Unit 1 05000321 93 008 00 3 0F 8 l Hx1 No further action was taken until 5/5/93 when a supervisor in the Engineering i Support department reviewed the MWO and realized that the condition might make the affected SBGT system train inoperable. After consulting the System Engineer, the supervisor and the System Engineer contacted the licensed SOS and conveyed to him their concerns about the operability of the SBGT system. The SOS agreed that the affected train of the SBGT system had been inoperable since 5/2/93.

Additionally, since the Unit 1 "B" train was inoperable, the otherwise unaffected "A" train of the S3GT system had to be declared inoperable due to its emergency power source being inoperabic. Specifically, the emergency power source for the unaffected "A" train of ;he SEGT system, the Unit 1 "A" Emergency Diesel Generator (EDG, EIIS Code EK), was inoperable at tnat time due to a failed component which was identified following surveillance testing. Per the Unit 2 Technical Specifications section 3.6.6.1, both trains of the Unit 1 SBGT system are required to be operable. Unit 2 Technical Specifications section 3.0.5 requires that when one train of a two train system is inoperable, the redundant train can be considered operable only if the normal and emergency power sources to the redundant train are operable. Therefore, since the Unit 1 l "B" train was inoperable and the emergency power source for the Unit 1 "A" train l was inoperable, the Unit 1 "A" train itself had to be declared inoperable from the perspective of Unit 2 requirements for Unit 1 SBGT system availability.

However, prior to declaring the "B" train of the Unit 1 SBGT system inoperable, there was no need to question the operability of the "A" train under Unit 2 Technical Specifications section 3.0.5. With both Unit 1 SBGT system trains thus inoperable, the Action statement for Unit 2 Technical Specifications section 3.6.6.1 requires that the unit be in the Hot Shutdown condition within 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br />. So, by 2000 CDT on 5/5/93, the appropriate Limiting Condition for Operation was entered on Unit 2 in anticipation of entering the Hot Shutdown condition within the next 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> if the Unit 1 SBGT system trains could not be restored to operable status in the interim.

By 2252 CDT, a qualified replacement part had been located in the warehouse and installed in the humidity controller; the Unit 1 "B" train had been restored to operable status, and the shutdown LCO had been terminated.

Subsequent review of Emergency Diesel Generator operability revealed that the Unit 1 "A" Generator had been inoperable since 1805 CDT on 5/2/93 due to component failure, roughly coinciding with the time when the "B" train of the SBGT system had become inoperable. The EDG was not restored to operable status until 0510 CDT on 05/07/93. Therefore, it was concluded that a shutdown LCO had been exceeded based on the fact that both Unit 1 SBGT system trains were inoperable for greater than 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br />. The Unit 1 "B" train of the SBGT system was inoperabic due to the failure of the humidity controller, and the Unit 1 "A" train was inoperable due to the fact that its emergency power supply was not available. Since this condition was not recognized until the event was discovered on 5/5/93, the requirement to enter the Hot Shutdown mode was not satisfied for Unit 2. In addition, review of the requirements for Secondary

l l

j

% iorm .w A U.a inu t.iw k:.uvuu vo Udhb v4 Ar r un U UMa O x W-Un4 (fe89) LXP!RES 4/30/92 LICENSEE EVENT REPORT (LER)

TEXT CONTINUATION FACILilt NAME (1) DCCKET WMBER ( l.' ) LCR NUMBER (5) PAGE (3) y[AR 5[Q NUM 4[v Plant Edwin 1. Hatch, Unit 1 05000321 93 008 00 4 9f 8 ItxI Containment showed that the SBGT system was required to be operable per Unit 1 Technical Specifications section 3.7.B.1.a because the Unit 1 reactor vessel had been pressurized for the Class 1 system leakage test. Since at least one train of the Unit 1 SBGT system was inoperable during this test, Unit 1 also was in a i condition prohibited by the Technical Specifications, i

l CAUSES OF EVENT I 1

The causes of this event were a less than adequate procedure and less than adequate communications.

Procedure 57CP CAL-041-15 was determined to be less than adequate in that it misled I&C technicians and Control Room personnel concerning the eifects of disabling the humidity controller in the SBCT system. Rather than stating that  :

removing the controller from service would result in the inability of the SBGT system heaters to function in the automatic mode, the procedure stated that only annunciation was affected. Licensed personnel would have known to carry out the required actions had the procedure clearly identified all the effects of removing this component from service.

Less than adequate communications occurred when the SBGT System Engineer and 16C technicians discussed the effects of the inoperable humidity controller with the SOS and STA. The STA did not understand from his conversation with the 16C technicians that the condition rendered the heater inoperable when the control switch was placed in the " Auto" position. The STA relayed his understanding of the conversation with the I&C technicians to the SOS who was consulting the System Engineer. As a result or conversations with the System Engineer, the SOS did not change his initial impression that the operability of the Unit 1 "B" SBGT train was not affected. Specifically, the SOS directed his questioning toward the effect of the component failure on the upcoming SBCT system 18-month surveillance. The System Engineer explained that the 18-month SBGT surveillance would not be impacted because the test is conducted with a local heater control switch positioned to continuously energize the humidity controller (as long as flow exists in the SBGT train). Although the Engineer mentioned the fact that the heater would work only if the control switch were placed in the " Manual" ,

position, this did not prompt the SOS to question his previous conclusion that the operability of the affected filter train was not immediately impacted.

REPORTABILITY ANALYSIS AND SAFETY ASSESSMENT This event is reportable per 10 CFR 50.73 (a)(2)(1) because the plant entered a condition which is prohibited by the Technical Specifications. Specifically, Unit 2 Technical Specifications section 3.6.6.1 requires both trains of the Unit 1 SBCT system to be operable, and section 3.0.5 further requires that when one train of a two train system is inoperable, its redundant system is operable only if the normal and emergency power sources to the redundant system are

% vann.,voA v1 w tannLuuthvo Lu h ub Ate m u vHb hu M G-Oiv4 (tr89) f2HRES: 4/30/92 LICENSEE EVENT REPORT (LER) i TEXT CONTINUATION ]

FACIL!1Y NAME (1) CDCKET NUMBER (2) L[R NUMBER (5) PAGE (3)

YEAR 5to %M RfV l

Plant Edwin I . Hatch, Unit 1 05000321 93 008 00 5 Of 8 IExi operable. Since the Unit 1 "B" train of the SBGT system was inoperable due to a i failed humidity controller and the Unit 1 "A" train was inoperable due to its emergency power supply being inoperaHe, the associated Unit 2 Action statement l should have been entered. This action required Unit 2 to enter the Hot shutdown  !

condition within 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br />. However, since the condition was not recognized at the time, the Action statement was not carried out, and the shutdown LCO was exceeded. In addition, Unit 1 entered a condition prohibited by the Technical Specifications in that the number of operable trains of the SBCT system was less than that required by Unit 1 Technical Specifications section 3.7.B.1.a.

Specifically, when the Unit 1 reactor vessel was pressurized for the Class 1 system leakage test, both trains of the Unit 1 SBGT system were required to be i operable, but were not.

l The Standby Gas Treatment system is designed such that airborne particulates and radioactive iodine which may enter the Secondary Containment during a Design Basis Accident (DBA) will be filtered to acceptable levels and released to the environment at an elevated release point through the Main Stack (EIIS Code VL).

The SBGT system for each of the two reactor units is comprised of two 100 percent capacity filtration trains containing fans, dampers, demisters, relative humidity heaters, High Efficiency Particulate Air (HEPA) filters, and charcoal adsorbers which treat the air and ensure that the atmosphere in the Secondary Containment is maintained at a negative pressure in order to minimize ground level releases. The purpose of the heaters in the SBGT system filter trains is to ensure that the relative humidity in the charcoal adsorbers is maintained below 70 percent to prevent moisture from significantly reducing efficiency of iodine adsorption. Each unit's Technical Specifications require the other unit's SBGT system to be operable. That is, Unit 1 requires the Unit 2 SBGT system to be operable in order to respond to a postulated Loss of Coolant Accident (LOCA) on Unit 1. The Unit 2 SBGT is designed such that it can automatically line up and vent the Unit 1 Secondary Containment by way of the common refueling floor. Similarly, the Unit 2 Technical Specifications require the Unit 1 SBGT system to be operable in order to mitigate the effects of an accident occurring on the common refueling floor or of a LOCA on Unit 2 which could result in drywell head leakage into the common refueling floor.

The Emergency Diesel Generators provide onsite backup a.c. power. There are five EDGs for Plant Hatch, two dedicated to each unit and one " swing" EDG which can be either automatically or manually aligned to supply power to either unit as needed. Should a Loss of Offsite Power (LOSP) event occur, the EDGs automatically start and tie to their respective emergency busses within 12 seconds per Unit 1 Technical Specifications section 4.9.A.2.a. In the event of a LOCA, the swing EDG automatically aligns to supply power to the unit which experienced the LOCA.

In this event, the "B" train of the Unit 1 SBGT system was inoperable because the humidity cont roller which switches on its heater was inoperable and was therefore not capable of maintaining the requisite relative humidity needed for design filtration efficiency. Concurrently, the "A" train of the Unit 1 SBGT

% tonn avoA ui Nuuim *si6hivo Umi35nA A r s t a ut Nu a l 50-0104 (fr83) DPIRES: 4/30/92 LICENSEE EVENT REPORT (LER)

TEXT CONTINUATION FACIL11Y NAME (1) DOCKET NUMBER (2) LER NUMBER ($) PAGE (3)

YiAk 5EQ hum KEV Plant Edwin I. Hatch, Unit 1 05000321 93 008 00 6 Of 8  :

IEXT system was inoperable due to the fact that the EDG which is its emergency power supply was inoperable because of a failed component. Since both filter trains were inoperable at the same time, Unit 2 Technical Specifications section j 3.6.6.1 requires that Unit 2 be in the Hot Shutdown condition within 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br />, i As mentioned previously, this action was not carried out because licensed 1 personnel did not realize that the inoperable humidity controller in the "B" train caused the entire train to be inoperable.

Had a design basis LOCA occurred concurrent with an LOSP on Unit 2 during this event, the two Unit 2 SBGT system filter trains would have started and aligned to the Unit 2 Secondary Contairunent and to the unit-common refueling; floor.

These two trains would be sufficient to maintain these areas at a negative pressure with respect to the environment. Thus, any radioactive material that might possibly leak out of the Unit 2 drywell head into the common refueling floor or into the Unit 2 Secondary Containment would be processed by the SBCT system.

The Unit 1 "B" SEGT system train would start if the radiation levels on the refueling floor were sufficient to trip the Refueling Floor Radiation Monitors (EIIS Code IL). In this case, the train would initiate and align to the Unit 1 Reactor Building and the unit-common refueling floor. If the relative humidity of air entering the train exceeded 70 percent and adversely affected the efficiency of the carbon filter, radioactive iodines would ultimately not be filtered out of the exhaust air. In the event that excessive amounts of radioactive material had passed through the filter, radiation monitor (EIIS Code IL) 1D11-R613, located in the Unit 1 SBGT system exhaust line to the Main Stack, would have alarmed in the Main Control Room. The Annunciator Response Procedure for this alarm, 34AR-601-402-IS, "SBGT/DRWELL AND TORUS RADI ATION J HIGH," requires operators to secure the operating SBGT system train and turn on the system which is not in use. However, the standby "A" train would not be available because its emergency power source was inoperable. Therefore, operators would secure the Unit 1 "B" train and rely upon the Unit 2 SBGT system to maintain negative pressure on Unit 2 Secondary Containment and the common refueling floor. As previously noted, these trains would be sufficient to  ;

maintain a negative pressure in the Unit 2 Secondary Containment and the unit-common refueling floor.

Had a design basis LOCA concurrent with an LOSP occurred on Unit I during this event, the "B" train of the Unit 1 SEGT system would have started as designed and both trains of the Unit 2 SBGT system would have started and automatically aligned to the Unit 1 Secondary Containment and the Unit 2 Secondary  ;

Containment. Since the Unit 1 "A" EDG was out of service, systems powered from this EDG would not have enert;ized, so the Unit 1 "A" train of the SBGT system would not have started. Af ter licensed operations personnel had verified that the three available trains had successfully started, one of the Unit 2 trains would be secured and placed in standby. However, on Unit 1 the inoperable humidity controller on SBGT system train "B" would have prevented the heater from energizing. Moreover, this same controller activates the high humidity

m. ionn 3sA u.5. Moum euuutAw Lu+ii:,5iUN A h vta use ha 3ibO-Uwe (6-89) LXPlRES: 4/30/92 LICENSEE EVENT REPORT (LER)

TEXT CONTINUATION FACILITY NAME (1) DOCKET NUMBER (2) LER NUMBER (5) PAGE (3)

TEAR $[0 hum REV Plant Edwin 1. llatch, Unit 1 05000321 93 008 00 7 0F 8 IEX1 annunciator in the Main Control Room; therefore, Control Room operators would have received no indication of excessive humidity in the train should it have been present. Therefore, the "B" train of the Unit 1 SBGT system could have been functioning at less than full efficiency if relative humidity on the train had exceeded 70%, and the system would have given no indication of anomalous performance. In the event that excessive amounts of radioactive material had passed through the filter, radiation monitor 1D11-K613 mentioned above would have alarmed in the Main Control Room and operators would have secured the l

operating Unit 1 SBGT system train and turned on the standby Unit 2 train and aligned it to the Unit 1 Secondary Containment. Both Unit 2 trains would then i provide sufficient capacity to maintain Unit 1 Secondary Containment at a negative pressure and to process any releases into Secondary Containment that would result from a DBA LOCA.

Based on this analysis, it is concluded that this event hac m adverse impact on nuclear safety. This analysis is applicable to all power levels.

CORRECTIVE ACTIONS

1. The inoperable humidity controller was replaced and the affected train of the SBGT system was returned to service. This action is complete.

2. The failed component in the Unit 1 "A" EDG was replaced; the EDG was successfully functionally tested and returned to service This action is complete.

3. Procedure 57CP-CAL-041-1S has been temporarily revised to correctly address the effects of removing the humidity controller from the SBGT system. This revision will be permanently incorporated into the procedure by 11/30/93.

4. This event will be discussed in departmental meetings with the involved departments. The discussion will emphasize the need for timely and complete communications. This action will be completed by 6/30/93.

ADDITIONAL INFOPJ4ATION l

1. Other Affected Systems: No systems other than those already mentioned in i this report were affected by this event. l l

2. Previous Similar Events: No events have been reported in the past 190 years i in which both trains of redundant safety systems were found to be inoperabic  ;

at the same time Events reported in the past two years in which the plant i changed Technical Specifications applicability states without satisfying all prerequisites for doing so are described in the following LERs:

I 1_- - - - ,

u. :,. uua uus,v.o wumiva

, nn.3 w

& g g a i g -oic4 LICENSEE EVENT REPORT (LER)

TEXT CONTINUATION FACILITV NAME (1) DOCKET NUMBER (2) LER NUMBER (5) PAGE (3)

YEAR 5E0 hum REV Plant Edwin I. Hatch, Unit 1 05000321 93 008 00 8 0F 8 TEXT 50-321/1991-012, dated 07/17/91 50-321/1991-025, dated 11/11/91 50-321/1992-019, dated 08/04/92 50-366/1991-016, dated 06/28/91 50-366/1992-012, dated 08/25/92 50-366/1992-025, dated 12/21/92 Corrective actions for these events included bringing missed surveillances up to date, revising procedures, counseling personnel, reviewing the Technical Specifications surveillance program, and issuing management information clarifying the Technical Specifications. These corrective actions would not have prevented this event because the root causes of the events ere er.tirely different; that is, none of the previous events was brought about by component failure.

3. Failed Equipment Information:

Master Parts List Number: 1T46-R753 Manufacturer: Honeywell Model Number: R7088C Type: Humidity Switch Manufacturer Code: H260 E1IS System Code: BH Reportable to NPRDS: Yes Root Cause Code: X EIIS Component Code: MC Master Parts List Number: 1R43-S001A-T45 Manufacturer: Basler Electrical Company Model Number: BE13616001 ,

Type: Electric Transformer Manufacturer Code: B093 Ells System Code. EK Reportable to NPRDS: Yes Root Cause Code: X EIIS Component Code: XFMR

_.