IR 05000346/1993015

Insp Rept 50-346/93-15 on 930823-26.No Violations Noted. Major Areas Inspected:Previously Identified Edsfi Findings in Accordance W/Temporary Instruction 2515/111

ML20149D455
Person / Time
Site:	Davis Besse
Issue date:	09/15/1993
From:	Gardner R, Neisler J, Winter R NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION III)
To:
Shared Package
ML20149D447	List: IR 05000346/1993015 ML20149D443
References
50-346-93-15, NUDOCS 9309210043
Download: ML20149D455 (5)

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U. S. NUCLEAR REGULATORY COMMISSION REGION 111 Report No. 50-346/93015(DRS)

Docket No. 50-346 License No. NPF-3 Licensee: Toledo Edison Company

Edison Plaza, 300 Madison Avenue Toledo, OH 43652 Facility Name: Davis-Besse Nuclear Power Station Inspection At: Oak Harbor, OH  ;

Inspection Conducted: August 23 through August 26, 1993 Inspectors: 8 Md & V

/s/93 J. Neisler D-~ t e / l 8W IC Winter W 'l s -S,~ ( 3 D7 e / '-

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Approved By: kb % 3 15 3 i R. fE Gardner, ChleT ~ (<A 4 ~~

Date Plant Systems Section  ;

Inspection Summary Inspection on Auaust 23 - 26. 1993 (Report No. 50-346/93015(DRS)).

Areas Inspected: Announced followup inspection of previously identified EDSFI findings in accordance with Temporary Instruction (TI) 2515/11 ,

Results: The inspection determined that the licensee made adequate progress  !

in resolving EDSFI issues. Eight previously identified findings were closed

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(Paragraph 2.0).

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9309210043 930915

.PDR ADOCK 05000346 G PDR

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DETAILS  ; Principal Persons Contacted

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Toledo Edison Company

• G. Gibbs, Director of Engineering .

• P. Roelant, Plant Engineering  !

• T. LeMay, Maintenance Planning Supervisor

• A. Rabe, Quality Assurance Supervisor ,

• N. Peterson, Regulatory Affairs, NRC Coordinator

• G. Honma, Regulatory _ Affairs, Compliance Supervisor

• M. Leisor, Regulatory Affairs, Senior Engineer

• K. Nicely, Regulatory Affairs

U. S. Nuclear Requlatory Commission (NRC)  !

• K. Walton, Resident Inspector

• Denotes those present during the exit meeting on August 26, 199 '

2.0- Action on Previously Identified Inspection Findinos (Closed) Open Item (346/92007-011: The ELMS-AC calculation did not consider the worst case grid voltage in determining the potential j short circuit current contribution from the offsite source during i a fault and the calculation did not identify the backup service l water / dilution pump as a normally operating loa The inspectors reviewed the revised ELMS-AC computer' based calculation C-EE-015.03-004 for short circuit current '

determinations. The revised calculation uses a worst case voltage -

of 1.05 p.u. to determine the grid contribution to the short circuit curren The 1.05 p.u. is identified as the maximum peak- -

grid voltage in the station design-criteri In addition, the

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inspectors noted that Calculation C-EE-015.03-003 had been revised to show the service water / dilution pump modeled as a normally operating 300 hp motor. The revision did not significantly affect-the findings of the original calculatio This item is considere close Closed) Open Item (346/92007-02): EDG_ load table (DWG E-1043, sheet 1/2) did not include all step 1 loads for a loss of ' coolant accident (LOCA) event followed by a loss of offsite power (LOOP).

The inspectors noted that Drawings E-1042 and E-1043 were revised

- to include required _ all step 1 loads. Additionally, the revision increased step 1 cumulative-load to include manual loads which could be energized. The final total load value was less than the continuous rating of the EDG. This item is considered close .

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c. (Closed) Open Item (346/92007-03A): Several essential 4kV and 480 i volt loads appeared to start outside their programmed design sequence step ;

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The previous method of verifying these load starts used the plant computer which had a resolution of 1 1 second. A more accurate i essential load response time was obtained using a chart recorde This data showed that sequence times were acceptable and within [

their programmed design. This item is considered close d. (Closed) Open item (346/92007-03B): Several essential 480 volt ,

loads were not verified to start during bus energizatio i

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Surveillance test procedure DB-SC-03114 was upgraded by listing procedure step numbers next to the acceptance criteria signoff statement and by the addition of a requirement to add a local 4 recording device to monitor two 480 volt essential bus voltage This data will be trended to identify equipment anomalies and failure This item is considered close t e. (Closed) Open item (346/92007-04A): Minimum battery output voltage (105Vdc) was not adequately supported by calculatio ,

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The inspectors verified that procedure DB-ME-03002, Station Battery and Performance Discharge Test, had been revised and that ,

the results from calculation C-EE-002.01-010 had been used to :

establish minimum acceptance criteria during battery performance '

and service tests. The procedure requires that test data be recorded and compared against the minimum acceptance criteria at .

the end of each profile segment. This item is considered close (Closed) Open item (346/92007-04B): Various components may not '

receive adequate voltage during a design basis scenario (LOCA with ;

loss of AC).  !

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The licensee changed calculation No. C-EE-002.01-010 to revise the minimum voltage acceptance value for MV01060 to a value based on ,

manufacturer's data, to add motors MP371C and MP372C which were '

r 1 included in the original calculation and to justify low voltage during the first minute for these motors. Additionally, .;

the revised calculation gave more thorough justification on the i possible effects of low voltage on the' design basis scenari This item is considered close ;

g. 1 Closed) Open Item (346/92007-05): Fault current protection for -

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some containment electrical penetrations did not comply with commitments identified in USAR, Section 8.3.1.2.24; in that, RG !

1.63, Revision 2, Part C and IEEE 279-1971 single failure criteria

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appear to require both primary and backup fault protection over ,

the entire time-current curv j i

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l This issue pertained to approximately 20 circuits that are i normally energized. These circuits have primary fault protection

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over the entire time-current curve, but the backup fault protection is only for the maximum possible fault current versus '

time condition j The inspectors reviewed the Davis-Besse Safety Evaluation Report, supplement 1, dated April 1977 which concluded that based on NRR's review of the electrical penetrations test results, analysis of l design modifications and final design schematics that the )

electrical penetrations were acceptable. Short circuit tests were conducted to ensure that the penetrations could withstand the i maximum possible fault current-time conditions without loss of l mechanical integrit i

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Penetration configuration consists of a #2 AWG (0.25 inch) pass-through conductor connected to a 7 foot #8 AWG pigtail. Circuits connected to the penetrations utilize #12 AWG conductors. A short 1 circuit condition on the cable system should cause the #12 AWG '

conductor to open, isolating the penetration even with failure of I the primary protection and without the backup protectio ^

l Calculation C-NSA-059.01-012 shows that the #12 AWG wire would clear a 651 amperes fault in approximately 5 cycles (0.087 seconds). This is several times faster than the test values identified in Section 8.3.1.2.29 of the FSAR. The calculated maximum fault current was approximately 3200 ampere Opening of the wire would extend the backup prctection to other than only the maximum fault curren Currents less than the maximum available fault current would be interrupted if the primary protection failed. This item is considered closed, h. LClosed) Open item (346/92007-06): The licensee committed to revise Station Procedure to include the USAR commitment to document battery charger performance following a battery performance discharge test to 105 Vdc.

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Procedure DB-ME-03002, " Station Battery Service and Performance Discharge Test", was revised to record data verifying that the 4 battery charger was capable of recharging the battery within 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> while supplying steady state loads. The test results showed the battery was recharged well within the 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> maximum allowed. This item is considered close i. (Closed) Deviation (346/92007-07_1: Deviation between as-built diesel generator fuel oil storage system and ANSI N195. Section 9.5.4.2 of the Davis-Besse USAR states that the fuel oil storage system meets the requirements of ANSI N195-1976. The deviations were: (1) strainers were not installed in the fill lines to the- i day tanks, and (2) the fuel oil storage tanks were not provided l with high level alarm ]

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The licensee is using a portable fuel oil filter skid in the fuel oil storage tank fill line in lieu of an installed straine Instructions and requirements for use of the filter are documented in Procedure DB-0P-06273, " Diesel Fuel Oil Transfer", revision 00, _

dated June 12, 199 The fuel oil storage tanks do not have high level alarms. The alarms were not included in the original design of the system )

although the 1976 version of the FSAR exceptions to ANSI N195 ,

indicates that the storage tanks have high/ low level alarm l Local high level indication is provided by red indicating lights '

dt the storage are The licensee has initiated Change Notice, UCN 92-061 to include.in  :

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the strainer and high level alarm exceptions in USAR section 9.5.4.2. This item is considered close (Closed) Unresolved item (346/90010-03)(DR.S_}: Design engineering l recommended a battery undervoltage (UV) setpoint of 126 1 Vdc and overvoltage (OV) setpoint of 148+0, -2 Vdc. However, the  ;

licensee's relay setting change notice did not speci.fy a setpoint ,

toleranc The plant assigned a setpoint tolerance of 13 Vdc based on a relay  :

meter accuracy of 12%. As a result, there exists the potential for the station battery Technical Specification to be exceeded .

when Measuring and Test Equipment (MTE) accuracy was considere ;

Additionally Design engineering was not cognizant of the plant's implementation of the setpoint toleranc :

Subsequently, design engineering assigned new-setpoint tolerances to assure even with the additional MTE uncertainty setpoints are within their respective Technical Specification limi The j inspectors verified that the licensee had revised Procedure NG-NE-  :

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0310, "Setpoint Control", to assure that the maintenance planning -

group cognizarre of design engineering's setpoint change ;

Procedure DB-MI-00001, " Control Review and Revision of I & C Data Packages, revision 01, dated March 8,1991 was revised to delineate responsibility of the data package writer and the instrument and control (1 & C) mechanics for assuring that complete and correct information is included in the I & C data' packages. This item is .l considered close ' Exit Interview .j i

The inspectors met with licensee representatives (denoted in Paragraph  !

1.0) at the conclusion of the inspection on August.26,.1993. The f inspectors summarized the scope and findings of the inspection

. activitie The inspectors also discussed the likely informational- !

content of the inspection report with regard to documents or processes <

reviewed by the inspector during the inspection. The licensee did not  !

identify any such document or processes as proprietar ,

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