IR 05000237/1985020
| ML17195A865 | |
| Person / Time | |
|---|---|
| Site: | Dresden  |
| Issue date: | 07/02/1985 |
| From: | Gautam A, Williams C NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION III) |
| To: | |
| Shared Package | |
| ML17195A864 | List: |
| References | |
| 50-237-85-20, NUDOCS 8507090250 | |
| Download: ML17195A865 (6) | |
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l U. S. NUCLEAR REGULATORY COMMISSION
REGION III
Report No. 50-237/85020(DRS)
Docket No. 50-237 Licensee:
Commonwealth Edison Company P. 0. Box 767 Chicago, IL 60690 License No. DPR-19 Facility Name:
Dresden Nuclear Power Station, Unit 2 Inspection At:
Morris, IL May 14, 1985, and Chicago, IL June 4, 1985 Inspection Conducted:
May 14 and June 4, 1985 Inspettor:
A. S. Gautam Approved ~y:
C. C. Williams, Chief Plant Systems Section Inspection Summary 4,e-~-~--r~
. ~~<J:lY LM-'V-Inspection on May 14 and June 4, 1985 (Report No. 50-237/85020.(DRS))
Areas Inspected:
Announced special safety inspection by regional inspector of licensee actions on previous inspection findings regarding the Unit 2, 125 V DC battery modification, identified in Region III Inspection Report No. 50-237/85014(DRS).
The inspection involved a total of 6 inspector-hours onsite and 9 inspector-hours offsite by one NRC inspecto Results:
Of the area inspected, no violations or deviations were identified.
8507090250 850702 PDR.ADOCK 05000237 G
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DETAILS Persons Contacted
- J. Scott, Station Manager
- J. D. Brunner, Assistant Superintendent, Technical Services
- R. S. Deobler, Tech Staff Engineer M. Strait, SNED On-Site Repreientative J. Jurecki, Maintenance & Staff Engineer L. F. Sebby, Master Electrician Sargent & Lundy (S&L)
° F. W. Fischer, Senior Electrical Project Engineer 0 R. H. Sadlowski, Electrical Engineer 0 B. G. Treece, Electrical Engineer 0 T. R. Eisenbart, Electrical Engineer
- Denotes those attending the exit meeting on May 14, 1985.
0 Denotes those attending the exit.meeting on June 4, 198 Action on Previous Inspection Findings (Open) Unresolved Item (237/85014-01).
This item addressed NRC concerns regarding the need.for the licensee to perform a service test to verify that the Unit 2, 125 V DC battery would meet the design requirements of the connected DC load Since the licensee is not committed to IEEE 450-75, which references the requirement for a service test, the inspector reviewed the Dresden.Unit 2, 125V DC load profile and battery loading documented by S&L on a January 22, 1985 submittal. The associated calculation (705600-19-2) pages 181 through 190 was reviewed for evidence that the 125V DC battery could supply the connected DC load The inspector reviewed the 125 V DC battery loadings listed in Tabl~ 8.2.3.4 of the Dresden FSAR Rev. 2, dated June 1984, and the analysis of these loads documented in the S&L load profil The inspector also examined these loads in regard to the sizing of the Unit 2, 125 V DC 60 cell plant batter Questions regarding the battery's loading and sizing were discussed in a June 4, 198~,
meeting with representatives of CECo and S&L at the S&L office in Chicago, where battery sizing was also reviewed against methods described in IEEE 485-198 During review of the Unit.2 battery sizing and loading, the inspector determined that the Station Nuclear Engineering Department (SNED) had recommended in their January 23, 1985, memo to the Dresden Station Manager, that loads indicated with an 1M1 in the load profile listing should be measured to verify actual loading, or that a procedure be instituted to manually shed loads indicated by an 1S 1 in the load profile listing prior to startup of Unit *
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These SNED recommendations for load shedding reflected in part a previous NRC concern at Quad Cities Station, where the licensee was required by a Confirmatory Action Letter from the NRC to implement a procedure requiring load shedding to reduce 125 V DC loads within one half hour of a loss of battery charger As of June 4, 1985, no action h~d been taken by the Dresden Station to document and implement the load shedding procedures recommended by SNED in the load profile analysi Unit 2 had been started up and placed back on line on April 14, 1985, approximately two months before NRC identified this omissio On June 10, 1985, a conference call was held with the Dresden Station Assistant Superintendent, who informed the NRC (C. C. Williams and A. Gautam) that appropriate load shedding procedures were being prepared and would be sent to SNED for toncurr~nce. A copy is to be forwarded to the NRC for revie On June 14, 1985, a copy of procedure DGA-13, Revision 0, "Loss of 125 V DC Battery Chargers With Simultaneous Loss of Auxiliary Electrical Power", was received by the NRC from the licensee for revie The inspector compared the loads to be shed as identified in Tables 1 and 2 of this procedure against those recommended to be shed by SNED in the load profile'.
No discrepancies were foun Based on the above review, th.e procedural aspects of this i tern are considered resolve However, Region III has a continuing concern regarding the lack of timely implementation of the SNED recommendations that the subject procedure be implemented prior to Unit 2 startu Based on the foregoing this item remains ope (Closed) Open Item (237/85014-02):
This item addressed concerns regarding the potential of an inadvertent closing of the 125 V DC Panel 5, Compartment Cl, 600 Amp breaker, resulting in a lo~s of feed to the 125 V DC Turbine Building Main Bus 2A-Concerns were also raised by the NRC regarding a lack of protection of the Unit 1 battery during faults in the 125 V DC cable runs due to the Cl breaker being functionally disconnected from the circui The licensee addressed these concerns by issuing Engineering Change Notice (ECN) No. D-85E-04 dated April 10, 1985, which requires the feed from the 125 V DC distribution panel No. 5 comp Cl to be from the 1bus side 1 of the Compartment Cl breaker.* This in effect allows the 600 amp breaker to provide fault protection for the cable runs to the 125 V DC Turbine Building main bus 2A-l. The 600 amp breaker in compartment Cl is to be normally closed while all other breakers in the 125 V DC panels are to be kept manually open with out of service tags posted in accordance with temporary out of service tagging procedure ZAP 3-5 Rev. 1 The licensee is also considering disconnecting the compartment Cl breaker from the panel 5 bus to prevent problems resulting from inadvertent closing of the 125 V DC Panel 5 breaker Based on the above review this item is closed.
- (Closed) Unresolved item (237/85014-03):
This item addressed concerns regarding the licensee not requiring the ventilation system for the Unit 1, 125 V DC HPCI battery room lC to be safety-relate During the previous inspection, the NRC had requested the licensee to calculate the maximum hydrogen buildup during a loss of ventilation in the Unit 1 125 V DC battery roo During this review the inspector examined S&L calculations documented on a May 13, 1985, submittal from S&L to SNED/CEC These calculations provided the time period for the Dresden Unit 1 HPCI battery room lC to reach a two percent hydrogen concentration, during a loss of exhaust fans, with batteries producing a maximum amount of hydrogen and the battery room temperature risin These calculations determined that it could take 219 hours0.00253 days <br />0.0608 hours <br />3.621032e-4 weeks <br />8.33295e-5 months <br /> for a 2%
hydrogen concentration to build up at 77° F, and 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> for a 2%
hydrogen concentration to build up at 131° Based on these calcu-lations, it appears that the maximum concentration of accumulated hydrogen will remain below the normal industry combustible limits of 3% at 77° 'f for a sufficient time to repair the ventilat.io This item is close (Closed)
Open Item (237/85014-04):
The NRC had raised concerns regarding a lack of instructions in the station traveller WR 042720, Rev. 0, for accomplishing the seismic mounting of the Unit 1 HPCI 125 V DC battery rack During this review, instructions regarding the seismic monunting requirements of the battery racks were reviewed in the traveller and found acceptabl Letters from S&L and GNB Batteries Inc. were reviewed for referenced specifications on battery spacers and the clearance of cells from racks_, these specif-ications were verified to be referented on the travelle Based on the above review, this item is considered close (Closed) Noncompliance (237/85014-05a and b):
This item was identified in part as 235/8504-04a on page 7 (typo), section 3.d(2) of report 50-237/8501 The correct item designation is 237/85014-05 This paragraph corrects this erro This item of noncompliance referred to the lack of instructions or procedures to perform cable splices and installatio The licensee responded to this noncompliance in their May 28, 1985, letter to the NRC, and reported issuing specific work instructions covering cable splicing and installation for this battery modificatio During this review the inspector reviewed these work instructions referenced on the revised traveler and found them to be adequat This item is close (Closed) Unresolved item (237/85014-06):
This item referenced a lack of documented evidence of training of those personnel splicing cables associated with the Unit 2, 125 V battery modificatio The licensee subsequently trained appropriate personnel, including 27 electricians, three foremen and six QC inspectors on cable preparation butt splicing and lugging. Cable samples were used during this trainin This training also included instructions on Raychem heat splicing applications, and is being documented on form OPP 107, 11 CEC0 Training Data Entry
Course Information 11 *
Other personnel will be trained as appropriat Based on the licensee's corrective action, this item is close (Closed) Open Item (237/85014-67):
This item referred to NRC concerns regarding appropriate testing of 5 KV cables 11082 and 11083, and 600 V cables 67660, 67661, 67662, and 6766 The tests to be performed were to demonstrate that these cables would perform satisfactoril These cables are being used in a 125 V DC application, and have protective devices on both end During this review the licensee's test program for the above cables was reviewed for adequacy as documented on station traveller WR #D42720 Rev. 1, Operation Numbers 2, 18, 19, 20, 33, 3 The following tests were to be performed, based on the requirements of IEEE 422-197 (1)
2500 V DC megger test, phase to phase and phase to ground, on the 5 KV cable Minimum acceptable reading 3.75 mega ohm Test performed and accepted May 31, 198 (2)
500 V DC megger test, phase to phase and phase to ground, on the entire spliced 5 KV and 600 V ru Minimum acceptable reading - 1.5 mega oh (3). Continuity testing of all cables by lamping out cables end to en (4) Measurement of splice temperatures during a special battery discharge test No. Ml2-2-85-31, at 123 +/- 10 amps for 3 hour3.472222e-5 days <br />8.333333e-4 hours <br />4.960317e-6 weeks <br />1.1415e-6 months <br /> Based on the observed protection, redundancy and low voltage of these circuits, these tests are considered adequate f.or demonstrating that these cables will perform satisfactoril This item is close (Closed) Noncompliance (237/85014-08):
This item of noncompliance referred to a failure to translate design basis requirements, identified by the licensee'*s March 13, 1985, safety evaluation/design summary into specifications or instructions associated with the battery modifica-tio These instructions required all cables running in the same cable pan as the field cable splices to be placed out of service, as stated in the March 13, 1985, summar This statement was characterized by the NRC as a false statemen The licensee responded to this item in their May 29, 1985, letter to the NRC and in this letter. the licensee corrected the false statement by.eliminating the requirement to place cables associated with the splices out of servic In lieu of this requirement the licensee committed to locating the splices in metal enclosure The NRC did not consider splicing of cables in the previous specific locations of this modification to be a noncompliance; however, the noted as-built configuration did not agree with all of the licensees commitment The use of splice boxes to contain the subject cable splices is a more cbnservative approach and resolves the initial concer The lic~nsee has translated requirements for placing the
splices in a metal enclosure to proper design documents by means of Engineering Change Notice ECN D-85E-02 dated April 2, 198 Based on the above licensee actions this item is close.
Exit Interview The inspector met with the licensee's representatives (denoted under paragraph 1) on May 14 and June 4, 1985, and summarized the scope and findings of the inspectio The licensee acknowledged the informatio The inspector also discussed the likely informational content of the inspection report with regard to documents or processes reviewed by the inspector during the inspectio The licensee did not identify any such documents/processes as proprietar