IR 05000219/1986037

Special Team Insp Rept 50-219/86-37 on 861117-21.Violation Noted:Changes in safety-related Electrical Power Sys Not Documented Prior to Implementation as Evidenced by Differences Between as-built Drawings & Field Installation

ML20207P921
Person / Time
Site:	Oyster Creek
Issue date:	12/31/1986
From:	Anderson C, Thomas Koshy, Paulitz F, Pullani S NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I)
To:
Shared Package
ML20207P906	List: IR 05000219/1986037 ML20207P905 ML20207P911
References
50-219-86-37, NUDOCS 8701200407
Download: ML20207P921 (28)

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U.S. NUCLEAR REGULATORY COMMISSION

REGION I

Report No. 86-37 Docket No. 50-219 License No. DPR-16 Priority -

Category C Licensee: GPU Nuclear Corporation P. O. Box 388 Forked River, NJ 08731 Facility Name: Oyster Creek Nuclear Generating Station

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Inspection At: Forked River, New Jersey and Parsippany, New Jersey Inspection Conducted: November 17-21, 1986 Inspectors: DU IRrt! /2 - 3/-6(

S. V. P lantriead Reactor Engineer date

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/2-3 /- 66 T. Koslif, Reactor Engineer date

/2-31-8d Ec4 F. PauTitz, tor Engineer date Approved by: DUllaws /2- 3/- 8[

C.J. Ape ief, Plant Systems Section date Inspection Summary: Inspection on November 17-21, 1986 (Report N /86-37)

Areas Inspected: Special announced team inspection of the electric power system including: (1) design features of electric power systems, (2) verification of as-built drawings, (3) plant modifications involving significant changes in the configuration of electric power systems, and (4) review of load studies and analyse Results: Of the four areas inspected, one violation was identified (deficiencies in as-built drawings). Three items remained unresolved at the end of inspection (for details, see sections of this report listed in Attachment 4).

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8701200407 870112 9'

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TABLE OF CONTENTS

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~ Intr' oduction and Background 1 Purpose and Scope 2 . Inspection Method 2 Summary of Inspection Findings 3 Details of Inspection of Electric Power Systems 3 5.1 Design Features of Electric Power Systems 3 5. Summary Description 3 5. General Review of Design Features 4 5.2 Verification of As-Built Drawings 7 5.3 Plant Modifications involving Significant Changes in the Configuration of Electric Power Systems 9 5. Quality Assurance and Administrative Controls 9 5.3.2' Review of Modification Packages 10 5.4 Review of Load Studies and Analyses

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5. Load Stedy by Stone and Webster (1981) 11 5. Electrical Load Interrupting Device Coordination Study (1985) 11 5. Load Study of Diesel Generators and Associated

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Buses (1986) 16 5. New Computer Program for Load Studies 17 5.5 Independent Measurements and Calculations 18 Conclusions 18 Unresolved Items 18 Exit Interview 19 Attachments Simplified Sketch of Electric Power Systems References Documents Reviewed List of Inspection Findings Persons Contacted

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INSPECTION OF ELECTRIC POWER SYSTEMS AT OYSTER CREEK Introduction and Background The electric power systems (onsite and offsite) are important to the safety of a nuclear power plant and are, therefore, required to be designed and maintained accordingly. The safety function of each system (assuming the redundant system is not functioning) shall be to provide sufficient caoacity and capability of electric power for the safe operation of the plant under all operating modes including anticipated operational occurrences and postulated accidents. To achieve this safety function, 10 CFR 50, Appendix A, General Design Criterion 17 - Electric Power Systems, specifies several design requirements for these system The Final Safety Analysis Report (FSAR), Section 8, Electric Power Systems, describes how these design requirements are met. It also specifies the licensee's commitments with respect to the applicable Regulatory Guides (RGs) and industry standards such as the Institute of Electrical and l Electronics Engineers (IEEE). The licensee's electric power systems, as originally designed (i.e., prior to the issuance of the Operating License)

and their subsequent modifications, should comply with these requirements and commitment Many of the older plants, since the issuance of their Operating License, may have made several plant modifications which might involve significant changes in the configuration of their electric power systems. In general, these plants have added many plant systems or upgraded system Such modifications usually involve substantial load growth on the electric power systems. As a result, the electrical power systems may be loaded to its rated capacity, or overloaded in some cases and may also adversely affect the functioning of protective relays and coordination of the interrupting devices. The load growth may also create bus under voltage conditions which may trip out or damage motors, result in unnecessary bus transfers, or cause other operational transients. Therefore, it is quite evident that such plant modifications must be evaluated for these potential problems before they are implemente Other types of significant changes in the configuration which might adversely affect the performance of electric power systems are: a transfer of a large load from one bus to another, replacement of system components such as breakers, fuses, or motors with a new design, and changes in the set point of protective relays or breakers. All such changes must also be properly evaluated for potential problem .

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2. ' Purpose and Scope

'The purpose of u, , inspection.was to ascertain that the-present! configuration

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of:the Oyster Creek offsite and onsite electric power systems _is capable of sustaining and/or switching loads as required to support the safe' operation of

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the plant. _This was accomplished by verification that-the physical configura-tion, including ~ modifications, conforms to the current electrical drawings and that the evaluations of:the configuration -are current and supportive of:the required functioning of the power-systems. The verification was accomplished by detailed review of one electrical divisio Primary emphasis was on the

. safety buses and connected loads, including 4160 VAC, 480 VAC,-125V Vital AC, and 125 VD . Inspection Method

.The general design features of the electric power systems as described in

. FSAR Section 8 and as depicted on electrical single line diagrams were reviewed to ascertain that the system design is capable of performing its intended safety function and that the design meets the applicable require-ments and commitments. A selected sample of as-built drawings (electrical single line diagrams).was~ compared with the field configuration by actual walk-through in the' plant, to identify differences, if any, and their causes (deficiency in design, document control, procurement, installation). The licensee's. Quality Assurance (QA) program and associated administrative controls were reviewed to ascertain that adequate controls exist for the safety related activities associated with the modification of the electrical power systeri A sample of modifications involving significant changes in the configuration of.the electrical power systems was selected'for detailed review. The purpose of the review was to verify that the apprcpriate QA and controls were in-effect and adequate safety evaluations were performed by the licensee to ensure that no unreviewed safety questions (10'CFR 50.59) exis For major-changes in the configuration of the systems which could degrade their safety functions, the licensee is required to perform detailed analyses to verify that the new configuration will perform properly under static and dynamic conditions and the minimum design margins are not exceede In general, these analyses are commonly referred to as load studies which include both static and dynamic aspects. The static part of the study veri-fies that the continuous ratings of the system components under worst loading conditions are not exceeded. The dynamic part of the study verifies that the' capability and capacity of the system components under dynamic conditions (such as faults, starting of large motors, transient under voltage, bus transfer, or other transients in the system) are not exceeded. The system should be capable of recovering from such transients to the extent that it will support safe plant shutdown. The scope of inspection included a review of the above analyses performed by the licensee, to verify that they are technically adequat A summary of the inspection findings is given in Section 4. and the details in Section 5. of this repor ,. - . . .. . - -. -..-. .- . .- - .-

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Summary of Inspection Findings

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< No-significant. deficiencies.were' identified with respect to the capability of the electric power systems to perform their safety functions. As a result of the plant walk-through, an apparent violation involving several

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discrepancies in the as-built drawings (single-line electrical diagrams) .

was identified'in that they differ.from the field installation. The team also

, identified minor discrepancies in the FSAR drawings'of the systems and a deficiency. in .the installation of 125' VDC, Battery C, in that the gap between the cells and the holding framework was excessive for seismic considerations.

n The licensee currently has an' informal mechanism to track the electrical load growth (a data sheet). In response to the team's concern, the licensee promptly initiated a formal administrative control procedure which, after appropriate review, will be issued by March 30, 1987. The licensee had

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several general administrative controls in place for adequately controlling the plant modification process. These were found adequate for the control of the electrical modifications as wel .Since the plant was licensed in-1969, the licensee made significant additions of electrical loads or other changes in the systems configuration. To1 analyze-the effect of these changes, the' licensee conducted several load studies and made several improvements in the systems to mitigate'certain potential'

problems. The problems -involved overloading of load center' transformers, degraded voltage on the emergency buses, and the diesel generator. overload under accident conditions. Cooling fans were added on the load center trans-formers to increase their rating from 2000 to 2300 kVA. Shedding of the non-safety related loads on'the emergency buses under accident conditions will improve the degraded voltage conditions of these buses and inhibit overloading of the diesel The licensee is presently developing a new computer based program to track and analyze the effects of future load growth. The licensee expects the program to be in place within approximately a year; it will significantly

. enhance their in-house capability for such analysi Attachment 4 to this report is a listing of the inspection findings and includes reference sections of this report where the details of these find-ings are discussed. The attachment also includes the items found acceptable by the team, based on the licensee commitment or clarifications of the issue . Details of Inspection of Electric Power Systems 5.1 Design Features of Electric Power Systems 5. Summary Description The following is a summary description of the electric power systems which consists of an offsite power system and onsite power systems (see FSAR Section 8 for detailed description).

A simplified sketch of the system is shown in Attachment :e

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. Offsite Power System The unit output power is normally connected to the Jersey Central Power and Light Company (JCP&L) grid via the 230 kV Oyster Creek substation. Two sources of offsite power are l provided via two separate startup transformers fed from the '

34.5 kV Oyster Creek substation. Power is supplied to the 34.5 kV Oyster Creek substation from the 34.5 kV JCP&L trans-mission system and- the 230 kV Oyster Creek substation. Th kV Oyster Creek substation receives power from the unit itself, and.from the 230 kV JCP&L transmission syste Onsite power Systems The onsite power systems consist of a non-Class 1E system and two redundant Class 1E (Safety related) systems. The onsite power systems consist of an AC power distribution system (4.16kV, 480/277V,120/208V), a vital distribution system (120 AC uninterruptible), and a 125 V DC power distribution syste The normal source for both the non-Class IE and class IE dis-tribution systems is the turbine generator, which feeds the Station Auxiliary Transformer through the generator isolated phare bus. The preferred power supply for the distribution systems during startup, shutdown, abnormal or accident con-diti ns is the Startup Transformers, which are fed from the JCP&L transmission system via the 34.5 kV-Qyster Creek sub-statio Two separate and independent Emergency Diesel Generators are provided as the redundant onsite standby power supplies for safety related equipmen .1.2 General Review of Design Features The following documents were reviewed:

FSAR Section 8, Electric Power System *

Other FSAR Sections in Attachment 3, Section *

Electrical Single Line Diagrams (see Attachment 3, Section 4, for drawing numbers).

The scope of review was to ascertain that:

The systems as designed are capable of performing their intended safety function *

The design meets applicable requirements and commitment .

The general design requirements 'and guidance such as Regulatory Guides and IEEE standards currently applicable for the design of the electrical power systems are listed in Attachment However, these requirements and guidances do not fully apply to the older plants such as Oyster Creek. The applicable requirements and guidances are specifically mentioned in various sections of the FSAR (see Attachment 3, Section 1).

The review was to ascertain that these specific requirements and guidances were complied with. It should be noted that the scope of review was quite general in nature and its extent was restricted to those design features selected for the inspection. Emphasis was on the capacity and capability of present configuration of the systems under various accident modes such as Loss of Offsite Power (LOOP) and Loss of Coolant Accident (LOCA), with or without a Single Failur No unacceptable conditions were identified except as follows (Item a. below). Item b. was found acceptable based on the licensee commitment documented therei Potential seismic interference on Safety Related Motor Control Center 1821 Extension As a part of the modifications for meeting 10 CFR 50, Appendix R requirements, the licensee has added a new free standing section to Motor Control Center 1B21. Due to space limitations, the new section is mounted close to another Unit Substation with a gap less than inche The breakers mounted in the subject Motor Control Center are required to function during and after seismic event An evaluation needs to be performed to assess the adequacy of the existing gap to confirm compliance to the perform-ance requirements. This matter was brought to the attention of the licensee during the inspection. The team was informed that the required analysis has not been don This item will remain unresolved pending completion of the licensee's analysis on the seismic interference of Motor Control Center 1B21 extension and its review by NRC (50-219/86-37-01). Discrepancies in FSAR Drawings During the review of the Final Safety Analysis Report (FSAR) updated revision, the team noted the following '

differences between figures presented and the plant configurations:

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' Figure 8.2-1, One Line Diagram 230-34.5 kV Substation, revision 0, December 198 *

Auxiliary transformer primary voltage is shown as 240 kV. The correct voltage is 24 k *

Startup Transformers primary voltage is shown as 345 kV. The correct voltage,is 34.5 k *

The 230 kV switchyard buses are designated as A& They should be designated as C& *

The 230 kV switchyard bus configuration including the main generator connection to the buses is shown incorrectly. The correct configuration is shown in Figure 8.2-2 of the FSA *

The 34.5 kV switchyard lines are not shown correctl These are shown correctly on Figure 8.2- Figure 8.3-3, Block Diagram - Reactor Protection'and Control System Powe *

The 480 Volt diesel generator shown connected into load center 1A2 and 182 does not exis The licensee committed to initiate a task request to revise the above FSAR drawings. Based'on the commit-ments, the team found this item acceptabl Installation Deficiency In 125 VDC Battery C During the facility walkdown of selected electrical systems, the team observed that the Battery C installation had a free air space between the front of the battery jars and the front stringer of the battery rack. This space was five eight of an inch (5/8"). The licensee provided the team with a letter from the battery manu-facture, Gould (GNB), which stated that this space should be from zero to three eighths inches (0"-3/8"). This space requirement was based upon the seismic testing during the qualification program of a similar batter The licensee committed to reduce this free air space with an approved filler material prior to plant restar This item is unresolved pending correction of the excess-ive air space and review by the NRC (50-219/86-37-02).

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5.2 Verification of As-Built Drawings The as-built drawings (single line diagrams) listed in Attachment 3, Section 4, were verified by comparing the drawings with the field configuration by actual walk-through in the plant. The objective of the verification was to identify the differences, if any, between the as-built drawings and the field configuration. The comparison focused on items of potential safety concern and included the following:

Addition, deletion, or transfer of loads on the buses which affect the system configuratio *

Differences in name plate data (e.g., Horse Power, kW, kVA, Full '

Load Amps) of system component *

Differences in continuous, momentary and interrupting ratings of circuit breakers or fuse *

Characteristics of replacement items which could potentially alter

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the performance of the system (e.g., make, type, model number, and design parameters of circuit breakers, fuses, transformers, relays, etc.).

Setting of protective relay The team identified the following unacceptable conditions:

Discrepancies in As-Built Drawings The following discrepancies were identified: D-3033, DC One line diagram Battery C, Revision . Breakers at position 5, 6, 7, 8, 13, 14, and 15 are indicated by Note 1 on the above drawing as rated for 100 Amp It was verified in the field and in the Gould Specification N , Revision 0, Bill of Materials, Item 4, that these breakers are rated for 225 Amp . The drawing indicates a 600A breaker and 500A fuse at position 10 supplying computer supply inverter. Neither the breaker nor the fuse are installed in the fiel . The 70 Amp fuse at position 14 is shown as located within the 125 VDC distribution center. The team verified that this fuse is not located within the distribution cente . . . .

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y 8 BR-3013, Vital one line diagram, Revision 2 . On instrument panel No. 4 at position 15, the drawing indicated a 3 phase 50 Amp breaker. The field installation had 3 single phase breakers with ratings 20A, 20A and 40A respectivel ~ Instrument panel 4B was depicted in the drawing with a 20A breaker to Panel 10R at position 8,~another 20A breaker to Panel 2F at position 15, and a spare breaker at position 17, but the field installation contained blank spaces at these position . At position 803 on MCC 1A2, a key interlock is shown in the drawing; however, the team determined it was not installed in the fiel BR-3004, Auxiliary one line drawing 480V Motor Control Center (MCC), Revision 2 The team observed that on MCC 1A23 at position E04, the motor for the Augmented Pool Cooling Pump was listed in the drawing as 100 H But, as per the General Electric label, the breaker is rated for only 40 HP. The team was unable to verify the nameplate data of the motor as it was located in a high radiation are The above mentioned discrepancies in the as-built drawings were discussed with the licensee engineering personnel at the site and at the Parsippany office. The Electrical department at both loca-tions conducted an extensive search to identify any Field Change Notices (FCNs), " roll up FCNs," or modifications in progress to explain these anomalies. These drawings were documented as control room drawings as per a memo dated October 28, 1986, from the Manager, Information Management Department, and are required for the day to day operation of the plant.

I The licensee is presently instituting an aggressive program to perform a walk-through verification of all the systems that are required for Safe Shutdown of the plant. This is intended to correct any discrepancies in the drawings. The discrepancies identified under items B. and C. have occurred in spite of the verification program conducted during 1983 and 198 The licensee's verification program involves a walkthrough and a drawing verif' ation of the equipment that are required for safe shutdown of the plant. Some of the loa:s on the safety related buses do not perform an active role in the safe shutdown. The dis-crepancy identified under Item A is of this type and would not have been addressed in the present verification program. This is of concern as the non-safety related loads connected to a safety related bus can significantly influence the availability of the safety related bu . -

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A thorough verification of all:the connected. loads including non-safety loads is needed to assure proper performance of the safety'related buses. The undocumented changes.in the installation

'of electrical components accounted for on drawings D-3033 and BR-3013 do'not conform to the Oyster Creek Operational-Quality Assurance Plan, Section 3.1.1, which states that the changes be documented and approved prior to being implemented. This is a violation ofL10 CFR 50, Appendix.B, Criteria V and VI, as-documented-in the enclosed Notice of Violation-(50-219/86-37-03).

5.3. Plant Modifications Involving Significant Changes'in the Configuration

of Electric Power Systems 5. . Quality Assurance and Administrative' Controls The team re'iewed v the Quality Assurance and Administrative Control documents listed in Attachment 3, Section 3, to ascer-tain that adequate administrative controls, in accordance with the requirements of 10 CFR 50 Appendix B, exist for the safety related activities associated with the modification of the electrical power systems.. The safety related' activities include:

Design and Design Change Control (This includes specifi-cations, drawings, procedures and instructions. . Controls include selection and review for suitability of materials, parts and equipment for'their safety-related' functions and independent design verification).

Procurement Document Control (The regulatory and other requirements to assure adequate quality shall be included ir. these documents).

Document Control (This includes drawings, procedures, and instructions, and changes to these documents).

Control of Purchased Material, Equipment and Services (This includes source evaluation and selection; document-ary evidence of quality; and conformance of the supplied ,

material with the procurement document, etc.).

Post-Modification Testing. (Written test procedures incorporating requirements and acceptance criteria; documentation and evaluation of test results.)

The licensee's QA program and administrative controls were reviewed with emphasis on plant modification activities which could potentially affect the safety functions of the electric power system . .- -

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No unacceptable conditions.were identified except as follows:

Administrative Control for Load Growth Presently, the licensee has an informal program for tracking the future electrical load growth. This is in the form of a-data sheet titled " Electrical Distribution Configuration Data Sheet." In response to the team's. concern for a formal admin-istrative control for this activity, the licensee promptly prepared a draft administrative control procedure while the team was onsite. The licensee also committed that the formal procedure, after appropriate reviews, will be issued by

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March 30, 1987. This is an unresolved item pending completion of the above licensee action and its review by NR (50-219/86-37-04)

5. Review of Modification Packages A sample of modifications involving significant changes in the configuration of electric power systems was selected for detailed review. These are listed in Attachment 3, Section The scope of review included a verification that:

The Quality Assurance and Administrative Controls

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described in Section 5.3.1 above were effectively prac-ticed during the implementation of the modifications.

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Adequate safety evaluations were performed to ensure that no unreviewed safety questions (10 CFR 50.59) exis *

Independent design verifications were performed as require *

Adequate post-modification tests were performed and the test results met the acceptance criteri *

The modifications involving a major change in the config-uration of the electrical power systems were further reviewed in detail to determine the extent of the change and its potential effect on the safety functions of these systems. This also determines the need to perform revised load studies (see Section 5.4 below) to verify that the new configuration will adequately perform its intended safety function The team did not identify any unacceptable condition i

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11-5.4 Review of Load Studies and Analyses The licensee had added numerous plant systems and upgraded the existing systems at Oyster Creek Nuclear Generating Station. These modifications have increased the connected electrical loads on the facility electrical distribution system. To analyze the effect of these increased loads on the performance of the electric power systems, the licensee conducted load studies of various nature and scope in 1981, 1985, and 1986, mostly through outside consultants. The results, recommendations, and licensee actions pertaining to these studies are discussed below (Sections 5.4.1, 5.4.2, and 5.4.3). The licensee is currently developing a computer based program to perform such studies in house (see section 5.4.4).

5. Load Study by Stone and Webster (1981)

A study including the static and dynamic effects of the load growth was conducted in March 1981, by Stone and Webster Engineering Corporation (SWEC). The purpose of the study was to determine the effects of the electrical load increase with regard to electrical distribution system components design ratings. These design ratings include steady state current carrying capacity and electrical fault current carrying capa-city. Also, the electrical system was analyzed to determine the voltage profile during different modes of facility opera-tion. Another purpose of the load study was to determine electrical system and component capacity margins which could be used for additional load growt The study identified that some load center transformers and the standby diesel generators would be overloaded during emergency operation Further, if load was added to parts of the system, the interrupting and momentary ratings of the existing switchgear would be exceeded. Also identified in this study was unsatisfactory voltage conditions within the electrical distribution systems during certain facility oper-ating modes. However, the licensee did not fully agree with certain concerns by SWEC documented in this study (i.e., the overloading of the load center transformers and the diesel generators). To address these concerns, the licensee made a revised study and certain modifications to the systems (see Section 5.4.3 below).

5. Electrical Load Interrupting Device Coodination Study (1985)

A dynamic study of the electrical load interrupting device coordination was conducted in May 1985, based on the latest configuration of the electric power systems. This study, lechnical Data Report (TDR) No. 630, reviewed the interrupting device coordination with respect to protective device settings, maximum fault currents at electrical buses and verified that

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breaker interrupting ratings were not exceeded. Further, an

.undervoltage relay coordination study was conducted to verify that short circuit currents would not trip facility buses on undervoltage before the fault was cleared by overcurrent relays. This study included analysis to provide compliance with 10 CFR 50 Appendix R requirements with respect to breaker coordinatio Two of the major differences between the 1981 SWEC study and TOR 630 are as follows:

The 3350 HP Spare Exciter on bus 1A has been deleted from the load lis *

For a LOCA or concurrent LOOP and LOCA condition, two core spray pumps and two core spray booster pumps are considered per train instead of one each per trai As a result of the TDR 630 study, the licensee has made the following recommendations: .16 kV System Lower the overcurrent relay settings of the 4.16 kV normal and emergency bus overcurrent protection to achieve protection for lower level fault . Add overcurrent alarm monitoring for normal 4.16 kV buses 1A and IB, since coordination requirements preclude lowering the bus overcurrent relay setting to that of the equipment ratin . (a) Revise ground fault relay settings for the 4.16 kV emergency buses 1C and 1 (b) Replace ground fault relays on buses IA and 1B in order to achieve coordination with the revised ground fault relay settings on buses 1C and 1 . In order to reduce the momentary short circuit current at the 4.16 kV buses during the emergency mode (LOCA), add an automatic trip to the Reactor Recirculation Pumps on an emergency signa . The second level undervoltage time delay set-ting must be increased from 10 to 15 seconds to avoid the undervoltage relay tripping before the overcurrent relays have cleared the fault _

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13 j Lower the overcurrent relay high dropout l instantaneous unit setting for the Reactor Feedwater Pump Volt Unit substations l Replace the electro-mechanical trip devices of the MCC feeders with solid state trip units to provide better ;

coordination with the downstream feeder breaker Volt AC and 125 Volt DC Motor Control Centers (MCCs)

Ten thermal magnetic molded case circuit breakers at 10 MCCs, supplying downstream MCCs or distribution panels, could be replaced by breakers with solid state protection devices to improve the coordination with downstream feeder breaker Volt DC Panel D The calculated short circuit current at Panel D exceeds the rating of the panel breaker The 10,000 ampere breakers will be replaced by breakers with an interrupt-ing rating of 15,000 ampere or abov The status for the completion of the above proposed recommen-dations are as follows:

Complete Items: A3(a),A3(b),D Partially Complete Items: B, C, ( 10 CFR 50 Appendix R related portions of Items B and C are complete)

To be Completed during refueling outage 12R The remainder of Items B, C (i.e., non-Appendix R related)

Schedule for Completion Not yet established Items: A.1,A.2,A.4,A.5(a),A.5(b)

The review of the electrical system voltage response in the above study (TDR No. 630) was confined to the coordination between the overcurrent protective relay settings and the degraded grid voltage relay settings during various electrical fault conditions. The voltage profile study for both high

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voltage and low voltage conditions under various facility operating modes or off-site power system variations has not been updated since the SWEC 1981 study. There were unsatis -

factory voltage conditions identified in the earlier stud These potential voltage conditions have been improved for the following reasons:

• Load shedding of non-safety loads

• Voltage tap changers on the Startup Transformers

• Voltage regulators in the Startup Transformers source to maintain voltage within i 2.5%.

No unacceptable conditions were identified. Items a. and b. discussed below were found acceptable, based on the clari-fication provided by the licensee, Implementation of the 1985 Load Study Recommendations As discussed before, the study made several recommenda-tions (numbered as A, B, C, and D) to improve the perform-ance of the system. The licensee stated that the recom-mendations associated with 10 CFR 50, Appendix R (Items 0 and part of Items A, B, and C) were completed during the current refueling outage (11 R) and that the remaining portions of recommendations B and C will be completed during the next refueling outage (12R). The licensee's plan and schedule for implementing the remainder of recommendation A has not been established. The licensee also stated that the partial implemantation of the recom-mendation does not have any adverse safety implications on the performance of the electrical power system. This was further verified by the team review of the nature of the implemented recommendation Based on the above, the item is found acceptable, Comments on the Assumptions used in the 1985 Study The team made certain comments on the following assump-tions used in the study and the expected licensee actions for those assumptions to be realistic:

The deletion of 3350 HP Spare Exciter from the load lis *

The recommended trip of Reactor Recirculation Pumps on accident signal *

Use of emergency buses 1C and ID tie breaker under multiple failure .

't i 15 The licensee does not use the spare exciter. However, sin.e this non-use of the spare exciter will permit lowering the relay settings of the normal and emergency 4.16 kV buses and the spare exciter breaker cubicle could be used for reconnecting a new load, the team was concerned that there was no administrative control over the use of the breaker cubicle. The licensee has agreed to provide this administrative control before lowering the relay setting During a LOCA condition, the available fault current from the startup transformer and motors associated with both the normal and emergency buses would exceed the momentary rating of the 4.16 kV breakers by 3.5%. The licensee proposes to reduce this fault current to 97% of the breaker momentary rating by tripping the Reactor Recircu-lation Pumps during a LOCA condition. These pumps are presently tripped for an Anticipated Transient Without Scram (ATWS) condition. The team had a concern that these -

pumps would be tripped to reduce available short circuit current, a different scenario than ATWS, without a proper safety analysis. The licensee committed to performing a proper safety analysis prior to the modificatio The TDR No. 630 study recommended that the tie breakers relays be set to carry the full bus load, and be coordi-

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nated with the emergency bus incoming breakers, but not with down stream breakers. The bases for this recommen-dation are:

• The bus tie breakers are not permitted to be closed during normal operations unless the mode switch is in-either the shutdown or refueling mod * If a loss of power to a Train A or Train B bus occurs, followed by the loss of a motor or Load Center Unit Substation (USS) on the remaining bus (emergency mode plus single failure), it is permiss-ible to close the tie to only actuate the correspond-ing motor or USS of th2 deenergized bus. The licensee assumed that this limitation on the use of the tie breaker will be enforced by plant operational safeguard The team asked what plant operational safeguards were in place to instruct the operator during an emergency condi-tion plus a single failure to perform the manual load shedding prior to closing the bus tie. The licensee stated that the Engineering Department would provide guidance to the Operation Department, concerning the use of the bus tie breaker for the above conditio .

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Based on the above clarifications, the team found this item acceptabl . Load Study of Diesel Generators and Associated Buses (1986)

A steady state or static type of study of the standby diesel generators and associated buses was conducted in January 1986 by the licensee. This study, C.1302-741-5350-001, identified the electrical loading of the Class IE electrical system during the following modes of facility operations:

Normal operation

Loss of Off-site Power (LOOP)

Loss of coolant Accident (LOCA)

Concurrent LOOP and LOCA The licensee applied a derating to the reactor building load center transformers used in the study. This derating included a 2.5% capacity reduction due to voltage drop during a degraded grid voltage condition and 7.5% capacity reduction due to a 5 degree centigrade increase in-ambient temperature for a 24 hour2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> period. The results of the study identified the following overloading conditions on the load center transformers during a LOCA condition:

460V Load Center USS 1A2: 106% of rated capacity

460V Load Center USS 182: 110.1% of rated capacity During the current refueling outage (11R), to address the over-loading conditions of the load center transformers, the licen-see has installed cooling fans to increase their rated capacity from 2000 kVA to 2300 kVA. The load center transformers' loads with respect to the derated capacity, but with the fans, are as follows:

460V Load Center USS 1A2; 92.9% of rated capacit V Load Center USS 1B2: 95.7% of rated capacit The study also indicated that, during a concurrent LOOP and LOCA condition, the standby diesel generators' (SDGs) load with respect to rated capacity are as follows:

SDG No. 1 is 93.7% of rated capacity

SDG No. 2 is 97.7% of rated capacity The 1981 Load Study indicated that the SDGs were 109% and 120%

of their respective rated capacit The team concludes that the difference between the 1981 and the 1986 load study is due to the present load shedding of non-safety load .

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No unacceptable conditions were identified except as follows:

Dynamic Test to Prove Increased Capacity of Diesel Generators The EMD Model MP45 standby diesel generator unit at Oyster Creek Station had a continuous rating of 2500 kW at 0.8 power factor and a short term (2 hour2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br />) rating of 2750 kW for 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> of operation. In a letter dated June 26, 1985, Electromotive, the manufacturer, indicated that the diesel has a 2000 hour0.0231 days <br />0.556 hours <br />0.00331 weeks <br />7.61e-4 months <br /> rating of 2750 kW at 0.8 power factor. It further states that the diesel has the capacity of producing 2850 kW at 0.8 power factor though it is not warrante The licensee's present load study, Calculation N C.802-741-5350-001, indicates a total load of 2677 kW on diesel generator 2. Though this calculation assumes the worst case scenario (concurrent LOOP and LOCA), it is very likely that the load demand on the generator could be substantially higher than the original rating of 2500 k The present diesel generator load test per Technical Specifi-cations surveillace requirements are conducted at 2750 kW for one hour duration twice a. month. However, such tests do not represent the dynamic loading conditions encountered during the accident scenario. During the inspection, the license was unable to produce any dynamic test results on diesel generators to assure their capability to perform at the new rating (2750 kW) with appropriate margin above the projected loading representative of the accident condition This item will remain open pending NRC receipt and review of licensee records on dynamic test of diesel generators at the increased capacity (50-219/86-37-05).

5.4.4 New Computer Program for Load Studies The licensee is in the process of developing a computer based in-house capability for the analysis of the electric power systems, based on a commercially available program called Distribution Analysis for Power Planning, Evaluations and Reporting (DAPPER). The new program is intended to generate load list (static loading of the buses) and to analyse the system for short circuit and voltage profile considerations when major modifications are performed. The results of the program can be used for evaluating the adequacy of the breaker interrupting capacities and the relay coordination. The licensee is currently in the process of inputing the system data into the program. The licensee expects the new program to be in place within approximately a year. When the new program is in place, the licensee expects to significantly enhance their in-house capability to analyze the system when-ever modifications are performe ,_

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5.5 Independer.t Measurements and Calculations 5. Independent Measurements The team made a number of independent measurements to confirm the accuracy of transformer temperature indicators and measure-ments to identify hot spots in the electric power system This included safety related buses and trar.:. formers. Th infrared thermometer available at NRC Region I office was used for these measurements. The accuracy of the infrared ther-mometer was verified by a contact type digital thermometer, also available at the Region. No hot spots were identifie However, it should be noted that the plant was in shutdown condition, the loads on the buses were minimum, and therefore the existence of hot spots was quite unlikel . Independent Calculations The team performed independent hand calculations to verify the technical adequacy and accuracy of the licensee's calculations associated with their load studies (see Section 5.4). As these calculations are quite involved and mostly performed on a computer, only limited portions of the licensee's calculations were verified by the tea No unacceptable conditions were identifie . Conclusions One violation in the area of document control (discrepancies in as-built drawings) was identified during the inspection. Three items remained unresolved at the end of this inspectio Four items were found acceptable based on the discussion with the license The above findings are listed in Attachment 4 of this report which also includes the reference sections where the details of these findings are discussed in this report. The licensee actions and commitments, including actions required to resolve the unresolved items, are discussed in the reference section Based on the team's review and the status of licensee actions, the issues identified by the load studies have been adequately addressed to the extent that further modifications will provide better reliability of the electric power syste . Unresolved Items Unresolved items are matters for which more information is required in order to ascertain whether they are acceptable, violations, or deviation Three unresolved items are discussed in various sections of this report as listed in Attachment . .

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19 Exit Interview Attachment 5 is the list of persons contacted during the inspection. The inspection team met with the licensee representatives, denoted in Attach-ment 5, at the conclusion of the inspection on November 21, 1986. The team

. leader summarized the scope and findings of the inspection at that tim The team leader and.the licensee discussed the contents of.this inspection report to ascertain that it did not contain any proprietary informatio The' licensee agreed that the-inspection' report may be placed in the Public Document Room witnout prior licensee review for proprietary information

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No written material was provided to the licensee by the tea ,

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ATTACHMENT 2 REFERENCES NRC Requirements (1.1) 10 CFR 50.55a, Codes and Standards (1.2) 10 CFR 50.59, Changes, Test and Experiments (1.3) 10 CFR 50, Appendix A, General Design Criteria for Nuclear Power Plants GDC 2 Design Bases for Protection Against Natural Phenomena GDC 4 Environmental and Missile Design Bases GDC 5 - Sharing of Structures, Systems, and Components GDC 17 Electric Power Systems GDC 18 Inspection and Testing of Electric Power Systems GDC 50 Containment Design Bases (1.4) 10 CFR 50, Appendix B, Quality Assurance Criteria for Nuclear Fower Plants and Fuel Reprocessing Plant . Regulatory Guides (RGs)

(2.1) RG Independence Between Redundant Standby (Onsite) Power Sources and Between Their Distribution Systems (2.2) RG Selection, Design, and Qualification of Diesel-Generator Units Used as Standby (Onsite) Electric Power Systems at Nuclear Power Plants (2.3) RG 1.32 Use of IEEE Std. 308, " Criteria for

Class IE Power Systems for Nuclear L Power Generating Stations"

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Attachment 2 2 (2.4) .RG 1.47 Bypassed and Inoperable Status Indication for Nuclear Power Plant Safety Systems (2.5) RG 1.63 Electric Penetration Assemblies in Containment Structures for Light-Water-Cooled Nuclear Power Plants (2.6) RG 1.75 Physical Independence of Electric Systems (2.7) RG 1.81 Shared Emergency and Shutdown Electric Systems for Multi-Unit Nuclear Power Plants (2.8) RG 1.106 Thermal Overload Protection for Electric Motors on Mator-0perated Valves (2.9) RG 1.108 Periodic Testing of Diesel Generators Used as Onsite Power Systems at Nuclear Power Plants (2.10) RG 1.118 Periodic Testing of Electric Power and Protection System (2.11) RG 1.128 Installation Design and Installation of Large Lead Storage Batteries for Nuclear Power Plants (2.12) RG 1.129 Maintenance, Testing, and Replacement of Large Lead Storage Batteries for Nuclear Power Plants Branch Technical Positions (BTPs)

(3.1) BTP ICSB 4 Requirements on Motor-Operated Valves in the ECCS Accumulator Lines (3.2) BTP ICSB 8 (PSB) Use of Diesel-Generator Sets for Peaking (3.3) BTP ICSB 11 (PSB) Stability of Offsite Power Systems (3.4) BTP ICSB 18 (PSB) Application of the Single Failure Criterion to Manually-Controlled Electrically-Operated Valves

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Attachment 2 3 (3.5) BTP ICSB 21 Guidance for Application of RG 1.47 (3.6) BTP PSB-1 Adequacy of Station Electric Distribution System Voltages (3.7) BTP PSB-2 Criteria for Alarms and Indications Associated with Diesel-Generator Unit Bypassed and Inoperable Status NUREG Reports (4.1) NUREG 0800 Standard Review Plan (4.2) NUREG/CR 0660 Enhancement of Onsite Diesel Generator Reliability (4.3) NUREG/CR 2989 Reliability of Emergency AC Power Systems at Nuclear Power Plants Industry Codes and Standards (5.1) IEEE 387-1984 Standard Criteria for Diesel Generator Units Applied as Standby Power Supplies for Nuclear Power Generating Stations l (5.2) IEEE 308-1980 Standard Criteria for Class IE Power Systems for Nuclear Power Generating Stations (5.3) IEEE 317-1983 Electric Penetration Assemblies in Containment Structures for Nuclear Power Generating Stations (5.4) IEEE 384-1981 Standard Criteria for Independence of Class IE Equipment and Circuits (5.5) IEEE 338-1977 Standard Criteria for Periodic Testing of Nuclear Power Generating Station Safety Systems (5.6) IEEE 484-1981 Installation Design and Installation of Large Lead Storage Batteries for Generating Station and Substations (5.7) IEEE 141-1976 IEEE Recommended Practice for Electric Power Distribution for Industrial Plants l-I L

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Attachment 2 4 (5.8) IEEE 242-1975 Recommended Practice for Protection and Coordination of Industrial and Commercial Power Systems (5.9) ANSI C37.04 Rating Structure for AC High-Voltage Circuit Breakers Rated on a Symmetrical Current Basis-(5.10) ANSI C37.06 Preferred Ratings and Related Required Capabilities for AC High-Voltage Circuit Breakers Rated on a Symmetrical Current Basis (5.11) ANSI C37.09 Test Procedure for AC High-Voltage Circuit Breakers Rated on a Symmetrical Current Basis (5.12) ANSI C57.12.00- IEEE Standard General Requirements for 1973/IEEE 462-1973 Distribution, Power, and Regulating Transformers (5.13) ANSI C37.01-1972/ IEEE Standard Application Guide for AC High IEEE 320-1972 Voltage Circuit Breakers Rated on a Symmetrical Current Basis (5.14) NEMA Standard Guide for Loading 011 Immersed Power Publication, Transformers with 65*C Average Winding TR98-1978 Ri te (5.15) NEMA MG1 Motors and Generators Miscellaneous References (6.1) Standard Handbook for Electrical Engineers,-Eleventh Edition, by D. J. Fink and Beat (6.2) BUSS Publication, AIA File No. 31.d.6, Simple Approach to Short Circuit Calculatio (6.3) GE Publication CM662 - Insulated Cable Conductor Data.

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ATTACHMENT 3 DOCUMENTS REVIEWED Final Safety Analysis Report Sections 1.8 Conformance to NRC Regulatory Guides

'1.10 Systematic Evaluation Summary 3.0 Design of Structures, Components, Equipment and Systems 8.0 Electric Power 15.0 . Accident Analysis 17.2 Quality Assurance During the Operations Phase Technical Specification 4.7 Auxiliary Electrical Power Quality Assurance and Administrative Control Documents 1000-POL-7200-0 Operational Quality Assurance Plan, Revision 0-00 Volume 1 Technical Functions Procedures:

TAP-006 Technical Functions Quality Assurance Record Requirements, Revision 1-00 EMP-001 Technical Functions Work Request / Task Request, Revision 1-01 EMP-016 Plant Configuration Control Lists, Revision 2 EMP-019 Plant Modification Engineered by Plant Engineering, Revision 0-00 Volume 2, Technical Functions Procedures:

EP-004 Specifications, Revision 1-100 EP-006 Calculations, Revision 2-00 EP-009 Design Verification, Revision 2-00 EP-011 Quality Classification List, Revision 1-01 EP-012 Power Plant System Lists, Revision 1-00 EP-020 Installation Specification, Revision 1-01 EP-021 Technical Manuals, Revision 2-00 EP-025 As-Built Crawings, Revision 2-00 EP-0XX Engineering Configuration Program Draft LP-006 Plant Technical Specification / Operating License Change Control, Revision 0-00 LP-009 Safety Reviews, Revision 2-01

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Attachment 3 2 Oyster Creek Nuclear Generating Station Procedures:

337 4160 Volt Electrical System, Revision 18 338 480 Volt Electrical System, Revision 15 636.4.003 Diesel Generator Load Test, Revision 25 Drawings 3001, Main One Line Diagram, Revision 11 3002, Auxiliary One Line Diagram, sheet 1, Revision 20 3003, Auxiliary One Line Diagram, sheet 2, Revision 23 3004, Auxiliary One Line Diagram, sheet 3, Revision 27 3005, Auxiliary One Line Diagram, sheet 4, Revision 20 3028, DC One Line Diagram, Battery A&B, Revision 28 3033, DC One Line Diagram, Battery C, Revision 08 Modification Packages SE NO. 402635-001 Appendix R Modification to Electrical Systems, Safety Evaluation, Revision 3 202-76-1 Recirculation Pump Trip, Revision 4 DRF 03611 Environmental Qualification, July 11, 1985 Studies and Analyses GPUN ET-477 and 522, Load Study, Stone and Webster Engineering Corporation, March 1981 1302-741-5350-001, Calculation, Loading of Diesel Generators and Associated Buses, Burns and Roe Inc./GPU Revision 0, May 2, 1986 TRD No. 630 Electrical Load Interrupting Device Coordination Study, Burns and Roe Inc./GPU, Revision 0, May 31, 1985 Computer Program DAPPER, Distribution Analysis for Power Planning, Evaluation and Reporting, SKM System Analysis Inc.,

Mini /Mirco Version 3.1, Copyright 1982, 1983, 1984 Memorandums and Letters Letter from Electro-Motive Division of General Motors to GPU, dated June 26, 1985, EMD Model MP45 Power Ratin Memorandum from Manager Information Management Center to Distribution, dated October 28, 1986, Control Room Drawing List Revisio Letter from Gould Batteries to GPU, dated March 27, 1985, Cell-Rack Ga Memorandum from Electric Power Manager to Manager BWR Licensing, dated November 19, 1986, FSAR Figure Change ,

ATTACHMENT 4 LIST OF INSPECTION FINDINGS FOR DETAILS, ITEM N DESCRIPTION REFER TO SECTIONS 1. Violations (86-37-03) Discrepancies in As-Built Drawings 2. Unresolved Items (86-37-01) Potential Seismic Interference 5.1. on Safety Related Motor Control Center 1B21 Extension (86-37-02) Installation Deficiency in 125 VDC 5.1. Battery C (86-37-04) Administrative Control for Load 5. Growth (86-37-05) Dynamic Test to Prove Increased 5. Capacity of Diesel Generators 3. Acceptable Items Discrepancies in FSAR Drawings 5.1. . Implementation of the 1985 Load 5. Study Recommendations

- Comments on the Assumptions used 5. in the 1985 Study

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'O ATTACHMENT 5 PERSONS CONTACTED General Public Utilities (GPU)

R. Armstrong, EAD/ Engineer II, QC/EC

• R. Chisholm, Manager, Electrical Power & Inst *D. Croneberger,_ Director, Engineering & Design J. Deblasio, Manager, Support Engineering, Oyster Creek (OC)

E. Donovan, Manager, Design & Drafting S. Fuller, Manager. Operation QA, QC T. Gaffney, Manag. , Electrical /I&C Material, QC D. Grace, Director, Engineering Projects, QC D. Jones, Sr. II Electrical Engineer, QC

• M. Laggart, Manager, BWR Licensing R. Larzo, Supervisor, Spare Parts, QC Lefler, Project Engineer, Site Tech. Function {

D. MacFarlane, Sr. Engineer, Operation, QC R. Pruthi, Electrical Engineer M. Radvansky, Manager, Technical Function, QC H. Robinson, Electrical Engineer

• J. Rogers, Licensing Engineer, QC

• G. Sadauskas, Manager, Electrical Power

• J. Thorpe, Director, Licensing & Regulatory Affairs R. Weltman, Manager, Mechanical Material, QC Burns & Roe (B&R)

K. Bugents, Electrical Engineer A. Lamin, Electrical Engineer U.S. Nuclear Regulatory Commission (NRC)

W. Bateman, Senior Resident Inspector

• S. Ebneter, Director, Division of Reactor Safety, Region I

• Denotes those present at the exit meeting.

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