IR 05000309/1987012
| ML20237J835 | |
| Person / Time | |
|---|---|
| Site: | Maine Yankee |
| Issue date: | 08/04/1987 |
| From: | Anderson C, Thomas Koshy, Paulitz F, Pullani S NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I) |
| To: | |
| Shared Package | |
| ML20237J791 | List: |
| References | |
| 50-309-87-12, NUDOCS 8708260335 | |
| Download: ML20237J835 (33) | |
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U.S. NUCLEAR REGULATORY COMMISSION
REGION I
Report N /87-12 Docket N License N DPR-36 Priority -
Category C Licensee: Maine Yankee Atomic Power Company 83 Edison Drive Augusta, Maine 04336 Facility Name: Maine Yankee Nucelar Power Station Inspection At: Wiscasset, Maine and Framingham, Massachusetts Inspection Conducted: June 1-5, 1987 Inspectors: M GM'
b Y'87 S. ulJa - ead Reactor Engineer date lbuNan 8-4-f]
T. Ko yy, J gtog Eng,ineer
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date l h wkl [ C&c< f> 9- 50 ~ff 7 l F. Pa litz, Reactor Engineer '
date Also participating in the inspection and contributing to the report were: R. Cooney, NRC Consultant Approved by:
C . ' b_d/c/nt ndersop(Chief b-I-87 f> date
/y Plant ystems Section Inspection Summary: Inspection on June 1-5, 1987 (Inspection Report No. 50-309/87-12)
Areas Inspected: Special announced team inspection of the electric power systems 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: Two violations were identified in one of the four areas inspecte The violations involved a lack of proper acceptance criteria (setpoints) for overcurrent trip devices for safety related (class 1E) 480 V breakers. Five items remained unresolved at the end of the inspection (for details, see sections of this report listed in Attachment 3).
8'70G260335 070821 PDR ADOCK 05000309 G PDR
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TABLE OF CONTENTS .
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l l Introduction and Background......................................... 1 l Purpose and Scope......... .......................................... 3 l Inspection Method........................... ....................... 3 Summary of Inspection Findings...................................... 4 Details of Inspection of Electric Power Systems................ ... 6 1 5.1 General Review of Design Features.............................. 6
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5.2 Verification of As-Built Drawings.............................. 6 J
, 5.3 Plant Modifications Involving Significant Changes in the....... 9 l Configuration of Electric. Power Systems l 5.3.1 Quality Assurance and Administrative Controls........... 9 5.3.2 Review of Modification Packages......................... 10 5.4 Review of Load Studies and Analyses....... .................... 10 5. Load Studies and Analyses Before Operating License. . . . . . 11 5. Load Studies and Analyses .Af ter Operating License. . . . . . . 13 5. Licensee Program to Track Load Growth and to....... .... 21 Perform Load Studies 5.5 Independent Measurements and Calculations.... .... ............ 22 5.5.1 Independent Measurements................ ............... 22 5.5.2 Independent Calculations................................ 22 Conclusions............. ....................... ................... 22 Unresolved Items. ........ ......................... ............... 23 Exit Interview................. ... .... ...... .................... 23
ATTACHMENTS Simplified Sketch of Electric Power Systems......................... Al-1 Documents Reviewed...... ........ .... ......................... .. A2-1 3, Li s t o f In specti on Fi ndi ng s . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A3-1 Persons Contacted. ..... .................. ........... .......... A4-1 i
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INSPECTION OF MAINE YANKEE ELECTRIC p0WER SYSTEMS Introduction and Background i
The electric power systems (onsite and offsite) are important to'the I safety of a nuclear power plant and shall be designed and maintained accordingly. The safety function of each electric system (assuming the redundant system is not functioning) shall be to provide sufficient capacity 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
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Systems, specifies design requirements concerning system capacity, independence, redundancy, availability, and reliability. Further, General Design Criterion 18 - Inspection and Testing of Electric Power Systems, specifies design requirements concerning provisions for their periodic inspection and testin The Final Safety Analysis Report (FSAR),19ction 8, Electric Power I Systems, describes how these design requirements are me 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 Electronics Engineers (IEEE). The licensee's electric i power systems, as originally designed (i.e. , prior to the issuance of the Operating License) were reviewed by the NRC against these requirements and commitment This review was conducted prior to licensing the facilit Following the issuance of the Operating License, plant modifications can be made which involve significant changes in the configuration of the electric power systems. These modifications may involve substantial load growth of the electric power systems. As a result, lacking adequate I controls, the electrical power systems may be loaded to their rated (
capacity, or overloaded. This may adversely affect the functioning of J protective relays and coordination of the interrupting devices. Load I growth may also create bus undervoltage conditions which may trip out or damage motors, restDting in unnecessary bus transfers, or cause other operational transients. Therefore, plant modifications should be evaluated to assure that their effect does not violate the requirements of General Design Criteria 17 and 18, and FSAR commitments, before the modifications 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 component having different functional characteristics; and changes in the set point of protective relays or breakers. All such changes should be evaluated for potential problem ,
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. 3 Purpose and Scope I
The purpose of this inspection was to ascertain _that the present 1 configuration of the offsite and onsite electric power systems is capable i of sustaining and/or switching loads as required to support the safe i operation of the plant. This was accomplished by verification that the )
i physical configuration, including modifications, conforms to the current l electrical drawings and that the evaluations of the configuration are current and that they support the required functioning of the power system This verification was accomplished by a detailed review of one electrical division. Primary emphasis was on the safety buses and l connected loads, including 480 VAC, 125V Vital AC, and 125 VD . Inspection Method l The general design features of the electric power systems as described in l the FSAR Section 8 and as depicted on electrical single line diagrams were reviewed to ascertain that the current system design is capable of j performing its intended safety function and that the current design meets i the applicable requirements and commitments. A selected sample of as-built drawings (electrical single line diagrams) was compared with the field configuration by the inspectors conducting a 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 system 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 appropriate QA and administrative controls were in effect and that 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 1 static and dynamic conditions and to verify that the minimum design margins are not exceede In general, these analyses are commonly referred to as load studies which include both static and dynamic aspect The static part of the study verifies that the continuous ratings of the system components under worst loading conditions are not exceede The dynamic part of the study verifies that the capability and capacity of the system components under dynamic conditions (such as faults, starting large motors, transient undervoltage, bus transfer, or other transients in the system) are not exceeded. The system should be capable of recovering from such transients so that it will support safe
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plant shutdow The scope of this inspection included a review of the )
above analyses performed by the licensee, to verify that the analyses are j technically adequat '
A summary of the inspection findings is given in Section 4, and the i details of the inspection findings are provided in Section S, of this I repor . S_ummary of Inspection Findings f
As a result of as-built drawing verification, two violations were i identified. The violations involved a lack of proper acceptance criteria (setpoints) for overcurrent trip devices for safety related (Class 1E) .
480 V breakers and discrepancies in as-built drawings (one line diagrams) j in that the setpoints shown on the drawings differ from the field instal- 1 lation. The licensee initiated prompt corrective actions to address the '
concerns identified in the violation Over a number of years since the plant received the original Operating )
Licensee (OL) in 1972, the licensee had made significant additions of electrical loads and other changes in the system configuration. To analyse the effect of these changes, the licensee conducted several load i studies and analyses. These include the studies and analyses performed ]
recently (1985-87) by Stone and Webster (S&W). To address the issues j resulting from the S&W studies, the licensee has initiated several 1 actions. With respect to the following issues which the inspection team l identified as significant, the licensee made certain commitments as 'j discussed below: S&W Study E-3, Cable Ampacity, did not include a static loading calculation of the present configuration of the onsite electric power system under nornal full load condition The licensee has !
committed to complete this part of the study by August ;1, 1987 i (Reference YAEC Memorandum from F. D. Baxter to R. P. Shone, dated l May 11, 1987).
1 S&W Study E-5, Short Circuit Study-Medium Voltage, indicates that the momentery duty of 6.9 kV breakers exceeds their r,omentary rating of 70,000 Ampers by approximately 1.4 percentage and the interrupting duty of the 4.16 kV breakers exceed their rating of 33,200 Amperes by approximately 6.7 percentage under the worst case assumptions (Reference YAEC Memorandum from F.D. Baxter to R.P. Shone, dated March 9, 1987). The licensee committed to study alternative solutions for a long term corrective action to this problem within the next 3 months (i.e., by August 31,1987) and to determine a final solution and report it to NRC within another 3 months (i.e., by ;
November 30,1987). In the interim, the licensee has taken action '
to limit plant operation to those large motor loads shown in Attachment 1 to the March 9, 1987 memorandum, thereby preventing any
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further increase in the interrupting duty of the 4.16kV and 6.9kV breaker Considering the low probability of an electrical fault ,
coincident with the conditions of the worst case assumptions, the j team determined that the above licensee actions are adequat ] A recent S&W study on protective device coordination indicated inadequate coordination between molded case circuit breakers used in the low voltage distribution panels. In YAEC memorandum from F. D. Baxter to R. P. Shone, dated April 17, 1987, the licensee stated that, since coordination between the magnetic elements of molded case circuit breakers is in most cases impossible.to achieve, these short comings are deemed acceptable. However, the team was {
concerned whether such inadequate coordination would diminish the {
availability of electric power supplies to redundant safety related i components to the extent it affects safe shutdown of the plant. To i resolve this issue, the licensee committed to complete a study by I August 31, 1987. As the redundant safety related components are generally powered from separate and independent sources, the t l probability of loosing the redundant components due to inadequate I coordination is small. Based on this, the team determined that the )
above licensee action is adequate in the interi l The licensee had several general administrative controls in place for controlling the plant modification process. They were found general- .
ly adequate for the control of electrical modifications. However, !
they were not specific enough for tracking electrical load growt l The licensee currently has an informal mechanism to track electrical load growth. Although the informal program is currently working without any problem, it is liable to fail ir, the tbsence of a formal administrative control. In response to tne team's conce n, the licensee promptly committed to prepare a formal administrative l control procedure which, af ter appropriate review, will be issued by August 31, 198 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 l analysi . During a review of past capacity tests for Batteries 1 and 3 to j evaluate approach to end of life, YAEC noted that Batteries 2 and 4 1 had not been tested since they were installed 14 years ag I Surveillance testing requirements are specified for only Batteries 1 l and 3. The licensee is planning to prepare a procedure to test '
Batteries 2 and 4 during the 1989 refueling outag Attachment 3 to this report is a listing of the inspection findings and includes reference sections of this report where the details of these findings are discusse _ _ _ _ - - _ - _ _ _ -_
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I 5. Details of Inspection of Electric Power Systems 5.1 General Review of Design Features I
The following documents were reviewed l
Technical Specification FSAR Section 8, Electric Power System Other FSAR Sections listed in Attachment 2, Section Electrical Single Line Diagrams (see Attachment 2, Section 2, for drawing numbers).
The scope of review was to ascertain that:
l The systems as designed are capable of performing their !
intended safety function, j The design meets :policable requirements and commitment The general design requirements and guidance such as Regulatory -
Guides and IEEE standards currently applicable for the design of electrical power systems are listed in NUREG-0800, Standard Review Plan, Revision 2 July 1981, Section 8.1. However, the requirements ;
and guidance do not fully apply to older plants such as Maine Yanke '
The applicable requirements and licensee commitments to the guidance are specifically mentioned in various sections of the FSAR (see Attachment 2, Section 1). This review was to ascertain that, for the current configuration of electric power systems, these specific requirements and commitments are satisfied. It should be noted that the scope of review was general in nature. Its extent was restricted to those design features se'lected for the~ inspection. Emphasis was on the capacity and capability of the current configuration of the systems under various accident modes such as Loss of Offsite Power I (LOOP) and Loss of Coolant Accident (LOCA), with or without a Single Failur No unacceptable conditions were identifie .2 Verification of As-Built Drawings The as-built drawings, (single line diagrams) listed in Attachment 2, Section 2, were verified by the inspectors by comparing the drawings with the field configuration in a plant walk-through. The objective of the verification was to identify thy differences, if any, between the as-built drawings and the field configuration. The comparison focused on items of potentisi safety concern and included ;
the following:
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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 Ampere) of system component Differences in continuous, momentary and interrupting rating of circuit breakers or fuse *
Characteristics of replacement items which could potentially alter the performance of the system (e.g., make, type, model number, and design parameters of circuit breakers, fuses, transformers, relays,etc.).
Setting of protective relays, j The deficiencies identified during the inspection are discussed belo I
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Lack of Proper Setpoints for 480V Breaker Overcurrent Trip Devices l l
As a result of as-built drawing verification, the following deficient ;
conditions were identified:
i Drawing 11550 - FE - 1H, 480V One Line Diagram-Unit Substation, Sheet 1, Revision 1 {
j Field installation of overcurrent devices in positions ISB, 150, ISD on Bus 8 and positions 13B, 13C, 130 on !
Bus 7 were rated 225 Amperes unlike the drawing representation of 250 Ampere . The overcurrent device installed at position 160 on Bus 8 was rated 600 Amperes unlike the drawing representation of 350 Ampere Drawing 1150-FE-1C, One Line Diagram-480V MCC-7A, 8A, and ISB, 1 Revision 2 . Field installation of moulded case breaker in position 2FBR was rated 15 Amperes unlike the drawing representation of 30 Ampere . Field installation of moulded case breaker in position 5 RHR was rated 20 Amperes unlike the drawing representa-tion of 30 Ampere .. .
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The above mentioned discrepancies were discussed with the licensee personnel. During the period of this inspection, the licensee was unable to explain these anomalies. This is a violation of Maine Yankee Operations QA Manual, Revision 3,.Section VI Paragraph A, which requires measures to review and control documents including revisions thereto (87-12-01).
Furthermore, licensee procedure 5-77-3, Inspection and Repair of General Electric AK-2 circuit Breakers, Revision 16, includes instructions for calibrating overcurrent device types EC1 and EC2 on 480 Volt switchgear. However, the procedure did not contain any acceptance values (setpoints) for calibrating these devices. The l team interviewed the electricians who perform this type of work. The licensee practice was to read the nameplate data on the overcurrent
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device and use any of the wide range of values on the manufacturer supplied curves for calibratio These overcurrent devices are required to be adjusted at a specified setpoint to obtain breaker coordination. Lack of calibration to the setpoint as required by the '
design documents (Drawings 1150-E-54-A dated March 29, 1971 and 0108-B-9487 dated October 15,1970) could degrade the breaker coordination and make the electrical system susceptible for disrup-tions. This constitutes a violation of Maine Yankee Operations QA .
Manual, Revision 3,Section XI, Paragraph 4b, which requires all :
departments to be responsible for establishing procedures and l acceptance criteria for safety related activities (87-02-02). j Licensee Engineering management developed a progranatic approach to resolve the above concerns. In response to these concerns, the licensee made the following commitments: Reestablish correct setpoints for overcurrent trip devices on 480V safety related buses 7 and 8. Make modifications if-necessary and recalibrates these device Revise the procedure to contain step by step instructions to perform calibratio This activity is to be completed before power operation following the 1987 refueling outage. It is noted that the unit was in the 1987 refueling outage at the time of this inspectio . Reconcile the breaker rating differences between the electrical one line drawing and field installation on all safety related buses, motor control centers, vital buses and DC buses. This activity is to be completed before power operation following the 1987 refueling outag ... .
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9 Reconcile the breaker rating differences between the electrical !
one line drawing and field installation on all non-safety '
related electrical buses and motor control centers prior to power operation following the 1988 refueling outag The team evaluated the above schedule for corrective actions and found it to be acceptabl .3 Plant Modifications Involving Significant Changes in' the Configuration of Electric Power Systems i
5. Quality Assurance and Administrative Controls The team reviewed 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 i related activities associated with the modification of the '
electrical power system The safety related activities ;
include:
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Design and Design Change Control (This' includes specifica-tions, 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 requirements and other requirements to assure adequate quality shall be included in these documents).
Document Control (This includes drawings, procedures, and instructions, and changes to these documents).
J Control of Purchased Material, Equipment and Services (This includes source evaluation and selection; documentary evidence of quality; and conformance of the supplied
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material with the procurement document, etc.).
Post-Modification Testing (Written test procedures incorporating requirements and acceptance criteria; documentation and evaluation of test results). l The licensee's QA program and administrative controls were reviewed with an emphasis on plant modification activities which could potentially affect the safety functions of the electric power system No unacceptable conditions were identifie i u_ ___,____m_.mm___ _ - - - - - - - - - -- -
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5. Review of Modification Packages j l
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 review focussed mainly on the change control aspect of the modifications. The scope of review included a verification l
that:
The Quality. Assurance and Administrative Controls described in Section 5.3.1 above were effectivel !
practiced during the implementation of the modification Adequate safety evaluations were performed to ensure that no unreviewed safety question (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 configuration of the electrical power systems were further reviewed in detail to determine the extent of the change
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system This also determines the need to perform revised load studies (see Section 5.4 below) to verify that the new configuration 1 will adequately perform its intended safety function No unacceptable conditions were identified.
l 5.4 Review of Load Studies and Analyses The team reviewed the licensee's load studies and analyses performed before and after the Operating License was issued. This included l load schedules, short circuit studies, relay coordination studies, and degraded grid voltage studies. The team also reviewed the !
licensee's program to track electrical load growth and perform load studies. The scope of the review was to ascertain that:
Static loading on the buses is within the rated capacity of the buses and associated transformers, cables, circuit breakers, and diesel generators (for safety related buses) under normal and accident condition Bus transfer schemes, under loss of power, degraded grid or under-voltage conditions, will function properl _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _
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Switching of large loads such as pumps will not result in undesirable bus voltages or other unstable system condition The system components such as circuit breakers have an adequate momentary and interrupting rating to safely clear the worst possible faul The circuit breakers, fuses, and protective relays are properly coordinated to selectively 1solate only the faulted portion of l
the system and to provide continuity of the power suppl J l
The licensee has adequate administrative controls for tracking '
load growth in a systematic manner and a program to perform load studies when necessar !
5. Load Studies and Analyses before Operating License- s l
The initial power station electrical load studies and analyses i were made by the Architect Engineer (AE), Stone and Webster {
Engineering Corporation, during the period of June 1967 to j July 1972. These studies and calculations were used to i determine the electrical distribution system and components )
performa,nce requirements. These performance requirements were '
then translated to procurement specification The studies and calculations included the following:
Load flow study identified all AC electrical loads on the power station electrical distribution systems. The loads were determined for all plant operating condition Load flow study was used to determine the continuous current rating of the electrical system and component Load flow study was also used to select. transformer impedance to limit the postulated transient electrical fault current to within the system and components design limit Static voltage study was made using the load flow and system impedances to assure that the electrical loads remained within their design limit for selected electrical grid voltage variation under all plant operating condition I i
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Electrical distribution system protection coordinations studies were made to assure selective breaker tripping during an electrical system fault condition. This selective tripping assured isolation of the fault and minimized the effect upon the remainder of the electrical syste Similar DC load studies were made'to determine the battery capacities and to design the DC electrical distribution system for the identified loads. The DC electrical fault study was also made to assure that the postulated transient electrical fault current was limited to less than the components design limit The above calculations and studies were reviewed by the tea l The team also observed the transformer name plate impedances, voltage tap settings and switchgear name plate and interrupting fault current rating The team findings are as follows:
The calculations and studies were prepared in accordance with established industry standards. These standards were those existing at the time the calculations and studies were prepare The transformer impedances that were usod in the short circuit calculation were those associated with the trans-former hiah voltage side mid tap (3) position. This position corresponds to the nominal voltage rating such as 345 kV, 115 kV, et The bus duct, switchgear bus, and cable impedances for the electrical distribution systems were not used in the short circuit calculatio This conservatively increased the available postulated fault current in various parts of the electrical system. This conservative value was used to assure that the fault currents were less than the equipment l rating I (
The cable ampacity for motor cables was selected using j 1.15% of the motor full load current prior to any further increase due to raceway derating. The cable ampacity for 480 Volt load center feeders to motor control centers was :
selected using the running loads, not the connected load I
No deficiencies were noted by the tea l i
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5. Load Studies and Analyses After Operating License Voltage Study As a result of a degraded grid voltage condition at Mill-stone Nuclear Power Station Unit 2 in June 1976, the NRC staff, by a Generic Letter dated June 3,1977, requested Maine Yankee Atomic Power Company to address this concer In this letter, the staff requested the licensee to analyze the Class 1E system to determine the grid voltage at which damage could occur when the equipment is operated below the qualified operating voltage. Yankee Atomic Electric-Company (YAEC) performed a voltage study, titled " Auxiliary Power System Voltage Study for Maine Yankee Atomic Power Station" dated February 28, 1980. This study was submitted to the NRC Office of Nuclear Reactor Regulation (NRR) for review. NRR reviewed the licensee submittal and issued a Safety Evaluation to the licensee by letter dated 1 November 12, 1982. As a result of this, the licensee made 1 a design change providing a second level degraded grid ]
protection but which required coincident undervoltage and j a safety injection signal (SIS). The coincident signal a will transfer the Class 1E system from the degraded grid I (offsite source) to the emergency diesel generators (onsite i standby source) only under accident conditions and there-fore avoid unncessary isolation of the offsite sourc The licensee was also to develop an abnormal operating procedure to protect the Class 1E system from a degraded l grid voltage condition without a coincident SI To meet this commitment, the licensee, by letter January 25, 1984, submitted draft Abnormal Operating Procedure (A0P) 2-1 l This procedure was previously reviewed during an inspection discussed in Inspection Report No. 50-309/84-25 and found technically acceptabl On December 14, 1982, the 115kV Mason line, one of the two-offsite sources, was temporarily removed from servic At this time, the second offsite source (115 kV Suroweic line) continued to be in service connected to the reserve station service transformers. However, a degraded voltage condition was observed at these transformers. As a result of this degraded grid voltage condition, the NRC requested the licensee to conduct a study to determine the corrective 1 action which would assure that the commitment in the FSAR l with respect to the offsite sources was me This commit- (
ment was that either of the two 115kV incoming lines, I Mason or Suroweic, is independently capable of supplying the plant auxiliary power requirements. This study, I
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Calculation Number MYC-430, was completed by YAEC on October 25, 1983. The corrective action proposed as a result of this study was to change the reserve trans- f formers' voltage tap setting from tap 3_to tap 4 position (115,050 Volts). The team reviewed the voltag study MYC-430 and verified that the recommendated transformer taps had been changed to satisfy the FSAR -
commitment No unacceptable conditions were identifie j The low degraded grid voltage condition which occurred on .
December 14, 1982 when the 115 kV Mason line was removed !
from service, was due to an increased load growth _between i the Suroweic substation and the Maine Yankee Power 1 l Station. Although the problem was resolved temporarily by- l the higher tap setting discussed above, it may recur in j the future if load growth continues. Although there is an l onload tap changer on the transformer supplying power to )
the 115 kV Suroweic line, it would not have prevented the 1 degraded voltage condition of December 14, 1982. There-fore, the licensee plans to conduct a new voltage study to determine alternate solutions to assure that adequate i
voltage is maintained at the plant-when either 115 kV line ;
is removed from service. The revised voltage study will be done using a computer program, called DAPPER, further discussed in Section 5.4.3 of this repor Cable Ampacity Study In March 1986, Stone and Webster Engineering Corporation prepared a study cf ampacity of selected cables, calcula-tion number E-3. This study has been currently revised as of February 1987. The purpose of this study was to:
Document the capability of feeder cables to switch- 1 gear, motor controls (MCC), and power distribution ;
panels to withstand the maximum continuous current i permitted by the primary protective device Document the capability of feeder cables to the same equipment noted above to withstand short circuit current for the time it takes for the back-up protective relays to operat The results of the study are as follows:
Sixty percent of the' feeder cables are capable of withstanding the maximum continuous current allowed !
by the primary protective device _ _ _ - _ - _ _ _ _ _ _ _ _ _
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I Twenty six percent of these cables can withstand the 1 short circuit current until the backup protective l devices operate, j i The licensee has determined that no corrective action is required for the following reasons:
i The study was initiated because of the need to know if l feeder cables were protected against overload and l short circuit as various load additions and other modifications were being made.
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If this protection is provided for cables at generating facilities, it is considered a positive attribut The Maine Yankee design is consistent with the original design basis stated in FSA ;
The continuous current allowed by the primary trip device may be more than the actual load on the cabl The coincident condition of low probability events (i .e. , a cable faults at the same time that the primary trip does not function) has a very low probabilit However, the licensee has committed that an additional objective not originally covered by the E-3 study will ;
be added to it ; this change will be completed by August 31, 1987 and will document the normal full-load current of swit:hgear, MCCs, and power distribution panels to allow a comparison with the ampacity of the feeder cables and the primary protective devices. (Reference YAEC '
Memorandum, F.D. Baxter to R. P. Shone, dated 1 May 11, 1987). l I
The licensee stated that the result of the above study !
would be made available to the team when completed. This is an unresolved item pending completion of the study and ,
review of its results by NRC (87-12-03). '
c. Short Circuit Studies Stone and Webster Engineering Corporation (SWEC) performed j two short circuit studies recently: (1) Calculation E-5, '
Short Circuit Study-Medium Voltage and (2) Calculation E-2, ;
Short Circuit Study-Low voltage. They submitted the !
results to YAEC for their review in April 1987. These studies were done using the DAPPER computer program further discussed in Section 5.4.3 of this repor :
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l 5 'The above studies were reviewed by the team and the retuits i 4 discussed with YAEC. ,As a result of the above review and discussions, th efoll' owing findings were identified:
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, The Ston'e and Webster study E-5 indicates momentary duty of l
!6.9 kV breakers exceeds the breaker n'omentary rating by f '
- approximately,1.4percentandtheinp.rruptingdutyofthe 4.16 kV breakers exceeds the breaker' rating by approxi-mately 6.7 percen .!
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This situation only occurs under worst-case conditions, which assume that a' diesel generator is connected to.the bus while undergoing its monthly surveillance testing, and that the two motor driven steam generator feed pumps are-running. Without.ths diese? generator and the. feed pumps,
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there is no problem, and the fauit duty is within the rating. The possibility.of a fault occurring under thes j
, worst-case conditions is remot This combined with the I likelihood of the breaker fai' ling'to interrupt a fault current slightly in excess of its rating makes the situa- i tion an extremely low probability even The licensee's analysis indicates that continued operation ;
under these circumstances is considered acceptable for the short term. However, the analysis indicated that plans
. should be drawn up < for a long-term solution- to reduce the fault duty to within ratings. The long-term solution should resolve not anly the present excess fault current, j but those increases in fault' current arising from changes !
in plant operating practices, or load additions. In a ]
memorandum, F. D. Bacer to R. P. Snone, dated 1 March 9, 1987, YAEC recommend that until final solution to l
the problem is determined, plant operation be limited to those large motor loads, as shown in Attachment 1 to the memorandum, which are representative of present practic Any increases over these will worsen the situation by adding to the fault duty imposed on the circuit breaker The licenseo stated that the above limitations on the plant operations would be in place until a final solution as 1 discussed below is achieve The licensee has committed to study modifications to the '
plant electrical system. These modifications would be designed to correct the above short circuit condition an allow for the future addition of plant electrical load The licensee committed to determine' alternative solutions to the problem by August 31,1987 ~ and a final solution by November 30, 198 The licensee will submit a letter to the NRC, by November 30, 1987, providing a plan.and I
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I schedule for correcting the above short circuit conditio )
This is an unresolved item, pending the receipt and review '
by the NRC of the proposed solution (87-12-04).
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In addition to the above finding, the team has the following ]
l observations regarding the short circuit studies: j i
The fault contribution from the 345,000 Volt system has not increased substantially between June 1976 ;
and July 1985. The values used for the initial short 1 circuit study were identified in Central Main Power l (CMP) Letter MYA-19 dated Ju'ne-26, 196 The values I used in the Calculation E-5 were identified in letter j l MYP 85-581 dated July 8, 1985. The fault contribution 1 by the system doesn't appear to be a contributing j factor to the increased fault current duty for the j 4,160 and 6,900 Volt switchgear discussed abov This increase in the fault current duty for the switchgear breakers appears to be the result of the )
licensee using the latest standards for calculating fault current The available fault current at all buses was calcu-lated utilizing ANSI C37.5-1979 as guidance. The l studies included all bus and cable impedances. All 1 components were identified with their respective ;
inductance to resistance ratios which result in more 1 accurate short circuit current value ; Electrical Protection Coordination Study Stone and Webster Engineering Corporation completed the coordination curves for the electrical distribution systems and submitted them to YAEC for review in April 198 ;
The purpose of this study was to ascertain that, when a postulated electrical fault occurs, the primary protective device will clear the fault condition prior to the opera-tion of the backup protective device. Also, there must be sufficient margin to account for component accurac This proper coordination restricts the effect of the electric fault to that portion of the electrical system where the fault has occurred without interruption of power to the unfaulted portion of the syste The team reviewed this study and discussed it with the licensee. The following are significant findings of this study and licensee identified corrective actions to these findings. (Reference: YAEC memorandum, F. D. Baxter to R. P. Shone, dated April 17,1987).
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Inadequate coordination exists on nine (9) feeder breaker Specific corrective action was recommended to correct this lack of coordination. YAEC also recommended that this corrective action take place prior to returning to power from the 1988 refueling 1 outage. None of these breakers are associated with l the Class 1E portion of the electrical distribution !
system. They do not affect safe plant operation.
l Inadequate coordination exists in fifty cases between molded case circuit breakers on the power distribution panels. These breakers do not have thermal trip elements, and their magetic elements are in some cases impossible to coordinate. The licensee evaluated the problem and determined that the short comings are ;
acceptable. However, the team was concerned if any safety related circuits are involve The team requested the licensee to identify the circuits i associated with inadequate coordination and evaluate the effect upon the safety of the plant, should an electrical fault occur within these circuits. The licensee has committed to provide this information to the NRC by August 31, 1987. This is an unresolved item, pending the licensee providing this information and the NRC review of this information (87-12-05). I As the redundant safety related components are generally powered from separate and independent sources, the probability of loosing the redundant componen'.s due to inadequate coordination is smal Based on this, the team determined that the above licensee action is adequate in the interi e. Battery Sizing Study YAEC prepared the study MYC-104 for sizing Batteries 1, 2, 3, 4, and 5 in September 1980 and revised it in l September 198 The purpose of the study was to determine l
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the following:
l l The load profile of each DC bus.
l The battery size necessary to supply this load profil The available spare caoacit Meeting the FSAR Section 8.3.3 committment that Battery 1 and 3 are sized to supply the combined Bus 1 and 3 load and that Batteries 2 and 4 are sized to supply the combined Bus 2 and 4 load. FSAR Section l
8.3.3 ard Question / Answer 8.8 also states that the
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ties between Buses 1 and 3 and between Buses 2 and 4 are provided to facililtate maintenance and at the_ ,
same time permit supply to all buses. The ties are :
not used for any other purpose !
The conclusion of this study was that the batteries had !
adequate capacity to supply their respective individual bus loads as summarized below:
I Load Available Spare Capacity 1 i
Bus 1 75% )
Bus 3 77% d Buses 1&3 Combined 52% ,
Bus 2 45%
Bus 4 63%
Buses 2&4 Combined 23%
Bus 5 0%
J The team reviewed the battery sizing study MYC-104 and discussed it with the licensee. The following are .
observations associated with the above stud The solution method, design criteria, and assumptions were based upon IEEE Std. 485-1978 and industry practice Non- safety related loads have been removed from Batteries 1 and'3 and put on the non-safety related Battery 5. (Batteries 1, 2, 3 and 4 are safety-related). ,
During the 1985 Refueling Outage, the capacity of batteries 1 and 3 were tested. Their capacity was determined to be 84% for Battery 1 and 86% for Battery 3. The IEEE standard 450-1980 recommends replacement within one year after the battery reaches 80% capacity. YAEC recommended that the Batteries 1 and 3 be tested during the 1987 Refueling outage with replacement during the Refueling Outage of 1989. However, the licensee elected to change thes batteries during the 1987 outage. The replacement of Batteries 1 and 3 was done in accordance with modification package EDCR 86-02. Although Battery 3 was approaching end of life, it' was not deteriorating as quickly as Battery However, additional concerns raised over the seismic integrity of aged lead-antimony cells caused the licensee to replace Battery 3 at the same time Battery I was replaced. The licensee has chosen to size the replacement
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Batteries 1 and 3 the same as the original capacity, even though the large non-safety related loads had been removed i and are supplied power from the non-safety related Battery The team reviewed the results of following battery tests:
(a) Station Batteries Rated Load Discharge Test, Procedure No. 3.5.3 for Batteries I and 3, September 1985 and (b)
selected sample of Station Battery Readings - Every other i Month, Procedure No. 3.5.2 for the period of May 1985 through June 1987. The team also reviewed the modification package EDCR 86-02 and inspected all of the batteries.
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The team concluded that the test were conducted in accor- !
i dance with IEEE STD 450-1980. No deficiencies were note l
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l During the review of past capacity tests for Batteries 1 l and 3 to determine approach to end of life, YAEC noted that Batteries 2 and 4 had not been tested since they were j installed, i. e., for a period of 14 year YAEC recom- 1 mended that Batteries 2 and 4 be tested during the 1985 '
refueling outage. The tested capacity of these batteries were 111% for battery 2 and 113% for Battery 4. However, the team expressed a concern about the lack of testing of !
Batteries 2 and 4, that occurred during the fourteen years of installed life. The requirements for surveillance testing of batteries are specified in Technical Specifica-i
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tion 4.5, and are applicable to Batteries 1 and 3 onl l However, the team was concerned for not testing the safety l related Batteries 2 and 4 on similar lines to Batteries 1 )
and The 'icensee is planning to prepare a procedure and !
test Batteries 1 and 3 during the 1989 refueling outag ]
This is an unresolved item pending completion of the above licensee actions including establishment of the related procedures and their review by NRC (87-12-06).
I f. Emergency Diesel Generator Loading Study The YAEC performed a study on the Emergency Diesel Generator Loeding, Calculation number MYC-107, on June 19, 1981. The purpose of this study was to review and update the total load capability and voltage recovery characteristics of each Maine Yankee emergency diesel generator (EDG). The updating was required because of significant load additions and deletions to the diesel generators since the original calculations were. performe The team reviewed the calculation MYC-107,-the FSAR section 8 commitments, and the EDG name plate data and discussed this calculation with the YAEC personnel. The team, has following observations: ,
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. 21 The assumptions and criteria used in the calculation are based upon accepted industry standards and practice The worst case loading is based.upon a concurrent loss of off-site power and an accident (Safety Injection Actuation Signal). The loading steps in the FSAR and MYC-107 are in agreement. This worst cese loading is 98% of EDG-'1A continuous rating (8750 hours0.101 days <br />2.431 hours <br />0.0145 weeks <br />0.00333 months <br />) and 106%
of EDG-18 continuous rating. However, the worst case loading is also 86% of EDG-1A 2000 hour0.0231 days <br />0.556 hours <br />0.00331 weeks <br />7.61e-4 months <br /> rating and 93%
of EDG-1B 2000 hour0.0231 days <br />0.556 hours <br />0.00331 weeks <br />7.61e-4 months <br /> rating and therefore acceptabl The diesel generator short time rating (2000 hoJrs) is listed as 2900 kW in the FSAR and MYC-10 However, the EDG name plate indicates 2850 k The EDG alternator name plate indicates 3575 kVA at 0.8 power factor. This translates to 2860 kW. There-fore, the diesel engine is more limiting than the generato The team discussed with the licensee the short time rating indicated in the FSAR-and the EDG name plate. The licensee will investigate this difference between ratings. The team concluded that EDG Loading is within the design limit l Direct Current Short Circuit Study 4 Stone and Webster Engineering Corporation prepared a study, DC short circuit E-1, in October 1985 with the last revision in July 1986. The purpose of the study was to determine the short circuit currents at selected locations in the DC system to correctly coordinate protective device The team reviewed the study and determined that the assump-tions were valid and the methods of calculations were in accordance with industry practice l 5. License Program to Track Load Growth and to Perform Load Studies
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The licensee is in the process of developing a computer based
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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 L Reporting (DAPPER). The new program is intended to generate l load list (static loading of the buses) and to analyse the system for short circuit and voltage profile considerations
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program can be used for evaluating the adequacy of the breaker
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l interrupting capacities and the relay coordination. The licensee is currently in the process of entering the system I data into the program. The licensee expects the new program to !
be in place within approximately a year. When the new program l is in place, the licensee expects to significantly enhance their "
in-house capability to analyze the system whenever modifications are performe Presently, the licensee has an informal program for tracking the future electrical load growth. Although the informal program is presently capable of tracking the load growth, it -
does not have any formal administrative control. In response to the team's concern for a formal administrative control for this activity, the licensee committed that a formal procedure, I after appropriate reviews, will be issued by August 31, 198 !
This is an unresolved item pending completion of the above licensee action and its review by NRC (87-12-07).
5.5 Independent Measurements and Calculations 5. Independent Measurements The team made a number of independent measurements using an infrared thermometer to confirm the accuracy of transformer temperature indicators and measurements to identify hot spots in the electric. power systems that would indicate overloading or loose connections. This included safety related buses and tran s fo rnie rs . No hot spots were identifie . Independent Calculations l
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, only limited portions of the licensee's calculations were verified by the team. The _
portions of the calculations verified by the team included:
voltage study, cable ampacity study, short circuit studies, coordination study, battery sizing study, emergency diesel l'
generator loading study, and direct current short circuit study. No deficiencies were identifie l 6. Conclusions i;
Two violations, involving lack of proper acceptance criteria (setpoints)
for overcurrent trip devices for safety related (class 1E) 480V breakers, and improperly sized overcurrent devices were identified. Five items remained unresolved at the end of this inspection.
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I The above findings are listed in Attachment 3 of this report which also includes the reference sections where the details of these findings are discussed. The licensee actions and commitments, including actions required to resolve the unresolved items, are also discussed in the reference section j Based on the team's review and inspection, it was concluded that there is reasorable assurance that the present configuration of the electric power systems is capable of supporting safe operation of the plant. However, '
the static (full load) and dynamic (short circuit) duty of the systems appears to be approaching or marginally exceeding their capability under worst case assumptions. The licensee is committed to study these concerns i and expeditiously take appropriate corrective actions. The licensee's l commitments and ongoing actions should improve the capability of the l electric power systems to support safe plant. operatio . Unresolved Items Unresolved items are matters for which more information is required in order to ascertain whether they are acceptable, violations, or deviations. Five unresolved items are discussed in various sections of this report as listed in Attachment .
! Exit Interview Attachment 4 is the list of persons contacted during the inspection. At the conclusion of the inspection on June 5,1987, the . inspection team met with the licensee representatives, denoted in Attachment 4. 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 information. The licensee agreed that the inspection report may be pieced in the Public Document Room without prior licensee review for proprietary information (10 CFR 2.790).
No written material was provided to the licensee by the tea I l
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ATTACHMENT 1
SIMPLIFIED SKETCH OF ELECTRICAL POWER SYSTEMS '
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// Fv ?? My IIS KV 115 k V
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i ,l ffy ai4 y" Mg a26 N a 16 M%
N al4 }
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} NC NO NC ]@
6900 V BUS I 6900 V BUS 2 l l l )NC { } NO [. NO NC [] NO
60 v f Bus 3 4160 V BUS 5 4160 V BUS 6 4160 V BUS 4 l } NC f} UC {l] NC [1)NC [1]NC []NO ]NO NC NC ( NC NC []NC l
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DGIAh (hDG IB
[ l i 1 i l N a309 a 410 ff a 313 a507 a60B a 414 y a 311 y* d a 412 r I i l i INC )ho ) NC )NC )NO ) NC )NO )NC ) NC )NC )NO NC l
4tto V HUS **
l } l 400 v BUS 10 480 V BUS 13 l ) l l l l l r 480 V BUS 7 480 V BUS 8 400 V bus 14 480 V BUS ll 480 V BUS 12 F 10 8.3 s ONE L INE DI AGR AM AUXILI ARY POWER SYSTE M M AINE TAhMEC ATOMIC PvWER COMPANY
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ATTACHMENT 2 DOCUMENTS REVIEWED
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1. Final Safety Analysis Report Sections i
1.2, Principal Design Criteria (GDC)
Appendix A, Cenformance to AEC Design Criteria Appendix B, Quality Assurance Program 8,0, Electrical System !
2. Drawings Orawing# Title Revision 11550-FE-1A, Main One Line Diagram 11 11550-FE-1E 4160V One Line Diagram, S '
11550-FE-1F 4160V One Line Diagram, S ,
11550-FE-1H 480V One Line Diagram Unit Substation, 11 l Sh. 2 11550-FE-1J 480V One Line Diagram Unit Station, 6 S <
11550-FE-1L 480V One Line Diagram MCC-7A, 8A &l3B 21 11550-FE-1M One Line Diagram 480V MCC-781, 8B &881 2 11550-FE-1R One line diagram 480V MCC-10B, 128, 12 l 12C & 12E '
11550-FE-10 One line diagram 480V MCC-11A, 19 1 12A & 14B l
11550-FE-1K One line diagram 480V MCC-110, 120, 14 13A & 14A 11550-FE-1T 120 VAC one line diagram (SHI) vital 17 bus 1, 2, 3 & 4 11550-FE-3DAT, Wiring diagram rear mounted equipment, main control board sect "C", Sh. 37 21
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Drawing # Title Revision
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11550-FE-3 DAY Wiring diagram - vital bus 1A 2A, 3A, 5 4 Control room north wall SH37A 11550-FE-IT One line diagram 120 VAC Vital Bus 1A, 2 2A, 3A, 4A, Sh.2 Vital Bus IA, 2A, j 3A, 4A SH2 11550-FE-15 125V DC one line diagram 6 Quality Assurance and Administrative Control Document 3.1 OA Manual Sections i
Section# Title Organization i
I QA Program !
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II Procurement Document Control Instructions, Procedures and Drawings V Document Control VI Control of Purchased Material, Equipment and Services VII Identification and Control of Material, }
Parts and Components X Test Control l
l Inspection, Test and Operating Status X Nonconforming Materials, Parts and Components XI Corrective Action l
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i 3.2 QA Manual Implementing Procedures
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Procedure # Title- Revision 0-02-1 Classification of Nuclear Systems 0 0-03-1 Control of Activities Affecting Design 1 0-06-01 Document Control 0 .!
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0-06-04 10 CFR 50.59 determination ,
I j 3.3 Plant Engineering Manual Class A Procedures Procedure # Title Revision
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17-21-2 Engineering Design Change Request - 3 l Maine Yankee 17-21-3 Engineering Design Change Request - 2 (YNSD)
17-21-5 Engineering Calculations & Analyses 1 l 17-21-6 Design Verification 3 17-21-7 Safety Analysis 1 l
17-22-1 Document Revision Procedure 4 17-23-1 Design Change Installation Instructions 4 17-23-2 Job Order Instruction 2 1 17-23-3 Submittal of Completed Design Package 2 for Files 17-23-4 EDCR Functional Test Instructions 1 l
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4. Modification Packages i l
Mod. Package # Title i
EDCR 80-45 Deleted One 350 HP SCCW motor from ti,e Emergency Automatic Loading of Cus 5 and one 350 HP PCCW motor from the Emergency Automatic Loading of Bus 6 EDCR 81-06 Added Subbuses lA, 2A, 3A and 4A to vital buses 1, 2, 3 and 4, respectively EDCR 86-02 Replaced Batteries 1 and 3 with new identical batterie i EDCR 83-09 Transferred 75 HP Auxiliary Charging Pump P7 from MCC 8A to MCC 98 to MCC 981 i
EDCR 84-64 Added 30 kW Unit Heater to MCC 11A !
EDCR 73-05 Added 500 HP steam Generator Auxiliary Feed Pump ,
P25C to Bus 5 PA 9-79 Added Two 20 HP Breathing Air compressors to MCC 11A PA 20-81 Added 25 HP TDFP Main LO Pump to MCC 13A MRs 1269-80 Replaced Six EC overcurrent Trip Devices on 480V Switchgear with SST Device . Load Studies and Analysis l
Doc.# f Title Revision j S&W Calculations Electrical Calculation Binder Various !
I thru 74 (Calculations done prior to OL) (dated June i 1967 thru July !
1972) !
S&W Calculation E-1, DC Short Circuit Study 3 S&W Calculation E-2, Short Circuit Study, Low Voltage 2 S&W Calculation E-3, Cable Ampacity 2 i
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S&W Calculation E-4, Verification and Validation {
of Software 1 i S&W Calculation E-5 Short Circuit Study, Medium Voltage 2 q (Unnumbered) Protective Device Coordination Curves None ;
i YAEC Calc. MYC-104 Battery sizing, Batteries 1, 2, 3, 4 and 5 1 l YAEC Calc. MYC-107 Emergency Diesel Generator Loading 0 YAEC Calc MYC-430- Auxiliary Power Systems Voltage Study 0 j (Un-numbered) Coordination Curves (Done for None l Appendix R Modifications)
I 6. Other Documents 6.1 Specifications Doc # Title _ Revision l MYS-244 Reserve Station Service Transformer Last '
l MYS-271 Generator Transformer 10/12/68 ;
MYS-404 Unit Station Service Transformer 06/14/63 MYS-465 6900V and 4, 1600 Metal Clad Switchgear Last (
MYS-525 Emergency Diesel Generator 11/18/68 l
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MYS-710 Unit Subs- tion 12/10/68 MYS-1393 Motor Centrol Centers 9/17/69 l
MYS-1460 600V Insulated Power cable Last l
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6.2 Apnormal Operating Procedunes ( A0Ps)
Proc Title Revision 2-12 Bus 5 or Bus under voltage 6 2-16 Partial Loss of Load 4 2-46 Loss of Offsite Power 14 2-90-1 Plant Shutdown Plan for . 5-Fire in Control Room and/or Station Blackout 6.3 Emergency Operating Procedures (EOPs)
ECA- Loss of All AC Power 0 ECA- Loss of All AC Power Recovery, SI Not required 0 ECA- Loss of all AC Power, 0 with SI 6.4 Surveillance Procedures Proc No Title 3. Monthly Station Battery Reading 8 (Results of test performed as 5/14/85, 9/3/85, 12/24/85, 3/3/87, 6/1/87 3. Station Batteries Rated Load Discharge Test (Results of test performed on 9/21/85)
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ATTACHMENT 3 LIST OF INSPECTION FINDINGS FOR DETAILS _1 ITEM N DESCRIPTION REFER TO SECTIONS Violations (87-12-01) The presence of Installed Over- current Trip Devices different than the Plant Design Drawing (87-12-02) Lack of Acceptance Criteria for j calibrating the 480V Breaker ,
Overcurrent Trip Device I Unresolved Items ]
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(87-12-03) Static Load Study of Onsite Electric Power System 5. (87-12-04) Short Circuit Duty of G.9 kV 5. and 4.16kV Breakers -
(87-12-05) Coordination Study on Molded Case 5. Circuit Breakers ;
j (87-12-06) Batteries 2 and 4 Acceptance Testing 5. (87-12-07) Administrative Control Procedure 5. to Track Load Growth
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l ATTACHMENT 4 )
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PERSONS CONTACTED 1 1. Maine Yankee Atomic Power Company (MYAPCJ R. Bickford, Specialty Training Section Head l S. Evans, Licensing Engineer l J. Hebert, Manager-PED !
S. Morrision, Supervisor-Electrical Maintenance A. Parker, Lead Electrician D. Ross, Supervisor - Engineering Assistance
- Whittier, Manager - Nuclear Licensing 2. Yankee Atomic Electric Company (YAEC)
l *P. Anderson, Maine Yankee Project Manager
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- F. Baxter, Lead Electrical Engineer l
l *K. Hyyrynen, Senior Engineer l
R. Shone, Engineering Manager i
- S. Urbanowski, Principal Engineer 3. Nuclear Regulatory Commission (NRC) ;
C. Holden, Senior Resident Inspector
- Denotes those present at the exit meeting l
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