ML18153D277

Application for Amends to Licenses DPR-32 & DPR-37,revising TS to Address Operation W/Control Rod Urgent Failure Condition

ML18153D277
Person / Time
Site:	Surry
Issue date:	03/19/1993
From:	Stewart W VIRGINIA POWER (VIRGINIA ELECTRIC & POWER CO.)
To:	NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
Shared Package
ML18153D278	List: ML18153D277 ML18153D279
References
93-121, NUDOCS 9303290197
Download: ML18153D277 (17)

Text

e e VIRGINIA ELECTRIC AND POWER COMPANY RICHMOND, VIRGINIA 23261 March 19, 1993 United States Nuclear Regulatory Commission Serial No.93-121 Attention: Document Control Desk NL&P/ETS/JWH: RO Washington, D. C. 20555 Docket Nos. 50-280 50-281 License Nos. DPR-32 DPR-37 Gentlemen:

VIRGINIA ELECTRIC AND POWER COMPANY SURRY POWER STATION UNITS 1 AND 2 PROPOSED TECHNICAL SPECIFICATIONS CHANGES OPERATION WITH A CONTROL ROD URGENT FAILURE CONDITION Pursuant to 1O CFR 50.90, the Virginia Electric and Power Company requests amendments, in the form of changes to the Technical Specifications, to Facility Operating License Nos. DPR-32 and DPR-37 for Surry Power Station Units 1 and 2, respectively. The proposed changes address operation with a control rod urgent failure condition (control rod assemblies immovable due to failures external to the individual control rod drive mechanisms, i.e. programming circuitry, but remaining trippable). The proposed changes will allow plant personnel to effect repairs to the Rod Control System in an orderly manner while continuing to ensure that the control and shutdown banks are capable of performing their safety function as designed. In addition, the surveillance frequency for control rod assemblies is being changed to monthly.

A discussion of the proposed Technical Specifications changes is provided in . The proposed Technical Specifications changes are provided in . It has been determined that the proposed Technical Specifications changes do not involve an unreviewed safety question as defined in 1O CFR 50.59 or a significant hazards consideration as defined in 1O CFR 50.92. The basis for our determination that these changes do not involve a significant hazards consideration is provided in Attachment 3. The proposed Technical Specifications changes have been reviewed and approved by the Station Nuclear Safety and Operating Committee and the Management Safety Review Committee.

Should you have any questions or require additional information, please contact us.

Very truly yours, i/~~-

w. L. Stewart Senior Vice President - Nuclear Attachments I

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cc: U. S. Nuclear Regulatory Commission Region II 101 Marietta Street, N. W.

Suite 2900 Atlanta, Georgia 30323 Mr. M. W. Branch NRC Senior Resident Inspector Surry Power Station Commissioner Department of Health Room 400 109 Governor Street Richmond, Virginia 23219

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e COMMONWEALTH OF VIRGINIA )

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COUNTY OF HENRICO )

The foregoing document was acknowledged before me, in and for the County and Commonwealth aforesaid, today by W. L. Stewart who is Senior Vice President -

Nuclear, of Virginia Electric and Power Company. He is duly authorized to execute and file the foregoing document in behalf of that Company, and the statements in the document are true to the best of his knowledge and belief.

Acknowledged before me this /9~ay of ( /Jli.._tlA.L1/> , 19.:t.1.

My Commission Expires: ( ~*'?/ , 19.1£.

~ Notary Public (SEAL)

e Attachment 1 Discussion of Changes

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....,YYYY>'IYI I YI YI I 11 \192 Introduction Virginia Electric and Power Company proposes revisions to Technical Specifications (TS) 3.12.A, Control Bank Insertion Limits; 3.12.B, Power Distribution Limits; 3.12.C, Inoperable Control Rods; 3.12.D, Core Quadrant Power Balance; 3.12.E, Rod Position Indicator Channels; and Table 4.1-2A, Minimum Frequency for Equipment Tests, for Surry Power Station Units 1 and 2. These proposed changes address operation with a rod urgent failure condition (control rod assemblies immovable due to a failure external to the individual control rod assembly drive mechanisms, i.e., programming circuitry, but remaining trippable), including limited operation with one control or shutdown bank inserted slightly below its insertion limit.

Additional changes involving explicit definition of actions and time limits for certain Limiting Conditions for Operation where none are currently defined are also added.

Certain administrative changes are proposed which provide consistency and readability, through capitalization of defined terms, standardization of operating mode nomenclature, and deletion of obsolete figures. Changing of the control rod assembly partial movement surveillance test frequency from biweekly to monthly is also proposed.

A discussion of these proposed changes is provided in the following:

1. The existing TS 3.12.A.5 provides an exemption from the insertion limits for physics testing and periodic exercise of individual control rod assemblies. The exemption for control rod assembly testing is required because the insertion limit for the shutdown banks and control banks A, B and C corresponds to the fully withdrawn position for full power operation. The proposed TS 3.12.A.6 supplements the exemption by defining a limit on both time and insertion if a bank is immovable due to failures external to the control rod assembly drive mechanisms (i.e., in a power or logic cabinet). Specifically, a maximum of one control or shutdown bank (with the exception of Control Bank D) may be inserted below its insertion limit for up to 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> during diagnosis and repair of the Rod Control System provided that:

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a. the controi or shutdown bank is inserted no mOie than 18 steps belmv the insertion limit as measured by the group step counter demand position indicators,

b. the affected bank is trippable,

c. each shutdown and control rod is aligned to within +/- 12 steps of its respective group step counter demand position, and

d. the shutdown margin requirement of Specification 3.12.A.3.c is determined to be met at least once per 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br />.

If the affected bank is not restored to above the insertion limit within the allowed 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br />, the unit must be placed in hot shutdown within the next 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br />.

This change will provide a reasonable amount of time to effect repairs to the Rod Control System while continuing to ensure that the control and shutdown banks are capable of performing their safety function as designed.

2. TS 3.12.C.3 currently defines actions to be taken if more than one control rod assembly in a given bank is immovable due to a failure external to the individual control rod assembly drive mechanism (i.e., in a power or logic cabinet) but remains trippable. The current specification provides up to 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> to restore the affected control rod assemblies to operable status. The proposed change would treat control banks which cannot be moved by the Rod Control System as operable provided:

a. the affected banks are trippable, and

b. each control rod assembly in the affected bank is aligned to within +/- 24 steps of its respective group step counter demand position during the "Thermal Soak" period (up to one hour in 24 following bank motion below 50% power) and to within +/- 12 steps otherwise.

This change is proposed in recognition of the fact that control and/or shutdown banks which are trippable, above the insertion limits and within the analyzed alignment requirements are fully capable of performing their intended safety function, even if they cannot be moved by the Rod Control System.

3. A paragraph has been added to TS 3.12 Basis to discuss the revised definition Page 2 of 13

of controi rod assembly operability and the 72 houi pmvision foi tempoiary operation with a bank up to 18 steps below its insertion limit.

4. Additional changes to TS Section 3.12 are proposed to add action requirements and time limits where none are specified, and to make minor editorial corrections. The current TS 3.12.A.1 and 3.12.A.2 require that shutdown and control rod assemblies satisfy the applicable insertion limits, but do not specify actions to be taken if these limits are not met. The proposed revisions add action requirements with specific time limits.

In addition, the current TS 3.12.B.6 and 3.12.B.7 specify actions to be taken if quadrant power tilt exceeds the maximum allowable value, but do not specify time limits for these actions. Time limits are therefore proposed. Throughout TS Section 3.12, editorial changes such as capitalization of defined terms and standardization of operating mode names are proposed.

5. Figures 3.12-4A and 3.12-48, which specify control rod assembly insertion limits for two loop operation, are eliminated, since two loop power operation is prohibited by Specification 3.3.A.11. The pages for previously deleted figures (i.e., TS Figures 3.12-2, 3, 5, 6, 7 and 9) are removed. Figures 3.12-8 and 1O are renumbered as Figures 3.12-2 and 3, respectively.

6. Revision of the control rod assembly exercise test frequency specified in TS Table 4.1-2A from biweekly to monthly is proposed.

Background

Rod Urgent Failure Surry Technical Specifications require periodic testing of each control and shutdown control rod assembly bank in the core during power operation to ensure that the control rod assemblies are trippable, i.e., able to fall into the core upon receipt of a reactor trip signal. This testing involves partial movement of each control rod assembly not fully inserted into the core at least once per 14 days. This is typically done at or near full power, one bank at a time. Current procedures call for sequential insertion and withdrawal of 18 steps for the bank being tested. .

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e Since each of the control and shutdown banks except control bank D are required to be fully withdrawn from the core at full power, special test exceptions are currently included in the control rod assembly insertion limit Technical Specifications for the case of control rod assembly surveillance testing. The current Specifications are not prescriptive concerning the allowed duration of the test mode.

Surry Power Station has occasionally experienced some difficulty with control rod assembly surveillance testing. Specifically, control rod urgent failure alarms are sometimes received during the test. The urgent failure alarm is indicative of an internal failure in the rod control equipment that has affected the ability of the system to move control rod assemblies. Automatic control rod assembly motion and overlapped control rod assembly motion are stopped on an urgent failure. The failure may be in either the system logic cabinet or in the power cabinet and may take some time to diagnose.

A power cabinet urgent failure can be caused by coil current regulator failure, a phase failure (excessive ripple in coil voltage), a logic error (simultaneous zero current order to the stationary and movable grippers) or a multiplex error (current sensed in the movable or lift coils for a control rod assembly or group of control rod assemblies not selected by the multiplex function). The system responds to these conditions via failure detection logic which overrides the existing current orders from the logic cabinet with a low current order to each set of grippers in that cabinet. This is done to prevent spurious control rod assembly drops due to the failure. Also an "inhibit" signal is sent to the logic cabinet pulser unit to stop all control rod assembly bank motion, in or out, in auto or manual. Movement of individual banks which are not associated with an alarmed cabinet may still be accomplished by selection of individual bank operation on the control board.

An urgent failure in the logic cabinet can be caused by pulser failure, slave cycle failure or loose circuit cards. An "inhibit" signal is sent to the pulser which stops auto and manual control rod assembly motion but still allows individual banks to move.

An urgent failure condition during control rod assembly surveillance testing may result in an immovable but trippable control or shutdown group or bank up to 18 steps below the insertion limits. In addition, there is a potential that one or more immovable groups Page 4 of 13

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or banks may occur during power maneuvers (e.g. during turbine valve freedom testing) where the insertion limits are fully met but the affected control rod assemblies cannot move, but remain trippable.

Surry TS 3.12.3.C currently provides two hours for troubleshooting and repair prior to bringing the unit to hot shutdown in six hours in the case of control rod assembly urgent failure. A one-time extension of the troubleshooting and repair period to 50 hours5.787037e-4 days <br />0.0139 hours <br />8.267196e-5 weeks <br />1.9025e-5 months <br /> was granted by the USNRC in the form of a Temporary Waiver of Compliance for operation of Unit 1 in 1992.1 The proposed changes provide needed operational flexibility in repairing Rod Control System problems which do not compromise the ability of the control rod assemblies to perform their design safety function.

Additional Action Times The changes pertaining to action times are proposed because many of the existing Surry Technical Specifications were prepared prior to the Standard Technical Specifications (STS) and either do not contain action statements for certain conditions or contain action statements with no time limits. This creates the potential for unnecessary entry into TS 3.0.1 when the requirements of a limiting condition for operation are not met.

Editorial Changes Editorial changes are necessary to correct inconsistencies in the capitalization of defined terms as well as in the use of operating mode names. In addition, previously deleted figures are being removed from the Technical Specification. The remaining figures are being renumbered accordingly.

Control Rod Assembly Surveillance Frequency A review of recent Surry test experience (in excess of 4000 individual control rod assemblies tested) revealed no instances of mechanically stuck control rod assemblies identified during the control rod assembly surveillance. The test experience supports the proposed relaxation of the frequency from biweekly to monthly. Furthermore, this proposed change is consistent with the Standard Technical Specifications.

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Specific Chanaes

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Virginia Electric and Power Company is proposing modifications to the Technical Specifications that pertain to the operation of control and shutdown control rod assemblies. These changes are as follows:

1. A proposed new TS 3.12.A.6 supplements the existing exemption to the control and shutdown bank insertion limits for physics and control rod assembly surveillance testing by defining a limit on both time and insertion allowed for diagnosis and repair of a failure of the Rod Control System which is external to the control rod assembly drive mechanisms (i.e., power or logic cabinet failure).

Specifically, a maximum of one control or shutdown bank may be inserted below its insertion limit for up to 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> provided that the bank is inserted to no more than 18 steps below the insertion limit, the bank is trippable and the shutdown margin requirement of Specification 3.12.A.3.c is determined to be met at least once per 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br />. Additionally, the group height alignment limits of+/- 12 steps from the group step counter demand position are imposed.

The technical basis supporting this proposed change is as follows:

a. The shutdown and control rod assemblies will remain fully trippable and, therefore, capable of performing their intended safety function.

b. The radial peaking factor (F~H) will be checked for the allowed conditions for each reload core by modeling the testing of each control and shutdown bank using the NRC approved methods discussed in Reference 2. Based on the results of these calculations, verification will be made that the DNBR criterion for ANS Condition II (UFSAR Chapter 14.2) accidents initiated from the test condition will continue to be met.

Through this reload design process, it will be verified that the test controls for test bank and controlling bank (i.e., Bank D) insertion are appropriate to ensure that this DNBR criterion is met for each control rod assembly surveillance test throughout the cycle.

c. During the proposed 72 hour8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> repair period, insertion below the insertion limit is restricted to one control or shutdown bank at a time. Concurrent Page 6 of 13

e control rod assembly misalignment (i.e., misalignment cf individual control rod assemblies from their group step counter demand position by more than +/- 12 steps) is not allowed. The insertion of the affected bank below the limit is constrained by the peaking factor requirements discussed above and is no more than 18 steps. Because of these constraints, the impact on core reactivity and power distribution is very small. The shutdown margin is specifically reconfirmed every 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> during the repair period. Explicit analytical checks on the radial power distribution during the test/repair period are performed as part of the reload safety evaluation process.

2. The proposed change to TS 3.12.C.3 would treat control banks which cannot be moved by the Rod Control System as operable provided:

a. the affected banks are trippable, and

b. all control rod assemblies in the affected banks are aligned to within+/- 24 steps of their respective group step counter demand positions during the "Thermal Soak" period (up to one hour in 24 following bank motion below 50% power) and to within +/- 12 steps otherwise.

This change is proposed in recognition of the fact that control and/or shutdown banks which are trippable, above the insertion limits and within the analyzed alignment requirements are fully capable of performing their intended safety function, even if they cannot be moved by the Rod Control System. The UFSAR accident analyses take no credit for operation of either manual or automatic rod control. (In certain instances the UFSAR accidents are analyzed for both the manual and automatic rod control cases, but in no instance is the automatic rod control required to demonstrate that applicable acceptance criteria are met.)

3. A paragraph has been added to TS 3.12 Basis to discuss the revised definition of control rod assembly operability and the 72 hour8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> provision for a trippable bank which may be temporarily below the insertion limit by a limited amount due to a Rod Control System malfunction during control rod assembly surveillance testing.

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4. The proposed changes to TS 3.12.A 1 would require that, with a shutdm*.m control rod assembly not fully withdrawn, the control rod assembly be fully withdrawn within one hour or declared inoperable. The proposed change to TS 3.12.A.2 would require that, with a control bank inserted beyond the applicable insertion limit, within two hours the control bank be restored to within the limit or thermal power be reduced to the level allowed for the applicable group position.

Otherwise, the unit must be in hot shutdown within six hours.

These proposed action requirements and time limits are consistent with those of the Westinghouse Standard Technical Specifications (NUREG-0452, Revision 4). The time allowed for restoring shutdown or control rods to within insertion limits provides an acceptable time for evaluating and correcting minor control rod assembly positioning problems without allowing the unit to remain in an abnormal condition for an extended period.

5. The proposed change to TS 3.12.B.6, for quadrant to average power tilt exceeding 2%, imposes a time limit of two hours to either determine the hot channel factors and adjust power level accordingly, or to reduce power level 2% for each 1% of quadrant power tilt. A time limit of four hours is specified for reducing the high neutron flux trip setpoint. For quadrant power tilt exceeding 10%, the proposed change would add a time limit of 30 minutes to reduce power level 2% for each 1% of quadrant power tilt. Four hours is again specified for reducing the high neutron flux trip setpoint.

In TS 3.12.B.7, for quadrant power tilt exceeding 2% for 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> and design hot channel factors for rated power exceeded, a time limit of four hours is added for reducing the high neutron flux, overtemperature 8T and overpower 8T trips.

In addition a time limit of four hours is added to reduce the overtemperature 8T and overpower 8T trips should the quadrant power tilt exceed 2% for 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> and the design hot channel factors for rated power are not determined.

The proposed time limits are consistent with those in the Westinghouse Standard Technical Specifications (NUREG-0452, Revision 4). The time limits proposed for making power reductions *and setpoint changes permit these actions to be accomplished in a controlled manner without allowing an abnormal condition to exist for an extended period.

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6. The proposed administrative changes to capitalize defined terms, standardize operating mode names, and correct grammar throughout TS Section 3.12 are provided for clarification purposes and do not change any limiting conditions for operation, action statements or surveillance requirements.

7. The proposed change to Table 4.1-2A modifies the control rod assembly exercise test frequency from every two weeks to monthly. The basis for this change is discussed in the following section.

8. Figures 3.12-4A and 3.12-4B, Control Bank Insertion Limits for 2 Loop Normal Operation for Units 1 and 2, respectively, are eliminated. These figures are no longer applicable to Surry, because Specification 3.3.A.11 prohibits power operation with less than three reactor coolant loops operating. In addition, the pages for previously deleted figures are removed and the remaining figures renumbered accordingly.

Safety Sic nificance The safety evaluation which supports these proposed modifications to the Specifications is summarized as follows:

a. Operation with a bank (except D Bank) below the insertion limits by up to 18 steps will not cause core radial peaking factors which result in violation of the applicable DNB limits for ANS Condition II transients.

b. Operation with a bank (except D Bank) below the insertion limits by up to 18 steps will not result in shutdown margins lower than assumed in the accident analyses and required by Specification 3.12.A.3.c. This will be assessed during the reload core design process and reconfirmed during the repair period.

c. Since a and b above apply and the control rod assemblies will remain fully trippable during the repair period, the results and conclusions of the UFSAR for anticipated (i.e., ANS Condition II) transients, such as uncontrolled control rod assembly withdrawal, remain unchanged.

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d. Because the duration of such operation is limited to 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br />, the risk of having a higher severity (i.e., ANS Condition Ill or IV) transient, such as control rod assembly ejection, during this interval is negligibly small. Because of this negligible risk, the impact of the proposed Specification changes on the UFSAR results for these classes of accidents has not been explicitly calculated. This is a similar approach to the existing Technical Specifications treatment of a single inoperable control rod assembly (existing TS 3.12.C.5).

The existing inoperable control rod assembly Specification requires evaluation of certain UFSAR Chapter 14 accidents within 5 days of identification of the misaligned control rod assembly condition. This evaluation is required to support continued power operation (i.e., beyond 5 days) with an inoperable control rod assembly.

e. A requirement for power reduction in response to a control rod assembly urgent failure alarm with a single bank up to 18 steps below the insertion limits is not warranted since 1) the perturbation to the normal operation power distribution will be much less severe than that of a fully misaligned single control rod assembly, 2) by design, steady state and Condition II transient criteria will be met for full power conditions, and 3) the rod urgent failure condition may render the capability to manually insert control banks unavailable, which could severely restrict the operator's ability to control axial power distribution swings to within the TS limits during a subsequent power reduction.

f. Occasional operation without manual control rod assembly insertion capability will not invalidate any of the accident analyses in UFSAR Chapter 14 since credit is not taken for this control mode in the analyses. Manual control rod assembly insertion is listed as a contingency action for Anticipated Transient without Scram (ATWS) in the Emergency Operating Procedures and is considered in the generic assessment of ATWS risk in Reference 3. However the major contributor to limiting ATWS risk is the ATWS Mitigation System Actuation Circuitry (AMSAC), which provides a turbine trip, auxiliary feedwater initiation, and control rod assembly drive motor generator set breaker trip which is diverse from the reactor protection system. Therefore, temporary operation without manual control rod assembly insertion capability will have a negligible impact on ATWS risk.

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g. Additional proposed changes add action statements and time limits to TS Section 3.12 where none are currently specified. The proposed changes add action statements and time limits to allow operation for one to two hours, respectively, while shutdown or control rods are returned to within their insertion limits.

Operation for this brief period of time with shutdown or control rods below their insertion limits or with a radial power imbalance will have negligible safety consequences. The time limits being added to existing action requirements allow these actions to be accomplished in an expeditious but controlled manner.

h. The proposed editorial changes are administrative in nature and have no effect on plant operation. They serve to enhance consistency and clarity within the Specification.

i. The proposed monthly surveillance test frequency for control rod assembly testing will continue to provide an adequate basis for ensuring control rod assembly operability, as industry experience with the Standard Technical Specifications demonstrates. A review of recent Surry test experience (in excess of 4000 individual control rod assemblies tested) reveals no instances of mechanically stuck control rod assemblies identified during control rod assembly testing. Therefore, implementation of a longer interval between tests is justified.

Conclusion This assessment of the proposed changes has demonstrated that the probability and consequences of the design basis accidents analyzed in the UFSAR are not increased with a 72-hour allowance for operation with one immovable but trippable control or shutdown bank below its insertion limit. The proposed change will result in a small increase in the probability that, at any given time, a control or shutdown bank will be inserted slightly below (i.e., up to 18 steps) its insertion limit. However, by design, the control and shutdown banks will continue to meet the safety analysis criterion for steady state and ANS Condition II (moderate frequency) transients.

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e The allowed misalignment is not a malfunction of equipment important to safety in this case. Therefore, the probability of a malfunction is not increased. Limiting the allowed time for operation with control rod assemblies immovable but trippable and with a control or shutdown bank below the insertion limit eliminates the need for consideration of this condition coincident with any of the low frequency (ANS Condition Ill or IV) design basis accidents. This is consistent with the philosophy of the Westinghouse Standard Technical Specifications (NUREG-0452, Revision 4), which require evaluation of events such as rod ejection to be completed after five days of operation with a misaligned control rod assembly.

The proposed additions of explicit shutdown action times, improvements to mode definition usage and capitalization, and the proposed ,change to the control rod assembly surveillance interval have no impact on the accident analysis initial conditions, assumptions, frequency of initiation or consequences. The margin of safety as defined in the bases of the Technical Specifications has not been reduced because current core design limits continue to be met for the accidents of concern.

Therefore, it is concluded that the proposed changes to the Technical Specifications do not create an unreviewed safety question as defined in 1O CFR 50.59.

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• - References

1. Letter from S. D. Ebneter, USNRC to W. L. Stewart, Temporary Waiver of Compliance to Repair Control Rod Urgent Failure Circuitry in the Control Rod Drive System for Surry Unit 1, Docket 50-280, May 7, 1992.

2. VEP-FRD-42, Rev. 1-A, "Reload Nuclear Design Methodology," September 1986.

3. WCAP-11993, Joint Westinghouse Owners Group/ Westinghouse Program, Assessment of Compliance with ATWS Rule Basis for Westinghouse PWRs, Westinghouse Electric Corporation, December 1988.

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