IR 05000387/1998008

Insp Repts 50-387/98-08 & 50-388/98-08 on 980601-30. Violations Noted.Major Areas Inspected:Events,Significance, Reportability & C/As for Nonconformance in EDG Fuel Oil Sys

ML17164A734
Person / Time
Site:	Susquehanna
Issue date:	08/06/1998
From:	NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I)
To:
Shared Package
ML17164A732	List: IR 05000387/1998008 ML17164A731 ML17164A733
References
50-387-98-08, 50-387-98-8, 50-388-98-08, 50-388-98-8, NUDOCS 9808130279
Download: ML17164A734 (38)

Text

U. S. NUCLEAR REGULATORY COMMISSION

REGION I

Docket Nos:

License Nos:

50-387, 50-388 NPF-14, NPF-22 Report No.

50-387/98-08, 50-388/98-08 Licensee:

Pennsylvania Power and Light Company 2 North Ninth Street Allentown, Pennsylvania 19101 Facility:

Susquehanna Steam Electric Station Location:

P.O. Box 35 Berwick, PA 18603-0035 Dates:

June 1 through June 30, 1998 Inspectors:

Approved by:

K. Jenison, Senior Resident Inspector J. Richmond, Resident Inspector

, Clifford Anderson, Chief Projects Branch 4 Division of Reactor Projects

9808%30279 980806

'DR ADOCK 05000387

PDR

EXECUTIVE SUMMARY Susquehanna Steam Electric Station (SSES), Units 1 5 2 NRC Inspection Report 50-387/98-08, 50-388/98-08 This special inspection was conducted to review events, significance, reportability, and corrective actions for a nonconformance in the emergency diesel generator fuel oil system.

In 1990, a PP5L safety evaluation for a facility modification concluded a Technical Specification (TS) revision was involved for a'proposed change to the diesel day tank minimum volume. The safety evaluation failed to identify the proposed change as an unreviewed safety question.

PP5L did not obtain NRC approval prior to implementing the change and did not submit a TS change until 1996. This is considered a violation of 10 CFR 50.59 requirements.

However, this violation is not cited, based on the exercise of discretion in accordance with Section VII.B.6of the Enforcement Policy..-

In 1990 and 1991, PPSL identified the fuel oil transfer pump'automatic start level-switch setpoints in the emergency diesel generator day tanks did not meet the American National Standards Institute (ANSI) requirement to ensure a day tank minimum fuel oil volume sufficient for 60 minutes of operation at the level where fuel oil is automatically added to the day tank, at rated load, plus a 10% margin.

PP&L documented this nonconforming condition in Nonconformance Report 90-0173 and engineering study SEA-ME-332, and implemented administrative controls, as compensatory measures, but failed to effect timely resolution.

The failure to effect timely resolution of this nonconformance is considered a violation of 10 CFR 50 Appendix B, Criterion XVI, Corrective Actio TABLE OF CONTENTS EXECUTIVE SUMMARY

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E2 Engineering Support of Facilities and Equipment E2.1 Emergency Diesel Generator Day Tank Minimum Volume

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V. Management Meetings.............. ~........

X1 Exit Meeting Summary........... ~...

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~ 6.6 ATTACHMENTS Attachment 1 - Inspection Procedures Used

- Items Opened, Closed, and Discussed

- List of Acronyms Used Attachment 2 - Susquehanna SES Evaluation of NRC Questions on Emergency Diesel Generator Fuel Oil Day Tanks Attachment 3 - PP&L Letter to NRC PLA-3400, dated June 7, 1990, "Susquehanna Steam Electric Station Unreviewed Safety Question"

Re ort Details III. En ineerin E2 Engineering Support of Facilities and Equipment E2.1 Emer enc Diesel Generator Da Tank Minimum Volume a.

Ins ection Sco e 37551 The inspectors reviewed the Technical Specification (TS) bases and the Final Safety Analysis Report (FSAR) design description associated with a revised operability determination for an emergency diesel generator (EDG) day tank check valve leak.

b.

Observations and Findin s Identification of Issue Condition Report (CR) 98-0491 identified a degraded condition of the "E" EDG day tank.

The day tank level was slowly decreasing, requiring periodic fuel oil addition.

The operability determination for CR 98-0491 was reviewed in NRC Inspection Report 50-387,388/98-01,se'ction 04.1.

During that review, the inspectors observed that the diesel day tanks were administratively controlled, by an SSES Technical Specification Interpretation (TSI), at a level significantly higher than specified by TS.

SSES Licensin Bc Desi n Basis TS 3.8.1.b.1 requires a diesel day tank minimum volume of 325 gallons of fuel for each diesel engine (e.g., the "A" thru "E" EDGs)

~ TS surveillance requirement 4.8.1.1

~ 2.a.1 requires the day tank fuel level to be verified in accordance with the frequency specified in TS Table 4.8.1.1.2-1 in order to demonstrate diesel operability.

The TS bases, in part, state the requirements for demonstrating operability are in accordance with Regulatory Guide (RG) 1.137, Fuel-Oil Systems for Standby Diesel Generators, revision 1, October, 1979.

RG

~ 137, in turn, endorses American National Standards Institute (ANSI) N195-1976, Fuel-Oil Systems for Standby Diesel-Generators.

The ANSI standard specifies a day tank minimum volume "sufficient to maintain at least 60 minutes of operation at the level where oil is automatically added to the day tank" (i.e., fuel oil transfer pump automatic start level-switch setpoint), at rated diesel load, plus a 10% margin.

FSAR section 9.5.4.1, Diesel Generator Fuel Oil Storage and Transfer System Design Basis, states the diesel fuel oil system design complies with ANSI N195-1976.

FSAR section 9.5.4.2, Diesel Generator Fuel Oil Storage and Transfer System - System Description, states "the day ta'nk [for each diesel] contains sufficient oil for over one hour continuous diesel generator operation at its

'ontinuous rated load." Therefore, the FSAR design requirements and commitments are consistent with the TS basi Summar of Modification to EDG Fuel Oil S stems In 1990, SSES performed modification 90-3009A-D to the, diesel fuel..oil systems to send excess fuel, bypassed from the mechanical fuel injection pumps, to the underground diesel fuel oil storage tanks, for the "A" through "D" diesels.

This modification did not apply to the "E" diesel

~ Prior to the modification, the excess fuel was effectively returned to the day tank through a fuel oil cooler.

This change removed the fuel oil coolers and re-routed the bypassed fuel to the fuel oil storage tanks.

As a result, the amount of fuel oil supplied to the diesel from the day tanks, to provide for a 60 minute diesel run (plus 10% margin), increased from 325 gallons to 424 gallons, per calculation M-DOS-006..ln June 1990, modification 90-3009A-D revised calculations M-DOS-006, EC-023-0512, EC-023-0513, EC-023-0514, and EC-023-0517 for the fuel oil transfer pump automatic start level-switch setpoints to ensure day tank minimum volume compliance with ANSI N195-1976. The level setting diagram J-653, sheet 48 was revised accordingly.

When the modification was completed for each EDG A-D fuel oil system, the fuel oil transfer pump automatic start level-switch setpoints were changed to assure 424 gallons remained in each diesel day tank at the point where the pump started.

Detailed Review of Modification and Identification of Nonconformin Condition Safety evaluation 90-3009, revision 1, dated May 24, 1990, stated the proposed action involved a revision to TS 3.8.1.1, in that "this modification changes the amount of fuel required to support the [ANSI] N195 requirement.,"

However, the safety evaluation failed to evaluate the change for the potential to reduce the margin of safety as defined in the TS,.bases.

Based on the diesel day tank minimum fuel oil volume of 325 gallons (i.e., as specified by TS 3.8.1.b.1), if the fuel oil transfer pump failed to start, then the diesel run time, after reaching the automatic start level-switch setpoint for the transfer pump, would only have provided approximately 45 minutes of diesel operation.

This would be a reduction in diesel run time of about 30%, from the 60 minutes, plus 10% margin, specified by the ANSI standard.

The TS basis states

"The surveillance requirements for demonstrating the OPERABILITYof the diesel generators are in accordance with the recommendations of...Regulatory Guide

~ 137." The RG 1.137 endorses ANSI standard N195-1976 which, in turn, specifies a minimum volume as providing 60 minutes of diesel operation, plus a 10% margin.

Therefore, the value for the day tank minimum volume is considered defined in the TS bases as the volume necessary to meet 60 minutes of diesel operation, plus a 10% margin.

This modification to the fuel oil system increased the fuel oil consumption rate from the day tank.

The inspector concluded that this change resulted in a reduction in a margin of safety as defined in the TS basis, because, after the modification, a volume of 325 gallons, as specified by the TS limiting conditions for operation (LCO) and verified by surveillance requirements, would no longer provide 60 minutes of diesel operation plus a 10% margin, as specified by the TS basis, but only provide approximately 45 minutes of diesel opera'tio After the safety evaluation had been approved by the Plant Operations Review Committee (PORC), PP&L subsequently determined. that prior NRC approval, for the

.change in day tank minimum volume, was not,required because. the. revised value (i.e., 424 gallons) would be greater than the minimum value (i.e., 325 gallons)

required by the current TS.

PP&L further concluded that since the facility change would not result in "violating current TS," administrative controls would be adequate until a change to the TS could be processed.

PP&L informed the NRC of this determination by PP&L letter PLA-3400, dated June 7, 1990, The licensee established Technical Specification Interpretation (TSI) 1(2)-90-004, revision 0, dated June 18, 1990, to ensure the diesel day tanks satisfied the intent of the TS basis.

The TSI, in part, stated "this interpretation shall remain in effect until an appropriate change to the Technical Specifications is approved."

The PP&L modification group prepared a TS Change Request TSCR-213, dated June 27, 1990, but PORC rejected TSCR-213, and ordered field testing, by actual diesel load runs, to verify acceptability of the day tank level switch setpoints.

The intention, as stated in the PORC Meeting Minutes, was not to cancel TSCR-213, but to delay TSCR-213 until after setpoint verification. However, TSCR-213 was never re-submitted to PORC.

In August 1990, after the modification was completed on the "A" and "C" EDGs, field testing determined that the ANSI requirements were not met, in that the day tank level switch setpoint only allowed 64 and 65 minutes, respectively, of diesel, operation, instead of greater than 66 minutes, as required.

PP&L initiated Non-

'onformance Report (NCR) 90-0173 to resolve the identified nonconforming condition for the "A" and "C" EDG day tank setpoints.

NCR 90-0173 performed an operability assessment and documented the disposition action to be taken as

"licensing department will evaluate the intent of the ANSI Standard N195-1976 and determine whether the current status of the [day) tanks is in adherence with this intent.

If not in compliance with the intent of the ANSI Standard, an exception to the Standard will be pursued."

Field testing results for the "D" EDG were satisfactory; no field testing results for the "B" EDG could be located.

In April 1991, engineering study SEA-ME-332 was performed in response to NRC concerns identified during an Emergency Diesel Safety Function Inspection (EDSFI),

to account for certain non-conservative factors in SSES day tank minimum volume calculations.

The study concluded the fuel oil transfer pump automatic start level-switch setpoints for the "A" thru "D" EDGs did not meet the ANSI requirements and would result in a diesel run time of 57 minutes, instead of greater than 60 minutes plus a 10% margin (i.e., 66 minutes).

The study further concluded the "E" EDG would also not meet. the requirements, unless a lower kW load (i.e., less than diesel

"rated" load, as specified by ANSI N-195), equal to that used for the "A" thru "D" EDGs, were used to calculate the fuel oil consumption rate (note: the "E" EDG has a higher rating than the "A"thru "D" EDGs).

The study identified that the nonconforming condition, previously identified by NCR 90-0173, applied to all five EDGs, PP&L initiated Engineering Discrepancy Report (EDR) G10082 to assess and resolve the identified conditio Based on the results of SEA-ME-332, TSI 1(2)-90-004 was revised, in July 1992, to require a day tank minimum volume to 461 gallons for the "A" through "D" diesels, and 528 gallons for the "E" diesel, be maintained in order. for the associated diesel to be operable.

However, the post modification fuel oil transfer pump automatic start level-switch setpoints were not changed, the switch setpoint calculations were not revised, and the level setting diagrams were not revised.

Although the TSI value for minimum volume had been revised, the actual day tank minimum volume,-

as established by the actual fuel oil transfer pump automatic start level-switch setpoint, remained unchanged at 424 gallons.

In November 1991, a second TS change, TSCR-236, was initiated to revise the TS day tank requirements to be consistent with the PPS.L calculation performed following the EDSFI. However, TSCR-236 was never approved by PORC, for reasons unknown.

In March and April 1992, PPSL closed out the EDR and NCR based on additional administrative controls which had been incorporated into plant procedures to require the day tanks to be "topped off" each time a diesel is operated.

The EDR and NCR disposition stated PP&L Nuclear Licensing had "evaluated the intent of the ANSI Standard" and determined that the action to top off the day tanks satisfied the criteria. This action allowed the nonconforming condition to remain in place, based on administrative controls (i.e., compensatory actions), without any further tracking mechanism or operability assessment.

The system design requirements, as specified in the FSAR and the TS basis were not revised, and the design documentation, such as calculations and level setting diagrams, were not revised.

In 1996, PPSL submitted an Improved Technical Specification (ITS) amendment (6-years after the modification) which proposed changes to the TSs regarding diesel day tank minimum fuel oil volume, to revise the day tank minimum volume requirement (i.e., change the TS bases) from 60 minutes of diesel operation, plus'a 10% margin, to "approximately 45 minutes of diesel operation."

Safet Si nificance of Nonconformin Condition Since the modification to the diesel fuel oil system increased the rate of fuel consumption from the day tanks, the time between LOW DAYTANK LEVEL alarm annunciation (e.g., a tank level indicating the transfer pump failed to automatically start) and emptying the day tank decreased from approximately 66 minutes to 56 minutes (contrary to the FSAR and TS basis).

This would reduce operator response time to recover day tank level, and prevent the loss of a running diesel generator, in the event a malfunction were to occur with the fuel oil transfer system from the storage tank.

The change in recovery probability, for the loss of a diesel generator caused by about a 10 minute reduction in day tank recovery time associated with this issue, is considered a negligible increase in the SSES probabilistic risk assessment (PRA) for core damag Re ulator Re uirements 10 CFR 50.59(a)(1), in part, states that a licensee may make changes to the facility without prior Commission approval unless the proposed change involves a change in the technical specifications or an unreviewed safety question (USQ)

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In 1990, Nuclear Department Instruction NDI-QA-9~ 1

~ 1, Safety Evaluations, implemented the programmatic requirement at SSES. -NDI-QA-9.1.1, in part, stated that PP&L must establish that a Technical Specification change is not required and that a USQ does not exist prior to implementing a plant change, or obtain NRC approval prior to implementation.

As of June 18, 1990, a change was made to the emergency diesel generator fuel oil system, which was evaluated by PP&L safety evaluation 90-3009, revision 1, dated May 24, 1990, as involving a change to TS 3.8.1.b.1.

In addition, PP&L failed to evaluate the potential of the change to reduce the margin of safety, as defined in the basis for TS 3/4.8.1, and therefore did not identify this portion of the modification as an USQ. This modification represented an USQ because at the technical specification diesel day tank minimum fuel oil volume of 325 gal, the emergency diesel generator run time would have been approximately 45 minutes rather than the 60 minutes, plus 10% margin specified in the TS basis.

PP&L did not obtain NRC approval prior to implementing the facility change and did not submit a license amendment to change the TS until 1996 (ITS submittal).

The failure to obtain prior NRC approval for a change that involved a USQ and to submit a TS change request prior to the facility change is considered a violation of 10 CFR 50.59 requirements.

This issue did not represent a significant USQ, because it involved an insignificant reduction of a margin of safety defined in a TS basis.

In addition, PP&L, although incorrect in its determination that prior NRC approval was not required, did inform the NRC by letter of its determination to perform the modification prior to submitting a TS change.

Therefore, this violation is not cited, based on the exercise of discretion in accordance with Section VII.B.6 of the Enforcement Policy (Violations Involving Special Circumstances).

(NCV 50-387, 388/98-08-01)

10 CFR.50, Appendix B, Criterion XVI, Corrective Action, requires, in part, that licensees establish. measures to assure that conditions adverse to quality, such as nonconformances are promptly identified and corrected.

As identified by the inspectors in June 1998, between August 1990 and June 30, 1998, PP&L failed to correct a nonconformance in the emergency diesel generator fuel oil transfer system.

Specifically, in August (990, in Non-Conformance Report 90-0173 and in April 1991, in PP&L engineering study SEA-ME-332, PP&L identified the fuel oil transfer pump automatic start level-switch setpoints in the emergency diesel generator day tanks did not meet the ANSI N195-1976 requirement, as specified in FSAR section 9.5.4.1 and TS Basis 3/4.8.1, to ensure a day tank minimum fuel oil volume sufficient for 60 minutes of operation'at the level where fuel oil is automatically added to the day tank, at rated load, plus a 10% margin.

The fuel oil transfer pump automatic start level-switch setpoints that existed in April 1991 were not changed to meet ANSI N195-1976 requirements.

This is example of a failure to

effect timely resolution of a nonconformance, and is considered a violation of 10 CFR 50 Appendix B, Criterion XVI, Corrective Action. (VIO 50-387,388/98-08-02)

c.

Conclusions In 1990, a PP&L safety evaluation for a facility modification concluded a Technical Specification (TS) revision was involved for a proposed change to the diesel day tank minimum volume. The safety evaluation failed to identify the proposed change as an unreviewed safety question.

PP&L did not obtain NRC approval prior to implementing the change and did not submit a TS change until 1996. This is considered a violation of 10 CFR 50.59 requirements.

However, this violation is not cited, based on the exercise of discretion in accordance with Section VII.B.6 of the Enforcement Policy.

In 1990 and 1991, PP&L identified the fuel oil transfer pump automatic start level-switch setpoints in the emergency diesel generator day tanks did not meet the American National Standards Institute (ANSI) requirement to ensure a day tank minimum fuel oil volume sufficient for 60 minutes of operation at the level where fuel oil is automatically added to the day tank, at rated load, plus a 10% margin.

PP&L documented this nonconforming condition in Nonconformance Report 90-0173 and engineering study SEA-ME-332, and implemented administrative controls, as compensatory measures, but failed to affect timely resolution.

The failure to effect timely resolution of this nonconformance is considered a violation of 10 CFR 50 Appendix B, Criterion XVI, Corrective Action.

V.'Mana ement Meetin s X1 Exit Meeting Summary The inspectors presented the inspection results, on the emergency diesel generator day tank minimum volume issues, to members of licensee management at an exit meeting on July 2, 1998. The licensee acknowledged the findings presented.

The licensee expressed a differing opinion on the 50.59 issues and the identified nonconforming condition, and presented a position that the items identified by the inspectors did not warrant issuance of a violation of NRC requirements.

The basis for the licensee's position was contained in an SSES report, "Evaluation of NRC Questions on Emergency Diesel Generator Fuel Oil Day Tanks" (see Attachment 2 of this report), and in PP&L Letter to NRC PLA-3400, dated June 7, 1990,

"Susquehanna Steam Electric Station Unreviewed Safety Question" (see Attachment 3 of this report).

The inspectors asked the licensee whether any materials examined during the inspection sho'uld be considered proprietary.

No proprietary information was identifie ATTACHMENT1 INSPECTION PROCEDURES USED IP 37551 Onsite Engineering Observations IP 62707 Maintenance Observations IP 71707 Plant Operations

~Oened 50-387,388/98-08-02 ITEMS OPENED, CLOSED, and DISCUSSED VIO Emergency Diesel Generator Day Tank Minimum Volume (section E2.1)

~Udated None.

Closed 50-387, 388/98-08-01 NCV Emergency Diesel Generator Day Tank 10 CFR 50.59 Review (section E2.1)

LIST OF ACRONYMS USED ANSI ASO CCF CFR CR DCP EDG EEI FSAR GL IN IR IPE ITS LCO LOCA LOOP NDAP NDI NOV NPO NRC NRR American National Standards Institute Auxiliary Systems Operator Common Cause Failure Code of Federal Regulations Condition Report Design Change Package Emergency Diesel Generator Escalated Enforcement Item Final Safety Analysis Report

[NRC] Generic Letter

[NRC] Information Notice

[NRC] Inspection Report Individual Plant Examination Improved Technical Specification Limiting Condition for Operation Loss of Coolant Accident Loss of Offsite Power Nuclear Department Administrative Procedure Nuclear Department Instruction Notice of Violation Nuclear Plant Operator Nuclear Regulatory Commission Office of Nuclear Reactor Regulation

Attachment

NSE OD PORC PRA RG SER SRO SS SSES STA TS TSI US USQ VIO WA Nuclear System Engineering Operability Determination Plant Operations Review Committee Probabilistic Risk Assessment

[NRC] Regulatory Guide Safety Evaluation Report Senior Reactor Operator Shift Supervisor Susquehanna Steam Electric Station Shift Technical Advisor Technical Specification Technical Specification Interpretation Unit Supervisor Unreviewed Safety Question Violation Work Authorization

ATTACHMENT 2 SVSQUEEA5NA. SES Z~ALUATrONOFNRC QVESXrOWS ON EMERGENCYDKSEX GENERATOR FUEL OILDAYTANKS Prepared:

R.R. Sgano Supervising Engineer - Nuclear Licensing Date Revimved:

Concurred:

J

. Kenny Supervisor - Nuclear Licensing Date

"7

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PZ R. A. Saccone Manager - Nuclear ModiQcations Date Approved:

G. D. Miler General Manager Nuclear Engineeang Date

PP&L EVAMATIONOF NRC QUESTIONS ON EMERGENCV DIESEL GENERATOR FUEL OILDAYTANKS Back ound Recently, the NRC Resident Inspectors have raised several issues relative to the Emergency Diesel Generator (EDG) fuel oil day tanks:

1. A 50.59 Safety Evaluation associated with several EDG modifications stated that the proposed action involved a change to the Technical Specification associated with the day tanks, but the modifications were implemented prior to submittal and receipt ofthe Tech Spec change.

The concern is that this action did not comply with 10CFR50.59, which requires NRC approval of a Tech Spec change prior to implementation of an associated proposed change to the facility.

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PP8Q. is implementing operating procedures that require the day tanks to be topped oF after each run in order to ensure that ANSI N195-1976 requirements are met, in accordance with the FSAR.

At issue is whether or not the standard requires this additiona1 volume after initiation of the fuel oil transfer pump subsequent to initial draindown of the day tank, when the additional volume aftorded by topping oF the tank would be unavailable.

3. In 1990, PP8cL established the need for changing the Tech Specs to reQect a corrected minimum volume requirement for the day tanks, but did not submit a proposed amendment correcting the error until submittal ofthe Improved Tech Specs in 1996. We have been asked why it took so long for us to request this change.

EDG Fuel Oil Stora

'e and Transfer S stem Overview Design Basis (PSAR 9.5.4. 1):

a)

Provides onsite storage and delivery offuel oil to the diesel generators for at least seven days of operation:

This provides emergency power to meet the load requirements for the engineered safety features followingloss ofoFsite power and a DBA.

b) Designed so that a single failure of any active component cannot affect the ability of the system to store and deliver fuel oil as required by design basis a) above.

c)

Designed to remain operable after a Safe Shutdown Earthquake.

The FSAR also states that "The design complies with ANSI Standard N195-1976."

Operational Basis (Tech Spec Bases 3/4.8. 1)

Relevant to this discussion is the statement that "The surveillance requirements for demonstrating the OPERABILITY of the diesel generators are in accordance with the recommendations of

~...Regulatory Guide 1.137 'Tuel-Oil Systems for Standby Diesel Generators",

Revision 1,

October 1979."

Description ofRelevant System Components (FSAR 9.5.4.2):

Fuel Oil Stora e Tanks:

Four 50,000 gal. storage tanks are provided for EDGs A, B, C, and D, and one 80,000 gal. storage tank is provided for EDG E. One storage tank is provided for each EGG, and each is sufficient for seven days full load continuous operation.

Each tank is buried underground adjacent to the building associated with the respective EGG.

e FuelOilTransferPum s: Onefuel oiltransferpumpisprovidedforeachstoragetank, and its design assures that at least seven days ofusable fuel &om each storage tank can be provided to the associated day tank. For EDGs A, 8, C, and D the puinp is a submersible design.

The E EDG has a horizontal, self-priming pump.

o Fuel Oil Da Tanks: EDG's A, 8, C, and 0 have a 550 gal. day tank; EDG E has a 650 gal.

day tank (these are tank volumes, not useable volumes).

Connections for filling, overflow return, recirculation, level instrumentation, venting, and emptying are provided. A manhole is provided on the tank for inspection.

The day tank contains fuel oil sufficient for over one hour continuous EDG operation at its continuous rated load.

Bach transfer pump takes suction from its storage tank and pumps the oil directly to the day tank.

Because the capacity ofthe transfer pump is greater than the fuel oil consumption of the engine, the pump can supply fuel oil to the diesel and simultaneously increase the inventory of the day tank. Por EDGs A, B, C, and D, the fuel oil transfer pumps age started and stopped automatically by day tank level switches.

For EDG E, the fuel oil transfer. pump is started and stopped automatically hy day tank level switches except when an emergency start signal is received.

In the emergency mode, the pump runs continuousl

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Evaluation Against Design Basis Criteria (PSAR 9.5.4.3)

a)

The total capacity of the storage and day tanks is sufficient for seven days of 4000 kW continuous operation.

This is sufficient for a DBAin one unit and a concurrent safe shutdown of the non-DBA unit.

%ithin this period, additional fuel could be delivered to the site as necessary.

b) There is physical redundancy of active components in the EDG fuel oil system.

An independent fuel oil supply train is provided for each EDG.

Each transfer pump is powered from the bus to which the BDG it serves is connected.

Pailure ofone pump or EDG willnot impact the operability of any component in another train.

Three EDGs are required during loss of offsite power and DBA conditions to meet the engineered safety feature load requirements.

The transfer pump discharge headers have a manually operated common connection line to permit fuel oil from one storage tank to be pumped to any EDG ifrequired.

Rupture of any portion of the transfer piping would impact the fuel oil supply of only one EDG.

c) The EDG fuel oil system is designed in accordance with Seismic Category I requirement Investi ation of Issues In order to determine the facts related to these questions, a chronology was developed. A discussion ofthe pertinent events follows.

In September, 1989, the NRC issued a Notice ofDeviation in Inspection Report 89-18 based on the PSAR statement that we had two hours of fuel in the day tanks, when in fact this did not reflect the useable amount. PAL responded in October 1989 in PLA-3265, with a commitment to revise the PSAR by July 1990. This change, LDCN 1629, was made in PSAR Rev. 42 in May, 1990.

I As an outfall oftwo EDG crankcase overpressurization events in September and October 1989, PPN. undertook numerous corrective actions; one was to control the intake air manifold temperature on each EDG in order to provide more consistent combustion.

The safety evaluation for this modification (90-3009) also addressed another modification for EDG's A, 8, C and D (the design of the E EDG already addressed the concern) that was directed at limiting the temperature ofthe fuel injection pumps at low load. The latter modification removed the fuel oil coolers, and rerouted the injection pump flowing vents on each EDG from the day tank to the underground storage tank.

Since this action reduced the fuel oil volume available for consumption in the day tank, the modification also proposed raising the fuel oil transfer pump initiation setpoint in order to ensure compliance with ANSI N195-1976, which states the following:

"Each diesel shall be equipped with day or integral tank or tanks whose capacity is sufficient to maintain at least 60 minutes of operation at the level where oil is automatically added to the day or integral tank or tanks.

This capacity shall be based on the fuel consumption at a load of 100% of the continuous rating of the diesel plus a minimum margin of 10%."

PPM. held a number of discussions regarding the intake air modification with the NRC in early 1990.

On April3, 1990, we transmitted a letter to NRC explaining that we were reviewing the modification as a potential unreviewed safety question due to the unavailability of "Q" control valves, and that it was our plan to use non-Q valves as an interim measure, given the safety importance ofimproving EDG reliability. A safety evaluation was developed for the modification; it concluded that the use ofthe non-Q valves was an unreviewed safety question.

In response to the question "Does the proposed action involve a change in a Technical Specification?",

the answer was marked yes, based on the recognition that Tech Spec 3/4.8.1.1 required at least 325 gallons of fuel oil in each EDG day tank, and the modification would create the need for 424 gallons.

The safety evaluation was reviewed by both PORC and SRC at the end of May, and approval was given by both committees to seek approval of the unreviewed safety question from the NRC.

The minutes of these meetings did not specifically address the Tech Spec change question, nor was a Tech Spec change package provided for review at these meetings.

Separate from this modification on the A - D EDG's, an Engineering Discrepancy Report (EDR)

600030 was written against the E EDG day tank capacity in the Tech Specs on June 1, 1990.

This EDR established that the E EDG required a di6erent capacity due to its higher outpu A request for NRC approval prior to implementation of the unreviewed safety question was transmitted on June 7, 1990 (PLA-3400). A Tech Spec change was not proposed at this time.

However, the June 7 letter included documentation ofPAL's determination that:

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the flowing vents modification on the A-D EDG's would result in an added drain on the day tank that would require a greater minimum volume in order to meet ANSI N195-1976 requirements,

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a Tech Spec change was being prepared, but was not required prior to implementation since Tech Specs would not be violated by the more conservative limit, and that this position had been reviewed with the NRC, the E EDG original design also required a higher Tech Spec limit, and

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administrative controls on all EDG day tank volumes would ensure compliance with the ANSI standard.

It specifically stated:

"Currently, thc niiiutnumvolume specified in the Tcchnical Specifications is not sufficient to suppott what willbe required as a result of the modification; accordingly, we are preparing a proposed change to thc Tcchnical Speci6cations.

However, the revised value, since it is greater than the minimum requirement, willnot violate the current Tcchnical Spccifications.

Our IOCFR50.59 review lias therefore determined that a Technical Speci6cation change prior to the modification is not required as long as we administratively control thc day tank volume to the value which we determine to mcct ANSI Nl95-l976. This position was reviewed with thc NRC Project Manager and the Sr. Resident Inspector, ifthe NRC has any questions on this determination, please contact us.

For your information, PPM. has determined that due to the higher output of the 8 diesel (the F. diesel already incorporates fiowingvents), it should also have a higher required minimum volume. In order to ensure that ANSI N195-1976 is met for thc 8 diesel, PP8Q. will implement administrative controls to cnsurc the larger minimum volume is met until a change to the Technical Specifications can be processed."

Subsequent to this communication, on June 18, 1990, PPAL documented a

Technical Specification Interpretation (TSI 1-90-004) for the E EDG that established administrative controls pending completion of a change to the Technical Specifications.

TSI controls for EDGs A, B, C and D were not provided because they were not needed: the flowing vent modification had not yet been performed.

On June 21, 1990, PPAL signed ofF an "ActionRequired" form documenting that procedures had been. changed to require "topping ofF'he day tank following diesel generator runs.

These changes were accomplished via PCAF's 1-90-0470, 0471, 0472, and 0473.

The reason for this action was documented as follows:

"Following review of PPM.'s response to Notice of Deviation, the NRC Resident Inspector has requested additional action (i.c., operators to "top o6" diesel generator fuel oil day tanks followingsuivcillancc tuns). Revise SO's and any other applicable procedures as neccssaty."

On June 28, 1990, a Technical Specification was proposed to PORC consistent with calculations (M-DOS-006, Rev. 1) that assumed implementation of the flowing vent mod for EDGs A, 8, C and D, and accounting for the higher output ofEDG E. The change was rejected by PORC (ref.

PLI-64842) until field testing could be performed to validate the Tech Spec numbe On August 14, 1990, the AEDG was field tested and the day tank setpoint was changed.

The run time of 63.52 minutes did not meet PP8cL's interpretation of the ANSI requirement (one hour plus ten percent margin = 66 minutes).

As a result, Non Conformance Report (NCR) 90-0173 was initiated.

On August 23, the TSI was revised to reflect the results of the A EDG field test, and calculations for the other (8 through E) EDGs.

The C and D tanks remained at 325 gallons

. since the drain modification had not yet been performed.

The TSI also noted that it would remain in diect until modification ofall EDGs was completed.

'On August 26, the C EDG was field tested.

The run time of 65.16 minutes did not meet the ANSI requirement; on October 3, 1990, the NCR was revised to include the C EDG. On October 11, 1990 the D EDG was field tested.

The run time of67.32 minutes met the ANSI requirement.

The day tank setpoints for the C and D EDG's were changed on August 28 and October 12, respectively.

The above field tests were performed subsequent to the flowing vents modification. Although the TSI was not r'evised right after the C and D mods/field tests, the existing action to top oK the tanks proceduralized in June 1990 remained in eFect, and it is believed that further changes to the TSI were awaiting disposition ofthe NCR on the A and C EDG field tests.

In April 1991, the NRC EDSH questioned the adequacy of the day tank calculation.

A calculation was performed (SEA-ME-332; later renamed as EC-024-0595) and confirmed that the ANSI requirement was not met based on the day tank setpoints.

EDR G10082 was written, and subsequently closed based on existing EDR 600030, which was tracking implementation of a proposed Technical Specification change.

In March and April 1992, respectively, EDR G00030'and NCR 90-0173 were closed based on the existing proceduralized action to top offthe day tanks.

The EDR closure states:

'The action to top offthe diesel day tank each time the diesel is operated at the conclusion ofoperation willsatisfy the oriteria ofhaving enougli fue) oil for at least on hour ofoperation (ANSI N)95-)976 requireinent) plus a 10%

margin."

The NCR disposition contains similar wording.

Another TS change (TS-236)

was initiated in November, 1991 to revise the day tank requirements consistent with the EDSFI calculations, This change was never approved beyond the originator. No documentation explaining why was located.

On July 30, 1992, following disposition ofall open deficiencies, the TSI was revised to reflect the requirements ofthe calculation performed in response to the EDSPI, and also included reference to the procedural requirement to top offthe day tanks after each.

The reference in the previous TSI revision to a need to change the Tech Specs was dropped at this time.

In 1993, TS 236 was still active and being tracked as the resolution to a Design Basis Document (DBD) Open Item (No. 40 in DBD 13 on the EDGs) involving compliance with ANSIN19 In October, 1993, PP&L began cost/benefit reviews of conversion to the Improved Technical Specifications, based on the September 1992 issuance of NUREG-1433.

Sometime after work began on ITS, 'a decision was made that TS 236 would be handled through the ITS submittal (this was documented in the DBD Open Items database during a complete re-review of these open items that occurred in early 1996 in response to industry CLB issues). The Rev. 0 proposed ITS amendment occurred on August 1, 1996; this submittal contained the-proposed revisions associated with the day tanks.

PP&:I. Position on Issues Issue I: A 50.59 Safe Evaluation associated with several EDG modifications stated that the ro osed action involved a chan e to the Technical S ecification associated with the da tanks but the modifications were im lemented rior to submittal and recei t ofthe Tech S ec ch n e.

The concern is that this action did not com l with 10CFR50.59 which re uires NRC a royal of aTechS ecchan e riortoim lementationofanassociated ro osedchan etothefacilit P~PRLPh

PB PP I

I I

I

.90.3009, I

I 303 d h<<h

9 d

fuel oil modification "involved" a change to the Technical Specifications. It did not document when or h'ow this change would be sought. PPK. determined that the Technical Specification.

~ change was not required prior to implementation of the modification'because the modification would not cause a. Tech Spec violation.

Administrative controls were developed and implemented, and a Tech Spec change was initiated.

This position was reviewed with key NRC personnel, and documented in a letter to the NRC prior to implementation ofthe modifications.

The letter specifically. stated, "ifthe NRC has,any questions on, this determination,, please. contact us.

Although PPM. recognizes our accountability for the determination, we believe that the record clearly demonstrates that substantial communications were held openly with the NRC on this issue at the time it occurred, and that our position was not challenged at that time.

Since the focus of 10CFR50.59 is to establish the need forNRC review prior to acting on a proposed change, PP&L believes that our actions met the intent ofthe regulations as they were viewed eight years ago.

In retrospect, although the record indicates PP&L's intent to pursue a Tech Spec change, the thinking that resulted in Rev. 2 of the TSI dropping statements refemng to the need for a Tech Spec change may have been the result of a debate over whether or not the change was really required.

The position may have been taken that the Tech Spec value should reQect only that volume which would be consumed by the engine over 66 minutes, since this is the regulatory basis ofthe requirement.

Any additional volume that would bypass the engine and return to the fuel oil storage tank could be accounted for in plant procedures, such that the consumption-based Tech Spec value was ultimately verified to be available.

Despite this interpretation, we have determined that we would not implement the same modification today without requesting a Tech Spec change from the NRC. Although we continue to believe that Tech, Spec changes that do not violate Tech Spec requirements can be implemented administratively in certain cases (e.g.,

an identified Tech Spec error),

we would not today

implement a modification that would create such a situation. We further believe that this occurred in 1990 only because of the perception of urgency associated with EDG reliability after the crankcase overpressurization events; and that it therefore represents an isolated event.

It is also important to point out in response to this issue that no evidence was found that PPdQ.

was trying to avoid making a required change.

The letter which was submitted:

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was associated with highly visible concerns on BDG reliability that were under substantial NRC scrutiny,

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included a request for prior NRC review and approval of another modification that was determined to be an unreviewed safety question, and dearly defined our position and documented that it had been reviewed with key NRC personnel.

Based on the above, PPAL does not believe that NRC issuance of a violation of 50.59 requirements is warranted.

Issue 2: PPEcL is im lementin o eratin rocedures that r uire the da tanks to be to ed off after each run in order to ensure that ANSI N195-1976 re uirements are met in accordance with the PSAR. At issue is whether or not the standard re uires this additional volume after initiation of he fuel oil transfer um subse uent to initial draindown ofthe d tank when the additional volume aForded b to in ofrthe tank would be unavailable.

9~99L:lh 9:9AN h

ld

.

'

ANdl N999-19 9,

9'

states:

"Bach diesel shall be equipped with day or integral tank or taiiks whose capacity is suQicient to maintain at least 60 minutes of operation at the level where oil is automatically added to the day or integral tank or tanks.

This capacity shall be based on the fuel consumption at a load of l00% of the continuous rating of the diesel pIus a minimum margin of 10%."

The standard can be viewed as a good design practice that ensures an hour's supply exists ifthe transfer pump is lost at any time over the seven day period.

It can also be viewed as a requirement to ensure that an hour's supply exists without dependence on the transfer pump for the initial phase ofa DBA, which is the way PPkL has considered it since it is monitored by the Tech Specs.

Prom a safety perspective, either is acceptable, since SSES is analyzed for the loss of one EDG.

However, since the issue concerns Tech Spec compliance, our position is that the administrative controls on day tank level to ensure the initial hour's supply meet the intent ofthe Standard as it applies to the Tech Spec surveillance. We believe that this interpretation was shared by the NRC Sr. Resident at the time, based on documentation indicating that in January 1990 he provided input to our decision to top off the tanks in order to ensure compliance with the standard.

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We recognize that the "good design practice" interpretation of the standard is not met by our administrative controls, and we interpret this to be a qualification issue as defined by Generic Letter 91-18 Rey.

1. PPM. proposed a Tech Spec change with the Improved Tech Specs that

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would obviate the need for interpretation by changing the one hour requirement to 45 minutes that has since been tabled based on the concerns being addressed herein.

However, after discussion with the EDG vendor, we have determined that an option exists to withdraw this change, and to modify the bypass fuel path on EDG's A, 8, C and D such that it returns to the day tank. In order to obviate further discussion on these issues, PPAL has decided to implement this modification during planned upcoming EDG outages.

Based on the above, PP8cL believes that our interpretation of the ANSI Standard is correct as it applies to the Tech Spec requirements on EDG day tank level, and that the EDG's have not been operated outside oftheir design basis as defined by 10CFR50.2.

We now recognize, however, that a non safety significant qualification issue has been identified regarding verbatim compliance with the ANSI standard and we are taking appropriate action to resolve it.

Issue 3:

Tn 1990 PPAL established the need for chan in the Tech S ecs to refiect a corrected

'minimum volume re uirement for the da tanks but did not submit a

ro osed amendment correctin the error until submittal of the Im roved Tech S ecs in 1996.

We have been asked wh it took solon forusto re uestthischan e.

2~322 2

. PPPb h

b bl b

h

6 hb 36.236 not pursued more vigorously after being originated in late 1991. We believe that it was originally paced by resolution of the related open deficiencies, and Rev, 2 of the TSI, but these were completed by mid-1992.

Subsequently, the DBD Program tracked TS-236 as an open item until a decision was made that the ITS Project would resolve the issue.

As stated in the response to

• Issue.1 above, it is plausible that an interpretation. occurred. that. the, additional volume required by.

the modification should be controlled by procedures rather than the Tech Specs, since it was not actually consumed by the EDG.

This would provide the missing rationale as to why Rev. 2 ofthe TSI discontinued tracking the need for a Tech Spec change.

Regardless, we do not believe that our actions on this item were timely, We do believe that the current CR program would ensure that a similar change today would be dispositioned on an acceptable schedul PP&L Position on Safet Si'ficance PP&L does not believe the issues that have been raised are safety significant for the following reasons:

1.

The safety design basis of the fuel oil system is to provide for seven days of operation under LOOP and DBAconditions including single failures ofactive components, and also to remain operable a&er a safe shutdown earthquake.

The capability ofthe system to do this was never in question.

2.

The one hour day tank requirement imposed by the standard through reference in the PSAR assures that one hour ofEDG operation is available ifthe transfer pump fhils. This provides defense in depth, but is bounded by the design assumption that one EDG willfail.-

3.

At the time the issue came up in 1990, diesel reliability was a very visible safety issue for both.

PML and the NRC due to EDG events that had occurred at SSES.

The modification in question was-viewed at the time as one ofa number ofsafety enhancements to the diesels.

-4.

The modiGcation in question was reviewed by two internal safety committees, and independently with the NRC both verbally and on the docket; clearly, no concerns were raised at the time.

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5.

Upon installation of.the modification, PPEcL assured compliance with the one hour requirement by imposing administrative controls on day..tank. level based on calculations that accounted for the impact of the modification.

These controls took the form of Tech Spec Interpretations (and Operating procedures)

that were controlled by Operations.

6. PAL subsequently performed non-required field testing and revised the administrative controls to account for the test results.

7.

The ANSI Standard requires ten percent margin under the assumption that the day tank volume required to support one hour of operation is based solely on calculations.

Since PPM. performed Geld testing, this ten percent represents additional safety margin that has been assumed, but should not be require References ontrol of day tank I. NRC Inspection Reports 50-387/89-18 and 50-38S/89-16, dated 9/1/89.

2.

PLA-3265 (Letter in response to Notice ofDeviation), dated 10/2/89.

3.

DCP Safety Evaluation No. 90-3009 Rev. 1, dated 5/25/90.

4.

PORC Meeting 90-060 Minutes (PLIS 35613) dated 7/3/90.

5.

SRC Meeting 90-3 Minutes dated May 90.

6.

EDR G00030 (E EDG day tank does not meet ANSI), o'riginated 6/1/90..

7.

PLA-3400 (Letter requesting review of USQ and documenting admin c level), dated 6/7/90.

8.

TSI 1/2-90-004, dated 6/1S/90.

9.

PCAP's 1-90-0470, 0471, 0472, and 0473.

10. Tech Spec change TS-213, dated 6/27/90.

11. PLI-64842, originated 8/9/90.

12. Test Control Documentation Sheet for TP-024-092 dated 8/14/90.

13. NCR 90-0173 (AEDG day tank doesn't meet ANSI) dated 8/14/90.

14. TSI 1/2-90-004 Rev. 1, dated 8/23/90.

15. PORC Meeting 90-078 Minutes (PLIS-35887) dated 8/29/90.

16. EDR G10082 (EDSPl), originated 4/12/91.

17. SEA-M-332, dated 4/2/91. (Renamed EC-024-0595).

lS. Tech Spec change TS-236, originated 11/13/91.

19. TSI 1/2-90-004 Rev. 2, dated 7/30/92.

20. EC-023-0507, dated 5/31/96.

21. PLA-4488, (Letter submitting proposed ITS amendment),

dated 8/1/96.

22. TSI 1/2-90-004 Rev. 4, dated 1/29/9S.

23. CR 98-1663, 5/12/98.

24. PSAR Rev. 52, Section 9.5.4.

25. ANSIN195-1976, "Fuel Oil Systems for Standby Diesel-Generators".