ML20112J680

Responds to NRC 960321 RAI Re Proposed Changes for EDG Aot. Preliminary Estimated Schedule for Activites Including EDG 24 Month Insp Encl

ML20112J680
Person / Time
Site:	Oyster Creek
Issue date:	06/13/1996
From:	Roche M GENERAL PUBLIC UTILITIES CORP.
To:	NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
References
6730-96-2138, NUDOCS 9606200389
Download: ML20112J680 (15)

Text

q

< J'.1 Nuclear

en: r e F

GPU Nuclear Corporation o

Forked River, New Jersey 08731-0388 609 971-4000 Writer's Direct Dial Number:

June 13,1996 6730-96-2138 U. S. Nuclear Regulatory Commission Attn: Document Control Desk Washington, DC 20555 Gentlemen:

Subject:

Request for Additional Information Related to Proposed Changes for Emergency Diesel Generator Allowed Outage Time GPU Nuclear has prepared the following responses to the NRC's request for additional information dated March 21,1996. To facilitate understanding, the questions have been reproduced to provide a context for the responses. The staff's questions are shown in italics.

1.

Provide details of scheduled periodic inspection with approximate time required andfrequency ofperforming each action. Also, provide total marimum time i

i required in the past to complete inspections and overhaul.

l A preliminary estimated schedule for activities included during an EDG 24 i

month inspection is attached (Attachment 1). This plan shov.s an approximate 5 day duration per diesel assuming wor',, ecurs as scheduled and no problems j

or unusual conditions are encountered. It also assumes two twelve hour shifts L

by contractor personnel. If this change is approved, GPU Nuclear would use in house personnel, probably on three eight hour shifts. GPU Nuclear is presently reviewing a series of variables which have the potential to lengthen the estimated period of performance.

200000 9606200389 960613 PDR ADOCK 05000219 P

PDR 0'

0 GPU Nuclear Corpo'ation is a sunscary of General Pubhc Utat,es Corporation

Some variables are as follows:

a.

Poor or failed battery or battery discharge test.

(Could add I to 7 dar, to present schedule).

b.

Potential engine <genntor realignment required (Could add 1 to 3 da.o to present schedule) c.

Control problem founc iuring restart testing (Could add 1 to 5 day; to pcesent schedule) d.

Potential degraded eugine wmponent identified (Could add 1 to 3 days to present schedule)

GPU Nuclear is also reviawi1g specific activit es of the 24 month i

surveillance in order to reduce the estimated overall duration to the minimum possible. However, contingency for events as dercribed above is required as most of these events have occurred during past su veillance periods. The previous several inspections occurred during plant shutdown periods with EDG out of service windows from 21 to 28 days per diesel. These out of service wii.daws were driven by significant EDG modiGcations and major engine component replacement. Since the modifications determined the length of EDG cut of servim time, this information does not provide useful data to determine time required for engine inspection alone. On one occasion, prior to the recent EDG modifications, the period of performance for surveillance alone was approximately 3 days (around the clock). Our procedures now include more comprehensive inspections making a general estimate of a 5 day duration (without contingencies) reasonable. Assuming one contingent event of average duration, the inspection duration would be 8 or 9 days. If another contingent event were to occur, or the replacement parts for the initial problem were not available on site, the period of performance would be funher extended.

2.

Because of the potential safety impact of the extended emergency diesel generator (EDG) allowed out-of-service time (AOT)forpreventive maintenance (PM), the staff believes inat the plant shculd have an uiternote ac (AAC) power source which can be substitutedfor the inoperable EDG. Additionally, certain compensatory measures are needed during the extended EDG AOT to assure safe operation of the plant. Provide a discussion of how you would address each condition listed below as related to Oyster Creek.

i

a. The technical specifications (TS) should include venfication that the required systents, subsystems, trains, components, and devices that depend on the remaining EDG as a source of emergency power are operable before remoGng an EDGfor 141 In addition, positive measures should be provided to precaude subsequent testing or maintenance activities on theses systems, l

su'> systems, trains, components, and devices while the EDG is inoperable.

2

Oyster Creek Technical Specification 3.0.B requires that when a normal power source or emergency power source is inoperable, any redundant system, component or device supported by the available power source must be operable. In addition, the Oyster Creek On Line Maintenance procedure provides positive measures in managing system outage windows. The response to question 6 outlines those positive measures.

b.

Before taking an EDG outfor an extended period to perform maintenance, the AAC source should be venfied: (1) that it is functional; (2) that the AACpower source is capable of being connected to the safety bus associated with the EDG to be taken out of service; and (3) that the AACpower source can be connected to the safety bus associated with the ineperable EDG once every shift thereafter.

At Oyster Creek, the Alternate AC (AAC) capability is provided by GENCO's combustion turbines (CT) located at the Forked River site. The system is configured such that only one of the two cts is required to supply power to Oyster Creek. The cts can be utilized to meet the requirements of 10 CFR 50.63. However, the AAC is not designed to be directly connected to the emergency AC power system under normal operating conditions. It would be available within one hour of an SBO event. Two breakers, one that is non-class 1E and one that is Class 1E separate the AAC supply from the 4160 engineered safeguards buses. The AAC source will not normally be connected to the preferred or on-site emergency power system. Thus, no single active failure or weather-related event will disable both on-site emergency power sources and simultaneously fail the AAC power source. The AAC system will not automatically load shutdown equipment on the ES bus; manual loading must be employed.

The AAC power source can be verified to be functional by checking the CT status indicating lights in the turbine building or the associated breakers and lights local to the cts.

i Voluntary entry into a limiting condition of operation (LCO) action c.

statement to perform PM should be contingent upon a determination l

that the decrease in plant safety is small enough and the level of risk is acceptablefor the _ period and is warranted by operational necessity, not by convenience.

Inspection of the diesels is prudent and in accord with vendor recommendation.

The responses to questions 4 and 5 provide PRA data concerning the impact on plant safety.

3

The bases of Oyster Creek TS 3.7, " Auxiliary Electrical Power," state that "the general objective is to assure an adequate supply of power with at least l

one active and one standby source of power available." The bases describe l

four active and two standby (EDG) sources of power excluding the plant's l

main generator. The bases also cite the probability analysis in Appendix L to Amendment 3 of the Oyster Creek FDSAR which is based on one diesel and j

shows that even with e diesel the probability of requiring engineered safety features at the sam <

" : as the second diesel fails is quite small (" the i

probability of having power available following a loss-of-coolant accident is

]

0.99999 or greater"). Since that analysis was performed, the reliability of the diesels has been enhanced, thus further reducing the probability of diesel failure.

If TSCR 230 is approved, EDG inspection could be done with the reactor on-line and with at least two (including one active and one standby) sources of power available. The minimum power requirement cited in the bases would, therefore, be met or exceeded.

The performance of the EDG inspection while the plant is on line may result in a net safety benefit. The On Line Maintenance process assures greater l

flexibility in planning and scheduling. Performing the inspection during the operating cycle would permit enhanced focus on the EDG inspection activity and increased configuration control, compared to plant shutdown. In addition, the performance of the inspected diesel can be expected to be enhanced for the t

l remainder of the cycle in which it is inspected. Furthermore, the availability of both diesels during plant shutdown would be increased, thereby reducing

)

shutdown risk.

d.

Voluntary entry into an LCO action statement should not be abused by repeated entry into and uitfrom the LCO.

l GPU Nuclear agrees that voluntary entry into an LCO action statement should not be abused by repeated entry into and exit from the LCO. The intent of TSCR 230 is to permit entry into an LCO once every two years per diesel for the periodic integrated inspection. As indicated in the response to question 1, l

GPU Nuclear does not expect to use the entire 14 day period, but rather employ part of it as a contingency. Having a diesel generator unavailable for a long period (or several shorter periods) is inconsistent with the various EDG 3

reliability and availabdity goals to which GPU Nuclear has committed.

e.

Removalfrom service of safety systems and important non-safety equipment, including offsite power sources, should be minimized during the outage of the EDGfor PM.

4

GPU Nuclear agrees that removal of such equipment from service during the EDG outage for PM should be minimized. The Oyster Creek On Line Maintenance Procedure considers this very issue. A detailed discussion is provided in the response to question 6.

f.

Component testing or maintenance that increases the likelihood of a plant transient should be avoided; plant operation should be stable during the EDG PM.

The Oyster Creek On Line Maintenance (OLM) Procedure provides a methodology for determining that component testing or maintenance is acceptable given a system outage. This methodology considers many factors such as reactivity management, PRA considerations and Maintenance Rule performance criteria. The response to question 6 describes the OLM process.

3 As stated in the February 22,1996, letterfrom the licensee, the purpose of the requested amendment is to allow an increased outage time during plant power l

operationforperforming EDG inspection and overhaul, which would include 1

disassembly of the EDG. The staffis concerned that disassembly of an EDG would subsequently require pre-operational testing of the EDG (such asfull load rejection tests) to be performedfollowing this maintenance while the plant is operating instead of during shutdown, which has been the past practice. In order to resolve this concern, thefollowing should be addressed:

l The inspection of engine internal components consists of non-invasive practices which do not have the potential to change engine operation or response. Minor adjustments which are made increase fuel efficiency, promote peak cylinder efficiency, and fine tune speed and synchronizing functions. In addition, all of the speed control and major engine control and response characteristics can be

(

and are checked thoroughly prior to connecting the generator to plant power buses. Therefore, any adverse conditions would be observed and corrected prior l

0 l

to plant exposure to such risk.

Oyster Creek diesel generators are supplied with EMD 645E4 20 cylinder engines. These are two cycle engines where the cylinder internal conddica (liner wear, ring wear, head clearance) can be visually inspected through the intake air ports with the piston rotated to the down stroke. In this manner, the engine does not require component disassembly for an internal inspection. Access handhole

)

covers exist at each cylinder for crankcase and air box access to internal j

components for inspection. The general activities of the inspection are to open filter and strainer assemblies, check the torque of major engine component bolting (not retorque - just a check) and general visual inspection of internals.

Previous cleaning of fuel injectors did require rocker arm disassembly to remove injectors. However, discussion with the service vendor has determined this 5

t activity is not required. Since there is a test for injector leak down and integrity with injectors in situ, our inspection will no longer involve injector removal or rocker arm disassembly.

l An appendix to the inspection procedure includes a full load rejection procedure if such is required. This test is not performed unless significant engine disassembly has occurred during repairs or component replacement. The routine inspection does not require disassembly and accordingly this test is usually not j

performed. However, we have experienced full load rejections on several occasions during surveillances over the years:

System grid disturbance caused 55 leading var trip Bad CT termiral caused false differential trip Loose PT primary fuse caused 55 leading var trip Bad pressure switch caused full load engine trip Other full load trips with the plant in operatic,n None of the historical full load rejection trips has ever affected plant operation nor caused an EDG overspeed condition.

a.

What would be the typical and worse-case voltage transients to the 4160-V safety buses as a result of afull-load rejection?

With the Main Generator on line (plant in operation), voltage at the 4160 volt buses is determined by the Main Generator Voltage Regulator (the amplidyne).

In fact, due to the system 230 kv design including an automatic static var controller in the Whiting substation, it is very difficult for Main Generator Megavar loading to make a significant change to 4160 volt bus voltage levels.

l Thus, the Main Generator represents a source of load or impedance forcing function greater than 250 times that of a parallel diesel generator. Although no specific transient voltage calculation for the plant has been made considering an EDG full load rejection, it is evident from experience that there has been ne observable impact to plant operation. Specifically, Main Generator voltage recordings (for EDG full load trips not associated with grid disturbance) showed no change or spike. Since the main generator automatic voltage regulator has a control range of + or - 10%, it may be inferred that any l

voltage transient to the 4160 volt bus was somewhat less than 10%.

l Considering the pickup point for 4160 volt bus Grid Undervoltage (UV) relays

(

(approximately -8%), the worst case voltage transient expected for an EDG full Icad rejection may only actuate a mom:ntary undervoltage alarm. Since the Grid UV trip functi;n is delayed for ten seconds and the transient considered is virtually instantancous, there is clearly no threat to plant operation. This worst case supposition has not been experienced in any full load rejection of the Diesel Generators to date.

6

b.

If afull-load rejection test is used to test the EDG governor after maintenance, what assurance would there be that an unsafe transient

\\

condition on the safety bus (i.e., load swing or voltage transient) due to improperly performed maintenance or repair of a governor would not occur?

There is no maintenance performed to internal parts of the governor.

This inspection involves only a change of oil in the governor actuator. As discussed previously, the governor adjustments and response are checked prior to placing the EDG in parallel with the system in accordance with Woodward vendor instructions. If for any reason speed control falters while on line, the EDG (and plant) are protected by a 67 reverse power trip. On a couple of past events, the reverse power trip has occurred with equal lack of impact to plant operation. Again, this response is expected since the grid and Main Generator determine the 60HZ frequency of the grid with the EDG incapable of changing it.

c.

Using maintenance and testing experience on the EDG, identify possible transient conditions caused by improperly performed maintenance on the EDG governor and voltage regulator. Predict the electrical system response to these transients.

Possible maintenance induced governor umsients:

1.

No or low governor oil level - would cause overspeed trip or extremely slow response of governor on starting. Would be observed prior to parallel with system.

2.

Too high governor cil level - causes fast oscillations at fuel control rods generating thick smoke emissions. Probably could not be autosynchronized but if it did there would be fast oscillation of load (500 kw range).

3.

Fuel Control Rod binding - could manifest itself at any fueling i

point (high/ low speed - high/ low load). Could be observed as poor response off line, inability to synchronize or incapable of reaching normal load.

Spurious load changes on line are possible but such load changes would not influence plant operation.

4.

Incorrect Speed Adjustments or load limit -such variations l

would nearly all be observed in tests prior to synchronizing the l

EDG. Load limit misadjustment would be observed as inability to reach rated load (non-transient condition).

Other potential governor failures (non-Maintenance induced), considering the EDG is parallel to the system, would be low fuel signal level which will cause a reverse power trip or high fuel signal level which should be restricted from excessive overloads by the governor load limit (mechanical), the baseload 7

setpoint (electric) or the high load limit (electric). Load is not expected to dse abw. 7950 kw (4 HR rating of diesel).

The voltage regulator is a Magnetic Amplifier / Static Exciter with simple passive components. No mainicuame is required for these components other than cleaning. Possible problems induced by maintenance include simple disturbance of wire connections or open fuses. The impact of voltage regulator problems are swiftly recognized in testing prior to placing the generator on line. If for any reason the generator is synchronized to the line with a voltage problem or developed the problem after breaker closure, either a 47 Gen undervoltage or 55 leading vars protctive relay would trip and separate the generator from the plant power buses. The worst case transient could be no greater than and probably less than a full load rejection transient discussed earlier.

The licensee shouldprovidejustification ofperforming other tests if required, at power.

The only other test that might be required of an EDG if significant engine maintenance was performed (such as replacement of a power cylinder assembly) would be a 24 hour2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> load run test. This test is not usually performed since the inspection does not intrude on such engine components. This test was performed on DG-1 in 1988 when all power assemblies were replaced with new units and for DG-2 in 1991 when power assemblies were replaced. This test does not produce any unusual transients by itself and the worst occurrence would be a full load rejection if the test failed with consequences as discussed.

4.

Provide the current calculated total core damagefrequency (CDF) resulting from allprobabilistic safety assessment (PSA) sequences involving station blackout (SBO). Also provide the calculated total CDFfrom all SBO sequences after accountingfor the increase in EDG unavailability due to the ettended allowed outage time requested. Provide the instantaneous change in the CDF valuefor the worst-case plant configuration allowed under the proposed Specification. Erplain how the EDG PM and subsequent on-line operability testing is treated in the CDF calculation.

In the initial Technical Specification Change Request, a relative percent difference in core damage frequency (CDF) of 3.85 % was reported. This relative percent difference in CDF was the result of the evaluation of a modified Oyster Creek Probabilistic Risk Assessment (OCPRA) model l

evaluated using two different allowed outage time (AOT) options. The l

modified model and the AOT cptions are discussed in the paragraph below.

8

The modified OCPRA model was developed by removing conservative assumptions associated with offsite power recovery and average maintenance contributions of other systems. The modified risk model was termed EDGAOT. The EDGAOT model was quantified using two different AOT options. In the first AOT option, the original EDG unavailability (historical EDG out of service time) was replaced with an EDG unavailability equal to an AOT of 7 days for each EDG. In the second AOT option, the original unavailability was replaced with an unavailability equal to an AOT of 7 days for one EDG and 14 days for the remaining EDG. Both evaluations assume a single entry into the limiting condition for operation (LCO) for the full AOT period each year. In this manner, the relative risk of the two AOT options could be compared.

The result of the EDGAOT model was the CDF change of 3.85% reported in the original technical specification change request. The "EDGAOT" column on the table below provides the results on the two options including a percent difference between the " Total CDF" of the two AOT options.

Two sensitivity studies comparing the relative risk of the two AOT options, were performed using two different risk models. The first sensitivity study (Case 1) used the OCPRA (IPE) without any modifications and was quantified using the two AOT options described above. The second sensitivity study (Case 2) evaluated the NOM AINT risk model (OCPRA risk model with average maintenance terms removed) but without any modification to the offsite power recovery. This model was quantified using the same AOT options as in Case 1. For each sensitivity case, the percent difference of the two AOT options is presented in the table below. In addition, the SBO CDF requested in Question 4 is provided.

I l

l 1GCPRA EDGAOT CASE 1 CASE 2 Model P.esult IPE 7 days 7 & 14 7 days 7 & 14 7 days 7 & 14 Model per EDG days Per EDG days per EDG days Total CDF 3.76E-6 3.0E-6 3.2E-6 4.8E-6 5.1E-6 4.4E-6 4.7E-6 Total CDF n/a 3.85%

6.0%

6.5%

% Difference' SBO CDF 1.33 E-6 6.9E-7 7.6E-7 1.6E-6 1.9E-6 1.6E-6 1.8E-6

' The "% Difference" row provides the percent difference between the 7 days per dicsci and 7 and 14 day AOTs.

9

1 l

The CDF for the worst case configuration is not practical to calculate due to the number of potential combinations of safety or tech spec systems as well as non-safety or non-tech spec systems which could be out of service during the diesel generator inspection. However, the Oyster Creek Risk Management of On-Line Maintenance Procedure (2000-ADM-3022.01) provides guidance that a detailed analysis is required for those plant configurations which increase risk greater than a factor of 10, i.e., a Risk Achievement Worth (RAW) of greater than 10. This effectively controls risk below this level except in rare cases

)

where detailed analysis of the configuration is performed including potential mitigative / corrective actions. The instantaneous change in CDF (RAW) for an EDG out of service (OCPRA, IPE model) is approximately 6.3.

l Other, non-inspection related PMs and on-line operability testing were not included in the evaluation. This evaluation attempted to compare only the relative risk associated with the two AOT options. Historical PM history (EDG unavailability) is addressed in Question 5.

In order to more adequately respond to Question 4, additional risk model evaluations have been performed. The following evaluations provide a comparison of the absolute CDF increase due to the proposed technical specification change. This is in contrast to the relative risk comparison of AOT options provided above.

In the first evaluation, the base OCPRA (IPE) has been adjusted with a less conservative loss of offsite power recovery. The evaluation results including l

Total CDF and SBO CDF are presented in the table below under the column "

OCPRA (Revised LOSP Recovery)." In the second evaluation, the same risk model (OCPRA with a revised loss of offsite power recovery) was evaluated with the actual EDG out of service time and an additional 14 days out of service time on one EDG representing the proposed AOT. The results of that evaluation are presented in the table below under the column " AOT-14 (Revised LOSP Recovery and 14 Day EDG AOT)."

Average maintenance terms are included as is the EDG unavailthlity due to other, non-inspection related PMs and on-line operability testing. The instantaneous change in CDF (RAW) for an EDG out of service in t : AOT-14 model (OCPRA, with a revised loss of power recovery model and EDG AOT of 14 days).is approximately 4.5.

l l

l l

10 i

~-

Model OCPRA AOT-14 Result (Revised LOSP Recovery)

(Revised LOSP Recovery and 14 Day EDG AOT)

Total CDF 3.05E-6 3.31 E-6 Total CDF 7.85 %

Percent Difference!

SBO CDF 6.33 E-7 7.95E-7

' The " percent difrerence" row provides the percent difTerence between the " Total CDF" of the OCPRA and AOT.14 models.

Finally, a sensitivity case which evaluated the percent difference in total CDF if the base OCPRA (IPE) was not modified with a new less conservative loss of offsite power recovery. The base OCPRA (IPE) was compared with an evaluation of the OCPRA with the 14 day AOT added to the historical EDG unavailability of one EDG. The result was a total core damage frequency percent difference of 15.5 %. This value is considered extremely conservative and is not a useful comparison. It is provided for information only.

It should be noted that actions taken in the On-Line Maintenance Program will provide additional assurance that the remaining EDG as well as the combustion turbines are available during the EDG inspection period. Heightened awareness of the EDG maintenance will also reduce the risk associated with the activity.

5.

Provide the valuesfor the EDG reliability and availability values used in the PSA analysis to calculate the SBO CDF values requested in Question 4 above.

Discuss these values in relationship to any goals associated with the imp lementation of the maintenance rule and in comparison to actualpast performance of the EDG's at the plant. Also compare the values used in the i

PSA analysis to the target values committed tofor SBO.

The EDG reliability mean values used in the PSA analysis are EDG start failure, EDG Run failure (first hour of operation) and EDG run failure for remaining mission time. These values are 1.35x10 2,1.42x10-2 and 2.51x10 per hour for a total eight (8) hour mission. The EDG mean unavailability data used in the PSA model is given as a frequency of 6.15x10" and a duration of 1.26x10+'. This equates to an annual availability of 99.2% or 68 hours7.87037e-4 days <br />0.0189 hours <br />1.124339e-4 weeks <br />2.5874e-5 months <br /> per j

year out of service time per EDG. All data is plant specific over the time j

period from 1978 to 1988. The diesel generator availability data agrees closely with current data (January 1993 to May 1995) collected in support of the 11

n l

mamtenance rule (79.5 hour5.787037e-5 days <br />0.00139 hours <br />8.267196e-6 weeks <br />1.9025e-6 months <br /> out of service per year per EDG). Maintenance rule performance criteria goals have yet to be determined for the emergency diesel generators.

6.

The condition of offsite sources of electricalpowerprior to and during the i

extended EDG outage time have additionalimportance. Discuss what considerations should be given to not performing the extended maintenance when the ofsite grid condition or configuration is degraded or when adverse or extreme weather conditions (e.g., high winds, lightning, icing conditions) are expected. Discuss howplanning of the ettended EDG maintenance should consider the time needed to complete the extended EDG maintenance and the ability to accuratelyforecast weather conditions that are conditions that are erpected to occur during the maintenance. Discuss what, if any contingency plans should be developed to restore the inoperable EDG in the event of unanticipated adverse weather or degraded grid conditions occurring which can sigmficantly increase the probability oflosing ofsite electricalpower.

Oyster Creek utilizes guidelines for managing risk associated with all on-line equipment outages, including the Emergency Diesel Generator (EDG) outages.

This review involves the following departments: scheduling, planning, l

engineering, and plant operations. The 12-week system window sche.dule preparation and review process ensures that the risk is acceptable as determined I

by the Oyster Creek Probabilistic Risk Assessment (PRA) and performs additional PRA reviews as warranted by the risk analysis and its postulated core damage frequency (CDF). The risk for each system is determined by calculating the CDF for each system while the system function is disabled.

l This value is then compared to a base line risk calculated with the system l

function available to determine the percent increase in CDF. A PRA review of l

scheduled system windows is required whenever previously unanalyzed system j

windows occur concurrently. In the case of an EDG out of service window, all other systems including those impacting electric power distribution, offsite power buses and SBO windows, are analyzed using PRA for their respective impact.

During the 2 week period prior to the work week, a licensed Senior Reactor l

Operator (SRO) reviews the schedule for the system window identifying potential concerns and restrictions as relating to numerous issues which include the following: unexpected environmental considerations, required plant status, and any degraded p' ant conditions. Possible unexpected environmental concerns would include forest fires in the area, high winds, ice conditions, flooding, unstable grid conditions, hurricane watch, c.r tornado watch. The judgment of Operations Management would determine whether to proceed with the system window given the above considerations.

12 m

When in the system window, Operations Management evaluates the plant status and possible environmental concerns on a daily basis. If conditions warrant, the immediate exit from the system window could be directed. If that decision were made, the EDG could be made available for emergency standby readiness within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />. This time allows for sufficient battery charge for reliable EDG starting and control if required to exit the window when in the process of performing the EDG battery capacity test. This time is also sufficient to exit the mechanical inspection surveillance; restore all fluids to the engine, restore all filters, and perform necessary tests.

7.

The staff does not agree with the licensee'sjustification of deleting the phrase "in any 30 day period "from the existing specification. Standard Technical Specifications (STS) does not allow reactor operation with only one EDG availablefor 7 days. So to be consistent with the STS, the TS should be revised to "The reactor may remain in operatia& a period not to exceed 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> if a diesel generator is out of service. " Otherwise, the licensee needs to address safety implications, compensatory measures etc. in order to delete the phrase "in any 30 day period. "

GPU Nuclear believes that the phrase "in any 30 day period" is unnecessarily restrictive and not included in other L.CO action statements in the Oyster Creek TS. The history of the phrase is unclear but may be related to concerns about repeated entry into LCOs. As indicated in the response to question 2. d, GPU Nuclear has made commitments regarding EDG reliability and availability, multiple entries into the EDG LCO would be detrimental to attaining those goals. It is true that the STS allow operation not to exceed 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> with a l

diesel out of service. It is also true that there are no further constraints such as those imposed by the phrase "in any 30 day period." GPU Nuclear believes l

that the phrase is simply not required and should be deleted.

l l

l 8.

It appears that surveillance requirements 4.7A.5 and 4.7A.6 can be performed i

during power operation without declaring the associated EDG inoperable.

l Clarfy yourposition.

l Sun'eillance requirements 4.7.A.5 (full battery capacity discharge test) requires the charger and all other control loads be separated for test performance. Since 450 Amp hours are removed from a 450 amp hour battery during the test, we 2

could not meet Tech Spec. sections 4.7b.1.B.1.b,c or d for the Diesel battery until the battery was recharged and restored to an operable status. Therefore this test requires the EDG to be in an LCO or declared inoperable.

Surveillance requirement 4.7. A.6 is a battery service test which simply monitors a normal start of an EDG (worst case service profile). This test is specifically scheduled when the diesel is operable.

i 13

9.

Is there any plan to convert Oyster Creek TS to revised STSformat? If so, provide a schedulefor such a conversion.

GPU Nuclear has previously indicated that it does not intend to convert the Oyster Creek TS to the revised STS format.

10.

The licensee indicated that this amendment is a Cost Beneficial Licensing Action (CBlA). A saving of more than $100K will be realized. Is this sasing for the hfe of the plant?

Yes. If the amendment is issued, savings will be realized for each outage through the end of the license. The savings will accrue through the use of in house staff as opposed to contractor personnel. The scheduling of system outage windows during plant shut down will be less complex and outage duration may be reduced. In addition, there will be a reduced need for electrical cross ties during outages.

l GPU Nuclear believes that the responses above provide the staff with the information required to disposition TSCR 230. Should any additional information be required please contact Mr. Dennis Kelly at (201) 316-7885.

\\

Sincerely, j

l 0

4 l

Michael B. Roche i

Vice President and Director, Oyster Creek DK/ pip c:

Administrator, NRC Region I NRC Senior Resident Inspector, Oyster Creek Oyster Creek NRC Project Manager 4

14

PRELIMINARY EDG 24 MONTH SURV SCHEDULE DAY l

DAY 2 DAY 3 DAY 4 DAY 5 U

1 SH 2 SH I SH 2 SH I SH 2 SH I SH 2 SH I SH 2 SH INSTRUMENT CALIBRATIONS (PULL. BENCH CAL.. REINSTALL)

TURNOVER OPERABILITY SURV.

(APPROX.3 SHIFTS)

HANDW3LE DRAIN GOV.

CHANGE TURBO LOUVER LU3E ICOVER OFFl I

L.O.

_1 IFAN BELTSI I INSPECT. I I& INSPECT.i EDG OCS STARTS DRAIN WATER REPLACE ADO NEW CHECK INJECTOR ADJ. INJECTOR CRANK CASE INJECTOR SPD./ LOAD (2 HR)

GASK. SEALS GOV. OIL RLBBER lOSE LEAK TEST ALVE LASH FINAL DEPECT.

TIMING ADJ.

CW. INTERN.

y If DRAIN DAY CLEAN ROLL THM) UGH RAMPUP TAGOUT TANK L.O..F.O.

INSTALL NEW PERFORM TOROUE CYL. LIER REFILL IDLE SYNCHRO 3-0 DAYS

"(PROC.341-2tR)

STRAIERS L.O..F.O.

FAN CK CKS CHECKS INSPECTION (WATER SYSTEM INSPECT.

ADJ.

FILTERS DRAIN ji ILLLUBEj TEMP.LGTS SET,,UP,t L.D., PULL FILTERS CLEAN "Y" REMOVE.CLE CECK MAG.

VISUAL TAD CLEAR.

OVERSP.

FULL L I-2 SH.

I HR ' CLEAN FILT.

STRAINERS ENG. AIR PICKUPS INSPECT.

CKCKS DIL SYSTEM TEST INSPECT.

HOUSINGS FILTER b OIL PAN iCRANKCASEj lAUX.PU@Sj lC1.EAN EDUCTORJ iCLEAN DERTIAli i AIR BOX j i P TUBES L j TUBE (SCREEN) AIR FILTER DRAIN CE CK PISTON COOL.

PRESS.

IN OPERATION DETECTOR BATT. BATT.p EO,FLOATE BATT. FLOAT DISCH.1EST RECHARGE BATTERY i

3 OAY '2 DAY' (CONTINJED)

( 12 m) 2-3 DAYS N

BATT.LV. ANN.

ELEC. METER CAL.CWCK I

CAL I

BEGIN DISCH. TEST-BACKSHIFT IST DAY CLOSE PULL START CK CK GEN.

CHK. CONTROL CHECK ANN.

INSPECT.

TEMP LIFT STARTER GOV.

MOTORS O DOWN COPeECTIONS

+ BYPASS OF GEN.

TAGS

/ VOLT ADJUST. \\

BOLTS

t. CLEAN CIRCUITS j

RESTORE 3

~

MEGGER CHECK PT/CT MEGGER AUX.

FUNC. TESTS RE.MEGGER CHARGE ELEC. OPERATE OPS OPERATE y

c GEN./ ROTOR CONNECTIONS MOTORS /STRTR.

LOUVERS &

GEN./ ROTOR AC POWER EDG.

EDG.

g TRANSF. PUMP cy INSPECT CLEAN GEN.

CLEAN F.O.

REFILL REINSTALL CWCK

+3 GEN. BEAR.

INSULATION SW. CONTACTS DAY TAPE START MOTORS MOTOR g'

CURRENTS i

+

RELAY RELAY PROTECTIVE RELAY (PULL RELAYS FOR BENCH CALIBRATIONS)j i

TRIP i

l LOAD i

CALIBRATIONS CHECKS CHECKS

-