ML20099G302
| ML20099G302 | |
| Person / Time | |
|---|---|
| Site: | Seabrook  |
| Issue date: | 08/10/1992 |
| From: | Office of Nuclear Reactor Regulation |
| To: | |
| Shared Package | |
| ML20099G299 | List: |
| References | |
| NUDOCS 9208140195 | |
| Download: ML20099G302 (11) | |
Text
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SAFETY EVALUATION BY THE OFFICE OF NVCLEAR REACTOR REGULATIO_B EP.20EIJf1G AMENDMENT N0. 12 TO FACilllY OPERATING llCENSE NO. NPF-86 NORTB ATLANTIC MERGY SERVICE CORPORATION SEABROOK STATION. UNIT NO. 1 DDE ET N0. 50-445
1.0 INTRODUCTION
By letter dated fiarch 20, 1992, es supplemented on June 19, 1992, the Public Service Company of New Hampshire (former licensee) submitted a request for changes to the Seabrook Station, Technical Specifications (TS).
Pursuant to an order authorizing transfer of the facility, North Atlantic Energy Service Corporation,is now the licensed operator of Seabrook.
The June 19, 1992, letter provided clarifying information in response to NRC staff's request for additional information and was renoticed in the Federal Register on July 8, 1992 (57 FR 30256) with a nc.4 evaluation of no significt.nt hazards considerations.
The requested changes would eliminate the Resistance Temperature Detection (RID) Bypass Manifold System, which is currently used for the menurement of narrow range Reactor Coolant System hot leg and cold leg temperature, and replace it with direct immersion RTDs.
This modification affects the reactor protection system setpoints and uncertainties for RCS flow and T-avarage because of the different response time characteristics and instrumentation uncertainties associated with the new thermowell mountea RTDs.
The T-Average and Delta-T signal input arrangement to the reactor protection and control system is also modified, Accordingly, this amendment requires a revision of the Seabrook Station Technical Specifications for Overtemperature Delta T, Overpower Delta T, Reactor Coolant flow, and departure from nucleate boiling (DNB) parsmeters.
The requirements for verification nf RTD bypass loop flow are deleted.
Yi. 3 requirements for the performance of a precision heat balance calculation for determining the Reactor Coolant System flow rate are modified by increasing the thermal power level at which the heat balance is required.
The submittal proposed to change the power level below which the heat balance must be done from the current requirement of 75% of rated thermal power to 95% of rated thermal power, consistent with the Westinghouse recommendation to perform the heat ba'nce above 90% of rated thermal power.
9208140195 920010 DR ADOCK 0500 3
1.- 2.0 EVALVATION 2.1 Instrumeq1.ation and Cpatrol Issuet Instrumentation and control issues are reviewed in Section 2.1 below, and rector systems issues are reviewed in Section 2.2 2.1 Current Systs The present reactor coolant temperature measurement system uses coolant scoops in the primary coolant to diver t a portion of the reactor coolant into bypass loops.
The RTDs for T-hot and T-cold temperature measurement are located in the bypass loop manifolds and are ir<arted directly.into the reactor coolant bypass flow without thermowells.
Separate hot leg and cold leg bypass loops F
are provided for each reactor coolant loop such that individual T-hot and T-cold loop temperature signals can be developed for use by the reactor protection and plant control system.
~
Bypass pipjng form the hot leg side of each steam generator is used for the T-hot RTDs. Additional bypass piping from the cold leg side of the reactor coolant pump is used for the T-cold R10.
Botn T-hot and T-cold manifolds empty through a common header to the intermediate leg between the steam generator and reactor coolant pump.
Flow for each T-hot bypass loop is provided by three coolant scoops located at 120 degree intervals around the hot leg piping.
Beccuse temperature streaming in the cold leg is limited by the mixing action of the reactor coolant pump only one.sceop connection is installed for bypass flow to the T-cold bypass manifold.
The bypass manifold system was designed to resolve concerns with temperature streaming (temperature gradients) within the hot lag primary coolant.
The teriperature streaming experienced in the hot leg piping is a result of the reactor coolant leaving various regions of the reactor core at different temperatures.
The bypass manifold system compensates for the temperature streaming by mixing the primary coolant within the bypass manifold.
The bypass manifold system also limits high velocity coolant flow to the RTDs and allows RTD replacement without the need to draindown the reactor coolant system.
The output from the 'oypass loop RTDs provides tht. signals necessary to calculate the arithmetic average loop temperature (T-average) and the loop differential temperature (Delta-T).
The 1-4verage and Delta-T signals are then input to the reactor protection system.
The T-average and Delta-T signals for the plant control / computer systems are derived from the same set of protection system RTDs and T-average-and Delta-T calculations.
The T-average and Delta-T values are provided to the plant contrel/ computer systems through isolation devices, i
h The licensee states that the current system has caused plant shutdowns due to primary leakage througn valves or flanges, knd the intstruption of bypass flow due to valve stem failure.
Additionally, the licensee stated that the bypass piping contributes to increased radiation exposure to personnel when maiatenance is performed in bypass manifold system areas.
2.1.2 hG0Jed SYME 9 The modified system hot leg temperature measurement for each loop will be abtained using three fast response, narrow range, dual element RTDs mounted in thermowells. One element of each RTD will be utilized as a spare.
Two of the hot leg R10s will be mounted in thermowells within toe existing bypass manifold 4 coup penetrations.
Each bypass scoop will be modified such that reactar coolant will flow in through the existing holes of the bypass scoop past the RTD/thermowell assembly and out through a new hole machined in the bypass scoop.
Because of s luctural interference a new penetration will be in;taGed to accomcdate the third RID /thermowell assembly.
The modified RTD arral.gement will perform the same sampilng/ temperature averaging function as the original bypass manifold system.
The modified location for the third RTD in each loop has been evaluated by the licensee and the revised streaming uncertainties applied to the setpoint calculations.
Tite cold leg temperature measurerhents will be obtained by one fast response, nerrcw range, dual element RTD located at the discharge of the reactor coolant pump.
This RTD will be mounted in a thermowell within the existing cold leg bypass manifold penetration.
Because of the mixing actien of the reactur coolant pump, temperature gradients in the cold leg are minimized and only one R10 is used far cold leg temperature measurement.
Although cold leg streaming is minimi?.ed.by RCP raidn uncertainty calculations.g a cold leg streaming bias is incorporated into the As in the hot leg, the bypass manifold penetration will be modified to secept the RTD thermowell.
The licensee will replace the bypass manifold direct immersion RTDs with Weed Instrument Company Inc. dual element RTDs mounted in thermewells.
The spare element of each RTD will be terminated at the 7300 rack input terminals in the control room. This arrangement is intended to allow on-line accessibility to the RTD spare elciments in the event of an RTD failure.
The licensee states that the new thermowell mounted RTDs have a respnuse time equal to the time of the old bypass piping transport, thermal lag and direct immersion RTDs (about 4 seconds). lhe 4-secund response time of the Weed RTD thermowell assembly is suppnrted by industry experience, The 2-second electronics delay specified by the licenste is identical to the value for the RTD bypass system.
The licensee concluded that the safety analysis value of 6-seconds remains valid. noting that the 2-second electronic delay is conservative and provides soue margin.
The RTD manufacturer will perform response time testing of each RTD and thermnwell prior to installation to ensure the RTD/thermnell response time is bounded by the safety analysis value. The. licensee will also verify the response time of the new RTDs using loop current step respnose (LCSR) methodology following installation in the plant.
N To accomplish the hot leg temperature function previously done by the bypass manifold system, the modified hot leg RTD temperature signals (three per loop) will be electronically averaged in the protection system.
The averaged T-hot signal will then be used with the T-cold signal to calculate reactor coolant system loop Delta-T and T-average values for use in the reactor protection and plant control systems.
The averaging function will be accomplished by additions to existing 7300 reactor protection equipment.
The control system T-average and Delta-T signals are derived fra the reactor protection system T-average and Delta-T calculations and provided to the plant control system through isolation devices.
The isolation devices and control system input methodology for T-average and AT are not revised per this TS amendment and continue to meet the licensee basis as outlined in Chapter 7 of the Seabrook Station-Final Safety Analysis Report.
The licensee states that existing control board indicators and alarms provide a means to identify RTD failures. A cold leg RID failure can be handled by
' disconnecting the-failed element and connecting the spare element provided within each RCS loop.
A failure of a hot leg RTD c_n be managed in one of two ways.
The first method disconnects the failed hot leg RTD element and reconnects the spare element of the same RTD.
The second method requires plant personnel to manually defeat the failed hot leg RTD signal and rescale the electronics to average the remaining two RTD inputs. A bias value.is incorporated into the T-hot average signal to compensate for hot leg streaming and maintain a value comparable with the previous three RTD average.
The bias value is developed per procedure /TS requirements using data recorded at full power and during protection system surveillance, The proposed TS changes also include a revision to the precision heat balance requirements.
The licensee has modified the thermal power level at which the precision heat belance must be performed.
Previously, the heat balance was performed prior to exceeding 75% of rated power.
Now it will be performed prior to exceeding 95% of rated thermal power.
As stated by the licensee, i
this is consistent with the Westinghouse recommendation to perform the precision heat balance above 90% of rated thermal power to minimize measurement uncertainties aggravated at lower power levels.
1 The licensee stated that following the initial thermowell RTD cross calibration, the calibration reference will consist of_ the average of the RTD temperatures..The staff is concerned that the use of an average RTD value as a reference during cross calibration instead of a calibrated reference may lead to a net drift of the average temperature valve indicated by the RTDs over time should the installed RIDS drift systematically.
The licensee indicated that RTD drift is raniom'and with a total uncertainty of less than
.t 1.2 degrees specified in the submittal.
NUREG/CR-5560, " Aging of Nuclear flant Resistance Temnerature Detectors" recognizes that on-line crose calibration can be a reasonable method for RTD calibration.
However, as stated in NUREG/CR-5560, to perform in-situ calibration would normally require-
.one or more newly calibrated RTDs to be used as a reference.
Without a E
- r feret'ce the cross calibration will not account for common mode (systematic) drift and will only provide information on the consistency and not the accuracy of the installed RTDs.
The cross calibration technique assumes that the average of the RTD measurements represents the true process temperature and that RTD drift is random and not systematic.
The project results referenced in NUREG/CR-5560 indicate that RTD drift is usually random.
However, the particular testing done to validate the cross calibration methodology in NUREG/CR-5560 utilized newly calibrated RTDs for the test.
The staff agreed with the licensee's justification for RTD calibration without i
a reference but will continue to evaluate cross calibration techniques on a generic basis.
This is acceptable in that the bypass elimination RTDs are newly calibrated and should not be influenced by systematic drift components during the initial plant cross calibration at Seabrook.
2.1.3 Technical Specification Changes As a result of the modifications associated with the removal of the RTD bypa s manifold system, the licensee proposed various changes to the Seabrook Nuclear Station TS: The staff finds the following changes discussed in Section 2.1.3.1 through 2.1.3.4 acr.eptable.
2.1.3.1 Iable 2.2-1:
Rgtactor Trin System Instrumentation Setooints Ipp. 2-4. 2-5. 2-7.-2-8 and 2-10)
A.
Functional l' nit 7, Overtemperature AT.
Error terms I, S, and the associated note revised to reflect new RTD instrumentation uncertainties, temperature streaming and the Westinghouse setpoint methodology.- Note 2, Page 2-8, allowable value revised to 2.5% of AT span.
8.
Note 1, Page 2-7, the reference to manifold instrumentation is deleted to agree with new RTD measure,ent system.
C.
Functional Unit 8, Overpower AT.
Erive terms TA, Z, S-revised to reflect new RTO instrumentation uncertainties, temperature streaming and the Westinghouse setpoint methodology.
D.
Note 3, Page 2.10, the value for K6 has been increased.
The K6 constant in the keerpower AT equation provides compensation for Tavg greater than nomir' hyg by reducing the overpower AT setpoint. The increase in uncerick& :es associated with RTD bypass removal increased the Technica Specification TA value. As a result, the licensee increased the safety analysis limit for K4 to allow the TS value for nominal K4 to remain unaffected.
To account for this the margin in the Overpower AT setpoint equation for Tavg less than nominal Tavg was reduced and the value of K6 was increased to maintain the 118% thermal overpower limit.
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In addition, the Note 2 allowable value was changed to 2.0% of span as a result of the RTD bypass removal uncertainties.
E.
Functional Unit 12, Page 2-5, " Reactor Coolant flow Low," the terms for Z and allowable value are modified to incorporate the modified RTO instruaentation instrument uncertainties.
2.1.3.2 Table 4.3-1:
Reactor Trio Sys_1_em Instrumentation Surveillann Reauirements (pp. 3/4 3-9. 3/4 3-13)
Functional Unit 7, "0vartemperature AT," the requirement to check RTO bypass loop flow has been deleted to be consistent with the replacement of the RTO bypats manifold system.
2.1.3.3 Eases 3/4 2.5:
DNB Parameters (90. B 3/4 2-4).
The licensee (supplement 1) increased the measurement error for RCS total-flow rate from 2.1% to 2.4%.
The increase in flow measurement uncertainty reflects the values documented in WCAP-13181 for RTO bypass removal.
The 2.4% flow uncertainty also includes a 1% flow penalty.to account for possible feedwater venturl fouling.
2.1.3.4 Soecification 3/4.2.5:
DNB Parameters (op. 3/4 2-10)
Revised the surveillance requirements for the precision heat balance from prior to operation-above 75% of rated thermal power after each refueling to prior to exceeding 95% of rated thermal power.
Additionally, the DNB related parameter for reactor coolant system flow is increased from the current value of 391.000 gpm to a new value of 392,000 gpm by-supplement I to the licensee submittal. The
. revised value of RCS flow reflects increased uncertainties for RTD bypass removal and l'X flow penalty for possible feedwater venturi fouling.
2.2 Rustar Systems Inyn Sections 2.2;1 through 2.2.3 discuss the review of reactor systems issues.
2.2.1.Qurrent Method The current method of measuring the hot and cold leg rt.
tor coolant temperatures uses an RTD bypass system.
The hot a d cold leg temperature readings from each coolant loop are used for protection and control system inputs. The RTD bypass system was des gnad to address temperature streaming (non-uniform stratified flow in the cru section) in the hot legs and, by use of shutoff valves, to allow replacement of the direct immersion narrow-range RTDs without draindown of the. reactor coolant system (RCS).
For increased accuracy in measuring the hot leg temperatures, sampling coops were nlaced in each hot leg at three locations of a cross-section, 120' apart.
Eaca scoop l
has. five ' orifices' which sample that hot leg flow along the leading edge of the L
-scoop.
The-flow from the scoops is piped to a manifold where a direct L
l
k
' immersion RTD measures the average hot leg temperature of the flow stream from the three scocps in the hot leg.
This bypass flow is routed back at a point downstream of the steam generator.
The cold leg temperature is measured in a similar manner except that scoops are not used.
This is because temperature streaming is-not a problem due to the mixing action of the RCS pump.
2.2.2. New Method The new method proposed for measuring the hot and cold leg temperatures includes the use of narrow range dual element RTDs manufactured by WEED Company, which are mounted in tMrmowells to facil:cate replacement without draindown of the RCS. The average hot leg temperature and the cold leg temperature are used to generate the reactor coolant loop differential temperature (AT) and average temperature (T,,).
The hot leg temperature is: measured using three of the WEED RTDs.
Both elements of-each hot leg RTD are wired to the appropriate process instrument rack where the-second RTD input is a spare. The-thermowells are located-within two of the three existing RTD bypas manifold scoops, minimizing the
- need for additional hot leg piping penetrations.
The third RTD will be located in an independent penetration nozzle.
0n loops A, B, and D the independent penetration nozzle is located in the same cross-sectional plane as the existing scoops, but; offset 30' from the unused location. On. loop C, the penetration nozzle will be relocated to a position approximately 12 inches upstream of the existing scoops at approximately 105' from top dead center.
The unused scoops will be capped.
The Weed RTDs are mounte!, to line up with the center hole of the five holes in the scoop, in the cases where r.w penetration nozzles are made the WEED RTDs will be inserted to the same o nth as-those'in-the scoops, which-is the center hole depth.
Although unlikely, the RTD, or its electronics channel, _can fail-gradually,.
causing a gradual change-in the loop temperature measurements.- The licensee-has committed to take regular temperature measurements to monitor RTD f
' performance, so that any abnormal temperature shifts will be indicated.
An.RTD failure will most likely result in an off scale high or low indication and will, be detected through the existing control board T,,, and AT deviation alarms,' 'If-a_ failure of the RTD is diagnosed, two methods are available for -
addressing-the failed RTD.
Plant personnel can disconnect the failed element
'from the rack terminal. strip and connect the other RTD element. Another
-option-is for plant personnel to defeat the-failed hot leg RTD and rescale the electronics to average the remaining two_ signals and inconporate a bias based upon the~ hot streaming measured in the loop.
One RTD will be 1.ocated in each cold leg at the discharge of the reactor.
coolant pump.,Again.the existing RTD bypass penetration nozzle will be modified to accept ^ the' RT') thermowell. = 0ne ~ element of the RTD will be considered-active and the other. element will-'be reserved as a spare, if-a failure -of a coldLleg RTD is diagnosed, plant personnel can disconnect the
. failed element. from tne _ rack terminal' strip and connect the other RTD element.
f 2.2.3 Analysis The RTD response time is restricted with a technical specification Limiting Condition for Operation (LCO) to ensure consistency with assumptions in the accident enalyses. The licensee presented information regarding the response time of the new RTD measurement system and also the accuracy of the new method for measuring the hot leg temperature which is discussed below.
2.2.3.1 RTD Response Time The total response time for the current RTD bypass system and the proposed thermowell RTD system consist of the RTD bypass piping and thermal lag time, the RTD response time, and the elect onic delay.
The thermowell mounted RTDs have a response time equal to or better than the old bypass piping transport, thermal lag and direct immersion RTD.
This allows the total RCS temperature measurement response time specified in technical specifications to remain unchanged at 6.0 seconds.
NUREG-0809. indicated that RTD response times have been known to degrade and that the Loop Current Step Response (LCSR) methodology is the recommended on-site method for checking RTD response times.
The licensee has stated that they perform GTD response time testing, using the recommended LCSR method as stated in NUREG/CR-5560, for checking the RTD response time, which is acceptable to the staff.
Based on the above information the staff finds that the RTD response time has been addressed in an acceptable manner.
2.2.3.2 RTD Uncertainty The following protection and control system parameters were affected by the change _from one hot leg RTD to three hot leg RTDs; the Overtemperature delta T, Overpower delta T, Low RCS Flow rector trip functions, the RCS average temperature measurements used for control board indication and input to the rod control system, and the calculated value of the RCS flow uncertainty.
System calculations were performed for each of the parameters and the results indicated that a safficient margin exists to account for all known instrument uncertainties.
2.2.3.3 lign-LOCA Accidents Only those transients which assume overtemperature delta-T (OTAT) and overpower delta-T (0 PAT) protection function are potentially affected by changes in the RTD response time. As noted previously the new thermowell mounted RTDs have a response tir equal to or better than that of the old bypass transport, thermal lag a u1 Jirect immersion RTD.
Because the total channel response time remains less than or equal to 6.0 seconds, it is concluded that the safety analysis assumption for the total OTAT/0 PAT channel response +1me remains valid.
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, 4 The change in RTDs has caused the uncertainty on T,y to incren e from +/-4*F to +/-5'F.
However, +/-5'F is still less than +he uncertainty previously assumed in the non-LOCA r a ent analysis.
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The impact of the propowd increase in flow measuremret uncertainty (i.e.,
. A *d 0.3%) on non-LOCA accident has also been onsidered.
In this regard, the N'J w T Nsign Flow is used in the non-LOCA acciunt analysis and the uncertainty 's staff finds that the change in flow untrainty has no impact because Thermal MM 5 applied to the measured value of RCS flow.
.-4,
- 16. licensee determined that the RTD bypass elimination wes not increase any
' jy -
uncertainty that will affect any initial condition assumed in any non-LOCA M
transient or the low primary coolant flow reactor trip function.
Since the effect of the temperat'cre response time is unaf fe( ted and the accuracy of the new system is bounded, the conclusions in Chapter 15 of the Seabron FSAR remain valid.
{
'I 2.2.3
. _2n The the RTD bypass system impactr the uncertainties associated 1
with
.... per ai. ore and flow measurement.
However, the magnitude of the uncer.ainties are such that RCS inlet and outlet temperatures, thermal dtsign flow rate and the steam generator performance data used in the LOCA analyses will be affected only slightly.
(t+ 1 uncertaiaty for Seabrook Unit 1 is nos stated to increase to +/-5'F j
ret, a +/-4
- F.
Therefore sma'l peak cladding temperature (PCT) penalties have 7
been applied to both the large and Small Break LOCA anal.,ses of record to s
address the T uncertainty range increase.
The PCT increases are 4*F for largetreakLEAand8'FforsmallbreakLOCA(LetterfromT.C.Feigenbaum, North Atlantic Energy Service Corporation, to the NRC, "10 CFR 50.46 Annual t
'l Report," July 1, 1992). With these penalties the current PCT values become 2052.2*F for LBLOCA and 1981.2*F for SBLOCA.
The PCT remains well below the v
regulatory limit of 2200'F.
Thi: is acceptable to the staff.
2.2.3.5 Precision Heat Balance 2
The licensee has also proposed to change TS surve'llance requirement 4.2.5.3 a
to modify the performance of a precision heat bala. ice which is used to determine RCS flow rate and to normalize the RCS flew i..irumentation.
Currenti./ the TS requirements specify that the recision heat balance must be performed prior to operation above 75% of thermal rated power following each fuel loading. This calculation is performed each cycle to detect changes in the RCS flow element (elbow taps) tharacteristics thct would affect the accuracy of the RCS flow indication.
The 11 ensee: proposes that the precision heat balance be performed prior to exceecing 95% thermal rated power to minimize the measurement uncertainties that are exacerbated at lovier power levels.
Performing the flow rate measuremer,t prior to exceeding 95% rated tb?rmal power provides a reasonable amount of excess margin to DNB in the higP improbable event that a
F u
, : degradation _in RCS flow rate, maked by a simultaneous non-conservative change in all elbow taps, is not detected prior to reaching 95%.
On this basis, the staff _ accepts the licensee's proposed change.
2.2.3.6 DNB Parameters.
The-licensee also proposed a change to.
. 2.5 regarding DNB parameters.
Currently the RCS flow rate is specified at greater than or equal to 391,000 gpm, which includes 2.1% flow uncertainty.
The proposed change to 392,000 includes the thermal design flow of 382,800 gpm plus the cold leg elbow tap flow uncertainty o_f 2.'4% flow.
The 2.4% flow uncertainty include 0.1%
penalty for undetected feedwater venturi fouling.
The staff firus the change in the flow rate acceptable.
3.0 STATE CONSULTATION
In accordance with the Commission's ragulations, ths New Hampshire and
' Massachusetts State officials were notified of the proposed issuance of the amendment.
The State officials had no comments.
4.0 ENVIRONMENTAL CONSIDERATIM The amendment changes a requirement with respect to installation or use of a facility component located within the restricted area as defined in 10 CFR
'Part 20 and changes surveillance rcquirements.
The NRC staff has determined that the tmendment involves no significant increase in the amounts, and no significant change in the types, of any effluents tnat may be released offsite, and_ that there is no-significant increase in individu&l or cumulative occupational radiation exposure. The Commission has previously issued a
' proposed -finding that the amendment involves no significant hazards consideration, and there has been no public comment on sua finding (57 FR 30256). Accordingly, the amendment meets the eligibM Py criteria for categorical exclusion set forth in 10 CFR 51.22(c)(9).
9:'rsuant to 10 CFR 51.22(b) no environmental impact statement or environmer.a1 assessment need be
-prepared in connection with the issuance of the amendment.
3.0 CONCLUSION
To support the modifications required to iliminate the RTD bypass manifold system, the licensee proposud changes to the Seabrook Station TS.
The TS revisions are a result of differences in the instrument system uncertainties between the thermowell-mounted RTD system and the bypass manifold temperature meastcement system.
Evaluations performed by the licensee indicate that the instrument uncertainty values are acceptable.
The impact of eliminating the RTD bypass systen.for Seabrook~ Station on FSAR Chapter 15 accidents has also been evaluated by the licensee.
The review by the staff supports these conclusions. -Since ine RTD temperature respcase time and accuracy of the new system.is not' degraded, the former conclusions in the FSAR remain valid, and acceptablecas described in Section 2.0.
4 The staff :oncludes that the modified RTD system is not functionally different from the current system except for the use of three RTDs instead of one in each hot leg.
Based on the above, the staff finds that the proposed plant modifications to replace the RTD bypass manifold system with thermowell mounted, fast response, narrow range RTDs located direct in the reactor coolant system piping and the proposed TS changes are acceptable.
The Commission has conj 1uded, based o' 'he considerations discussed above.
- that:
(1) there is reasonble assurai, that the healti, and safety of the public will not be endangered by operatwo in the proposed manner, (2) such activities will be conducted in compliance with the Commission's reguin ions, and (3) the issuance of the amendment will not be inimical to the common defense and security or to the health and safety of the public.
Principal Contributors:
C. Doutt S. Brewer Date: August 10, 1992 M
h i
I AMENDMENT N0.12 TO NPF-86 SEABROOK STATION DATED August 10, 1992 s.
DISTRIBVUON:
y Dockct File 50-443 NRC PDR & Local PDR PDI-3 Reading S. Varga J. Calvo M. Rushbrook V. Nerses G. Edison K. Battige OGC - 15 B18 Dennis Hagan - MNBB 320'-
E. Jordan - MNBB 3701 B. Grimes - 9 A3 G. Hill (4) Pl-37 Vanda Jones - 7103 HNBB C. Grimes - 11 F23 ACRS (10) P - 315 PA - 2 G5 0C/LFMB - MNBB J. Linville, Region I R. Lobel S. Brewer, 8 E23 C. Doutt, 8 H3
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