NRC-98-0071, Application for Amend to License NPF-43,proposing Align Shutdown Action Statements for Primary Containment Oxygen Monitoring Instrumentation in Three Specifications

From kanterella
(Redirected from NRC-98-0071)
Jump to navigation Jump to search
Application for Amend to License NPF-43,proposing Align Shutdown Action Statements for Primary Containment Oxygen Monitoring Instrumentation in Three Specifications
ML20216J747
Person / Time
Site: Fermi DTE Energy icon.png
Issue date: 04/09/1998
From: Gipson D
DETROIT EDISON CO.
To:
NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
Shared Package
ML20216J752 List:
References
CON-NRC-98-0071, CON-NRC-98-71 NUDOCS 9804210476
Download: ML20216J747 (13)
v • d • e


Text

.

Douglas R. Gipson Senior Vice Presi< tent, Nuclear Generation Fermi 2 6490 North Dixie llwy, Newport, Michigan 48166 Tel: 3115MI>20l Fax: 3116M.4172 Detroit Edison 10CFR50.92 April 9,1998 NRC-98-0071 1

U. S. Nuclear Regulatory Commission Attention: Document Control Desk Washington D C 20555-0001

References:

1) Fermi 2 NRC Docket No. 50-341 NRC License No. NPF-43

)

2) NUREG 1433, Revision 1," Standard Technical Specifications i

General Electric Plants, BWR/4"

Subject:

Proposed Technical Specification Change (License Amendment) to Align the Shutdown Action Statements, and the Entry Conditions for the Shutdown Action Statements, for the Primary Containment Oxygen Monitoring Instrumentation in Technical Specifications 3.3.7.5. 3.7.1.2. and 3.8.1.1.

Pursuant to 10CFR50.90, Detroit Edison hereby proposes to amend the Fermi 2 Plant Operating License NPF-43, Appendix A, Technical Specifications. Technical Specification 3.7.1.2, Action a and Technical Specification 3.8.1.1, Action c are more restrictive when applied to primary containment oxygen monitoring instrumentation than is the specific Technical Specification for the primary containment oxygen monitoring instrumentation, Specification 3.3.7.5. Detroit Edison proposes to align the shutdown action statements, and the entry conditions for the shutdown action statements, for the primary containment oxygen monitoring instrumentation in all three Specifications. This change is consistent with the Improved Technical Specifications (Reference 2).

Technical Specification Limiting Condition for Operation 3.7.1.2, Action a currently requires that "Within 2 hour2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br />s: a) venfy that all required systems, subsystems, trains, d components and devices that depend upon the remaining OPERABLE [ Emergency

.n

.x u-9804210476 980409

[

PDR ADOCK 05000341 p

PDR A DTE Enero Company

USNRC NRC-98-0071 Page 2 Equipment Cooling Water] EECW system subsystem are also OPERABLE...

Othenvise**, be in at least HOT SHUTDOWN within the next 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> and in I

COLD SHUTDOWN within the following 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />." The footnote ** provides an exception for an inoperable drywell cooling unit (Technical Specification 3.7.11) in the opposite division. It allows the Action for Specification 3.7.11 to be taken for the l

inoperability of both required drywell cooling units rather than requiring an immediate entry into the 12 hour1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> shutdown statement of Specification 3.7.1.2,

)

Action a. Detroit Edison is proposing similar relief for the primary containment oxygen monitoring instrumentation in the opposite division. Detroit Edison proposes that for the primary containment oxygen monitoring instmmentation, the Actions contained in Technical Specification 3.3.7.5 for both divisions of primary contaimnent oxygen monitoring instrumentation inoperable be taken rather than -

requiring immediate entry into the 12 hour1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> shutdown statement of Technical Specification 3.7.1.2, Action a.

Likewise, Technical Specification 3.8.1.1, Action c states "With one or both diesel generators in one of the above required onsite A.C. electrical power divisions inoperable, in addition to ACTION b, above, verify within 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> that all required systeins, subsystems, trains, components and devices that depend on the remaining onsite A.C. electrical power division as a source of emergency power are also OPERABLE; otherwise, be in at least HOT SHUTDOWN within the next 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> and in COLD SHUTDOWN within the following 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />." Detroit Edison l

proposes that for inoperable primary containment oxygen monitoring instrumentation, the Actions contained in Technical Specification 3.3.7.5 for both divisions of primary containment oxygen monitoring instrumentation inoperable be taken rather than requiring immediate entry into the 12 hour1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> shutdown statement of Technical Specification 3.8.1.1, Action c.

]

Both Technical Specification 3.7.1.2, Action a and Tecimical Specification 3.8.1.1, Action c are more restrictive in requiring immediate entry into a 12 hour1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> shutdown action statement for the primary containment oxygen monitor in the opposite division being inoperable, than is the specific Technical Specification for both channels of primary containment oxygen monitoring instrumentation being inoperable. Technical Specification 3.3.7.5, states "With the number of OPERABLE accident monitoring instrumentation channels less than the Minimum Channels OPERABLE requirements of Table 3.3.7.5-1, restore the inoperable channel (s) to OPERABLE status within 48 hours5.555556e-4 days <br />0.0133 hours <br />7.936508e-5 weeks <br />1.8264e-5 months <br /> or be in at least HOT SHUTDOWN within the next 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br />. They are also more restrictive in that both Technical Specification 3.7.1.2, Action a and Technical Specification 3.8.1.1, Action c require the plant to be brought to COLD SHUTDOWN, whereas Technical Specification 3 3.7.5, Table 3.3.7.5.1 Action 83 requires only that the plant be brought to HOT SHUTDOWN.

Detroit Edison proposes to align the shutdown action statements, and the entry j

conditions for the shutdown action statements, for the primary containment oxygen

L USNRC NRC-98-0071 Page 3 i

monitoring instrumentation in all three Specifications. This change is consistent with the Improved Technical Specifications (Reference 2). provides a description and an evaluation of the proposed Technical

' Specification changes. Enclosure 2 provides an analysis of the issue of significant hazards consideration using the standards in 10CFR50.92. Enclosure 3 provides the hand marked pages of the existing Technical Specifications to show the proposed j

changes and a typed version of the affected Technical Specification pages with the l

proposed changes incorporated.

i l

Detroit Edison has reviewed the proposed Technical Specification changes against the criteria in 10CFR51.22 for environmental considerations. The proposed changes do not involve a significant hazards consideration, nor do they significantly change the types or significantly increase the amounts of effluents that may be released l

offsite. The proposed changes also do not significantly increase individual or j-cumulative occupational radiation exposures. Based on the foregoing, Detroit Edison concludes that the proposed Technical Specification changes meet the criteria provided in 10CFR51.22(c)(9) for a categorical exclusion from the requirements for j

an EnvironmentalImpact Statement or an Environmental Assessment.

Detroit Edison requests that this license amendment request be approved as soon as l

possible to provide full utilization of the changes granted in License Amendment 117 with an implementation period of within 30 days following NRC approval. There are no commitments being made in this letter.

Should you have any questions or require additional information, please contact Mr. Norman K. Peterson of my staff at (734) 586-4258.

Sincerely,

)

Enclosures cc: A. B. Beach B. L. Burgess G. A. Harris A. J. Kugler Supervisor, Electric Operators, Michigan Public Service Commission i

/

p 4

USN'RC NRC-98-0071 Page 4 J

I, DOUGLAS R. GIPSON, do hereby affirm that the foregoing statements are based 2

on facts and circumstances which are true and accurate to the best of my knowledge and belief.

1

)

I 4

NY DOUGLAS RdGIPSON Senior Vice President, Nuclear Generation IS 1998 before me personally On this day of ~

appeared Doug'las R. Gipson, being first duly sworn and says that he executed the foregoing as his free act and deed.

LuYw fXLh l

No'tary Public ROSAUE A. AAMETTA NOTARY PU3LIO-MONROE COUm *!*

MYCOMMISSION BGES1W1150 4

A

Enclosure I to NRC-98-0071 i

Page1

)

I l

ENCLOSURE 1 FERMI 2 NRC DOCKET NO. 50-341 OPERATING LICENSE NO. NPF-43 REQUEST TO REVISE TECHNICAL SPECIFICATIONS:

Proposed Technical Specification Change (License Amendment) to Align the Shutdown Action Statements, and the Entry Conditions for the Shutdown Action Statements, for the Primary Containment Oxygen Monitoring Instrumentation in Technical Specifications 3.3.7.5,3.7.1.2, and 3.8.

1.1 DESCRIPTION

AND EVALUATION OF THE PROPOSED CIIANGES

  • ., to NRC-98-0071 Page 2 DESCRIPTION AND EVALUATION OF THE PROPOSED CHANGE (S)

DESCRIPTION Technical Specification Limiting Condition for Operation 3.7.1.2, Action a currently requires that "Within 2 hour2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br />s: a) verify that all required systems, subsystems, trains, components and devices that depend upon the remaining OPERABLE EECW system subsystem are also OPERABLE... Otherwise**, be in at least HOT SHUTDOWN within the next 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> and in COLD SHUTDOWN within the following 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />."

The footnote ** provides an exception for an inoperable drywell cooling unit (Technical Specification 3.7.11)in the opposite division. It allows the Action for Specification 3.7.11 to be taken for the inoperability of both required drywell cooling units rather than requiring an immediate entry into the 12 hour1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> shutdown statement of Specification 3.7.1.2, Action a. Detroit Edison is proposing similar relief for an inoperable primary containment oxygen monitoring instrument in the opposite division. Detroit Edison proposes that for the primary containment oxygen monitoring instrumentation, the Actions contained in Technical Specification 3.3.7.5 for both divisions of primary containment oxygen monitoring instrumentation inoperable be taken rather than requiring immediate entry into the 12 hour1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> shutdown statement of Technical Specification 3.7.1.2, Action a.

Likewise, Technical Specification 3.8.1.1, Action c states "With one or both diesel generators in one of the above required onsite A.C. electrical power divisions inoperable, in addition to ACTION b, above, verify within 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> that all required systems, subsystems, trains, components and devices that depend on the remaining onsite A.C. electrical power division as a source of emergency power are also OPERABLE; otherwise, be in at least HOT SHUTDOWN within the next 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> and in COLD SHUTDOWN within the following 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />." Detroit Edison proposes that for an inoperable primary containment oxygen monitoring instrumentation channel in the opposite division, the Actions contained in Technical Specification 3.3.7.5 for both divisions of primary containment oxygen monitoring instrumentation inoperable be taken rather than requiring immediate entry into the 12 hour1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> shutdown statement of Technical Specification 3.8.1.1, Action c.

- Both Technical Specification 3.7.1.2, Action a and Technical Specification 3.8.1.1, Action c are more restrictive in requiring immediate entry into a 12 hour1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> shutdown action statement when applied to a primary containment oxygen monitoring instrumentation channel that is considered inoperable when either the EECW subsystem or one or both emergency diesel generators (EDGs) in that division are inoperable, and the primary containment oxygen monitoring instrumentation channel in the opposite division is also inoperable, than is the specific Technical

7 I

i to j

l NRC-98-0071 Page 3 Specification for the primary containment oxygen monitoring instrumentation, Specification 3.3.7.5, which states "With the number of OPERABLE accident monitoring instrumentation channels less than the Minimum Channels OPERABLE

)

requirements of Table 3.3.7.5-1, restore the inoperable channel (s) to OPERABLE status within 48 hours5.555556e-4 days <br />0.0133 hours <br />7.936508e-5 weeks <br />1.8264e-5 months <br /> or be in at least HOT SHUTDOWN within the next 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br />.

They are also more restrictive in that both Technical Specification 3.7.1.2, Action a l

and Technical Specification 3.8.1.1, Action c require the plant to be brought to COLD SHUTDOWN, whereas Technical Specification 3.3.7.5, Table 3.3.7.5.1 Action 83 requires only that the plant be brought to HOT SHUTDOWN.

A change to the Technical Specification 3.7.1.2 Action a and Technical Specification 3.8.1.1 Action c requirements is being requested because both of these Action statements are more restrictive regarding the time allowed for both primary containment oxygen monitoring instrumentation channels to remain inoperable prior to requiring a plant shutdown than is Technical Specification 3.3.7.5, pertaining specifically to the primary containment oxygen monitoring instrumentation, which requires that the plant be brought to HOT SHUTDOWN only if one channel cannot i

be restored to OPERABLE status within 48 hours5.555556e-4 days <br />0.0133 hours <br />7.936508e-5 weeks <br />1.8264e-5 months <br />. The shutdown action statement entry conditions for the primary containment oxygen monitoring instrumentation should be no more restrictive in Technical Specification 3.7.1.2 or Technical Specification 3.8.1.1, than it is in Technical Specification 3.3.7.5. The primary containment oxygen monitoring instrumentation provides the same non-critical i

function regardless of the reason for the system inoperability. Additionally, recent f

guidance from Reference 2 no longer requires immediate entry into a shutdown j

action statement when equipment in the opposite division is inoperable and either one EECW system or one or both EDGs in one division become inoperable. Rather, j

Reference 2, Electrical Power Systems, Specification 3.8.1 Required Action A.2 l

requires that required equipment be declared inoperable when its associated j

emergency diesel generator becomes inoperable and the corresponding equipment in the cpposite division is also inoperable, and Plant Systems, Specification 3.7.2 i

Action C allows one EECW subsystem to be inoperable for up to 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br />. The evaluation performed in accordance with the safety function determination program required by LCO 3.0.6 in Reference 2 for an inoperable primary containment oxygen monitoring instrumentation channel in the opposite division would lead to a Required Action of restoring one channel to OPERABLE status within 48 hours5.555556e-4 days <br />0.0133 hours <br />7.936508e-5 weeks <br />1.8264e-5 months <br />.

Reference 2 thus provides relief similar to that being requested in this proposed license amendment change.

Technical Specification 3.3.7.5 currently allows one channel of primary containment oxygen monitoring instrumentation to remain inoperable for up to 30 days, and beyond, without requiring a plant shutdown. However, with one channel of primary containment oxygen monitoring instrumentation inoperable, required surveillance testing of an EDG or an EECW subsystem in the opposite division would place the

1 Page 4 i

l j

j plant in the immediate shutdown action statements of Technical Specification 3.7.1.2

)

or Technical Specification 3.8.1.1 as described above, without any margin of time for preventive or corrective maintenance. This change will allow continued operation in l

Operational Conditions 1 and 2 with both primary containment oxygen monitoring l

instrumentation channels inoperable for any reason for up to 48 hours5.555556e-4 days <br />0.0133 hours <br />7.936508e-5 weeks <br />1.8264e-5 months <br />. This change 4

l will still require the plant to be shut down within 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br />, if one channel of the l

primary containment oxygen monitoring instrumentation cannot be restored to OPERABLE status within 48 hours5.555556e-4 days <br />0.0133 hours <br />7.936508e-5 weeks <br />1.8264e-5 months <br /> after determining that both channels are l

inoperable.

l EVALUATION l

The purpose for the immediate entry into a shutdown action statement in Technical Specification 3.7.1.2 Action a, as stated in the Technical Specification Bases for this

' Specification, is to provide assurance that a complete loss of safety function of critical systems does not exist during the period that one of the EECW subsystems is inopemble. Similarly, the purpose for the immediate entry into a shutdown action statement in Technical Specification 3.8.1.1 Action c, as stated in the Technical i

i Specification Bases for this Specification, is to provide assurance that a loss of offsite power event will not result in a complete loss of safety function of critical

]

systems during the period that one or both of the diesel generators in one division is i

inoperable.

Fermi 2 has an inerted primary containment atmosphere during reactor operation.

Because of this, in the event of a LOCA, the oxygen concentration is the limiting parameter for preventing the accumulation of an explosive gas mixture. The hydrogen and oxygen concentrations are monitored during operation and following a LOCA by the primary containment hydrogen and oxygen monitors, and are displayed in the control room. The primary containment hydrogen and oxygen monitors are part of the Primary Containment Monitoring System (PCMS). The primary containment hydrogen and oxygen monitoring systems consist of two divisions, each division containing one channel or subsystem for each function. The primary containment hydrogen and oxygen monitoring systems continuously sample the containment atmosphere during Operational Conditions 1 and 2 when required to be operable by the Technical Specifications. One division for each function is normally aligned to the drywell, with the other division aligned to the suppression chamber. The primary containment hydrogen and oxygen monitors provide information to the control room operators for monitoring hydrogen and oxygen concentrations in the primary containment so that actions can be initiated, if necessary, to prevent the accumulation of an explosive gas mixture.

, to NRC-98-0071 Page 5 i

l The primary containment hydrogen and oxygen monitors are classified as Regulatory Guide 1.97, " Instrumentation for Light Water Cooled Nuclear Power Plants to Assess Plant and Environs Conditions During and Following an Accident," Category I, Type C instruments. Type C instruments provide information to indicate the potential for breaching or the actual breach of the barriers to fission product release.

The primary containment hydrogen and oxygen monitors are used to detect high l

hydrogen and oxygen concentrations in primary containment which could lead to a containment breach. The primary containment hydrogen and oxygen monitors are also used for verifying the adequacy of mitigating actions following an accident.

They provide an alarm in the main control room on high hydrogen or high oxygen concentration, but provide no automatic function to prevent or mitigate any of the Updated Final Safety Analysis Report (UFSAR) analyzed accidents.

Because these instruments provide no automatic function in preventing or mitigating any of the Updated Final Safety Analysis Report (UFSAR) analyzed accidents, no analysis of accident mitigation functions for these instmments is needed. Technical Specification 3.6.6.2 continues to require the drywell and suppression chamber atmosphere oxygen concentration to remain less than 4% by volume during Operational Conditions 1 and 2. The loss of both channels of primary containment oxygen monitoring instrumentation is not critical for entry into the Emergency Operating Procedures. Entry conditions for the post accident control of hydrogen are based upon the primary containment hydrogen monitors, and both channels of j

primary containment hydrogen monitoring instrumentation are still required to j

remain operable in accordance with Technical Specification 3.3.7.5. Additionally, j

alternate methods using grab samples and laboratory analytical equipment are I

available for obtaining hydrogen and oxygen concentratior.s if the respective instruments are not available.

l

. Based upon the discussion above, the primary containment oxygen monitoring instrumentation is not considered to be part of a " critical system" as used in the

{

Bases of the Technical Specifications. These instruments provide indication and an I

alarm in the main control room on high oxygen concentration, but provide no automatic function to prevent or mitigate any of the Updated Final Safety Analysis Report (UFSAR) analyzed accidents. With both channels of the primary containment oxygen monitoring instrumentation inoperable, the operators still have the ability to diagnose an accident using altemative insttuments ard methods (grab i

samples and laboratory analytical equipment). Additionally, the probability of an l

event requiring this post accident monitoring instrumentation during the 48 hour5.555556e-4 days <br />0.0133 hours <br />7.936508e-5 weeks <br />1.8264e-5 months <br /> interval allowed by Technical Specification 3.3.7.5 for both channels of primary 1

containment oxygen monitoring instrumentation to be inoperable is low.

i

4

. to NRC-98-0071 Page 6 l

The current Technical Specification 3.7.1.2 Action a and Technical Specification 3.8.1.1 Action c requirements to continue to COLD SHUTDOWN upon loss of both divisions of primary containment oxygen monitoring instrumentation is unnecessary l

l because these instruments are only required by Technical Specification 3.3.7.5 to be OPERABLE in Operational Conditions 1 and 2. Shutdown to HOT SHUTDOWN (Operational Condition 3) is sufficient to exit the Technical Specification 3.3.7.5 l

l Applicability for this instrumentation. The limitation of the Applicability for this

'j j

instrumentation in Technical Specification 3.3.7.5 to Operational Conditions 1 and 2

{

only, is further indication that this instrumentation is not considered part of a " critical l

system" as used in the Bases of Technical Specifications 3.7.1.2 and 3.8.1.1. Critical j

l systems (i.e., those needed to prevent or mitigate accidents and to ensure the plant

{

can be brought to COLD SHUTDOWN), are typically required in Operational Conditions 1,2, and 3.

1 l

l l

~'

' to NRC-98-0071 Page1 l

ENCLOSURE 2 FERMI 2 NRC DOCKET NO. 50-341 NRC LICENSE NO. NPF-43 REQUEST TO REVISE TECIINICAL SPECIFICATIONS:

Proposed Technical Specification Change (License Amendment) to Align the Shutdown Action Statements, and the Entry Conditions for the Shutdown Action Statements, for the Primary Containment j

Oxygen Monitoring Instrumentation in Technical Specifications 3.3.7.5,3.7.1.2, and 3.8.1.1 10CFR50.92 SIGNIFICANT II AZARDS CONSIDERATION

)

i

{

I j

,- to NRC-98-0071 Page 2 10CFR50.92 SIGNIFICANT HAZARDS CONSIDERATION l

In accordance with 10CFR50.92, Detroit Edison has made a determination that the proposed amendment involves no significant hazards consideration. The proposed Technical Specification changes described above do not involve a significant hazards consideration for the following reasons:

1. The change does not involve a significant increase in the probability or consequences of an accident previously evaluated.

The proposed change will permit operation with both of the primary containment crygen monitoring instrument channels inoperable for up to 48 hours5.555556e-4 days <br />0.0133 hours <br />7.936508e-5 weeks <br />1.8264e-5 months <br /> before requiring entry into a 12 hour1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> shutdown statement, consistent with Technical Specification 3.3.7.5, but less restrictive than the requirements in Technical Specification 3.7.1.2 Action a and Technical Specification 3.8.1.1 Action c, which require entry into the 12 hour1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> shutdown statement immediately if the l

channel in the remaining division is inoperable, followed by continued shutdown to the COLD SHUTDOWN condition. The shutdown action statement entry conditions for the primary containment oxygen monitoring instrumentation l

should be no more restrictive in Technical Specification 3.7.1.2 or Technical Specification 3.8.1.1, than they are in Technical Specification 3.3.7.5 for both channels being inoperable. The primary containment oxygen monitoring instrumentation provides the same non-critical function regardless of the reason for the system inoperability. The primary containment oxygen monitors provide the control room operators with indication and alarm of the oxygen concentration in the primary containment, but do not provide any automatic function to mitigate an accident. Because they perform only a monitoring function, the oxygen monitors are not associated with the initiation of any previously evaluated accident; therefore, there is no change in the probability of an accident previously evaluated.

The indication provided by the primary containment oxygen monitors is used by L

the control room operators to ensure that the oxygen concentration remains l

within limits and to help make decisions regarding the use of the Combustible Gas Control System, if necessary. Altemate methods using grab samples and laboratory analytical equipment are available for obtaining primary containment oxygen concentration if no primary containment oxygen monitoring i

instrumentation is available. Additionally, the loss of both oxygen analyzers is not critical for entry into the Emergency Operating Procedures. Entry conditions

(

for the post accident control of hydrogen are based upon the primary containment hydrogen monitor readings, and both channels of primary comainment hydrogen

- to l

NRC-98-0071 Page 3 l

L monitoring instrumentation are still required to remain operable in accordance with Technical Specification 3.3.7.5. Therefore, this change will not involve a significant increase in the consequences of a previously evaluated accident.

2. The change does not create the possibility of a new or different kind of accident from any accident previously evaluated.

As discussed above, the primary containment oxygen monitors are indication and l

alarm only instruments which provide information to the control room operators.

l The proposed change does not introduce a new mode of plant operation, nor does it involve a physical modification to the plant. Therefore, the proposed change does not create the possibility of a new or different kind of accident from any previously evaluated.

l

3. The change does not involve a significant reduction in the margin of safety.

The proposed change involves the length of time that both primary contaimnent oxygen monitoring instrument channels may be out of service. It does not increase the out of service time beyond what is already allowed by Technical Specification 3.3.7.5 for both channels being inoperable. The primary contai.7 ment oxygen monitors are indication and alarm only instruments which do not affect any parameters or assumptions used in the calculation of any safety margin associated with Technical Specification Safety Limits, Limiting Safety System Settings, Limiting Control Settings or Limiting Conditions for Operation, or other previously defined margins for any structure, system, or component. Therefore, the proposed changes do not involve a significant reduction in a margin of safety.

I l

J

Retrieved from "https://kanterella.com/w/index.php?title=NRC-98-0071,_Application_for_Amend_to_License_NPF-43,proposing_Align_Shutdown_Action_Statements_for_Primary_Containment_Oxygen_Monitoring_Instrumentation_in_Three_Specifications&oldid=3967664"