ML042430467

Units 1 and 2 - Technical Specification (TS) Change No. 02-01, Revision 1 - Nominal Trip Setpoints for Reactor Protection System (RPS) and Engineered Safety Features (ESF) Instrumentation

ML042430467
Person / Time
Site:	Sequoyah
Issue date:	08/18/2004
From:	Salas P Tennessee Valley Authority
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
TVA-SQN-TS-02-01, Rev 1
Download: ML042430467 (73)

Text

{{#Wiki_filter:Tennessee Valley Authority, Post Office Box 2000, Soddy-Daisy, Tennessee 37384-2000 August 18, 2004 TVA-SQN-TS-02-01, Revision 1 U.S. Nuclear Regulatory Commission ATTN: Document Control Desk Washington, D. C. 20555 Gentlemen: 10 CFR 50.90 In the Matter of Tennessee Valley Authority ) Docket Nos. 50-327 50-328 SEQUOYAH NUCLEAR PLANT (SQN) UNITS 1 AND 2 - TECHNICAL SPECIFICATION (TS) CHANGE NO. 02-01, REVISION 1 - NOMINAL TRIP SETPOINTS FOR REACTOR PROTECTION SYSTEM (RPS) AND ENGINEERED SAFETY FEATURES (ESF) INSTRUMENTATION

Reference:

TVA letter to NRC dated November 15, 2002, "Sequoyah Nuclear Plant (SQN) - Units 1 and 2 - Technical Specification (TS) Change No. 02 Nominal Trip Setpoints for Reactor Protection System (RPS) and Engineered Safety Features (ESF) Instrumentation and Relocation of Loss of Power and Radiation Monitoring Instrumentation Requirements" In accordance with the provisions of 10 CFR 50.90, TVA is submitting a request for an amendment to SQN's licenses DPR-77 and 79 to change the TSs for Units 1 and 2. The proposed change is a revision to the referenced request that supercedes the original request in its entirety. The proposed change will revise the trip setpoint column of the RPS and ESF instrumentation tables to utilize a nominal setpoint value and revise the associated Bases discussions.

U.S. Nuclear Regulatory Commission Page 2 August 18, 2004 The column will be relabeled "Nominal Trip Setpoint" with the inequalities removed from applicable values. The term "trip setpoint" has been evaluated throughout the TSs and has been revised to "nominal trip setpoint" as necessary and the use of the term "nominal" has been eliminated as appropriate. This change is being requested in response to NRC concerns regarding the use of inequalities for RPS and ESF nominal trip setpoint values. This concern was identified in NRC Inspection Report Nos. 50-327 and 50-328/95-26. This change is also consistent with NRC proposed and approved Technical Specification Task Force (TSTF) Item TSTF-355. This revised request does not implement the TSTF-355 recommendation for one ESF radiation monitoring instrumentation function. Revisions are being made to the RPS underfrequency reactor coolant pump (RCP) nominal trip setpoint and allowable value, the RPS undervoltage RCP allowable value, and the fuel storage pool area radiation monitor trip setpoint to correct a non-conformance. The intermediate range neutron flux P-6 nominal trip setpoint and allowable value is being revised to improve the adequacy of this setpoint with respect to the nominal setpoint application. Also included is a reduction in the number of timers required for loss of power instrumentation functions. TVA has determined that there are no significant hazards considerations associated with the proposed change and that the change is exempt from environmental review pursuant to the provisions of 10 CFR 51.22(c)(9). The SQN Plant Operations Review Committee and the SQN Nuclear Safety Review Board have reviewed this proposed change and determined that operation of SQN Units 1 and 2 in accordance with the proposed change will not endanger the health and safety of the public. Additionally, in accordance with 10 CFR 50.91(b)(1), TVA is sending a copy of this letter and attachments to the Tennessee State Department of Public Health. to this letter provides the description and evaluation of the proposed change. This includes TVA's determination that the proposed change does not involve a significant hazards consideration, and is exempt from

U.S. Nuclear Regulatory Commission Page 3 August 18, 2004 environmental review. contains copies of the appropriate TS pages from Units 1 and 2 marked-up to show the proposed change. There are no new regulatory commitments being made by this submittal. TVA does not have any specific schedule requirements for this request and processing can be pursued as necessary. TVA requests that the revised TS be made effective within 45 days of NRC approval. If you have any questions about this change, please telephone me at (423) 843-7170 or J. D. Smith at (423) 843-6672. Sincerely, Pedro Salas Licensing and Industry Affairs Manager I declare under penalty of perjury that the foregoing is true and correct. Executedon this 18th day of August, 2004. Enclosures cc (Enclosures): Framatome ANP, Inc. P. 0. Box 10935 Lynchburg, Virginia 24506-0935 ATTN: Mr. Frank Masseth Mr. Robert J. Pascarelli, Senior Project Manager U.S. Nuclear Regulatory Commission Mail Stop O-7A15 One White Flint North 11555 Rockville Pike Rockville, Maryland 20852-2739 Mr. Lawrence E. Nanney, Director Division of Radiological Health Third Floor L&C Annex 401 Church Street Nashville, Tennessee 37243-1532

ENCLOSURE 1 TENNESSEE VALLEY AUTHORITY SEQUOYAH NUCLEAR PLANT (SQN) UNITS 1 and 2 DOCKET NOS. 327 AND 328 PROPOSED TECHNICAL SPECIFICATION (TS) CHANGE 02-01, REVISION 1 DESCRIPTION AND EVALUATION OF THE PROPOSED CHANGE I. DESCRIPTION OF THE PROPOSED CHANGE The proposed TS change will rename the Trip Setpoint column of TS Tables 2.2-1 and 3.3-4, remove the inequality signs for the trip setpoint values as appropriate, and revise the inequality representation for the allowable values (Avs) as needed. The new title for the Trip Setpoint column will be Nominal Trip Setpoint. Bases discussions clarify operable conditions for the functions and prescribe conditions where the setpoints may be set more conservatively. There is one exception to this nominal trip setpoint implementation. This is the trip setpoint for TS Table 3.3-4, Item 3.c.3, "Containment Purge Air Exhaust Monitor Radioactivity-High," where the inequality will be retained. This revision also includes the revision of other locations in the TSs that currently use the term "trip setpoint" and need to be changed to "nominal trip setpoint" to be consistent with the table title. The term "nominal" will be removed from the average temperature at rated thermal power (T') definition in Table 2.2-1, Note 1. The current trip setpoints will now be represented by a nominal value that will not include an inequality sign. This change does not alter the value of the trip setpoint except as noted below. Avs that are currently represented with a numerical value and a tolerance expressed as a plus or minus, are revised to utilize a representation with inequalities that retains the current limits. Additional changes are proposed to the TS instrumentation tables that involve the revision of three trip setpoints, three Avs, and required minimum channels operable. Specifically, the nominal trip setpoint for the reactor coolant pump (RCP) underfrequency reactor trip in TS Table 2.2-1 has been changed from 56.0 Hertz (Hz) to 57.0 Hz. The Avs for the RCP underfrequency and undervoltage function in TS Table 2.2-1 have been revised. The E1-1

underfrequency value has been changed from greater than or equal to 55.9 Hz to greater than or equal to 56.3 Hz. The undervoltage Av has been changed from greater than or equal to 4739 volts to greater than or equal to 4952 volts. The intermediate range neutron flux P-6 nominal trip setpoint in TS Table 2.2-1 will be revised from 1 x l0-5 percent of rated thermal power (RTP) to 1 x 10-4 percent RTP. The P-6 allowable value changes from 6 x 10-6 percent RTP to 6 x 10-5 percent RTP. The fuel storage pool area monitor alarm/trip setpoint in TS Table 3.3-6 has been changed from less than or equal to 200 milli roentgen equivalent man (mR) per hour (hr) to less than or equal to 151 mR/hr. The required minimum channels operable for the auxiliary feedwater (AFW) and emergency diesel generator (EDG) loss of power start timers in TS Table 3.3-3 have been revised from 2 per shutdown board to 1 per shutdown board. This revision also modifies Actions 34 and 35 of TS Table 3.3-3 to accommodate this revision to the required channels. II. REASON FOR THE PROPOSED CHANGE This revision of the trip setpoint phrase and column title, the trip setpoint inequality signs, the Av inequality representation, the term "nominal" for limiting values, and the Bases, is being proposed to support a request by NRC that TVA discontinue the use of inequalities for representing nominal trip setpoint values. This request is the result of representing setpoints that are intended to be a nominal value, with margin above and below the value, and implying that they are limits by utilizing inequality signs. This change is similar to TS changes that have been approved for the Vogtle Electric Generating Plant and Millstone Nuclear Power Station, Unit No. 3, and the initial TSs for the Watts Bar Nuclear Plant. In addition, this change is consistent with the NRC approved Technical Specification Task Force (TSTF) Item TSTF-355. The one exception to the elimination of the inequalities for trip setpoints described above is the containment purge air exhaust monitor radioactivity high value in TS Table 3.3-4 and is the result of current SQN TS configuration. Implementation of the nominal setpoint philosophy for this radiation monitor is not being requested to allow TVA to continue to set this function at a more conservative value. TVA is processing an additional TS change request to move this function from the engineered safety features E1-2

(ESF) requirements to a new specification consistent with the standard TSs that retains the inequality for these types of setpoints. Therefore, the retention of this inequality is reasonable based on the standard TS requirements and how they apply to radiation monitor functions. Avs that utilize a plus and minus representation are revised to an inequality representation to be consistent with the philosophy that Avs are limits and should utilize inequalities to properly indicate the limits. The RCP underfrequency setpoint was revised to support the accuracy of currently installed instrumentation. The underfrequency instrumentation setpoint was modified without identifying the need to revise the associated TS requirements because the new setpoint complied with the existing setpoint inequality in the TS. This error has been evaluated in accordance with the SQN Corrective Action Program. The Av was revised in accordance with the setpoint methodology as required for the associated setpoint change. This provides a more appropriate value that supports the safety limit for this function. These changes have been conservatively applied in the plant and are consistent with current TS requirements. In addition, the Av for the RCP undervoltage function has been revised to incorporate the required method for evaluating this function. The current Av is based on the TVA setpoint methodology. TVA's position is to use the Westinghouse Electric Company setpoint methodology for instrumentation functions that were originally included in the Westinghouse setpoint analysis for SQN. Since this function meets this criteria, TVA is revising the Av to a value consistent with the Westinghouse methodology. TVA evaluated the use of the TVA methodology in accordance with the Corrective Action Program because of procedural requirements that were not met for this protection function. This evaluation identified one other function that did not utilize the appropriate setpoint methodology for a portion of the analysis. The correction of this error did not result in any change to the setpoint or the Av. The trip setpoint and allowable value for the intermediate range neutron flux P-6 is proposed to be changed to provide a value that supports plant operation and will be consistent with the nominal trip setpoint methodology. SQN replaced the intermediate range channels in 1990 and revised the measurement parameters from amperes to percent E1-3

RTP. This change revised the TS requirements through Amendments 136 and 129 for SQN Units 1 and 2, respectively, to indicate the use of percent RTP. The RTP value chosen at that time was the best estimate available; however, following operating experience, it was discovered that it was not the optimum choice. Achieving the P-6 value during start-up allows the trips provided by the source range to be blocked. If this allowance occurs too early in the start-up evolution, the source range could be blocked prior to sensitive criticality events where the source range function is useful. If the source range is not blocked when P-6 is achieved, to allow use during criticality, it would result in a feature that is intended to remind the operators to block a trip function being degraded. This would be a human factors concern that could lead to an unnecessary trip of the unit. Therefore, by increasing the P-6 value to 1 x 10-4, the reminder to block the source range function will occur after critical start-up activities, but before the source range trip value, which will allow the proper operator actions at the appropriate time. The allowable value change is solely the result of the setpoint change as applied through the methodology. The revision of the trip setpoint for the fuel storage pool area radiation monitor is proposed to resolve an identified non-conservatism. During reviews of dose calculations for fuel handling accidents it was discovered that errors existed that made the current setpoint values less restrictive than required to maintain the accident analysis. TVA initiated corrective action documents and verified that settings for these monitors were acceptable to accommodate the identified errors. TVA is maintaining these monitors administratively in accordance with the Corrective Action Program until the TSs can be modified. The proposed revision will establish a new setpoint limit that will meet the corrected dose analysis. The change in minimum channels operable for the AFW and EDG loss of power timers is to provide a more appropriate requirement in consideration of the plant design. This timer function supports the actuation of the loss of power start of the AFW pumps and EDGs and load shed initiation. This function is provided by both trains of power and the voltage sensors for each train are arranged in a two-out-of-three logic scheme. Using redundant timers in each train of this function after the detection of low voltage provides a conservative design but is in excess of the required design for mitigation features. Therefore, these E1-4

timers should not have to meet single failure requirements in the TSs and only one timer is required to satisfy the loss of power start functions. The associated actions are modified to provide the appropriate wording for this change in required channels. III. SAFETY ANALYSIS Revision to Nominal Trip Setpoints The title change to "Nominal Trip Setpoint" and the removal of the inequality signs, along with the associated Bases changes, is not a change in the current application of the TSs. The SQN setpoint methodology considers the values in the trip setpoint column to be a nominal value and the calibration procedures have implemented the requirements in this manner. This is an administrative change that is intended to resolve a concern associated with using an inequality sign with a nominal value. In addition to the setpoint change, the representation of the Avs has been revised to exclusively use inequalities in place of plus and minus allowances. This change also does not change the application of the TSs. The classification of the overtemperature delta temperature T' parameter as a nominal value is not accurate with the evolution of the nominal setting philosophy utilized for reactor protection system (RPS) and ESF instrumentation. The T' is a limiting parameter for TS compliance and should not be described as a nominal value. The description of this value, as a limit with the appropriate inequalities, is the most accurate method for representation. Bases discussions provide guidance on the proper use of the nominal trip setpoint representation by indicating conditions that maintain the operability of the function and the acceptability to set functions in the conservative direction. This guidance does not alter the current application of the TSs or the intent of the TSs. Therefore, this change to the nominal trip setpoint representation will not impact plant safety because this revision of the TSs does not change the intent or application of the requirements. Reactor Coolant Pump Underfrequency Trip Setpoint and Allowable Value Revisions The setpoint revision for the RCP underfrequency function was required to address the accuracy of replacement E1-5

instrumentation. The underfrequency instrumentation setpoint was modified without identifying the need to revise the associated TS requirements because the new setpoint complied with the existing setpoint inequality in the TS. This failure has been addressed by the TVA Corrective Action Program. TVA Calculation SQN-EEB-MS-TI28-0076, Revision 4, provides the basis for the revised setpoint value. The proposed setpoint was evaluated within the calculation to ensure that erroneous reactor trips resulting from normal frequency fluctuations would not occur and that the lower safety limit of 55.8 Hz would not be impacted. An upper operational limit of 58.5 Hz was chosen primarily because the normal continuous operating frequency is 59.5 to 60.5 Hz. In accordance with SQN's Westinghouse setpoint methodology, the channel statistical allowance (CSA) for an instrumentation loop is defined by the following equation: CSA = EA+{ (PMA) 2 + (PEA)2+ (SCA+SMTE+SD) 2 + (SPE) 2 + (STE) 2 +(RCA+RMTE+RCSA+RD) 2+ (RTE) 2 } 1/2 The error terms for the above equation as defined by SQN's Westinghouse setpoint methodology are; environmental allowance (EA), process measurement accuracy (PMA), primary element accuracy (PEA), sensor calibration accuracy (SCA), sensor measurement and test equipment accuracy (SMTE), sensor drift (SD), sensor pressure effects (SPE), sensor temperature effects (STE), rack calibration accuracy (RCA), rack drift (RD), rack temperature effects (RTE), rack measurement and test equipment accuracy (RMTE), and rack calibration setting accuracy (RCSA). Since this loop only involves the relay, the above terms are evaluated for applicability. The error terms defined in the equation for the primary element and sensor are not applicable since the relay directly monitors the RCP frequency. As documented within the accuracy calculation, the relay is not subjected to harsh environmental parameters of radiation and temperature from a design basis accident. Therefore, the EA term of the equation is not applicable. From TVA Calculation SQN-EEB-MS-TI28-0076, Revision 4, the resulting rack effects (RE) portion of the CSA equation for the relay is: E1-6

RE = +/-{(RCA+RMTE+RD+RCSA)2+RTE2}1 12 RE = +/-{(0.008+(0.05+0.05)+0.553+0.05)2+0.0082}1/2 RE = +/-0.711 Hz Therefore, the error around the setpoint is 57 +/- 0.711 Hz or 57.711 Hz to 56.289 Hz. These results do not impact the lower safety limit of 55.8 Hz nor challenge the normal operational frequency of 59.5 to 60.5 Hz. The results of this calculation provide adequate verification that the installed underfrequency instrumentation will actuate within the required accident analysis assumptions to support accident mitigation. Current TVA procedures conservatively utilize the proposed 57 Hz setpoint requirement to properly maintain the associated safety limit. The Av for this function has been revised to be compatible with the proposed setpoint. This Av is defined by the Westinghouse methodology as: Av = Setpoint - the lowest of the values Ti or T2 T1 and T2 are referred to as the "trigger values" defined by SQN's Westinghouse setpoint methodology. The T1 method involves the values used in the statistical calculation as follows: T, = (RCA+RMTE+RD+RCSA) Ti = (0.008+0.1+0.553+0.05) Hz Ti = 0.771 Hz The T2 method extracts these values from the calculation and compares these numbers statistically against the total allowance as follows: T2 = TA-({A+(S)2 }1 /2+EA) where; A = (PMA) 2+(PEA) 2+ (SPE) 2+ (STE) 2 + (RTE) 2 S = (SCA+SMTE+SD) TA = Total Allowance = Setpoint - Reactor Trip Safety Limit = 57 Hz-55.8 Hz = 1.2 Hz Therefore, T2 = TA-{ (PMA)2+ (PEA)2+ (SCA+SMTE+SD)2+ (SPE)2+ (STE)2 +(RTE)2 111 2-EA As previously stated, this loop only involves a relay. The error terms defined in the equation for the process error and sensor are not applicable since the relay directly monitors the RCP frequency. The relay is located E1-7

in an auxiliary building area not subjected to harsh environmental parameters of radiation and temperature from a design basis accident. Therefore, the EA term of the equation is not applicable. This only leaves the RTE term in the equation as follows: T2 = 1.2-{(0.008)2}1i2 = 1.192 Hz The above value for T1 was found to be the most restrictive or lowest of the two values and therefore, utilized to determine Av as follows: Av = Setpoint-T1 Av = 57 Hz-0.711 Hz Av = 56.289 Hz or 56.3 Hz conservatively rounded up Although these calculations use Method 3 from American National Standards Institute (ANSI)/Instrument Society of America (ISA) S67.04, the T1 and T2 check calculations above show that the proposed setpoint and allowable value would meet the Method 1 requirements. The revised Av continues to provide assurance that the safety limit for the underfrequency reactor trip function is not impacted. TVA has verified that past calibrations for this function, with the proposed setpoint, have satisfied the new Av. Reactor Coolant Pump Undervoltage Allowable Value Revision During the setpoint evaluation for the underfrequency function, TVA identified an inconsistency in the calculation method used for the RCP undervoltage function. This method utilized a formula for calculating the Av in accordance with a methodology developed by TVA instead of the Westinghouse methodology. The TVA methodology allows two methods for calculating the Av with the one that was used for this function being less conservative than the Westinghouse method. The Av has been recalculated using the Westinghouse setpoint methodology since the loop was included in the original Westinghouse analysis. TVA's position is to use the Westinghouse methodology for instrumentation of this type. The use of TVA's methodology for this function has been evaluated by the SQN Corrective Action Program. TVA evaluated the Av for the RCP undervoltage within TVA Calculation SQN-EEB-27DAT that has been revised to resolve this concern. The error terms for this function are defined by SQN's Westinghouse setpoint methodology in the same manner as described for the underfrequency relay. El-8

These terms are utilized, along with the setpoint that has not changed, to determine the Av which is defined as: Av = Setpoint - the lowest of the values T1 or T2 T1 and T2 values were evaluated as previously described for the underfrequency function. The T1 determination is as follows: Ti = (RCA+RMTE+RD+RCSA) Ti = (0.5+0.2+0.2+0.5)% of Setpoint T, = 1.4% of Setpoint or 0.014x5022 volts alternating current (VAC) = 70.3 VAC The T2 evaluation resulted in a value of 311.76 volts and is less restrictive than the T1 value. Therefore, the Ti value was used to determine the Av as follows: Av = Setpoint-T1 Av = 5022-70.3 VAC Av = 4951.7 VAC or 4952 VAC conservatively rounded up Although these calculations use Method 3 from ANSI/ISA S67.04, the T1 and T2 check calculations above show that the proposed setpoint and allowable value would meet the Method 1 requirements. The setpoint value and associated safety limit are not affected by this change of the Av. SQN's calibration procedures have been evaluated and verified to be in compliance with the proposed Av. Intermediate Range Neutron Flux P-6 Setpoint and Allowable Value Revision The setpoint revision for the P-6 value is intended to prevent the permissive from occurring too early in the startup sequence and resulting in the operators having to delay the block of the source range reactor trip. The proposed value will ensure the ability to block the trip function at the appropriate time during the start-up evolution while continuing to optimize the availability of the source range count feature to support reactor criticality activities. Normal start-up evolutions have shown that the criticality point is usually in the range of 1 x 1o-5 to 1 x 10-4 percent RTP on the intermediate range instrumentation. The source range trip setpoint is 105 counts per second (cps) with a channel calibration tolerance that would not allow the "as left" value to be any less than 8.7 x 10 4 cps. The P-6 actuations during the past four start-ups of both SQN units, when set at 1 x 10-4 E1-9

percent RTP, have shown the value to be between 2700 and 5900 cps. These actuation values are well below the source range trip value described above and provide adequate time for the operators to block the trip function. Therefore, the proposed change to a P-6 value of 1 x 10-4 percent RTP allows the permissive to occur within or just after the normal reactor criticality range, but well before the source range trip value. The revision of the trip setpoint has been addressed in TVA Calculation SQN-EEB-PS-TI28-0001, Revision 14. This calculation is in accordance with SQN's Westinghouse setpoint methodology as stated above. The AV change to the P-6 value was only in response to the setpoint change described above. In order to maintain the setpoint methodology, this AV revision was required to be consistent with the proposed setpoint of 1 x 10-4 percent RTP. The resulting rack effects (RE) portion of the CSA equation for the instrument loop is: RE = +/-{RCA2 + RMTE2 + RCSA2+ RD2 + RTE2}1/2 RE = +/-{1.11802+0.14142+0.22362+1.87502+1.33322}1/2 RE = +/- 2.572% Decade error for the rack 2.572% channel error based on 10.3 decades full span = +/- 0.265 decades. Decade value of P-6 setpoint of 10-4% RTP is Log (10-4) = -4.0 Tech Spec Av= Setpoint + RE Using the decade values from above for setpoint and rack errors: Tech Spec Av= -4.0 -0.265 = -4.265 decades. Converting decades to % RTP: 10-4,265 = 5.43 x 10-5% RTP. The allowable value has been rounded up to 6 x 10-5% RTP, which is toward the setpoint value and therefore is conservative. The Av for this function has been revised to be compatible with the present source range setpoint. Again using the check calculation to determine a conservative allowable value T1 and T2 are calculated as: El-10

Av = Setpoint + the lowest of the values T1 or T2 T1 was used in the above calculation in deriving the allowable value. The individual parameters were squared which gives a more conservative allowable value. The T2 method extracts these values from the calculation and compares these numbers statistically against the total allowance as follows: T2 = TA- ({A+ (S)2}11/2+EA) where; A = (PMA) 2+ (PEA)2+ (SPE)2+(STE) 2+ (RTE)2 S = (SCA+SMTE+SD) TA = Total Allowance = Reactor Trip Safety Limit - Setpoint = 1.25 x 10-3% RTP - 10-4% RTP = 1.15 x 10-3% RTP Although there is no safety limit, the source range trip will be used as the Reactor Trip Safety Limit. 1.25 x 10-3% RTP - 105 cps from the source range. Therefore, T2 = TA-{ (PMA)2+(PEA) 2+(SCA+SMTE+SD)2 +(SPE)2+(STE)2 +(RTE) 2}112 -EA As previously stated, this loop only involves the rack instrumentation. The error terms defined in the equation for the process error and sensor are not applicable as both the source range and intermediate range rack instrumentation use the same detector. The instrumentation is located in an auxiliary and control building area not subjected to harsh environmental parameters of radiation and temperature from a design basis accident. Therefore, the EA term of the equation is not applicable. This only leaves the RTE term in the equation as follows: RTE = 1.3332% decade error based on 10.3 decades full span = +/- 0.13332 decades. Decade value of TA = Log (1.15 x 10-3% RTP) = -2.94 Therefore: T2 = -2.94 - 0.13332 = -3.07332 decades. Converting decades to % RTP: 10-3,07332 = 8.4 x 10-4% RTP. El-11

The above value for T1 was found to be the most restrictive or lowest of the two values and therefore, utilized to determine Av. Although these calculations use Method 3 from American National Standards Institute (ANSI)/Instrument Society of America (ISA) S67.04, the T1 and T2 check calculations above show that the proposed setpoint and allowable value would meet the Method 1 requirements. The revised Av continues to provide assurance that the permissive will be given before the source range trip occurs. TVA has verified that past calibrations for this function, with the proposed setpoint, have satisfied the new Av. Fuel Storage Pool Area Radiation Monitor Setpoint Revision The setpoint revision for the fuel storage pool area radiation monitor function was required to address identified errors in the dose calculations for a fuel handling event. The identified errors in the dose calculation have been addressed by the TVA Corrective Action Program. TVA Calculation O-RE-90-102/103, Revision 1, provides the basis for the revised setpoint value. The proposed setpoint was evaluated within the calculation to ensure that sufficient margin exists to prevent impact to the safety limit. TVA used a setpoint methodology in this calculation that was developed by TVA for instrumentation that was not included in the original Westinghouse setpoint analysis. The TVA setpoint methodology includes two methods for determining an acceptable Av similar to the T1 and T2 evaluations in the SQN's Westinghouse methodology. The TVA calculations representing the two methods are: Av(max) = Safety Limit - (LAn - LAnf) Av(min) = Setpoint + LAnf Where LAnf is defined as the Loop Normal Measurable Accuracy and includes the errors that may be detected during a calibration. These error terms include Drift, Component Accuracy, Calibration Accuracy, and Calibration Uncertainties. Whereas the LAn term also incorporates these terms in addition to terms that are not detectable during a calibration such as Process Measurement Errors. E1-12

TVA's methodology allows the use of either result or a value between the limiting Avs. For the Fuel Storage Pool Area Radiation Monitor function, a value between the limiting Avs was used. TVA has chosen to use an intermediate value based on the past history of the function. From TVA Calculation O-RE-90-102/103, Revision 1, the Fuel Storage Pool Area Radiation Monitor Safety Limit is 375.49 mR/hr. Converting the Safety Limit to volts; Safety Limit (volts) L=og[npzit(mRRlhr)] -StartingDecade

1. of Decades VoltageSpan Safety Limit (volts) 2 x [log(375.49)+1]

Safety Limit (volts) = 7.149 volts +Av = Safety Limit - (LAnBS - LAnfBS+ + Margin); Where Margin is defined as 0.158 volts or _ 25% of LAnBs+ for conservatism. +Av = 7.149 - (0.632 -0.618 + 0.158) volts +Av = 6.977 volts Converting to mR/hr: hr) [Out(voIts)X#of Decades.StardngDecade, +Av (mR/hr) = V oltageSpan +Av (mR/hr) = 10t ( 6.977 x 5 ) /10 I -1 +Av (mR/hr) = 307 mR/hr (rounded down for conservatism) The new setpoint was then determined by subtracting LAnf from this allowable value: Setpoint = +Av - Lanf Setpoint = 6.977 - 0.618 volts Setpoint = 6.359 volts Converting to mR/hr: Output (volts) X #of Decades rgeae (= 0 VoltageSpan +SJarzfngDwadel Setpoint (rnR/hr) [O10~o~) ~o eae E1-13

Setpoint (mR/hr) = 1O( 6.359 x 5 ) /10 I -1 Setpoint (mR/hr) = 151 mR/hr (rounded down for conservatism) Although these calculations are utilizing Method 3 calculations from ANSI/ISA S67.04, Method 1 calculations could have also been used and the proposed setpoint would have still been conservative because of the margin added for the setpoint and allowable value. The results of this calculation provide adequate verification that the fuel storage pool area radiation monitor will actuate within the required accident analysis assumptions to support accident mitigation. Current TVA procedures conservatively utilize a 50 mR/hr setpoint requirement to properly maintain the associated safety limit. Auxiliary Feedwater and Emergency Diesel Generator Loss of Power Timers The minimum channels operable requirement change for the AFW and 6.9-killovolt shutdown board loss of power timers is to provide a more appropriate requirement in consideration of the plant design. These timers function to support the actuation of the loss of power start of the AFW pumps and the EDGs. This function is provided by both trains of shutdown power and the voltage sensors for each train are arranged in a two-out-of-three logic scheme. Using redundant timers in each redundant train of this function, after the detection of low voltage, provides a conservative design but is in excess of the requirements for mitigation features. Therefore, multiple timers in each train should not have to meet single failure requirements in the TSs and only one timer is required to satisfy the loss of power start functions. Single failure criteria is satisfied by having actuation capability from either redundant train in the event of a loss of power condition. The associated actions for the AFW and diesel generator start and load shed on loss of power are modified to provide the appropriate wording for this change in required channels. While these changes reduce the current redundancy capability, the remaining provisions for the loss of power timers continue to fully satisfy all accident mitigation requirements associated with AFW and EDG starts and maintain single failure requirements. This change is also consistent with NUREG-1431 recommendations because multiple timers are not addressed for either of these functions. El-14

Bases Additions to Address Operability and Limiting Safety System Settings The SQN TSs have not been converted to the latest version of the standard TSs (NUREG-1431, Revision 2) and therefore, does not contain the expanded Bases found in the NUREG. For this reason, all Bases additions found in NRC approved TSTF-355, Revision 1, were not applicable for this effort. TVA has determined those that are essential to the implementation of TSTF-355 and has incorporated those into the SQN Bases. Three Bases inserts are included in this proposed TS change package that are applicable to Westinghouse design plants. The first insert provides detailed discussions associated with the application of a limiting safety system setting (LSSS) for the RPS. This insert is taken from TSTF-355 and has only been modified to include the references within the discussions as opposed to a reference section that does not exist in the current SQN TSs. The second insert includes details on the operability requirements for RPS functions using the nominal trip setpoint representation. This section is identical to the TSTF-355 discussions for this information. One sentence has been added to this insert that clarifies the conservative direction for a setpoint is in the direction of the inequality applied to the allowable value. This is consistent with the discussions included in TSTF-355 and only helps clarify the direction that would be acceptable. This will prevent any confusion in application by operating personnel. The third insert provides the same discussions as the second insert discussed above but for the ESF section of the SQN TSs. This insert also includes inserts from TSTF-355 that provide discussions associated with the use of trip setpoints and allowable values for the ESF requirements. These inserts are the equivalent of the discussions included in the second insert for the RPS functions as they would apply to ESF functions. These inserts to the SQN Bases are essential to ensuring the proper application of the nominal trip setpoint representation and the implementation of the NRC approved TSTF-355. Conclusion The proposed changes provide acceptable limits to ensure all accident mitigation and safety functions are available and capable of performing their intended function. In many cases the proposed changes implement more E1-15

conservative requirements in response to identified non-conservative TS requirements. Changes that relax current licensing basis requirements and are consistent with those in NUREG-1431 are acceptable based on the discussions provided. Overall, the proposed changes are acceptable and adequately maintain required safety functions. IV. NO SIGNIFICANT HAZARDS CONSIDERATION DETERMINATION TVA has concluded that operation of Sequoyah Nuclear Plant (SQN) Units 1 and 2, in accordance with the proposed change to the technical specifications (TSs), does not involve a significant hazards consideration. TVA's conclusion is based on its evaluation, in accordance with 10 CFR 50.91(a)(1), of the three standards set forth in 10 CFR 50.92(c). The proposed TS change will rename the "Trip Setpoint" column of reactor protection and engineered safety feature (ESF) TS tables to be "Nominal Trip Setpoint", remove the inequality signs for the trip setpoint values as appropriate, and revise the inequality representation for the allowable values (Avs) as needed. Bases discussions clarify operable conditions for the functions and prescribe conditions where the setpoints may be set more conservatively. This revision also includes the revision of other TSs that currently use the term "trip setpoint" or "nominal" that needs to be changed to be consistent with the table title. Additional changes are proposed to the TS instrumentation tables that involve the revision of three trip setpoints, three Avs, and required minimum channels operable. A. The proposed amendment does not involve a significant increase in the probability or consequences of an accident previously evaluated. The proposed revisions for the nominal trip setpoint representation are administrative changes that will not impact the application of the reactor trip or ESF actuation system instrumentation requirements. This is based on the setpoint requirements being applied without change, as well as the Avs, in accordance with the current setpoint methodology. The removal of the inequalities associated with the trip setpoint values will be more appropriate for the use of nominal setpoint values but will not differ in application from the setpoint methodology utilized by E1-16

TVA. Deletion of the nominal terminology associated with overtemperature delta temperature average temperature at rated thermal power (T') provides a better representation of the limit associated with this value. In addition, this change will not alter plant equipment or operating practices. Therefore, the implementation of these changes will not increase the probability or consequences of an accident. The revision of the reactor coolant pump (RCP) underfrequency, intermediate range neutron flux P-6, and fuel storage pool area radiation monitor trip setpoints and the Avs for the RCP underfrequeny, intermediate range neutron flux P-6, and undervoltage has been evaluated and the results are documented in approved calculations. These calculations verify that the revised values are acceptable in accordance with appropriate calculation methodologies and that they will continue to support the accident analysis. These revisions will not require changes to the instrumentation settings currently being used or the methods for maintaining them. The offsite dose potential will be reduced because the proposed TS values are more conservative and will ensure the adequacy of designed safety functions to limit the release of radioactivity. Therefore, the proposed revision of these values will not significantly increase the probability or consequences of an accident. B. The proposed amendment does not create the possibility of a new or different kind of accident from any accident previously evaluated. The revision of the nominal trip setpoint representation and elimination of the nominal nomenclature, as well as the revised setpoint values and Avs will not alter the plant configuration or functions. The revised setpoints and the proposed operability limits will continue to provide acceptable initiation of safety functions for the mitigation of postulated accidents as required by the design basis. The primary function of the reactor protection system, the ESF actuation system, and the radiation monitoring function is to initiate accident mitigation functions. These functions are not considered to be initiators of postulated accidents. The proposed changes do not create the possibility of a new or different kind of accident because the E1-17

design functions are not altered and the proposed values meet the accident analysis requirements for accident mitigation. C. The proposed amendment does not involve a significant reduction in a margin of safety. The setpoint and Av revisions proposed in this request were evaluated and found to be acceptable without impact to the safety limits required for the associated functions. The nominal trip setpoint representation change and the elimination of inappropriate nominal indications do not alter the TS functions or their application and will not require changes to design settings. Plant systems will continue to be actuated for those plant conditions that require the initiation of accident mitigation functions. The margin of safety is not reduced because the proposed conservative changes to the Av and setpoint representations will not change design functions and the initiation of accident mitigation functions for appropriate plant conditions is ensured. V. ENVIRONMENTAL IMPACT CONSIDERATION The proposed change does not involve a significant hazards consideration, a significant change in the types of or significant increase in the amounts of any effluents that may be released offsite, or a significant increase in individual or cumulative occupational radiation exposure. Therefore, the proposed change meets the eligibility criteria for categorical exclusion set forth in 10 CFR 51.22(c)(9). Therefore, pursuant to 10 CFR 51.22(b), an environmental assessment of the proposed change is not required. El-18

ENCLOSURE 2 TENNESSEE VALLEY AUTHORITY SEQUOYAH PLANT (SQN) UNITS 1 and 2 PROPOSED TECHNICAL SPECIFICATION (TS) CHANGE 02-01, REVISION 1 MARKED PAGES I. AFFECTED PAGE LIST Unit 1 2-4 2-5 2-6 2-6a 2-7 2-8 2-9 2-10 B 2-2 3/4 3-14 3/4 3-20 3/4 3-21 3/4 3-23 3/4 3-23a 3/4 3-24 3/4 3-25 3/4 3-26 3/4 3-27 3/4 3-27a 3/4 3-27b 3/4 3-28 3/4 3-40 B 3/4 3-1 Unit 2 2-4 2-5 2-6 2-7 2-8 2-9 2-10 2-11 2-12 B 2-2 3/4 3-14 3/4 3-20 3/4 3-21 3/4 3-23 3/4 3-23a 3/4 3-24 3/4 3-25 3/4 3-26 3/4 3-27 3/4 3-27a 3/4 3-27b 3/4 3-28 3/4 3-41 B 3/4 3-1 II. MARKED PAGES See attached. E2-1

INSERT 1 Technical specifications are required by 10 CFR 50.36 to contain Limiting Safety System Settings (LSSS) defined by the regulation as ". settings for automatic protective devices .. so chosen that automatic protective action will correct the abnormal situation before a Safety Limit (SL) is exceeded." The analytic limit is the limit of the process variable at which a safety action is initiated, as established by the safety analysis, to ensure that a SL is not exceeded. Any automatic protection action that occurs on reaching the analytic limit therefore ensures that the SL is not exceeded. However, in practice, the actual settings for automatic protective devices must be chosen to be more conservative than the analytic limit to account for instrument loop uncertainties related to the setting at which the automatic protective action would actually occur. The Nominal Trip Setpoint is a predetermined setting for a protective device chosen to ensure automatic actuation prior to the process variable reaching the analytic limit and thus ensuring that the SL would not be exceeded. As such, the Nominal Trip Setpoint accounts for uncertainties in setting the device (e.g., calibration), uncertainties in how the device might actually perform (e.g., repeatability), changes in the point of action of the device over time (e.g., drift during surveillance intervals), and any other factors which may influence its actual performance (e.g., harsh accident environments). In this manner, the Nominal Trip Setpoint plays an important role in ensuring that SLs are not exceeded. As such, the Nominal Trip Setpoint meets the definition of an LSSS in accordance with Regulatory Guide 1.105, Revision 3, "Setpoints for Safety-Related Instrumentation," and could be used to meet the requirements that they be contained in the technical specifications. Technical specifications contain values related to the OPERABILITY of equipment required for safe operation of the facility. OPERABLE is defined in the technical specifications as ". being capable of performing its safety function(s)." For automatic protective devices, the required safety function is to ensure that a SL is not exceeded and therefore the LSSS as defined by 10 CFR 50.36 is the same as the OPERABILITY limit for these devices. However, use of the Nominal Trip Setpoint to define OPERABILITY in technical specifications and its corresponding designation as the LSSS required by 10 CFR 50.36 would be an overly restrictive requirement if it were applied as an OPERABILITY limit for the "as found" value of a protective device setting during a surveillance. This would result in technical specification compliance problems, as well as reports and corrective actions required by the rule which are not E2-2

necessary to ensure safety. For example, an automatic protective device with a setting that has been found to be different from the Nominal Trip Setpoint due to some drift of the setting may still be OPERABLE since drift is to be expected. This expected drift would have been specifically accounted for in the setpoint methodology for calculating the Nominal Trip Setpoint and thus the automatic protective action would still have ensured that the SL would not be exceeded with the "as found" setting of the protective device. Therefore, the device would still be OPERABLE since it would have performed its safety function and the only corrective action required would be to reset the device to the Nominal Trip Setpoint to account for further drift during the next surveillance interval. Use of the Nominal Trip Setpoint to define "as found" OPERABILITY and its designation as the LSSS under the expected circumstances described above would result in actions required by both the rule and technical specifications that are clearly not warranted. However, there is also some point beyond which the device would have not been able to perform its function due, for example, to greater than expected drift. This value needs to be specified in the technical specifications in order to define OPERABILITY of the devices and is designated as the Allowable Value, which as stated above, is the same as the LSSS. The Allowable Value specified in Table 2.2-1 serves as the LSSS such that a channel is OPERABLE if the trip setpoint is found not to exceed the Allowable Value during the CHANNEL FUNCTIONAL TEST (CFT). As such, the Allowable Value differs from the Nominal Trip Setpoint by an amount primarily equal to the expected instrument loop uncertainties, such as drift, during the surveillance interval. In this manner, the actual setting of the device will still meet the LSSS definition and ensure that a Safety Limit is not exceeded at any given point of time as long as the device has not drifted.beyond that expected during the surveillance interval. Note that, although the channel is "OPERABLE" under these circumstances, the trip setpoint should be left adjusted to a value within the established trip setpoint calibration tolerance band, in accordance with uncertainty assumptions stated in the setpoint methodology (as-left criteria), and confirmed to be operating within the statistical allowances of the uncertainty terms assigned. If the actual setting of the device is found to have exceeded the Allowable Value, the device would be considered inoperable from a technical specification perspective. This requires corrective action including those actions required by 10 CFR 50.36 when automatic protective devices do not function as required. E2-3

INSERT 2 A channel is OPERABLE with a trip setpoint value outside its calibration tolerance band provided the trip setpoint "as-found" value does not exceed its associated Allowable Value and provided the trip setpoint "as-left" value is adjusted to a value within the "as-left" calibration tolerance band of the Nominal Trip Setpoint. A trip setpoint may be set more conservative than the Nominal Trip Setpoint as necessary in response to plant conditions. The conservative direction is established by the direction of the inequality applied to the Allowable Value. A detailed description of the methodology used to calculate the Allowable Value and trip setpoints, including their explicit uncertainties, is provided in the Westinghouse Electric Company setpoint methodology study which incorporates all of the known uncertainties applicable to each channel. The magnitudes of these uncertainties are factored into the determination of each trip setpoint and corresponding Allowable Value. The trip setpoint entered into the channel is more conservative than that specified by the Allowable Value (LSSS) to account for measurement errors detectable by the CFT. The Allowable Value serves as the Technical Specification OPERABILITY limit for the purpose of the CFT. One example of such a change in measurement error is drift during the surveillance interval. If the measured setpoint does not exceed the Allowable Value, the channel is considered OPERABLE. The trip setpoint is the value at which the channels are set and is the expected value to be achieved during calibration. The trip setpoint value ensures the LSSS and safety analysis limits are met for the surveillance interval selected when a channel is adjusted based on the stated channel uncertainties. Any channel is considered to be properly adjusted when the "as-left" setpoint value is within the band for CHANNEL CALIBRATION uncertainty allowance (i.e. +/- rack calibration + comparator setting uncertainties). The trip setpoint value is therefore, considered a "nominal" value (i.e., expressed as a value without inequalities) for the purposes of the CFT and CHANNEL CALIBRATION. INSERT 3 A channel is OPERABLE with a trip setpoint value outside its calibration tolerance band provided the trip setpoint "as-found" value does not exceed its associated Allowable Value and provided the trip setpoint "as-left" value is adjusted to a value within the "as-left" calibration tolerance band of the Nominal Trip Setpoint. A trip setpoint may be set more E2-4

conservative than the Nominal Trip Setpoint as necessary in response to plant conditions. The conservative direction is established by the direction of the inequality applied to the Allowable Value. The Allowable Value, in conjunction with the trip setpoint and LCO, establishes the threshold for ESF action to prevent exceeding acceptable limits such that the consequences of design bases accidents will be acceptable. The Allowable Value is considered a limiting value such that a channel is OPERABLE if the setpoint is found not to exceed the Allowable Value during the CHANNEL FUNCTIONAL TEST (CFT). Note that, although a channel is "OPERABLE" under these circumstances, the ESF setpoint must be left adjusted to within the established calibration tolerance band of the ESF setpoint in accordance with the uncertainty assumptions stated in the setpoint methodology, (as-left criteria) and confirmed to be operating within the statistical allowances of the uncertainty terms assigned. A detailed description of the methodology used to calculate the Allowable Value and ESF setpoints including their explicit uncertainties, is provided in the Westinghouse Electric Company or TVA setpoint methodology study which incorporates all of the known uncertainties applicable to each channel. The magnitudes of these uncertainties are factored into the determination of each ESF setpoint and corresponding Allowable Value. The nominal ESF setpoint entered into the channel is more conservative than that specified by the Allowable Value to account for measurement errors detectable by the CFT. The Allowable Value serves as the Technical Specification OPERABILITY limit for the purpose of the CFT. One example of such a change in measurement error is drift during the surveillance interval. If the measured setpoint does not exceed the Allowable Value, the channel is considered OPERABLE. The ESF setpoints are the values at which the channels are set and is the expected value to be achieved during calibration. The ESF setpoint value ensures the safety analysis limits are met for the surveillance interval selected when a channel is adjusted based on the stated channel uncertainties. Any channel is considered to be properly adjusted when the "as-left" setpoint value is within the band for CHANNEL CALIBRATION uncertainty allowance (i.e., calibration tolerance uncertainties). The ESF setpoint value is therefore considered a "nominal" value (i.e., expressed as a value without inequalities) for the purposes of the CFT and CHANNEL CALIBRATION. E2-5

SAFETY LIMITS AND LIMITING SAFETY SYSTEM SETTINGS 2.2 LIMITING SAFETY SYSTEM SETTINGS REACTOR TRIP SYSTEM INSTRUMENTATION SETPOINTS erator trip system instrumentation and interlocks setpoints shall be set consistent with the Trip Setpoint alues shown in Table 2.2-1. APPLICABILITY: As shown for each channel in Table 3.3-1. ACTION: With a reactor trip system instrumentation or interlock setpoint less conservative than the value shown in the Allowable Values column of Table 2.2-1, declare the channel inoperable and apply the applicable ACTION statement requirement of Specification 3.3.1 until the ch nel is restored to OPERABLE status with its trip setpoint adjusted consistent wionv March 25,1982 Amendment No. 12 SEQUOYAH - UNIT 1 2-4 E2-6

TABLE 2.2-1 REACTOR TRIP SYSTEM INSTRUMENTATION TRIP SETPOINTS FUNCTIONAL UNIT

1. Manual Reactor Trip

2. Power Range Neutron Flux

3. Power Range Neutron Flux High Positive Rate

4. Power Range Neutron Flux, High Negative Rate

5. Intermediate Range, Neutron Flux

6. Source Range Neutron Flux

7. Overtemperature AT

8. Overpower AT

9. Pressurizer Pressure-Low

10. Pressurizer Pressure-High

11. Pressurizer Water Level-High

12. Loss of Flow JJUNOMINAL ITRIP SETPOIN Not Applicable Low Setpoint 25% of RATED THERMAL POWER High Setpointl109% of RATED THERMAL POWER 195% of RATED THERMAL POWER with a time constant 2 2 second 0 5% of RATED THERMAL POWER with a time constant 2 2 second (i25% of RATED THERMAL POWER 1 105counts per second See Note 1 See Note 2 1970 psig

> 2385 psig \\ 92% of instrument span 90% of design flow per loop* ALLOWABLE VALUES Not Applicable Low Setpoint -

• 27.4% of RATED THERMAL POWER High Setpoint -
• 111.4% of RATED THERMAL POWER

< 6.3% of RATED THERMAL POWER with a time constant 2 2 second

• 6.3% of RATED THERMAL POWER with a time constant 2 2 second

< 45.20% of RATED THERMAL POWER < 1.45 x 105 counts per second See Note 3 See Note 4 2 1964.8 psig

• 2390.2 psig

< 92.7% of instrument span 2 89.6% of design flow per loop*

• Design flow is 90,045 (87,000 X 1.035) gpm per loop.

April 21, 1997 Amendment No. 44, 141, 185, 221, 223 SEQUOYAH - UNIT 1 2-5 E2-7

TABLE 2.2-1 (Continued) REACTOR TRIP SYSTEM INSTRUMENTATION TRIP SETPOINTS FUNCTIONAL UNIT

13. Steam Generator Water Level-Low-Low

a.

RCS Loops AT Equivalent to Power

• 50% RTP Coincident with Steam Generator Water Level - Low-Low (Adverse) and Containment Pressure - EAM or Steam Generator Water Level - Low-Low (EAM) with A time delay (Ts) if one Steam Generator is affected or A time delay (TM) if two or more Steam Generators are affected

b.

RCS Loop AT Equivalent to Power > 50% RTP Coincident with Steam Generator Water Level - Low-Low (Adverse) and Containment Pressure (EAM) or Steam Generator Water Level - Low-Low (EAM) MNOMINAL ALLOWABLE VALUES TRIP SETPOINT RCS Loop AT variab!ipt-4 RC Loj variable input

• 50% RTP etpo 2.5% RTP 15.0%of nrrow ange

Ž 14.% ofnarrwrag )15.0% of narrow range instrument span 0.5 psig 110.7% of narrow range instrument span T5 (Note 5) TM (Note 5) I 15.0% of narrow range 214.4% of narrow range instrument span

• 0.6 psig 2 10.1% of narrow range instrument span
• (1.01) Ts (Note 5)

< (1.01) TM (Note 5) 2 14.4% of narrow range instrument span < 0.6 psig 2 10.1% of narrow range instrument P0.5 psig 10.7% of narrow range instrument span SEQUOYAH - UNIT 1 2-6 July 24, 1991 Amendment No. 16, 85,136, 141,151 E2-8

TABLE 2.2-1 (Continued) FUNCTIONAL UNIT

14. Deleted

15. Undervoltage-Reac Coolant Pumps

16. Underfrequency-Re Coolant Pumps REACTOR TRIP SYSTEM INSTRUMENTATION TRIP SETPOINTS

) NOMINAL ALLOWABLE TRIP SETPOINT VALUES

tor

,actor e3 5022 volts-each bus - each bus Ž47 2 volt ach bus 56.3 Ž5&. - each bus

17. Turbine Trip A. Low Trip System Pressure B. Turbine Stop Valve Closure 45 psig 1% open 2 43 psig 2 1% open

18. Safety Injection Input from ESF Not Applicable Not Applicable

19. Intermediate Range Neutron Flux - (P-6) Enable Block Source Range Reactor Trip

20. Power Range Neutron Flux (not P-10) Input to Low Power Reactor Trips Block P-7 10^

\\>21 x 40-% of RATED 1HERMAL POWER Q 10% of RATED THERMAL < 12.4% of RATED POWER THERMAL POWER SEQUOYAH - UNIT 1 May 16,1990 Amendment No. 16, 85, 136, 141 2-6a E2-9

TABLE 2.2-1 (Continued) REACTOR TRIP SYSTEM INSTRUMENTATION TRIP SETPOINTS FUNCTIONAL UNIT

21. Turbine Impulse Chamber Pressure -

(P-13) Input to Low Power Reactor Trips Block P-7

22. Power Range Neutron Flux - (P-8) Low Reactor Coolant Loop Flow, and Reactor Trip

23. Power Range Neutron Flux - (P-10) -

Enable Block of Source, Intermediate, and Power Range (low setpoint) Reactor Trips

24. Reactor Trip P-4

25. Power Range Neutron Flux - (P-9) -

Blocks Reactor Trip for Turbine Trip Below 50% Rated Power 10% Turbine Impulse t ressure Equivalent 35% of RATED THERMAL POWER 10% of RATED THERMAL POWER Not Applicable 50% of RATED THERMAL POWER ALLOWABLE VALUES

• 12.4% Turbine Impulse Pressure Equivalent
• 37.4% of RATED THERMAL POWER 2 7.6% of RATED THERMAL POWER Not Applicable
• 52.4% of RATED THERMAL POWER NOTATION NOTE 1:

Overtemperature AT ( I + T4S) m a ~+s DS < ATo {Ki K(1 + A S) 1 + T2S) - PF) - f. (Al)} Where: I + T4S I + T5S = Lead-lag compensator on measured AT Time constants utilized in the lead-lag controller for AT, T4 2 5 secs, If,< 3 sec. = Indicated AT at RATED THERMAL POWER 1.15 0.011 ATo K1 K2 September 15, 1995 Amendment No. 19, 114, 141, 211 SEQUOYAH - UNIT I 2-7 E2-10

TABLE 2.2-1 (Continued) REACTOR TRIP SYSTEM INSTRUMENTATION TRIP SETPOINTS NOTATION (Continued) NOTE 1: (Continued) I + -rS 1 + T2S The function generated by the lead-lag controller for Ta, dynamic compensation Time constants utilized in the lead-lag controller for Tavg, Ad 33 secs., 2

• 4 secs.

T = Average temperature 0F 578.20 t RATED THERMAL POWER) = 0.00055 K3 P Pressurizer pressure, psig pt = 2235 psig (Nominal RCS operating pressure) S Laplace transform operator (sec 1) and f1 (Al) is a function of the indicated difference between top and bottom detectors of the power-range nuclear ion chambers; with gains to be selected based on measured instrument response during plant startup tests such that: (i) for qt - qb between QTNL* and QTPL* f, (AI) = 0 (where qt and qb are percent RATED THERMAL POWER in the top and bottom halves of the core respectively, and qt + qb is total THERMAL POWER in percent of RATED THERMAL POWER). April 21, 1997 Amendment No. 19,141, 211, 223 SEQUOYAH - UNIT 1 2-8 E2-11

TABLE 2.2-1 (Continued) REACTOR TRIP SYSTEM INSTRUMENTATION TRIP SETPOINTS NOTATION (Continued) NOTE 1: (Continued) (ii) (iii) nominal for each percent that the magnitude of (qt - qb) exceeds QTNLh e shall be automatically reduced by QTNS of its value at RATED THERMAL POWER. for each percent that the magnitude of (qt - qb) exceeds QTPL A i n shall be automatically reduced by QTPS of its value at RATED THERMAL POWER. NOTE 2: Overpower AT 1 + T S

• ATO {K4 - K5(1T3S ) T-K 6 (T-T")- f2 (AI)}

Where: 1 + T4S = as defined in Note I 1 + -rS 27 'z -r as defined in Note I ATO = as defined in Note 1 K4 1.087 KS 2 0.02fF for increasing average temperature and 0 for decreasing average temperature T3S = The function generated by the rate-lag controller for T9, 1 + T3S dynamic compensation QTNL, QTPL, QTNS, and QTPS are specified in the COLR per Specification 6.9.1.14. April 21, 1997 Amendment No. 19, 114, 141, 211, 223 SEQUOYAH - UNIT I 2-9 E2-12

TABLE 2.2-1 (Continued) REACTOR TRIP SYSTEM INSTRUMENTATION TRIP SETPOINTS NOTATION (Continued') NOTE 2: (Continued) Time constant utilized in the rate-lag controller for Tavg, T 2* 10 secs. 3 3 K 2 0.0011 for T >T" and K 2 0 for T < T" 6 6 T = as defined in Note 1 O

• Indicated Tavg at RATED THERMAL POWER (Calibration temperature for AT instrumentation, < 578.20F)

S = as defined in Note 1 and f2(AI) is a function of the indicated difference between top and bottom detectors of the power-range nuclear ion chambers; with gains to be selected based on measured instrument response during plant startup tests such that: (i) for qt - qb between QPNL* and QPPL* f2(AI) = 0 (where qt and qb are percent RATED THERMAL POWER in the top and bottom halves of the core respectively, and qt + qt is total THERMAL POWER in percent of RATED THERMAL POWER). (ii) nominal for each percent that the magnitude of (qt - qb) exceeds QPNL* the l setpoint shall be automatically reduced by QPNS* of its value at RATED THERMAL POWER. (iii) for each percent that the magnitude of (qt - qb) exceeds QPP setpoint shall be automatically reduced by QPPS* of its value at RATED THERMAL POWER. nominal J J set NOTE 3: The channel's maximum trip setpoint shall not exceed its mputed trip poin by more than 1.9 percent AT span. nominal J set NOTE 4: The channel's maximum trip setpoint shall not exceed i computed trip point y more than 1.7 percent AT span.

• QPNL, QPPL, QPNS, and QPPS are specified in the COLR per Specification 6.9.1.14.

April 21, 1997 SEQUOYAH - UNIT 1 2-10 Amendment No. 19, 141, 211, 223 E2-13

SAFETY LIMITS BASES These limiting heat flux conditions are higher than those calculated for the range of all control rods fully withdrawn to the maximum allowable control rod insertion assuming the axial power imbalance is within the limits of the f, (Delta 1) function of the Overtemperature Delta T trip. When the axial power imbalance is not within the tolerance, the axial power imbalance effect on the Overtemperature Delta T trips will reduce the setpoints to provide protection consistent with core safety limits. 2.1.2 REACTOR COOLANT SYSTEM PRESSURE The restriction of this Safety Limit protects the integrity of the Reactor Coolant System from overpressurization and thereby prevents the release of radionuclides contained in the reactor coolant from reaching the containment atmosphere. The reactor pressure vessel and pressurizer are designed to Section III of the ASME Code for Nuclear Power Plant which permits a maximum transient pressure of 110% (2735 psig) of design pressure. The Reactor Coolant System piping, valves and fittings, are designed to ANSI B 31.1 1967 Edition, which permits a maximum transient pressure of 120% (2985 psig) of component design pressure. The Safety Limit of 2735 psig is therefore consistent with the design criteria and associated code requirements. The entire Reactor Coolant System is hydrotested at 3107 psig, 125% of design pressure, to demonstrate integrity prior to initial operation. 2.2.1 REACTOR TRIP SYSTEM INSTRUMENTATION SETPOINTS Nominal ThdbReactor Trip Setpoint Limits specifie in Table 2.2-1 are the values at which the Reactor Trips 4J Nominal are set for each functional unit. the Trip Setpoinhave been selected to ensure that the reactor core and reactor coolant system are prevented fromxing eir safety limits during normal operation and design basis anticipated operational occurrences and to assist the Engineered Safety Features Actuation System in mal mitigating the consequences of accidents. Operation with a trip set less conservative than its Trip Setpoint UNiominaliJ but within its specified Allowable Value is acche basis that the difference bet achT point and the Allowable Value is equal to or less s the a oa ce assumed for each trip in the A_ ~ft rackj' safety analyses. AddInsert2 Bases Change SEQUOYAH -UNIT 1 B 2-2 Revised: 08/18/87 E2-14

INSTRUMENTATION 3/4.3.2 ENGINEERED SAFETY FEATURE ACTUATION SYSTEM INSTRUMENTATION LIMITING CONDITION FOR OPERATION 3.3.2.1 The Engineered Safety Feature Actuation System (ESFAS) instrumentation channels and interlocks shown in Table 3.3-3 shall be OPERABLE with their trip setpoints set consistent with the values shown in column of Table 3.3-4. Nominal APPLICABiti-P6, n in Table 3.3-3. ACTION:

a.

With an ESFAS instrumentation channel or interlock trip setpoint less conservative than the value shown in the Allowable Values column of Table 3.3-4, declare the channel inoperable and apply the applicable ACTION requirement of Table 3.3-3 until the channel is restored to OPERABLE status with the trip setpoint adjusted consistent with r valualue. < n Nominal

b.

With an ESFAS instrumentation channel or interlock inoperable, tag shown in Table 3.3-3. SURVEILLANCE REQUIREMENTS 4.3.2.1.1 Each ESFAS instrumentation channel shall be demonstrated OPERABLE by the performance of the CHANNEL CHECK, CHANNEL CALIBRATION and CHANNEL FUNCTIONAL TEST operations for the MODES and at the frequencies shown in Table 4.3-2. 4.3.2.1.2 The logic for the interlocks shall be demonstrated OPERABLE during the automatic actuation logic test. The total interlock function shall be demonstrated OPERABLE at least once per 18 months during CHANNEL CALIBRATION testing of each channel affected by interlock operation. 4.3.2.1.3 The ENGINEERED SAFETY FEATURES RESPONSE TIME of each ESFAS function shall be verified to be within the limit at least once per 18 months. Each verification shall include at least one train such that both trains are verified at least once per 36 months and one channel per function such that all channels are verified at least once per N times 18 months where N is the total number of redundant channels in a specific ESFAS function as shown in the "Total No. of Channels" Column of Table 3.3-3. February 29, 2000 Amendment No. 190, 251 SEQUOYAH - UNIT 1 3/4 3-14 E2-15

TABLE 3.3-3 (Continued) ENGINEERED SAFETY FEATURE ACTUATION SYSTEM INSTRUMENTATION TOTAL NO. OF CHANNELS CHANNELS TO TRIP MINIMUM CHANNELS OPERABLE APPLICABLE MODES FUNCTIONAL UNIT

e. Loss of Power Start ACTION

1. Voltage Sensors

2. Load Shed Timer

f. Trip of Main Feedwater Pumps Start Motor-Driven Pumps and Turbine Driven Pump 3/shutdown board 2/shutdown board 1/pump 2/shutdown board 1/shutdown board 1/pump 3/shutdown utdown]

1/pump 1, 2, 3 1, 2, 3 1, 2 35 35 20*

g. Auxiliary Feedwater Suction Pressure-Low

h. Auxiliary Feedwater Suction Transfer Time Delays 3/pump 2/pump 3/pump 1, 2, 3 21*

1. Motor-Driven Pump

2. Turbine-Driven Pump

• • Unit I shutdown boards only 1/pump 2/pump 1/pump 1/pump 1/pump 2/pump 1, 2, 3 1, 2, 3 21*

21* SEQUOYAH - UNIT 1 3/4 3-20 August 22, 1995 Amendment No. 41, 129, 182,188, 207 E2-16

TABLE 3.3-3 (Continued) ENGINEERED SAFETY FEATURE ACTUATION SYSTEM INSTRUMENTATION TOTAL NO. OF CHANNELS CHANNELS TO TRIP MINIMUM CHANNELS OPERABLE APPLICABLE MODES FUNCTIONAL UNIT ACTION

7. LOSS OF POWER

a. 6.9 kv Shutdown Board -

Loss of Voltage

1. Voltage Sensors

2. Diesel Generator Start and Load Shed Timer 3/shutdown board 2/shutdown board 2/shutdown board 1/shutdown board 3/shutdown board 2/shutdown board 1

,3H# 5a: 62x 34 34

b. 6.9 kv Shutdown Board Degraded Voltage

1.

Voltage Sensors

2. Diesel Generator Start and Load Shed Timer

3. SI/Degraded Voltage Logic Enable Timer 3/shutdown board 2/shutdown board 2/shutdown board 2/shutdown 3/shutdown board board 1/shutdown 2/shutdown board board 1/shutdown 2/shutdown board board 5 iwt## 6ki 1,2,3 4 5##, 6 i 1, 2, 3,4 34 34 34

8. ENGINEERED SAFETY FEATURE ACTUATION SYSTEM INTERLOCKS

a. Pressurizer Pressure-P-1I/Not P-11

b. Deleted

c. Steam Generator Level P-14 3

2 2 1, 2, 3 22a 3/oop 2/loop any loop 3/loop

1. 2 22c SEQUOYAH - UNIT 1 3/4 3-21 August 22, 1995 Amendment No. 41,129, 141, 160, 182, 188, 207 E2-1 7

TABLE 3.3-3 (Continued) ACTION 21 - ACTION 22 - With less than the Minimum Number of Channels OPERABLE, declare the associated auxiliary feedwater pump inoperable, and comply with the ACTION requirements of Specification 3.7.1.2. With less than the Minimum Number of Channels OPERABLE, declare the interlock inoperable and verify that all affected channels of the functions listed below are OPERABLE or apply the appropriate ACTION statement(s) for those functions. Functions to be evaluated are:

a.

Safety Injection Pressurizer Pressure Steam Line Pressure Negative Steam Line Pressure Rate

b.

Deleted

c.

Turbine Trip Steam Generator Level High-High Feedwater Isolation Steam Generator Level High-High ACTION 23 - ACTION 24 - ACTION 25 - ACTION 34 - With the number of OPERABLE channels one less than the Total Number of Channels, be in at least HOT STANDBY within 6 hours and in at least HOT SHUTDOWN within the following 6 hours; however, one channel may be bypassed for up to 2 hours for surveillance testing per Specification 4.3.2.1.1. With the number of OPERABLE channels one less than the Total Number of Channels, restore the inoperable channel to OPERABLE status within 48 hours or be in at least HOT STANDBY within 6 hours and in at least HOT SHUTDOWN within the following 6 hours. With the number of OPERABLE channels one less than the Total Number of Channels, restore the inoperable channel to OPERABLE status within 48 hours or declare the associated valve inoperable and take the ACTION required by Specification 3.7.1.5.

a.

With the number of OE Echannels one less than the Total Number of t ~U for voltage sensors C sresoraten l annel to OPERABLE status within 6 hours or enter applicable Limiting Condition(s) For Operation and Action(s) for the associated diesel generator set made inoperable by the channel.

b.

With the number of OPERABI E channels less D-I t oa Number of ) U for voltage sensors or timers Channels by more than one, restore all but one channel t ERABLE status within 1 houro For Operation and Action(s) for the associated diesel generator set made inoperable by the channels. SEQUOYAH - UNIT 1 3/4 3-23 August 22, 1995 Amendment No. 12,63, 129,141, 160,182,188, 207 E2-1 8

TABLE 3.3-3 (Continued) ACTION 35 -

a.

With the number of OPERABLE channels one less than the Total , -for voltage sensors of C els restore the inoerable hannel to OPERABLE status within ours or enter applicablem gCondition(s) For Operation and Action(s) for the associated auxiliary feedwater pump made inoperable by the channel.

b.

With the number of less tha th otal Number for voltage sens or timer of Channels by more tha e, restore all but one channel to ERABLE status within 1 hour or enter appca ing Conition or Operation and Action(s) for the associated auxiliary feedwater pump made inoperable by the channels. ACTION 36 - With the number of OPERABLE channels one less than the Total Number of Channels, STARTUP and/or POWER OPERATION may proceed provided the following conditions are satisfied:

a.

The inoperable channel is placed in the tripped condition within 6 hours.

b.

For the affected protection set, the Trip Time Delay for one affected steam generator (Ts) is adjusted to match the Trip Time Delay for multiple affected steam generators (TM) within 4 hours.

c.

The Minimum Channels OPERABLE requirement is met; however, the inoperable channel may be bypassed for up to 4 hours for surveillance testing of other channels per Specification 4.3.2.1.1. ACTION 37 - ACTION 38 - With the number of OPERABLE channels one less than the Total Number of Channels, STARTUP and/or POWER OPERATION may proceed provided that within 6 hours, for the affected protection set, the Trip Time Delays (Ts and TM) threshold power level for zero seconds time delay is adjusted to 0% RTP. With the number of OPERABLE channels one less than the Total Number of Channels, STARTUP and/or POWER OPERATION may proceed provided that within 6 hours, for the affected protection set, the Steam Generator Water Level - Low-Low (EAM) channels trip setpoint is adjusted to the same value as Steam Generator Water Level - Low-Low (Adverse). SEQUOYAH - UNIT 1 3/4 3-23a August 22, 1995 Amendment No. 141,160,182, 188, 207 E2-1 9

TABLE 3.3-4 ENGINEERED SAFETY FEATURE ACTUATION SYSTEM INSTRUMENTATION TRIP SETPOINTS FUNCTIONAL UNIT

1. SAFETY INJECTION, TURBINE TRIP AND FEEDWATER ISOLATION

a.

Manual Initiation

b. Automatic Actuation Logic

c.

Containment Pressure-High

d. Pressurizer Pressure-Low

e. Deleted

f.

Steam Line Pressure-Low Not Applicable Not Applicable 1.54 psig )1870 psig

00 psig steam line pressure (Note 1)

ALLOWABLE VALUES Not Applicable Not Applicable

• 1.6 psig 2 1864.8 psig 2 592.2 psig steam line pressure (Note 1)

SEQUOYAH - UNIT 1 3/4 3-24 May 16, 1990 Amendment No. 141 E2-20

TABLE 3.3-4 (Continued) ENGINEERED SAFETY FEATURE ACTUATION SYSTEM INSTRUMENTATION TRIP SETPOINTS FUNCTIONAL UNIT

2.

CONTAINMENT SPRAY

a. Manual Initiation

b. Automatic Actuation Logic

c. Containment Pressure-High-High

3. CONTAINMENT ISOLATION

a. Phase "A" Isolation

1. Manual

2. From Safety Injection Automatic Actuation logic

b. Phase "B" Isolation

1.

Manual

2. Automatic Actuation Logic

3. Containment Pressure-High-High

c. Containment Ventilation Isolation

1.

Manual

2. Automatic Isolation Logic Not Applicable Not Applicable 32.81 psig Not Applicable Not Applicable Not Applicable Not Applicable

[f2.81 psig Not Applicable Not Applicable ALLOWABLE VALUES Not Applicable Not Applicable

• 2.9 psig Not Applicable Not Applicable Not Applicable Not Applicable
• 2.9 psig Not Applicable Not Applicable May 16, 1990 Amendment No. 12, 141 SEQUOYAH - UNIT I 3/4 3-25 E2-21

TABLE 3.3-4 (Continued) ENGINEERED SAFETY FEATURE ACTUATION SYSTEM INSTRUMENTATION TRIP SETPOINTS FUNCTIONAL UNIT NOMINAL ALLOWABLE VALUES TRIP SETPOINT

3. Containment Purge Air Exhaust Monitor Radioactivity-High

4.

STEAM LINE ISOLATION

a.

Manual

b. Automatic Actuation Logic

c.

Containment Pressure-High-High

d.

Steam Line Pressure-Low

e. Negative Steam Line Pressure Rate-High

5. TURBINE TRIP AND FEEDWATER ISOLATION

a. Steam GeneratorWater level-High-High

b.

Automatic Actuation Logic

• 8.5 x 10 3

<Ci/cc s 8.5 x 10 3 pCi/cc Not Applicable Not Applicable q 2.81 psig 0600 psig steam line pressure N4ote 1) Not Applicable Not Applicable

• 2.9 psig

Ž 592.2 psig steam line pressure (Note 1)

• 107.8 psi (Note 2)
• 81.7% of narrow range instrument span each steam generator N.A.

481% of narrow range instrument span each steam generator N.A. June 25, 1993 Amendment No. 63,141, 168 SEQUOYAH - UNIT 1 3/4 3-26 E2-22

TABLE 3.3-4 (Continued) ENGINEERED SAFETY FEATURE ACTUATION SYSTM INSTRUMENTATION TRIP SETPOINTS FUNCTIONAL UNIT / JNOMINAL ALLOWABLE VALUES TRIP SETPOIN

6. AUXILIARY FEEDWATER

a.

Manual Not Applicable

b. Automatic Actuation Logic Not Applicable

c.

Main Steam Generator Water Level-Low-Low I. RCS Loop AT Equivalent to RCS Loop AT variable inpq3 Power S 50% RTP 50% RTP Coincident with Steam 15.0% of narrow range Generator Water Level-Low-instrument span Low (Adverse) and Containment Pressure-EAM 0.5 psig or Not Applicable Not Applicable n#omial RCS Loop AT iP p setpoint +2.5% RTP 214.4% of narrow range instrument span < 0.6 psig 2 10.1% of narrow instrument span S (1.01) TS (Note 5, Table 2.2-1) < (1.01) Tm (Note 5, Table 2.2-1) Steam Generator Water Level-Low-Low (EAM) with A time delay (TS) if one Steam Generator is affected or A time delay (Tm) if two or < more Steam Generators are affected 0.7% of narrow range ITS (Note 5, Table 2.2-1) ITm (Note 5, Table 2.2-1) July 24, 1991 Amendment No. 29, 94, 141, 151 SEQUOYAH - UNIT 1 3/4 3-27 E2-23

TABLE 3.3-4 (Continued) FUNCT ENGINEERED SAFETY FEATURE ACTUATION SYSTEM INSTRUMENTATION TRIP SETPOINTS IONAL UNIT INOMINAL ALLOWABLE VALUES TRIP SETPOINT ii. RCS Loop AT Equivalent to Power > 50% RTP Coincident with Steam Generator 5.0% of narrow range Water Level-Low-Low (Adverse) rtinstrument span and Containment Pressure (EAM) or 2 14.4% of narrow range instrument span < 0.6 psig 2 10.1% of narrow range instrument span Steam Generator Water Level-1,,.iO.7% of narrow range Low-Low (EAM) instrument span

d. S.I.

See I above (all SI Setpoints)

e.

Loss of Power Start

1. Voltage Sensors

2. Load Shed Timer

f. Trip of Main Feedwater Pumps G5520 volts 1.25 seconds N.A.

volts 4 > 1.00 second and 442r, 0-2-5 seconds

g. Auxiliary Feedwater Suction Pressure- /

Low -k

h. Auxiliary Feedwater Suction Transfer Time Delays 3.21 psig (motor driven 2 2.44 psig (motor driven jump) pump) 513.9 psig (turbine driven 2 12 psig (turbine driven (pump) 5 44seconds 4 seconds (motor driven

Ž 3.6 seconds pump) l4 eoconds +0.1 (motor driven pump) sBGonds S6.05 seconds 5.5 seconds (turbine driven Ž4.95 seconds pump) 5.5 eoconds +0.55 \\_ neGnds(turbine driven pump) March 1, 1996 Amendment No. 29, 94,129, 141, 151, 182,183, 188, 207,219 SEQUOYAH - UNIT 1 3/4 3-27a E2-24

TABLE 3.3-4 (Continued) ENGINEERED SAFETY FEATURE ACTUATION SYSTEM INSTRUMENTATION TRIP SETPOINTS FUNCTIONAL UNIT JNOMINAL ALLOWABLE VALUES TRIP SETPOINT

7.

LOSS OF POWER

a. 6.9 kv Shutdown Board Undervoltage Loss of Voltage

1. Voltage Sensors 5

vots 2 5331 volts A2 1.00 seconds and 51.50

2. Diesel Generator Start and Load Shed 1.25 seconds 1.25 l 0.25 seconds Timer

b. 6.9 kv Shutdown Board-Degraded Voltage

1. Voltage SensorsI/

6456 volts l 6403.5 volts (dropout)

• 6595.5 volts (reset)

2. Diesel Generator Start and Load Shed

'-300 seconds < 370 seconds Timer i, 2 7.5 seconds and 511.5

3. SI/Degraded Voltage Logic 9.5 seconds 2

9.54+0 seconds Enable Timer

8.

ENGINEERED SAFETY FEATURE ACTUATION SYSTEM INTERLOCKS

a. Pressurizer Pressure

1. Not P-11, Automatic Unblock of Safety Injection on Increasing Pressure

2. P-11, Enable Manual Block of Safety Injection on Decreasing Pressure 1970 psig 1962 psig

< 1975.2 psig 2 1956.8 psig SEQUOYAH - UNIT I 3/4 3-27b March 1, 1996 Amendment No. 33, 129, 141, 182, 188, 207, 219 E2-25

TABLE 3.3-4 (Continued) ENGINEERED SAFETY FEATURE ACTUATION SYSTEM INSTRUMENTATION TRIP SETPOINTS FUNCTIONAL UNIT tINOMINAL ALLOWABLE VALUES LTRIP SETPOINT

8. ENGINEERED SAFETY FEATURE ACTUATION SYSTEM INTERLOCKS (Continued)

b.

Deleted

c. Deleted

d. Steam Generator Level Turbine Trip, (See 5. above)

Feedwater Isolation P-14

9. AUTOMATIC SWITCHOVER TO CONTAINMENT SUMP 52 from tank base 4 a1 127.29"

a. RWST Level -Low 130" from tank base 130" +/- 2.71" from tank bas COINCIDENT WITH S31.68" above elev. 680' Containment Sump Level - High 30" above elev. 680' J Ž28.32" AND Safety Injection 3

302 a 1.68" above elev. 680' ( (See I above for all Safety Injection Setpoints/Allowable Values)

b. Automatic Actuation Logic N.A.

N.A. Note 1: Time constants utilized in the lead-lag controller for Steam Pressure - Low are ti 2 50 seconds and r2 < 5 seconds. Note 2: Time constant utilized in the rate-lag controller for Negative Steam Line Pressure Rate - High is X 2 50 seconds. May 16, 1990 Amendment No. 14, 63, 141 SEQUOYAH - UNIT 1 314 3-28 E2-26

TABLE 3.3-6 RADIATION MONITORING INSTRUMENTATION MINIMUM CHANNELS OPERABLE APPLICABLE MODES ALARM/TRIP SETPOINT MEASUREMENT RANGE ACTION INSTRUMENT

1. AREA MONITOR

a. Fuel Storage Pool Area

2.

PROCESS MONITORS

a.

Containment Purge Air 1 C at1 -1 4 < 200mRhr 1 0 -104 mR/hr 26 28 1 1,2,3,4&6 < 8.5x 10 3 pCi/cc 10- 107 cpm

b. Containment

i. Gaseous Activity RCS Leakage Detection 1

1,2,3&4 N/A 10 - 107 cpm 27 ii. Particulate Activity RCS Leakage Detection 1 1,2,3&4 N/A 10 - 107 cpm 27

c. Control Room Isolation 2

ALL MODES and during movement of irradiated fuel assemblies < 400 cpm** 10 - 107 cpm 29

• With fuel in the storage pool or building
  • Equivalent to 1.0 x 10 5pCi/cc.

May 31, 2000 Amendment No. 12, 60, 112,168, 256 SEQUOYAH - UNIT 1 3/4 3-40 E2-27

3/4.3 INSTRUMENTATION BASES 3/4.3.1 and 3/4.3.2 PROTECTIVE AND ENGINEERED SAFETY FEATURES (ESF) INSTRUMENTATION The OPERABILITY of the protective and ESF instrumentation systems and interlocks ensure that

1) the associated ESF action and/or reactor trip will be init en thea eter nominal trip monitored by each channel or combination thereof reache ts setpoint, 2) the s ecifie incidence logic is maintained, 3) sufficient redundancy is maintained to pert-iar neeout ofrvice for testing or maintenance, and 4) sufficient system functional capability is available for protective and ESF purposes from diverse parameters.

The OPERABILITY of these systems is required to provide the overall reliability, redundancy and diversity assumed available in the facility design for the protection and mitigation of accident and transient conditions. The integrated operation of each of these systems is consistent with the assumptions used in the accident analyses. The Engineered Safety Features System interlocks perform the functions indicated below on increasing the required parameter, consistent with Table 3.3-4: L~tnominal trip P-11 Defeats the manual block of safety injection ion on ow pressurizer pressure. P-14 Trip of all feedwater pumps, turbine trip, closure of feedwater isolation valves and inhibits feedwater control valve modulation. On decreasing the required parameter the opposite function is performed at reset setpoints. The surveillance requirements specified for these systems ensure that the overall system functional capability is maintained comparable to the original design standards. The periodic surveillance tests performed at the minimum frequencies are sufficient to demonstrate this capability. The surveillance for the comparison of the incore to the excore Axial Flux Difference is required only when reactor power is 2 15 percent. The 96 hour delay in the first performance of the surveillance after reaching 15 percent reactor thermal power (RTP), following a refueling outage, is to achieve a higher power level and approach Xenon stability. The surveillance is typically performed when the RTP is 2 30 percent to ensure the results of the evaluation are more accurate and the adjustments more reliable. The frequency of 31 EFPD is to allow slow changes in neutron flux to be better detected during the fuel cycle. May 30, 1995 SEQUOYAH - UNIT 1 B 3/4 3-1 Amendment No. 141,199 E2-28

SAFETY LIMITS AND LIMITING SAFETY SYSTEM SETTINGS 2.2 LIMITING SAFETY SYSTEM SETTINGS REACTOR TRIP SYSTEM INSTRUMENTATION SETPOINTS 2.2.1 The reactor trip system instrumentation and interlocks setpoints shall be set consistent with 5Vie pvalues shown in Table 2.2-1. APPLICABILITY: As shown for each channel in Table 3.3-1. ACTION: With a reactor trip system instrumentation or interlock setpoint less conservative than the value shown in the Allowable Values column of Table 2.2-1, declare the channel inoperable and apply the applicable ACTION statement requirement of Specification 3.3.1 until the channel is restored to OPERABLE status with its trip setpoint adjusted consistent with t r p SEQUOYAH - UNIT 2 2-4 E2-29

FUNCTIONAL UNIT

1. Manual Reactor Tri

2. Power Range Neut Flux

3. Power Range Neut Flux High Positive Rate

4. Power Range Neut High Negative Rat(

TABLE 2.2-1 REACTOR TRIP SYSTEM INSTRUMENTATION TRIP SETPOINTS NOMINA ALLOWABLE VALUES p Not Applicable Not Applicable ron Low Setpoint 125% of RATED Low Setpoint - < 27.4% of RATED THERMAL POWER THERMAL POWER High Setpoint: 109% of High Setpoint - < 111.4% of RATED RATED THERMAL POWER THERMAL POWER ron 15% of RATED THERMAL < 6.3% of RATED THERMAL POWER with a time constant Ž 2 POWER with a time constant Ž 2 second second ron Flux, 0 5% of RATED THERMAL < 6.3% of RATED THERMAL POWER with a time constant Ž 2 POWER with a time constant Ž 2 second second e, Neutron [D25% of RATED THERMAL < 45.20% of RATED THERMAL POWER POWER 1tron a 105 counts per second < 1.45 x 105 counts per second IT See Note 1 See Note 3 See Note 2 See Note 4 ire-Low 1970 psig 2 1964.8 psig ire-High 385 psig < 2390.2 psig Level-High \\ 2% of instrument span < 92.7% of instrument span -90% of design flow per loop* 2 89.6% of design flow per loop*

5. Intermediate Rangi Flux

6. Source Range Neu Flux

7. Overtemperatureb

8. Overpower AT

9. Pressurizer Pressu

10. Pressurizer Pressu

11. Pressurizer Water

12. Loss of Flow

• Design flow is 90,045 (87,000 X 1.035) gpm per loop.

April 21, 1997 Amendment No. 36, 132, 177, 203, 212, 214 SEQUOYAH - UNIT 2 2-5 E2-30

TABLE 2.2-1 (Continued) REACTOR TRIP SYSTEM INSTRUMENTATION TRIP SETPOINTS JJNOMINAL 'IT TRIP SETPOINT ALLOWABLE Vs FUNCTIONAL UN 'ALUES A -M Lvl. -Lowa %ene-Lor water Level-Low-Low or Wit

a.

RCS Loop AT Equivalent to Power < 50% RTP Coincident with Steam Generator Water Level-Low-Low (Adverse) and Containment Pressure (EAM) Steam Generator Water Level-Low-Low (EAM) h A time delay (Ts) if one Steam Generator is affected A time delay (Tm) if two or more Steam Generators are affected 5.0% of narrow range .5 psig RCS Loop AT variabl t 50% RTP ariable input trip setpoint .5% RTP 2 14.4% of narrow range instrument span < 0.6 psig 2 10.1% of narrow range instrument span < (1.01) Ts (Note 5) < (1.01)Tm (Note 5) (Note 5) or Note 5) October 31, 1990 2-6 Amendment Nos. 7,132 SEQUOYAH - UNIT 2 E2-31

TABLE 2.2-1 (Continued) REACTOR TRIP SYSTEM INSTRUMENTATION TRIP SETPOINTS JNOMINAL JIT TRIP SETPOINT ALLOWABLE VALUES FUNCTIONAL UN D. K(CS Loop A I Equivalent to Power > 50% RTP or

14. Dele

15. Undi Cool

16. Undo Cool

17. Turb A. I B.;

Coincident with Steam Generator Water 5.0% of narrow range Level-Low-Low(Adverse) instrument span and Containment Pressure .5 psig (EAM) Steam Generator Water 0.70.7% of narrow range Level-Low-Low (EAM) instrument span ?ted arvoltage-Reactor 022 volts-each bus ant Pumps Brfrequency-Reactor5 lant Pumps of H z each bus ine Trip Low Trip System -5 psig Pressure Turbine Stop Valve - 1% open Closure 214.4% of narrow range instrument span < 0.6 psig ? 10.1% of narrow range instrument span 2-4739 volt - each bus 56.3 P Hz each bus 2 43 psig > 1% open

18. Safety Injection Input from ESF Not Applicable Not Applicable October 31, 1990 Amendment Nos. 7, 76,132 SEQUOYAH - UNIT 2 2-7 E2-32

TABLE 2.2-1 (Continued) REACTOR TRIP SYSTEM INSTRUMENTATION TRIP SETPOINTS FUNCTIONAL UNIT TRIP SETPOINT _LE

19. Intermediate Range Neutron

-51 x 4% of RATED 2 6 x 4e% of RATED Flux, P-6, Enable Block THERMA"OWER THERMAL POWER Source Range Reactor Trip

20. Power Range Neutron Flux 0% of RATED THERMAL

< 12.4% of RATED THERM? (not P-10) Input to Low Powe POWER POWER Reactor Trips Block P-7

21. Turbine Impulse Chamber 0% Turbine Impulse Pressure

< 12.4% Turbine Impulse Pressure -(P-13) Input to Lo Equivalent Pressure Equivalent Power Reactor Trips Block P-7

22. Power Range Neutron Flux -

_5% of RATED THERMAL < 37.4% of RATED THERM? (P-8) Low Reactor Coolant OWER POWER Loop Flow, and Reactor Trip

23. Power Range Neutron Flux -

0 0% of RATED THERMAL 27.6% of RATED THERMAL (P-10) - Enable block of POWER POWER Source, Intermediate, and Power Range (low setpoint) Reactor Trips

24. Reactor Trip P-4 Not Applicable Not Applicable

25. Power Range Neutron Flux -

_0% of RATED THERMAL < 52.4% of RATED THERM? (P-9) Blocks Reactor Trip for OWER POWER Turbine - Trip Below 50% Rated Power AL L AL-October 31, 1990 Amendment Nos. 21, 129,132 SEQUOYAH - UNIT 2 2-8 E2-33

TABLE 2.2-1 (Continued) REACTOR TRIP SYSTEM INSTRUMENTATION TRIP SETPOINTS NOTATION NOTE 1: Overtemperature AT ( + rS) < ATo {Ki - K2 (71+ adS) [T - T'] + K3 (P - P) - fi (Al)} Where: I + T4S I + r5S = Lead-lag compensator on measured AT ATo Ki K2 1 + T'S I + A2S Time constants utilized in the lead-lag controller for AT, Z4 2 5 secs, Th

• 3 sec.

= Indicated AT at RATED THERMAL POWER 1.15 2 0.011 = The function generated by the lead-lag controller for Tan dynamic compensation Time constants utilized in the lead-lag controller for T8,,, Z 233 secs., T2 ' 4 secs. = Average temperature OF 578.22I°t RATED THERMAL POWER) = 0.00055 = Pressurizer pressure, psig = 2235 psig (Nominal RCS operating pressure) T Tp Pt September 15, 1995 Amendment No. 21,104, 132, 201 SEQUOYAH - UNIT 2 2-9 E2-34

TABLE 2.2-1 (Continued) REACTOR TRIP SYSTEM INSTRUMENTATION TRIP SETPOINTS NOTATION (Continued) NOTE 1: (Continued) S = Laplace transform operator (secl ) and f1 (Al) is a function of the indicated difference between top and bottom detectors of the power-range nuclear ion chambers; with gains to be selected based on measured instrument response during plant startup tests such that: (i) for qt - q, between QTNL* and QTPL* f, (Al) = 0 (where qt and qb are percent RATED THERMAL POWER in the top and bottom halves of the core respectively, and qt + qb is total THERMAL POWER in percent of RATED THERMAL POWER (ii) f nm a for each percent that the magnitude of (qt - qb) exceeds QTNL, the4T t point shall be automatically reduced by QTNS of its value at RATED ERMAL POWER. inominal for each percent that the magnitude of (qt - qb) exceeds QTPL, the tset-point shall be automatically reduced by QTPS of its value at RATED THERMAL POWER. NOTE 2: Op + 4S.) ° AT {K 4 K5 ( 1 T3S) -K 6 (T-T") -f2 (Al)} Where: 1 +T4S I + rS = as defined in Note 1 QTNL, QTPL, QTNS, and QTPS are specified in the COLR per Specification 6.9.1.14. April 21, 1997 Amendment No. 21, 132, 214 SEQUOYAH - UNIT 2 2-10 E2-35

TABLE 2.2-1 (Continued) REACTOR TRIP SYSTEM INSTRUMENTATION TRIP SETPOINTS NOTATION (Continued) NOTE 2: (Continued) r4 r-5 as defined in Note 1 4'5 ATO = as defined in Note 1 K4 1.087 K5 2 0.02/°F for increasing average temperature and 0 for decreasing average temperature -t3S = The function generated by the rate-lag controller for T8., 1 + n S dynamic compensation T Time constant utilized in the rate-lag controller for Tavg, T; 2 10 secs. K6 0.0011 for T >T" and K 2 0 for T < T" T = as defined in Note 1 T = Indicated Ta,, at RATED THERMAL POWER (Calibration temperature for AT instrumentation, < 578.20F) S = as defined in Note I and f2(AI) is a function of the indicated difference between top and bottom detectors of the power-range nuclear ion chambers; with gains to be selected based on measured instrument response during plant startup tests such that: (i) for qt - qb between QPNL* and QPPL* f2(AI) = 0 (where qt and qt are percent RATED THERMAL POWER in the top and bottom halves of the core respectively, and qt + qb is total THERMAL POWER in percent of RATED THERMAL POWER). (ii) n a for each percent that the magnitude of (qt - qb) exceeds QPNL setnt shall be automatically reduced by QPNS* of its value at RATED THERMAL POWER. (iii) nomia for each percent that the magnitude of (qt - qb) exceeds QPPLh tpp shall be automatically reduced by QPPS* of its value at RATEIHERMAL POWER.

• QPNL, QPPL, QPNS, and QPPS are specified in the COLR per Specification 6.9.1.14.

April 21, 1997 SEQUOYAH - UNIT 2 2-11 Amendment No. 21, 104, 132, 201, 214 E2-36

TABLE 2.2-1 (Continued) REACTOR TRIP SYSTEM INSTRUMENTATION TRIP SETPOINTS NOTATION (Continued) nominalJJ Jse NOTE 3: The channel's maximum trip setpoint shall not exceed its computed trip p0! by more than 1.9 percent AT span. nominal J NOTE 4: The channel's maximum trip setpoint shall not exceed it computed trip setpoin by more than 1.7 percent AT span. NOTE 5: Trip Time Delay - Steam Generator Water Level-Low-Low Ts = {(-0.00583)(P)3 + (0.735)(p) 2 (33.560)(P) + 649.5}{0.99} secs. Tm = ((-0.00532)(P) 3 + (0.678)(P) 2 - (31.340)(P) + 589.5}{0.99} secs. Where: P = RCS Loop AT Equivalent to Power (% RTP), P

• 50% RTP Ts=

Time delay for Steam Generator Water Level-Low-Low Reactor Trip, one Steam Generator affected (secs). Tm = Time delay for Steam Generator Water Level-Low-Low Reactor Trip, two or more Steam Generators affected (secs). SEQUOYAH - UNIT 2 October 4, 1995 Amendment No. 132, 203 2-12 E2-37

SAFETY LIMITS BASES 2.1.1 REACTOR CORE (Continued) These limiting heat flux conditions are higher than those calculated for the range of all control rods fully withdrawn to the maximum allowable control rod insertion assuming the axial power imbalance is within the limits of the fj(delta 1) function of the Overtemperature Delta T trip. When the axial power imbalance is not within the tolerance, the axial power imbalance effect on the Overtemperature delta T trips will reduce the setpoints to provide protection consistent with core safety limits. 2.1.2 REACTOR COOLANT SYSTEM PRESSURE The restriction of this Safety Limit protects the integrity of the Reactor Coolant System from overpressurization and thereby prevents the release of radionuclides contained in the reactor coolant from reaching the containment atmosphere. The reactor pressure vessel and pressurizer are designed to Section Ill of the ASME Code for Nuclear Power Plant which permits a maximum transient pressure of 110% (2735 psig) of design pressure. The Reactor Coolant System piping, valves and fittings, are designed to ANSI B 31.1 1967 Edition, which permits a maximum transient pressure of 120% (2985 psig) of component design pressure. The Safety Limit of 2735 psig is therefore consistent with the design criteria and associated code requirements. The entire Reactor Coolant System is hydrotested at 3107 psig, 125% of design pressure, to demonstrate integrity prior to initial operation. 2.2.1 REACTOR TRIP SYSTEM INSTRUMENTATION SETPOINTS 4-o fiin a I} Th Reactor Trip Setpoin Limits specifiedi e are the values at which the r Nominal Reactor Trips are set for each functional unit.lTeTip Setpoints ave been selected to ensure that the reactor core and reactor coolant system are preventfro ding their safety limits during normal operation and design basis anticipated operational occurrences and to assist the Engineered Safety Features Actuation System i h consequences of accidents. Operation with a trip set less conservative tha its Trip Setpoint but withiits specified Allowable lo Nominal 4 Value is acceptable on thea differen rip Set oi and the Allowable Value is equal to or less thane Sllowanc assumed for each trip in the safety analyses. Add Insert I Add Insert 2 March 30, 1992 SEQUOYAH - UNIT 2 B 2-2 Amendment Nos. 130, 146 E2-38

INSTRUMENTATION 3/4.3.2 ENGINEERED SAFETY FEATURE ACTUATION SYSTEM INSTRUMENTATION LIMITING CONDITION FOR OPERATION 3.3.2 The Engineered Safety Feature Actuation System (ESFAS) instrumentation channels and in 9 3.3-3 shall be OPERABLE with their trip setpoints set consistent with the values shown in he Trip Setpointolumn of Table 3.3-4. APPLlCABl~I': As shown in Table 3.3-3. ACTION:

a.

With an ESFAS instrumentation channel or interlock trip setpoint less conservative than the value shown in the Allowable Values column of Table 3.3-4, declare the channel inoperable and apply the applicable ACTION requirement of Table 3.3-3 ne restored to OPERABLE status with the trip setpoint adjusted consistent wi the Trip Setpoin value. Atf Nominal

b.

With an ESFAS instrumentation channel or interlock inoperable, ta elATION shown in Table 3.3-3. SURVEILLANCE REQUIREMENTS 4.3.2.1.1 Each ESFAS instrumentation channel and interlock shall be demonstrated OPERABLE by the performance of the CHANNEL CHECK, CHANNEL CALIBRATION and CHANNEL FUNCTIONAL TEST operations for the MODES and at the frequencies shown in Table 4.3-2. 4.3.2.1.2 The logic for the interlocks shall be demonstrated OPERABLE during the automatic actuation logic test. The total interlock function shall be demonstrated OPERABLE at least once per 18 months during CHANNEL CALIBRATION testing of each channel affected by interlock operation. 4.3.2.1.3 The ENGINEERED SAFETY FEATURES RESPONSE TIME of each ESFAS function shall be verified to be within the limit at least once per 18 months. Each verification shall include at least one train such that both trains are verified at least once per 36 months and one channel per function such that all channels are verified at least once per N times 18 months where N is the total number of redundant channels in a specific ESFAS function as shown in the "Total No. of Channels" Column of Table 3.3-3. February 29, 2000 Amendment No. 182, 242 SEQUOYAH - UNIT 2 3/4 3-14 E2-39

TABLE 3.3-3 (Continued) ENGINEERED SAFETY FEATURE ACTUATION SYSTEM INSTRUMENTATION TOTAL NO. OF CHANNELS CHANNELS TO TRIP MINIMUM CHANNELS OPERABLE APPLICABLE MODES FUNCTIONAL UNIT ACTION

e. Loss of Power Start

1. Voltage Sensors

2. Load Shed Timer

f.

Trip of Main Feedwater Pumps Start Motor-Driven Pumps and Turbine Driven Pump 3/shutdown board 2/shutdown board 1/pump 2/shutdown 3/shutdown board** oard** JX1 1/shutdown /shutdown board 1, 2, 3 35 1, 2, 3 35 1/pump 1/pump 1, 2 20*

g. Auxiliary Feedwater Suction Pressure-Low

h. Auxiliary Feedwater Suction Transfer Time Delays

1. Motor-Driven Pump

2. Turbine-Driven Pump 3/pump 2/pump 3/pump 1, 2, 3 21*

1/pump 2/pump 1/pump 1/pump 1/pump 2/pump 1, 2, 3 1, 2,3 21* 21*

• • Unit 2 Shutdown Boards Only August 22, 1995 Amendment No. 29,116,174,180, 197 SEQUOYAH - UNIT 2 3/4 3-20 E2-40

TABLE 3.3-3 (Continued) ENGINEERED SAFETY FEATURE ACTUATION SYSTEM INSTRUMENTATION TOTAL NO. OF CHANNELS CHANNELS TO TRIP MINIMUM CHANNELS OPERABLE APPLICABLE MODES FUNCTIONAL UNIT ACTION

7.

LOSS OF POWER

a.

6.9 kv Shutdown Board -Loss of Voltage

1.

Voltage Sensors

2. Diesel Generator Start and Load Shed Timer 3/shutdown board 21shutdown board 2/shutdown board 1/shutdown board 3/shutdown 5wa##

6#4#~ 1 2

1. 3 4

5II,61A 34 34

b.

6.9 kv Shutdown Board Degraded Voltage

1. Voltage Sensors 3/shutdown board 2/shutdown board 3/shutdown board 5kh,3 69#

34

2. Diesel Generator Start and Load Shed Timer

3. SI/Degraded Voltage Logic Enable Timer 2/shutdown board 2/shutdown board 1/shutdown board 1/shutdown board 1, 2,3, 4 34 34 SEQUOYAH - UNIT 2 3/4 3-21 August 22, 1995 Amendment No. 18, 132,150, 174, 180, 197 E2-41

TABLE 3.3-3 (Continued) ACTION 21 - ACTION 22-With less than the Minimum Number of Channels OPERABLE, declare the associated auxiliary feedwater pump inoperable, and comply with the ACTION requirements of Specification 3.7.1.2. With less than the Minimum Number of Channels OPERABLE, declare the interlock inoperable and verify that all affected channels of the functions listed below are OPERABLE or apply the appropriate ACTION statement(s) for those functions. Functions to be evaluated are:

a.

Safety Injection Pressurizer Pressure Steam Line Pressure Negative Steam Line Pressure Rate

b.

Deleted

c.

Turbine Trip Steam Generator Level High-High Feedwater Isolation Steam Generator Level High-High ACTION 23 - ACTION 24 - ACTION 25-With the number of OPERABLE channels one less than the Total Number of Channels, be in at least HOT STANDBY within 6 hours and in at least HOT SHUTDOWN within the following 6 hours; however, one channel may be bypassed for up to 2 hours for surveillance testing per Specification 4.3.2.1.1. With the number of OPERABLE channels one less than the Total Number of Channels, restore the inoperable channel to OPERABLE status within 48 hours or be in at least HOT STANDBY within 6 hours and in at least HOT SHUTDOWN within the following 6 hours. With the number of OPERABLE channels one less than the Total Number of Channels, restore the inoperable channel to OPERABLE status within 48 hours or declare the associated valve inoperable and take the ACTION required by Specification 3.7.1.5. ACTION 34 -

a. Whannels one less than the Total Number of f

U forvoltage sensors restore the inoperable hannel to OPERABLE status within 6 hours or enter ion(s) r Operation and Action(s) for the associated diesel generator set made inoperable by the channel. le than the Total Number of Channels by r1 fr vltge sensors or tiers more than one, restore all but one channel to ERABLE status within 1 hour or enter apicable Limiting C on and Action(s) for the associated diesel generator set made inoperable by the channels. SEQUOYAH - UNIT 2 3/4 3-23 August 22, 1995 Amendment No. 55, 116, 132, 150, 174, 180, 197 E2-42

TABLE 3.3-3 (Continued) ACTION 35-

a.

nthe urn L cannels one less than the Total Number of J' for voltage sensors) 4 Ch~qid&estore the inoperab~fchannel to OPERABLE status within 6 hours or enter applcation(s) For Operation and Action(s) for the associated auxiliary feedwater pump made inoperable by the channel.

b.

With the number of OPE E chf / JUforvoltge ensrs or timers Channels by more than one, restore all but one channel to OPERABLE statu within 1 hour or enter applicab ei ) the associated auxiliary feedwater pump made inoperable by the channels. ACTION 36 - With the number of OPERABLE channels one less than the Total Number of Channels, STARTUP and/or POWER OPERATION may proceed provided the following conditions are satisfied:

a.

The inoperable channel is placed in the tripped condition within 6 hours.

b.

For the affected protection set, the Trip Time Delay for one affected steam generator (Ts) is adjusted to match the Trip Time Delay for multiple affected steam generators (TM) within 4 hours.

c.

The Minimum Channels OPERABLE requirement is met; however, the inoperable channel may be bypassed for up to 4 hours for surveillance testing of other channels per Specification 4.3.2.1.1. ACTION 37 - With the number of OPERABLE channels one less than the Total Number of Channels, STARTUP and/or POWER OPERATION may proceed provided that within 6 hours, for the affected protection set, the Trip Time Delays (Ts and TM) threshold power level for zero seconds time delay is adjusted to 0% RTP. ACTION 38 - With the number of OPERABLE channels one less than the Total Number of Channels, STARTUP and/or POWER OPERATION may proceed provided that within 6 hours, for the affected protection set, the Steam Generator Water Level - Low-Low (EAM) channels trip setpoint is adjusted to the same value as Steam Generator Water Level - Low-Low (Adverse). August 22, 1995 Amendment No. 132,150,174,180,197 SEQUOYAH - UNIT 2 3/4 3-23a E2-43

TABLE 3.3-4 ENGINEERED SAFETY FEATURE ACTUATION SYSTEM INSTRUMENTATION TRIP SETPOINTS )JNOMINAL FUNCTIONAL UNIT TRIP SETPOINT ALLOWABLE VALUES ^ Af-f Oki ,,-1,fO,- -rf-I*n f 1. SAFE I I INJt-Cl I N, I UKBINE I RIP AND FEEDWATER ISOLATION

a. Manual Initiation

b. Automatic Actuation Logic

c. Containment Pressure-High

d. Pressurizer Pressure-Low

e. Deleted

f. Steam Line Pressure-Low Not Applicable Not Applicable 1.54 psig I 1870 psig 00 psig steam line pressure (Note 1)

Not Applicable Not Applicable <1.6 psig 21864.8 psig Ž592.2 psig steam line pressure (Note 1) October 31, 1990 Amendment Nos. 55,132 SEQUOYAH - UNIT 2 3/4 3-24 E2-44

TABLE 3.3-4 (Continued) ENGINEERED SAFETY FEATURE ACTUATION SYSTEM INSTRUMENTATION TRIP SETPOINTS (UNOMINAL FUNCTIONAL UNIT TRIP SETPOII

2.

CONTAINMENT SPRAY

a.

Manual Initiation Not Applicable

b. Automatic Actuation Logic Not Applicable

c. Containment Pressure-High-High

&2.81 psig

3. CONTAINMENT ISOLATION

a. Phase "A" Isolation

1. Manual Not Applicable

2. From Safety Injection Not Applicable Automatic Actuation logic

b.

Phase "B" Isolation

1. Manual Not Applicable

2. Automatic Actuation Logic Not Applicable

3.

Containment Pressure-High-High (j .81 psig

c.

Containment Ventilation Isolation

1. Manual Not Applicable

2. Automatic Isolation Logic Not Applicable JT ALLOWABLE VALUES Not Applicable Not Applicable S2.9 psig Not Applicable Not Applicable Not Applicable Not Applicable S2.9 psig Not Applicable Not Applicable October 31, 1990 3/4 3-25 Amendment No. 132 SEQUOYAH - UNIT 2 E2-45

TABLE 3.3-4 (Continued) ENGINEERED SAFETY FEATURE ACTUATION SYSTEM INSTRUMENTATION TRIP SETPOINTS UNOMINAL FUNCTIONAL UNIT

3. Containment Purge Air Exhaust Monitor Radioactivity - High

4.

STEAM LINE ISOLATION

a. Manual

b. Automatic Actuation Logic

c. Containment Pressure-High-High

d. Steam Une Pressure-Low

e. Negative Steam Line Pressure Rate-High

5. TURBINE TRIP AND FEEDWATER ISOLATION

a. Steam Generator Water level -

High-High

b. Automatic Actuation Logic SEQUOYAH - UNIT 2 TRIP SETPOINT ALLOWABLE VALUES

• 8.5x 10 3 ptCi/cc

<8.5x 10 3pCi/cc Not Applicable Not Applicable Not Applicable Not Applicable <2.9 psig line 2592.2 psig steam line pressure (Note 1)

2)

<107.8 psi (Note 2) 100.0 psi (Note 481% of narrow range <81.7% of narrow instrument span each range instrument span steam generator each steam generator N.A. N.A. June 25, 1993 6 Amendment Nos. 55, 132, 158 3/4 3-2( E2-46

TABLE 3.3-4 (Continued) ENGINEERED SAFETY FEATURE ACTUATION SYSTEM INSTRUMENTATION TRIP SETPOINTS JJNOMINAL FUNCTIONAL UNIT TRIP SETPOINT ALLOWABLE VALUES

6. AUXILIARY FEEDWATER

a.

Manual Not Applicable Not Applicable Not Applicable

b. Automatic Actuation Logic Not Applicable

c.

Main Steam Generator Water Level-Low-Low I. RCS Loop AT Equivalent to Power *50% RTP RCS Loop AT variable inpB Rt iggpRCnable 50% RTP P Jnnominali iJnputS trip setpointI +27 Coincident with Steam Generator Water Level-Low-Low (Adverse) and Containment Pressure-EAM or Steam Generator Water Level-Low-Low (EAM) with A time delay (Ts) if one Steam Generator is affected or A time delay (TM) if two or more Steam Generators are affected Ž-.15.0% of narrow range instrument span .5 psig 10.7% of narrow range instrument span i Ts (Note 5, Table 2.2-1) - M (Note 5, Table 2.2-1) 214.4% of narrow range instrument span

• 0.6 psig 210.1% of narrow instrument span
• (1.01) Ts (Note 5, Table 2.2-1)
• (1.01) TM (Note 5, Table 2.2-1)

October 31, 1990 Amendment Nos. 18, 84,132 SEQUOYAH - UNIT 2 3/4 3-27 E2-47

TABLE 3.3-4 (Continued) ENGINEERED SAFETY FEATURE ACTUATION SYSTEM INSTRUMENTATION TRIP SETPOINTS tLNOMINAL FUNCTIONAL UNIT TRIP SETPOINT ALLOWABLE VALUES ii. RCS Loop AT Equivalent Power> 50% RTP Coincident with Steam 5.0% of narrow range 214.4% of narrow range Generator Water Level-instrument span instrument span Low-Low (Adverse) and Containment Pressure .5 psig

• 0.6 psig (EAM) or Steam Generator Water 10.7% of narrow range 210.1 % of narrow range Level-Low-Low (EAM) instrument span instrument span

d. S.I.

See 1 above (all Si Setpoints)

e. Loss of Power Start

1. Voltage Sensors

2.

Load Shed Timer 5520 volts 1.25 seconds 2 5331 volts 21.O0 second and S1.5O 1.25 +/-0.25 seconds N.A.

f. Trip of Main Feedwater Pumps N.A.

g. Auxiliary Feedwater Suction Pressure-Low

h. Auxiliary Feedwater Suction Transfer Time Delays SEQUOYAH - UNIT 2 3.21 psig (motor driven pump) 2 2.44 psig (motor driven pump) 13.9 psig (turbine driven pump) 2 12 psig (turbine driven pump) 4 seconds (motor driven pump) 4.4 seconds 23.6 seconds 4 4 4R

_ ~ -, (m otor X driven pump) soconde \\ 5.5 seconds (turbine driven

• T6.05 seconds pump)

Ž 4.95 seconds 5.5 seconds +0.55 eeGeOdG(turbine driven Spump) 3/4 3-27a March 1, 1996 Amendment Nos. 18, 84, 116, 132, 174, 175,180, 197, 209 E2-48

TABLE 3.3-4 (Continued) ENGINEERED SAFETY FEATURE ACTUATION SYSTEM INSTRUMENTATION TRIP SETPOINTS INOMINAL FUNCTIONAL UNIT TRIP SETPOINT ALLOWABLE VALUES

7. LOSS OF POWER

a. 6.9 kv Shutdown Board Undervoltage Loss of Voltage

1. Voltage Sensors

2. Diesel Generator Start and Load Shed Timer

b. 6.9 kv Shutdown Board-Degraded Voltage

1. Voltage Sensors

2. Diesel Generator Start and Load Shed Timer

3. SI/Degraded Voltage Logic Enable Timer

8. ENGINEERED SAFETY FEATURE ACTUATION SYSTEM INTERLOCKS

a. Pressurizer Pressure

1. Not P-11, Automatic Unblock of Safety Injection on Increasing Pressure

2. P-11, Enable Manual Block of Safety Injection on Decreasing Pressure

( 50volt ! 2 5331 volts ~~ > 1.00 seconds and S 1.50 1.25 seconds 4.25 +/- 0.25 seconds ) 6403.5 volts (dropout) 6456 volts <_ 6595.5 volts (reset) -300 seconds < 370 seconds Ž > 7.5 seconds and 5 11.5 9.5 seconds Q.5 + 2.0 seconds FFS1970 psig 962 psig

• 1975.2 psig 21956.8 psig SEQUOYAH - UNIT 2 314 3-27b March 1, 1996 Amendment Nos. 18, 25,116, 132,174, 180, 197, 209 E2-49

TABLE 3.3-4 (Continued) ENGINEERED SAFETY FEATURE ACTUATION SYS§EM INSTRUMENTATION TRIP SETPOINTS )VNOMINAL FUNCTIONAL UNIT TRIP SETPOINT ALLOWABLE VALUES

8. ENGINEERED SAFETY FEATURE ACTUATION SYSTEM INTERLOCKS (Continued)

b. Deleted

c.

Deleted

d. Steam Generator Level Turbine Trip, Feedwater Isolation P-14

9. AUTOMATIC SWITCHOVER TO CONTAINMENT SUMP

a. RWST Level - Low COINCIDENT WITH Containment Sump Level - High AND Safety Injection

b. Automatic Actuation Logic (See 5. above) 130" from tank base 30" above elev. 680' lS13.1 from tank base

\\, z1 127.29" 130" + t.71 from tank base (See 1 above for all Safety Injection Setpoints/Allowable Valves) N.A. N.A. Note 1: Time constants utilized in the lead-lag controller for Steam Pressure-Low are Ai Ž 50 seconds and t 2 < 5 seconds. Note 2: Time constant utilized in the rate-lag controller for Negative Steam Line Pressure Rate-High is T, 50 seconds. October 31, 1990 Amendment Nos. 5, 55,132 SEQUOYAH - UNIT 2 3/4 3-28 E2-50

TABLE 3.3-6 RADIATION MONITORING INSTRUMENTATION MINIMUM CHANNELS OPERABLE APPLICABLE MODES ALARM/TRIP SETPOINT MEASUREMENT RANGE INSTRUMENT ACTION

1. AREA MONITOR

a.

Fuel Storage Pool Area 1 10-' _ 104 mR/hr 26

2. PROCESS MONITORS

a. Containment Purge Air 1

1, 2, 3,4 & 6

• 8.5 x 10-3 pci/cc 10 - 107 cpm 28

b. Containment

i. Gaseous Activity RCS Leakage Detection 1

1,2, 3 &4 N/A 10 -I0 cpm 27 ii. Particulate Activity RCS Leakage Detection 1 1, 2,3 & 4 N/A 10- 107 cpm 27

c. Control Room Isolation 2

ALL MODES and during movement of irradiated fuel assemblies

• 400 cpm**

10 - I W cpm 29 With fuel in the storage pool or building

• • Equivalent to 1.0 x 10 pCi/cc.

May 31, 2000 Amendment Nos. 52, 102, 158, 247 SEQUOYAH - UNIT 2 3/4 3-41 E2-51

3/4.3 INSTRUMENTATION BASES 3/4.3.1 and 3/4.3.2 REACTOR TRIP AND ENGINEERED SAFETY FEATURE ACTUATION SYSTEM INSTRUMENTATION The OPERABILITY of the Reactor Trip and Engineered Safety Features Actuation Systems instrumentation and interlocks ensure that 1) the associated action and/or reacto4twp.. nominal trip be initiated when the parameter monitored by each channel or combination the p cfhes itssetpint,

2) the specified coincidence logic is maintained, 3) sufficient redundancy is maintained to channel to be out of service for testing or maintenance, and 4) sufficient system functional capability is available from diverse parameters.

The OPERABILITY of these systems is required to provide the overall reliability, redundancy and diversity assumed available in the facility design for the protection and mitigation of accident and transient conditions. The integrated operation of each of these systems is consistent with the assumptions used in the accident analyses. The surveillance requirements specified for these systems ensure that the overall system functional capability is maintained comparable to the original design standards. The periodic surveillance tests performed at the minimum frequencies are sufficient to demonstrate this capability. The Engineered Safety Feature Actuation System interloctions indicated below on increasing the required parameter, consistent listed in able 3.3-4: >1 nnominal trip P-11 Defeats the manual block of safety injection actuation on low pressurizer pressure. P-14 Trip of all feedwater pumps, turbine trip, closure of feedwater isolation valves and inhibits feedwater control valve modulation. On decreasing the required parameter the opposite function is performed at reset setpoints. The surveillance for the comparison of the incore to the excore Axial Flux Difference is required only when reactor power is > 15 percent. The 96 hour delay in the first performance of the surveillance after reaching 15 percent reactor thermal power (RTP), following a refueling outage, is to achieve a higher power level and approach Xenon stability. The surveillance is typically performed when RTP is > 30 percent to ensure the results of the evaluation are more accurate and the adjustments more reliable. The frequency of 31 EFPD is to allow slow changes in neutron flux to be better detected during the fuel cycle. May 30, 1995 SEQUOYAH - UNIT 2 B 3/4 3-1 Amendment No. 132,190 E2-52}}