ML18057A763

Application for Amend to License DPR-20,changing Tech Specs to Clarify Operating Requirements for Instrumentation & Control Sys & Instrument Accuracy Re wide-range Channel to Resolve Inconsistencies in LER 91-001 Dtd 910102

ML18057A763
Person / Time
Site:	Palisades
Issue date:	02/27/1991
From:	SLADE G B CONSUMERS ENERGY CO. (FORMERLY CONSUMERS POWER CO.)
To:	NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
Shared Package
ML18057A764	List: ML18057A763 ML18057A765
References
NUDOCS 9103070001
Download: ML18057A763 (7)

Text

. *' ... consumers Power POW ERi Nii MICHlliAN'S PRDliRESS Palisades Nuclear Plant: 27780 Blue Star Memorial Highway, Covert, Ml 49043 February 27, 1991 Nuclear Regulatory Commission Document Control Desk Washington, DC 20555 B Slade General Manager DOCKET

-LICENSE DPR-20 -PALISADES PLANT -TECHNICAL SPECIFICATIONS CHANGE REQUEST -INSTRUMENT AND CONTROL SYSTEMS Enclosed is a proposed change to the Palisades Technical to clarify the operating requirements for the Instrument and.Control systems. In addition, this change incorporates instrument inaccuracy into the permissible by°pass conditions for the wide range channel and loss of load reactor trips to resolve inconsistencies described in LER 91-001, dated January 2, 1991. Attachment 1 contains the proposed Technical Specifications pages; Attachment 2 contains existing Technical Specifications pages marked *up with the c.hanges.

Because of the desirabiliti of using these proposed changes if Palfsades enters a forced shutdown after startup from the current refueling outage, we ask this change request be processed as quickly as possible.

The amendment should be made effecttve upon date of issuance.

Gerald B Slade General Manager CC Administrator, Region III, USNRC Palisades NRC Inspector A CMS' ENERGY COMPANY

' . .* .. CONSUMERS POWER COMPANY Docket 50-255 Request for Change to the Technical Specifications License DPR-20 1 For the reasons hereinafter set forth, it is requested that the Technical Specifications contained in the Facility Operating License DPR-20, Docket 50-255, issued to Consumers Power Company on February 21, 1991, for the Palisades Plant be changed as described in Section I below: I. Changes A. In the Applicability portion of Section 3.17, delete "Applies to plant instrumentation systems." and insert "The instrumentation and control systems shall be operable under the following conditions:

Table 3.17.1 -When the PCS has less than Refueling Boron Concentration and more than one control rod is capable of being withdrawn except as allowed by the permissible bypass conditions.

Table 3.17.2 -When the PCS temperature is >325°F except as allowed by the permissible bypass conditions.

Table 3.17.3 -When the PCS is above Cold Shutdown except as allowed by the permissible bypass conditions.

Table 3.17.4 -At all times except as allowed by the permissible bypass conditions." B. Delete Section 3.17.1. C. After the first paragraph of the Basis in Section 3.17 insert the information marked "B" in marked up pages, Attachment

2. D. On Table 3.17.1, delete footnotes (g) and (h) and the references to them in the Functional Unit column of Items 1-10. E. On Table 3.17.1, Item 3, in the Permissible Bypass Conditions column, delete "15%" and insert "13%". F. On Table 3.17.1, Item 7, in the Permissible Bypass Conditions column, delete "None" and add "Below 173 Rated Powerca> " F.l On Table 3.17.2, items lb and 2b ,and Table 3.17.3, item la, in the Permissible Bypass Conditions delete "During Leak Test" and add "None." G. On Table 3.17.4, Item 1, in the Permissible Bypass Conditions column, add a new condition "Not required below 325°F." H. On Table 3.17.4, Item 2, in the Permissible Bypass Conditions column delete "None" and add "Not required at our below Hot Shutdown."

2 I. On Table 3.17.4, Item 4, in the Permissible Bypass Conditions column delete "None" and add "Not required below 325°F." J. On Table 3.17.4, Item 5, in the Permissible Bypass Conditions column delete "NA" and add "Not required at or below Hot Shutdown." K. On Table 3.17.4, Item 7, in the Permissible Bypass Conditions column, add after " ... Rated Power", "or with no fuel in the reactor." L. On Table 3.17.4, Item 10, in the Functional Unit column after "Relief Valves" add "Position Indication", and in the Permissible Bypass Conditions column after "Not required" add "in cold shutdown or." II. Discussion This change to Section 3.17 is proposed to clarify applicability requirements and to incorporate instrument accuracy allowance to the permissible bypass conditions for both the loss of load trip and the wide range channel input to the rate of change trip. Progressive changes to Table 3.17.1 adding various applicability requirements have made its interpretation unwieldy to the extent that letters of interpretation are necessary for its practical use. In addition, it was recently realized that no allowance had been made for instrument inaccuracy of the single bistable controlling the automatic bypass removal of the loss of load trip and the wide range channels (LER 91-001, dated January 2, 1991). Change A defines the Applicability of all four tables which. comprise Section 3.17. Table 3.17.1, Instrumentation Operating Requirements for Reactor Protective System (RPS), instrumentation clearly should not be applicable when the PCS is at Refueling Boron Concentration because 5% shutdown margin is available even if all rods are removed from the core; and additionally, Table 3.17.1 should not be applicable unless there is more than one control rod capable of removal because the safety analyses the Shutdown Margin definition use the assumption that the highest worth control rod will fail to trip. Thus, when only one or none of the control rods are capable of withdrawal or when the PCS is at refueling boron concentration, a reactor trip is not needed and the RPS is not required.

These clarifications more closely align the RPS instrumentation to the Standard Technical Specifications mode applicability requirements and allow for testing of control rod drives. Table 3.17.2, Instrumentation Operating Requirements for Engineered Safety Feature Systems, instrumentation is not required when the PCS temperature is less than 325°F because below that temperature the PCS can be cooled by the Shutdown Cooling System. Consistent with other Technical Specifications and plant administrative operability requirements, there is no need for either safety injection or containment spray below 325°F. Table 3.17.3, Instrument Operating Conditions for Isolation Functions, instrumentation is not needed until after the PCS is above cold shutdown because in cold shutdown there is no need for containment isolation or main steam line-isolation.

This is consistent with other Specifications requirements.

3 Table 3.11.4, Instrumentation Operating Requirements for Other Safety Feature Functions, instrumentation applicability is defined as at all times however, Permissible Bypass Conditions exist or have been proposed for all items in the table and are consistent with the associated system operating conditions.

Change B deletes an unnecessary statement that has been replaced by the proposed Applicability.

Change C adds basis statements for the RPS for clarification.

Change D deletes Footnotes (g) and (h) from 3.17.1. Footnote (g) is overly restrictive as it would not, for instance, allow testing with . only one control rod capable of being withdrawn.

Footnote (h), as described in LER 91-001, does not contain instrument accuracy tolerance.

Information contained in these footnotes is now enveloped by the Applicability of Section 3.17 and the Permissible Bypass Conditions column of Table 3.17.1. Changes E and F which permits bypass of the Wide Range Channels when Rated Power is above 13% and bypass of the Loss of Load trip when the Rated Power is below 17%, incorporate instrument inaccuracy of the bistable and do not affect safety because no credit is taken for the anticipatory Loss of Load trip and the Wide Range Channel, Rate of Power Change, reactor trip in the safety analyses.

The automatic bypass removal at <15% Rated Power for the Loss of Load Trip has been replaced by a <17% Rated Power requirement that includes instrument uncertainty (Change F). The same is true for the automatic bypass removal above 15% Rated Power for the Wide Range Channels which has been replaced by a greater than 13% Rated Power automatic bypass (Change E). Both automatic bypass removals are controlled by a single bistable unit which is nominally set at 15% Rated Power. Change F.l deletes Permissible Bypass Conditions to not require High Containment Pressure actuation of safety injection, containment spray and containment isolation when conducting a containment leak test. With the proposed applicability for Tables 3.17.2 and 3.17.3, presented in change A above, the instrumentation will not be required operable during a containment leak test and therefore the Permissible Bypass Conditions have been changed deleted. Change G requires the safety injection and refueling water tank level switches, which initiate a post accident containment recirculation actuation signal, to be operable when the primary coolant temperature is

• at or above 325°F. This is consistent with safety injection and containment spray applicability requirements.

Change H will require the AT -Power Comparator, which compares thermal power to nuclear power, to be operable prior to critical.

4 Change I requires the containment air cooler service water flow instruments-to be operable when the containment air coolers are required operable.

Change J will require the Control Rod Primary and Secondary Insertion monitors to be operable when above hot shutdown (ie hot standby and power ope_ration).

Out-of-Sequence monitoring is a function of the secondary rod insertion monitor. Control rod bank withdrawal is only used during hot standby and *power operation.

Therefore, when at hot shutdown and below, where only one rod is allowed to be withdrawn at any time, the control rod insertion monitors, the bank out-of-sequence monitoring are not required.

Change K adds an obvious bypass condition to the startup channels {Table 3.17.4, Item 7) since they are not required when there is no fuel in the reactor. -Change L clarifies the functional unit as the position indication for , the Power Operated Relief Valves (PORVs) and adds a bypass condition of while in cold shutdown when the acoustic monitor and temperature indication is not in an operable condition.

III. Analvsis of No Significant Hazards Consideration This change request clarifies the Applicability for Section 3.17, and changes Permissible Bypass Conditions in Table 3.17.1 for Wide Range Channels and Loss of Load reactor trips, removes the Permissible Bypass -Conditions in Tables 3.17.2 and 3.17.3, for High Containment Pressure instrumentation, and changes the Permissible Bypass Conditions, in Table 3.17.4, for the SIRWT Low-Level Switches, -Power Comparator, Air Cooler Service Water Flow Instruments, Primary and Secondary Rod Insertion and Out-of-Sequence Monitors, and Power Operated Relief Valves Position Indication.

The changes are consistent -with the plant safety analyses and system operability requirements for the affected instrumentation.

Therefore, Consumers Power Company finds that activities associated with this proposed Technical Specifications change involve no significant hazards; and accordingly, a no significant hazards determination per 10CFR50.92(c) is justified.

The following evaluation supports the finding that the proposed changes would not: 1. Involve a significant increase in the probability or consequences of an accident previously evaluated.

This change does not involve a significant increase in the probability or consequences of an accident previously evaluated because the only previously evaluated accidents of concern are an inadvertent return to criticality by withdrawal of a bank of control rods or dilution of the PCS boron concentration.

The consequences of an inadvertent rod bank withdrawal are analyzed in Section 14.2 of the FSAR and found to be acceptable assuming certain reactor trip functions are available as specified in this proposed technical specification change. An inadvertent dilution would be recognized by a signal from the Startup Range Channels.

This event is analyzed in the plant safety analyses.

Bypassing the RPS trips when at less than refueling boron concentration and when no more than one control

\. rod can be withdrawn or when the PCS is at refueling boron concentration presents no significant hazard because under these conditions an inadvertent criticality due to control rod bank withdrawal is not possible.

I 2. Create the possibility of a new or different kind of accident from any accident previously evaluated.

5 This change does not create the possibility of a new or different kind of accident from any accident previously evaluated because the proposed change only increases clarity of interpretation, incorporates instrument inaccuracy concerning two anticipatory reactor trips for which no credit is assumed in the safety analysis, and involves no significant changes to the method of operation nor the material condition of the plant. 3. Involve a significant reduction in the margin of safety. This change does not involve a significant reduction in the margin of safety because the margins of safety involved are (1), the 5%Ap margin when the PCS is at Refueling Boron concentration; and (2), the margin provided when PCS boron concentration is sufficient to provide Keff 0.98 with all control rods in the core and the highest worth control rod fully withdrawn (Shutdown Boron Concentration).

These margins are not diminished by the proposed changes.

IV. Conclusion The Palisades Plant Review Committee has reviewed this Technical Specifications Change Request arid has determined that this change does not involve an unreviewed safety question.

Further, the change involves no significant hazards consideration.

This change has been reviewed by the Nuclear Safety Services Department.

A copy of this Technical Specifications Change Request has been sent to the State of Michigan official designated to receive such Amendments to the Operating License. CONSUMERS POWER COMPANY To the best of my knowledge, information and belief, the contents of this Technical Specifications Change Request are truthful and complete. David P Hoffman, i esident Nuclear Operations Sworn and subscribed to before me this ]J_ day of Februray LeAnn Morse , Notary Public , __ ,_ -----;:.*

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