ML20245J451

Safety Evaluation Responding to Issues Re Tech Spec Upgrade & Plant Defueling.Stated Tech Spec Sections Should Be Upgraded

ML20245J451
Person / Time
Site:	Fort Saint Vrain
Issue date:	08/08/1989
From:	Heitner K Office of Nuclear Reactor Regulation
To:
Shared Package
ML20245J446	List: ML20245J442 ML20245J451
References
NUDOCS 8908180038
Download: ML20245J451 (6)

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UNITED STATES i

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3,GJ ! NUCLEAR REGULATORY COMMISSION w y,g s.~...+

WASH WGTON,0. C. 20$55 SAFETY EVALUATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION CONCERNING THE TECHNICAL SPECIFICATION UPGRADE PROGRAM FOR FORT ST. VRAIN NUCLEAR GENERATING STATION PUBLIC SERVICE COMPANY OF COLORADO DOCKET NO. 50-267

1.0 INTRODUCTION

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In letters dated May 11 and May 15, 1989, Public Service Company nf Colorado'(PSC) indicated two fundamental changes in its approach to the defueling of Fort St. Vrain (FSV) ano its conduct of operations during the defueling period. The first change is that PSC would ccr. duct the defueling of FSV under 10 CFR 50.59. The second is that PSC would not request

-part further Technical of the Specification Technical changes Specification Upgradespecifically(TSUP).for Program defueling, These or as viewpoints were presented by PSC.at a meeting with NRC managers on May 11, 1989. The staff has evaluated the TSUP issues, as presented in PSC's letters.

In ccnducting this review, the staff considered a number of other documents, including NRC Region IV's letter dated July 19, 1985, and your letters dateo July 10, 1985, January 20 and June 16, 1989. Our evaluation of these issues follows. The staff's review of the TSUP focused on implementation to assure plant safety through the defueling and shutdown phase.

PSC's comm.. ment to TSUP cates back to 1985. PSC's " good faith" efforts to work on TSUP were the basis for a number of significant actions by the staff in allowing PSC to operate FSV since 1985. The commitment to the TSUP is important to safety because the 1984 Assessment Report found that the FSV TS ...need substantial improvement to (a). correct deficiencies in content, (b) improve clarity and (c) correct errors." Although some improvement has occurred through other licensing actions, fundamental problems remain unresolved. By letter dated April 19, 1989, the staff transmitted to PSC a draft of the TSUP Technical Evaluation Report (TER).

The TER documents the specific improvements offered by the TSUP.

Reactivity Control l One of the most substantial and fundamental improvements to safety at FSV is the revised TS on Reactivity Control. By letter dated July 10, 1985 PSC committed to an Interim TS on Reactivity Control as a precondition for centinued operation of FSV. PSC committed to operate FSV in accordance with procedures based on the Interim TS until formal TS are approved and implemented. Since the review of PSC's proposals by the staff is essentially 8908180030 890008 i PDR ADOCK 05000267 s P PNU [

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complete, this is the time to finalize the TS for. reactivity control.

~Therefore,lthe staff. concludes that PSC should submit upgraded TS for

. reactivity. control based on the TSUP. working drafts.

Fuel Handling and Fuel Storage

' Fuel handling and fuel. storage operations will continue at FSV for an extended period after FSV's final shutdown. In order to defuel the reactor PSC must perform the equivalent of six refueling operations.

.The fuel. storage wells could be utilized to hold spent' fuel for the-remaining life of the current facility license and beyond. . In review of the continued fuel hand 1_ing and fuel storage operations, it is the graded. The staff staff.'s concursjudgement.that.the with.'the findings ofassociated TS1989 the April 19, should TERbe up(Attachrent) in this.

regard. Therefore, the-staff concludes that PSC should submit ~ upgraded TS for fuel handling and storage based on the TSUP working drafts.-

2.0' CONCLUSI0fl5 The staff concludes that the TSUP sections on Reactivity Control, Fuel Handling, and Fuel Storage should be upgraded in accordance with the TSUP working drafts. These TS should be fully _ implemented prior to commencement of-defueling' activities. The staff notes that these TS represent only a small fraction of the total TSUP, but have the highest impact on safety.

Dated: .__

Principle Contributor: Kenneth L. Heitner

Attachment:

Excerpt from draft TER I

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Attachment EXCERPT FROM DRAFT TECHNICAL EVALUATION REPORT ON TECHNICAL SPECIFICATION UPGRADE PROGRAM 3 .'4 . 9 FUEL HANDLING and STORAGE SYSTEMS 3/4.9.1 Fuel Handlina and Maintenance in the Reactor.

(Specification carryover from existing TS) The Fuel Handling and Maintenance in the Reactor section of the existing Specification LCO 4.7.1 was carried over and was substantially improved by upgrading to be more like the STS Refueling Operations Section 3/4.9. Improvements included separating out the startup channel neutron flux monitors (see the discussion under 2.2.1.9 below). The Applicability was clarified to "whenever both primary and secondary RCRV closures of any PCRV penetration are removed" versus the less clear existing Applicability of "during any irradiated fuel handling in the reactor vessel." The core average inlet l

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lc, te perature of 165'F was clarified as only being applicable when the Fuel Handling Machine is on the reactor ve:tel with both the cask isolation valve and reactor isolation valve open. The 165'F limit is to assure'FHM telescoping mast performance when it is inserted into the upper plenum of the reactor. Emphasis was added to maintain the Shutdown Margin by requiring its specification to be met and surveillance were added. This fuel Handling TS is consistent with FSAR Section 9.1.1, Fuel Handling During Refueling. This TS does not have a directly comparable section in the STS.

3/4.9.2 Instrumentation. (Specification carryover from existing TS) The specification for the startup channel neutron flux monitors during refueling was carried over from the existing Specification LCO 4.7.1.C and was substantially improved by upgrading to be more like STS Section 3/4.9.2. One improvement was specifying Applicability throughout the refueling mode and not just during irradiated fuel handling in the reacter. Action statements comparable to the STS were added for both one and two inoperable startup channels. These actions required imediate suspension of any controllable evolutions which could result in

ositive reactivity changes. Surveillance requirements for startup channel channel checks and functional tests were also added comparable to those in the STS. This startup channel neutron flux monitor TS is consistent with FSAR Section 9.1.1, Fuel Handling During Refueling.

3 /4. 9. 3 Fuel Handlino Machine. (Specification carryover from existing TS) The Fuel Handling Machine existing Specifications LCO 4.7.2 and SR 5.7.1 was carried over and substantially improved to specify additional requirements as embodied in the licensing basis in the FSAR Section 9.1.1, fuel Handling During Refueling. There is no STS equivalent to this specification. Specifications were added for the fuel handling purge system, availability of the gas waste system, augmented colling coil requirements, overhead crane attachment, and operable switches and alarms for verifying correct orientation and placement of fuel elements. The Applicability was extended to cover use of the FHM for reactor internal maintenance as well as handling of irradiated fuel. The Action statements

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arc surveillance were expanded to encompass the added specifications.

• dted surveillance included a 12 hour1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> verification of FhM internal

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cressure and' cooling coil water outlet temperature, testing of the FHM cask vahe and reactor isolation valve, inspecting the backup firewater connections, testing the fuel handling purge system and availability of the gas. waste system, and testing the overhead crane. These specifications on the FHM adequately address the. safety concerns of prevention of uncontrolled releases of radioactivity / radiation.during handling of irradiated fuel, maintenance of fuel element integrity by providing a cooling belium atmosphere and protection against mechanical camage. and correct installation of fuel elements into the reactor core.

3 /4. 9. 4 Fuel Storace Wells. (Specification carryover from existing TS) The Fuel Storage Wells existing Specifications LCO 4.7.3 and SR 5.7.2 was carried over'and substantially improved to specify added

- recairerents from FSAR Section 9.1.2, Fuel Storage and Associated fuel

, Handling. Although the STS has Section 3/4.9.11, Water Level-Storage Pool and 3/4.9.12. Fuel Storage Pool Air Cleanup System, these are not directly a;;1icatie since the FSV Fuel Storage Wells are a dry storage in a helium atmosphere. Specification 3.9.3.c was added to not allow irradiated fuel to be located in the central column of a fuel storage well.(irradiated fuel cannot be adequately cooled in the central column). Surveillance were added for daily checking of well pressure, coiling coil outlet temperature and flowrate, 31 day verification of emergency booster fan manual initiation, 18 month verification of the 9000 CFM air flow through the fuel storage facility, and verification of no irradiated fuel storage in the central columns of the wells.

Two relaxations of the existing Specifications LCO 4.7.3 and SR S.7.2 were accepted in the carryover to the TSUP. First, in LCO 3.9.3.b, TSUP, the required minimum air flow through the fuel storage facility was decreased from 12,000 CFM to 9,000 CFM. The 9,000 CFM air flow is the required minimum per FSAR Sections 14.6.3.2 and 9.1.2.3 to avoid significant fuel damage from overheating. Second, engineering evaluation was accepted as an alternative to establishing backup cooling.

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The licensee stated that the anticipated adiabatic heat up rate would be about I degree F per hour for a fuel element 100 days after removal from the reactor after full powcr operation. Anticipated small heatup rates allow adequate time to perform an engineering evaluation.

These fuel Storage Well specifications meet the FSAR Sections 9.1.2 and 14.6.3 requirements of maintaining the fuel element

. surface temperature below 750*F in a dry slightly subatmospheric

. helium environment.

3 /4. 9. 5 Seent Fuel Shineino task. (Specification carryover from existing 75) The Spent Fuel Shipping Cask existing Specification LCD 4.7.4 was carried over and was clarified to require 100 days decay of fuel before it would be loaded into the cask. An action statement was added to unload the cask if the fuel didn't meet the 100 days decay.

Also, a surveillance was added to the decay time on the fuel prior to loading. This specification on the Spent Fuel Shipping Cask complies with the requirements identified in FSAR Section 14.6.3.3, Fuel Shipping Cask Handling Accident. This specification is similar to the specification of 100 days decay time of STS Section 3/4.9.3, Decay Time.

3/4.9.6 Communications Durino Core Alterations. (Specification adapted from STS) The Communications During Core Alterations Section is new and was adapted from the STS Section 3.9.5. The only difference being that at FSV, control room two-way communications are established with the Fuel Handling-Machine control room as the center for refueling operations rather thlin the " refueling station" in the STS. As this TSUP section on communications is new and is adapted from the STS, it is acceptable.

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