IR 05000483/1986017

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Safety Insp Rept 50-483/86-17 on 860604-11.Violation Noted: Failure to Maintain Auxiliary Feedwater Actuation Sys Instrumentation Operable During Modes 1 & 2
ML20202B122
Person / Time
Site: Callaway Ameren icon.png
Issue date: 06/24/1986
From: Forney W, Little B
NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION III)
To:
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ML20202B103 List:
References
50-483-86-17, NUDOCS 8607100209
Download: ML20202B122 (8)


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U. S. NUCLEAR REGULATORY COMMISSION

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REGION III

Report N /86017(DRP) s Docket N License N NPF-30 Licensee: Union Electric Company Post Office Box 149 - Mail Code 400 St. Louis, M0 63166 Facility Name: Callaway Plant, Unit 1 Inspection At: Callaway Site, Steedman, M0 Inspection Conducted: June 4 through 11, 1986 Inspector g

u)lb a L B. H. Little j

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) pate Approved By: L0it,i L@ Chief W. L. Forney, e 2 /. / 7 # /-

Reactor Projects Section 1A Date Inspection Summary Inspection on June 4 through 11, 1986 (Report No. 50-483/86017(DRP))

Areas Inspected: A special unannounced safety inspection by the Senior Resident Inspector regarding the blocking of auxiliary feedwater actuation instrumentation and NRC Region III Management site visi Results: One apparent violation was identified (failure to maintain the Auxiliary Feedwater Actuation System instrumentation operable while in Modes 1 and 2 - Paragraph 2.).

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DETAILS 1. Persons Contacted D. F. Schnell, Vice President, Nuclear

  • S. E. Miltenberger, General Manager, Nuclear Operations
  • G. L. Randolph, Manager, Callaway Plant
  • C. D. Naslund, Manager, Operations Support
  • A. P. Neuhalfen, Manager, Quality Assurance
  • J. D. Blosser, Assistant Manager, Operations & Maintenance
  • J. R. Peevy, Assistant Manager, Technical Services
  • M. E. Taylor, Superintendent, Operations
  • Denotes those present at one or more management interview In addition, a number of reactor operators, senior reactor operators, and other operations department personnel were contacte . Inspection of Auxiliary Feedwater Pumps (AFP) Engineered Safety Features Actuation System (ESFAS) Blocking Background On May 31, 1986, the licensee determined that the plant was in a condition prohibited by Technical Specification (T/S) Limiting Conditions for Operation (LCO) 3.3.2, " Engineered Safety Features Actuation System (ESFAS) Instrumentation". The violation occurred when the Auxiliary Feedwater Pumps (AFPs) ESFAS Blocking Switches (FC-HS-25 and FC-HS-26) were left in the " Block" position after the first main feedwater pump was put in service. The " Block" position placed the Auxiliary Feedwater Actuation System-Motor (AFAS-M) in a degraded condition such that the automatic start of the AFPs on loss of the main feedwater pumps was defeated. The prohibited condition existed for approximately 11 hours1.273148e-4 days <br />0.00306 hours <br />1.818783e-5 weeks <br />4.1855e-6 months <br /> when, during a control board inspection,areactorogeratorobservedthattheESFASblocking switches were in " Block . The ESFAS blocking switches were then placed in " permit" restoring operability of the AFAS-M, and satisfying the operability requirements of T/S 3. The licensee issued Incident Report No.86-144, dated May 31, 1986, i which documented the violation and declared the event as a Potential Licensee Event Report (LER) No. 86-018-0 A special safety inspection by the senior resident inspector was i

performed to assess the licensee's activities associated with the blocking of the AFP ESFAS. The inspection included:

(1) The review of documentation; Final Safety Analysis Report (FSAR), Safety Evaluation Report (SER), Incident Report (IR)

No.86-144, and plant operating log.

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(2) Interviews with Operations Department personne (3) NRC/ Licensee meeting b. hspectionFindings Event Chronology May 30, 1986 The "B" main feedwater pump (MFP) tripped 3:30 P.M. CST resulting in an Auxiliary Feedwater Actuatio Both "A" and "B" AFPs (motor driven) starte Steam generator levels were restored in accordance with off-normal procedure OT0-AE-00001, "Feedwater System Malfunction".

May 30, 1986 The AFP ESFAS blocking switches FC-HA-25 and 5:43 P.M. CST FC-HS-26 were placed in the block position in preparation for MFP startup. Placing the switches in " block" was not a procedural action for the existing plant condition (Mode 2 with AFPs maintaining steam generator levels).

Blocking of the switches was done to avoid an AFAS-M actuation during the specified startup trip test of the MFPs. The blocking action was not logge May 30, 1986 The "B" MFP was placed in service. Both "A" and 7:51 P.M. CST "B" AFPs were stopped. The blocking switches were left in " block".

May 31, 1986 The off going R0, during a control board walkdown 6:48 A.M. CST prior to shift turnover, observed the mispositioned blocking switches, notified the SS, and placed the switch in " permit" terminating the violatio Through document review and personnel interviews, the inspector determined that the violation resulted from a combination of procedure deficiencies and personnel performance error (1) Procedure Deficiencies Plant off-normal procedure OTO-AE-00001, "Feedwater System Malfunction", provides brief instructions for loss of main feedwater pump (s). The procedure specifies starting AFPs and restoring steam generator levels to normal. The procedure does not provide recovery instructions nor reference recovery /

restart procedure _

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General Operating Procedure OTG-ZZ-00003, " Plant Startup Below 5% to 20% Power", Step 4.2.3 provides instructions to start a MFP in accordance with OTN-AE-00001, "Feedwater System", Step 4.2.4 specifies stopping the motor driven startup feedwater pump after the MFP is in service. The procedure provides no instructions regarding the AFP ESFAS blocking switche Normal Operating Procedure OTN-AE-00001, "Feedwater System",

Section 4.3 (MFP Startup) provides instruction for startup, testing (trip), and placing the MFP in service. This section provides no instructions regarding the AFP ESFAS blocking switches. Subsequent sections do provide blocking switch instructions and is the normal method for plant startup:

OTN-AE-00001 - Section 4.5 (Maintaining steam generator (SG) levels with the startup (SU) feedwater pump)

" Caution - Ensure FC-HS-25 and FC-HS-26 (AFP ESFAS

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Blocking Switches) are in the block position (this prevents an inadvertent AFAS due to both MFP turbines being in a tripped condition". l OTN-AE-00001 - Section 4.6 (Shifting from the startup main feedwater pump to the main feedwater pump)

Step 4.6.1 - Ensure Section 4.3 MFP SU is complet Step 4.6.2 - Place FC-HS-25 and FC-HS-26 AFP ESFAS Blocking Switches in the " permit" position.

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The inspector determined that plant procedures applicable for transferring from the auxiliary feedwater pumps to the main feedwater pump failed to provide procedural control of the AFP ESFAS blocking switche In addition, the existing plant startup procedure (OTN-AE-00001) which permits the blocking of the AFP ESFAS switches, is not compatible with T/S in that blocking switches FC-HS-25 and FC-HS-26 renders all four AFP-M channels inoperable. T/S 3.3.2 requires that the Engineered Safety Features Actuation System (ESFAS) instrumentation channels shown in Table 3.3-3 be Operable. Table 3.3-3 Function Unit (auxiliary feedwater) 6.g. (Trip of All Main Feedwater Pumps - Start Motor Driven Pumps (Auxiliary Feedwater Pumps (AFP)) requires a minimum of three channels operable in Modes 1 and (2) Personnel Performance Errors (a) Placing the AFP ESFAS Blocking Switches in " block" was not a procedural action, thus negating procedural control of these switche t

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(b) Blocking the AFP ESFAS was not logged; failure to log placing the switches in " Block" defeated an opportunity of detection during shift turnover log revie (c) Control board walkdowns during the shift change at 11:00 P.M. on May 30, 1986, (specified in Operations Department Procedure ODP-ZZ-00003, " Shift Relief and Turnover"), failed to identify / recognize the T/S violatio Indication provided on the control board:

Panel RL027/28 Two AFP ESFAS BLOC switch positions Train A FC-HS-25 " BLOCK" Train B FC-HS-26 " BLOCK" ESF SYS STATUS Panel Six red lights - (three each train)

Aux Actuate FW SYS Loss of MFP TURB BLOCK c. Safety Reports SNUPPS Final Safety Analysis Report (FSAR), Chapter 7 provides AFS description. SNUPPS FSAR, Chapter 15 provides AFS safety analysis for loss of normal feedwater flow and feedwater system pipe brea Applicable FSAR sections are attached. No credit is taken in the analysis for automatic start of the AFPs on loss of main feed pump In the Callaway Safety Evaluation Report NUREG-0830, dated October 1981, the staff considered the initiation of the AFS on loss of the MFPs as an " anticipatory signal" for which no credit was taken in the analysis. However, the staff specified that the design included appropriate features to ensure that the block is removed to provide

! AFS initiation on loss of main feedwate d. Safety Significance Plant operations, while the AFP ESFAS blocking switches were in the

" block" position, resulted in the Auxiliary Feedwater System (AFS)

being in a degraded condition such that automatic start of the motor

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driven auxiliary feedwater pumps on loss of the MFPs was defeated.

l However, the AFS was operable in all other aspects and would have l responded to safety injection, loss-of-off-site power, Lolo steam generator levels or manual initiation signals.

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While the lack of the automatic start feature of the AFPs on MFP trip posed no significant threat to public/ plant safety, the event is considered significant based on procedural and personnel performance deficiencies, which placed the plant in a condition prohibited by Callaway Technical Specification Callaway plant records show that the plant operated in Modes 1 and 2 from 7:51 pm CST on May 30, 1986 until 6:48 am CST on May 31, 1986, a period of approximately 11 hours1.273148e-4 days <br />0.00306 hours <br />1.818783e-5 weeks <br />4.1855e-6 months <br />, with all four channels of AFP ESFAS " blocked" inoperable. The licensee's failure to maintain the AFP ESFAS operable while in Modes 1 and 2 is a violation of Technical Specifications Limiting Condition for Operation 3. No. 483/86017-01(DRP)

3. NRC Region III Management Site Visit On June 10, 1986, the resident inspectors accompanied NRC Region III Management (Messrs. A. Bert Davis and R. F. Warnick) on a plant tou The tour included an inplant walkdown and interviews with licensee's operating staff. General observation are as follows:

Plant Conditions indicate that good housekeeping practices are being implemente Control room personnel were attentive and knowledgeable of plant conditions and control room activities were being conducted in a business-like manne Operating crew personnel displayed a positive attitude toward plant operations in general, and a personal determination toward event reductio NRC observations were discussed with the licensee in an exit meeting following the visit. During this meeting, the licensee discussed progress made in reducing the number of reactor trips and Licensee Event Reports and licensee's event reduction programs in place. The discussion l

focused on personnel errors in general and specifically on the blocking of the AFP ESFA This discussion included the licensee's safety

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assessment, root cause, andcorrective action Corrective action l includes the following:

TAKEN PLANNED .

Use of the switch in Modes A proposed T/S change will

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1 and 2 has been prohibited be initiate by Night Orders until a T/S interpretation is issue Applicable procedures will be revised to address the various i Operations personnel have been pump shifts.

l instructed to take prompt action I to bring procedure anomalies to Operations personnel will be the attention of superviso briefed on the liabilities of taking action outside of t

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Letters to all Operations procedure personnel concerning attention to control board indication have The procedure change will include been issue a note to identify the potential for an AFA The operators will be instructed about " unplanned actuations".

The inspection has shown that the licensee identified and documented the violation. The violation once identified, was given prompt and thorough management attention. Licensee's corrective actions appear adequate to prevent recurrence. The effectiveness of these actions will be assessed in subsequent NRC inspection . Exit Interview The inspector met with licensee representatives (denoted under Persons Contacted) at intervals during the inspection period. The inspector sunnarized the scope and findings of the inspection. The licensee representatives acknowledged the findings as reported herein. The inspector also discussed the likely informational content of the inspection report with regard to documents or processes reviewed by the inspector during the inspection. The licensee did not identify any such documents / processes as proprietar . Enforcement Conference An Enforcement Conference was held on June 3, 1986 at the NRC Region III office, Glen Ellyn, Illinois between Mr. D. F. Schnell and members of the Region III staf D$ ring the meeting the Licensee presented facts relative to an event lon April 12, 1986, discussed in Inspection Report No. 50-483/86010. Messrs. A. Bert Davis and Robert F. Warnick of the NRC Region III staff con}ucted a site visit and tour on June 2, 1986. During the visit Mr. Steve fliltenberger and other members of the Licensee staff presented facts relative to the May 31, 1986 event, discussed in paragraph 2 above. The Licensee presented background information, corrective action to prevent recurrence, and potential mitigating facts which the NRC will use to determine the appropriate enforcement actio On JJne 23, 1986, Mr. William L. Forney of the Region III staff called Mr. D. F. Schnell to discuss the i.eed te conduct an additional Enforcement )nference. Mr. Schnell declined his option to attend an Enforcement nference stating that all cf the pertinent facts had been presented to 'essrs. Davis and Warnick during their site visi .

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Attachmenti SNUPPS FSAR Section 7.3.6.1. ,

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ATTACHMENT l

. SNUPPS l l

I (( control panel. The AFS flow to each steam generator is indi-cated on both the main control board and at the auxiliary shutdown control pane The AFS equipment is described in Section 10. In addition to initiating functions described above, the auxiliary feedwater actuation signal (AFAS) closes the steam generator blowdown and sample isolation valves, when auxiliary feedwater is required by plant conditions. All remote manually operated valves in the normal suction from the CST and in the discharge to the steam generators are normally ope .3.6. System Description Initiating circuits The motor-driven pumps are started on the occurrence of any one of the following signals: Manual start Safeguards sequence signal (initiated by safety injection signal or loss-of-offsite-power) Auxiliary feedwater actuation (AFAS-M)

AFAS-M is generated on the occurrence of any one of the following events: Trip of both main feedwater pumps (Manual block of the main feed pdmp trip signals is provided at the main control board, and is indicated on the ESFAS status panel. This block permits ,

startup and shutdown of the plant without automatic start of the Al- while allowing the AFPs to remain available to respond to a demand from any other source.) out of 4 low-low level signals in any one steam generator

Manual AFAS-M initiation The turbine-driven pump is started on the occurrence of either of the following signals: Manual start Auxiliary feedwater actuation (AFAS-T)

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Rev. 8 7.3-19 2/82