ML20106C085

Technical Review Rept for Emergency Svc Water Sys on 840827-31

ML20106C085
Person / Time
Site:	Limerick
Issue date:	09/14/1984
From:	Higgins J, Wong S BROOKHAVEN NATIONAL LABORATORY
To:	NRC
Shared Package
ML20106C083	List: ML20106C085
References
NUDOCS 8410230643
Download: ML20106C085 (8)

Text

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BROOKHAVEN NATIONAL LABORATORY TECHNICAL REVIEW REPORT DATES OF INSPECTION: August 27-31, 1984 ORGANIZATION: Limerick Generating Station (LGS)

LICENSEE: Philadelphia Electric Company (PECo)

LOCATION: Limerick, PA BNL TECHNICAL SPECIALIST:

' ~J .

ggins I J!((

(Date)

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i Aldn S.M.Wopg Sh

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8410230643 841004 i DR ADOCK 05000 l i

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il.: Personnel Contiacted

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The following personsLwere contacted.during the-on-site. review of the LGS Emergency- Service Water :(ESW) System:

Reactior Engineer -

- USNRC

W._Borchardt J. Chung ..

Technical Assistant. USNRC

..A. Diederich_ Supervisor, Mech.~ Engr. PECo' ,

J. Doering- Operations Engineer- _ PECo

! .- D. Helwig. . Supervisor, Mech. Engr.

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. PECo L. Hopkins -- Perfcrmance Engineer PECo W. Kirschner -

Asst. Project Startup Engr.- Bechtel

.G..Leitch Plant Superintendent PECo C.-Lucha Startup Engineer . .

Bechtel

. S. Lynch Deputy Resident Project Engr. Bechtel K. Meck Quality Assurance Engineer- - PECo K. Murphy Technical Assistant USNRC J. Spencer Startup Director PECo.

Startup Group Supervisor - Bechtel.  ;

L. White-C. Wiedersum Mechanical Engineer PECo J. Wiggins Senior Resident Inspector - USNRC b 2.' Documents Reviewed The following materials or documents were reviewed:

(1) Limerick Final Safety Analysis Report (FSAR), Rev. 34 (2) Limerick Probabilistic Risk Assessment (PRA) i (3) Proof & Review Edition of Limerick Technical Specifications (Tech.

Specs.)',8/3/84 '

(4) . Emergency Service Water (ESW) System Description (5) Off-Normal, Operational Transients, and Trip Procedures

.(6) Limerick' Response Package for NRC Bulletin 80-06 I - (7) Limerick Safety Evaluation Report - -

(8) IEEE Standard 279-1971, " Criteria for Protection Systems for Nuclear l

Power Generating Stations" l ' (9) IEEE Standard 379-1972, "IEEE Trial-Use Guide for the Application of the 6

i. Single-Failure Criterion to Nuclear Power Generating Station Protection Systems" (10) - Procedures S11.8. A, B, C: Alternate Cooling of Reactor Enclosure Cooling Water (RECW) Heat Exchangers, Turbine Enclosure Cooling Water (TECW) Heat Exchanger, and Reactor Recirculation Pump Seal / Motor l Coolers.

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(l2) ' Flow Balance' Procedure: ESW, IFB54.1-0 (13) :Preoperational Test Procedure: ESW System,~ 1P-54.1-(14): Surveillance Te'st: ~ST-1-011-490-1, Rev.'0; ESW Valve Leakage Test ST-6-011-451-0, . Rev. 0; "A" Loop ESW Lineup  !

Verification  !

ST-6 011-401-0, Rev.' 0; "A" Loop ESW Valves Automatic' Actuation Test-ST-6-011-231-0,_Rev. 0 & Rev.' 1; "A" Loop ESW Pump, Valve & Flow Test (15) Limerick Tech. -Specs. Improvement Study (16) Peach Bottom Tech. Specs.

.(17) BWR Standard Tech. Specs.

(18) Piping & Instrumentation Diagrams: M-10, Nor:nal Service Water (NSW)

M-11, Emergency Service Water (ESW)

M-12, RHR Service Water (RHR SW)

(19) Startup Field Report: 54A-22 & 54A-25, Emergency Service Water

'(20) Startup-Test Change Notice: 1-12. Emergency Service Water (21) Startup-Test Exception Log: Emergency Service Water (22)_ Safety Evaluation Report (SER)'for LGS

3. Scope During this review of the Emergency Service Water System the following areas and items were addressed:

1. Preoperational Testing - including test procedures review, witnessing of system operation, and test results evaluation.

2. System Hardware Review - including a system walkdown and a review and evaluation of pumps, valves, piping, control room annunicators, con-trols, and indications, Remote Shutdown Panel controls and indica-tions, electrical supp!ies, spray pond, and cross-connects to other systems (NSW, RHR SW, TECW, RECW, and the Spent. Fuel Pool).

3. Operating Procedures Review - including system operations procedures, surveillance test procedures, inservice testing procedures, proposed tech specs, and alern response procedures.

4. Review of the above items against the major ESW system failure modes identified in the PRA to determine the extent that these failure modes have been minimized.

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L- ;4.JPlantTour

~ During the system review a tour was made..of the.ESW system.in order to de-m _stermine equipment and plant conditions. - The followinglareas- were observed:

7 @; - iControl ; Room, Remote Shutdown. Room. Aux 111ary Equipment Room,- RHR Pump Rooms,

Core' Spray; Rooms,. Reactor Core (Isolation Cooling (RCIC) Room, Spray Pond Pump f House, Spray Pond,; Pipe Tunnels, and ESW Valve Areas. With the exception of-C' '

items previously identified by the . licensee, equipment. appeared to be in ' good

, condition. - Overall. planticondition. appeared appropriate for th_e stage of con-1struction with;the exception of the control room cabinets which had an excessive

~Camount of. debris: including paper , loose fuses, fires-stop material, old tie s wraps, coils of; cable, and loose pieces of metal. The licensee cleaned the ESW l l

cabinets prior.to the completion of the inspectiori.

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5. Control-Boards 5 > '

e, The review of the ESW System included an evaluation of the control room and

. remote shutdown panel control boards to determine-their conformance with commit-1 ments made in the FSAR, their compatibility" with procedures,l and their o' verall

effectiveness for safe system operation. The panels appeared reasonably config-

ured.and < labeled for safe' operation despite their, lack- of an ESW system mimic.on - ~

! the panel. The annunciator panels were reviewed and comments 'are in paragraph 8 i

on procedures. The inside of system cabinets were observed. No lifted leads r

were 1dentified without proper. control tags. One loose untaped. spare lead was.

identified in the Remote Shutdown Panel. The licensee taped it promptly. One meter (FID-11-012A) was noted with confusing positive and negative scales.' The

, meter _ measures' differential ESW flow to give an indication of a system pipe _ ,

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. break. Control Room operators did not.know which end of the scale represented a ,

loss-of water. The licensee evaluated this and corrected the situation with red tape on the gage face to indicate that position of the positive scale which cor-responded to an unsafe situation (namely a pipe break). Finally, panel mounted

, gage calibration was reviewed and it was noted that some meters had calibrations

.over a year old. Upon questioning, it was determined that the licensee had not

. yet finalized a program, to determine instruments that must be recalibrated

, prior to fuel load.  ;

L f~ 6. System Design The actual ESW system design as installed in the plant and as described in

} system operating and test. procedures, and plant P&ID's was compared with the de-l

' sign of the FSAR, PRA, SER and pertinent industry standards listed in paragraph *

.2. With the exception of the below items no discrepancies or unsafe conditions were -identi fled.

i_ The ESW system consists of 2 loops, each with 2 pumps and is normally in standby. The ESW pumps are actuated in the event of a loss of offsite power or

• - a loss of coolant accident via signals from the diesel generators and the emer-gency busses. All- automatic ESW system valves are in turn actuated by contacts off the ESW pump breakers. That is, the. actuation signal for the system's

valves is?the'ESW pump start. Ther' are four ESW pumps (A, B, C and 'D) and.four corresponding divisions of automatic valves which realign the system to its safety configuration. -If the A ESW pump 'were to trip (opening the pump breaker F

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... .o and removing the valve actuation signal).all of the A' division valves automati--

=cally realign to their non-safety. position. This reduces the valving redundancy.

in the A loop although it does not incapacitate the loop. -This design arrange-ment also~ appears contrary to both IEEE-279 (1971), paragraph 4.16 and the guid-~

ance.of NRC.Bulletin 80-06. "ESF Reset Controls".= Specifically;-item-2 of the

. Bulletin specifies that all equipment should remain in its emergency mode upon removal of. the actuating signal; and paragraph 4.16 of IEEE-279 states that re-turn to operation (of the protectionisystem) shall; require subsequent deliberate operator action. ,

The ESW pumps-are located in the Spray. Pond Pump House in the Wet Pit, j which is supplied with water from'the cooling towers or directly from the spray pond. The' spray pond.is the seismic, safety related water. source. Water is de-i livered from the cooling' towers through -valves and from the spray pond through-motor-operated sluice gates. The control room operator. is provided with a low level alarm sensing spray. pond. level, however, there is no level instrument or alarm sensing Wet _ Pit level. . If the wet pit were isolated from the cooling

. towers and spray pond-(there have been sluice gate failures .during preoperation-

- al- testing), then the operator would have no . warning, prior to the ESW pumps failing to pump due to low suction pressure. Additionally, with-about 41,000 gallons in one wet pit and an average ESW loop flow of about 2900 gpm (or even less if -flow to room coolers is not needed due to cool temperatures) during Unit 1 operation, the operator would have sufficient time to react to a low level alarm. Thus although not a . regulatory requirement, it.' appears that a wet pit level detector and alarm could be a prudent ed.dition to the ESW/RHRSW systems.

7. Preoperational Testing The preoperational- test program for the Emergency Service Water (ESW) sys-tem was reviewed to ensure that proper operation of the system has been demon-

- strated. The objectives of this review included verification and assessment of r

licensee activities associated with the demonstration of:

1. ESW system capability to automatically supply cooling water to essen-tial safeguards equipment; and I- 2. The ability of system controls to function properly in the automatic mode and by actuation from the control rcom or the remote shutdown panel.

4 Based.on the audit of ESW loop A components in Preoperational Test Proce-dure IP-54.1, Rev. O, documenting the performance of the ESW system from 7/6/84 through 7/16/84, no discrepancies were identified with the exception of the fol-lowing items:

1. The closing times for Diesel Generator (0.G.) ESW Outlet valves (HV-L 11-132A, HV-11-132B, HV-11-132C, HV-11-1320, HV-11-134A, HV-11-134B,

HV-11-134V,HV-11-1340) exceeded the maximum by 8-15L Also, the closing times for TECW motor-operated valves (HV-11-107, HV-11-105, HV-12-110) exceeded the' maximum by 43-56L The opening times for the same valves exceeded the maximum by SOL I

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l There was no' functional testing ~-(stroking, cycling, .or. _ leak rate test-

< 2.1 ing) of_ system check valves documented during the preoperationa1E tests. Also there was no cycling documented for manual' valve 1006, a 8 '

main' header stop valve.- l

-3. _ The pump discharge flowrates were demonstrated to be 3900 gpm, 2700 ~

~ gpm, 3000 gpm and 2900 gpm for pumps '0AP548,: 0BP548, .0CP548 and 00P548 respectively. These _ flowrates are lower than the design flowrate of -

6400 gpm for;each pump. The full capacity' requirements-for supply to.

4 0.G.'s and ESW loop-A equipment exceeds 4000. gpm for unit 1 opera--

tion-and is considerably. higher if_ two unit operation or supply to

!. non-essential _ components. is considered.

Licensee Response:

In the case of item 1, the excessive stroke times forIthe. valves-in concern appear to be system specific. . This matter is_being addressed by PECo/Bechtel

. engineering staff. as documented by Startup Field Reports. For item 2, system check valves will be tested as-part of_ Limerick,In'-service Inspection; Program.-

The licensee's ' representative stated that they would corisider running this test 2

for the check valves prior to fuel load. In tne case of item 3,.PECo/Bechtel Startup Group at Limerick will write a procedure and perform a test to demon--

strate the full-load capability of theLsystem, and/or. establish the'11mits of cooling supply requirements for. different flowpaths. This test should be per-formed _for each pump using conservative loads and the most restrictive

! flowpaths.

8. System Operation

!- The plans for ESW system operation as outlined in plant procedures and L

4 training documents were reviewed. Specific findings follow.

i During a review of the PRA and system P&ID's, a number of valves and con-trol room hand switches were identified as being locked. It was determined that the program for. lock / key control for control room handswitches was not finalized ,

and that system valve lineup check-off-lists did not fully reflect the valve locking comitments.

The licensee uses Annunciator Response Cards (ARCS) to describe control room alarms / annunciators and to specify operator action in response to these.

t The ARCS being used in the control room for the ESW system were reviewed for technical adequacy and a number of errors and omissions were identified. The licensee stated that those ARCS had not yet been formally approved. During the

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' -week, the ESW ARCS were rewritten, reviewed, and approved to address the identi-fled concerns. Other system ARCS are _ scheduled for review and approval prior to fuel load. One item of particular concern in a number of cases, in the ARCS, was the lack of alarm setpoints as committed to in Chapter 13 of the FSAR..

During the review of the operating procedures it was noted that there were l no off-normal procedures for the ESW system to address potential situations such i

as realignment on loss of an ESW loop or use of normal service water on failure ll of the ESW system. It was also noted that the potential exists to supply any l Diesel Generator (D.G.) with ESW from either or both ESW loops. If a D.G. were i .

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' aligned to both loops simultaneously, a: single failure at a D.G. could fail'both .

ESW loops. There were no interlocks or procedural precautions to prevent.this line-up. After this was identified during the week, the licensee had permanent signs made up and installed on the control bcard to warn against this line-up. ,

i Du~ ring a review of the Draft Technical Specifications for ESW it was noted that' allowable ESW pump. outage times appeared excessive as compared with BWR Standard. Tech Specs and.with outage times assumed in the _ Limerick PRA. The licensee' stated that the ESW system is one system with four-pumps designed to.

- serve both units at Limerick. However, all four pumps are installed and are to be'available to serve only Unit 1 during the period before Unit 2 is to be oper-ated.- Thus due to this extra. equipment, the Tech Spec outage times were increased. In light of this method of. drafting the Unit _1 Tech Specs for shared Unit 1 - Unit:2 systems,-it appears that _a thorough review of Limerick Unit 1 Tech Specs for shared systems will be required before Unit 2 becomes operational.

9. Surveillance Testing The ESW system surveillance testing, planned for implementation once the >

plant - is operational, was' reviewed. Surveillance procedures for Technical Spec-ifications and Inservice Testing per the ASME Code,Section XI were reviewed.

With the exception of-the below items, which were corrected during the review, no discrepancies were identified.

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Procedure ST-6-011-231, Rev. O, " Pump, Valve, and Flow Test" had three discrepancies:

1. Step 6.5.4 in the procedure called for a pump flow of 3000 gpm, while step 6.5.4 in the data sheet called for 2600 gpm.

2. Check valves number 1011, 0064A, and 0065A were not tested.

3. .The procedure used visual observation of the check valve manual opera-tion levers to verify proper check valve stroking. However, discus-sions with the system startup engineer during.the system walkdown dis-j closed that the levers do not move as the valves stroke.

The procedure was revised and re-approved to correct these problems.

10. Summary of Findings l

10.1 Open Findings c Below are listed in summary fashion the items identified which were not i resolved during the review.

1. Dirt and debris in control room cabinets (para. 4)

2. .Recalibration of panel-mounted instruments (para. 5)

3. Automatic return of ESW valves to non-safety position (para. 6)

4. Lack of level detector / alarm for Wet Pit (para. 6)

5. Ability of one ESW pump to provide design flow rate (para. 7) r _ ,, -

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. . .. x-6.- No preoperational test of ESW check valves (para. 7)-

7.- Setpoints-not included in all Annunciator' Response Cards (para. 8) 8.- No off-normal procedures for ESW (para. 8) .

9. Program for locked valves and control room keylocked handswitches 0

'(para. 8)

10.  ; Technical Specification Outage 4 tine review for shared systems (para. 8) >

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-10.2 Resolved Findings Below are listed in summary fashion the items identified which were cor-rected during the review. ,

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1. Loose bare lead in Remote Shutdown Panel (para..,5)

Confusing control -room indicator (phra. 5) / '; 2 '

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i. 3. Precaution for D.G. supply from both ESW loops (para. 3):

4. . Discrepancies-in ESW Surveillance-Test Procedure (para. 9) e b

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