ML20198C407

Requests That NRR Review Basis of TS 2.16 to Determine If Basis Represents Nonconservative Approach to Safe Plant Operation

ML20198C407
Person / Time
Site:	Fort Calhoun
Issue date:	06/22/1990
From:	Collins S NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION IV)
To:	Boger B Office of Nuclear Reactor Regulation
References
NUDOCS 9107020440
Download: ML20198C407 (21)

Text

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c#*%4 UNITED STATES g

% NUCLEAR RE'GULATORY COMMISSION

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. . nEGloN IV 611 RYAN PLAZA DRIVE. SUITE 1000

% ARLINGTON, TEXAS 76011 JUN 2 21990 MEMORANDUM FOR: Bruce Boger, Acting Assistant Director, Division of Reactor Projects, Project Directorate IV FROM: Samuel J. Collins, Director, Division of Reactor Projects, Region IV

SUBJECT:

REQUEST FOR REVIEW 0F THE FORT CALHOUN STATION (FCS)

TECHNICAL SPECIFICATIONS (TS)

During the 1989 sumer months, the licensee experienced problems with low Missouri River levels. To address the poteritial for low levels, the licensee revised Procedure A0P-01 (Attachment 1) to specify what actions would be taken at various levels. Note that many of the actions specified are based on the level in the cells of the intake structure instead of the level in the river.

During various times of the year, the screens for the intake structure cells can become clogged with debris or ice. The clogging can result in the level in a cell being significantly lower than the level in the river. Data s recorded by the licensee (Attachment 2) indicate that cell level may be as much as 17 inches below river level.

The LCOs in TS 2.16 are based on the level of the river. It appears that using the river level as a basis of the limiting condition for operation may be nonconservative since cell levels may be significantly lower. The licensee addressed this apparent nonconservatism in a memo (Attachment 3).

It is requested that NRR review the basis of TS 2.16 to determine if the basis represents a nonconservative approach to safe plant operation. If it is determined that a nonconservative basis exists, it is requested that NRR pursue a TS change with the licensee. The Region IV contact w'th regard to this request is Les Constable (FTS 728-8151).

oe D'/L

v. C llins, Director

' Division of Reactor Projects Attachments:

1. Parts of Procedure A0P-1,

" Acts of Nature"

2. Missouri River Data

3. OPPD Internal Memorandum, dated December 22, 1989 l

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cc w/attacnments:

P. Harrell 9107020440 910622 R. Azua PDR ADOCK 05000285 L. Constable P PDR D. Dudley, PDIV-1, NRR A. Bournia, PM, NRR l I

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-Fort Ceihoun Station Unit No. 1 4

AOP-01 ABNORMAL OPERATING PROCEDURE

Title:

ACTS OF NATURS Setpoint/ Procedure Form Number (FC-68). 30273 Reason for Change: AOP Upgrade Project. To convert from a single-column narrative format to a two-column instruction / contingency action format as required by EOP/AOP Procedure Generation Package

(" Writer's Guide") .

Contact Person: Greg Gullani l-l-

Rev. No. O. -

ISSUED: 01-04-90

. . .. - .. . . - . .- --. . - . . = . - _ - . - . -. .- - . _

s A

f AOP ACTS OF NATURE TABLE OF CONTENTS TITLE PAGE NO.

l- ~SECTION I FLOOD. . . . . . . . . .......... . . . 2' SECTION'II SECTION III~

TORNADO. . . . . . . . . . . . . . . . . . . . . . . . 6 SECTION IV EARTHQUAKE .. . . . . . . . . . . . . . . . . . . ... 9 LOW RIVER LEVEL. .. . . . . . . . . . . . . .. . . . .

12 Attachment 1 Strong Motion Acceleration System SMA-3. . . . . . . .

24 Attachment 2 Intake Checks For low River Level. . . . . . . . . . 26 Attachment 3 Flocaing Intake Cell C from Cell B . . . . . . . . . .-28 c

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FC/AOP/01A AOP-01 e PAGE 1 0F 28 RO i

1

. . _ . _ . . _ . . ~.

s SECTION IV - LOW RIVER WATER LEVE(

1.0 PURPOSE The purpose of this section is to describe the steps which must be taken in the event of low river level, including guidance for ice conditions.

2.0 ENTRY CONDITIONS One or more.of tre following conditions may exist:

a.

U.S. Army Corps of Engineers forecasts the possibility of river-level falling below 983 ft 0 inches.

' b.

Actual river level has fallen below 983 ft 0 inches as verified from'the intake-structure.

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l FC/AOP/01A AOP-01 PAGE 12 0F 28 Ro

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1..

SECT 10N TV - LOW RIVER WATER LEVEL (Continued)

(NSTRUCTIONS CONTINGENCY ACTIONS l

'3.1 I MONITOR Circulating Water Pump - '

operation, Raw Water Pump operation, and grid / screen

-differential pressures for possible. loss of suction.

RQIE Operations Management will inform the U.S. Army Corps of Engineers that the FCS low river level administrative limit has been reached  !

when river level is ;982 ft 0 inches and request increased river flow from Gavins. Point. The Corps of Engineers can be reached during norma; business hours at (402) 221-7354. The Omaha District: Emet gency Response Management Team is available 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> per day at (402) 221-4148. This number is a recording'where a message is left and then the appropriate person is paged to return the call. -982 ft 0 inches was established as an administrative river level limit on 11/14/1989 by memo PEO-SSE-89-9535.

IF river level'goes to

-3. 2 1982 ft-0 inches, THEN the Shift Supervisor will perform the following:

a. NOTIFY Operations .

Management of requirement to contact U.S. Army Coros of Engineers,

b. NOTIFY the Resident or

Senior Resident NRC Inspector.

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l FC/A0P/01A AOP-01

{ PAGE 13 0F 28 RO

SECTION IV - LOW RIVER WATER LEVEL (Continued)

[NSTRUCTIONS CONTIN Gn,T ACilnNS 3.2 Continued

c. NOTIFY NRC Operations Center per Standing Order R-11, Notification Of Sionificant Events based on a potential _

press release from the U.S. Army Corps of Engineers.

NOTE Control Room river level indication can be used for the purpose of maintaining a continuous river level watch so long as it is able to provide indication of a sudden drop in river level. However, s in order to rely on this indication for the purpose of initiating preplanned than 3 inchas.

ictions, it can t10_T differ from actual level by more

d. Compare ERF Computer river level indication with level 'eading taken locally. -

3.3 J_F, Circulating Wa .er or Raw Water are lost, T.lEN IMPLEMENT A0P-10, Loss of C rculatina _

Water or A0P-18, ! oss of Raw Water, respective'y.

3.4 JF,F conditions are present fo.

ice formation on the traveling i

screens, THEN OPERATE the screens in " MANUAL FAST" or

" MANUAL SLOW" as necessary.

FC/A0P/01A AOP-01 PAGE 14 0F 28

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SECTION IV - LOW RIVER WATER LEVEL (Continued)

INSTAtTTIONS CONTINGENCY ACTIONS

+

NOTE The continuous river level watch can be stationed in the Control Room or the intake Structure. This person will monitor river level and pump performance and will warn the shift supervisor of any sudden loss of water supply. (Tech. Spec. 2.16(2))

3.5 IE the river level goes to y,980 ft 0 inches, THEN .

perform the follcuing:

a. ESTABllSH a continuous river level watch in the Control Roots or the Intake Strutture.

b. Shift Supersisor will notify the Fesident or Senior Resident NRC Inspector.

I

c. g!AECT the luxiliary J

Operator Nuclear or the contiruous river level waten (if stationed in the Intake structure) to perform peri:dic cell level checks per Attachment 2 at least every 60 minutes.

I O

FC/AOP/01A AOP-01

• _ ,,,PAGE 15 0F 28 R0

SECTIONIV-LOWRIVERWATERLEVEL(Continutil INSTRUCTIONS CONTINGENCY ACTIONS

.. 3.5 Continued

d. lE an ice jam develops, as indicated by visual sighting or an unexpected decrease in river level, THEN Shift Supervisor vill notify U.S. Army I:)rps of Engineers.

((402)453-2202) 3.6 Jf; the operator performing Attachment 2 reports exceeding any cf the following limits for low cell level, THEN perform the designated action:

a. 1F any cell level is 1979 ft 0 i1ches, THEN perform actions for river level 1979 ft 0 iiches (Step 3.7).

b. JfL Cell A level is 1978 ft 0 inches OE -

Cell C levei is 1977 ft 4 inches, THEN perform actions for river level 1978 ft 0 inches (Step 3.8).

FC/A0P/01A AOP-01 PAGE 16 0F 28 R0

. i SECTION IV - LOW RIVER WATER LEVEL (Continued) _

TNSTAUCTIONS CONTINGENCY ACTIONS

. 3.6 Continued

c. E Cell A level is 1978 ft 0 inches AND Cell C level is 1977 ft 4 irches, THEN perform actions for river level 1977 ft 4 itches (Step 3.9).

d. E any cell level is 1976 ft 9 inches, THEN perform the following:

i) ATTEMPT TO restore level in the affected cell by stopp11g the Circuliting Water Pump rinning on that (.11! and by backweining the GRIDS, if necessary.

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1 AOP-01 FC/AOP/01A PAGE 17 0F-28 R0

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SECTION IV - LOW RIVER WATER LEVEL (Continued)

INSTDilCTIONS CONTINGENCY ACTIONS

. 3.6 Continued ii) E the cell level is NOT restored, THEN start a Raw Water Pump in a cell alth level

>976 ft 9 inches ANO stop the affected Raw Water Pump.

iii) E the cell level can NOT be maintained

>976 ft 9 inchet, THEN the Shift Supersisor will determine Raw Water system operability and ,

take L 0 actions per Technical Specification 2.4(1):,

" Containment -

Cooling".

4 FC/AOP/01A AOP-01 PAGE 18 0F 28 R0 t

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SECTION IV - LOW RIVER WATER LEVEL (Continued)

INSTRUCTIONS

/ CONTINGENCY ACTIONS

+ 3.7 JL the river level goes to 1979 ft 0 inches, THEN perform the following:

a. Shift Supervisor will notify the Resident or Senior Resident NRC Inspector o' river level.

b. Shift Supervisor will verify operability of Raw Water System checking Raw Water flow

>4200 gpm in the same manner as determined for the Raw Water System on FC-75, Control Room loo,

c. THROTTLE cor. denser flow to prevent Circulating Water Pump Cavitation and to lower grid and screen differential pressure.

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i FC/AOP/01A AOP-01 L

PAGE 19 0F 28 RO

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l SECTf0N IV - LOW RIVER WATER LEVEL (Continued) -

INSTRUCTf0Ee CONTfNGENCY ACTIONS r

EIE

~

c Actions taken at 978 ft 1 inches river level are anticipatory based on the need to have the plant in Cold Shutdown orier to 976 ft 9 inches river level.

dropped 4 feet over a three daData shows the river has ;.- eviously decrease was 1 inch per hour. y period. The maximum rate of level 3.8 jf. the river level goes to 1978 ft 0 inches, THEN perform the following:

a.- REFER T0 the Emergency Plan. -

b, COMMENCE plant shutdown

~

to Cold Shutdown at a

) rate sufficient to ensure the slant is in Cold Shutdown before-river level reaches 976 ft 9 inches.

c. REFER TO Technical Specification 2.19(4)a for 1 fire pump inoperable.

d. NOTIFY the City of Blair -

Fire Department to assemble eqaipment for the impending loss of

fire suppression water

} '. system at FCS.

( -) ((402)426-6866).

d FC/AOP/01A AOP-01 PAGE 20 0F 28 9 RO 9

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SECT 70N IV - LOW RIVER WATER LEVEL (Continued)

INSTRUCTIONS CONTINGENCY ACTIONS

.. 3.8 Continued f- e. jDi21 j the Circulating Water Pump in the cell with the operating Raw

, ' Water Pump QR shift to a Raw Water Pamp in a cell without an 7perating Circulating Water Pump.

f. THROTTLE ot.1er Circulating Water Pump ~

flows to prevent the operating pamps_from cavitating.

)

3.9 1F the river _ level goes to 1977 f t 4, inches, THEN perform the.following:

a. Shift Supervisor will notify Resident or Senior Resident NRC Inspector of river

-level.

b. REFER TO Te:hnical Specification 2.19(4)b for no fire suppression e

{' water system operable.

h t  !

FC/AOP/01A AOP-01 PAGE 21 0F 28 R0

\

i SECTION IV - LOW RIVER WATER LEVEL (Continued)  !

INSTnUCTIONS CONTINGENCY ACTIONS 3.9 Continued

_ NOTE Fire header supply must be established from a backup source during low river level conditions to ensure alternate CCW cooling and EFWST emergency fill capabilities are maintained,

c. ESTABLISH backup fire protection by contracting the Blair Fire Department for a pumper truci draft from the river on to connect the Training Center fire suppression water supply (approximately 150,000

gallons filled from the City of Blair water supply) to any fire '

hydrant on site

((402) 426-6866).

3.10 1E the river level goes to 3.10 1E the plant is NOT in Cold f 1976 ft 9 inches, THEN perform Shutdown, THEN use a main the following:

condensate pump from the a.

hotwell or the CST to maintain VERIFY the plant is in Emergency Feedwater Storage Cold Shutdown.

Tank level OR implement

- A0P-30, Emeroency Fill of

b. REFER TO the Emergency Emeroency Feedwater Storace Plan.

Tank.

FC/AOP/01A AOP-01 PAGE 22 0F 28

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SECTION IV - LOW RIVER WATER LEVEL (Continued)

) INSTRUCTIONS CONTINGENCY ACTIONS 3.10 Continued

c. E a single Raw Water ~

Pump stops 1. umping, THEN '

attempt to restore Raw Water with the other pumps.

d. E Raw Water is lost, THEN implement AOP-18, loss of 2aw Water AND attempt to iestore Raw Water and F:re Protection iater by flooding Ce',1 C from

) Cell B per /ttachment 3.

3.11 WM.N. river level r eturns to 2,983 ft 0 inches, THEN EXIT this procedure.

FC/AOP/01A AOP-01 PAGE 23 0F 28 RO v ,s.--,--N.--as,--- .----,--,-.-,,+,w.w.,..,.-,n--,. , .r-.-,e---. , +,.n,--v w,-~. ~,m,v ~-w--,w vm.-,,e--e w,-. ,s-wn.,-.-v,--a,ge-, e,w----v---s-e=,-en

4 ATTACHMENT 2 I

INTAKE CHECKS FOR LOW RIVER LEVEL '

1.

Record data on Low River Level Log Sheet every 60 minutes or more frequently if desired.

t 2.

IE the Missouri River level or any intake cell level drops to any of the following level limits QR drops from one of the limits to a lower limit.

THEN the Shift Suoervisor must be informed:

CELL LEVEL Any cell <979 0" Cell A 1978'O QR Cell Cs977'4" ,

Cell A 5978'0' AND Cell Cs977'4" Any cell 1976 9" RIVER LEVEL 1979'0" 1978'0" 1977'4" 1976'9" 3.

IF icing conditicus exist, THEN visually observe river each time data is recorded and notify Shift Supervisor if increased icing has occurred. ,

4.

Cell level may be obtained using either of the following methods: '

a. Cell Level u (River Level) - (Highest Grid DP for the Cell) -

(Highest Screen OP for the Cell)

b. Cell Level -

• ' (1007'6") - (Distance from Intake Floor to Cel.1

_W ater Surface)  ;

5.

1 If, remote river _ level-indication does NOT trend with actual river level, 1 c

THEN the Shift Supervisor must be notified.

I FC/AOP/01A A0P-01 '

PAGE 26 0F 28 R0

ATTACHMENT 2

)

INTAKE CHECKS FOR LOW RIVER LEVEL (Continued)

Low River' Level too Sheet Time Grid Diff.A. -

Grid Diff.B.

Grid Diff C.

Grid 01ff.0.

Grid Diff.E.

Grid Diff.F.

Screen Offf.A.

Screen Diff.B.  ! i i

Screen Diff.C. I I '

i Screen Diff.0. I i Screen Dif f.E. I l

! l Screen Diff.F. l l

) CR River level Local River Level Cell A Level Cell B Level I I i l Cell C Level l l .

NOTE This example shows cell level calculation:

Cell B Level = R - G - S, where:

R = River Level in feet and inches.

G = The highest differential pressure in inches on Grids C or D.

S = The highest differential pressure in inches on Screens C or 0.

AOP-01 FC/AOP/01A -

PAGE 27 0F 28 R0

.- e. , - -

ATTACHMENT 3 FLOODING INTAKE Cell C FROM CELL B NOTES 1.

The irlet of the intake structure is at the 970 ft 0 inch elevation, which is below the river bed elevation. The botton of the intake structure then slopes down to the 966 ft 2 inch elevation. Therefore, if any water remains in the rdver, the bottom of the cells should contain some water.

2. Cell .? or B level can be restored using the same strategy if Cell C level cannot be raised due to excessive gate leakage.

1.

CL21E Cell C Sluice Gates CW-14E and CW-14F.

2.

[LQ1E Cell C to Cell B Interconnection Gate CW-168.

3. ENSURE the following gates to other cells are open.

l CW-14A, Cell A Sluice Gate CW-148, Cell / Sluice Gate CW-14C, Cell E Sluice Gate CW-140, Cell B Sluice Gate CW-16A, Cell 5 to Cell A Interconnection Gate 4.

PLACE the submersible dewatering pump (s) into Cell B and attach power supply.

j 5.

Route the submersible pump (s) discharge to Cell C.

6. START the submersible pump (s) to flood Cell C.

7.

- WHEN water level (7 Cell C is high enough to sustain Raw Water Pump operation, THEN stirt Raw Water Pump AC-100 AND throttle Component Cooling Water HX valves to maintain Cell C level.

FC/A0P/01A AOP-01 PAGE 28 0F 28 RO

L . . . .

L-MISSOURI RIVER DATA -

e .

4 FLOW (CFS).. ELEVATION Lowest- Ice

l. Date/ Time Gavins Pt Omaha FCS Blair h ha I

Cell Leve1* Cover Coeuments  ;

1-23-90/1000 11,000' 14,000 984'6" 986'9" 957'10" E/983'1"

. ' < 5% Screen F isolated. Ice bridge i above FCS released yesterday

! afternoon.

1-24-90/1000' i 10,500 13,400 984'8" 986'9" 957'11" B/983'10' O Bay C isolated and de-watering to repair Screen F.  :

.l - 1-25-90/1000 10,500 13,000 984'3" 986'8" 958'0" B/983'2" 0 Bay C isolated for screen F repair.

i 1-26-90/1000 10,500 13,000 984'2" 986'6" 957'11" B/982'11" Bay C isolated for screen F O

1 .

repair. -

1-29-90/1000 14,000 13,100 984'0" 986'6" 957'8" B/982'7" O Bay C isolated for screen F  !'

repair. Flow increased to 12,500 CFS over weekend and to 14,000 CFS this morning. ,

1-30-90/1000 14,000 14,000 984'5"- 986'10" 958'0" B/983'4" 0 Bay C isolated for screen F repair.

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i c: R. L. Jaworksi R. W. Short j G. R. Peterson A. G. Koenig ,

J. D. Kecy C. F. Simmons

• River Level minus highest screen / grid DP

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l l Date: December 22, 1989

.n1 PED-SSE-89-10665' 1 Frora: R. L. Jaworski To: J. W. Chase

SUBJECT:

USAR/ Technical Specification Conformance with Low River Level Actions

REFERENCE:

AOP-1, Rev. 2," Acts of Nature" The purpose of this menn is to explain Station Engineering's position on Technical Specifications. apparent discrepancies petween the recently revised A for decreasing Missouri River levels.AOP-1 was revised to include the actions nece river and/or intake structure cell levels.The actions are to be taken at specific The cell levels were included to account for river elevation losses through the grids and traveling screens.

Technical Specification 2.16 states, "If the Missouri River level is less than operating procedures.976'9", the reactor will be placed in a cold shutdown cond will be maintained to assure no sudden loss of water supply oc Although the cell level directly affects the pumps (i.e., raw water, circulat-ing water and fire , the river level is the appropriate level to use to initiate actions. )The intent of the Technical Specification the plant is placed in a safe condition before the water supply is lost. The level or in a single cell msy drop temporarily due to debris or ice on the grids screens.

pump, plus raw Each water cell's pump, grids flowand of more screens than are designed for a circulating water is only a few thousand gpm; therefore 100,000 gpa, while raw water alone when a circulating water pump is stopped,differential.

pressure the remaining riw water pump, flow will create a negligible screen / gri level is adequate does not constitute a loss of water I- supply.Beca

• 'ctions taken to restore a cell level are not successful, the o .

take the appropriate action based on the affected cell.perater u 1cted to At this level, hourly cell level measurements will be taken satisfactory pump submergence.

If a cell level falls and remains below the river level had fallen to that level. specific predetermined levels as falls below 978'0", the plant will connance shutdown to cold shutdownAddition conditions.

before raw water pump air.imum submergence is reacher..This ass It is important to note and then as a proactive seasure, monitors cell levels a ensure additional levels of safety. Based on this discussion, the AOP-1 actions are consistent with the stated specification and the intent of that specification; therefore, no changes to the Technical Specifications are required.

M; e

4 s . '.

I _ _ .

J. W. Chase ~~

PED-SSE-89-10665 Page 2 Two USAR statements apparently conflict with the AOP-1 acti 2.7.1.2require normally states that that the plant any be water shutdown. level below ons. about USAR elevation Section 9 asl would

- river level during the winter is controlled higher than 983.0 feet.to at least an elevatien of 983.0 . .

orps of Engineers

, and "The feet; norma b

Engineers to maintain Although einimum agreement river water between levelsOPPO has not and bee the Corps of Engineers does cooperate with OPPD n formalized, in these the matte additional first statement is flow an u from upstream dans if such and would conditions ending."

provide The wo does not require anyfon.

staviin ac:isupported generality in the hydrology section w The other statements are unsupported under-action.gs change to at section the time 2.7.1.2 o.' plant should construction delA USAR which change alsoshoul do n 903'0" normally requiring shutdown. ete the statement refarring to elevation ncies. A i reference to the Corps cf Engineers A change to section maintaining 9.8.6 should a specificdelete lev state that the Corps of Engineers adjusts winter .

It should releases fr necessary to accomodate the needs of all Missouri ns Point s.

River as water and do not conflict with AOP-1.In sumary, the Technical Spe have any questions rereflect actual Station practices end CoMinor ch Rick Sanchez (x6916).garding this memo,rps of Engineers 6

. L. awors h

Manager-Stay on Engineering progc.tionEngineringDivision

) RLJ RkS/ 57js c: Sudesh Gambhir Ken Morris Gary Peterson Jim Kecy Del Trausch Ken Hendry Bob Odden Carl Simmons Francis Buck Dan Johnson Al Koenig

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