ML20024H279

Proposed Tech Specs Changing Snubber Related Sections to Revise Visual Insp Schedule Per Generic Ltr 90-09

ML20024H279
Person / Time
Site:	Sequoyah
Issue date:	05/24/1991
From:	TENNESSEE VALLEY AUTHORITY
To:
Shared Package
ML20024H277	List: ML20024H276 ML20024H279
References
GL-90-09, GL-90-9, NUDOCS 9105310109
Download: ML20024H279 (21)

Text

_ . . . _ _ ___ _ _ . _ ___ __. _ . _ . . . _ _ _ _ _ _ _ _ _ _ _ _ _ . . . _ ._ . - _ _ _ . _ . _ _ . _ . _ _ . = _ . _ . _ _ _ . _. ._. ._

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ENCLOSURE 1 PROPOSED TECHNICAL SPECIFICATION CHANGE SEQUOYAH NUCLEAR PLANT UNI'IS 1 AND 2 DOCKET NOS. 50-327 AND 50-328 (TVA-SQN-TS-91-06)

LIST OF AFFECTED PAGES Unit 1 3/4 7-21 3/4 7-22 4 3/4 7-23 i B3/4 7-6 Unit 2 1 3/4 7-21 3/4 7-22 3/4 7-23 l 3/4 7-24 I

B3/4 7-6 B3/4 7-6a l

l 9105310109 910524 PDR ADOCK 05000327 p PDR 1

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PLANT SYSTEMS 3/4.7.9 $NUBBERS LIMITING CONDITION FOR OPERATION 3.7.9. All safety-related snubbers shall be OPERABLE. EC i

APPLICABILITY: MODES 1, 2, 3 and 4. (MODES 5 and 6 for snubbers located on J systems or partial systems required OPERABLE in those MODES.) l ACTION:

With one or more snubbers inoperable, within 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> replace or restore the inoperable snubber (s) to OPERABLE status and perform an engineering evaluation on the attached component or declare the attached system inoperable and follow the appropriate ACTION statement for that system.

SURVEILLANCE REQUIREMENTS 4.7.9. Each safety-related snubber shall be demonstrated OPERABLE by performance of the following augmented inservice inspection program and the requirements of Specification 4.0.5.

n t,;

a. Insoection Groups The snubbers may be categorized into two major groups based on whether the snubbers are accessible or inaccessible during reactor operation.

These major groups may be further subdivided into subgroups based on desiga, environment, or other features which may be expected to affect the OPERABILITY of the snubbers withih the subgroup. Each subgroup %

[4p6fp] may be hfr$54t/d independently in accordance with 4.7.9.\through 4.7.9'.h. mMo c(

b. Visual Inspection Schedule and Lot Size '

e )f (st d ervi visujiinspfdion oys'nubbpd sha 'becompdtedby[

Oct6ber 1, 19a , and, shall ptlude #1 snubbers o afety-refated s

] than wo snubbets areg6und intfperabj duringy tfie first/yst' ens. '

[in) vice isua nspe montb!cMon, 1 25%, Mom thytry/ dseconVinserv inspectipo shall ate gf)the fir,st<e visua)inspectjfin or d g

l he cutage an perJormed) pr su ffjdent du d' tion4t lea 2 hour2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br />,s/inMode))' Otherdise,

/s'sequpt visp1 inspe 1ons 11 be rformed 'n accord ece with jt,ne /

f ollpving sc 4dule: ) ,/ / /

og ut.m eao at^ M E v , re , ~ sa r- A N

June 20, 1985 SEQUOYAH - UNIT 1 3/4 7-21 Amendment No. 39

l I

I INSERT A All of the safety-related snubbers shall be included in one population or they i shall be categorized as accessible or inaccessible for visual inspection. If 1, used, the accessible or inaccessible categories shall be considered separately I

for visual inspections.

k' hen recombining categories into one population. the shorter interval of the categories shall be used.

The visual inspection interval for.the population or each category shall be determined based upon the criteria provided in Table 4.7.9-1, and the first inspection interval determined using this criteria shall be based upon the previous inspection interval a.s established by the requirements in effeet before amendment (*). .

?

1 l

4

• NRC will include the number of the license amendment that implements this change.

l l

.- ,..m-.-,,,,._.... . , , . . . . - . - _._ , _ . . _ . _ - - _ . . _ . _ , . . _ . . _ _ _ , _ _ _ . _ . . . _ . , . , _ _ - , . . , , . -

_. . -. _ . _ _ . _ _ _ - _ ___- _ _- - -- -__ -. - -. _ _ - ~ - - - . . - _ - - _ . - -__

pt. ANT SYSTEMS ",v"u" u ,~"ar u D.

L SURVEILLANC: REQUIREMENTS (Continued) l is I tior edu and Lo) ze (C .tinued)

Sn umb of In erable ers p*

SuF' sequent Vj,ual g j/'

lif's pec ti Perio# nspection /eriod*#

/ '

18 monp/ s i 25%

1 / / 12 mytths t 25%f

/ 2 / 6,tonths 1 25%

124 days i JE'%

3/ 4 /

, 6, 7 / s V25% j 8ormop p 62 day / 25%

31 day 7 j/

c. Visual Inspection Performance and Evaluation Visual inspections shall verify (1) that there are no visible indications of damage or impaired OPERABILTY, (2) bolts attaching the snubber to the foundation or supporting structure are secure, and (3) snubbers attached to sections of safety related systems that have experienced unexpected potentially damaging transients since the last inspection period shall be evaluated for the possibility of concealed damage and functionally tested, L,,

if applicable, to confirm operability. 7 Snubbers which appear inoperable as a result of visual inspections may be determined OPERABLE for the purpose of establishing the next visual inspection interval, providing that (1) the c'ause of the rejection is clearly established and remedied for that particular snubber and for other snubbers that may be genet . ally susceptible; and (2) the affected snubber is functionally tested, if applicable, in the as-found condition and determined OPERABLE per Specification 4.7.9.e. Hyoraulic snubbers with inoperable single or common fluid reservoirs which have uncovered fluid ports shall be declared inoperable. When hydraulic snubbers wticn have uncovered f'iuid ports are tested, the tests shall be performed by starting with the piston at the as-found setting and extending t'. pisten rod in the ex ension mode' direction, l

l Also, snubbers which have been made inoperable as the result of unespected j transients, isolated damage or other such random events, wtma the provisions et 4.7.9.g and 4.7.9.h have been met and any other appropriate corrective action implemented, shall not be counted in determining the next visual inspection interval.

I

d. Functional Test Schedule, Lot Size, and Composition During each refueling outage, a representative sample of 10% of the total of the safety-related snubbers in use in the plant shall be functionally tested either in place or in a bench test

• The inspection interval shall not be lengthened more than one step at a time

1. The provisions of Specification 4.0.2 are not applicable.

SEQUOYAH - !! NIT 1 3/4 7-22 Amendment No. 12 MAK20n82

, ,.m, m

TABLE yl. 7 9 4 l

$NUBBER V!$UAL INSFECTION INTERYAL 1 l t

_ NUMBER Or UNACCEPTABLE 5NUBBERS E topulation _ Column A Column 6 Column C or Category Extend Interval Repeat Interval Reduce Interval -

(Notes 1 and 2) (Notes 3 and 6) (Notes 4 and 6) (Notes 5 and 6) 1 0 0 1 80 0 0 2 100 0  ! 1 4 t

150 0 3 8 200 . 2 5 13 4

300 5 12 25 400 8 18 36 500 12 24 48 750 20 40 78 1000 or greater 29 56 109 Note 1: The next visual inspection interval for a snubber population or cate-pory size shall be determined based soon the previous inspection interval and the number of unacceptable snubbers found during that '

interval. Snubbers may be categorized, based upon their accessibility during power operation, as accessible or inaccessible. These categor-1es may be examined separately or jointly. However, the licensee , ,

must make and document that decision before any inspection and shall use that decision as the basis upon which to determine the next inspection interval for that category.

Note 2: Interpolation between population or category sizes and the numbe of unacceptable snubbers is permissible. Use next lower integer for the value of the limit for Columns A, B, or C if that integer includes a fractional value of unacceptable snubbers as determined by inter-poiation, i

Note 3: If the number of unacceptable snubbers is equal to or less than the number in Column A, the next inspection interval may be twice the

{ previous interval but not greater than 48 months, ,

I Note 4: If the number of unacceptable snubbers is equal to or less than the number in Column B but greater that the number in Column A. the next inspection interval shall be the same as the previous interval.

Note 5: If the number of unacceptable snubbers is equal to or greater than the numter in Column C, the next inspection interval shall be two-thircs of the previous interval. However, if the number of unacceptable snubbers is less than the number in Column C but greater than the number in Column _8, the next interval shall be recuced proportionally by interpolation, that is, the previous interval shall be reduced by a factor that is one-third of the ratio of the difference between the number of unacceptable snubbers found during the previous interval and the number in Column 8 to the differencu in the numbers in Columns B and C.

I Note 6: The provisions of Specification 4.0.2 are applicable for all inspec-tion intervals up to and including'40 months.

1 I

...---.,._----,-.-.--_._,..m._. ..,__ _ _..._ _ _-_... - _ . _ m _-. - . . -

4 1

1 PLANT SYSTEMS SURVEILLANCE REQUIREMENTS (Continued)

d. Functional Test Schedule, L ot Sire, and Composit ten (Continued)

The representative sample selected for f unctional testing shall include the various configurations, operating environments, and the range of site and capacity of snubbers within the groups or subgroups. The representative sample should be weighted to incluoe more snubbers from severe service 4

areas such as near heavy equipment. Unless a failure analysis as required l l

by 4.7.9.f indicates otherwise, the sample shall be a composite based on the ratio of each group to the total number of snubbers installed in the plant, $nubbers placed in the same location as snubbers which failed the previous functional test shall be included in the next test lot If the failure analysis shows that failure was due to location.

The security of fasteners for attachment of the snubbers to the component and to the snubber anchorage shall be verified on snubbers selected for functional tests.

e. Functional Test Acceptance Criteria lhe snubber functional test shall verify that; Activation (restraining action) is achieved within the specif ied

, L,.gs 1. ' k l iS

' ' range in both tension and compression, except that inertia dependent, acceleration limiting mechanical snubbers, may be tested to verify only that activation takes place in both directions of travel.

2. Snubber bleed, or release where required, is present in both tension and compression, within the specified range.

3. The force required to initiate or maintain motion of the (nubber is within the specif.ied range in both directions of travel.[/Als . , 6e t te l i cr as inAheforce/reairesh 1 tv t e St urv Ila .ce ee;f60ttat t 'rtnub nt -

pfttrC mo nt req /1re$jatpheIst ast ,5 p ung>. /per/

prfvi,4ed,ghatjheJarceregire i is it /

4. For snubbers specifically required not to displace under cont inuous load, the ability of the snubber to withstand load without displace-ment shall be verified.

S. Testing methods may Le used to measure parameters indirectly or parameters other than those specified if those results can be correlated to the specified parameters through established methods

f. Functional Test failure Analysis and Additional Test Lots up or if any snubber selected for functional testing either fails to lock fails to move due to manufacture or design deficiency, all snubbers of the same design subject to the same defect shall be functionally tested M4di 25198P f

3/4 7-23 Amendment No. !?

i SEQUOYAH - UNIT 3 l

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_ _ _ . _ . _ _ _ . . - . _ _ _ _ _ _ _ . _ _ _ _ _ _ __ _ . _ ~. _ _ _ _ _

PLANT SYSTEMS BASES

(

SNUBBERS (Continued) that may be generically susceptible and operability verified by inservice func-tional testing, if applicable, that snubber may be exempted from being counted as inoperable. Generically susceptible stubbers are those which are of a specific make or model and have the same design features directly related to rejection of the snubber, or are similarly located or exposed to the same

. environmental conditions such as tempe_rature, radiation, and vibration.

Tror Unifie(tM groups may be established based on design features and installed conditions which may be expected to be generic. Each of thesel N Wtn ittA#g groups are M@@AeroNT tested separately unless an engineering analysis indicates the Do Ui(n group is improperly constituted._ All suspect snub-bers are subj to in'spection and testing regardless of[f # e M M groupings.

Mhn.- ~mr To further increase the assurance of snubber reliability, functional tests shall be performed during each refueling outage. These tests will include stroking of the snubbers to verify proper movement, activation, and bleed or release. The performance of hydraulic snubbers generally depends on a clean, deaerated fluid contained within variable pressu e ;hambers, flowing at closely controlled rates. Since these characteristics are subject to change with expo-sure to the reactor environment, time, and other factors, their performance within the specified range should be verified. Mechanical snubbers which depend upon overcoming the inertia of a mass and the braking action of a capstan spring contained within the snubber for limiting the acceleration of the attached compo- (". . . ., ,

nent (within the load rating of the snubber) are not subject to changes in per- -

formance in the same manner as hydraulic snubbers. Pending the development of information regarding the change during the service of the snubber of the acceleration / resistance relationship and the optimum method for detecting this change, these mechanical snubbers may be tested to verify that when subjected to a large change in velocity the resistance to movement increases greatly.

The performance change information 5-t,o-be-developed in order to establish test methods to be used during and af ter the first refueling outage.

v r u n r<

Ten percent of the total popu tion of j(pfM)Vtglf /p(d snubbers is an adequate sample for functional tests. The initial sample is to be proportioned among the groups in order to obtain a re;m.entative sample. Observed failures of more than two snubbers in the initial ;ot will require an engineering analysis and testing of additional snubbers selected from snubbers likely to have the same defect. A thorough inspection of the snubber threaded attach-ments to the pioe or components and the anchorage will be made in conjunction t

with all required functional tests.

A list of individual snubbers with detailed information of snubber loca-t tion and size shall be available at the plant in accordance with Section 50.7Hc) of in CFR_p u t_5% The_attuffb d ourt Vapd.cde/byd.he/ Pigd prier 4do/_il_ilg_pl och snupber shall be determined .c E'3 \Rg based upon the existing radiation levels and U$e expected time to perf orm a visual inspection in each snubber location as well as other factors associated with accessibility during plant operations (e.g. , temperature, atmosphere.

June 20 1985 SEQUOYAH - UNIT 1 B 3/4 7-6 Amendment No. 39 f .

~

l PtANT SYSTEMS 3/4.7.9 SNUBBERS LIMITING CONDITION FOR OPERATION H

3.7.9 All safety-relah*d snubbers shall be OPERABLE.

APPLICABILITY: MODES 1, 2, 3 and 4 (MODES S and 6 for snubbers located on systems or partial systems required OPERABLE in those MODES.)

ACTION:

With one or more snubbers inoperable, within 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> replace or restore the inoperable snubber (s) to OPERABLE status and perform an engineering evaluation on the attached component or declare the attached system inoperable and follow the appropriate ACTION statement for that system.

SURVEILLANCE REQUIREMENTS 4.7.9 Each safety-related snubber shall be demonstrated OPERABLE by y,._.:

"""" performance of the following augmented inservice inspection program and the requirements of Specification 4.0.5. R31

a. Inspection Groups The snubbers may be categorized into two major groups based on whether the snubbers are accessible or inaccessible during reactor operation. These major groups may be further subdivided into subgroups based on design, environment, or other features which may be expected to affect the OPERABILITY of the snubbers within the subgroup. Each subgrouplgrfgrgt$1 may be l}fispepfe/lindependently in accordance with 4.7.9. through 4.7.9.h. 7 5 > '~4 u

~

b. Visual Insoection Schedule J[e rst nse bu vice vis il in ectiott of s- bbers shall io rn' ar

• faft r 4 ont wi of c -menci-a shp 1 i clu al inIpmont[t snu ers P0c! Di'L P ,10'4 safe -rela d sy ' ems, f it

, an/woh) bbg s ar, foung inopey ble ring e fi; t ine rvy e l ptrLarc Aap MM" wm H sma r- i9 June 20,1985 SEQUOYAH - UNIT 2 3/4 7-21 Amendment No. 31

PLANT SYST[M5 pa ut ni envv b A <x ~

p , r ,4 ja g 4,g r f} l SURVfillANCE REQlllRfMENTS (Continued) g )

/b V}[al pedIon dul[ Cont'g)! [ /

v nsp i econAdriservi visual .s shall V

+ 25%from the gate of tM,.ifirst eJtipection(

ae r,fo 'med mont p",

0+Nerwiye,)subt. quent ynual inp+,ctions Wall be fi petformed Acopf5nceyifhthe)<Illowingdichedule ,/ j/

5 p n te Subse, t Vipt I) pts mp g6AAtx /

Pef od

/ / [ /

In<cect ion f/riod*#[

/ 125%/

/

m.rs /~s,wr /

0,f 18 morphs g ,/ 12,pcnth5 2A $%

,/

/ 2 3,4 /

/ ' J month & 25% /p,- )

24 dayC 1 25% /  ;

5 <7 62, days 1 ?,% ,/

j6)ormor3 i

,/ ,)2 daysp/25% j .

c. Visual Inspection Performance and Evaluation Visual inspections shall verify (1) that there are no visible M indications of damage or impaired OPERABILITY, (2) bolts attaching fy e the snubber to the foundation or supporting structure are secure, and (3) snubbers attached to sections of safety-related systems that have experienced unexpected potentially damaging transients since the last inspection period shall be evaluated for the possibility of concealed damage and functio,nally tested, if applicable, to confirm operability.

Snubbers which appear inoperable as a result of visual inspections may be determined OPERABLE for the purpose of establishing the next visual inspection interval, providing that (1) the cause of the rejection is clearly established and remedied for that particular snubber and for other snubbers that may be generically susceptible; and (2) the affected snubber is functionally tested, if applicable, in the as-found condition and determined OPERABLE per Specifica-tion 4.7.9.e. Hydraulic snubbers with inoperable single or common fluid reservoirs which have uncovered fluid ports shall be declared inoperable. When hydraulic snubbers which have uncovered fluid ports are tested, the tests shall be performed by starting with the piston at the as-found setting and extending the piston rod in the extension mode direction.

'The inspection interval shall not be lengthened more than one step at a time. , g The provisions of Specification 4.0.2 are not applicable.

Amendment 2 SEQUDYAH - UNIT 2 3/4 7-22 9/33/81 1

1 l

a INSERT A

All of the safety-related snubbers shall be included in one population or they shall be categorized as accessible or inaccessible for visual inspection. If i used, the accessible or inaccessible categories shall be considered separately for visual inspections.

When recombining categories into one population, the shorter interval of the categories shall be used.

The visual inspection interval for the population or each category shall be determined based upon the criteria provided in Table 4.7.9-1, and the first inspection interval determined using this cri +

• shall be based upon the l previous inspection interval as established b, tre requirements in effect before amendment (*). ,

I i

1 i

l l

{

i

• NRC will include the number of the license amen: ment that implements this j

change.

, ,,%<-em-,-.,--.r,w-m-w-r,-- .r,w.w- y,w ,= w re, e ,w,--, --ww,.g m e r~w---r-t

TABU M Z 7'/

$NUBBER Vl$UAL INSPECT 10H INTLRYAL NUMBER Of UNACCEPTABLE SNUBBERS Population Column A Column I Cilumn C or Category Extend Interval Repeat Interval Reduce Interval (Notes 1 and 2) _(Notes 3 and 6) (Notes 4 and 6) (Notes 5 and 6) 1 0 0 1

,80 0 0 2 100 0 1 4 150 0 3 8 200 . 2 5 13 300 5 12 25 400 8 18 36 500 12 24 48 750 20 40 7F 1000 or greater 29 ,

56 109 Note 1: The 9 ext visual inspection interval for a snubber pcpulation or cate-gory si:e shall be determined based upon the previous inspection Interval and the number of unacceptable snubbers found during that interval. Snubbers may be categorized, based upon their accessibility during power operation, as accessible or inaccessible. These categor-its may be examined separately or jointly. However, the licensee ,

must mate and document that decision before any inspection and shall use that decision as the basis upon which to detemine the next inspection interval for that category.

Note 2: Interpolation between population or category si:es and the number of unacceptable snubbers is permissible. Use next lower integer for the value of the limit for Columns A, B, or C if that integer includes a fractional value of unacceptable snubbers as determined by inter.

palation.

Note 3: lf the number of unacceptable snubbers is equal to or less than the number in Column A, the next inspecticn interval may be talce the previcus interval but not greater than 48 months.

l late 4: If the number of unacceptable snubbers is equal to or les . t han the number in Column B but creater that the number in Colum A. the wxt inspection interval shall be the same as the previour, ink rv al .

Pcte 5: If the number of unacceptJble snubbers is equal to or greater than the numter in Column C, the next inspect 1on interval shall be two-thirds of the previous interval. However, i f the number of unacceptable snubters is less than the number in Column C but greater than the number in Column B, the next interval shall be recuted proportionally by interpolation, that is, the previous interval shall be reduced by 4 f actor that is one-third of the ra tio of the di f f erence between the number of unacceptable snubbers found during the previous interval and the number in Column B to the dif ference in the numbers in Columns B and C.

Note 6: The provis1ons of Specification 4.0.2 are applicable for all inspec-tion intervals up to and including 48 months.

l l

ptANT SYSTEMS l

SURVEILLANCE REQUIREM[NTS (Continued) c, Visual Inspection performance and Evaluation (Cont'd)

Also, snubbers which have been made inoperable es the result of unexpected transients, isolated damage or other such random events, when the provisions of 4.7.9.g and 4.7.9.h have been met and any other appropriate corrective action implemented, shall not be counted in determining the next visual inspection interval.

d. Functional Test Schedule, tot Size, and Composition During each refueling outage, a representative sample of 10% of the total of the saf ety related snubbers in use in the plant shall be R2 functionally tested either in place or in a bench test.

The representative sample selected 'or f unctional testing shall include the various configurations, operating environments, and the range of size and capacity of snubbers within the groups or subgroups.

The representative sample should be weighted to include more snubbers from severe service areas such as near heavy equipment. Unless a failure analysis as required by 4.7,9.f indicates otherwise, the sample shall be a composite based on the ratio of each group to the total number of snubbers installed in the plant. Snubbers placed in 4

the same location as snubbers which failed the previous functional f:7.*:2 test shall be included in the next test lot if the failern analysis shows that failure was due to location.

The security of fasteners for attachment of the snubbers to the component and to the snubber anchorage shall be verified on snubbers selected for functional tests.

e. Functional Test Acceptance Criteria The snubber t'unctional test shall verify that:

1. Activation (restraining action) is achieved within the specified range in both tension and compression, except that inertia dependent, acceleration limiting mechanical snubbers, may be tested to verify only that activation takes place in both directions of travel.

2. Snubber bleed, or release where required, is present in both tension and compression, within the specified range.

3. The force required to initieta or maintain motion of the snubber is within the specified range in Loth directions of travel.

@lp6, J41e hJ cr/ase/in tfe foyte r/quifed </iall not exceed l pav TE SEQUOYAH - UNIT 2 3/4 7-23 ^*"" *""'

9/lb 31

l

,bp' PLANT SY51LMS SURVEILL ANCE REQUIREMENTS _(Continued)

e. functional Test Acceptance Criteria (Cont'd) 0 c to[heauntrqui at th ast veilla e te [

pg o thp snybber, p ovid that the fo ereg4[redisA le ..

5 p6und,s / / / /

4. For snubbers specifically required not to displace under continuous load, the ability of the snubber to withstand load without displacement shall be verified.

5. Testing rnethods may be used to measure parameters indirectly or parameters other than those specified if those results can be correlated to the specified parameters through established methods,

f. Functional Test failure Analysis and Additional Test Lots If any snubber selected for functional testing either fails to lock up or failc to move due to manufacture or design deficiency, all snubbers of the same design subject to the same defect shall be 4 functionally tested.

If more than two snubbers do not meet the functional test acceptance criteria, an additional lot equal to one-half the original lot size shall be functionally tested for each failed snubber in excess of the two allowed failures. An engineering evaluation sh611 be made of each failure to meet the functional test acceptance criteria to determine the cause of the failure. The result of this analysis shall be used, if applicable, in selecting snubbers to be tested in the subsequent lot in an effort to determine the operability of other snubbers which may be subject to the same failure mode.

(Selection of snubbers for future testing may also be based on the failure analysis.) Testing shall continue until not more than one additional inoperable snubber is fnund within a subsequent required lot, or all snubbers of the original inspection group have been tested, or all suspect snubbers identified by the failure analysis have been tested, as applicable. ~

(d I L L.

The discovery of loose or missiag attachment fasteners will be evaluated to determine whether the cause may be localized or generic.

The result of the evaluatior k be used to select other suspect snubbers for verifying the attachment fasteners, as applicable.

Wubbers shall not be subjected ta prior maintenance specifically for the purpose of meeting functional test requirements.

Amendment ?

SEQUOYAH - UNIT 2 3/4 7-24 9/1s/81

k' pt ANI SYST[MS 1

4 BASES 3/4.7.9 SNUBBERS (cont'd)

When the cause of the rejection of a snubber in a visual inspection is clearly established and remedied for that snubber and for any other snubbers that may be generically susceptible and operability verified by inservice functional testing, if applicable, that snubber may be exempted from being counted as inoperable. Generically susceptible snubbers are those which are of a specifit make or model and have the same design features directly related to rejection of the snubber, or are similarly located or exposed to the_same envirnnmental /T3sr conditions such as temperature, radiation, and vibration. Ifnfppttfr/y groups ~

may be established based on design f eatures and installed coriditions which may be expected to be generic. Each of these (gs)(epig groups areyff Acfe/j/arkfl- WM testedseparatelyunlessanengineeringan[alys1 11ndicates the hf / ectiNI group is improperly constttuted. All suspect ,nubbers are subject to inspection and testing regardicss of M.#cylpfy; groupings. v e " "t T V .*. T

To further increase the assurance of snubber reliability, functional tests shall be performed during each refueling outage. These tests will inclLde stroking of the snubbers to verify proper movement, activation, and bleed or release. The performance of hydraulic snubbers generally depends on a clean, g deaerated fluid contained within variable pressure chambers, flowing at closely ~g~

controlled rates. Since these characteristics are subject to change with , ,,

exposure to the reactor environment, time, and other factors, their performance within the specified range should be verified, Mechanical snubbers which depend upon overcoming the inertia of a mass and the braking action of a capstan spring contained within the snubber for limiting the acceleration of n the attached component (within the load rating of the snubber) are not subject to changes in perf ormance in the same manner as hydraulic snubbers. Pending the development of information regarding the change during the service of the snubber of the acceleration / resistance relationship and the optimum method for detecting this change, these mechanical snubbers may be tested to verify that when subjected to a large change in velocity the resistance to movement increases greatly. The perf ormance change information i4re-+e developed in order to establish test methods to be used during and after the first refueling

" 390- pg 1 9 Ten percent of the total population of[p'goxjtnat41vd2dj snobbers is an adequate sample for functional tests. The initial sample is to be proportioned among the groups in order to obtain a representative sample. Observed failures of more than two snubbers in the initial lot will require an engineering analysis and testing of additional snubbers selected from snubbers likely to have the same defect. A thorough inspection of the snubber threaded attachments to the pipe or components and the anchorage will be made in conjunction with all required functional tests, Amendment 2 SEQUOYAH - UNIT 2 B 3/4 7-6 9f i 3f m

BASES 3/t.7 9 SNUB 8ERS (cont'd) l A list of individual snubbers with detailed information of snubber location and size shall be available at the plant in accordance with Section 50.71.(c) of 10 CFR Part 50. The accessibility of each snubber shall be determinedphnp' /

S2Lts.M -

La'parovpd by/t t>6 Pl/nt Operat,(ons Aeview Cgmmityee. /The (eterpina, lion /sliF11/be/ R31

~ based upon the existing radiation levels'and the eipected time to perfofm a visual inspection in each snubber location as well as other factors associated with accessibility during plant operations (e.g. , temperature, atmosphere, location etc.), and the recommendations of Regulatory Guide 8.8 and 8.10. The addition or deletion of any hydraulic or mechanical snubber shall be made in accordance with Section 50.59 of 10 CFR Part 50.

3/4.7.10 SEALED SOURCE CONTAMINATION The limitations on removable contamination for sources requiring leak testing, including alpha emitters, based on 10 CFR 70.39(c) limits for plutonium. This limitation will ensure that leakage from byproduct, source, and special nuclear material sources will not exceed allowable intate values.

Sealed sources are classified into three groups according to their use, with

' surveillance requirements commensurate with the probability of damage to a source in that group. Those sources which are frequently handled are required to be tested more often than those which are not. Scaled sources which are

(_, continuously enclosed within a shielded mechanism (i.e., sealed sources within radiation monitoring or baron measuring devices) are considered to be stored and need not be tested unless they are removed from the shielded mechanism.

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l i June 20, 1985 SEQUOYAH - UNIT 2 8 3/4 7-Ga Amendment No.31 l

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I l ENCLOSURE 2 PROPOSED TECHNICAL SPECIFICATION CHANGE i

SEQUOYAH NUCLEAR PLANT UNITS 1 AND 2 DOCKET NOS. 50-327 AND 50-328 (WA-SQN-TS-91-06 )

DESCRIPTION AND JUSTIE! CATION FOR REVISIONS TO TECHNICAL SPECIFICATION 3/4.7.9 - SNUBBERS l

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i Descript ip!Lpf_ Cha!c TVA proposes to modify the Sequoyah Nucleat Plant (SQN) Units 1 and 2 Technical Specifications (TSs) pertaining to the safety-related snubber inspection and testing program as described in TS 3/4.7.9.

Generic Letter (GL) 90-09, " Alternative Requirements f or Snubber Visual i Inspection Intervals and Corrective Actions." provides guidance to revise Surveillance Requirement (SR) 4.7.9 and the associated bases pertaining to the visual inspection schedule. This guidance consists of replacing the i j TS frequency table with an altirnate table including the associated notes. The new table will provide f or an extension or reduction of the ,

inspection interval based upon previous inspection results.

1 SR 4.7.9.a has been revised to reflect the difference in the functional j testing and visual inspection programs that is required by this r

implementation of GL 90-09. This change is also reflected in the bar.ei.

section.

SR 4.7.9.e.3 has been revised to eliminate the 50 percent increase in drag force statement.

In the bases section of TS 3/4.7.9, the Plant Operation Review Committee ,

(pORC) is denoted as determining and approving the addition and deletion of snubbers to the accessible or inaccessible list. TVA is proposing to delete this reference.

I The wording "approximately 700" has been deleted from the third paragraph ,

of the bases section, page 11 3/4 7-6 for both units. In addition, a tense r change has been made in the last sentence of the second paragraph on this same page to reflect that SQN is now past the first refueling outage, page 3/4 7-24 of t he t'n i t 2 TS has a typographical error corrected (vil to will).

Reason for_ Change As discussed in GL 90-09 it has been recognized that the current snubber

visual inspection schedule imposes significant resource requirements

• throughout the indurtry. These resource expenditures for visual inspection provide little added assurance of snubber operability above that provided by the required functional t e s t i ng, . For this reason, NRC has proposed a change in the schedule for performing visual inspections.

TVA concurs with the results of GL 90-09.

With the issuance of GL 90-09, it became apparent that the functional testing and the visual inspection programs had different requirements for breaking dows. the population of snubbers. Visual inspections are relevant i to the total p pulation or are broken down into either accessible or inaccessible. No further breakdown is allowed for visual inspection.

Functional ten'ing grouping is based upon design, environmsnt, or other features that may be expected to affect the operability of the snubber.

This required SQN to change SR 4.7.9.a to define the differences.

ER 4.7.9 e.3 requires that the force required to initiate or maintain motion of the snubber is within the specifled range in both directions of

. l travel. This functional test is performed to determine if the snubber is capable of performing its intended design function. SR 4.7.9.c.3 f urther states that the increase in the drag force shall not exceed 50 percent of the amount at the last surveillance test. However, this criterion is not for the purpose of ascertaining if the snubber is operable, but to i determine if a trend exists that is indicative of pending snubber failure, in accordance with the bases section of TS 4.0.1, the SR is intended to determine operability for the subject system, thus the second

, sentence of SR 4.7.9.e.3 has been proposed to be deleted. This deletion is consistent with NRC observations identified in Inspection Report No. 50-327,328/86-67.

The PORC review of changes to the accessible or inaccessible listing per the bases section of TS 3/4.7.9 is an unnecessary and outdated requirement. Since the initial development of these TS bases, SQN has implemented a Qualified Reviewer (QR) Program per TS 6.5.l A. Changes in procedures governing the accessibility of snubbers are reviewed through the QR process.

i SQN is proposing to remove the wording "approximately 700" itom the bases section since this number is no longer valid. Through various modifications to each unit, the number has changed.

Justification for Change The functional tests provide an acceptable confidence level that the safety-related snubbers will be operable. The visual inspection is a separate process that was developed to complement the functional testing

! program and to increase the confidence level of snubber operability.

Based upon the Brookhaven National laboratory report reviewed by NRC very 7

few snubbers were found inoperable because_of the visual inspection; and accordingly, NkC justified a revised schedule for visual inspections. As GL 90-09 indicates, several utilities, including SQN, have spent a signif icant amount of resources performing visual inspections. Also, i plant persennel have been subjected to additional radiological exposure to comply with the required inspections. By substituting the new visual inspection schedule, SQN will be reducing future occupational radiation exposure, implementation of this new schedule is ennsistent with NkC's policy statement on TS improvements.

The placement of the "50 percent increase in the drag force" statement in SR 4.7.9.m.3 is inappropriate as it does not identif y inoperable snubbere,,

but rather may be indicative of an adverse trend. The drag force increase of greater than 50 percent is addressed in SR 4.7.9.1 that requires the

-life of mechanical snubbers to be monitored. Mechanical snubbers may have a-greater than 50 percent increase in drag force and still remain within

- the design limits. This trend for mechanical snubbers is addressed in i SR 4.7.9.i where the approach to "end of service life" is required to be tabulated and reviewed. As a note of clarification, hydraulic snubbers are not included since they traditionally f ail f rom fluid leakage that

! decreases the drag force. Thus, elimination of the second sentence in l SR 4.7.9.e.3 removes potential confusion in applying the SR while SR

! 4.7.9.1 maintains the surveillance trending.

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J SQN is proposing to remove reference to PORC from the approval process when a snubber is added or deleted to the accessible or inaccessible list for visual inspections. TS 6.5.1A describes SQN's QR Program, which has been added since the requirement for PORC approval. By subjecting the snubber procedures to be reviewed by qualified personnel, the minor changes required from future modifications and procedure changen. will be

! reviewed in sufficient detail. This is a bases change only.

The removal of "approximately 700" from the bases does not change the l program desertption. As a result of the removal of the upper head injection system, resistance thermal detector bypass piping, and various other plant modifications, the snubber population has decreased to approximately 500. Replacement of the "700" with another number would be of little benefit since it will continue to change as SQN implements other system modifications. This is also a bases change only.

Environmental Impact Evaluation i

The proposed change request does not involve an unreviewed environmental question because operation of SQN Units 1 and 2 in accordance with this

-change would not:

1. Result in a significant increase in any adverse environmental irrpact j previously evaluated in the Final E.nvironmental Statement (FES) as modified by the staff's testimony to the Atomic Safety and Licensing Board, supplements to the FES, environmental impact apprair.als. or decisions of the Atomic Safety and Licensing Board.

2. Result in a significant change in effluent or power levels.

3. Result in matters not previously reviewed in the licensing basis for SQN that may have a significant environmental impact.

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! l i ENCLOSURE 3

! PROPOSED TECilNICAL SPECIFICATION CilANCE  !

l L SEQUOYAll NUCLEAR PLANT UNITS 1 AND 2 i

DOCKET NOS. $0-327 AND 50-328 l l-I ,

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l DETERMINATION OF NO SIGNIFICANT liA2ARDS CONSIDERATION l

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Significant Harards Evaluation TVA has evaluated the proposed technical specification (TS) changes and has determined that they do not represent a significant harards ,

consideration based on criteria established in 10 CFR 50.92(c). Operation of Sequoyah Nuclear plant (SQN) in accordance with the proposed amendment will not:

1. Involve a significant increase in the probability or consequences of an accident previously evaluated. I l

The proposed wording changes to SR 4.7.9.a resulted from a need for clearer definition of the snubber visual and f unctional testing program. The proposed change to SR 4.7.9.e.3 does not involve a significant increase in the probability or consequences of an accident previously evaluated. This SR addresses the operability of a snubber. During the functional test, the mechanical snubber may display an increase of 50 percent or more in drag force and still remain within its design limits. This increase in drag force for mechanical snubbers displays a trend. This trending is addressed in SR 4.7.9.1 where the approach to "end of service lite" is required to be tabulated and reviewed.

The proposed schedule for visual laspection of snubbers was developed l by NRC and published in Gener-ic Letter (GL) 90-09, " Alternative Requirements For Snubber Visual Inspection Intervals and Corrective J Actions." The operability of snubbers is predominately determined by functional testing for which SQN has an approved program. Based upon the Brockhaven National Lebc.atory report reviewed by NRC, very few '

snubbers were found inoperable because of the visual inspection; and accordingly, NRC justified a revised schedule for visual inspections.

Since the testing program and inspection r.till provide the appropriate confidence level of operability, there is no significant increase in the probability or consequences of an accident previously analyzed.

2. Create tp pos: .bility ot a new or different kind of accident from any previous vi analyzed.

e Based upon"GL 90-09, NKC has addressed these proposed changes to the visual inspection program, and the confidence level for operability retrains the same. Additionally, the other changes in the SRs do not affect operability. These changes do not alter any plant operations, maintenance requirements, or system design or tunctions. Therefore, no new or different accidents are created from the proposed change.

3. Involve a significant reduction in a margin of safety.

The proposed change in the visual inspection program f or snubbers does not make modifications to the plant or revise its mode of operation on the present safety analysis. As previously described with the proposed changes to the SRs, the confidence level for snubber operability remains the same; therefore, there is no significant reduction in any safety margin.