ML20235Z581
| ML20235Z581 | |
| Person / Time | |
|---|---|
| Site: | Rancho Seco |
| Issue date: | 08/31/1987 |
| From: | Gough E, Sandra Talley, Vinquist J SACRAMENTO MUNICIPAL UTILITY DISTRICT |
| To: | |
| Shared Package | |
| ML20235Z573 | List: |
| References | |
| GCA-87-532, PROC-870831, NUDOCS 8710210208 | |
| Download: ML20235Z581 (83) | |
Text
- _ - - . .-__- _.
$W -,: ,
0' '
.y Enclosure y To GCA 87-5321
.i' b
- WIRE AND CABLE PROGRAM REPORT RANCHO SECO NUCLEAR GENERATING STATION
- l. SACRAMENTO MUNICIPA'L UTILITY DISTRICT 4
l SACRAMENTO 1.
REVISION 2 AUGUST-31, 1987 PREPARED BY: APPROVED:
U Wb' CRTS PROGRAM C00RDINpTOR - f MANAGER OF QUAUTY DEPARTMENT a -- S. R. Talley J. V. Vinquist -l 4 WLkp hg !
CRTS PROGRAM MANAGER MAffAGER OF NUCLEAR ENGINEERING E. J.-Gough G. V. Cranston j l
8710210208 873012 ~I ~
PDR ADOCK 05000312 I P ppg j k ;
L= .
--- -_ - _- A
i i
. Enclosure To GCA 87-532 l-WIRE AND CABLE PROGRAM REPORT ;
- 1. _ INTRODUCTION The-Rancho Seco Nuclear Generating Station at plant turnover in 1975 had a j cable population of about 14,000 cables installed mostly in ladder type cable tray and in steel conduit. Since 1975 about 9,000 cables have been added while a few have been deleted.
In common with all large modern power plants in the United States, Rancho Seco tracks its raceway and cable data in a computerized program run on a main frt.me computer. The current program has an acronym of CRTS (Cable Raceway Tracking System) and performs some checks and calculations as well as recording and reporting data. CRTS has been in place since July of 1980.
The original cable population of 14,000 was installed by Bechtel Power Corporation (BPC). BPC was both designer and constructor. Until the CRTS program was put in place in 1980, the cable and raceway was tracked by a {
BPC Program EE-553. This program has been used for over 20 nuclear power plants.
- 2. BACKGROUND DISCUSSION 2.1 INITIATING EVENTS Although some questions concerning CRTS completeness, missing CRTS .
cards and conflicting procedures were raised by resident inspectors !
as early as 1983, major concerns did not arise until 1985 and 1986.
In 1985 questions arose concerning the degree of design control exercised following spurious actuations reported in LER 85-16. In 1
1986 questions arose concerning the degree of control exercised during the installation process and the valLity of "as-built" information in the CRTS data base following issuance of LER 86-10. .
Employee allegations regarding overfilled cable trays and incomplete !
data in CRTS, added to the level of concern.
The July Wire and Cable Program Report contained 56 CRTS Action Items, including entries for 16 NCR's and 12 ODR's. The August Wire and Cable Program Report has been reformatted and now lists ODR's and NCR's separately from the CRTS Action Item List [ Attachment (1)]. 4 CRTS Action Items 1 through 22 remain the same, Item 23 is now listed l under NCR S-5270 in the CRTS NCR List, Items 24 and 25 have been combined and are now Item 23. 0DR's and NCR's listed as items 26 through 52 are now listed by the appropriate ODR or NCR number in either the CRTS ODR List [ Attachment (2)] or the CRTS NCR List
[ Attachment (3)] as appropriate. CRTS Action Items 53 through 56 now !
appear as CRTS- Action Items 24 through 27 respectively. An a additional item has been included, Item 28, which provides the bases j for acceptability of the 95/95 level of assurance regarding cable i 1
routing.
-2 -
Enclosure To GCA 87-FJ2 Identified problems are listed in the CRTS Action Item List
[ Attachment (1)] , the CRTS ODR List [ Attachment (2)], and the CRTS NCR List [ Attachment (3)], with appropriate references. The separate ODR and NCR lists have been expanded and now provide descriptions of the occurrences or nonconformances, direct causes, corrective actions and reference to the CRTS Action Item Commentaries [ Attachment (4)], !
where appropriate.
2.2 INITIAL ACTIONS Initial action taken by SMUD was to initiate enhancement of the CRTS l program in taid-1986 and to use the enhanced program to check for raceway overfills, violations of separation criteria, intermixing of instrument cables with power and control cable, and other discrepancies as listed in the Action Plan. Although a number of discrepancies were " bookkeeping" problems, generated by the ,
enhancement, a significant number could, potentially, have been of real concern. Identified discrepancies are documented in reports !
from the SMUD contractor [IMPELL] to SMUD and their dispositions {
described in Item 2 of the CRTS Action Item List and supported by 1 calculations in SMUD files. Late in 1986 a decision was made to j signal trace a significant sample of the approximately 2400 safety 1 cables installed from 1975 through 1986 and compare the "as-built" ;
condition with plant documents end the CRTS data base to establish a !
level of confidence in the reliability of the data base. The signal tracing has found sufficient number of major defects in both Lot 1 (400 cables) and Lot 4 (78 cables) to require 100% inspection of each i lot. In late June, 1987 sampling was complete in Lots 2, 3 and 4.
However, in July,1987 a decision was made to sample Lot 2 to the "one-defect" level, increasing the size of Lot 2 by 35 cables. In early September approximately 32 cables remain to be checked, with 590 cables complete. Simply stated, the intent was to establish 95 l percent confidence that the true percentage of discrepant circuits
[ major defects] in the sampled population is no greater than 5 percent. Inspection totals are in fact higher for lots 2 and 3 than are required to establish this confidence level. See commentary to CRTS Action Item 28. ;
Forecast completion is October 16, 1987. The current status is described in the commentary to CRTS Action Item 1 [ Attachment (4)].
2.3 ACTION PLAN SMUD has provided a document [ Appendix (2)] to the NRC which describes a five part Action Plan to consolidate the various activities of the Nuclear Engineering Department, which deal with the cable and raceway questions.
Although the scope of the plan is complete, the details and the .
individual actions require additional definition to enable a reviewer !
to easily determine the acceptability of the resolution of each item (i.e., question or issue raised). The Wire and Cable Program Report is intended to replace the Action Plan and to provide additional definition and schedule information on a monthly basis. 3
-3 -
Enclosure To GCA 87-532-WIRE AND CABLE' PROGRAM REPORT (Continued) 2.4' CRTS ACTION ITEM LIST AND COMMENTARY This report provides a listing of twenty-eight CRTS action items
[ Attachment (1)] with a detailed commentary on each [ Attachment (4)]. This list is intended to serve as a record of all questions raised and of all known problems, other than ODR's and NCR's. For-each item the list includes an item number, description, source, status and schedule 'for resolution, if appropriate.
A commentary will be provided on each item covering chronology..
generic implications, causes and corrective actions as appropriate.
The August report contains all commentaries, except those for items 15, 25, 26 and 27 which will be provided in the October Wire and Cable Program Report.
To understand the significance of each item it is necessary to read the attendant commentary. The major concerns are summarized in Section 3.
2.5 CRTS.Related ODR's and NCR's CRTS relsted ODR's and NCR's are now listed separately [ Attachments 2 and 3] with descriptions, causes, corrective actions and reference to the CRTS Action Item Commentaries, where appropriate.
- 3. MAJOR CONCERNS ISSUES C0!(O j[NS Procedures The level of control exercised on cable installation.
Sampling Plan Accuracy of CRTS data on cable locations.
Data Base Completeness Omission of cables from data base.
Raceway Fill Control of cable tray fill [ weight and ampacity questions].
Desien Control Mixing of instrument cables [with power &
control] in design process.
CRTS Discrepancies Control and entry of data into CRTS.
Records Control of documents of record.
Miscellaneous Problems Completeness of licensee action in resolving problems.
i Root Causes Identification and correction of all identified root causes.
-4 -
L - - - - - - - - - - - - -__----------_-----_---_______--d
- p. - p; -
.- ', f T d' t Enclosure 4
- To GCA 87-532
, ).
~
l .- WIRE AND CABLE PROGRAM REPORT (Continued)
Status' ofLeach issue is, in summary,.as follows:
3.1 PROCEDURES-Procedures'in place:during'the' original construction period ~ are.
I addressed in Item 7 of the CRTS Action Item List. Procedures in place from 1975 through 1986 will be' addressed by the Independent' Investigation / Reviews Group [IIRG] in closing ' Item 25 of. the CRTS -
Action Item List.
- 3.2 SAMPLING PLAN This issue is fully addressed in the commentary to Item 1 of the CRTS Action Item List.
s 3.3 DATA BASE COMPLETENESS The " completeness" issue of the CRTS data, centers on the data concerning the' telephone and security cables. This issue, although real, has no significant safety implications. The issue also
. includes questions' concerning the verification of CRTS software.-
' Items 10.11,12,13 and 14 of the CRTS Action Item List cover the
~
completeness issue.
-3.4 RACEWAY FILL The cable tray fill- and weight questions have been reviewed.
Percentage fill and weights for all cable trays have been checked.
' Although some relatively minor questions remain to be answered, no significant problems have been found. Changes are planned to USAR i
- which will reconcile- differences between the USAR and Nuclear
- - Engineering Procedures and will clarify design limits. Enhancements ;
planned to the CRTS software will, when in place, automatically prevent fill and weight limits-from being exceeded.
i These questions are addressed in Items 2 [ partial], 6 and ODR 86-125.
2.5. DESIGN CONTROL Thedesigncontrolissueisliorecomplexthantheracewayfillissue, f 1
but problems are limited to ( relatively small number of instrument cables which mix with power and control cables and violate design criteria. No evidence has besn found of a programmatic failure -I following a review of the or191nal 14,000 cable population. Checking of the 9000 cables added after commercial operation continues, but is ]
not expected to change this curent evaluation.
6 -
i f
l Enclosure-To GCA 87-532 WIRE AND CABLE PROGRAM REPORT (Continued) t The question of a 90ssible generic design problem in the original 14,000 cable population is addressed in Item 5 of the CRTS Action Item List. Other specific mix questions are addressed in Items 2
[ partial], 9 and by ODR 87-307 and NCR's S-6523, S-6561. S-6562, S-6563, S-6564, S-6565 and S-6566.
3.6 CRTS DISCREPANCIES The large number of CRTS discrepancies, listed by the SMUD contractor
[Impell] in Task 271, is another complex question. Although the large number is initially disquieting, upon examination none have any safety significance as detailed in the commentary on CRTS Action Item
- 2. One example of this is the total of 763 reported mixes of Class I with Class 2 or 3 cables. Almost all the 763 cables are in the original cable population which permitted mixing and none violated sdfety criteria. All of the 1967 Class 1 discrepancies and some Class 2/3 discrepancies have been carefully analyzed, with documentation, without finding any significant concerns. The reason for this, detailed in the commentary, is that the CRTS enhancements themselves generated the discrepancy lists which then had to be addressed. One benefit of the CRTS discrepancy process is that the total population of 23,000 cables and related raceways has been scrutinized closely and results provide additional confidence in the lack of significant safety concerns in the cable population. This issue is addressed in Item 2 of the CRTS Action Item List.
3.7 RECORDS Record control at Rancho Seco is a simpler issue. The customary industry documents of record for installed cable and raceway are the signed installation cards. The computer tracking system is used as a convenient source of data while the verification record is the installation card. At Rancho Seco the originals of the installation cards for the initial 14,000 cables and raceway have not yet been found, although facsimile record copies do exist. As discussed in the commentary to CRTS Action Item 3, we find that records for the 14,000 are apparently complete, although the clerical task of checking each cable and raceway card is not complete. Card records for the 9,000 cables and raceway sections installed after commercial operation are mostly complete. A search is being made for missing pull cards, of which 118 are safety related.
-6 -
l t
Enclosure To GCA 87-532 WIRE AND-CABLE PROGRAM REPORT (Continued) 3.8 MISCELLANE0US PROBLEMS This issue deals with the completeness of SMUD actions in identifying and resolving all cabic and raceway problems. Together, the CRTS Action Item List [ Attachment (1)], CRIS ODR List [ Attachment (2)],
CRTS NCR List [ Attachment (3)] and the CRTS Action Item Commentary
[ Attachment (4)] is the vehicle which records all questions and problems. All items with safety significance will be resolved before restart. All items with no safety significance will be resolved before the end of the Cycle 8 outage.
All items in the CRTS Action Item List will be reviewed for generic implications before resolution. When a concern has been identified, the basic steps taken by SMUD are:
- 1) Take immediate action to prevent repetition.
- 2) Identify the direct cause and take corrective action.
- 3) Investigate and identify the root cause, and if required, supplement the corrective action.
3.9 ROOT CAUSES Where applicable, root causes will be established for each item in the CRTS Action Item List. The IIRG will establish root causes for significant issues identified during the investigation of problems encountered in the 9,000 cables installed 1975 through 1986. This issue will be addressed in Item 15 of the CRTS Action Item List.
- 4. APPENDICES ,
- 1. Sampling Plan for Cable Raceway Trucking System Database (Impell Task 271, SMUD calculation No. 2-ZZZ-E0694, Revision 3, Dated March 17, 1987.)
- 2. Rancho Seco Wire and Cable Program Description and Action Plan l (District Submittal Dated April 3,1987 JEW 87-478). l
- 3. Justification for the Exclusion of the Original Rancho Seco Cable t Population from the CRTS Sampling Program (District Submittal dated July 24,1987 GCA 87-338). j V
- 4. Prior Use of 95/95 Acceptance Criteria in Nuclear Power Plant l Sampling Applications Involving Safety-Class Components and Technical Basis for Rancho Seco Sampling Plan (included in District submittal dated August 18, 1987 GCA 87-400).
- 5. ATTACHMENTS
- 1. CRTS Action Item List (3 pages)
- 2. CRTS ODR List (3 pages)
- 3. CRTS NCR List (3 pages) l 4. CRTS Action Item Commentary (66 pages)
-7 - 1 l
I-e n ( s a
~
a e
s a gg mm s
s 5
.w um m e-s e e s . e is s- -5 5
- 9 :.
a a E- .
l 5 iii gi, 1 . aI ia lI1 -!. 1, I i e i
. - - e m m. m 1 me m 1 .
m g
l-E E 2 G n G e E. e- g "l g e. E-. .
h E W 5 !$ g$~ Is E
- e !$ e g
I
_ .e- , ,, e a,
- s. _
EE b EL $ EI Er d- M g
E g_
l r am 8- e 25 Ese e Er E e R. B ~8 3
- E-e a E a cf $
e In 5
e- e s
~! as3 E' a"s 55 5
$, e t- lSE!
8]
B= **
5l 5
. s . 12 i .
8 g
5 8 ~E es E 8 55 mg a w
""3 es 8
~
~8 88
-E= 's E
s-Ew a -
~ sg sa= - -
b_I EE
=
by Ed E E 6 If a mzs$dE aa 88 $.W8m mes ee_ 28 25 G a S 5 i E_ E_
=. g .
1 0
.f ! $, $, $,
j t
I i
re 5
3 5
!w ic e
$ r+
5-5 5
5
!a 59 5?
ES !!
g 9 e e a= .e 9 e as 9s ;
t
< . 9 5 e H "g
95 e 5
- 5m 5 e g-2E .
lw E!
se c s4 w s 8 g
=
@D g
g 8! 88 g8 g
- g 3 9 = -
I c.
dB g ==
y*
w l w 8 !
r =a gw 1"g 3e e
,m a
ga se e g sg -
gs" g- e
= s_
e en 8g
=, -[ =s
=
gx E6 -w dj II EI w_
Eg 5es d wg Is t-Ed3 En gg e 9 w 5
$ gg Iw ws ,a gm =m e 2 8M4e W _
E wW EE gg Wo g$ w I_f I 5 i
l i_s se gg _ ~ m , n - - . . s _ ~
eu
_ _ _ _ _ _ _ I
i l- a m
==
w . .s $ 6
- - .e e ~ .
? 4 2 g- E n
t%. 2 - - .
dp5 a<-
00 l 5 5 s
.E 9
i -g 5
s 1
4l -
b$
E h d h
"" -m a. s a 5 sis a a as a I: 4 I
.g g d
C; a e l' U E * . S g a g W E'
$ 5 ! $ $ $ k $-
2 .
. s a a *
- ~
c E f
E g
.g #g s ee g , ,
s 5 !! !I I bd l !
9 E-e g a -s .= @' $.8 as s a og x-6 8 "g E 8 We f g.A g ut gg w $$ E # B5 # g5 &
i 3 4 b h5 EI b b NN D
A ' # d a
~ ~e a i a
n i
- 9 g
I g
IN
- g. E, h, $
, v v ,
t g 5V 57 i e 5 -
8 e
1 e
I e-m-
e 5: Em $ _ 8 *- 5 6 r ~
< w b b 8
Es $
jeI =!
'l a
21 es n 1 e
a i
1 I
i se i Es ! "
a 3
es e= ,Ns E s Il s
w
- q tx 8.s,i g . na ve rs vN
~ em s $~ wd
- w8- ri s wB w
$k 5 EN ! h $! kN hk dB y,{ gsj = : e e t : e a c :3
si a i s a a i 1
m i i i
~
4
- 5 m !i 5 i
5 i
5 i
~,
ta 54 E
5 1@5$50nu6 e g 5 9 a ~- e
- B d e
M e
M e
M g
e ss gg
._m !e n :;' a i so n-=ms=ss es E m g g-g- m i
"" 5e
- adEa5E m Em 5-e am B
i -
= E
, - $ - ~.
5 2 ::aE a $
E ! ~
3 $956 0 $
- g. ~ ; ! 8 ageg 8 =
.g
- i
-g E W $ esi: $ 2 e
8 i A s >
f =
s d E d a y g W e d d E w
5 B
6 m
e Ie 6 e
E d
e
$ @ $ $ $ h a a a a .
gg a e' i te te te e-e s si
??
e E 5 E E s
55
- s
- 5_ s_ s_ s_ 6 8 95 WE VE YE VE dh
= -
4 S S y
E Ee 5 5
$wed6 @ys =W I b,
es a 2 P -
g gd~ v8dEh w is
-avr wide e "@ %=W g 68A2 62"ga -
s 6 6Eene g
~
g SE g E
E s E :l8
- s slm:
5 5 2d sise !*hl= E sing ab!"aggi s
i !a aseg d use%
as we og g
- w=m_g s = ,3 =s agwr a aggsg e ,s w 6 n!sig masta n!as:e s!ans= m lgEg a sa di tifre !E!al ss ssrB9"$i5$
pg gsj m z o e m =
~
t i
D R I
T ~
E
(
E S' T S T
R O
S T C R F T I E C 2 R C E 3 C O R
E OT G
I 3 5 .
O T
T I
V 3
. T C E
- Y 3 O D R 2 A 7 N S R 2 T E A 2 e7 O E A L S . T N E 1 r8 I N D T .
7' . .T E S 4 N E V u
sA E IM6 T e 9
5 5
0OT 1 O E
I T
C .
I 7 3 E T 3 1 mI I
T C
T S
E oC N - F E
- 2 6 47 -
uN p E~ R l G EI T
Lf t m2 S%CD NO I
1T 0' I L 3 6
58 CO R R ETt I
l l
i .
D7 E
H o C U -
c C C6 R R ETE EELS E I S C E N L SE C 2 1
C no E N
- R E -
E 7 4
O ET H D
C t T SI 1 23 R A C
- E 1 . .23 -
S 8 W v
E I
Cf A
D I
U . .
G E E V V s L I I e M U
T A
N T
A N
m D E
R
. R E
R E W L R O
n C O T T O 0 n E H M M a t i P t
M L A E D E E g E E u E E L L n a C
T R
L E B A
L B A
L L E
N E E F
S T u
9 N T P
T P
N O
N N O
C E C IS S m L D A
S R E E E R E
R A
I I
N E P
C A
C A
t P P E D
6 7 7 8 7 7 6 6 8 7 9 9 9 8 8 9 1 9 1 1 1 9 1
5 1, , ,
7, 8 2 4 6 9 2 9 3 1
Y Y Y Y f Y R R R R R W 2 A
U A
U A
U A
U A
U E 6 B
2 Y
R B
R B B E
N R B M E
T g
g E
F A
M E
F E
F F E F 2
i t D N D n E L S A
I T I
e L A E S E
W S
m T S
N A
Z E B L
T h N H A I T R c L
. I 4
I C I M
a L T 51 R F
- L t I F
O N 4 EI B R t 4 R Y.
A 9 S 1 E
Y C
Y O
W I
N 0 L i N ID A Y
B l A U A
P E
M T
i t' 9 P
E C E I W
- O N R C T E P t
O S
E C R C S E
N L A . I A
R B
I D R E .
M C
L [
A N D
I B
I E N 0 E 2 I P G F S 0 MP D
D N I
F I
I R r T; l 2 I P T A N
O N A
N E
P W O T U
- I D
l UW O S O N N t i TI P A E I I I ! D F A
R S
F 1 R 0 I
E N S E. ER R
C S
S N I E F L E L W E P WO N MV S
E A
L V
E n l
R C
MO C S H P A
I R F W D O C C I C S I
_ . 7 7 5 1 o 8 L 1 9 0 3 7 n /1 ( 5 0 2 N 2 2 2 1 1 21 1 1 1
- - 7 m3
/ R -
7 7 7 7 6 8 P C D O M 8 8 8 8 8 L
$d' @
d Id Id l 0 d l l !
1 l
E 8 g- = bE. ~
u
- a gE. =m "d8 E- 9 gE l$W K e Rig,;is = e d we :Bi J e . !m g
Ds ag! . lgf i e "! 8Eg 11 t=
ea,e se w
r a
a 3
,= sge==e eEng scannsEg
-S-j e 9 g3 !l
. [g_
g a _
5_g 5- _,
sp se_e E R:n,p i
a 5 aa at a e aa 8 )
j
~
I
_ {
c6 i a- i s.
a- g (I
1, l[ d
!- s a g 1- 3 ag ,
,=, -
. a ,
e c d
EEs "ddqq e s a e a l{8
--a .. Q
~
g e
~ ~ E
~
~ ~
4 R E E E E
~ -
a
/ O i ! i i i i i l
N e k ,
- E a -e . - m e n g' 3-u e- ha
-a se t:1 g BW w
fU U E ed WE E - i i ! ia i!! lil 1 i! !g i
- n, s-E -
w,
- s!a
- gg ng. a =gw i e-g!! es =eg
=
g E ***
!g g EtB [8 E E
5 H
as B
a5 53-g B
a ldl5 w-Se lWH e
i s as as was GE e mE e=9 4
N
-2 B E i i = 6 s 6
g- g- .g g
og - .
2 so . x- e E o e E 5 e s 3
- s. s s s
- = d e e dg 8
ey E- le e M y ae i
3, ll8 as G5 ea
-E 5 s
l gs w" 5 *g E
'E w
96 zr eg .
- ? !B '
s g-a
-d
~
.d m
?. 6 gl ,dg
- p
- gm g =j'
< s c. gm gm : l' 18 o li" g m ~. si mi ese hgze8 la g as E aEnd EE 29 aa 8 awa mi s
[j 4
t- gn .
- t. . s e e . s is
.i d
i i m
a 8 g s e!,W e - n 25 sel -
E E
E v~
5 W "
8 ggs
-w (WE ma E e W 8 a
i E E E E a 8 ~
- ~~ ; g d i s s I a i 4 5 i
~ m i
- 1 a
M 0 f - g (
"g C
j E
5m 5W E f.s ~2 d 5"I8 55 d
m_ "a E)
= =. - #8 d~ e~ W!
t E- GMs as E8" -j ga- g,
< ga ga e- aB 5-d ~s sid s H- E l28 55 geS$ as ;
il res s gs - . ag l e
1j-la g
ga;
_Bea as g j-seri g !Em g
5:a=
nJ i g
ses
- sea sa::i En We aN ears ose as $!=
_ss 8m g4 ee m
. 3i I ? ? A $ a E $
s i = d i =
L EB .5 e
_ _ _ _ _ _ _ _ J
g- - - - , . . - - - ,,- - - - - - , ,. . . _ . _ - _ . . , . . _ _ _ _ _ _ , . _ _ _ _ . _
ga r 'o
- e. e- e e e 2 a. o
=
g !~ ! I d~ s W a a a am .. . , a d =! 3 p!ga s--s E E $ lIW g2, = 3 g a 'g
& a m - - = n -
~-
m Em*a
- E g e l; -O=g
- -= w g e -
d.
"? E g$sg
. l:. a 'WE 8E E# e g
.E.
E Ege #l-jzl d E
lle $ 2 d g' a @ s l lla!!
- m
- w. 1 _
p s :a ms 5 es:,Ha ma- d is rn Exp a e =
g 8 aaa $ aaa Aaa! ne a a n -1
~
k
, f
_ i_ g ! #_
d s -
m a g l, l, E I I E S
. l g
, e g
, i- l 8 ! ! E E E E E- E e i t e ~i a g
- i 8
ie
~
. I. l
- f. l
, i Ie 5 e
Ie i
"- l a g =
t w 5 e e 1 Eg -
S 3
ei-. [m l I!E rame E
- a ie 1 1 1
- = .= tua . u Y -i E - EgES -
E E 5k d d ' E 5 0 98 5 F
= EgEH g Ed
=
1 a
i a lg A
E n$
Wg 2 g @f~c.$ , EE g W W 6 I!$ $ 2d $$$5 5 $$ "i ! $ $.
.Q g !. !
?
e
. f. +
7 4 4
4 I
1^ l
h h h h e
Q - lI-
~
8=Iss. E s
9 h 5 O.s g , gggg , g ed'W .
- d 5 48 -
~
d E
w-gg D
- E I- E E $imE$ $ E
@ s' :: I !a! E '- ! $ eilj = E E
'ES' ( 28 25 h -(k h h 8 N
~
s< w.
i:e. -se a e *
=E=g-s W
.aw sa l$ 'g ei ou -
=,5 a g -e- e j e.
es,e d 1. Hva ng .
u u emismia!n
.: a a 8
=g m.
E' g b I E. E j E E w s gg-
- l-g g g d--- g ul 2 g 4
s
=
- m=
= wm@
NEW e .
E .~ d d E khI
- tX i
i E E E E E E E !
i i . . .
- - 6 d d M 2 2 S l k
I 4
m k Is f a
3 m
I 8 y a a
" $ I 5e 8 "g -
I $ . i E ! h 3 '
U - l f,
i E
5 k
a h
b i .
=e a N 2 2 % "kE EE s
- = h6!
- w sa se j-a E
=
~
EE E 5 eg d =
E
= g E g.
.a kgm g, r, =l e Ll b 5 E BEE kam .5 B RE sE l l.
ra N
o 8
2
~
h.
2 2
5 j
o 2
i i- _. - - -___ _ ______
]
gl!
~. D
/ E B
E B
E t I t D
E S
N h S e O D 4
N S EO S
O L
E P
O- E P p P P O
L C 0
P L O C P OI C O 0 O O O M _
T Y O t
L uf T
S L t R
R _
T T E 0
0 D
O 1 I T L N A D F 7
. 2 S R . C .
L N
- t. N OG O t G
G A P N N . T G I I . S K 0 1
I R R I I 7 A T 2 T OT 3 . T T
_ T 1 I C u 50 I I T,
.3 I S V N up M M 0 9 S S S 5
- N O
P (I 0E 9I T
4 5 4 1 0
S p
O P
S L
E L
0 6
S 8
O S 00i L -
R I I P I e7 I I
D 1 t S N T D D M D r8 T '
C D S
E G
N EC De A O I M U C S S I
B u A h E A L RT I
EE E R E B Y
R t
sA oC E
V I
u o
I J
H S
U GY CB I
U I
U 9 I
Q U
I 9 I S 9 Q l
_ l G c
T C
E h E EJW I 8 -
W E
ET S N I C S57 DS R
t E v L
O R
R E
no R E R
@1 A S V O T F R R C
S E C ._
ET E I
O C - I ET O C N N 9R " EH N R N j
s w.
l E i '
wD N O j A ET ; ,
U S l Ea A LR FT L N . . .
R' E E E V
R A
E V
E V -
S P
C C M~
t MM ~
t I R TT I
T A
R6 U
1 N
. i I
T A
I T
A -
N N ES l IW
' I S*
N N ?F N
tl E &'
D O R
N N R E
E E i
R i I I . E~ i!
C it E f S' l F /S T O N R O . T. T L
T A s t
uI; R
B I E [L R V L
E A L
P I S T T r O
N R A L u E R ET E E EAN I E E ,'
E a C
L C T N L A O B L T A T NE T B
L B
L L
S U ME EL A A t.
W CE A U E W .
3 0 R T T
~
T 8 / T r
R T
Ct P R E R I P EEI T P P O N
0 M
C n Ct 9u %
E T mE WR V
C E
@P L R
I S O
N E t
E C M m e O E C N M E I
D KCS t I P S A I I R C A A ( t 7 7 7 7 8 8 8 7 9 9 8 8 7 7 7 91 7 1 9 9 8 8 8 1 1 1 9 9 9 8 1 1 , 9 ,
1 7, 1 1 1 9 9 , , , 2 3 2 1 1 1 7 6 .
T 2 T T 9 S I
H L L S S U U Y U E
T DR C
R I
R I
R Y
L G G L G -
A P P U U U U U A A A D M N A A ~ J A A J 3 s -
t L
s N W t
n O R 0 t.
s W O
O H
E N A
H I e T N
9 S
Y A
R R
. I 6 S
S H S S ST S -
m D N A T A S S A T I C p I J S 9 A UO h t/
I R E U A A M C R c O R
( L L s N H RI a P W
U E
T T
T B Y F B C
C-N p 1 T
H I ;C C
t I f B O T i
T N
t
. 3 . -
t E N II t N T S lU I R T N E O! 7 A I M . D D lU N N E R
R R T 4 T A 0 S
E mS Y N
O E0 I E R C EF . N T H O N M L
B T A W
C T t UR m t
E F
F F
F S I T CE A WE T O R 7. F I D
D R C D U N M D C O C N RS C I D N R A LA E A SC D R F R R S E 4 D E D A T S
E B E L E
F ET L I L 4 B7 A
E D
T E
T U
T N uA u
R N E I 0 A I O F B O R S W N A T R I A D C U O R B O H ts O 4 - T D CN Y O O 1 A R E M P T
- I 0 . S N n . SC I S T
P f Y S SO O C R /
I S T
A FS S T S
R ft S .
E S L T RI A M 1 W E L
I R A C R S D -
R E CR E R S J AE B B N [i C
S T
T C D 6WO E
B L C /9 SR L L CB A
C A C C V 4 Y D S E A X LI M A A A Y P E A 1 E B R DP C B R V 2C 1 4 9 4 B C M M 3~ -
a .
4 4 4 A 9 1 9
/ O 5 6 9 6 2 2 7 9 M 6 6 0
_7 1
5 5 5 6 0 0 6 9 3/ 5 a
R C 4 4 4 4 4 7 7
S 5
- 4 S
, t N S S S S S S S _
[ l
1 h Enclosure To GCA 87-532
[
L i Attachment 4 Page 1 CRTS ACTION ITEM COMMENTARY ITEM N0. 1 DESCRIPTION ' Demonstrate that the CRTS recorded cable locations match "a s-buil t".
COMMENTARY CHRONOLOGY Employee allegations and statements as early as 1983 indicated possible deficiencies in the CRTS ' data with the possibility of both missing and inaccurate information. SMUD Nuclear Engineering Department [NED]
actions were pulled together into a single Action Plan in January,1987.
SMUD IIRG assumed responsibility for the root cause analysis of the CRTS problems and related LER's in April,1987.
In July.1986 NED authorized a contractor [Impell] to institute a review and evaluation of the CRTS program which would identify all data discrepancies, evaluate and document their significance and report to SMUD. Approximately 30,000 manhours have been expended on this effort to date and work is still continuing. Completion of this effort is Item 2 of the CRTS Action Item List.
In early December,1986, NED made a decision to signal trace a sample of safety related cables installed from 1975 through 1986. This program is detailed in the Sample Plan [ Appendix (1)]. The plan is designed to ,
statistically insure that the overall quality level achieves at least a 95% compliance with a 95% confidence level. A decision was also made not to signal trace a sample of the original 14,000 cables on the basis that the original designer / constructor Bechtel Power Corporation [BPC] had exercised an acceptable level of control. The supporting rationale for this decision is referenced in Item 7.
By late June,1987 the finding of ten major defects in Lot 1 initiated a complete inspection of all 400 cables. By early September, 386 cables have been inspected; 145 completely checked and 241 inspected in the rerouted portions. Two additione. major defects were identified as described in NCR S-6884, bringing the total number of Lot 1 defects to twelve. Sampling of Lots 2, 3 and 4 is complete.
Population lot 4 consists of a group of 78 cables which were all signal traced. This was done because the signal tracing uncovered seven Appendix "R" cables which were documented as rerouted from Fire Area 36 ,
to Fire Area 31, when this had not been done, as described in LER 87-13.
Enclosure ,
To GCA 87-532 Attachment 4 Page 2 ITEM N0. 1 CONTINUED These cables were part of the group of 28 cables installed under one ECN.
This group includes the seven cables found with incorrect routes in LER 86-10. All cables in this group [28] have now been traced with the fourteen cables described having incorrectly recorded routes. The direct and root causes of the LER 86-10 and 87-13 will be addressed by the SMUD IIRG. See the Item 4 commentary for the schedule.
GENERIC IMPLICATIONS With the completion of the Sampling Plan activity, SMUD will have established a 95 percent confidence that the CRTS data base is 95 percent accurate with respect to the location of the 2389 safe shutdown / safety related cables installed from 1975 through 1986. This is viewed by SMUD as acceptable and comparable with industry norms as described in the commentary to CRTS Action Item 28.
The SMUD evaluation of the level of control exercised in installing the original 14,000 cables indicates a level of confidence at least equal to the 95/95 target for the 9000. [See Item 7 of CRTS action item list].
New procedures and planned CRTS enhancements will be adequate to control the validity of CRTS "as-built" data. The " completeness" issue concerning CRTS data is a separate question and is addressed in Items 10, 11, 12, 13 and 14 of the CRTS Action Item List.
CAUSES The root cause is still under review. A factor is that over the period from 1975 through 1986, eleven years, different procedures have applied.
The IIRG evaluation will address the effect of differing procedures on this item [ Item 4 of the CRTS Action Item List]. From the sampling plan results the "as-built" record appears adequate.
CORRECTIVE ACTIONS The current process mandates that the installation of safety cables [ Class 1 and Appendix "R"] is witnessed by the QC inspector: this corrects a major deficiency in past practice. A new procedure NEAP 4127 " Cable and Raceway Tracking System" was issued in June,1987 and controls the methods by which changes are made to the CRTS data base and the issuance and processing of all installation cards. Corrective actions will be reviewed after the IIRG root cause analysis is completed. See the Item 4 commentary for the IIRG schedule.
l l
a Enclosura
~
1 To GCA 87-532 Attachment 4 Page 3 ITEM N0. 2 DESCRIPTION Resolve all CRTS data base discrepancies.
COMMENTARY CHRON0 LOGY Since July, 1986, a SMUD contractor [Impe11] has been performing a review and evaluation of the CRTS data for the total population of 23,000 cables. 'This review has been conducted under control of the Impell QA Program and all results have been documented and submitted to SMUD for acceptance.
Progress reports have been issued, the most current of which is Report No.
22 dated July 26, 1987. The large number of discrepancies reported are not a cause for concern. Many are not real discrepancies but are
" bookkeeping" corrections. Still others are caused by incorrectly applying current criteria to cables which were installed to older criteria. These " discrepancies" are therefore incorrectly reported and no discrepancy actually exists.
As explained in the Action Plan, SMUD will review, evaluate and disposition, with documentation, all Class 1 and Appendix "R" discrepancies prior to restart. Class 2 and Class 3 discrepancies will be dispositioned, in the same manner, after restart but before the end of the Cycle 8 outage.
GENERIC IMPLICATIONS Each discrepancy has to be evaluated separately. The evaluations may be summarized as follows:
(Note that the Action Plan totals have, in some cases, changed as indicated.)
Class 1. Item 1.0 - Intermixing of Class 1/2/3 Cables (Total 763)
None of the 763 discrepancies are valid. The total breaks down as follows:
669 Are part of the 14,000 original cables and are correctly installed. This is because the original criteria allowed mixing, provided that no Class 2/3 cables " bridged" redundant Class 1 separation groups.
I 82 Are either deleted or are routed in "special" raceways so that no mixing occurs. ,
12 Were installed post-1975 but under the original plant criteria.
All may be grouped with the 669. 1 i
l
- u. 4
g ,
p 4, pp ,
~
Enclosure )
K#
.To GCA 87-532 ,J j
4",7' Attachment 4' Page 4 l
' ITEM NO. I l g.
~
CONTINUED- j a
These cables..were part of.the-group of 28 cables installed under one ECN.
This group ? includes thecseven cables found with incorrect routes in LER
~
86-10.H A11 cables'in this group.[28] have now been traced with the e fourteen cables described:having incorrectly recorded routes. . The' direct and root'causes of the LER 86-10 and 87-13 will be addressed by the SMUD IIRG. See the Item 4~ commentary for the schedule.
' GENERIC' IMPLICATIONS-With the completion of the Sampling Plan activity, SMUD will have established'a 95 percent confidence lthat the CRTS data base is 95 percent a . accurate with respect to the-location of-the 2389 safe shutdown / safety
- related cables installed from 1975 through:1986. . This is viewed by SMUD as acceptable and'comparcble with industry norms as described in the
. commentary to CRTS Action Item 28.
' The SMUD evaluation of the level of control exercised in installing the original 14,000 cables indicates a level of confidence at least equal to the 95/95 target for the 9000,- [See Item 7 of the CRTS Action Item List].
New procedures' and planned CRTS enhancements will be_ adequate to control the validity of CRTS "as-built" data. The " completeness" issue concerning CRTS ' data .is a separate question and is addressed in Items 10, 11, 12, 13 and 14 of the CRTS Action Item List.
CAUSES The root cause is still' under review. A factor is that over the period from 1975 through 1986, eleven years,'different procedures have applied.
The IIRG evaluation will address the effect of differing procedures on this item [ Item 4 of the CRTS Action Item List]. From the sampling plan results the "as-built" record appears adequate.
CORRECTIVE ACTIONS
-The current process mandates that the installation of safety cables ~[ Class 1 and Appendix "R"] is witnessed by the QC inspector; this corrects a major deficiency in past practice. A new procedure, NEAP 4127 " Cable and Raceway Tracking System", was issued in June,1987 and controls the methods by which changes are made to the CRTS data base and the issuance and processing of all installation cards. Corrective actions will be
, reviewed after the IIRG root cause analysis is completed. See the Item 4 commentary for the IIRG schedule.
,?"
Enclosure !
To GCA 87-532 I Attachment 4 Page 5 ITEM NO. 2' CONTINUED l Cables Installed After Commercial Operation Power and Control cable trays filled in excess of 40%.were dispositioned as described for the original installation, the cable loading was verified to be less than 50 lbs/ linear foot and the ampacity was checked. The !
results were not documented by calculation, and no formal reviews were performed to verify that weight limits were met. Instrumentation cable trays filled in excess of 50% were checked to verify that the cable loading was not in excess of 50 lbs/ linear foot. Instrumentation cable tray fill between 40% and 50% was accepted based upon a generic calculation. The results of the instrumentation cable tray weight checks were also not documented and no formal 50.59 reviews were performed.
Results By July 1, 1987, all cable trays and conduits had been reviewed for fill and for weight problems. Percent fill is a feature of the CRTS program. '
Weight calculations were performed by a separate program run on a PC and performed on data " dumped" from the main computer. Results are as follows:
Instrument Tray Fills The USAR limit is 40% versus the Nuclear Engineering design criteria which ha.s a 50% fill limit for instrument cable trays. All trays have been checked for weight, regardless of fill level. No trays were found to exceed the USAR limit of 50 lbs/ linear foot. Visual checks are being performed for " heaped" or " mounded" conditions indicating possible problems during a design basis earthquake. At this time no significant problems have been found. The USAR fill limit will be changed, see CRTS Action Item 17.
ger and Control Tray Fills The USAR limit is 40%. All trays have been checked for weight, regardless of fill level. One Class 2 cable tray is overweight by 1.16 lbs assuming i that the cables in the tray run the entire length of the tray. However, because cables enter and leave the cable tray along the length of the tray, in no case is the cable tray support loading in excess of 50lbs/11near foot. In order to resolve the apparent overweight and to allow future cable additions to the tray without having to revise calculations justifying the adequacy of the cable tray, the cable tray j will be made into two cable trays by ECN R-2015 to be issued in October.
No other trays have been found with "real* fills in excess of 50 l j
lbs/ linear foot. A few additional " false" fills have been found which are in the process of correction. " False" fills occur when long tray sections l' include all cables in the weight calculations and exceed 50 lbs/ linear foot, even if some of the cables only run a short distance in the raceway section, whereas the weight borne between supports does not exceed 50 lbs/11aear foot. Documentation is provided by Impell under Task ?34.
Ampacity checks have been made on all power and control cable trays with fills in excess of 40%. No ampacity problems have been found.
_ _ _ _ _ _ _ _ _ . _ . ]
f
.k k q K ,
t Enclosure.
To GCA 87-532
< ' Attachment- 4 Page 6
< ." ITEM NO. 2 '
CONTINUED
' Summary of Overfilled Tray Review No. significant problems have bee n found to date. . Final checks are
. required to check special-conditions to verify that their impact is minimal:
Weight contribution from telephone / security cables.
Weight contributions from fire wrapping 'and cable tray covers.
Prior to restart all trays will again be checked for weight, regardless of fill-level.
Causes of Overf111ed Trays No significant problems have been found and there appears to have been a' '
reasonable degree of conservatism in the original design. Nevertheless, the lack of documented reviews in the period 1976 to 1986 is an omission.
in the design' process which should not have occurred. The direct cause
.was a lackLof procedural guidance. Enhancements planned for the CRTS software will, in the future, automatically block cable additions which ,
exceed fill and weight. limitations.' j Class 1. Item 3.0 - Overfilled Conduits (Power / Control) (Total is 108 Was 107)
All 108 are either incorrectly recorded fills, because the "as-built" conduit is larger than recorded. or are acceptable for other reasons (very short length). Quite obviously conduits cannot easily be overfilled, j unlike trays, and all 108 have documented dispositions indicating a l complete lack of either fill .or ampacity problems. ;
1 Class 1, Item 4.0 - Overf111ed Conduits (Instruments) (Total is 14; Was 13) <
- All 14 are dispositioned as false fills or similar. No ampacity problems exist with instrument cables.
Class 1, Item 5.0 - Raceway Connections (Total is 293; Was 200) l l
The CRTS program established " linkages" or " nodes" to check that connecting raceways in cable' vias did, in fact, connect. When nodes were 1 missed by. designers making the drawing changes, each missed node generated a discrepancy report for each cable using the via. All missing nodes have D
been checked and the " bookkeeping" errors corrected.
i Class 1, Item 6.0 - Duplicated Numbers (Total is 2; Was 35) i These are two " bookkeeping" errors both of which have been dispositioned
'. as having no significance.
Enclosure 3
To GCA 87-532 Attachment 4 Page 7
_ ITEM NO. 2 CONTINUED Class 1, Item 7.0 - Document Discrepancies (Total is 555; Was 551)
The 555 are a miscellany of minor data discrepancies dealing with entries covtring equipment numbers, raceway numbers, cable codes, cable data (conductor size / number) and others. All have been checked and the data corrected as needed. No data questions remain open.
Class 1 Item 8.0 - Tagging / Identification Discrepancy (Total is 0; Was 7)
The original seven items are now reported in the Item 5.0 totals.
Class 1, Item 9.0 - Missing / Unsigned Construction Cards (Total is 180; Was ~~~
53)
> The 180 cards all exist but are missing signatures. Three NCR's have been issued covering all 180. Dispositioning will require verification of terminations or cable / conduit locations, whichever is appropriate, Termination and cable verifications, about 60, are complete. Conduit data
'will be verified prior to restart.
The following Non-Class 1 discrepancies have all been dispositioned without finding any safety problems.
Non-Class 1, Item 1.0 - Intermixing of Power / Control / Instrument Cables (Total is 400; Was 125)
The USAR wording requires separation of instrument cables from power and control cables for RPS and ESFAS. USAR does not clearly address mixing for other systems. USAR also does not address or define what constitutes instrument, control and power cables.
SMUD Nuclear Engineering Procedures (NEP's, Criteria and Guides) also did not clearly define instrument, control and power cables. However, various types of signals (analog, digital) were discussed and digital signal cables permitted to mix with control cables.
The NEP's have been revised to define the separation required between instrument and power and/or control cables and to define the instrument circuits requiring separation. Details are given in the commentary in CRTS Action Item 9.
p , t' ,
4 ,
~
fg 3. , ,
2' k '
- ' u, , Enclosura -
'44 ,
R - To GCA 87-532'
, Attachment 4 Page 8-n .g. . . ,
ITEM NO. 2:
c >
. -LT)NTINUED -
J .
- i. --
'i
, , , Thel 400 reported Non-Class.1 mixes have'been.dispositionedias~ fellows:; ];
+ ,
,* T367. LAccepted:as meeting NEP.'s. {
n '
16 :To be rerouted.. I w.* 17 'Which ' require drawing changes to clarifyf service level. j q
400 Total .
Ll J
, - The original ~ design process used twisted shielded pair'(TSP) or. coax /triax
' cables for all-circuits considered as, instrumentation.~ This' has led to
]
some: confusion since no cable service levels are established in CRTS. 2 A
' future CRTS enhancement: will identify service levels for~ all cablese i
- Non-Class 1. Item 2.0 - Overf111ed Trays :(Power and Control) (Total is 153 ' l
- Was 131).
'All' trays have been checked forl weight. . Only one tray exceeded the 50 1bs/ linear foot USAR limit, as discussed previously.- Ampacity checks have been_ made .on allicable trays with fi.11s over 40%. No ampacity problems have-been found.
Non-Class 1.-Item 3.0 - Overf111ed Trays (Instrument) (Total is 18 Was 19).
. All' trays have been checked for weight. None exceed the 50 lbs/lin' ear'
- > --foot USAR limit.
Non-Class lo Item 4.0 - Overf111ed Conduit (Power and Control) (Total is 644 Was 639?
, .l A11644 are either' incorrectly recorded, because. the "as-built" conduit is
, larger than recorded in CRTS or are ' acceptable for other reasons. 'No
' ampacity' problems exist.
- 5
, ,3 \
1 1
)
1 1
i i
E_---mm_u._.__________m_________.___._._____.-___.-_._____.a.-__._m _. 5 _.
- 3. ; - -
, ya , ,
c,;;
+
a.c s ,,,
gy '
[n. [
[ , .
- 3. x , , ,
e _ %. y .a j , , - '
Enclosure r N
~~ '
< ' <F '. "To GCA 87-532-e.' ' -
. Attachment 4-a ' '
sPage;9 Q, E e'
ITEM NO. 2 M INUED se ,
- t, '
1 Resolution 'of Minor CRTS Das Nscrepancies o,
'. f A' numbe'ryufLminor Non-Class .1 data discrepancies's exist. . These are
, , summarized below.i None have any safety significance. There data' .
a (discrepancies will' be. resolved after restart butLnot :later than the Cycle '
i : 81 scheduled outage.
TNon-Class 1-
-1.0' Overfilled Conduit's (Instrument / Telephone) 151 2.0 Raceway Connections 4 1390 3.0 Duplicated Numbers 33
.4.0 Document Discrepancy,. . . .
'1594
' 5.0. Tagging / Identification Discrepancy 130 6.0.: Missing /Unsi.gned Construction Cards 92'
>Sub Total 3390-
- Secubity ,
-7.0s Raceway. Connections 177-
~8.0 Duplicated Numbers .
~29
- 9.0 ' Documentation Discrepancy -276
'10.0. Tagging / Identification Discrepancy 4-11.0' Missing / Unsigned Construction Cards- , 88 Total- 3964 j Causes' of Discrepancies I The enhancement of the CRTS software generated the list 'of discrepancies.
.The direct cause of.the discrepancies was the data base conversion and errors entered into the data base in the 1980 to 1982 time frame.
1
- The root cause~ of the CRTS problems will be determined.by the IIRG. , Both j the design and installation processes-will=have to be examined to find out 1 how data -errors came to exist-in such large numbers. The level of control {
exercised is addressed in Item 4 of the CRTS Action Item List. j CORRECTIVE ACTIONS i
Major (safety related) discrepancies will be reviewed and dispositioned. l with documentation, prior to restart. Minor (non-safety related) discrepancies will be reviewed and dispositioned, with documentation.
. prior' to the end of the Cycle 8 outage. Disposition of each discrepancy will include verification that plant design documents, the CRTS Data Base '
.and.the "as-built" plant configuration are all in agreement.
4 l
Enclosure To GCA 87-532 Attachment 4 Page 10 ITEM NO. 3 DESCRIPTION Define SMUD document of record controlling cable location.
COMMENTARY CHRONOLOGY Jn a January 7,1987 meeting, the Region V Electrical Inspector [Mr. Andy Hon] asked where cable pull cards are how kept and what will be done with cable pull cards in the future. To answer the question concerning SMUD future actions required defining the SMUD document of record for cable locations. Answers to the two original questions and the additional definitions are as follows:
- 1. NRC Questiont Where are cable pull cards now kept [ January, 1987]?
District Response: The cable pull cards together with equipment and raceway installation cards were kept in either locked metal card files in an office area of the "Bechtel Building", which is a temporary on-site construction office or in boxes in trailers used as temporary offices. ;
- 2. NRC Question: What will be done with cable pull cards in the i future [After January, 1987]? !
District Response: The cable and raceway installation cards are now !
being kept in a " vault" in the "Bechtel Building". The~ record documents are a mixture of original cards and facsimiles whch the originals l cannot be found. The vault is a secure, locked !
room with cement walls and a Halon Fire Protection System. I At this time, records are being checked to see how many cards are missing. When original cards are not found, facsimiles from the construction records will be substituted to create a complete '
record.
A duplicate record is being created on j microfilm. During March and April 1987, about 4500 cards were microfilmed and stored on the second floor of the T&R Building. This process will continue until a complete duplicate record is established.
__ _ a
WT 4 '
i
( "A{
. n v
' Enclosure.
. & .h . %g k, f
To GCA'87-532
,, ; 3 rt" hO. p 1p V '
Attachment j Page 11 g[g. g Q: , .
j ^
n =.
h Qh ' :y "
ITEM NO. 3
> 73;f 8 ..
CONTINUED
- g d7* y[ Additional Infomation
- 1. 11STALLATIONVERIFICATIONRECORDSFOR.INSTALLEDCABLEANDRACEWAY
," A
' TheIIr,stdlation' Verification Records for installed cable and raceway
'arethejoujlcards"and"racewayinstallation"cardsrespectively.
/
. #,' N AsofJuly)1,1987,118 facsimiles haze,not yetClass I cable' pull cards (originals of.all or been located. Full details missing
' cards (all types) are given in Section 4 of this commentary.
{
k, 2c ~ ENGINEERING. RECORDS FOR DESIGNED CABLE AND. RACEWAY x L ,
?\ ,,. They records are 'the input documents to the.CRTS program. These are designateA as " forms" and are engineering drawings by SMUD definition.
Q{CD
[?R . O ?
q CRTS4-1pput' drawings / forms a're as'follows:
4' Me ,.
, s h 5-1008 Raceway Inper. Document 4 .
E-1010' Scheme Cablu Input Document l- D:) E-10tfi Raceway Code Input Document E-1027 Cable Code Input; Document y,/'OV
. E-1Wil Electrical Eq:sfpment Input Document 7 , ^# ., Origidatiy new rsvu were -issued for changes. As of J June '15/1987, :6WJnew cat,le'and raceway input documents have been ay$
h ,
handled As Drawing Change Notices. Originalt of input documents are Fi being marked 1F show changes instead of issuing new foms.
[,p;
- , +
. 3. CRTS PROGRAM AND DAT/oBASE p y ]
" The function of the CRTS program and data base is two fold:
o y, la. An engineering design tool wh'ch is used by the design group to
- perform design checks and calculations. Currently the CRTS progr m checks for
Q n 9e , ,. >
7[ c 12 ; b ceway continuity ,
[' i pd;.1 .
~V
- Percentage fill
- Mixing of red'adant separation channels 4-
./ y '%
- Verifies racway service levels for compatibility v
sL 4'
N ,
X ; The CRTS is being onhanced to perform:
p s-0
- Weight calculations
- Checks on mixing of instrument cables with power and
/t control cables
. .', t V . s y tf r (c %: )'
Enclosure
! To GCA 87-532 Attachment 4 Page 12 ITEM NO. 3 CONTINUED
- b. A convenient data source which is used for engineering design information. Typical uses of the CRTS generated information are:
- Identification of cable routes Calculation of totals of combustible materials (Btu totals) '
- Weight calculations for cable tray sections GENERIC IMPLICATIONS Plant cables provide many diverse functions. The cables of safety systems provide both power supply and contrcl functions, as well as important indications to operators. The control and separation of redundant safety groups of cables and of all cables required for safe shutdown are important safety factors. The existence of reliable and accurate records concerning the location of the cables'is essential to plant safety.
With the completion of the Action Plan, SMUD will have established a record file of installation cards (originals and facsimiles) and a duplicate microfilm record. SMUD will also have confirmed that the CRTS data base is accurate to an acceptable confidence level.
With adequate maintenance of both records and CRTS data, the necessary level of control will exist.
CAUSES Difficulties in tracing records indicate a need for greater management interest in record storage and an increased awareness on the part of SMUD employees of the importance of records.
CORRECTIVE ACTIONS Replacement Cards: Replacement cards will be generated, by CRTS, for all
. missing cards. The cards will be checked against the design documents.
Checked cards will be marked " Replacement Card" and the checker will sign and date the card.
Current Process: A new procedure (NEAP 4127) was issued in June, 1987.
This procedure is considered adequate to ensure that all cards are l returned to CRTS.
- 4. . TOTAL NUMBERS OF MISSING CARDS i
The following are details of all missing cards as of July 1.1987:
l l
l l
_A
l' l
Enclosure To GCA 87-532 .
l Attachment 4 !
Page 13 ITEM NO. 3 CONTINUED Cable Raceway Tracking System (CRTS)
ANALYSIS OF 1,800 MISSING CABLE CONSTRUCTION CARDS i
July 3,1987 )
Nuclear (1) Nuclear (2) Both(3) (4) 0;, oration Engineering Depts. Pre-ECN Total' Missing Cards 797 - 44% 1Ri6 - 45% 61 - 3% 136 - 8%
' Pull' Cards 142 - 0% 177 - 11%. 27 - 1% 2 - 0.1% !
l
'From' Termination Cards 308.- 17% 146 - 8% 17 - 1% 3 - 0.2% ,
i
'To' Termination Cards 296 - 16% 193 - 10% 17 - 1% 3 - 0.2%
' Delete' Cards 51 - 3% 290 - 16% 0 - 0% 128 - 7% '
Total, Cebles in Data Base (CRTS Revision Level 1504) 23,218 i Total Cables Having Missing Cards 1,072 Fraction of Cables Having Missing Cards 4.62%
Total Missing ' Pull' Cards 348 19%
- Total Missing ' Termination' Cards 983 - 55%
Total Misst:1g ' Delete' Cards 469 - 26%
Total Missing Cable Cards 1,800 - 100%
................ \
.......... ...... j (1) Nuclear Operations [N0] initiated ECN.
(2) Nuclear Engineering [NE] initiated ECN. 3 i
(3) N0/NE jointly initiated ECN.
(4) Proposed cables entered 1976-1980, no ECN. ,
- Nissing Class 1 ' Pull' Cards 118 (7%)
.[
, O'!' i Enciasure E* , > <
To GCA 87-532
, Attachment' 4 Page 14 L
ITEM NO. 4-
' DESCRIPTION Document- the level of control exercised by SMUD in installing cable-1975-86.
' CHRONOLOGY Questions-concerning:the completeness of-CRTS data, missing installation-cards and conflicting procedures have been raised starting in 1983. The existence:in'1978 of. Quality Control Instruction QCI 107, which required;
,I the-destruction of installation' cards, raised questions concerning-
~
records. Employee allegations and statements. to the SMUD Ombudsman also tended to indicate some possible problems in controlling the installation process. 'LER 86-10 identified.7 Appendix "R" cables which should have been relocated but were not.. Additional' analysis of the cable:
- installation process is required to determine if root causes can be identified and lessons learned from them..
4
' The SMUD-IIRG has' started their review of this-item [with Action Item 25]
and has established a schedule based on availability of infomation from the Nuclear Engineering Department.
Forecast dates of other IIRG' investigations see as follows:
CRTS ACTION DESCRIPTION FORECAST'
~~TIEM 23 Determination of cause of redundant Oct, '87 cabling in same; fire area (LER 86-10) and I the determination of the cause of redundant i instrument cables routed through same fire area (LER 87-13). ;
25 Description of the installation Oct, '87 )
procedures and practices used at Rancho'Seco for the 9,000 cables added after commercial operation j (1975-86).
26 Description of the events and LER 85-16 Oct. '87 circumstances leading to the LER 86-10 Oct, '87 .
l misrouting of cable described in LER 87-13 Oct. '87 LER's LER 87-26 Oct, '87
<r 27 Description of the events and Oct, '87 circumstances leading to the 7
discrepancies discovered between the "as built" cable routes and the routes recorded in CRTS.
_________1______________t -
pg -
o _y .
>t 9!(' ;
s s + v y 8 .,
< l Enclosur:s .
l, <
To GCA 87-532 .:
1
!g * '
Attachment 4 1 Page 15 !
+
b' *
,y
' i
. . ITEM NO. 5
, I k
, a DESCRIPTION Demonstrate that no Bechtel generic design problem existed. q COMMENTARY- j CHRONOLOGY With the discovery of a misrouted RCS pressure transmitter instrument cable 'as' being a' possible cause of the August and December 1985 spurious closures of the Decay Heat System (DHS) valve HV-20002 (LER85-16),and the further' identification that the misrouting of the instrument circuit occurred during' the original design of the plant, investigation of the original cable population was begun for.any evidence of a generic design problem.
4 GENERIC IMPLICATIONS The original l Rancho Seco cable population consisted of nearly 14,000 cables, routed-in 13,000 raceways. The original Rancho Seco EE-553 circuit and' raceway _ schedules were reviewed for any evidence of a generic design problem in the original cable population. Since the present CRTS data base has been reviewed for raceway fills' and weights, channel separation 'and channel " bridging", and would have identified any such problems in the original cable population, only intermixing of power, control and instrumentation cables was examined in the original cable population.
The EE-553 raceway schedules were reviewed ;r any indication of a generic problem concerning power / control / instrumentation intennixing.
Approximately 3200 pages were manually reviewed, representing approximately 13,000 raceways. Approximately 10 cases of Class 1 intermixing were identified and approximately 60 cases of Non-Class 1
, intermixing were identified (Table 1), with no evidence of a generic intermixing problem. It should be noted that of the 10 Class I cable intermixes, that 8 no longer exist in the plant. The remaining 2 cables provide tachometer indication signals to local panels of the Bruce GM Diesels, Reference Drawing E344 Sheets 1, 4 and 5, and have no safety features actuation or reactor protection function.
Tne Class 2 Appendix "R" cables listed in Table 1 have been reviewed. On the basis of this review, the Class 2 cables IM2C3271, IM20228D and IM20229D are the only Appendix "R" circuits. These cables are routed in a four foot long, Non-Class 1 instrumentation tray X45V20 to test panel H3TP. Instrument cables included in the tray are infrequently energized and carry a low current which can not cause an adverse effect on the adjacent control cables. Therefore, the above cables can remain as routed and no corrective action is required. The remaining Non-Class I cables will be reviewed by the end of the Cycle 8 outage.
Enclosure To GCA 87-532 Attachment 4 Page 16 j CAUSES
'Both the FSAR and USAR require separate cable tray, conduit and penetration j systems for 600-volt power and control cables, and for instrumentation l cables. .The cable scheme numbering system used at Rancho Seco requires a 1 in )
the first location of the cable scheme number to designate Rancho Seco Unit
- 1. ~ A digit in thL second location of the cable scheme number designates a power cable, a letter in the second location of the cable scheme number designates either a control cable or an instrumentation cable. Without a ]'
method to differentiate the scheme cable number of a control cable from that of an inst umentation cable, intermixing may have occurred. I l
CORRECTIVE ACTION i i
Upon the consolidation of SMUD efforts to resolve Rancho Seco wire and cable problems (Action Plan, JEW-478 April 3,1987), Bechtel was asked to review the 1975 cable and raceway schedules for any evidence of a widespread problem concerning the intennixing of power, control and instrumentation cables. The ,
intermixing of instrumentation cables in power and control raceways was i identified by examining the 1975 EE-553 raceway schedules for any shielded cables in power and control raceways. In order to identify the power and control cables intermixed with instrumentation cables in instrumentation j raceways, the 1975 EE-553 raceway schedule was examined for non-shielded cables in instrumentation raceways. The results are given in Table 1.
In order to prevent any further occurrences of power, control and instrumentation intermixing, SMUD has directed by memo that an additional column be added to the "1010" drawings and DCN's to indicate the service level of the cable being added. For each added cable, the new column will indicate either P, C, or I for power, control or instrumentation service. Providing the physical designer with the necessary information to properly route newly added cable. Additional service level designators are under consideration and include T [ Telephone), S [ Security] and IE [ Instrumentation - Exempt - may mix with P and/or C cables].
l 1
Enclosure To GCA 87-532 Attachment 4 Page 17 ITEM NO. S' CONTINUED
_ . Table 1 Original Cably Population Power / Control / Instrumentation Intermixing -
Class 1 Intermixing Power Cable in Instrument 3 tion Raceway None.
Control Cable-in Instrumentation Raceway:
1M1A131D
- IM1A131E
- IM1B1390
- IM1B139E
- Instrumentation Cable in Power and Control Raceway
-1G1Q886CS IGlQ886DS 1RIC260AA
- 1RIC260AB
- 1RIC260BA
- 1RIC260BB
- Non-Class 1 Intermixing Power Cable in Instrumentation Raceway
-112E07A 112GSIGC
- 112SDPS6A
- 112E11D 112CSIGF
- 112SDPS1B
- 112E11E 112GSIGG
- 112SDPS2B
- 112E09CN 112J11EA
- 112SDPS3B *
-112E0900 112SDPSIA
- 112SDPS4B
- 112E09DI
- 112SDPS2A
- 112SDPS5B
- 112F15Z 112SDPS3A
- 112SDPS6B *
.112GSIGA
- 112SDPS4A
- 112D230B 112GSIGB
- 112SDPS5A
- 113C109A
- Cable deleted, no longer installed in plant
p:; '
.r,
[:. ; -j
[
5-Enclosure Y To GCA 87-532 Attachment 4 l Page 18 ITEM NO. 5 CONTINUED Table 1 (cont.)
Control Cable in Instrumentation Raceway-II28360CA IM2C327I 1A3A26503 1M20202B
- 1A3B470A1 II28360T II28365CA- IM2D224I 1A3B470A2 IM20228D 1A3B470A4 II28365X-II2G996D IM2D229D 1A3P200B2- 1M2E203B
- 1A3P200B6
'II2N150LF 1A3X520B 1A3X520H
-i '
Instrumentation Cable in Power and Control Raceway II2R301B 1R21460B II2G201 1R2PBTPA 112R520AB 112G202 1R2T250A-II2G203 II2R520AF II2G204 II2R520AJ 112R532AB l II2G417
- Cable deleted, no longer installed in plant i
l i
I l
- - - -- 1
r= -
. , r s ,
u p' _h [$ !
,,_ 7 .
' ~
l_ , , __
.L~ -
[_\ .~}l< ,
. Enclosure-u To GCA 87-532-
- , a Attachment 4 y ,
Page 19 4.
c.
L :
, 1 ITEM NO. 6
- 1. ,
4 DESCRIPTION Resolve' overfill / overweight questions; including USAR and 50.59.
' L ' COMMENTARY CHRONOLOGY
, 'In February,:1986.0DR 86-125 was prepared as a result of an' investigation following allegations.-of raceway overfilling. _ The DDR examined instrument
, . cable tray overfilling. because instrument trays are filled to a higher level than power .and control trays, and determined-that for the .caDie' tray with the highest fill e,that the cable loading did,not exceed 50 lbm/ft.
In addition, it was verified that the actual cable tray loading was used'
~
in the fire hazard analysis. and also that the cable; tray heat derating was
-acceptable with respect to,the cable ampacity. As a result of the above -
-investigation,'38 Class 1 overfilled trays and 150 Non-Class 1 over. filled
- trays were: identified and subsequently: reviewed for overweight, as described in the commentary to CRTS' Action Item 2. ;
ODR 87-204 was initiated in' February,1987, as a result of concerns that cable trays with fills less-than 40%, might in certain unique circumstances,' exceed the cable loading of 50 lbm/ft. LER 87-24 was also !
initiated to detennine the deportability of the identified problem. !
)
GENERIC IMPLICATIONS ;
1 The Rancho Seco USAR limits the fill of redundant cable trays-to 40%, so as not to exceed the cable. loading of 50 lbm/ft used in the cable tray support design. Cable trays do exist whose fill exceeds 40% and were dispositioned during the original design process. Power and control cable -
trays filled in excess of 40% were checked.to verify that the cable ,
loading was not in excess of 50 lbm/ft. In addition, an ampacity check was performed. Instrumentation cable trays filled in excess of 60% were !
checked to verify that the cable loading was not in excess of 50 lbm/ft. '
Cable tray fill between 40% and 60% was accepted based upon a generic calculation. Although the'above calculations were. performed during the original design process, the calculations have not been found.
k I
m ..w ,- g' hhM h '
-Enclosure M,[ J 1 To GCA 87-532 3- a-
[ ,
Attachment 4 Y: Page 20 4
- ITEM NO. 6 CONTINUED H
$ Power and contro1Leable trays filled'in excess of 40% after commercial 9 < ' operation wereidispositioned as described for the original installation.
- For instrumentation cable-trays filled-in excess of 50%, the cable loading' was' verified not to excee'd L50 lbm/ft. the.results' of the weight checks ,'
performed after commercial operation were not documented and nofomal
? 50.59 reviews were perfomed. As of May, 1987 all cable trays have been.
reviewed for. fill and weight problems', with only one Class. 2 power and.
controli cable tray requiring physical modification as . described in the
' commentary to CTRS Action Item 2.
The USAR limit ~ 1s 40%,for; power and control tray. fills. All trays have been checked .for. weight (regardless of. fill level). 'Only oneltray has been found with an." apparent" fill.in excess of 50 lbs/ linear foot.
requiring physical modification; " False" fills have been found where a ,
long tray'section; includes all cables lin the. weight calculations l(and ..
^' exceed 50.lbs), whereas the weight borne between supports does not exceed 50:1bs . Ampacity checks have beenlmade on.all. power and. control < cable trays. With fills in excess of '40% 1 No ampacity problems have been found.
The.USAR limit is 40% for instrument tray fills and is at variance with the Nuclear Engineering criteria which has a 50% f111~11mit for instrument 1 cable-trays. All trays have been checked for weight (regardless of fill ,
level); No instrumentation trays were found to exceed the USAR limit of J
.50 lbs/ linear foot. Visual checks.are being performed for " heaped" or i
'" mounded" conditions indicating possible problems during a-design basis j
, earthquake. At this time no significant problems have been found. The i USAR' wording'will be revised, .[See commentary to CRTS Action Item 17], and the fill limits will be defined in the NEP's.
1 q
In summary, no significant problems have been found to date. Final checks on weight contributions from telephone / security cables and weight contributions from fire wrapping are required to verify that their impact is minimal.
L" I
L i
1
.. I
.,p.
ry(( 0 II }: A e
[
~
qq ,
~ ' s
+
y,~ c i
y, ,
.3 7 .,
]Q.p;g. >
syc y Enclosure-g ; 72. <w j ,; , ; ,
o To GCA 87.-5321 ,
M,; y ,, ,
> ' Attachment 4
+,
Pace 21
, g --
,. . 'd
) '
5
L.g, '
' ITEM NO. 6' ' '
CONTINUED-
/ , j j' . t j, {
>t.
4(
l gs >
.CAUSES
' l As. evidenced by the discovery of only;one " apparent" problem con ~cerning 1
. overfill' ed cable trays, the original' 40% f111.11m1t..was-a very-
.g conservative' requirement in' the -original. plant design. < However, the:
. absence-of: documented 50.59 reviews for<those cable. trays' whose fill was
" -exceeded. [ post-commercial $ operation] is: a cause for concern. The direct" <
e
' causetof both overf1114 and overweight conditions lacking the documentation ~-
E valida' ting their.. acceptability.was La lack;of procedural guidance. -
9
- CORRECTIVE ACTION:
- r '
r
-Immediste corrective action has been to resfew all cable tray weights
~
-p a-
-n ,regardless of fill le' vel-[-.See commentary on'CRTS Action Item 2].
^ u . Additionally, for_ new design work [added cables], all' power. and: control-
- trays which exceed .40%, fill are' checked for weight and ampactty;;all . '
s
-"' *. , .-instrument' trays whose fill exceeds 50% fill, are checked for ' weight. . NEAP
- - 41271 requires. all DCN's. which add cable and increase trayL fills- above 40% '
to' be referred back to NED for review and documented analysis. In addition, the 50.' 59 review concern will' be resolved under CCTS Item No.' .
- T8704093070, with a' forecast"date of October 31,-1987.
y -.
1 \
1 i.
I- p_
l ..k g
)
'l l m, u l
1' l ,
1 l
Enclosure To GCA 87-532 Attachment 4 Page 22 ITEM NO. 7 DESCRIPTION Justification for not sampling the original cable population.
COMMENTARY, CHRONOLOGY As a result of employee allegations as far back as 1983, and with the June 1986 identification of seven misrouted appendix "R" cables, a decision was made in December 1986 to signal trace a sample of safety related cables, installed after commercial operation in 1975. The original cable
-population of 14,000 cables was excluded from the sampling plan, because the design, installation and inspection of the original cable population by Bechtel Power Corporation, Rancho Seco A & E and Constructor was governed by a quality program sufficient to control the physical design and installation of the original cable population, juMMARY Justification for excluding the original cable population was presented by SMUD, during the June,1987 NRC inspection visit, in the form of a report. The report, titled " Justification For Not Sampling The Original Rancho Seco Cable Population," was formally transmitted by GCA 87-338, dated July 24, 1987. The report demonstrates that Bechtel had in place and used a rigorous quality program sufficient to control the physical design of the original cable population. In contrast to those cables installed after commercia'l operation, the original cable population was installed while the plant was in a construction mode, under a uniformly consistent set of rules and procedures. The procedures did not vary during the design, installation and inspection of the original cable population and it will be shown that these procedures were rigorously followed by a relatively stable and well trained workforce. The justification for not sampling the original cable population was transmitted by GCA 87-338, dated July 24, 1987 and is Appendix 3 to the Fire and Cable Program Report.
n i
I. f' L Enclosure To GCA 87-532 Attachment 4 l Page 23 {
l l
ITEM NO. 8 I
DESCRIPTION Resolve all known physical problems, j COMMENTARY I
CHRONOLOGY Physical problems related to the Rancho Seco cable and raceway installation have been identified by LER's 85-16, 86-10, 87-13 87-24 and 87-26. In addition Impell under Task 271, has identified, with
' documentation submitted to SMUD, additional CRTS data base discrepancies, although not all are physical problems [See commentary to CRTS Action Item 2]. The idantified physical problems are of the following types:
Overfilled / Overweight Cable Trays (LER 87-24)
Refer to commentaries to CRTS Action Items 2 and 6 for discussion.
Intermixing of Power / Control / Instrumentation Cables (LER 85-16 and 87-26)
Refer to commentaries to CRTS Action Items 2, 5 and 9 for discussion.
Lack of Configuration Control (LER 86-10 and 87-13)
Refer to commentaries to CRTS Action Items 1, 4 and 23 for discussion.
Lack of Redundant Class 1 Channel Separation No identified problems of this type have been found to date.
Lack of Class 1/Non-Class 1 Separation .
i As described in the commentary to CRTS Action Item 2 none of the 763 intermixes of Class 1, 2 and 3 cables are valid discrepancies.
The cables were either installed under the original plant criteria, which allowed mixing or are either deleted or routed in special" raceways, so that no mixing occurs.
CAUSES Refer to commentary to CRTS Action Item 15.
< Enclosure To GCA 87-532 Attarpment ;
Page 2t,
, ITEM a0. E
_CONTINUET CORRECTIVE ACTIONS The following corrective actions have been taken to resolve known Rancho Seco cable and raceway physical problems, and to prevent their reoccurrence:
Overf111sd/0verv:sicht Cable: Trays Immediate corrective action taken as a result of ODR 86-125 and LER .
87-24, was the rev.iew of all cable tray veights, regardless of fill !
level. As a result of the cable tray weight review, one Class 2 power and control cable tray was found to be overweight, ECN R-2015 will be issued in October'to divide the tray into two trays to resolve the apparent overweight. Corrective action to prevent reoccurrence has been the revision af procedure NEAP 4127, " Cable Raceway Tracking System," to require that data contained in DCNs to CRTS-related drawings be " error f.w" whan %put to the proposed ,
CRTS database. Should an error re w e indic6te an overf111 '!
condition, .then the DCN is returned to the originator for resolution. In addition, the USA 9 will be revised to: reconcile discrepancies in fill limits for Instrumentation cable trays to be consistent with NEP 5204.22, [See commentary to CRTS Action Item'17].
Intermixing of Power / Control / Instrumentation Cables l
Immediate corrective action taken as a result of the identification of an SFAS instrument cable routed through power and control raceways, in LER 85-16, was the review of the CRTS data base for further intermixing [See commentary to CRTS Action Items 2 and 9],
as well as the examination of the original cable population for a generic intermixing problem [See commentary to CRTS Action Item 5].
The intermixing identified by LER 85-16 has been corrected by ECNs R-0459 and R-1295. Further intermixing has been identified by CRTS data base reviews, as identified in'fER 87-26, and by cable signal 2 tracing as identified by 0DR's 87-604-and 87-723 and are corrected ;
by ECNs R-1785 and R-1786. Sixteen Non-Class 1 intermixes requiring l relocation were identified by Impell as documented by CPR's i CPR-0611, 610, 885, 638, 640, 622, 642 and CON's CON-584 and 742 !
contained in Impell Calculation No. 271-101-109, Rev. O. Presently {
the calculation is under review by SMUD with a revicw completion date of October 31, 1987. Corrective action to prevent reoccurrence !
of power / control / instrumentation cable intermixing has been the revision of Design Guides NEPM 5204.22, " Cable System Design, 1 General," and NEPM 5204.43, " Instrumentation Systems Shielding and Grounding and Surge Protection," to clearly define the physical 3 separation requirements for power, contrM and instrumentation !
circuits and to provide definitions of whe cable service levels [See 1 commentary to CRTS Action Item 9]. In addition, the USAR will be I revised to remove any ambiguity as to the applicability of intermixing restrictions to RPS and SFAS in USAR section 8.2.2.11.H l
[See commentary to CRTS Action 17]. 8
mm
((is g .
- - - ~ ~ ~~= - - ~ ~ - - - - - - -
x .. ..
Q }
- M, ' , 3,', g,,^ -
, [
< ' n ,
p; .] y; ; m, n;ea ,
. Mt ' Enclosure 1
.'2 To-GCA 87-532
, ' ' f, ,
JW . ' Attachment 4 *
}'f( j Pane 25:
g; 1 , >
L. <
1 ,
<~
l
- n j
t ITEM NO. 8" '
r.
'j , ; CONTINUED
]
$@ W I ny LhekiofConfigurationControl l fm 1, e>
%/ .
Immediate. corrective-action,Eas:a result of. the identification of
?
- the cable misroutes in LER 86-10,'was to initiate the. Rancho-Seco
%,L'z Nm ,'
cable sampling to establish'a:leveliof confStence in the cable'
' installation. , The LER 86-10 cable misroutes' were' corrected by ECN o S R-0765, which 'is' construction complete. The' additional cable ~
4
'7 '
> ; misroutes!1dentified during the cable sampling activities' and l documented by. LER 87-13, were rerouted by work request.;
p1 s ,
m ,
1 'Correctivefaction to prevent. the reoccurrence of cable misroutings
.has~ been to revise the Modification' Procedure / Inspection Standard y *J ^
y~ MP/IS. 307, " Cable: Installation," to require the use of design ,,
drawings of the latest revision when: installing cable, and:the M g ; requirement that' the' cable. routing infomation on the E-1010 series j
drawing match that'.on the. applicable cable. installation card..
? . Witnessing requirements for cable = pulls have also been clarified in -
' / MP/IS' 307 to. require that cable installation verification'shall:
consist' of. witnessing the installation of the ' cable.
T5 ' Lack of Class 1/Non-Class 1 Separation No. corrective; action necessary, as n'one of the 763 intemixes' of Class = 1', 2 and 3' cables are valid discrepancies.
k f
, i
Enclosure To GCA 87-532 Attachment 4 Page 26 ITEM NO. 9 Description Resolve power / control / instrument cable mixing concerns.
Commentary Chronology LER 85-16 Rev. O was the first documented evidence that instrument cables had been mixed with power and/or control cables at Rancho Seco. Since this discovery, additional " mixing" has been found and details are provided in the commentaries to CRTS Action Items 2 [ partial] and 5.
Generic Implications The concern is the avoidance of unacceptable noise levels, caused by cross-coupling between adjacent conductors, in instrument circuits. The.
level of noise is a concern for analog circuits and some digital ci rcuits. No concern attaches to cable insulation levels since all power, control and instrument cables have 600 volt insulation ratings and
' additional protection in the fonn of a protective outer jacket.
The ability of a circuit to tolerate noise is a function of the equipment connected to it. The type of equipment and the provision of noise
" filtering " components both play a part.
The original design approach at Rancho Seco was typical of plants of similar vintage. The raceway design for the original 14,000 cables provided two service levels for 600 volt class cables [NEPM 5103 Section 5.4.5.)] (1.b) 480 Volt (and below) power, DC and control and (1.c) instrumentation. No explicit definitions existed for either power, control or instrument circuits. Service levels were indicated for raceways as follows:
For Class 1 power and control raceway, the raceway designator begins with either the letter L, M, P or W for Channel A, B C, .or D, respectively. For Non-Class 1 power and control raceway, the raceway designator begins with the numeral 7.
For Class 1 instrumentation raceway, the raceway designator begins with either tne letter A, B, C or D for Channel A, B, C or D, respectively. For Non-Class 1 instrumentation raceway, the raceway designator begins with the letter X.
c . _ _ _ _ _ _ -
X Enclosure i
To GCA 87-532 6'< Attachment '4 Page 27- !
ITEM NO. 9 .
CONTINUED
, : Conduit is' differentiated from cable tray by having all digits I after the first' letter or number; cable tray is identified by
.having both letters and numbers after the first letter or number
. raceway designator..
For example:
l L27AF1 - Channel A Power and Control Cable Tray M47223 - Channel B Power and Control Conduit
.727BA1 - Non-Class 1 Power and Control Cable Tray
.732007 ' Non-Class 1 Power and Control Conduit A32AB2 - Channel A Instrumentation Cable Tray D44301 - Channel D Instrumentation Conduit
'X44AD3' Non-Class 1 Instrumentation Cable Tray X56032 - Non-Class 1 Instrumentation Conduit Scheme cable numbers 'did not indicats the service level [P, C or I] for cables; however, a standard practice was used which identified all 600 volt' shielded cables-[ twisted shieked pairs,. coax, triax etc] as instrument cables. This practice allowed latitude to the designers in ;
classifying circuits as " instrument" when the circuits were shielded. '
For example with this approach low amperage (0.5 amp) 120 Volt power supplies could be installed using shielded, twisted pair cable and run with signal cables. When a field component (e.g. flow transmitter) was provided with only one entry [ conduit hub] this was an obvious practical
, approach, meeting the equipment suppliers intent. j I
For safety circuits an unacceptable noise level is a plant safety l issue. For this: reason-the USAR wording requires separation of l instrument cable'from power and control cables for RPS and SFAS while ,
not explicitly addressing' other. systems. In practice, the design intent J has always been to maintain the same separation for all systems. Design !
Guides written in 1984 and later have attempted to provide more explicit 1 direction with the result that the design intent for the original 14,000 l cables and cables installed later. has b'ecome blurred.
Causes The direct cause for each id'entified problem [CRTS Action Items 2 l (partial), and 5] will be addressed in each individual commentary. Not all' identified problems are, upon examination, real problems. A major J cause of both real and incorrectly identified " mix" problems is an inadequate definition of design intent in both USAR and design documents.
A description of the events and circumstances leading to the discrepancies identified in LER 87-26 is in preparation by IIRG and will be included'in the October issue of the report.
cy a # ; ,, % m y)-
E '
. ,f . ; , ). '
('u QUVs-e ,
/:. . '. ^
Enclosure y T""
$ &, < , .To GCA 87-532
.g% y l m ,
. Attachment '4 1 s,
- Page 28-E4< -
(- j ITEM NO. 9
~
E!4 CONTINUED 4
g i #
4 Physical Rework 1 ,
, ! Corrective ~ Actions
- a. s The physical reworking-oficables because of mix problems is identified '
in'the following: ;
1 LER 85-16. Seven cables required relocation. NCR's S-5263 and S 5968. O
- were . jssued. . ECN's R-0459 and R-1295 detail the work.
y A LER 87-26. Twenty-eight: cables. required relocation. NCR's 'S-6561, ,
S-6562, S-6563. S-6564,~S-6565!and S-6566 were issued. ECN R-1785 and ECN R-1786 detail the work.o ~ ECN R-1785 was issued in August,1987. ECN R-1786 was: issued on~ June.29, 1987 and the forecast construction- -i' completion'datefis August, 1987..
CRTS' Database Discrepancies [CRTS Action Item 2]- 4 Sixteen routing errors requiring' relocation were identified:by Impe11 as , q documented by CPR's CPR-0611, 610,=885, 638, 640, 622, 642 and CON's.- '
CON-584 and:742 contained'in Impe11' Calculation No. 271-101-109, Rev.
.0. Presently the calculation;is under review by SMUD with a review completion date of Octooer 31; 1987. ~ !
f
. r. .
C_orrective Actions - Changes to USAR and Design Process:
CRTS Data Base' l
'l y Since July,1987 the cable input documents [ Form E1010] have been 1
. required to . carry a designation P '[ Power], C [ Control], or I #
g [ Instrumentation].to indicate service level and assist in routing the cable in' raceways of the proper service level.
~ ;
~ Additional' service level designators are under consideration and include T [ Telephone] S [ Security] and IE [ Instrument-Exempt may mix with P and/or C cables]. 1 i
.< A CRTS software' enhancement is planned [CRTS Action Item 10] which will: ]q M'
- Add a field for cable service level [P, C, I etc]
- Add a program feature-to check cable service level against ~
raceway service level.
l' t I i
! 1.t.
_i_ - - __ , _ . _ _ _ _ _ _ . _ _ _ - . _ _ _ _ k
I' I
I' Enclosure L To GCA 87-532 h Attachment 4 Page 29 .
ITEM NO. 9 CONTINUED i
Revisions to Design Documents The physical separation requirements for power, control and instrument circuits have been defined as follows:
Separate ~ condt Ms, ducts, penetrations, and cable trays should be provided for the following types of circuits:
(1) Medium voltage (6.9kV) circuits.
(2) ' Medium voltage (4.16kV) circuits.
(3) Low voltage power.(480V) circuits from 480V switchgear, with maintained spacing in trays.
(4) Low voltage power (480V and below) control, and annunciator window input circuits, and selected shielded instrument circuits approved by the Electrical and I & C Supervising Engineers.
(5; Instrument circuits requiring separate routing.
In vertically stacked trays, cable trays should be arranged in the order given above with the medium voltage cables in the highest position in the stack.
Control . cables may be pulled with low voltage power cables, except when their respective conductor sizes differ too greatly.
The instrument circuits requiring separate routing are the following:
(1) All signal circuits from process instruments such as thermocouple, RTD's, transmitters, neutron flux detectors, accelerometers, level elements, radiations monitors, etc.
(2) All signal input circuits to computer and Anatec multiplexer, except for selected circuits which the Electrical and I & C Supervising Engineers specifically approve in writing for l routing through power and control raceways.
1 (3) All low energy level circuits (analog or digital), interf acing l between instrument cabinets, and signal output circuits from )
instrument cabinets which control the plant equipment or i device. ;
}
p)J
) ~ ,.,. s t
?' i. .tl L: _) ?; *
' ( ,t
~
c ,
Enclosure yg l + '
'To GCA 87-532-7
. Attachment" 4 r 1 Pace 30 3.
ITEM N'O. 9 ..
CONTINUED-
"(4)L All circuits requiring :oaxial .: twinaxial.: triaxial'.. and-i
& fiberoptic cables. (Class 1 ex-core detector cables such as.
L: 1 those for source range. and power range' ion chamber circuits
^,
q must be run in dedicated rigid steel conduits.)-
(5), 'All low level-and higher level analog circuits as addressed in:
Electr'ical ' Design Guide .NEPM 5204.43, sections 5.5.4:8'5.5.5.
a
' ^
3.1 -(6) All-signal circui.tsi to panel mounted instruments that are part
~ of a process instrument loop and shown on instrument loop
- diagrams..
(7)- All ~other circuits designated by the-Instrument and Control
~ Group as instrument circuits.
L Revisions to the- following Engineering Design Documents .were completed.:
in July,'1987. These, revisions-are being applied to all new cable work.
NEPM 5204.22 Design Guide -: Cable System Design, General-NEPM 5204 43- Design Guide - Instrumentation Systems Shielding and Grounding and Surge. Protection Revisions to USAR o.
'See commentary to CRTS Action Item 17.
1 l
+
' k, , l
Enclosure To GCA 87-532 Attachment 4 Page 31 ITEM NO. 10 Description Demonstrate completeness of CRTS including software verification and validation.
COMMENTARY CHRON0 LOGY General background and initial actions, concerning the CRTS program, are described in CRTS Action Item 1 [as-built verification] and 2 [ data discrepancies]. The completeness question has two issues:
- 1. Installed But Unrecorded Cables: Whether the CRTS data base includes all cables installed in the CRTS listed raceways.
- 2. Dependable CRTS Program: Whether the CRTS software is complete, reliable and error free.
Generic Implications
- 1. Installed But Unrecorded Cables Cables of two specific systems have been identified as having i incomplete cable records: !
l Security System - CRTS Action Item 11; approximately 180 cables of a total population of 2000 not in CRTS.
Communication System - CRTS Action Item 13; approximately 450 cables, of a total population of 1500, not in CRTS. [ Refer to referenced Action Items for additional detail.]
The possibility has also been raised as to whether procedures existed which permitted cables [other than security / communication] to be installed without entries being made in the CRTS data base.
The procedure question is being investigated by IIRG. An IIRG i report is in preparation which indicates no evidence that cables were installed without the CRTS data base being updated.
As of September 1987 the problem of unrecorded cables appears ,
confined to some security and communication systems without j generic implication for other systems. Security and i communication cables are installed only in non-safety related raceway which lessens the level of concern.
l '
l L
L 4
I L
Enclosure i To GCA 87-532 i
Attachment 4 l Page 32 l
ITEM NO. 10 CONTINUED Concerns exist, with installed but unrecorded cables, related to raceway weight, to raceway fill and to the quantity of !
combustible material in open cable trays. However, the !
quantities are small and without significant safety impact.
- 2. Dependable CRTS Program
'l The CRTS software program was written by Control Data Corporation [CDC] for SMUD. The program was run from 1980 i through 1986 on a CDC main frame computer in Kansas City. The !
program is currently run on a CDC Cyber 180-830 computer !
installed at the Rancho Seco jobsite. Maintenance and enhancement is provided by CDC. The CRTS data is down-loaded to a network of four personal computers for ease of handling by CRTS personnel.
l The CRTS software program is not a verified program meeting Nuclear Quality Standards. However, subroutines written for and executed on the PC network are verified under a contractor ,
[Impell] Q. A. program.
The CRTS software program inventories cable and raceway data .
and performs design checks. The CRTS data base is also a :
source of data for other calculations [e.g. combustible j loadings of cable insulation] and a source of infonnation on cable routes. The dependability of the CRTS software is therefore of safety significance to the plant and the }
software requires verification to the requirements of the SMUD Quality Program.
The design documents issued for construction have always included both the input documents as well as the CRTS generated installation cards. This process provides l verification of the cable route since any difference between design intent [ input document] and CRTS record [ output cards]
is readily apparent.
4 &
"} l 1
T (
Enclosure-To GCA 87-532
'x ,
Attachment 4 Page 33
.i .
ITEM NO. 11- :
, p ,
DESCRIPTION- -
Show to what extent security cables are documented in CRTS.
~ COMMENTARY' f
, CHRONOLOGY -
, LODR 87-409, dated April 9, .1987 reports that 630 telephone and securtty system cables are installed in the plant with incomplete documentation.~
Approximately 180 ' cables of a total population of 2000 security cables- I are.not in CRTS.- l 2
All Security cables are recorded in one of three data bases::
1.. EE-553 (KL);
.2. .CRTS
' 3. . PC Data Base. .
All- security cables are ir, Non-Class :1 raceway.
GENERIC IMPLICATIONS The concern with the incomplete documentation of the plant security cables is'due to potential impacts upon cable tray weight, fill and combustible content as well as separation and mix concerns. However, since the security cables are in'either dedicated conduit or in Non-Class l' raceways, there is no'significant impact upon safety cables.
Resolution of this problem will be completed by the end of the Cycle 8 outage.
CAUSES The cause of the' incomplete security cable riocumentation has not yet been determined.
CORRECTIVE ACTIONS The immediate action to prevent further undocumented security cable p additions to the plant has been to require all design work to be reviewed
.by the Nuclear Engineering Department. Additional actions may be taken i later after further investigation'of causes.
1 l
i L __-_-- _ - - .- -- - -- - D
4 I ' h'd, j (
I ' fa g,; ,
j' 1
N'
f;' * , i 1_ : .
' ^\
, + .ff ': . ' m,
. , .; ..g < g ,
W Enclosure s.
To GCA 87-532
!,iAttachment 1
h:
..4 I? -f1 Page 34
- p. '
- , +
h, s
ITEM NO. '12 :-
l1
'e p ?. .
- DESCRIPTION- -
Complete securf Q: cable documentation.
91
[<
E
< . COMMENTARY 2 i # To be' performed prior to the end of.the Cycle 8 outage. .
s i
- 3. .
I i:
1
'k,',
[
s I 4 a
I,
.1 1 .
i i
,p 5
i i
f
. - t '.
9 6
..-___m.__ _-_______________ _ _ _
i Enclosure To GCA 87-532 Attachment 4 Page 35
, ITEM N0. 13 Description Show to what extent communication cables are documented in CRTS.
Commentary-Chronology ODR 87-409, dated April 9,1987, reports that 630 telephone and security system cables are installed in the plant with incomplete documentation.
The communication cables include those from the following systems:
PA - Public Address [ Dedicated Conduit]
SP - Sound Powered [ Dedicated Conduit]
CBX- Computer Based [Non-Safety Tray and Conduit]
Exchange [ROLM]
CBX cables include circuits for VHS radio and microwave link.
Communication cables are shown on series 700 drawings and ECN's.
Generic Implications The concern with the incomplete documentation of the plant communication cables is due to potential impacts upon cable tray weight, fill and combustible content as well as separation and mix concerns. However, since the communication cables are in either dedicated conduit or in Non-Class I raceways, there is no significant impact upon safety cables. Resolution of this problem will be completed by the end of the Cycle 8 outage.
Causes The cause of the incomplete communication cable documentation has not yet been determined. A potential cause is that since the communication cables were installed by the Electrical Maintenance Department, conflicting procedures may have led to incomplete communication cable documentation.
Corrective Actions The immediate action to prevent further undocumented communication cable l additions to the plant has been to require all design work to be reviewed by the Nuclear Engineering Department. Additional actions may be taken later after further investigation of causes.
1 l
i
~ _ _ - _ _ - _ _ - . .
g,-
no a' .
- 1 i
4c' ,
h;7JU [
k .f. ' I n if -
< Enclosure- i k E."
-To;GCA 87-532: !
o Attachment '4 a Page 36 l
- u. ,
)..,
L ITEM-NO. 14- ]
11 4
t1 i
L,
. DESCRIPTION Complete security cable documentation ~.
'COMMENTANY' ls 9 r.
-To be performed prior to the end of'the Cycle 8 outage, i o
. i.
1 2 '
.i
.l i
1
-j L ii j i
'I i
, ) 'T I
1
, a J
1 l
l l
1 i
l 1
t
- n . .
m,) ,. '
.g.-
,.V... ,t e 4 .,, , I I,' r .
s3 f. ,
. . , s e t ,q i ; +- :p, d:>
ll1, >lll
' *
- I c , ' e_ :
_. i
, ;;:j qT ' a , !!
,a J,' ,
Enclosu're "1 3
. 'To GCA 87-53?
' . Attachment 4 ~
lwf. , Page 37-
..y W-ITEM NO. 15
'$ , ; . j '
.>., DESCRIPTION real and complete' rod cause evaluation of all cable
. roblems.
y . . ;c -
,,x ..
.t.
L / ,
i.,n '
. COMMENTARY .
s .
-t I c
To be provided in'the October Sire and Cable Program Report.
, 5 , u.
.i< ,
p I ;
"{. ~[i 7
46 ,
- e; Y
j'< ' '
,l( ', . . - .,'4 i. 4 l, .
I )
, , Ap' 'r',, , Y ,
)
t L je' !
..) .
[
I l
{ { '
! i
(
, f i
' k' o
i > f
.4
('" :
)- ~
, .,, 8 r, ..s,. ./ }l, L. w'.
c
- l,'Ii . g ; , .l ( b
!I
.j,( yf ' .:.
}i;*t; m- . 9 ,'/.' ,
c;
- h , .' ;. ,f, l'
- a. . x v ,
I
- ., v
!.:e ,, ; '
- .L r ;\
r?
f
'I 4
l
,$ (. '. , .[ ' *j v
f 'f , ,..
'l t )
I 1
.- I
.. [,t1 1
f s li 1 l<
.; g3t.w .- __ - .- _ .- - a
Enclosure To GCA 87-532 Attachment 4 Page 38 ITEM NO. 16 DESCRIPTION Define major / minor / insignificant defects.
COMMENTARY CHRONOLOGY The Sample Plan [ Appendix (1)], prepared by Impell under SMUD Task 271,
~ 'provides in Figures S.1, 9.2 and 9.3 a flowchart methodology to classify e ' the types of defects discovered by. the circuit tracing walkdowns, into major, minor or insignificant defects. The NRC requested in the May 6, 1987 meeting between the District and the NRC, that the District provide formal, written definitions of the types of defects.
Major, minor and insignificant defect definitions were given verbally to NRR during a site visit June 15 through 18, 1987. Definitions [see below] will be included in the next revision of the Sampling Plan. The following was explained to NRR.
t The yord " defect" is used in the Sampling Plan to describe a cable route
( which is checked and found to differ from the CRTS recorded route.
r Defects are classified as either " major", " minor" or " insignificant".
The clas'sification is determined by reference to a set of decision diagrams included as Figures 9.1, 9.2 and 9.3 in the Sample Plan
[ Appendix (1)]. For the convenience of reviewers the following definitions will also be included:
Major Defect
- /
A major defect is a cable route which differs from the CRTS recorded route and the difference constitutes a violation of the plant safety or desip criteria. Corrective action is required.
J.!!.n_gg.,Defeet A midqr defect is a cable route which differs from the CRTS recorded route and the difference does not constitute a violation of the plant safety or design criteria. The corrective action is to correct the engineering record with no change to plant configuration Insignificant Defect An insignificant defect is a cable route which differs from the CRTS recorded route only to the extent that typographical errors exist in the recorded data. The corrective action is to correct the errant data.
I
yi,f Enclosure 41 'yp To GCA 87-532 p, ,j - l 7 s q wm -
Attachment 4 y Page 39
,o
- of
.gyry ITEM NO. 17 g$
V Us 17 Description . Revise USAR
+
Commentary 1
. Chronolor. The investigations into the direct cause of a number of E
< ' h : CRTS problems has identified the need to revise and clarify the wording used in sections 3 and 8 of the USAR in a number of areas as follows:
0
' 1. Section 5.1.2.1.8.C.1.(b) [ Cable Tray and Bus Duct Supports]
The criteria for cable tray supports limits the . loading imposed on the tray to 50 pounds per linear foot. In fact, the 50 pounds per linear foot is a minimum figure, and supports have been designed which accept higher pounds per linear foot values. . This change is made for clarification:
i Existing Text "1. (b) Cable tray loading of 50 pounds per linear foot is used y
t j0 throughout regardless.of tray width or anticipated weight
{ of wire and cable. In no case does actual weight of s
wire, cable and tray exceed this figure."
,q Revigd Text
> "1. ,(b ) A minimum cable tray live loading of 50 pounds per linear
' ' foot is used throughout regardless of tray width or y anticipated weight of wire and cable."
. , ' \ ?q
/ , \ f, Section 8.2.2.11.H
< y This section provides criteria for the separation of redundant cables of s6fety circuits but is unclear because it mixes general criteria for all safety circuts with specific criteria for RPS and ESFAS circuits and does not cleariy indicate what is general criteria and its applicability. This change is made for clarification:
't Existino Text
}( ,
"H. The separation of redundant cables of the reactor protection system and safety features actuation system circuits is W i accomplished by spatial separation in accordance with the following criteria:"
I ! Revised Text i a ,
t ,, , , , ,
"H. The separation of redundant cables of safety systems is 1 ,o e h accomplished by spatial separation in accordance with the
'I , criteria given in this section. Specific criteria applicable
?, only to Reactor Protection System [RPS] and Engineered Safety
( Features Actuation System [ESFAS] cables is included" q
bi _ _ _ _ i_ c ___
Enclosure
- To GCA 87-532 Attechment 4 '.
Page 40 T" ITEM N0. 17 CONTINUED ,
- 3. Section 8.2.2.11.H.1 As a result of NCR S-6594 and LER 87-26, the District has performed a Safety Analysis, 50.59 log No.1020, which requires the followir.g change to the USAR text:
Existing Text L
"1. Separate cable tray conduit and penetration systems are ......"
... Class I instrumentation circuits are routed in rigid metal-conduits as explained in (2) below." ?
L Revised Text ,
"1. Separate raceway (cable tray, conduit and penetration) systeriis are ..."
... Class I instrumentation circuits are routed in metal raceway as explained in (2) below."
- 4. Section 8.2.2.11.H.2 As a result of NCR S-6594 and LER 87-26, the District has performed a ;
i Safety Analysis, 50.59 log No.1020, which requires the following change to the USAR text, because the Babcock & Wilcox design interface criteria for RPS and ESFAS cables requires separate " raceway" and does not specifically require separate " conduit."
Existfng Text 1
l "2. Reactor protection system and safety features actuation system l instrumentation each have their channels routed in separate l conduits and are physically separated from each other j throughout the plant."
l Revised Text l
"2. Reactor protection system and safety fesitures actuation system ',
instrumentation each have their channels routed in separate raceways and are physically separated from each other -
throughout the plant."
I l
l
p ;
-I F- ,, Enclosure h,
1 To GCA 87-532 h .<
Attachment' 4 4
-Page 41 !
, ;7
. ITEM NO. 17 CONTINUED .
5.:Section 8.2.2.11 H.5 As ~a- result of NCR:S-6562 and LER 87-26'an6 per the ' Safety Analysis, p '
50,59 log No.1002, the USAR will be changed as follows: q Existing Text .
"S. I Power and control circuits are not mixed with instrumentation !
circuits in'any raceway for 'any system,"
. 'I l
_ Revised Text {
l' S. Power and control circuits are not mixed with instrumentation circuits in .any raceway for any system unless an engineering analysis for acceptability is perfonned."
3
- 6. Section 8.2.2.11.H.9 Per the disposition of LER 87-24, the following change to the USAR has been committed to because both weight and ampacity considerations are different for. power and' control cables versus instrument cables. The ,
following text change.to USAR Section 8.2.2.11.H.9 is planned to provide {
clarification and also agreement with NEP 5204.22: )
i' Existing Text "9. The maximum percentage fill in redundant trays is 40 percent and wherever possible, it is kept at a much lower value."
Revised Text "9. The maximum fill in trays is' limited to prevent exceeding the cable ampacity rating in accordance with IPCEA No. P-46-426 .
and ICEA No. P-54-440, and the designed weight of cable on the _j tray supports." )
Cable tray fill limitations are typically imposed because of the following: J 0 All cable trays - Load bearing capacity of tray and supports O Power cable trays - Ampacity ratings of cables 4
um__-_ . - _ - _ _ _ _ . _ . _ . _ .
E' ..
L, >
Yi ,
EnclosurQ.
-:To GCA 87-532 I
I
- Attachment ,4 Page 42-
[L ITEM N0;L17 : j L CONTINUED L,-t .
The current status of'these-items at Rancho Seco are as follows:
Load 8 earing Capacity of-Cable Trays
- All.' tray weights [without regard to percent fill] have been checked '
- against the--50 pound per linear foot- USAR limit 'and will again- be '
Jchecked once more prior-to restart as described in .thel commentary to
'CRTS Action Item 2. An enhancement.is planned to the CRTS software to calculate cable tray weights for all; future' design changes, without
~
. regard:to fill level.-
Ampacity Rating of Cables--
The-ampacities for-600 volt 900C power. and control. cables routed through >
randomly filled cable trays are based on either the number of conductors
. [IPCEA No. P-46-426] or percent fill per:ICEA No. P-?4-440, typically 40% of al4" tray.
Scheduled USAR Revision
.These-changes are scheduled for inclusion in the next annual update.of the
. USAR in' July,1988. .
C t .i 1
j l
i
Enclosure To GCA 87-532 Attachment 4 Page 43 i l
ITEM N0. 18 DESCRIPTION Issue NEAP 4127.
COMMENTARY CHRON0 LOGY The identification of concerns regarding CRTS completeness and missing CRTS cards, followed by the further identification of cable installation ;
problems associated with LER's 85-16 and 86-10, led to the overall review of Rancho Seco cable installation procedures and practices, as described-in the Action. Plan and this report. Initial direct cause determination, confirmed by the preliminary root cause evaluations, has identified that the lack of a fonnal procedure, by which proposed changes to the CRTS data base are made and describing and controlling the issuance and return of cable and raceway construction cards, was a contributing factor in cable and raceway installation and documentation problems. It should be noted that no specific cabling problem appears to have been directly associated with or caused by the CRTS computer program itself, but that problems arose through not formalizing the procedure by which cable additions, modifications and deletions are made to the plant, and controlled and inventoried by the cable and raceway construction cards and the CRTS data base.
GENERIC IMPLICATIONS Lack of a formal procedure to control changes to the CRTS data base and hence control cable and raceway additions, modifications and deletions to the plant, was a factor in the following types of cable problems at Rancho Seco:
Cable Tray Overfills and Overweights Prior to June,1987 formal procedures for the engineering review and acceptance of overfilled cable trays did not exist. Rancho Seco cable tray supports are designed to support, as a minimum, a cable lording of 50lbs/ linear foot. The USAR specifies a cable tray fill limit of 40% so that the cable tray support design of 50lbs/ linear foot is not exceeded. In the past, undocumented engineering reviews were made when cable additions to cable trays exceeded the cable tray fill limit. Neither the informal checks nor the supervisory approvals were proceduralized and no documentation is available to show that such reviews have been made.
l l
l E
n
, i Enclosure y ,
To GCA 87-532
- Attachment 4 s Page 44 1
ITEM'NO. 18 CONTINUED 1
' Presently NEAP 4127~ " Cable and Raceway Tracking System" prevents the-issuance of DCN's to CRTS-related drawings-[E-1008,1010,1026,1027 and'1028] unless an error-free report can be produced when the data is entered into the' proposed data base. If a design error. is detected, then the DCN is returned to the originating engineer for resolution. Once an error-free report is produced,- the DCN is then submitted to the Electrical Supervising Engineer for approval.
Should the CRTS error report indicate an overfilled cable tray, the
~
lc DCN is returned._ for the _ engineering review and' evaluating of the cable tray's ircluded cables to verify that the cable tray support i
' design basis cable loading has not been exceeded.
CRTS Completeness ,
The " completeness" issue is discussed in the commentaries to CRTS.
Action Items 1, 2, 3 and 10. Concerns relate to whether or not CRTS
. recorded cable locations match "as-built", the resolution of CRTS data base discrepancies, cables not recorded in the CRTS data base and missing CRTS cards.
The formalization of CRTS procedures in NEAP 4127 provides the definitions and responsibilities sufficient to control future cable and raceway additions, modifications and deletions to the plant. l NEAP 4127 formalizes the flow of DCN's to the CRTS-related drawings, as well as the flow of the CRTS generated cable and raceway installation cards to ensure the retention of completed cards to ensure CRTS cable and raceway locations match the "as-built" and to ensure that CRTS data is entered without errors. By procedure, error reports are run on data to be entered into the proposed data base and_ again, once construction is complete, during the final processing of' completed cards, in order to. ensure that the proposed data, as well as the "as-built" data, is error free and reflects the actual plant configuration. l l
CAUSES Overall root cause evaluations, as well as the individual CRTs related root cause investigations have not yet been formally released.
CORRECTIVE ACTION Corrective action has been to issue NEAP 4127 " Cable and Raceway Tracking j System," issued June 15, 1987, to control changes to the CRTS data base i and control cable and raceway modifications to the plant. j l
l
g nw -
,- g. . q
,-, . 4,J. ,
, - j ;. A j
- -g M y ) -
/ 'g '
a
- j. c r Enclo'sure
@f p _.
' ~
fvy J.sq
'To GCA 87.-532-
$g ,
s LAttachment '4 <
"l
,f F , . Page 45 i , ,
.g; f^{, . ,
" ,- Q t p . ITEM NO. 19 ls! <k . . .. . . . . l
'7 s'" l DESCRIPTION?- . Provide, bases for acceptability of a: 95/95. level . of assurance , li regardingLcable routing.
, 1 e m i d .
C'OMMENTARY1 s
i Y ' '
, : CHRONOLOGY < , ,j
.. . , i The basis for 95/95 is given in the Sampling Plan [ Appendix (1)]'. _ Cablef )
A
. sampling started 51n' February,1987;and is scheduled.for completionfin - "
October,1987L Following a meeting with SMUD on May 6,.1987. andla4 '
subsequent telephone. conference 1 call on May:11, 19877 the NRC requested '
additional information. j q
SMUD. RESP'ONSE, "
'l
^ .
% The. additional 1nformation requested has been provided in. an appendix to '
l the commentary to.CRTS Action Item No.19 of-the. July Wire and Cable .,
y ,
. Program; Report. GCAL87-400,Ldated August 18.:1987, and therefore will.no: '
wm : longer be: included with.thisEcommentary, but will be referred to'as 1
Appendix 4 toL this' submittal..of,the Wire and Cable Program Report. . Once.a j i, joint agreement is established between the NRC and_SMUD the. Sampling Plan ]
will be: revised'to: reflect the ' agreement. The appendix has been prepared' !
by alSMUD consultant [Impell].and:
l
/
H:^
~
11.- Provides information'on established precedents.
.i l
' Provides additional information on the technical basis for the
~
i a 12. -
i T . Sampling Plan and provides a comparison between the _ Rancho Seco 1
-Sampling Plan.and Military Standard 105D'and related pians. !
4 t
1
-l y
m ,
m___m_.m___m_. m_ __ .u. ..-a- -- a
7 g y -- = -
S S 4
m
,h-
, ) ;,
i s - Enclosure -
g To GCA 87-532 ,
Jyg . tc >
4 A .. ' ,
> Attachments 4' l
? Page 46 4 44 <
/ .;
x c '
ITEM NO. 20' h.
r Resolve NRCzconcerns about possible. biasing of sample. .
' l-(1 DESCRIPTION:
-i
,e-
, COMMENTARY' ,
j m j.
CHRONOLOGY 1
~l "n. t Section93)(3),EvaluatifonProcess,of-theRanchoSecoSamplingPlan l:
L contains the following_ statement:
"If;a' deviation does exist between the CRTS database: routing and the
- ' ' "as-built" routing. the'results are first checked against existing CPR's.
or CON's-to determine'if the deviation has already been dispositioned. If.
this. problem has been dispositioned by a CPR or CON,,no defect for that loteexists."
The' question-was' raised, by Mr. Faust Rosa, at the May 6,11987 meeting as to whether the_ dispositioning of deviations, by CPR or CON,: introduced a
. bias.into the.' sampling.
~ SMUD RESPONSE-The_ response.to the concern is provided in this commentary. The process
- described in Section 9.1 (3).is essentially only a correction of minor.
bookkeeping' errors none of which impacted the cable route. Only seven
- cables had deviations which were dispositioned as described. All are-y detailed'herein and-none had deviations which affected the route. No. bias
- was introduced into the sampling-by Section 9.1 (3). This commentary will be'a'dded to the Sample Plan;in the next revision.
t lf w -- __. - _
,.7 l y, I n. '
L Encionre - 1 p .To GCA 87-532 l
. Attachment 4-Page 47 l
ITEM NO. 20 CONTINUED
, 1 f-
' TABLE 1 i ;
' List of Circuit Tracing Walkdown Cables with CONS or CPRs
<The following list of cables-are part of the CRTS circuit tracing sample
, cables and have CRTS problems identified as CONS (*) or CPRs(**).
Item . Cable Work Request Numbe2 CON or,CPR Designation
. 1~ ' IGlQ886AR 108063- CON-0118 CPR-0053
.t 2 :1M1A137 C 127745 CON-0001 3 1 PIA 06- D 126992 CON-1018-
.4 1RIC260BB 128755 CPR-0865 5 1RIC469CL' 127708 -CPR-0031 6 1R2IR2H C 127006 CPC-0534 CPR-0672 7 111B314 A.. , 127022 CPR-0866 1
?
- Conversion error reports (CONS) were generated for equipment, l raceway, and cable problems identified from the June, 1980 computer conversion error reports prepared by SMUD's contractor, Control Data !
Corporation, when Bechtel Power Corporation's EE-553 data base was converted to.the present CRTS data. base.
- CRTS Problem Reports (CPRs) were generated for equipment, raceway,
~ and cable problems identified after the June 1980 conversion.
4 The following describes the problems and resolutions stated on the associated ;
CONS /CPRS and their impact on the circuit tracing walkdown effort. i
)
_ _ - - _ - _ - - . - - - - - -- _ -- -----_ -- - - I
- g. ,. - --
3 y ;
Qy),?
fy ' "
L.-
% ~p l r J :' <
3
. Encl osure '-
- j,l - . -To'GCA 87-532 ,
< ,, n, e l . :n it '. Attachment "4
[
ai- e, ,
Page 48 g s -
't 4 t
T i# <
.E , ITEM NO. 20 CONTINUED r -
6 ?l Table'l.(continued)'
'i .
' ITEM 1-Cable: 1GlQ886AR-on CON-0118 and CPR-0053 w
- Problems:: CON-0118 states that' the'CRTS raceway vias do not:
A match Bechtel's EE-553 cable" routing..
C'P R-0053 states that~ the construction- card's first and.last vias'(" red") do not match CRTS first and lastvias'(" white").
- Resolutions:' ' CON-0118 -- Junction box numbers were removed from CRTS. vias and were confirmed by walkdown.
7 CPR-0053 - ' Inspection verified the cable is painted
, .g .with " red." DC0 has been issued to correct CRTS.
,Walkdown' Impact:' .None on cable routing 4
ITEM 2 Cable: IM1A137 C on CON-0001 Problem:' CON-0001 states that CRTS vias show cable. tray L43V36 connecting.to L39BN5, but CRTS raceway connections do not show them connecting.
w M ? Resolution:' . CON-0001 -- CRTS Revision Level 1372, 02/16/87, racew6y connections show Tray L43V36 connecting to L39BNS.
'Walkdown Impact: None on cable routing i
, 4 4
i v i i
i.,,
w-.--.-...._..a -_
py -
m o .- , ,
, o
+ r
)
_! r,_,
Enclosure E To GCA 87-532 h
L 4-Attachment 4 L .
,,-Page 49 i
ITEM NO. 20-H ,
CONTINUED
. < Table 1 (continued)'
ITEM-3 Cable: IP1A06 D on' CON-1018
- Problem: CON-1018 states that "from" termination of cable does not match equipment I.D. schedules. '
Resolution: ' CON-1018 - "From" termination is a section of a panel, Panel'is listed in equipment I.D. schedule.
-Walkdown Impact: ' None on cable routing
- ITEM 4 Cable: 1RIC260BB on CPR-0865 Problem: ' CPR-0865 states that CRTS shows the cable has a deleted status and-removal of the cable is not verified.
Resolution: CPR-0865 -- Inspection verified the cable is being
- spared and' has been retagged to 181PA0101.
Walkdown Impact: . Cable is deleted. New sample cable selected.
~
ITEM 5 Cable: 1RIC469CL on CPR-0031 Problem: CPR-0031 states that the pull card is not signed by QC.
Resolution: NCR was issued and when dispositioned, the pull card will be signed by QC after inspection. !
l Walkdown Impact: None on cable routing ]
4 1
Enclosure To GCA 87-532 L Attachment 4
[
Page 50 ITEM NO. 20 CONTINUED Table 1 (continued)
' ITEM'6 Cable: IR2IR2H C on CPR-0534 and CPR-0672 i I
Problems: CPR-0634 states that the cable is routed in Class 2 l overfilled tray.
CPR-0672 states that the construction card has not been received and that the number of conductors does not match design drawings. i 1
Resolutions: CPR-0534 -- Cables in overfilled tray were j analyzed.-
CPR-0672 -- Resolution of Non-Class 1 problem on unsigned construction cards is not completed.
Walkdown Impact: None on cable routing ITEM 7 Cable: 111B314 A on CPR-0866 Problem: CPR-0866 states that CRTS shows the cable has a deleted status and removal of the cable is not verified.
Resolution: Inspection was performed and confinned that the cable does not exist.
Walkdown Impact: Cable is deleted. New sample cable is j selected. I, I
l l
l l
l
- -_________. - ]
gw y ...
, 4 ,,
, 3 ,, ,
r qn .
L p' jju,4 i l w ;;,-
i S'r ; e /.L j ,..
.y)ic- ts
~~
W- ' Enclosure "e ' ..
.To GCA 87-532 4-
- ' ; i '
id .3 ,
3.'
s
. Attachment 4 ir Page 51 j1 ,
, j
' ITEM NO. 21 i '
{ ?
. DESCRIPTION , . Provide NRC with location of'c'able pull cards.
- COMMENTARY U ' ,,f . '.y( : .
3
. Refer. to' commentary to.CRTS Action Item 3.
" ?"E > l T
t ff!Y' 4 w:
f
-l i >
3 1
'r i ,
. .. ' ljl .!
L ,
I t
,? f' .*
e- . ,,
f'
- fu f
I, s
1 s
4 e
'--.-__.mm_._ .___ __ _ _ __ _ _
y[ ' _'- - - .
j3.
i * , '
' ~~
I
.bi'; ' -b! ,.'$
, y, ' . 'h ', ,
p_
4 y . ;
m d
';i : . ;: i l
n ,
. Enclosure .
. ,a ' ? '.
To GCA.'87-532' -l 00:- '
.1
.. Attachmerit' 4
'/ g .
Pace.52 av ITEM-NO.-22 ,
j
, . s ... 1, -
~
- DESCRIPTION L' Provide NRC with future plans for. cable' pull' card's.
. .o , ,
V 4 ', j W . COMMENTARY d
- c. n. ,.
~ ..
1 Refer commentary to CRTS: Action Item 3; !
p.
$, ?. '. > - ,
i.~ h i
G r.
f
- e l is{r .
F .'
.l: g 1
H l
)
1, , .
i
.g y
t i
l 1-l i, l
r
,m I
4 -
"g Enclosure-
% To GCA 87-532-Attachment 4 y3 Page 53 ITEM.NO. 23 l DESCRI'PTION' Redundant cabling in the same fire area (LER 86-10 and 87-13).
, COMMENTARY K ,
CHRON0 LOGY
-Refer to; Root.Cause Investigation 86-10.
t GENERIC: IMPLICATIONS-LER's 86-10 and 87-13 identified significant concerns with Rancho Seco cable configuration control. LER 86-10 identified seven safety related instrumentation: cables in Fire Area 17 that were not rerouted into fire wrapped? conduit as ' required by CRTS. LER 87-13. identified seven safety related instrumentation cables that were not moved from Fire Area 36 to Fire Area 31 as required by CRTS. In both cases the cable rerouting was to have,been performed under ECN A-4942, and in fact the subject cables were correctly routed per; the original issue of..ECN A-4942. However, the routing 'of the cables was revised several times ~after the initial issue of ECN A-4942 and the failure to subsequently reroute the cables resulted i
?- c in LER's 86-10 and 87-13. 'In-addition to the safe shutdown / Appendix."R" concerns that arose as a' result of the incorrectly routed cables, additional concerns identified by. preliminary root cause-investigations
. include that of adequate control of CRTS cable. and raceway installation
. cards [See commentary to CRTS ActionLItem 18] and the failure of the Electrical QC inspectors to verify proper locat'fon and routing of the subject cables [ Notice of Violation 50-312/87-21/-01).
CAUSES.
Refer to Root Cause Investigation 86-10.
CORRECTIVE ACTIONS
-In response to LER 86-10, Rancho Seco began an inspection program 6f safety related cables to establish a level of confiden::e in the cable locations, as well as the CRTS data base. Based on the analysis of the misrouted cables in LER 86-10, and the lack of identified cable routing problems in the original plant cable population, the decision was made to only. sample those safety related cables installed after commercial operation in 1975 [ Justification provided in commentary to CRTS Action Item 7]. As described in the Sampling Plan [ Appendix 1], the post-commercial foperation safety related cables have been divided into four sample populations and the objective has been to demonstrate with a 95% level of confidence that at least 95% of the sampled population is
- correctly installed in the plant per CRTS. Cable inspection as part of l' the Sampling Plan, identified the seven additional cable misroutes, described in LER 87-13, and prompted the 100% inspection of the lot 4 sample population, which is complete with no additional major defects.
_ z---..__ _
n>n%
+ ,
o >1 j
af -
) '
,s[ ~[ , ,
~
7;; J
~
, Enclosure c, -
To GCA 87-532L y,
Attachment 4.
Page 54 .i Yp _-
1
- ITEM NO.:23' 1 CONTINUED i y , .
..- ., ,. . . .6 . !
' Additional cable misroutes 'were identified 'as described in' 0DR's 87-604- ;
L and 87-723 and .have. required the.100% inspection of the' Lot.1: sample- 1
- e. :r popul,ationi currently in progress. . Cable. rerouting for those misrouted -
- cables identified.by_LER,86-10 was performed by ECN R-07.65 and
- is- ,
construction complete. l Cable rerouting for those misrouted cables j
identified by LER 87-26'was: performed by work request-and 1s also l complete. Misrouted cables l identified by 0DR'sL87-604 and ,87-723 w111: be . !!
'c ' corrected by ECN's R 1785 and'R-1786,1ssued on-July: 23,1987 and' June
' 26,(1987 respectively.: Construction completion for R-1785 and -R-1786 is-
. forecast for early September. . Additional-corrective action.has been to-include'in the Modification Procedure / Inspection Standard MP/IS 307, !
" Cable Installation," . requirements to ensure that when installing cable, i ithat the design documents are the-latest' revision, and that the' cable routing information on the = E-1010: series drawing matches. that on the applicable; cable installation card. Further requirements have been ;
included:in MP/IS 307' by- Procedure Change Notice, in' order to clarify the-requirements- for witnessing cable- pulls, as follows:
" Verify the cable is installed in the raceway specified by the
- applicable E-1010 series' drawing. Verification shall consist of
' witnessing the installation of the cable."
i l
e
=___=_
,)-
.,;. ./
Enclosure
-To GCA 87-532
. Attachment '4 Page 55
- ;l
- ' ) -'s . 1 ITEM NO. 24 DESCRIPTION
- Provide description..of the installation; procedures and practices.used at' Rancho Seco for the original cable' population
.of.14,000 cables.'
t' COMMENTARY.
CHRONOLOGY
. Refer to commentary to CRTS Action Ites No. 7.
'I a
I I
i t
-_,.-._.--___.____.-___.-._--.__-----J
m , y' > ,
m,
- 2 -
+--
, 4f < , ,
p y' ..
4
- p N
- ' V Enclosure
~ ' "- '
< To GCA 87-532 Attachment 4 Page 56 ,
1 ITEM NO. 25
'b DESCRIPTION Provide description.of the installation procedures and practices used at Rancho Seco for the.9,000 cables added after
.comercial operation [1975-86].
> COMMENTARY-CHRONOLOGY >
-.To be.provided 'in the' October Wire and-Cable Program Report. ;
L I
.1 4
)
I c i i
i
' i --
I
)
f 1
l )
! l t
.j -
l l j
a
-m .
ill 'I' -
,{- .3
- ci
- \
Enclosure To GCA.87-532 .
Attachment 4 Page 57-
- . p
' ITEM N0. 26
.. DESCRIPTION: Provide 1 description of the' events .'and circumstances leading to.
J the' misrouting of cable described :in LER's 85-16, 86-10, 87-13.'
.and,87-26..
'% Y LCOMMENTARY.
CHRON0LOGI'-
e
, To be provided'in the Octobor Wire and Cable. Program Report.
1 s
i i
1 l
]
l l
J
.p, r
l- 1
-____-___.-_-_______J
,e v'5,:
i
[,7,$
1 y-l e
Enclosu're
..n T.' m -
.To GCA 87-532 y.1',,
Attachment 4 d '- .
<Page 58
. ITEM NO. 27 DESCRIPTION' : Provide. description of the events' a'nd circumstances leading to i' .the: discrepancies discovered between' the "as-built" cable
' routes and the. routes ~ recorded in CRTS. ,
- COMMENTARY L CHRON0 LOGY To be provided in the Octob'er: Wire' an'd Cable Program Report.
i.
- a 1-
_.r d I
a 1
l b
il q l
i
, I
}
q., g/ - -
, , 1s l'
3 4 ,' + e4, , ,
, ,o 6 , ,
Enclosure'-
' To'GCA 87-532, fM , 1-o y* ' "
lAttachmentL'4'
' ' ^
Page 59-t> n j
'I
- ,' ~
ITEM NO.'28 L
Description - , ProvideL the. bases for acceptability of 'a 95/95 leve15 of-
_ assurance regard i ng cable routin [ Compared with other.
accepted homogenous ' populations]g.-
- ' l Commentary! . .
The basis for' acceptability of a'95/95' level of assurance-regarding: cable routing' rests on two arguments:
, 1
.1) , Prior uself 95/95 acceptance criteria in Nuclear Power -
m . Plant Sampling Applications.
, 2) _
Application'of. 95/95 acceptance criteria to cable routings.-
s The response concerning prior acceptance of._95/95 is given in
.the response to.CRTS Action Item 19 and is complete.
' Application Of 95/95 Acceptance' CriteriaoT' Cable Routh
~
- The confidence level . established lby the 95/95 acceptarce criteria is the.
conditional ' probability that the percentage.of major defects in the total
- ' population is less than'or equal to five percent.
Two populations [ Lots-1 and 4]'have been given 100% inspections. The acceptance 'y s criteriatis applied to Lots 2 and 3 both of which have been sampled with the following results:,
i Lot 2 Lot 3 j Population Size: 1702- 190 49
~
Sample Size: ' 91 Major Defects: 0 0 Is b
i
- _- ._- _ _ ___ _____a
p3:
N' 3 m - Encl osure.'
? '
'To.'GCA 87-532
- 3. - %
Attachment-'4E
, Page 60 u .
i '
ITEM NO. 28
- CONTINUED.
- Statistical inferences using the likelihood Density Function Method are:
l L'o t ' 2. Lot 3 .
~ Maximum likelihood estimate.
, .of the percentage of improp-L .crly routed circuits: 0.0% 0.0%
- q
Conclusion:
With 95.2% confidence With'95.6% confidence, it can be asserted that it can be asserted:that 96.8% or more 'of the ~ 95.2% or more of the circuits are properly
~
circuits are properly routed. routed.-
[ Notes " Confidence"L is: the conditional probability that the^ population from which the sample was drawn contains no fewer than 'X' percent acceptable, items, given the. evidence available from the sample.]
Statistical ' inferences using Acceptance Sampling Methodology are:-
Lot 2 Lot 3 Probility of acceptance if the incoming quality is:
greaterthan5% discrepant.(-0.008 s<.0.047
Conclusion:
.With 95.1%' confidence,. With 95.3% confidence, it can be asserted that it can be asserted that 96.8% of the circuits 94.7% of the circuits are properly routed, are properly routed.
[ Note: " Confidence".is the conditional probability of rejecting a lot containing 'X' percent discrepant items, given that a lot of that quality has been submitted.]
4 im_.__.___._ _ _
pm - ,
s lU ,
3 Enclosure l
To GCA 87-532
' Attachment 4 Page 61-
.c.'
' ITEM NO. 28
-CONTINUED The establishment of Lot 3 separately from Lot 2 was done in an attempt to- t establish whether the cards with " questionable" signatures constituted a special class ~with a common problem. With 25.8 percent of Lot 3 inspected this is
.c-clearly not the case and the." questionable" signatures have no significance.
Therefore Lots 2 and 3 can-be examined statistically by combining the total and- j
. sampled populations together. This gives a population:
LOT 2A-1 Population Size: 1892 Sample Size: 140 Including the three additional circuits in Lot 3 and one in Lot 1 [which were
-not taken credit for] gives another population:
LOT 2B l
Population Size: 1892 'i Sample Size 144
-This lots. allows Thesethe examination figures are: of the statistical inferences for the combined Statistical inferences using the Likelihood Density Function Method are:
Lot 2A Lot 28 Maximum likelihood. estimate of the percentage of improp-erly routed circuits: 0.0% 0.0%
Conclusion:
With 95.27% confidence With 95.31% confidence, it can be asserted that it can be asserted that 97.99% or more of the 98.04% or more of the circuits are properly circuits are properly routed. routed.
[ Note: " Confidence" is the conditional probability that the population from which the sample was drawn contains no fewer than 'X' percent acceptable items, given the evidence available from the sample.]
i i
l i
p ( 5'
~~
~ 'Q ,
e
- q ; '
m ~,
i- ~ Enclosure.
, e ,
' ' > To GCA 87-532; L . i. u Attachment 4
i g Page 62 Q,
,;n ;,r ';
ITEM NO. '
CONTINUED
. . . - . . . , d Statistical inferences using: Acceptance Sampling Methodo1Gy 6,e7 H I
Lot 2 jajg,3 Probility of' acceptance
-if'the incoming quality is.. 9 7 ,
- greater l.than 5% discrepant. 4 5.44 x 10 4 0.00048
.With 95.2% confidence, With 95.2% confidence,
Conclusion:
it can be asserted that it can be asserted that 97.9% of the circuits 98.0% of the circuits are properly routed. are properly routed.
[ Note:: " Confidence" is the conditiona1' probability of rejecting a lot
- 'containing X' percent discrepant items, given that a lot of that quality
. .hasbeen-submitted.]
A're11 ability level of 98% for the combined population of 1892 would indicate the possibility of -38,.or fewer, major defects.- This possibility has to be
-evaluated against the evidence. produced by the inspections and other sources:
'19 major defects were-found; 7 in lot #4 and 12 in lot #1. These cefects fall into 3 incidents as follows:
- 1. Seven [7] major defects in lot 4 were all .in one incident and are k documented in LER 87-13. The seven cables were to have been moved by ECN A-4942 from Fire Area 36 to Fire Area 31, but were. left in place.
' Associated with'this incident are the seven additional cables that were to have been rerouted into fire wrapped conduit.in Fire Area 17 by ECN l A-4942, but were also left in place. - The Fire Area 17 cables were !
identified by LER 86-10. prior to the ' start of the Sampling Program, and ]
are not counted as major defects. The misrouted cables could have caused 1 a loss of redundancy if a fire had occurred in either Fire Area 17 or 36. 1 The direct cause of the cable misrouting has been identified as personnel !
error, j i
7 I
i
.3 .
ml>.
g ,
v i
'r R y:; ,
t -
0 LJ* '
Enclosure p; , #
To GCA 87-532 ,
e '
Attachment 4 .,
J , s Page 63 L.; ,
S 2.. : Elevens [11] Major Defects were found to have been. caused in aisecond-y incident?in 1981 'when a. power. and control tray was re-tagged as an-0
, .l instrument' tray but without the eleven power and control cables' being.
% removed. The. direct cause appears to be design error.
c.
s 3. - One [1] Major Defect was caused'in.1984 ' when-a Class 1 conduit stopped ,
short of a '1oor blockout causing the cable installer to complete the R
.last four feet of.-the. route in a.Non-Class I cable tray.
,, . Evidence - Other Than Inspections
,, J An examination of all sources [such as.LERs, DDRs.N ' CRs] for major defects.in s (Populations. l.2,3 and' 4 has found no' major defects to add to total of:19 found J
lby the . inspections other than_ the 7 major defects reported in LER 86-10 which are part of the same incident reported in LER 87-13 and discussed as part of incident #1.
The major defectsIfound are therefore limited to the three incidents i idescribed. This fact is ~ strong evidence to suggest that there was no systematic breakdown in the design and/or-installation process for cables but.
' rather a limited number.-[3]-of specific. incidents. This is taken as an indication that' the real number of major defects, which would be found by a
- 100% inspection, is likely to be less than the statistically inferred totals.
. Correlation between earlier precedents [ established by NRC] for acceptance of 95/95 sampling of safety related components [such as structural steel welds and concrete expension bolts] is yiewed as follows:
-Given a possible discrepant [ major defect] population of thirty-six the following must occur coincidentally to impact plant safety.
- 1) A major defect or defects have to exist in safety related '
components.
2)- The major defect or defects have to involve a loss of redundancy in safety system. l
- 3) An incident or accident has to cause a coincident failure in '
redundant ~ safety systems.
I
\
~
Enclosure To GCA 87-532 Attachment 4 Page 64 l
L ' ITEM NO. 28 CONTINUED-l The basis of.the NRC acceptance of 95/95 sampling for structural steel weld inspections is assumed to be the low' probability of coincident weld failure in-supports of' redundant systems. The following must occur to cause a loss of redundancy:
- 1. 'A' defective' weld must exist in the welded steel supporting a safety system.
- 2. A defective weld must also exist in the welded steel supporting the redundant safety system.-
- 3. An incident or accident must cause stresses resulting ir, weld failures in welded supeorts for redundant safety systems.
- 4. The failures must be sufficiently severe to impair safety function
[1a both sets of equipment] below'an acceptable level.
The basis of the NRC acceptance of 95/95 sampling for concrete expansion bolts is assumed to be the low probability of coincident failures in redundant safety related equipment. The following must occur to cause a lost'of redundancy:
- 1. Defects must exist in bolts holding down safety related equipment.
- 2. Defects must also exist in bolts holding down redundant safety related equipment.
- 3. An incident or accident must cause stresses resulting in bolt failures in both sets of equipment.
- 4. The failures must be sufficiently severe to impair safety function
[in both sets of equipment] below an acceptable level.
For major defects in the cable routes of safety related cables the possibility of coincident failures in redundant safety systems is more complex. The types of major defects identified at Rancho Seco include:
A. Redundant safety cables in the same fire area [14 cables in 1 incident].
B. Lack of acceptable separation between Class I cables and non-Class I cables [2 cables in 1 incident].
C. Lack of acceptable separation between Class 1 instrument cables and Class 1 power / control cables [42 cables in 6 incidents].
% L;;" -
b Nf? ';
,'},
thyh@ NL r.
~ '
Enclosure) < ' '
3(9tM@a Ny y " ,
. ; ToGCA;87-532g-x ~ , , _
Am iAttachment -4'-
f/MI, ;.
r, Page 65- h tt .
7
,i3 .
Y '
h
. ITEM NO.'28 1 s
CONTINUED' l i
.'8 I
( A,l B$,rendTC defects 1have been identified:in the: Rancho Seco Lcable populations-
'andsare' considered viable. iPossible scenarios which could -impact? plant safety ' ]
V' e Lare: 1 /, 'l ,,'4
. 4..
m .i 6
_,~
4
-r t
.(. .
1
! Major Defect B An electrical overcurrent' condition in ai NonjClass" " c j 2.
4 1 cable combined with a single failure in an overcurrentPdevice. t en This cculd cause a(condition'in which a cable: failure /could impact.. ]i y, -)
~
f... g* la Class.1: cable [ lacking. adequate separation)-resulting in a los j of safety, function.: -/ f q
- 3. 1 Major. Defect C. An' electrical transient-in 4 power cable caudjEg, a j 4 : spurious contro11or indication signal 1p an instrument cable - :? : '
i 1
+-L[lackjngladequateseparation]. p 1 ..
q -.y4q )
i ' w, r. 4 Scenario 1 postulates a single major defect 1resulting .in a. loss toff L . . f' t. }
credundancy. :This would" appear to, indicate!the need to. reduce s the:po'sibility- .j
- s of major defects to;a minimum. However,'for a single l incident or accident 6
to '
. cause- a loss of, redundancy the following must occur:
t s'
'7 Major Defect A '
n L 1. Redundant safety cables must exist in the same fire area.[ ', ,
s~~ ..
- 2. L A' fire. must be initiated..-
w n <
- 3. The' fiqe detectio6/ prevention system must' fail.
~4. - The fire mushcause a T loss of safety function in both IEEE 383 qualified
[ff re. retardant) cables.
5.. Neithe'r loss of safety function is to a '" fail-safe" condition. )
,, y Major Defect B Q
1 w .
?~ 1.. ' A lack of acceptable separation must exist between a Class I cable and a W Non-Class 1 cable.
2.. A failure must' occur in the Non-Class I circuit conductor or component. y u 3. l A failure must' occur in a Non-Class 1 circuit protective device.
4 .' The' effects of the two failures must be sufficiently severe to cause ai, failure in an adjacent Class 1 cable. \
- 5. The Class 1 failure is not to a " fail-safe" condition.
11 6.- . A simultaneous failure must occur.in a redundant class 1 circuit.
M /? -
lh j ,
e ... x y - f .
3 y
L
. t; o j u#
6 y ,
L
' ?
ic
- "" Enclosure
? -
"j "
, ,: To GCA 87-532 t
Y Attachment 4 Page 66
- ITEM NO. 28 CONTINUED S' '
N> Major Defect C c .I.
- 1. A lack of separation must exist between a Class l' instrument cable and a
{r- ,
power or control cable.
- 2. An electrical transient must occur in the power or control cable causing a " spike" [ electromagnetic induction] in the instrument cable.
x
- 3. Tne magnitude of the induced " spike" in the Class 1 instrument cable
& must be sufficient to initiate a spurious action or indication in the instrument circuit.
!{-
- 4. A simultaneous failure must occur in a redundant instrument circuit.
! From the evidence and discussions provided it would appear that:
The number of major defects in Lot 2 and Lot 3 cable routes, that would be found by a 100% inspection is likely to be less than thirty-eight
[38].
- The likelihood of major defects in cable routes causing a loss of redundancy in safety systems is r,ot higher than the likelihood for welds ,
and concrete expansion bolts sampled to the same level, j Conclusion The confidence / reliability levels for Lot 2 and Lot 3 are as stated above. To closely correlate the sample results from three diverse populations appears impractical. However, based on the logic presented in this commentary, the acceptance of 95/95 for sampling homogeneous populations is considered to be equally valid for cable routes as it is for weld inspections and inspections
, of concrete expansion bolts.
I I
_- -