ML20237L717

Forwards Comments on Plant Revised Cable Test Program. Industry Experience Adequate to Refute TVA Claims.Nrc Agreement W/Test Program Would Establish Lower than Necessary Stds as Precedents for Industry

ML20237L717
Person / Time
Site:	Sequoyah
Issue date:	08/21/1987
From:	Hicks D AFFILIATION NOT ASSIGNED
To:	James Keppler NRC OFFICE OF SPECIAL PROJECTS
References
NUDOCS 8708280222
Download: ML20237L717 (10)

Text

.]

t-e.

}

6621 Wachese Lane

. Knoxville, Tennnessee 37912 August 21, 1987 iir. James Keppler, Director Office of Special Projects U. S. Nuclear Regulatory Commission i

i East West Towers West W ashington, D. C. 20555 Lear Mr. Keppler:

Reference:

Letter from R. Gridley to NRC, "SEQUOYAH NUCLEAR PLANT (SQN) UNITS 1 AND 2 - REVISED TEST PROGRAM,"

dated July 31, 1987.

Per requests from you and Mr. B. D. Liaw, I am providing the enclosed comments on the referenced test program.

I do not believe the NRC should accept.the program as submitted.

There is adequate industry experience to refute a number of TVA's' claims.

To agree with TVA's test program, the NRC would be establishing lower than necessary standards as precedents for the industry.

Sincerely, kall v k.00 Dallas R. Hicks Enclosure cc:

(1) Dr. Henry Myers Committee on Interior and Insular Affairs (2) Mr. Peter Stockton Subcommittee on Oversight and Investigations Committee on Energy and Commerce 1

i DR A

1 e

\\\\

l

i COMMENTS ON TVA'S PROPOSED CABLE TEST PROGRAM, DATED JULY 31, 1987

REFERENCES:

1. NRC Letter, B. J. Youngblood to S. A. White, " Evaluation of Sequoyah Units 1 and 2 Cable pulling and Bend Radii Concerns,"

dated March 9, 1987, and the enclosed Technical Evaluation Report (TER) by Franklin Research Center, dated February 19, 1987.

2. Meeting between NRC and TVA in Bethesda concerning cable j

testing on July 13, 1987, and the resulting transcript.

3. TVA letter, R. Gridley to NRC, "SEQUOYAH NUCLEAR PLANT (SQN)

UNITS 1 AND 2 - REVISED TEST PROGRAM," dated July 31, 1987.

j l

1 COMMENTS ON REFERENCE 3 ARE AS FOLLOWS:

1. In the second paragraph of page 2 of the letter, TVA stated:

"In particular, it was apparent that the test voltages utilized were higher than necessary to verify the integrity of the cable.

In addition, this testing, which was performed without the introduction of water, was able to detect damage that was insignificant when compared with the type of damage postulated in the technical evaluation report (TER) for pullbys and jamming.

Previously, it had been inferred that only in the presence of water."y de high potential testing such damage could be detected b I do not agree that the test voltages were higher than necessary i

to verify the integrity of the cable.

It just happens that the insulation was already degraded to a level such that lower level of voltages could have possibly detected the damage.

TVA's statements concerning the voltage level and the lack of use of water are misleading and are apparent attempts to justify a position not to use sufficiently high voltages and water immersion of cables as has been recognized as a need for qualification and required by the industry.

The fact that a cable insulation fails at a lower voltage and without water is absolutely no reason or justification to lower the voltage and to eliminate water immersion.

Other cable insulations may be unacceptable in integrity of insulation capability but at higher integrity than that of the subject failed cables.

They would be detected by the conditions of higher voltage and water immersion.

2. In the third paragraph of page 2 of the letter, TVA stated:

"As a result of the above, TVA concluded that continued testing, conducted at the original parameters, could potentially impact plant safety and, furthermore, could result

COMMENTS ON TVA'S PROPOSED CABLE TEST PROGRAM Page 2 in the replacement of acceptable cable with no increase in plant safety."

This statement is erroneous and misleading.

Cables in the 600 volt class that are in good condition should withstand 20,000 volts or higher.

This is recognized by the industry and is included in IEEE Standards 141 and 241, both being recommended practice manuals produced by IEEE.

TVA tried to make a case in the July 13, 1987, meeting in Bethesda that degradation of cable insulation after manufacture may occur in shipping, handling, and in the instal}ation process, as well as in aging.

While this is true, the degradation should not be so great that slightl that half (10,800 volts) the above level (20,000+ volts) y more could not be withstood.

It is well understood that the TVA process for handling and installing cabling was extremely deficient in many l

areas such as follows:

receipt and inspection, storage, handling, installation, testing, and quality assurance.

Engineering was deficient and there was a general lack of engineering oversight for the installation, check-out, and handling and storage of cabling.

One could write extensively about the abuses and mishandling of cabling at TVA.

For brevity, one can conclude that the process was flawed in virtually every area and any subsequent claims by TVA to the contrary are misleading.

]

3. In the last paragraph of the letter, TVA stated:

"In addition to the program described herein, a cable test program will be established that will be consistent with Inspection and Enforcement (IE) Notice 86-49.

The program will also address low-voltage cables.

The purpose will be to demonstrate margins above the system design basis.

This program will be described to NRC within six months after restart of SQN unit 2 and will be implemented by the end of the SQN unit 2 cycle 4 refueling outage."

IE Notice 86-49 does not state much and does not define specific requirements.

Its intended compliance by TVA means little to the resolution of the cable problems, even though TVA has made a big deal here and in the July 13 meeting that they will comply with I

this notice.

There is a major problem included in TVA's assumptions for getting NRC's approval of a promise to develop a test program in the future.

The NRC should not be approving a program that is not yet developed by TVA.

Restart should not be allowed on such a basis.

l

4. TVA's statements in Item 1 of Enclosure 1 to the letter are misleading and do not show conservatism.

One cannot make a case for conservatism on an isolated item when the overall process was flawed as discussed in Item 2 above.

l

COMMENTS ON TVA'S PROPOSED CABLE TEST PROGRAM Page 3

5. In Item 2 of Enclosure 1 to the letter, TVA stated:

"Recent interviews of electricians who had actually performed the cable installation at Sequoyah, conducted by the NRC/ Consultants, indicated a thorough understanding of the cable installation process and the relevant concerns.

These interviews substantiated conformance to proper construction practices used throughout the industry and utilization of the engineering approved installation procedures and specification and confirmed the presence of a Quality Control Inspector on all Class 1E cable pulls.

In addition, the close working relationship between construction and engineering was outlined including the evaluation made before each Class 1E pull to determine the best method of installation, which included determining the direction of the pull and the need for manual assistance at pull points to reduce tensions.

The testimony in these interviews was contrar to Watts Bar Nuclear Plant employee concerns in this area.y' These statements raise more questions.

It is recommended that the NRC obtain the documentation on these interviews and investigate the degree of accuracy therein.

Considering the overwhelming problems resulting from poor practices discussed in Item 2 above, one can only conclude that the above statements are misleading.

People can have a thorough understanding during or after the fact of performing tasks, but still do sloppy and unacceptable work.

The measure of acceptability is the end product, and in this case, it is unacceptable.

6. In Item 3 of the Enclosure to the letter, TVA begins to state their proposed position to use a test voltage based on " specific minimum environmentally qualified insulation thickness for the vcitage rating and insulation type and manufacturer."

This position is weak and it does nothing to support TVA's seeking to establish an adequate margin.

In fact, when one uses the minimum of anything, there is no existence of margin.

This position does not provide confidence that adequate margins will exist and it is not one that should be the foundation for setting an industry precedent.

Further, the NRC staff assumes, from TVA's claims, that " minimum environmentally qualified voltage" is acceptable because it was the basis for Sequoyah's Operating License.

I disagree, and I further challenge the NRC and TVA to prove this.

7. In Item 3 of Enclosure 1 to the letter, TVA stated:

"As such, use of the f actory test voltage at this stage in the I

life of SQN cables may damage cables that are otherwise acceptable and inhibit a root cause determination of any test failures."

This position has no basis.

It entirely misses the reason for testing.

Known damage exists at TVA and has been verified by testing, and the very reason for testing is to find the extent of problems and replace the defective cabling, thus obtaining a high

COMMENTS ON TVA'S PROPOSED CABLE TEST PROGRAM Page 4 confidence level for the quality of installed cabling and its ability to permit the plant to operate and shutdown safely.

Any cabling that cannot meet the tests should not be left in the plant, but should be replaced.

8. In Enclosure 1 of the letter and during the meeting specified in Reference 2, TVA and its consultants quoted a number of IEEE standards.

Although a senior member of IEEE and several of its societies, I do not believe that all of these standards are sufficient by themselves; for example, they inadequately address 600 volt cabling.

Referencing these standards and stating an intent in meeting them means little and does not solve the problems at Sequoyah.

The NRC should carefully review the IEEE l

and ICEA standards for cabling and should note the voltages in j

ICEA S-68-516, Revision 7, Table 3-1 (IPCEA S-68-516, Enclosed).

i

9. In Enclosure 2 of the letter, TVA refers to the use of PVC cable insulation.

Why has the NRC not required TVA to replace the PVC at SQN, especially ir view of the disastrous l

results from the Browns Ferry fire and all of the subsequent PVC restrictions?

How can the NRC continue ~to allow plants to contain PVC without having replacement programs and schedules in place to replace all PVC eventually?

10. In Enclosure 2 of the letter, TVA explains its cable selection / sampling criteria.

More time has been spent on this than would have been taken to test all of the cabling that is subject to damage.

11. In Enclosure 2 of the letter and in the meeting specified in Reference 2, TVA tries to make a case for not testing all cables i

in water.

This is contrary to commitments described to me by Mr.

Raughley and Dr. Fox in a meeting in Knoxville on June 23, 1987.

TVA now states that they will wet the cables on a case-by-case basis, but "It is not intended or expected that the cables will remain submersed throughout the test."

To wet cables without keeping them immersed makes no sense and will have no intended immersion effect.

Either TVA tests the cables wet (immersed) or dry.

There is no middle ground that could be remotely justified on this issue.

Yes, it was a ridiculous suggestion to wet test cables in all areas, but this latter proposal is even more ridiculous.

The NRC should require wet immersion testing to the degree necessary to resolve the concerns and disallow the TVA approach.

One solution would be to remove section(s) of cabling and conduit (all intact after having been cut on both ends).

Then take it outside the plant, seal one end, fill with water, and high-pot test it.

Compare this with the results of dry testing.

12. In Item 2 at the bottom of p ge 3 of Enclosure 2 of the letter, TVA states:

"If the cables fail the high-voltage test, the NRC will be notified promptly."

COMMENTS ON TVA'S PROPOSED CABLE TEST PROGRAM Page 5 The NRC should witness all tests to assure that testing is done i

I in accord with TVA's commitment.

f

13. In Enclosure 2 of the letter, TVA provides cable acceptance criteria and what TVA will do if they have failures.

The NRC must reject this plan.

If failures occur, no options should be f

given.

All items must be tested prior to restart and all failed j

items must be replaced.

TVA's sampling is unacceptable and must be disallowed by the NRC.

)

The referenced sampling basis, hypergeometric likelihood density function method, as well as any number of other statistical sampling bases, is not applicable to the subject at hand.

Sampling theory, including the referenced one, assumes that a controlled activity is occurring such as manufacturing of like items on an assembly line.

Cable installation by different crews, in different configurations of conduit arrangements and sizes, with different mixes and sizes of cables, and with different plant environments does not allow classification in the same category as an assembly line type of operation.

For this reason, small samples cannot be used to make conclusions about large populations of cabling.

I

14. In Enclosure 3 of the letter, TVA references construction specification G-38, which has been deficient from the beginning.

Further, too much detail is spent on selection of conduits rather than in testing all of them.

Also, TVA states that cable selection criteria will be documented in a calculation.

When will it be done?

It would not have to be done if TVA would eliminate the sampling philosophy.

15. TVA has stated that IEEE 383-1974 was not the code of record with the implication that it did not have to f ollow it then or now.

This is ridiculous for a plant that had such a long construction time with delay after delay, operating for a while, now shutdown for serious problems, and not wanting to agree that j

IEEE 383-1974 is required to solve problems.

Who is kidding whom?

It would be irresponsible for the NRC to allow TVA to proceed on less than IEEE 383-1974.

\\

)

GENERAL COMMENT

S:

1. Reference 1 included a welcome review of the TVA cabling situation.

The meeting specified in Reference 2 set the right tone from the NRC viewpoint and served to put TVA on notice that TVA was not resolving serious concerns.

The NRC and Franklin Research Center are to be commended for both.

2. During a meeting with me on June 23, 1987, TVA personnel highlighted their cable testing program in an apparent effort to resolve questions I had raised.

Less than three weeks later, during the meeting specified in Reference 2, TVA told the NRC a very different story concerning their cable testing plans.

i

_j

COMMENTS ON TVA'S PROPOSED CABLE TEST PROGRAM Page 6 s

3. The NRC must witness all testing for some of the reasons given in Item 2 above.

4. The sampling mentality at TVA is unacceptable.

I believe that all cables in conduit must be tested and the failed items must be replaced prior to restart.

5. The NRC must insist on a periodic testing plan, with an acceptably short period of time between testing, for continuing the testing of all plant cables in conduits throughout the plant life.

This will assure that degraded cabling will be found and replaced.

6. The original test voltages used by TVA (in testing in which failures occurred) are not excessive and will not cause damage to 3

cabling that is in acceptable condition.

If cabling fails at J

that level, 240 volts / mil of insulation thickness (not minimum environmental qualification insulation thickness), then it should be replaced.

7. Water immersion testing must be included as part of the testing as described herein.

TVA's plan on this is unacceptable.

8. The pla ' cabling inventory should be checked for its qualified 11fe.

All cabling that is late in its qualified life should be replaced without testing.

9. In the meeting specified in Reference 2, and elsewhere, TVA tried to equate what they are doing with normal acceptance require testing and they referenced IEEE standards that only(600 volt) megger testing at 500 or 1000 volts for low voltage cabling.

They also tried to make a case for service condition versus rating.

The fact that all IEEE standards do not include adequate information for testing for known problems does not allow one to conclude that high potential testing is inappropriate for 600 volt insulation.

This is an area where TVA is misrepresenting the real reason for the need for high potential cable testing.

10. TVA's and its consultants' not being aware of any 240 volt per mil testing, as stated in the transcript of the July 13 meeting, raises questions as to the quality of the TVA consultants' advice.

This level of testing for 600 volt cabling has been used as a means of finding problems and replacing bad cabling.

The NRC should poll the nuclear utilities and possibly other industrial companies to see how they maintain confidence in their cable insulation levels through testing and at what levels and frequency of testing.

The NRC should also ask if any of them have any work in progress to update their current practices.

Certainly, the questionnaire should include the TVA type situation in which cable degradation is known or highly suspected and the utility or industrial would be trying to find the extent of degraded insulation.

i COMMENTS ON TVA'S PROPOSED CABLE TEST PROGRAM Page 7 11.

The TVA NSRS Report I-85-06-WBN, " Investigation of an Employee Concern Regarding Cable Routing, Installation, and Inspection at Watts Bar Nuclear Plant," by Mr. Mansour Guity, dated July 8, 1985, and the Technical Evaluation Report (Reference 1) by Franklin Research Center are in concert with my knowledge of the TVA cable situation.

Both of these provide substantial information to dispute TVA's claims of conservatism and good practices having been followed in cabling installation at TVA.

SUMMARY

The issue of cable testing is more far-reaching than the Sequoyah plant.

The NRC decision on this issue and the methodology to be used will be referenced as a major precedent.

Therefore, the relaxation or softening of requirements for immediate needs of economics and schedule of restart for Sequoyah should be overridden by the bigger issue of setting a precedent and the establishment of an NRC position.

The NRC staff has indicated that the NRC must be fair with TVA.

The NRC can be fair and tough as a regulator, but fairness and economics must follow safety which should have the highest priority.

l l

eB 5 055 3 -

seV 0 2 1

0 2 5 1 0 s

1 el L s e O 1 1 1 1 1 1 1 1 1 2 Tk.d a s C nt e k

e a t L ra g n

00 nA00505 05 05 pa 0 e sh0 c ol 0

0 n1 r i 0 5 1 0 1 5 1 1 1 1 2 2 1 1 223 o

c t

e

- V oP r

a C l

a f

05 5 t

3 5 55 00 0 5 0 sV 3 mk L e

1 0 6 1 4 0 6 1 4 8 4 Tk e D 1 1 2 2 3 1 2 2 2 3

,d a mC nl k

e a t i ra g n

055 055 0 0 pa 0 e nA 0 0 t

S 0

c o l

3 8 1 4 1 1 2 o1 eil J^ 3 3 2 2 3 3 4 6 1 c

ta o

1 2 V r J

o P l C f

tn a-t se 055 3 e l nl t B 55 00 0 5 0 e

g

- r 3 c u o 5 0 5 l

o3 uk l i v 4 8 2 a

t of 3 s e 0 6 1 4 0 G 1 4 8 4 1 usnt e 1

v 1 1 22 3 1 2 2 2 3 o

V 1 a l

P I L

o Vd eC l

V tsk nt L t

55 n

a-t a n e

00 0 5 0 0 e nA T

0 5 nl t

0 e l e, 0 cil 2 6 1 4 0 G 1 4 8 4 0 c u o e 5 0 0 5 s

o e

4 1 0 T

cg0 at o i v a

1 1 22 3 I 2 2 2 3 1 r s t

e n e

1

-4 a1 Pl C t

P I L

dna se D

s t

t s

n a E

e 055 3 el nl r

t B o3 -

3 c u o D

3 2 3 9 h

55 000 5 0 e

1 n l

2 k

o

f. 3 sc lo 3 5 1 8 0 5 1 8 9 1 1 es mL i

1 2 3 4 c

V

.1 n v n t 1

3 i Vd e C I

1 P I i

E h

t t L c

t t

s k n n eT t

t T

,a e nA n a i

b n e0 c ol 0 5 0 0 0 5 0 0 5 5 l

0 el nl S

3 8 1 8 2 r i 0 c u o e o

c g0 e t

o 4 f 1 8 0 5 1 8 9 1 1 1 2 3 4 r s i v a i a

1 1

1 e nt e

- a 1 P C

t T a a t 1

P I L

lu sn I

s.

m6 4 0 5 3 4 0 5 0 9 9 G 6 6 l

25 4

• e 2

69 m 1 1 4 6 0 1 4 z

i r

t

?

2 3 5 8 S

ol 0 1 1 1 2 1 1 1 1 2 a

n a u

3 3 el nl f

3 c u o e r

f s l

i v o

n 1 r s f I o

e n e

t t

P I L

0 0 5 5.

Cst 0 5 5 5 0 5 5 5 5 0 9 4 1 4 c

s t

u s nt eh im3 4 5 6 8 4 5 6 1 9 1 2 3 d

e n

n c e o

t r C

c e v d P e L

i 2

T3 n m4 2 3 1 9 2 8 5

9 25 0 1 5.

. g 16 0 3

e t

29 4 6 1 n1 o r

m1 5 0 4 1 t

t i

o n a o

t N

0 el n' 22 4 6 l d

A 1 1 22 2 1 1 2 2 3 it n

0 c u al s a l u e

1 r s !t ve I'= 0 o

e e n n 0 C

S P I e

s L

5 0 0 5 0 0 0 0 50 0 5 5 0 0 I 1 l

im4 6 8 9 1

$ 1 9 02 3 1 1 6 8 1

11 1 1 2 t

d f

e 0 0 0 0 0

0 d

0 0 0 0 c

r 0 0 0 0 0 0 i

e

/ 0 0 e

0 0 0 0 3

/ 0 0 l

1 1 1 1 a

oM 9 2 4 5 1 9 2 4 5 1 h

c e u zGC - - - - -

s 4 8 1 5 5 4 8 1 5 5 n

8 6 21 d

WM1 i

2 2 1

2 2 o

nS o

A 25 25 N

C 0

0 0 0 0 0

0 0 0 0 0

0 0 5 5 0

0 0

0 0

5 8 1 2 0

5

.o t e t e *s 6

-2 1 1 1 1 d l eug e

1 0 0 0 0 a es ak ks h o 0 0

0 0 0 0 a t 1

t c 0

a 0

25 8 5 R Coh P V 6

VP 2

N+"

i e

\\

g e

.,e 1 TE 9_ g2F g py V

%ar -

- - - - _ - - _ _ _ - _ - _ _ _ _