ML19340A756
| ML19340A756 | |
| Person / Time | |
|---|---|
| Site: | Dresden  |
| Issue date: | 05/24/1977 |
| From: | Desiree Davis Office of Nuclear Reactor Regulation |
| To: | Bolger R COMMONWEALTH EDISON CO. |
| References | |
| NUDOCS 8009030781 | |
| Download: ML19340A756 (7) | |
Text
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7 MAY 2 41977 DIsa IBUTION:
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U DDavis Sil.ver JWetmore Comonwealth Edison Company LShao alt!!:
'fr. R. L. Bolger DEisenhut Assistant Vice President TABernathy P. O. Box 757 JBuchanan Chicago, Illinois 60690 ACRS (16)
Centlemeni Your letter of January 7,1977, proposed an inservice inspection program pursuant to 10 CFR 50.55a and requested relief from certain requirenents of 10 CFR 59.55a.
l?e are reviewing your submittal and have determined that the additional
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infernation requested in the enclosure is necessary to continue our review. To enable us to maintain our review schedule, please submit the requested infomation within 45 days.of the date of this letter.
Sincerely.
i Don.K, Davis. Acting Chief Operating Reactors Branch 52 Division of Operating Reactors I. closure:
rituest for Additional Infomation
= t/e' closure: See next pace l
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DRESDEN STATION UNIT l-r REVIEW 0F THE PROPOSED INSPECTION I
PROGRAM FOR COMPONENTS AND TESTING OF' PUMPS AND VALVES FOR THE 1977 TO 1980 PERIOD i
REQUEST FOR ADDITION,INFORMATION i
We have reviewed the proposed inservice inspection pregram titled "Dresden Special Report No. 45 for the 1977-1980 Period for Dresden Unit 1".
This program covers inservice inspection for Classes 1 and 2 components and inservice testing for Classi, 2 and 3 pumps and valves in order to comply with paragraph (g) of 10 CFR 50.55a.
" Inservice Inspection Requirements."
In reviewing the request for relief we find that additional information is needed in the following pro-
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gram areas:
i A.
Inservice Inspection Program for Class 1 Components (P.1) i 1.
Category E Add under Method of Examination; " Visual during pressure test (15500)"
i 2.
Category F The Code specifies that the Method of Exanination for this category is visual, surface and volumetric.
For items 1B and II in the program volumetric examination has been omitted.
Under Section IV (Pages 14 & 15) request for relief is addressed u.
for Category F.
It is not clear from this program whether relief appearing in pages 14 and 15 applies to those nozzles listed in the program (P. 1).
Clarification is necessary between the nozzles listed in the program-with those requesting relief under Section IV.
An alternative method for volumetric examination for nozzles l
listed in P. 1 should be specified.
5.
Inservice Inspection Program for Class 2 Components I. B (P. 5) 1.
The progran, is not clear with regard to definition of the com-ponents in systems as defined under the ASME Code Section XI paragraph'ISC 261.
Therefore the following information should i
be included as part of the program.
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i a.
Identify all systems that do not apoly but appear under.
ISC 261 a and c, including reactor pressure boundary components by IS 121(b).
Justify such systems that are i
not applicable other than those that don't exist.
Systems 1
that don't exist should be listed as such.
b.
Identify all systems or portions of systems that fall under ISC 261a.
l c.
Identify all systems or portions of systems that fall j_
under ISC 261 c.
I d.
Identify all systems or portions of systems that fall under ISC 261d.
Identify systems in this group where fluid chemistry is not verified.
Thus examination for those systems (where fluid chemistry is not verified) should i
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be examined in accordance with the requirements of ISC 261b.
All other systems falling under this group should be examined 1
in accordance with the reauirements of ISC 261c.
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4 e.
Compenents in systens or portions of systems identified in ISC 261 a and b should be examined in accordance with requirc-cents specified in Table ISC 261.
Where relief is sought 1
from the examination specified in Table ISC 26' technical justification and an alternative. method of a< amination should be part of the request for relief.
f.
Identify the boundary. condition for portions of systems to be 3
examinef and give technical justification for the boundary de-
- finition, l
2.
The control rod drive system falls under ISC 261a and therefore a
the examination category would be CF and not CG.
A request for relief should be submitted as part of the program if CG is selected.
i 3.
Category CG for CRD scram subsystem -
If the piping exceeds 4 inch nominal pipe size the examination shall be by volumetric means.
A visual inspection during hydro testingoas specified in the program is net acceptable.
And the CRD scram subsytem should fall under category CF (note comment 2).
If the piping is 4-inch nominal size or less visual during hydro 1
testing (IS 500) is acceptable.
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. a Catecaries CG and CF when specified should be ceneral in order to cover all applicable systems, i.e. all weld areas subject to examination as defined in Table ISC 251 and exist in systems as defined in ISC 261a and d (where fluid chemistry is not veri-fied) should be inspected except for those areas where request for relief has been granted.
C.
Inservice Testing Program For Pumps (P. 6) 1.
We have assumed that groups listed in the program constitutes a complete listing and meets the requirements of the scope (IUP 1300) in the subsection IWP " Inservice Testing Of Pumps In Nuclear Power Plants", i.e. all pumps of Code Classes 1, 2 and 3 which are provided with an emergency power source should be tested in accordance with subsection IUP of the ASME Code Section XI unless relief has been granted.
In the event that some additional pumps may in the future be identified to fall within the scope of this program (IWP 1300), we assume that such pumps will be inservice tested in accordance with the Code requirements.
2.
The regtmt for relief from the requirement for inservice test of pumps (IIIA P.10) has been reviewed.
As a result of this reviea additional justification should be furnished showing that other measured parameters will serve as alternative test-ing methods when monitoring the pump condition without reducing the level of plant safety (i.e. vibration measurements could serve as an alternative to bearing temperature).
D.
Inservice Testing Program For Valves (P. 6 thru 9) 1.
We have assumed that valves listed in the program constitutes a complete listing and meets the requirements of the scope (IUP 1200) in the subsection IWV " Inservice Inspection Testing of Valves In Nuclear Power Plants" i.e. all valves of Code Classes 1, 2 and 3 subject to the exclusion of IWV 1201 should be tested in accordance with subsection IWV of the ASME Code Se: tion XI unless specific relief has been granted.
In the event that va's ma; in the future be identified to fall within the scope of this program (IWV 1200), we assume that such valves when identified will be inservice tested in accordance with the code requirements.
2.
All Category "A" valves requesting relief on the leak rate test procedures -
The alternative leak rate test procedure by pressure decay rather than following the code requirement IWV 3420(4) is satisfactory provided that it can be shown that proposed alternative method is as accurate as the method recommended by the Code.
The function
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for Category A valves is not given in the procran.
3.
Sphe's Isolation The basis for requesting relief regarding applying pressure in the cpposite direction as will be applied while in service is found unacceptable.
The request for relief does not show that this deviation will maintain a comparable level of safety and does not give desion details showing the method prescribed bytheCodeIWV3a20(3)isimpractical.
In resolving this problem it is recommended that a detail drawing of a typical valve showing the internal design be submitted to f1RC for re y mt.
Also, submit detcils of the plant desicn that precludes the :es: of the valves in accordance with IWY 3420(3).
E.
Class I Cemconent Inspection Request for Relief (P.13) 1.
Category A " Pressure Retaining Welds In Reactor Vessel Beltline Regicn" The basis for relief is given as inaccessible because the regicn is surrounded in 6ft. of concrete.
Furnish additional infor ation consisting of:
a.
Give the annular space dimensicn between the pressure vessel and the concrete for possible examination by remote means.
b.
Prc;ose other alternative methods for inspecting these welds.
Steps should be taken to inspect these welds because the fluence on the material has approached si.5-1.8x1019 nyt E>lMev, c.
Consider performing the examination after the plant has been decontaminated.
If ycu have determined that these welds are impossible to examine, technical details must be furnished justifying relief.
You should also furnish (if applicable) a descriptien of future plans regarding flDE for these welds, because we can-not justify not inspecting these welds throughout the plant life.
2.
Categories B, D, F &.I-2 (P. 13-15)
Your request for relief should furnish the follcwing information:
A.
Shcw details including sketches, dimensions and any other technical details justifying accessibility as a basis for relief.
. B.
In regard to high radiation fields you should consider performing the inspection after decontamination when radiation fields are low.
If a relief request is based on high radiation fields, the following information should be provided.
1.
The expected radiation field after decontamination in areas where in:pection is to occur.
2.
Reasons why activity cannot be lowered to permit in-spection.
3.
What actions will be taken enabling inspection in some future date.
Give expected date.
4.
Furnish the level of exposure to personnel that can be expected if the inspection is performed by remote means.
Has remote means been considered?
C.
As part of the request for relief alternative metnods for inspection should be addressed.
It should be noted that existing standoff insulation collars surrounding dissimilar metal welds is not considered adequate ground for granting relief, unless it can be shown that such insulating collars cannot be relocated away from the welds zones.
The difficulty of removing and replacing brick insulation is not considered a just cause for granting relief because a design change can be initiated after decontamination permittirg future accessi-bility for the weld area inspection.
3.
Category H (P. 15) a.
First Paragraph Please furnish details (technical) of inaccessability in the bottom head area and irregular support.
What portions of the supports are accessible (i.e., not encased in ccncrete)?
b.
Second Paragraph Show details of the weld design and the location that would-explain why meaningful UT examination cannot be achieved.
Have you considered RT as an alternative or other means?
... c.
Third Paragraph IS 121a exclusion criteria excludes a component from inspection if the ccaponent is not required during normal operation, to bring the reactor to shutdown condition and orderly cocidown.
This paragraph does state the 26 support hangers do not support the drum during steam operation but neither the shutdown nor the cooldown phases are addressed.
A further explanation of the function of these 26 supports should be given.
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