ML20055C729
| ML20055C729 | |
| Person / Time | |
|---|---|
| Site: | Seabrook  |
| Issue date: | 05/31/1990 |
| From: | Richardson J Office of Nuclear Reactor Regulation |
| To: | Leiderman S AFFILIATION NOT ASSIGNED |
| References | |
| NUDOCS 9006220235 | |
| Download: ML20055C729 (10) | |
Text
-
l l
l Stuart M. Leiderman ggy 3' g g 2 Sunsurf Avenue l
Hampton Beach, New Hampshire 03842
Dear Mr. Leiderman:
In response to the questions you posed to Mr. Victor Nerses in your letters
(
dated February 26 and March 25, 1990, regarding the Seabrook Station Unit 1 i
First Ten-Year Interval inservice Inspection Program Plan, I have provided l
answers in the enclosure. The enclosure contains your questions as stated l'
l followed by an answer. The answers provided relate to the Plan that was evaluated by the NRC staff with the results transmitted to Mr. Edward A.
Brnwn, President and Chief Executive Officer, Public Service Company of New 1
l Hampshire, by letter from the NRC dated February 15, 1990.
I hope that the answers provided clarify any misunderstanding you have concerning the inservice inspection program at Set 5 rook Station Unit 1.
Sincerely, kicir.31 Sicnod By:
Jc'.;;2... 4:ardsen James E. Richardson, Director Division of Engineering Technology i
Office of Nuclear Reactor Regulation
Enclosures:
As Stated DISTRIBUTION l
Central Files VNerses EMCB RF RWessman GJohnson NRC PDR.
1 RHermann CYCheng JERichardson LSpessard WTRussell JSniezek FJMiralgia TEMurley NRR Mailroom, Yellow ticket 90-67 CPaul 90-14
- SEE PREVIOUS CONCURRENCE i
EMCB:DET EMCB:DET EMCB:DET DET AE0Q P013-
- GJohnson:adl:tc *RHermann
- CYCheng
- JERichardsen RLSpessard RWessman 05/21/9 05/2 /90 0 /21/90 05/22/90 05/$/90 05/W90 l
f mb
/rIDT:NR
/
DD:F DEDRORg//
WRussell FMi lia q y
JSniezek l
l 05/d/90 05/A 90
/g790 05/;'90
~
/
0FFICIAL RECORD COPY Document Nane: LTR TO SLE!DERMAN/ ATTACHMENTS-f 00h S5 g
j 1
e i
ENCLOSURE' SEABROOK 1 QUESTIONS RESPONSE TO STUART M. LEIDERMAN LETTER OF February 26, 1990 l
i
- 1. What blueprints, plans, diagrars, catalogs, etc. are available to cross-reference the various welds described by code number in the package, with their actual location in Seabrook Station Unit 17 Would you provide me with that/those documents (s)?
ANS.:
The piping and instrument diagrams end iscmetric drawiros used to perform the cross-r'eference for the welds described by cede number in the Seabrook Station Unit 1 First Ten-Year Inservice Inspection Program are contained in enclosures to letters dated June 21, 1984 (SBN-672) and May 28, 1986 (SBN-1072) from Public Service of New Hampshire (PSNH) to the NRC.
These documents can be obtained frem the local public document room located in the building cited below:
l Exeter Public Library 46 Pleasant Street l
Exeter, N.H.
l L
- 2. Does each code, for example RCrRPV-1C3-121 in the Reactor Pressure Vessel, designate a) a single' weld or.a group of welds; b) an actual weld or a presumed weld in that/those location (s); or c) an area of actual or presumed welds; or is it a combination of these possibilities?
ANS.:
Each code, for-example RC-RPV-103-121, 4 >ignates a sinole weld in the locatian of its designation on a compcrent or pipe, t
- 3. Why are both surface and volunetric vt'd irspections required?
What is the~ relative importance and information value of each kind of inspection?
What are.
their principal distinct or overlapping objectives, with regard to plant and component integrity, safety, etc.?
ANS.:
Surface and volumetric weld inspections are nondestructive examination methods that indicate the presence of cracks or discontinuities on the I
surface and the presence of discontinuities l
throughout the volume of material, respectively.
L Ultrasonic weld examination is a volumetric method
~,.
o 2-used primarily for the detection of flaws below the surface of the material.
Dye penetrant and magnetic particle weld examinations are surface examination methods that can only detect' flaws when they originate at or penetrate the surface of the material.
Both surface and volumetric weld examinations are required by Section XI of the
-American Society of Mechanical Engineers (ASME)
Code for certain categories of welds because the areas most likely to develop flaws during service are either the inside or outside su' f aces rather than-within the wall of the material.
The inside' surfaces of most' pipes and components are inaccessible for performing surface examinations. -Therefore, ultrasonic examination which can be performed from the.outside surface provides the information necessary to determine the structural integrity of the pipe or component weld.
- 4. What is the expressed or implied reason why the American Society of Mechanical Engineers Code for the inspection of nuclear power plant components requires that 100f ef the plant's welds be inspected?
Would you supply me with' the documentation for this?
ANS.:
Section XI of the ASME Code dces not require 100%
of tbe plant's welds to be exemined.
Section XI is the Code used'for examination and test requirements after the construction phase of the facility is completed.
Section XI requires volumetric and/or.
surface examination of a percentage of welds in Class 1 and 2 systems and a hydrostatic test of all welds and base material of piping and components in Class 1, 2 and 3 systems each ten-year interval of the service life of the facility.
The welds of piping and components designed'to the rules of Section III of the1ASME Code are, required to be examined by one or more nondestructive l
examination methods.
These e.vaminations are required to ensure that the ccmponents and systems in which the wt1ds are located are structurally sound and free of unac.eptable flaws prior to plant operation.
As stated ir the Foreword of Section III, "The objective of the rule'is to afford reasonably certain protection of life and i
property and to provide a margin for deterioration in service so as to give a reasonably long safe.
period of usefulness".
i 1
3
- 5. From my reading of the package, PSNH has requested the NRC's permission to not inspect 100% of the welds in Seabrook Station's reactor pressure vessel, pressurizer, steam generator, Class I piping and Class 2 residual heat ren.cval piping.
In many cases PSNH has requests
- NRC's
" relief" to inspect less than 50% of the welds in these components and areas.
Would history of 100FR50-55a(g) (6)you provide me with the(i) that allows a nuclear power plant licensee (in this case, PSNil) to request relief from inspecting welds if the licensee determines that it is " impractical for his facility", as stated in this package?
Further, what is the percentage of nuclear power plant licensees in the U.S. that have exeretsed this provision?
What tests, criteria, deliberations.
hearings or other means are applied to these requests to insure that they "will not endanger life or property or the common defense and security, and are otherwise in the public interest, giving due consideration to the burden bron the licensee that would result if the requirements vere irpnsed", as stated in this provision, who applies it, what parties are normally involved, and what public participation ar'd appeal procedure is there?
ANS.: It appears that you have misinterpreted the requests in the package.
The requests apply to the areas or volumes of the welds to be examined, not to the number of welds.
The Code requires that, for instance, 100% of a weld in the reactor vessel be examined and the licensee determines that only 73% of that weld can be examined ~due to interference of the examination method by the close proximity of 1
an instrumentation nozzle.
This means that the i
licensee is examining 73% of the. required area j
and/or volume of the weld and requests relief from l
examining 27% of'the required area and/or volume of the weld due to the impracticality caused by the nozzle interference.
The renaining welds are still subjected to the requirements of the Code that they j
be examined 1004.
10 CFR EC.55a(g) was included in the regulatic.rs ir 1975 with the purpose of having the latest recuirerents and advarced exaritation and test retbces applied to nuclear power plants systers and cor.porents.
The regulations require that each nuclear power facility have an inservice inspr*tien progran and that this program be updated to tGe 4
w 4
latest edition and addtada of Section XI of the ASME Code each ten-year interval of facility operation, in some instances, these requirements could not be factored into the design of the facility for obvious reasons and therefore resulted in the impracticalities cited by the licensee.
In recognition ofEthis fact, the regulations allow these impracticalities to be reviewed and evaluated to determine if relief from the requirements can be granted without compromising plant safety and thereby' endangering public health and safety.
The licensee makes the determination that an examination or test requirement is' impractical to perform at its facility.
The licensee is required by 10 CFR 50.55a(g)(5)(iii) to notify the Commission that conformance with a certain Code requirement is impractical to perform at the facility and to i
submit +o the Commission information in support of the determination.
This information is evaluated by the Commission to determine if the requirement is impractical and if relief frem the requirement may be granted.
if the necessary findings are made, the Commission may grant relief from the requirement.
All licensees to cate have exercised this provision of the regulations.
Since granting relief from an impractical Code requirement is not one of the actions listed under Section 189 of the Atomic Energy Act of 1954, as
'i amended, 42 U.S.C. sec. 2239, a hearing is not granted by the Commission on this matter.
6.
I understand that this 10-year inservice inspection program is an important requirement to determine the structural and plant integrity changes that-tate-place over time, under various load conditions, whether the plant is operational or not.
Given +he provision of
" relief" from the inspection of welds, does this mean there is a possibility that some percentale of welds will Ei'ir Be Insjicii3} ju7eli iii'~3urTF~ Thii 10-year period on TEi 3?EEF3i BT---~~~~~~~~~~
Imj?icticITTtiT5E-~5r Sey3n37 Is this taken into Io the licen p3si!c3nii?uct account, contempleted or expected by '.he ASME Code that i,
i 1
O
, nonetheless requires 100% inspection?
If yes, where is this expressed or implied?
If no, how does ASME and the NRC identify and rank the inspection criticality (mv term) of welds in a nuclear power plant to insure that none of the most critical ones are exempted because the licensee claims that a certain percentage of them are (sic) impractical to inspect?
Where is that ranking for welds in the Seabrook Station?
ANS.:
Components and piping in nuclear power plants that are designed, fabricated, installed, examined, and tested in accordance with the requirements of Section !!! of the ASME Code are classified as ASliE Code Class 1, 2, or 3.
Each weld in the i
components and piping so classified is subjected to one or more of the examination methods discussed above during the construction phase of the facility.
After the constructio6 phase, the requirements of Section XI for preservice and inservice examinations and pressure tests are applicable.
The examinations required for the welds in each Code Class component and pipirg system depend on the particular Code Class.
The welds in Code 1
Class 1 cnmponents and piping systeme are subjected generally to strictc r requi,ements than those of Code Class 2.
The examination requirements for welds of Code Class 2 components and piping systems are subjected to stricter requirements than those of Code Class 3.
Section XI does not reouire that all welds in I
the f acility be examined each ten-year interval of.
facility operation.
A distributed sample of welds in Code Cir.ss 1 and 2 components and pipino systems is required to be examined periodically during the interval and all Code Class components and systems required to be hydrostatically pressure tested at or near the end of the ten-year interval.
If an examination rtveals the presence of a flaw, the sample size is required to be 4
expanded.
This expansion of the sample size could theoretically entail the examiration of 100% of the welds of components and piping systems if the sampling examinatinn identified significant problems.
l
6-
- 7. I en9arstand that most of the reasons PSNH cites welds a rt sectical to inspect has to do with design and I
cota z stion... a process that is coordinated by NRC, e
PSNH and the various contractors, viz., welds that are claimed to be obstructed or inaccessible in some way.
Please tell me who is accountable for cp'Ei'XTRE~toBE nstructina a nuclii?~j3wi?~~pTiET~TE~iucE~I wig TEIT"t ETTiiT5EiT~~5n~IEi 7 ViT~thTi 15p3?IinT ThipicIT3n~~
ciEnBI 5e~TUTTT1Ti3 New Hampshire seacoast, as well as in l
communities throughout the U.S.,
homeowner's commonly face the tre of building inspectors when wiring, pipes, etc. are unable to be inspected because they have been covered over with sheetrock or obstructed in other ways.
For the inspector to do his/her job pro 3erly, the walls are usually required to be rencved, witaout entert'ining
" requests for relief from inspection".
- Further, inspectors could not approve original-designs and blueprints that would prevent inspections being done later down the line.
What is unusual about the Seabrook Unit I design that p r e cl u 3ii~TUUY~ GIT 3 T niji CIT 3 n~3 u rT ni IETI TU!iiir TEiiivTei Tniji3IT5n7 Kii~ihy BIhir-~~~~~~^
TnipicTToni Br pi?T3r5iEci IETYi~ precluded by its design?
Why did the NRC permit such a design?
ANS.: All welds in ASME Code Class 1, ?, and 3 components and piping systems are requirec to be subjected to one or acre noncestructive exerinations and pressur, tests during th'e construction phase of the i
facility.
During the inservice phase of the facility, the Code requires that a sample of the population of welds-in the various systems and components be examined.
Review of the reasons why some of the welds selected for examination-during the ten-year interval at Seabrook Station tinit 1 cannot be examined 100%
as required by Section XILof the ASME Code reveals that in many cases weld geometry, not. plant design and construction as alluded to, prevents' full coverage of the weld volume required to be examined.
In rost cases, a high percentage of the required volume is being examined, thertty providing a high degree of cssurance that any flaws in the welds causec by inservice mechanisms will be detected.
1
, 8.
Finally, I would like to cross-reference welds for which PSNH has requested relief from inspecting with those cited in the June 4th, 1985 U.S. District Court, New Hampshire, Grand Jury indictment of James Vincent Padavano, weld inspector at Scabrook Station.
There were 11 counts to this indictment:
Count Field Weld Date of Number Number-3: port 15753-Re
~~I---
TR 15UU!TTU6 2
FW 4600-1407 3-2-83 3
FW 4601-1102 3-3-83 4
FW 4601-1103 3-3-83 5
FW 4601-1106 3-3-83 6
SW 1803-0202 2-17-83 7
SW 1803-0203 3-3-83 8
RC 801-0101 7-30-8?
9 CS 465-0101 10-23-82 10 NG 1656-0106 2-28-83 11 DG 4419-0307 1-17-83 Mr. Padavano entered a Plea Agreement of guilty to the first 4
two counts... concerning falsifying inspection reports.
My interest is not with Mr. Padavano per se, but in the thoroughness of NRC's coordination of information and safety matters during the entire lifetime of a nuclear power plant.
from design to construction to operation to decommissioning.
Therefore, I would like to know if the l
agency or its delegate has taken this particular matter into l
consideration in granting requests for relief from inspection, and further, what other welds in'the plant have come Ellili_i:I!!EIfa!_Silii_ii!!il-!!!EI!!ililli!_il:1?Il_II537-underSuestionin2scrutin 3T in-ITnB TETI iE5uTB riii3niSTF---
e ANS.:
The welds for which the Commistion has granted relief from some requirement of the Code are listed in Table 1 of Enclosure '. of the February 15, 1990 package to Mr. Edward A.
Brown, President and Chief Executive Officer, Public Service Company of New Hampshire.
None of the welos listed in Teble 1 4
is a weld that is included in the list for which Mr. Padavano was indicted.
We.now of no other welds in the plant that have erre under questioning scrutiny of any kind which we have granted relief i
l I
I i
i from examination requirements.
Any knowledge of irregularities in fabrication or examination of a l
weld would certainly be considered in the Commission's-findings made to grant relief from the Code requirements.
f Seabrook 1 Questions RESPONSES TO STUART LEIDERMAN LETTERS 0F MARCH 25, 1990 I
1.
Wtit is the total number of welds at Seabrook Station Unit 17 ANS.: The total number of-. welds at Seabrook Station Unit 1 l
is not known.
However, in reference to the Ten-Year Inservice inspection Program Plan, Revision 0, submitted to the NRC by letter dated April 14, 1987, the total number of welds required by Secton XI of the ASME Code to be included in the population of welds subject to examination is 3,717.
Other component examinations that do not involve welds, such as bolting and inner radii, increate this number to 4,437.
2.
Is this the total number of welds that would be subject to inspection if no requests for-relief has (sic) been asked for by PSNH?
If not, what is that number and what is the reason for the difference?
ANS.: No, this number does not-represent the total number of welds that would be examined if no requests for relief had been granted by the Commission.
The number of welds scheduled to be examined by the rules of Section XI in Class 1 and 2 systems is 907.
This number does not include other examinations that do not involve welds or the visual-examination requirement fer all welt!
when the Class 1, 2, and 3 sys tems and con.perents are subjected to pressure tests including the ten-year hydrostatic test.
l s
b
i i
9 3.
What is the total number of welds that PSNH is requesting relief from inspecting?
ANS.: The total number of welds for which PSNH is requesting relief from examining 100% is 105.
In all except four cases, significant percentages i
of the required examinations are being performed.
4 How do (sic) each of the answers in the above break down by a) welds which are considered safety related and b)
I those which are not considered safety related?
ANS.: All of the welds are considered safety related.
E.
How are there further broken down by systems within brit 1, using the same terminology used in the 10. Year Inservice Inspection document, viz., Reactor Pressure Vessel, Pressurizer, Steam Generator, Class 1 Piping, Class 2 Residual Heat Renoval Piping, etc., etc.?
ANS.: This information can be obtained from the submittal cited in the above answer to question #1.
t b
b
}
t i
.