ML20199J997
| ML20199J997 | |
| Person / Time | |
|---|---|
| Site: | Portsmouth Gaseous Diffusion Plant, Paducah Gaseous Diffusion Plant |
| Issue date: | 01/30/1998 |
| From: | Toelle S UNITED STATES ENRICHMENT CORP. (USEC) |
| To: | NRC OFFICE OF ADMINISTRATION (ADM) |
| References | |
| RTR-REGGD-XX.XXX, TASK-*****, TASK-OR GDP-98-0014, GDP-98-14, NUDOCS 9802060078 | |
| Download: ML20199J997 (9) | |
Text
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4 USEC A Clobal Energy Company g
n January 30,1998 b
Y Rules and Directives Branch, DAS SERIAL: GDP 98-0014 Office of Administration U. S. Nuclear Regulatory Commission Washington, DC 20555-0001
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Paducah Gaseous Diffusion Plant (PGDP)
Portsmouth Gaseous Diffusion Plant (PORTE)
Docket Nos. 70-7001 and 70-7002 Comments on Draft Regulatory Guide DG-1070 This letter provides the United States Enrichment Corporation (USEC) comments on Draft Regulatory Guide 901070, " Sampling Plans Used for Dedicat'a;' Simpie Metallic Commercial Grade items for Use in Nuclear Power Plants, USEC's comments are provided in Enclorure 1.
If you have ay questions regarding this submittal, please contact Mark Lombard at (301) 564-3248. There are no new commitments contained in this submittal.
Sincerely,
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I S. 4, i
Steven A.Talle Nuclear Regulatory Assurance and Policy Manager P
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NRC Region 111 NRC Resid:at Inspector - PGDP NRC Resident Inspector - PORTS NRC Special Projects Branch, NMSS lfD Iffffj fff
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{DR 6903 Rockledge Drive, Bethesda, MD 20817-18 t h Telepnone 301-564 3200 Fax 301-564-3201 http://www.usec.com Offices in Livermore, CA Paducah, ICJ Portsmouth,011 Washington, DC 1
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GDP 98-0014 Page 1 of 8 Backeround Recently, the Nuclear Regulatory Commission (NRC) has indicated a concem with sampling in the commercial grade item dedication process. The NRC has issued Dran Regulatory Guide (DG-1070), " Sampling Plans for Dedicating Simple, Metallic Commercial Grade items at Nuclear Power Plants" to provide additional guidance in this area.
Since the United States Enrichment Corporation (USEC) utilizes some of the industry gu! dance that has been developed by nuclear utilities, USEC is very interested in the promulgation of any NRC regulations that could impact that industry guidance. USEC also participates in several nuclear industry organizations. One of these organizations, namely the Nuclear Energy :..
..:te (NEI), has coordinated a reviev of DG-1070 and has compiled comments from several sources This enclosure, developed from the industry comments compiled by NEI, seeks to explain why he USEC and representatives from various nu:: lear utilities believe additional NRC guidance is not iceded to ensure that quality spare parts and equipment continues to be installed in operating nuclear plants.
Scope of Draft Reculatorv Guide The Dran Regulatory Guide states that it applies only to simple metallic items. It is assumed that this DraR Regulatory Guide would be the regulatory position for all dedicated items and not just simple metallic items, it is also assumed that if an inspector is reviewing a supplier or licensee dedication plan for any item, the sampling size would be reviewed, in the absence of any other alternative, the inspector would likely default to the Regulatory Guide for acceptable samping practices (this could also be the case for certificate holders li' e USEC).
The DraR Regulatory Guide also states that it applies only to items intended for high safety significant plant applications, or where the piant application is not known. This would require that licensees would almost always be defaulting to the NRC recommended plan (95/5) for the following reasons:
1.
Most licensees have not performed a safety / risk analysis down to the component level and do not intend to because of the required investment. The Dran Regulatory Guide implies that unless the safety significance has been determined, it must be assumed to be high and the 95/5 confidence levei.aust be used.
2.
Most licensees procure and stock items for general plant use. These items are dedicated based on the most restrictive or scvere plant application. The Draft Regulatory Guide implies that either separate stock numbers must be generated for separate applications, or the NRC recommended sampling sizes must be used.
3.
Suppliers are typically not aware of the safety significance of the plant application they are supplying the dedicated item for.
GDP 98-0014 Page 2 of 8 Based on the fact that the Draft Regulatory Guide may notjust be applied to simple metallic parts, and assuming that it applies to those items which are of high safety significance and/or have not had their safety significance determined, this Draft Regulatory Guide would apply to almost all licensee and supplier dedications.
Performance Illstory of Dedicated Commercial Grade items Since licensees and 10 CFR 50, Appendix B suppliers first implemenu enhanced dedication programs in the mid to late 1980s, they have utilized sampling plans when accepting commercial grade items. Based on the following considerations, performance of these items has oeen adequate to ensure safe plant operation:
Safety and i.on-safety related equipment procured and installed in operating units continues to demonstrate a high degree of reliability There is a lack of insei,i~ failures of safety related parts and components related to dedication Plant ieliability continues to increase even as the number of Appendix B suppliers is shrinking and the amount of dedication is increasing.
There is a lack of adverse trends in the quality of material procured as shown by utility QC tests and inspection results.
i No appreciable failure rates for the amplified testing (overchecks).ifastener performed during the late 1980s and early 199s exists.
As the NRC states in the int oduction of their Technical Report on sampling issued last February,"Through the years, NPP experience has shown that, in general, most plant equipment can be counted o 1 to operate reliably and safely. This observation is also true concerning the parts used i
to repair or replace that equipment."
To support the licensee perception that dedicated item., are performing well in mice, a survey was issued to gather data. Nuclear utilities were asked to provide the number ofitems that they have dedicated since January 1994 and the number of failures that were identified related to the dedication process. The following table summarizes the data sub-itted:
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GDF 98-0014 =
_ Page 3 of 8 Utility
- of Units
' Number ofiter.. Dedicated Namt cr ofitems Tiaat Have Failed
-A-
.3 3,645 stock numbers.
Nonc 1,200 non-stock numbers -
B 4
3,118 P.O. line items None C
7 2,500 commercial grade parts issued 27 (none were simple metallic parts)
D-2 310,000 individual parts -
None E
4
-133,924 None F
12-48,000 line items None
'O-1 4,000 line items None II 4
3,107 P.O. line items None i
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-218 line items None
-J 2
1,000 line items None K
I 1,207 line items None L
8 1,700 individual componentdparts None Because of the nature of the data supplied by the utilities, it is difficult to extrapolate an approximate number for the entire industry. One line item could equal 10,20 or 50 actual items.
' However, the results do indicate high performance and a lack of appreciable failures of dedicated itema.
. Renulatorv Basis for Samnline Durine the Dedication Process To ensure that the current sampling programs are in accordance with regulatory requirements, various regulatory documents were investigated to extract any guidance related to sampling:
1.
10 CFR 50, Appendix B, Criterion VII states:
Measures shall be established to assuie that purchased material, equipment, and services, whether purchased directly or th;ough cont actors and subcontractors, conform to the procurement documents. These measures shall include provbions, as appropriate, for source evaluation und selection, obje9ive evidence of quality furn%ed by the contractor or subcontractor, inspection at the contractor source. and ssaminatiorulf.prou.ats umn deliverv...The effectiveness of the control of quality by contractors m.!
$ nontractors shall be reassessed by the applicant or designee at intsmls consistern with the imoortance. comnlexity. and cuantity of the roducts or services.
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UDP 98-0014 Page 4 of 8 2.
The introduction of 10 CFR 50, Appendix B states:
... quality assurance comprises all those planned and systematic actions necessary to provide adequate confidence that a structure, system, or component will perform satisfactorily in service."
3.
ANSI N45.2.2 1977, Paragraph 11 states:
Examinations, measurements, or tests ofite.ns processed shall be performed for each work operation where necessary to assure quality. Where a sample is used to verify t.cceptability of a group of items, the sampling procedure shall be based on recognized standard practices and shall provide adequatejustification for the sample size and selection process.
3.
ANSI N45.2.13 1976, Section 7.3.2 (endorsef v Reg. Guioe 1.123) states:
Sampling may be used during receipt inspection when conducted in a accordance l
with established procedures or recognized standards.
l 4.
ANSI N45.2.2 - 1972, Section 5.2.2 (endorsed by Reg. Guide 1.38) states:
Statistical smpling methods may be used for groups of similar ite ns.
5.
10 CFR 21 defines commercial grade dedication to be:
... dedication is an acceptan:e process undertaken to provide reasonable assurance that a commercial grade iten-to be used as a basic component will perform its intended safety function and, in this respect, is deemed equivalent to an item designed and manufactured under a 10 CFR 50, Appendix B, quality assurance program.
Therefore, the procurement and dedication process isjust one of the elements of a plant's overall quality assurance program.
Cost of Reculatorv Guide Implementation The cost to implement the guidance provided on the Draf, Regulatory Guide would be significant to the industry. The guide not only provides a tighter sampling size than most licensees and suppliers use on larger lots, but it provides recommended critical characteristics and acceptance criteria for simple metallic items. Increased costs would be caused by the following:
The man-hours required to complete additional testing will require adding personnel to staff.
The procurement of additional test equipment to accommodate increased testing.
GDP 98-0014 Page 5 of 8 Increased numbei of stock numbers nnd total stock to accommodate different levels of safety significance.
The cost to revise current procurement engineering and dedication procedures to address revised sampling practices.
The cost to revise all current dedication plans.
The increased cost ofitems that were dedicated by approved 10 CFR 50, Appendix B suppliers who significantly increase sampling because they must assume items are intended for safety-significant applicatichs.
Increased engineering time to evaluate homogeneity oflot. There will also be increased costs to obtain the level oflot homogeneity the Regulatory Guide recommends before sampling.
Many of the tests the NRC considers nondestructive,'.vould actually be destructive for smal' simple metallic items. Therefore, a significant number of additional products would need l
- to be procured.
Increased off-site testing becattse many utilities and suppliers do not currently have all of the test equipment required to complete testing specified in the Draft Regulatory Guide.
The time to complete dedication will be increased.which may have an affect on parts availability to support plant operation.
The cost of obtaining additional paperwork from suppliers (such as, CMTRs, Certificates of Conformance, etc.)
The followag hypothetical example war developed to illustrate the additional costs which would be incurred using the guidance provided in the Draft Regulatory Guide, item to procured: 1/2 x 20 bolts, ASTM A307 Grade A, carbon st:el Number items to be procured: 100
. Cost per item: $.08 Scenario A: Current Utility Sampline Practicss According to the Jdnt Utility Task Group (JUTG) Technical Evaluation CGIFA01, " Dolts, 1/4 Inch and Above", the fol'iowing critical characteristics would be verified to provide reasonable assurance the bolts would perform their safety function:
Material compesition Material strength (see Note 1)
Coating or plating material
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GDP 98-0014 Page 6 of 8 J
l Cor. figuration (hex head, l'eavy hex, etc.)
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Pitch diameter or size l
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Threads per inch or pitch Overall length
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Ilead height Width across flats or head diameter Thread length Note: Appropriate test methods include tensile, load or hardness tests depending upon specific size, geometry and material type. Tests should be conducted in accordance with appropriate industry standard test techniques. Hardness may be used in lieu of tensile or load testing for appropriate materials. ASTM A370 establiohes a correlation between hardness values and approximate tensile strengths for carbon and alloy steels. Ilowever, surface hardness variations may be present due to heat treatment, machining or other working of the material. The applicability of the ASTM A370 correlation of hardness to desired mechanical properties should be reviewed as appropiiate l
Based on an engineering revit v of factors including dedication history, lot formation type, cc.nplexity of the item, inservice performance history, engineering would develop a sample size.
For this example, the uormal sample size out of EPRI Report NP-7218 is selected which results in a sample size of 18. It is assumed that using available test equipment, all dedication testing (including the hardness to verify material strength) can be performed without destroying the bolt.
For this example, it is assumed the fully burdened rate of receipt inspection / testing personnel is
$50.00 per hour, it would take approximately three hours for the items to be teud. Therefore the total cost for this procurement would be $158.00 (testing cost plus the cost of the material).
Scenario H: Draft Renulatory Guide Practices Based on a review of the Drall Regulatory Guide, the following additional characteristics / testing would be required:
Full chemistry composition analysis within tolerances specified in Draft Regulatory Guide
($250)
Full physical testing as specified in Draft Regulatory Guide including destructive testing ($250)
Procurement of CMTR or other paperwork to develop lot homogeneity requirements ($250) l-W
GDP 98-0014 Page 7 of 8 f
Review of papenvork against requirements in Draft Regulatory Guide (one additional man hour)
Preparation ofitem and papenvork to ship for oft-site testing and review of results upon rec.ipt back at the warehouse (3 additional man hours)
The additional cost to the procurement utilizing the Drail Regulatory Guide is $950.16 which includes the cost of two bolts to destroy. The total cost increases from $150.00 to 1,150.16 which is a factor of 7.6.
Past and Proposed Actions to Resolve Perceived Sampline Issue s
in 1995. representatives from the Nuclear Utility Procurement Issues Committee (NUPIC)
{
Steering Committ:e met with the NRC to discuss procurement. It was suggested that utility auditors need to better document the review of sampling activities. As a result, the NUPIC checklist was revised and additional guidance has been provided to auditors.
The NUPIC checklist has been revised to provide additional guidance on ensuring that manufacturers have a teetnically justifiable sampling plan.
The nuclear industry will sponsor several workshops to inform manufacturers and licensee pror urement and audit personnel on what nuclear utilities consider to be a technically justifiable sampling plan. Information developed for the workshop will be used to enhance the EPRI Nuclear Procurement Training Course Module on Sampiing in the Dedication Process.
The Electric Power Research Institute has made EPRI Report NP-7218, " Utilization of Sampling Plans for CGI Acceptance", available to all licensees and suppliers who have requested a copy. The report is presented as one industry-recognized standard practice to consider. Licensee members have also directed EPRI to develop a revision to NP-7218 to address the following issues:
Sampling sizes ior destructive testing Consideratitn of safety function and safety significance when selecting a sample size a
Lot homogeneity considerations The revision will be initiated in January 1998 and should be completed by June of the same year.
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GDP 93-0014 Page 8 of 8 -
Conclusion
- Based on the excellent performance history of dedicated commercial grade items, USEC believes that the current sampling programs utilized by licensees and 10 CFR 50,' Appendix _B
- manufacturers / suppliers are adequate to ensure safe operation of nuclear plants. The licensees
- believe that the sampling plans utilized are in accordance with current regulatory requirements and
' industry standards, and that no additional guidance from the NRC is required.
-USEC also believes that _impleinentation of the recommendations provided in Draft Regulatory Guide DG-1070 would significantly ixxeose the cost of procurement without improving.
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the quality installed items.
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