ML19263E812
| ML19263E812 | |
| Person / Time | |
|---|---|
| Site: | 07000033 |
| Issue date: | 04/20/1979 |
| From: | Hopper C TEXAS INSTRUMENTS, INC. |
| To: | Partlow J NRC OFFICE OF NUCLEAR MATERIAL SAFETY & SAFEGUARDS (NMSS) |
| References | |
| NUDOCS 7906250310 | |
| Download: ML19263E812 (4) | |
Text
TEXAS INSTRUM ENTS,Og INCORPORATED
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MATERI ALS a ELECTRICAL PRODUCTS GROUP I~
P April 20, 1979 I
MAYO 81979 > Q,'
- u. s.
Mr. James G.
Partlow, Chief 4
Material Control Licensing Br.
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Division of Safeguards U.S.
Nuclear Regulatory Commission Washington, D.C.
20555
Reference:
SNM-23, Docket 70-33 _
-w
Subject:
Use of Shippers' Values at the HFIR Project of Texas Instruments Incorporated (TI)
Gentlemen:
As a result of a recent USNRC Region I Inspection and Enforcement Safeguards Inspection No. 79-06, TI has been instructed to inform you of TI's necessary r'etLod of determining LE's for inventory differences and shipments based upon the information available to TI.
To fulfill License No. SNM-23 requirements and USN!iC Regulations relative to the determination and use of limits of errors, the following statements and/or descriptions of calculations and use of LE's is provided.
TI is contractually obligated to utilize suppliers' weight percent uranium content of U 038, and weight percent 235U isotopic content of uranium for product loading calculation and eventual shipment of waste, scrap, or fuel elements. This means accountability records are also maintained using these values.
Attachment I provides a summary of determination and appli-cations of limits of errors for inventory difforences and shipments.
Attachment II provides a typical approach to the proposed management of L.E.
determinations.
Sincerely, 00v% ll1, k /jW Calvin M.
Hopper ppj} QfQ Manager Nuclear Safety CMH/ck , g' o ft % 12780 Attachments ATTLEBORO, M ASSACHUSETTS 02703 e TE LE PH M E: 617 222-2800 e C ABLE: TEMINS 7 90625 0 'J/D
ATTACHMENT I Determination and Applications of L.E.'s Inventory Differences When shippers' values are posted by TI, random and systematic weighing errors, as determined at TI are applied to each received bottle of U 038 introduced into process during a material balance period and subsequent weighing processes within the same material balance period. Since the input and output of the TI process are contractually required to be at suppliers' elemental and isotopic values, the elemental and isotopic values are covariant. Therefore, these elemental and isotopic errors do not contribute to the determination of limits of errors for the calculated inventory difference. The elemental LEID is determined from weighing LE and suppliers' weight percent uranium content as a constant. Shipments Random and systematic weighing errors, as determined at TI, are applied to item U 03 8 content L.E. Random and systematic elemental errors (first choice--suppliers' values, second choice--TI values) are combined with TI U 038 weighing errors to obtain item elemental content L.E. Suppliers' weight percent elemental values and TI loading calculation are used to determine item clemental content. Random and systematic isotopic errors (first choice--suppliers' values, second choice--TI values) are combined with TI loading calculation and TI weight percent elemental content errors to obtain item isotopic content L.E. Suppliers' weight percent isotopic values, weight percent elemental values, and TI loading calculations are used to determine item isotopic content. 2215 069 n7m
ATTACHMENT II 4 Typical Derivation of Formulae for L.E. Determinations 235U Isotopic: 235 I U U = Var U = (see previous determination) Var ( R Var I = + ^# N S( S 235 where U = Total net weight of U expressed in grams. I = Laboratory analysis of U isotope content as determined from the average of N replicate samples g results expressed as a weight fraction of uranium. N = Total number of replicate san ples results used for g determining the average I. Var (I) = Random variance of an isotopic analysis expressed as the weight fraction 235U in uranium, squared. Var (I) = Systematic variance of an isotopic analysis expressed g as the weight fraction 235U in uranium, squared. 235 Var U Var U Var I (235g)2 (U)2 (1)2 Var (I) R + N S Var U= (235U)2 VrU, _ S _J (U)2 (I)2 2215 070 12769
i ATTACIIMENT II Typical Derivation of Formulae for L.E. Determinations Uranium Elemental: U = SNM C Var SMM = N Var ( } + y R "I ^S ( ) ( Var C R = + Var M N g S where SNM = Total not weight of uraniun compound (e.g. U0) 38 expressed in grams. C = Laboratory analysis of chemistry as determined from the average of Ng replicate samples results expressed as a weight fraction. N = Total number of like itens (bottles of SNM or plates). 7 N = Total number of replicate samples results used for g determining the average C. VarR(W) = Random weighing variance for like items (bottles of SNM or plates) expressed in g2, Var"c(W) = Systematic weighing variance for like items (bottles of SNM or plates) expressed in g2, VarR(C) = Random variance of a chemical analysis expressed as the weight fraction uraniera in SNM, squared. Varg(C) = Systematic variance of a chemical analysis expressed as the weight fraction uranium in SNM, squared. Var U Var SNM Var C (U) 2 (SNM)2 (C)2 [- I VarR Var U = (U) 2 [1 VarR( +"I S j _ "S b 7 (SNM)2 (C)2 \\ u 2215 071 12769}}