ML20087P199
| ML20087P199 | |
| Person / Time | |
|---|---|
| Site: | Brunswick  |
| Issue date: | 03/28/1984 |
| From: | Charnley J, Sund H, Wenner T NUTECH ENGINEERS, INC. |
| To: | |
| Shared Package | |
| ML20087P197 | List: |
| References | |
| CPL-17-103, CPL-17-103-R, CPL-17-103-R00, NUDOCS 8404060151 | |
| Download: ML20087P199 (31) | |
Text
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NUTECH CONTROLLED COPY CPL-17-103 Revision 0 l f. March 1984 CPL 017.0103 STATISTICAL EVALUATION l
OF
, POSTULATED FLAWS I AT BRUNSWICK STEAM ELECTRIC PLANT UNIT 1
... Prepared for:
Carolina Power and Light Company Prepared by:
NUTECH, Engineers, Inc.
- San Jose, California
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[ Prepared by: -
Issued by:
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E. T arnley, P.E.
J. H. J. Sund gy t Project Engineer Project Manager ,-
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,; Approved by: .
- r. M Date MAQ.CH 16,1969 T. N Wenner, P.E.
Engineering Manager 8404060151 840402
-"PDR ADOCK 05000325 eoa nutgch
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REVISION CONTROL SHEET TITLE: Statistical Evaluation of DOCUMENT FILE NUMBER: CPL-17-103 Postulated Flaws at Brunswick Steam Electric Plant Unit 1 J. E. Charnlev/ Staff Encineer b1N *M s NAME / TITLE INITIALS H. L. Gustin / Senior Engineer NAME / TITLE INITIALS D. C. Talbott/ Associate Engineer NAME/ TITLE
[f INldALS
! I' T. Lem/ Associate Engineer NAME / TITLE INITIALS NAME / TITLE INITIALS
'}' AFFECTED DOC PREPARED ACCURACY CRITERIA AEMARKS PAGE(S) REV BY / DATE CHECK BY / DATE CHECK BY / DATE 1
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CPL-17-103 CEP 3 3.1.1 REV 1 Revision 0 ii - - - - -- --
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N TABLE OF CONTENTS Page
1.0 INTRODUCTION
1
2.0 BACKGROUND
2 3.0 ASSUMPTIONS 3 3.1 Crack Orientation 3
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3.2 Initial Crack Depth 3 3.3 Crack Length 4
4.0 CONCLUSION
S 6 5.0 ANALYSIS 8 5.1 Initial Crack Depth 8 5.2 Weld Residual Stress 9 5.3 Applied Stress 10 5.4 Crack Growth Law 11 5.5 Crack Growth Calculations 13
6.0 REFERENCES
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LIST OF TABLES Table- Title Page 3'.1 Comparison of Releva'nt IGSCC Parameters 5
?
of Brunswick Units 1 and 2 5.1 Circumferential Crack Depths 17
, 5.2 28" Pipe Crack Growth Results 18 5.3 12" Pipe Crack Growth Results 20 t
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LIST OF FIGURES Figure Title Page 5.1 Residual Axial Stress in Large Diameter 23
- C- Pipe (> 12" ()
5.2 Residual Axial Stress in Small Diameter 24 Pipe (< 12" 6) .
5.3 Crack Growth Laws 25 i
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m-1.0 ' INTRODUCTION The purpose of this report is to document the results of a statistical evaluation of postulated intergranular stress corrosion crack (IGSCC) growth in the Brunswick Unit,1 recirculation piping system. The evaluation consisted of reviewing the cracks detected in the
,; Brunswick Unit 2 recirculation piping system following full UT-inspection during late 1983, performing crack
-ut growth calculations using that data, and then applying those results to the Brunswick Unit I recirculation
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piping system. This approach is creditable in that the two units exhibit similar characteristics pertaining to material composition, geometric configuration, sys' tem loads, and operational conditions.
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The result's of the evaluation show that the probability p, of circumferential crdcks growing to an unacceptable size (Reference 1) before the scheduled refueling outage
- N for Brunswick Unit 1 in November 1984 is~very low.
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2.0 BACKGROUND
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Brunswick Unit I has only had a limited number of welds
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examined per IE Bulletin 83-02 and is not scheduled for another such examination until the next refueling outage scheduled for November 1984.
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Inspections per IE Bulletin 83-02 were performed at Brunswick Unit 2 during an outage in November 1983.
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During that outage, 131 welds were examined in the ~
' recirculation, residual heat removal (RHR) and reactor
,b, water cleanup (RWCU) systems. Ultrasonic (UT)
, inspection indications were found in 19 of the 131 welds
. that were judged to be due to IGSCC. Eight of those
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welds were repaired with weld overlays while the
..., remaining eleven were shown to be acceptable without
- J. repair for at least one fuel cycle (Reference 2).
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3.0 ASSUMPTIONS _
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The following assumptions were used in the statistical evaluation of IGSCC data from Brunswick Unit 2 for application to a Brunswick Unit 1 prediction of unacceptable IGSCC by November 1984.
- 1) 3.1 Crack' Orientation Only circumferential cracks were considered. Axial IGSCC is limited in length to the. width of the weld heat
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affected zones. Axial IGSCC will not lead to a pipe failure either by plastic collapse or tearing I
instability. Thus, axial cracks are not structurally limiting.
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. 3.2 Initial Crack Depth 5C Table 3.1 presents a compa,rison between Brunswick Units 1 and 2 of the relevant factors which contribute to IGSCC. Inspection of Table 3.1 shows that Units 1 and 2
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have approximately equal propensity for IGSCC after an ,
'd equal number of operating hours. As of February 28,
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1984, Unit 2 had accumulated 8,300 more hot critical hours than Unit 1. Assuming uninterrupted operation, CPL-17-103 3 Revision 0 nutsch J
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Unit 1 should have 'an equivalent amount of IGSCC in
. November 1984 as Unit 2 had in December 1983, when it was examined. During the Unit 1 examination that was e
!- performed in November 1983, two welds had UT indications that were already sized at depths comparable to those observed in Unit 2 in December 1983. Therefore, to be conservative, it was assumed in this evaluation that Units 1 and 2, as of December 1983, had similar IGSCC
, depths.
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3.3 Crack Length
) All cracks in large diameter pipes were conservatively assumed to be 360*.
This assumption allows the use of i -
the nonlinear stress distributions which are analytic-ally predicted for large pipe.
All cracks in small It diameter pipe wdre assymed to have a crack length equal
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to ten times the maximum crack depth. This assumption
'd is justified because the appropriate residual stress l distributions are linear. ,Therefore finite length s[.
cracks may be analyzed. -
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Table 3.1 COMPARISON OF RELEVANT IGSCC PARAMETERS OF BRUNSWlCF. UNITS 1 AND 2 e
Brunswick Brunswick Parameter _ Unit 1 Unit 2
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Material 304 stainless steel 3 4 stainless steel Designer General Electric General Electric
$ Fabricators Associated' Piping Associated Piping M. W. Kellog M. W. Kellog Installers General Electric General Electric
( Brown and Root Brown and Root Carbon. Content 0.04% - 0.075% .04% - 0.075%
Water Chemistry No significant No significant difference between difference between the Units the Units Hot Critical Hours 37,760 46,065 e
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4.0 CONCLUSION
S The following conclusions can be made from the evaluation results:
a) There are no flaws in piping with diameters greater than 12 inches which are predicted to reach an unacceptable depth (Reference 1) by November
, 1984. With 99. percent confidence, the deepest flaw in large diameter pipe at that time will be less than 0.60 inch with an allowable depth of 0.79 inch (based upon a wall thickness of 1.26").
b)- For 12" and under welds, with the entire range of values of the crack growth law, weld residual stress, applied stress and initial crack size, the I
statistical results indicate that two welds could
, have unacceptable flaws by November 1984. However, the following additional considerations offset Q *
, those results:
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- 1. Although it was assumed that Brunswick Units 1 and 2 are identical from an IGSCC perspective,,
I" Unit 1 has operated 8300 fewer hours.
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. 2. Those cases that resulted in unacceptable crack sizes were based on very conservative analyses, i.e. , high crack growth rates and other conservative assumptions.
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- 3. A total of 24 12" and smaller welds, including those welds with the highest applied stress es (the 12" pipe-to-safe end welds), were inspected by UT in January 1983, and no circumferential cracks were discovered. The
- unit has operated only 7 months since then.
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Therefore, for 12" and smaller piping, tihe
.._. probability that unit operation until November 1984
,(7 will result in unacceptable cracks is very low.
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5.0 ANALYSIS
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. IGSCC growth is a function of four major variables; initial crack size, weld residual stress, applied stress and crack growth law. The calculation of the expected size of IGSCC in Brunswick Unit 1 by November 1984 is based on determining tha expected range of each of these variables and then performing many crack growth analyses
, to obtain a distribution of final crack depths. Because of the significantly different weld residual stress patterns in pipe diameters equal to or less than 12" as compared to diameters greater than 12", two separate final crack size distributions were calculated.
- [ 5.1 Initial Crack Depth Table 5.1 contains the , maximum reported depth of the eighteen circumferential indications from the Brunswick Unit 2 inspections (Reference 2) and the two circum-ferential indications from the Brunswick Unit 1 inspection (Reference 3).
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From Table 5.1, it can be seen that of the welds examined in pipes with a diameter less than or equal to 12",.8 had circumferential cracks with a mean (R) depth of 11.2% of wall and a standard deviation (s) of 3.45%'
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4 of wall. Similarly, for pipe with a diameter greater than 12", 12 had circumferential, cracks with a mean depth of 19% of wall and a standard deviation of 4.48%
of wall. For each size of pipe, three initial crack sizes were chosen to represent the expected crack distribution in Unit 1 as of December 1983. Those sizes were Y-2S, Y, and i+2S. Thus, for 12* pipe with a wall thickness of 0.568", the initial sizes were 0.025",
.r 0.064", and 0.10". Similarly, for 28" pipe with a wall thickness of 1.26", the initial sizes were 0.13", 0.24",
and 0.35". .
5.2 Weld Residual Stress The' variation in weld residual stress is difficult to
, quantify. The NUTECH standard weld residual distribu-Y' tions for both 12" and 28" pipe (Reference 9) were used as the conservative (high growth rate) distributions.
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For 28" pipe, the best estimate and the optimistic 3
distributions were obtained from Reference 4. The best j -
- estimate distribution was identified 'as the average case in Reference 4 and the optimistic case was identified as ii 'li * -
the Harris case in Reference 4. All three distributions l7 are shown on Figure 5.1.
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CPL-17-103 9 Revision 0 ritat_ ESC:I_
For 12" pipe, it was conservatively assumed that all distributions are linear. The best estimate and optimistic distributions were obtained from the Reference 9 conservativo distribution by reducing the maximum stress by 5 ksi and 15 ksi, respectively. All three distributions are shown in Figure 5.2.
5.3 Applied stress
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The applied stresses that are important for crack growth
,in a given weld are those that exist during normal operat. ion, such as dead weight, pressure, steady state thermal expansion and bending stress due to shrinkage of weld overlays at other locations. Dead weight and pressure stresses were obtained from Reference 5.
Steady state thermal and weld overlay shrinkage stresses were obtained from Reference 3.
For pipe larger than 12", maximum values of stress due to pressure plus dead weight, steady state thermal, and weld shrinkage are 8500 ps'i, 6200 psi and 300 psi, I
. respectively.
Even though these stresses do not occur at the same location, it was conservatively assumed that the highest stress was equal to their sum (15,000 *
, psi). The minimum stress was obtained by adding the pressure stress of 5800 psi and the minimum thermal n
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- expansion stress of 600 for a total stress of 6400 psi. The mean stress was judged to be 8300 psi.
For 12" and smaller pipe, the maximum stress due to pressure plus dead weight, steady state thermal and weld shrinkage are 12,200 psi, 11,300 psi and 3400 psi, respectively. Again these stress values do not occur at the same locations. Since the maximum t.hermal stress was abnormally high, it would have been overly con-servative to add all the maximum stress values.
The
. location with the highest total stress is in the N2C recirculation inlet safe end to pipe weld with a pressure plus dead weight stress of 11,100 psi, a steady
, state thermal stress of 7,300 psi and a small weld shr'inkage stress assumed to be 400 psi. Thus, the worst case total stress is 18,800 psi. The minimum stress'was obtained by addi,ng the minimum pressure stress of 7000 il psi to the minimum stea'dy state thermal stress of 500 for a total stress of 7500 psi. The mean stress was se judged to be 11,000 psi.
5.4 Crack Growth Law The typical steady state conditions duri,ng IGSCC growth n are welding sensitization, 0.2 ppm oxygen water
. chemistry and constant load. An extensive search of CPL-17-103 11 Revision 0 -
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existing crack growth information was performed.
However, only one set of data was found (Reference 6) which meets the above conditions. These data are shown -
in Figure 5.3. U'pper bound, best e. stimate and lower bound crack growth equations voro determined as follows:
Upper Bound ga -9 dt
= 8.23 x 10 K*
Best Estimate f
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= 2.50 x 10 ' K
- Lower Bound f =
9.091 x 10] OK.
37 Where':
da = Dif ferential Crack Depth (inches) dt =
Differential Time (hours)
K =
Stress Intensity Factor (ksi,jinches)
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CPL-17-103 12 Revision 0 r1titt_at.:.l1
5.5 Crack Growth Calculations
. For both sizes of pipe, crack growth calculations for an eleven-month period (December 1983 - November 1984) were performed with the three different values for each of the four major variables. Thus, 81 crack growth cases for each size of pipe were performed. The computer program NUTCRAK (Reference 7) was used for the 28" pipe 1
with assumed 360* cracks and the computer program NUFLAW (Reference 8) was used for the 12" pipe with assumed
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crack lengths of ten times their depths. The results of each case a.re given in Tables 5.2.and 5.3.
Examination of Table 5.2 (28" pipe) reveals the
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following:
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a) The largest predicted crack size after 11 months is 0.74 inch b) The mean predicted crack size is 0.27 inch c) The standard deviation is 0.11 inch-s Due to the large number of crack grosth calculations and the method that was used to select the input variables, the actual mean crack size ( ) can be calculated by.
using the T distribution.
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- X-T < <X+T '
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Where:
Y = sample mean = 0.27 s = sample standard deviation = 0.11 n = number of calculations = 81 T =
value of the T distribution at the appro-priate confidence level and number of degrees of freedom.
With a confidence level of 991 and number of degrees of freedom greater than 29, the actual mean crack size is between 0.24 inch and 0.30 inch.
4 The allowable crack size for a 360* crack in 28" pipe is 63% of the pipe wall (0.79 inches) per Reference 1 i,
(stress ratio = 0.6). All calculated crack sizes as of D -
November 1984 are less than the allowable. The mean j' calculated crack size and the three standard deviation
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extreme crack size are below the allowable crack size. -
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. Examination of Table 5.3 (12" pipe) reveals the t-U following: '
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a) 17 of the 81 cases result in a through wall crack within eleven months. Two additional cases result I. in a crack larger than the allowable depth (47% of
- wall) for a 360* crack within eleven months. It should be noted that the prediction of a through
,; wall crack does not indicate a safety concern for several reasons. First, a conservative initial 1, ~
i, crack was postulated to exist and t'o exist in combination with the worst case values of the other
! major variables. Second, Brunswick Unit I has 4 instituted augmented leakage monitoring. Third, high growth rates can only occur adjacent to welds with high applied bending stress. Such bending stress will cause significant asymmetry, thus,
), assuring leak before break.
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! b) 16 of the 19 cases that result in an unacceptable
- j 3 crack occur with I 'the upper bound crack growth law. The remaining 3 cases result from a '
combination of the highest applied stress coupled with the largest initial defect or the worst case .
- residual stress.
-[I t c) The remaining 62 cases result in a maximum crack t, depth after 11 months (November 1984) of 0.26 inch i.
with a mean value of 0.10 inch.
t CPL-17-103 15 Revision 0 !
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. Thus, based on the above and on the fact that
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approximately 10 percent of the 12-inch and smaller ri welds examined at Brunswick Unit 2 were cracked in December 1983, the number (N) of welds which would be expected to have cracks of depth greater than that permitted by Reference 1 can be~ defined with the follouing equation:
N' = 0.026N' N =
.10(ff)
Where:
5 N' = Number of 12 inch and smaller welds Since N' is approximately equal to 74, two welds in the 12 inch and smaller piping could have flaws larger than those allowed by Reference 1. Since Unit I has operated for 8300 fewer hours than Unit 2, it is likely that no unacceptable cracks will exist in Unit 1 by November 1984.
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CPL-17-103 16 Revision 0 rtut_ec_h
, Table 5.1
, CIRCUMFERENTIAL CRACK DEPTHS Maximum Crack Depth Weld Number for Pipe Diameter of -
< 12" > 12" 2-B32-28-A-8 17%
. 2-B32-28-A-14 20%
y, 2-B32-28-A-4 19%
2-B32-28-B-4 11%
. 2-B32-28-B-5 22%
2-B32-28-B-3 16%
2-B32-28-A-13 19%
v 2-B32-28-B-9 17.6%
l-B32-28-A-14 20%
l-B.32-28-B-8 30%
!~ 2-B32-22-AM-5 20%
2-B32-22-BM-1 16%
2-B32-12-G-4 14%
,3 2-B32-12-K-3 ,
- 5%.
.3 2-B32-12-J-3 11%
.' 2-B32-12-K-2 11%
2-B32-12-J-2 12%
~ 2-G31-6-10 13%
2-G31-6-15 16%
'l 2-G31-6-16 8% -
, Average Depth (X) 11.2% 19.0% .
[ Standard Deviation (S) 3.45% 4.48% ,
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l Table 5.2 28" PIPE CRACK GROWTH RESULTS Initial Weld Final Crack Crack Residual Applied Crack Growth ' Depth in - i
, Depth stress stress Law 11 months Case (inches) (psi) (inches)
'b 1 .13 Cons. 15,000 Upper Bound . 3918 2 .24 . 5478 3 .35 . . 7390
- _ , 4 .13 Best *
. 2054 5 .24 . 2790 6 .35 . 3583 7 .13 Opt. . 1532 8 .24 . 2364 9 .35 No Growth
.13 i
. 10 Cons. 8,300 . 2518
- 11 .24 . 3529 12 .35 . 4387 13 .13 Best . 1600 14 .24 . 2437 15 .35 No Growth 16 .13 Opt. . 1332 17 .24 No Growth i 18 .35 No Growth
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19 .13 Cons. 6,400 . 2268 7 '
20 .24 . 3239 21 .35 .
. 4064 22 .13 Best .
. 1512 23 .24 .
. 2393 l' 24 .35 No Growth-
.! 25 .13 ,
Opt. . 1298 26 .24 No Growth
,. 27 .35 No Growth
% 28 .13 Cons. 15,000 Best Estimate .1958 29 .24 .
. 3233 30 .35 . 4378 .
. 31 .13 Best . 1517
32 .24 . 2508 33 .35 . 3493
., :. 34 .13 Opt. . 1348
' [. '
35 .24 . 2361 36 .35 -
No Growth 37 .13 Cons. 8,300 . 1620 ,
f .' 38 .24 . 2740 l 39 . 35 . 3752 40 .13 Best . 1356
, 41 .24 . 2385 i
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Table 5.2 28" PIPE CRACK GROWTH.RESULTS
, (Concluded)
Initial Weld Final Crack Crack Residual Applied Crack Growth Depth in Depth Stress Stress Law 11 months
(- Case (inchos) (psi) { inches) 42 .35 No Growth 43 .13 Opt. .1277 j 44 .24 No Growth 45 .35 No Growth
. p, 46 .13 Cons. 6,400 .1552
-r
.47 .24 .
.2648 48 .35 .3652
. 49 *
.13 Best .1512 50 .24 6,400 .2370 51 .35 No Growth 52 .13 Opt. .1266 53 .24 No Growth 54 .35 No Growth 55 .13 Cons. 15,000 Lower Bound .1488
. 56 .24 -
.2671
, 57 .35 -
.3779
.; 58 .13 Best .1349 59 .24 -
.2416
, 60 .35 .3466 4'
61 .13 Opt. .1287 62 .24 *
.2360 63 .35 .
." No Growth 64 .13 Cons. 8,300 .1381
. 65 .24 .
.2500 66 .35 .3563 67 .13 Best .1293 68 .24 .2369 69 .35 '
No Growth 70 .13 Opt. .1260 71 .24 No Growth 72 .35 No Growth 73 .13 Cons. 6,400 .1358 74 .24 .2467 75 .35 .3525 76 .13 Best .1282 77 .24 .2364 78 .35 No Growth
- l 79 .13 Opt.
80
. 1256
.24 No Growth 81 .35 No Growth i
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Table 5.3
. 12" PIPE CRACK GROWTH RESULTS Initial Weld Final Crack Crack Residual Applied Crack Growth Depth in Depth Stress Stress Law 11 months Case (inches) (psi) (inches) 1 .025 Cons. 18,800 Upper Bound thru 6.3 mo.
2 .064 thru 3.6 mo.
3 .10 thru 2.4 mo.
4 .025 Best thru 7.8 mo.
^
5 .064 thru 4.4 mo.
6 .10 thru 2.9 mo.
7 .025 Opt. .180 8 .
.064 thru 7.2 mo.
9 .10 thru 4.6 mo.
10 .025 Cons. 11,000 .255 11 .064 . thru 7.2 mo.
12 .10 thru 4.9 mo.
13 .025 Best .135 14 .064 thru 9.3 mo.
15 .10 thru 6.3 mo.
- 16 .02'S Opt. .060
.064 17 .164 18 .10 .353
, 19 .025 Cons. 7,500 .135 L
20 .064 ' thru 10.0 mo.
21 .10 , thru 6.9 mo.
22 .025 Best *
.085 23 .064 .244 li,; 24 .10 -
thru 9.2 mo.
25 .025 Opt. .045
.sc 26' .064 . .119 27 .10 . .198 28 .025 Cons. 18,800 Best Estimate .085 29 .064 .304 30 .10 , -
thru 7.9'mo.
31 .025 Best .065 32 .064 .199 qn 33 .10 thru 9.7 mo..
34 '.025 Opt. '
.040 35 .064 .124 36 .10 .223 1' 37 .025 Cons. 11,000 .055 tj 38 .064 .129 39 .10 .243
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Table 5.3 12" PIPE CRACK GROWTH RESULTS (Continued)
! Initial Weld Final Crack Crack Residual Applied Crack Growth Depth in Depth Stress Stress Law 11 months cx j Case (inches) (psi) (inches) 40 .025 Best . 040
. 41 .064 . 109 42 .10 . 183 43 .025 Opt. . 035 44 .064 . 084
! !- 45 .10 . 143 46 .025 Cons, 7,500 . 040 47 .064 .114 48 *
.10 . 178 49 .025 Best . 040 50 .064 . 094 51 .10 . 153 52 .025 Opt. . 030 53 .064 . 079 54 .10 . 123
' ;' 55 .025 Cons. 18,800 Lower Bound . 040 56 .064 . 104 57 .10 . 188 58 .025 Best . 035
- , 59 .064 . 094 i+ 60 .10 . 158 61 .025 Opt. .
.035 62 .064
. 084
, 63 .10 , . 133 64 .025 Cons, 11,000 .035 e 65 .064 .084
'e 66 .10 .138 i 67 .025 Best .
.030 68 .064 .079 T
- 69 .10 .128
, 70 .025 Opt. -
.030 71 .064 .074
, 72 .10 .118
.;4' 73, .025 Cons. 7,500 .030 -
74 .064 . .079 75 .10 ;128
,'? 76 .025 Best ,030 77 .064 .074 78 .10 .123
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Table 5-3 28" PIPE CRACK GROWTH RESULTS, e
(Concluded)
Initial Weld Final Crack Crack Residual Applied Crack Growth Depth in Depth Stress Stress Law 11 months
- Case (inches) (psi) (inches) 79 .025 Opt. .030 80 .064 .069 81 .10 .'113 U
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6.0 REFERENCES
- 1. ASME Boiler and Pressure Vessel Code,Section XI,
, Paragraph IWB-3640, 1983 Edition, Winter 1983
- t. .
Addenda.
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- 2. NUTECH Report CPL-13-104, Revision 1, Design Report for Weld Overlay Repairs at Brunswick Steam Electric Plant, Unit 2.
- 3. NUTECH Report CPL-13-103, Revision 0, Design Report for Recirculation System Weld Overlay Repairs at Brunswick Steam Electric Plant, Unit 1.
- 4. CNSI Meeting on the Regulatory Basis for Actions on BWR Pipe Cracks, February 7-9, 1984, " Analysis of the Remaining Life of Flawed Piping Weldments in BWRs," by William Shack.
' 5. General Electric Letter G-KB1-1-193, December 30, 1981, " Transmittal of GE Design' Memo 170-17 Revision 1, " Seismic Reevaluation of Recirculation Piping System for Brunswick Units 1 and 2".
- 6. EPRI Report NP-2472 Volume 2, Section H-8, July 1982.
3 7.- NUTECH Computer Program NUTCRAK, Revision 2.0.2, December 1983, File No. 08.039.0005.
- 8. NUTECH Computer Program NUFLAW, Revision 0,
[ November 1983.
Growth Calculations," NUTECH Internal Memo HLG . 001, January 10,1984.
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