ML20129H546
| ML20129H546 | |
| Person / Time | |
|---|---|
| Site: | Byron, Braidwood, 05000000 |
| Issue date: | 06/30/1985 |
| From: | COMMONWEALTH EDISON CO. |
| To: | |
| Shared Package | |
| ML20129H533 | List: |
| References | |
| NUDOCS 8507190233 | |
| Download: ML20129H546 (22) | |
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COMMONWEALTH EDISON COMPANY BYRON STATION, UNITS 1 AND 2 BRAIDWOOD STATION, UNITS 1 AND 2 VALUE IMPACT OF IMPLEMENTING " LEAK-BEFORE-BREAK" AND ELIMINATION OF ASSOCIATED PIPE WHIP RESTRAINTS AND JET DEFLECTORS ON THE RCS PRIMARY LOOP A
JUNE 1985 0507190233 850620 PDR ADOCK 05000454 P
PDR a
e VALUE IMPACT OF IMPLEMENTING " LEAK-BEFORE-BREAK" ON RCS PRIMARY LOOP AT BYRON AND BRAIDWOOD STATIONS I.
Introduction II.
Value Impact Summary Conclusions III.
Consideration of the Benefits Versus the Impacts of Implementing Leak-Before-Break Attachment A Risk increase associated with elimination of protection from dynamic effects associated with pipe breaks a.
public health b.
occupational exposure (accidental)
Attachment B Occupational exposure to remove Byron Unit 1 pipe whip restraints and jet deflectors Attachment C Reduction in occupational exposure (operational) due to elimination of pipe whip restraints and jet deflectors Attachment D Value impact of implementing
< 6043b*
A
I.
Introduction Generic Letter No. 84-04 provided the NRC safety evaluation concluding that an acceptable technical basis exists so that the blowdown loads resulting from double-ended pipe breaks in the RCS primary loop need not be considered as a design basis, provided that certain conditions can be met for plants such as our Byron and Braidwood Stations.
The generic letter indicated that Applicants may request cxemptions from the requirements of GDC-4 with respect to blowdown loads from discrete breaks in the RCS primary loop if they can demonstrate the cpplicability of the modeling used and conclusions reached in the generic Westinghouse analyses.
In a letter dated September 17, 1984, Commonwealth Edison provided the requisite plant specific analyses to demonstrate the cpplicability of the Westinghouse generic conclusions to our Byron and Braidwood Stations.
That submittal technically supported the implementation of " leak-before-break" an these units based on the integrity of the primary piping.
Upon review of our submittal, the NRC ctaff requested that we provide a safety balance evaluation of the consequences of eliminating the protective devices currently employed in cur design to mitigate the dynamic effects associated with postulated breaks.
The purpose of this submittal is to further pursue our exemption request and provide our assessment of the value impact of implementing
" leak-before-break" on the RCS primary loops at Byron and Braidwood when considering the resultant public and occupational exposures due to climination of the associated pipe whip restraints and jet deflectors.
The following value impact analysis utilizes methodology consistent with that utilized in Generic Letter No. 84-04 and confirms that the safety benefits outweigh the impacts of implementing
" leak-before-break" on our units.
Plant specific data and certain data x,,si contained in Generic Letter No. 84-04, along with various assumptions have been used to perform the value impact analysis for Byron and Braidwood.
The c. valuation has been performed in terms of increased public and occupational exposure attributable to elimination of the protection provided for dynamic effects associated with postulated breaks in the RCS primary loop given an accident, compared to the reduction in cccupational exposure during operations due to improved access and increased work efficiency associated with elimination of the pipe whip restraints and jet deflectors.
However, in contrast to Generic Letter No. 84-04, our analysis results are provided on a per plant year basis cnd not integrated over the expected 40 year plant life.
_2_
l 4
II.
Value Impact Summary Conclusions The value impact analysis results are summarized below.
The cnnualized nominal dose estimates clearly indicate that implementation of cleak-before-break" on the RCS primary loop piping of each of our Byron cnd Braidwcod units is justifiable when considering public and cccupational exposure (both operational and accidental) over the 40 year life of these units.
Detailed results are contained in Attachment D.
Benefit Impact Annual Reduction in Annual Increase in Exposure Per Unit Exposure Per Unit (man-rem /yr)
(man-rem /yr)
Byron Unit 2 Eraidwood Units 1 and 2 12.5 2.8E-2 Byron Unit 1 12.5 8.6 Additional benefits derived from removal of the pipe whip restraints and jet deflectors include the ability to more completely insulate the RCS primary loop piping.
As such, Icwor containment s_,M temperatures should be achievable thus benefiting the thormal aging process of equipment.
This advantage has not been directly factored into the evaluation. a
III.
Consideration of the Benefits Versus the Impacts of Implementing Leak-Before-Break Attachment A provides the annualized estimate of increased cxposare to the public and plant personnel should a major accident occur cfter removal of the RCS primary loop pipe whip restraints and jet deflectors associated with leak-before-break.
This analysis is consistent with the methodology utilized in Generic Letter No. 84-04.
Attachment B provides the total and annualized estimate of increased exposure to plant personnel for removing the Byron Unit 1 primary loop pipe whip restraints and jet deflectors.
(In contrast to the annualized exposures discussed in Attachments A and C, the estimated exposure to remove the Byron Unit 1 hardware is a one-time exposure cvent.
In order to assess this one-time exposure with the annual cxposures discussed in Attachments A and C, we have annualized the Byron Unit 1 hardware removal exposures for comparison purpoces.)
The majority of the man hours and resultant exposures are attributable to removal of the jet deflectors.
Expected Byron Unit 1 exposure rates of 45mr/hr for cctivities near piping surfaces and Smr/hr for activities at the floor level have been assumed based on our experiences at Zion Station.
These Cstimates are compcrable to the exposure rates utilized in the generic letter and do assume the application of shielding material to the primary piping in the vicinity of restraint removal activites.
The man-rom cxosures for shielding installation and removal as well as insulation removal and reinstallation have been included and are based upon our Zion Station 1984 actual and 1985 estimated outage exposure data for shielding cnd insulation work.
Grinding activities after cutting have been Cinimized or eliminated where practicable to do so.
M Attachment C provides the annualized estimate of reduced cxposure to plant personnel during operations due to improved access and increased work efficiency once the pipe whip restraints and jet deflectors have been eliminated.
The estimated annual exposures by various work functions have been taken from the Byron /Braidwood FSAR Table 12.4-3.
The percentage of these annual exposures taken to be within containment are based upon our Zion Station experience.
Also, one half of the special maintenance is assumed to be attributable to steam generator activities.
Although difficult to quantify, we have assigned a
conservative values for improved access and increased work efficiency.
Attachment D provides a composite tabulation of the data contained in Attachments A, B and C.
In this format, the annualized benefit of implementing leak-before-break in terms of reduced operational cxposures is compared to the annualized impact of implementing leak-before-break in terms of increased exposures, both accidertal and the occupational exposure to remove the hardware from our operating Byron Unit 1.
ATTACHMENT A ESTIMATE OF RISK INCREASE ASSOCIATED WITH ELIMINATION OF PROTECTION FROM
' DYNAMIC EFFECTS ASSOCIATED WITH PIPE BREAKS IN RCS PRIMARY LOOP.
A.
Public Health Generic Letter No. 84-04 (Reference 1) has beet. used as a basis for calculating the potential increase in offsite dose to the general public resulting from employment of " Leak-Before-Break" and elimination of special design considerations for pipe breaks in the RCS primary coolant loops.
However, several changes were necessary to calculate dose estimates applicable to our Byron and Braidwood Stations.
The following basis was used for the calculation:
1.
Byron and Braidwood Stations are four loop Westinghouse PWRs each with two units.
Because the Reference 1 estimates are given in terms of one unit with two loops, adjustments have been made to consider the increased number of potential break locations in a four loop unit.
2.
The most significant site specific effect is population density.
Reference 1 assumed the U.S.
average of 340 people per square mile with a uniform population density.
As stated in the Byron /Braidwood FSAR and Environmental Report, in the year 2020, Byron is predicted to have a corresponding population density of 193 people per square mile in the o to 50 mile radius zone while Braidwood is predicted to have a population density of 653 people per square mile in the o to 50 mile radius zone.
The Braidwood population density has been used throughout this calculation.
As a consequence, the resulting offsite doses are conservative for Byron by a factor of approximately 3.4.
3.
The assumption of uniform population density and a 50-mile radius release model was used for this calculation.
Based on area, this would indicate that 96% of the population was located in the 10 to 50 mile radius segment.
In actuality, approximately 97.9% and 99.4% of the population respectively is in thia zone at Byron and Braidwood.
This increases the conservatism of this calculation.
4.
Reference 1 used the typical midwestern site meteorology of the Byron and Braidwood sites and is therefore directly applicable.
A.1 J
Reference 1 calculated the increase in risks associated with a large LOCA using the guidelines in WASH-1400 assuming no protection from the dynamic effects of pipe rupture.
As used in Reference 1 and throughout this submittal, the term " plant" means a single unit.
For a two loop plant, the nominal risk increase from a double-ended guillotine (DEG) large LOCA within the reactor cavity from Reference 1 was estimated to be 6E-3 man-rem /py (man-rem per plant year).
Adjusting for the number of loops (4 vs 2) and the difference in population density (653 vs 340), the Braidwood nominal risk estimate is:
4/2 X 653/340 X 6E-3 = 2.3E-2 man-rem /py Similarly from Reference 1, the nominal risk from a DEG large LOCA outside the reactor cavity was estimated to be 2E-4 man-rem /py.
The Braidwood nominal risk estimate is:
4/2 X 653/340 X 2E-4 = 7.7E-4 Therefore, the combined Braidwood nominal increase in risk estimate from DEG large LOCAs both within and outside of the reactor cavity is:
2.3E-2 + 7.7E-4 = 2.4E-2 man-rem /py The upper increase in risk estimate is calculated in Reference 1 with a procedure similar to that utilized for the nominal risk estimate, but based on a more conservative estimate of the probability of a large LOCA and core molt.
The upper estimate in Reference 1 is 0.1 man-rom /py with no adjustments required for the number of loops per plant because this frequency is por plant year.
Adjusting for the difference in population density, the Braidwood upper increase in risk estimate is:
I 653/340 X 0.1 = 0.2 man-rom /py The lower increase in risk estimato is assumed to be 0.
The increases in risk to the public as determined above are tabulated as follows:
Risk Increase (man-rem /py)
Nominal Estimate 2.4E-2 Upper Estimate 0.2 Lower Estimate O
A.2
D.
Occupational Exposure i
An increase in occupational exposure can be calculated as the increase in core melt frequency multiplied by the occupational exposure expected to occur as a result of a major accident.
Reference 1 calculated an increase in core melt frequency by summing the contribution from the breaks inside the reactor cavity and the breaks outside the reactor cavity, and then adjusting for the number of loops.
For Byron and Braidwood, the nominal core melt frequency increase would be:
4/2 X (9E-8+0.2X(3E-6/250)) = 2E-7 events /py The upper estimate of 2E-6 events /py from Reference 1 is directly applicable because it is per plant year and is not dependent upon the number of loops.
A lower bound estimate of O is assumed.
These estimates are then used with cleanup and decommissioning dose estimates from NUREG/CR-2601 (Reference 2) to give an estimate of occupational exposure increase per plant year.
The dose estimates are given in two parts.
The first is immediate occupational exposure (Dro) during the span of the event and its short term control.
The second is the long-term occupational exposure (DLTO) associated with the cleanup and recovery from the accident.
The increase in occupational exposure per plant year (Dog) is calculated as follows:
Dog = P(Dro +LLTO) where Increase in occupational exposure per plant year Dog
=
Increase in core melt frequency P
=
Immediate occupational exposure Dgo
=
DLTO
= Long-term occupational exposure A.3
The results of the calculations are shown below.
Uncertainties are conservatively propagated by the use of upper bound D o and upper i
bound DLTO-P D o (a)
DLTO (a)
Dog i
(events /
(man-ren/
(man-rem /
(man-rem /
plant-vr) event) event) plant-vr)
Nominal Estimate 2E-7 lE+3 2E+4 4.2E-3 Upper Estimate 2E-6 4E+3 3E+4 6.8E-2 Lower Estimate 0
0 1E+4 0
(a) Based on cleanup and decommissioning estimates contained in Reference 2
References:
Ceference 1:
NRC Generic Letter 84-04, February 1, 1984 i
Reference 2:
NUREG/CR-2601 (Murphy, 1982) 6043b*
A.4 l
1 l
BYRON-FSAR TABLE 2.1-2 (Cont'd)
()
2020 RADIfLINTERVAL SECTOR (mi)
DESIGNATION 10-20 20-30
(
30-40 40-50 0-50 N
5,137 5,583 14,097 10,970 37,598 T
NNE 84,721 46,388 92,955 109,909 337,182 NE 213,715 53,284 9,628 29,153 307,853 ENE 9,258 33,713 14,386 51,054 111,272 E
2,376 10,157 19,621 64,028 97,381 ESE 2,403 69,315 29,405 30,811 132,724 SE 21,495 2,877 6,332 46,088 77,214 SSE 2,066 2,726 16,843 6,209 28,996 S
4,017 6,259 4,571 16,583 32,284 SSW 13,049 5,460 4,599 8,299 35,355 SW 12,475 45,376 18,220 10,228 89,417 WSW 5,247 4,740 9,088 44,712 67,409 W
1,989 4,278 7,209 13,407 30,684 WNW 3,617 5,650 3,402 6,496 20,153 NW 1,773 51,748 8,275 7,753 71,182 NNW 4,821 5,269 11,577 15,632 37,434 Sum for Radial Interval 388,159 352,823 270,208 471,332 1,514,138 Cumulative Total To Outer Radius 419,775 772,598 1,042,806 1,514,138 1,514,138 Average Degsity (people /mi ) In Radial Region 412 225 123 167 193
}
2.1-24
BRAIDWOOD-FSAR AMENDMENT 42 MAY 1983 3
TABLE 2.1-3 (Cont ' d)
J PREDICTED 2020 POPULATION SY ANNULAR SECTORS DISTANCE RANGE FROM SITE (NILES) 10.0 20.0 30.0 40.0 10.0 0.0 TO TO TO TO TO TO SECTOR 20.0 30.0 40.0 50.0 50.0 50.0 N
27636 31225 209902 279945 548708 550758 NNE 20352 165147 304659 851067 1341225 1344634 NE 5974 51172 422941 1779099 2259186 2265561 ENE 1507 9665 171899 300466 483537 486260 E
1155 5149 9267 27773 43344 44637 ESE 34042 51349 11379 5025 101795 102201 SE 4215 7244 2860 10447 24766 24995 SSE 2357 2175 5966 2525 13023 13892 S
1449 1703 2905 2365 8422 9286 SSW 921 1472 6965 2169 11527 12724 SW 5779 2061 17175 6539 31554 34398 WSW 650 2673 22333 5654 31310 32135 W
1178 2623 10117 32749 46667 47865 WNW 2497 11326 20044 4667 38534 38942 s
NW 13028 4592 15843 5162 38625 43771 NNW 2370 8920 38954 16856 67100 72675 Sum for radial interval 125110 358496 1273209 3332508 5089323 5124734 Cummulative total to outer radius 160521 519017 1792226 5124734 5124734 Average density 2
(people /m1 ) in radial region 133 228 579 1179 675 653 4
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Cyron ER-OLS TABLE 2.1-4 (Cont'd) 2020 SECTOR RADIAL INTERVAL (miles)
DESIGNATION 10-20 20-30 30-40 40-50 0-50 N
5,137 5,583 14,097 10,970 37,598 NNE 84,721 46,383 92,955 109,909 337,182 NE 213,715 53,284 9,628 29,153 307,853 ENE 9,258 33,713 14,386 51,054 111,272 E
2,376 10,157 19,621 64,028 97,381 ESE 2,403 69,315 29,405 30,811 132,724 SE 21,495 2,877 6,332 46,088 77,214 SSE 2,066 2,726 16,843 6,209 28,996 S
4,017 6,259 4,571 16,583 32,284 SSW 13,049 5,460 4,599 8,299 35,355 SW 12,475 45,376 18,220 10,228 89,417 WSW 5,247 4,740 9,088 44,712 67,409
)
W 1,989 4,278 7,209 13,407 30,684 WNW 3,617 5,650 3,402 6,496 20,153 NW 1,773 51,748 8,275 7,753 71,182 NNW 4,821 5,269 11,577 15,632 37,434 Sum for Radial Interval 388,159 352,823 270,208 471,332 1,514,138 Cumulative Total to Outer Radius 419,775 772,598 1,042,806 1,514,138 1,514,138 Average Density (persons /mi2) in Radial Region 412 225 123 167 193
)
2.1-28
()
d-TABLE 2.1-3 (continued) 2020 RADIAL INTERVAL (miles)
Sector Designation 10-20 20-30 30-40 40-50 0-50 N
27,636 31,225 209,902 279,945 550,758 NNE 20,352 165,147 304,659 851,067 1,344,634 NE 5,974 51,172 422,941 1,779,099 2,265,561 ENE 1,507 9,665 171,899 300,466 486,260 E
1,155 5,149 9,267 27,773 44,637 ESE 34,042 51,349 11,379 5,025 102,201 SE 4,215 7,244 2, 86 0 10,447 24,995 SSE 2,357 2,175 5,966 2,525 13,892 g
S 1,449 1,703 2,905 2,365 9,2 86 g
SSW 921 1,472 6,965 2,169 12,724 g
m SW 5,779 2,061 17,175 6,539 34,398 g
- g L
WSW 650 2,673 22,333 5,654 32,135
-4 W
1,178 2,623 10,117 32,749 47,865 f
WNW 2,497 11,326 20,044 4,667 38,942 o
NW 13,028 4,592 15,843 5,162 43,771 6
NNW 2,370 8,920 38,954 16,856 72,675 Sum for Radial Interval 125,110 358,496 1,273,209 3,332,508 5,124,734 Cummulative Total to Outer Radius 160,521 519,017 1,792,226 5,124,734 5,124,734 Average Density (people /m1 2) in Radial Region 133 228 579 1,179 653 si
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ATTACHMENT B 1
l ESTIMATED OCCUPATIONAL EXPOSURE TO REMOVE BYRON UNIT 1 PRIMARY LOOP PIPE WHIP RESTRAINTS AND JET DEFLECTORS 1)
PIPE leIIP RESTRAINT AND JET DEFLECTOR ACTIVITIES:
l DEVICE /
ESTIMATED MANHOURS 9 EXPOSURE PER NUMBER OF
-TOTAL EXPOSURE ACTIVITY 45MR/HR SMR/HR DEVICE (MAN-REM)
DEVICES (MAN-REM)
' CROSS OVER (R4,RS) 1.2 8
9.6 a) RIGGING 15 5
b) CUTTING 20 c) REMOVAL 72 l
d) GRINDING 16 SUPER TOWER (R2) 3.0 4
12.0 l
a RIGGING 40 40-b SCAFFOLDING 32 c CUTTING 40 d) REMOVAL 108 e) GRINDING 20 HOOP (R3) 6.1 4
24.4-a) RIGGING 30~
b) SCAFFOLDING 40 c) CUTTING 32 d) REMOVAL 32 20 I
B.1 l
L A
DEVICE /
ESTIMATED MANHOURS 9 EXPOSURE PER NUMBER OF TOTAL EXPOSURE ACTIVITY 45MR/HR SMR/HR DEVICE (MAN-REM)
DEVICES (MAN-kEM)
JET DEFLECTOR (9R2) 70.9 4
283.6 a) RIGGING 48 b) UNBOLT H&V 168 144 TIES c) CUT H&V TIES 144 144 AND LOWER TO EL. 377 d) REMOVE SIDE 260 28 RAILS TO EL. 377 e) REMOVAL OF 216 H&V TIES AND SIDE RAILS f) UNBOLT YOKE 180 g) REMOVE YOKE TO 691 77 EL. 377 h) REMOVAL OF YOKE 144 SUBTOTAL ESTIMATED 329.6 EXPOSURE (MAN-REM) 2)
PROVIDE SHIELDING AS APPROPRIATE 5.0 3)
REMOVE INSULATION AND RE-INSULATE AS APPROPRIATE 10.0 TOTAL ESTIMATED EXPOSURE (MAN-REM) 344.6 ANNUALIZED EXPOSURE OVER 40 YEAR LIFE NOTE: THIS ONE-TIME EXPOSURE IS PRESENTED AS AN ANNUALIZED EXPOSURE FOR COMPARISON ESTIMATED EXPOSURE PURPOSES ONLY.
(MAN-REM /PY) 3.6 B.2 6043b*
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R2 B3 88 R5 B12 1
R4 BYRON /BR AIDWOOD STATIONS FIN AL S AFETY AN ALYSIS REPORT FIGUTE 3.6-19 BREAK AND RESTRAINT LOCATIONS
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_a BYRON /BR AIDWOOD STATIONS FINAL S AFETY AN ALYSIS REPORT FIGURE 3.6-22 JET DEFLECTOR GENERAL ARRANGEMENT
ATTACHMENT C ESTIMATED REDUCTION IN OCCUPATIONAL EXPOSURE DUE TO ELIMINATION OF PRIMARY LOOP PIPE WHIP RESTRAINTS AND JET DEFLECTORS ASSUMED PERCENT -
ESTIMATED ANNUAL (a)
PERCENT OF ANNUAL INCREASE IN IMPROVED ANNUAL REDUCTION OCCUPATIONAL EXPOSURE EXPOSURE WITHIN ACCESS AND INCREASED OCCUPATIONAL PER 2 UNIT SITE CONTAINMENT /SG WORK EFFICIENCY DUE EXPOSURE PER PLANT WORK FUNCTION (MAN-REM)
MAINTENANCE TO REMOVAL (MAN-REM /PY)
- 1. ROUTINE OPERATIONS 65 36 (b) 5 0.6 AND SURVEILLANCE
- 2. ROUTINE MAINTENANCE 300 36 (b) 15 8.1 AND INSERVICE INSPECTION
- 3. SPECIAL MAINTENANCE 300 50 (c) 5 3.8 12.5 NOTES:
(a) TAKEN FROM B/B FSAR TABLE 12.4-3 (b) IN CONTAINMENT EXPOSURE. BASED ON ZION EXPERIENCE (c) ASSUME 1/2 0F SPECIAL MAINTENANCE IS ATTRIBUTABLE TO STEAM GENERATORS 6043b*
J
B/B-FSAR AMENDMENT 40 NOVEMBER 1982 TABLE 12.4-3 (Cont'd )
Byron /Braidwood Estimated Annual Man-rem Routine Maintenance and Surveillance 65 Routine Maintenance and Inservice Inspection 300 Refueling 65 Radwaste Processing and Handling 20 Other 50 l
Special Maintenance 300 TOTAL 800 NOTES:
Exposures given were reported as the sum of individual exposures greater than.500 mrem, except for Zion.
Where the breakdown in the original report was more detailed, categories have been condensed as necessary to obtain the categories given here.
The category "other" includes training, miscellaneous, security, consultants, etc.
Where data was incomplete for one-half of the year, the data was prorated from the other complete half of the year, except for refueling.
NR means "not reported," that is, no data for this or any similar category was reported..
- " Normal surveillance" only was reported.
Data for Surry is not included in the averages, since the steam generator tube failures which resulted in high man-rem exposures at Surry are not expected to occur at Byron /Braidwood, which has a different t. team generator design and an all-volatile chemistry for feedwater conditioning.
)
Estimates are conservative to account for exposures less than 100 mrem which are not generally included in reports of occupa-tional exposure and thus are not included in the averages.
12.4-9
y ATTACHMENT-D VALUE IMPACT PER UNIT OF IMPLEMENTING " LEAK-BEFORE-BREAK" 0N RCS PRIMARY LOOP AND REMOVING ASSOCIATED PIPE WHIP RESTRAINTS AND JET DEFLECTORS 1)
BYRON UNIT 2 AND BRAIDWOOD UNITS 1 AND 2 BENEFIT IMPACT
' REDUCTION IN EXPOSURE NOMINAL NOMINAL INCREASE IN EXPOSURE (MAN-REM /PY)-
ESTIMATE ESTIMATE (MAN-REM /PY)
OCCUPATIONAL EXPOSURE (OPERATIONAL)
- 1. ROUTINE OPERATIONS 0.6 AND SURVEILLANCE
- 2. ROUTINE MAINTENANCE 8.1 AND INSERVICE INSPECTION
- 3. SPECIAL MAINTENANCE 3.8 2.4E-2 PUBLIC HEALTH 4.2E-3 OCCUPATIONAL EXPOSURE (ACCIDENTAL)
ANNUAL REDUCTION 12.5 2.8E-2 ANNUAL INCREASE
- 2) BYRON UNIT 1 BENEFIT IMPACT REDUCTION IN EXPOSURE NOMINAL NOMINAL INCREASE IN EXPOSURE (MAN-REM /PY)
ESTIMATE ESTIMATE (MAN-REM /PY)
TOTAL REDUCTION 12.5 2.8E-2 TOTAL INCREASE (FROMAB0VE)
(FROM AB0VE) 8.6 0CCUPATIONAL EXPOSURE DUE TO REMOVAL 0F UNIT 1 PIPE WHIP RESTRAINTS AND JET DEFLECTORS (ANNUALIZED) i ANNUAL REDUCTION 12.5 8.6 ANNUAL INCREASE D.1 6043b*
I