ML20087M648
| ML20087M648 | |
| Person / Time | |
|---|---|
| Site: | Browns Ferry  |
| Issue date: | 02/29/1984 |
| From: | Thom T TENNESSEE VALLEY AUTHORITY |
| To: | |
| Shared Package | |
| ML20087M644 | List: |
| References | |
| NUDOCS 8403300136 | |
| Download: ML20087M648 (37) | |
Text
.
I i
TENNESSEE VALLEY AUTHORITY DIVISION OF NUCLEAR POWER BROWNS FERRY NUCLEAR PLANT MONTHLY OPERATING REPORT TO NRC February 1, 1984 - February 29, 1984 DOCKET NUMBERS 50-259, 50-260, AND 50-296 LICENSE NUMBERS DPR-33, DPR-52, AND DPR-68 f) fi n -
Submitted by:'
/t 4 FM N
. F Plant Superintendent Y
8403300136 840309 PDR ADOCK 05000259
_R
_PDR f
TABLE OF CONTENTS Ope ra ti o ns S ummary..................
1 Refueling Information....................
3 Significant Operational Instructions..
5 Average Daily Unit Power Level........
12 Operating Data Reports......
15 Unit Shutdowns and Power Reductions.............
18 Plant Maintenance......................
21 Field Services Summary............
31 Addenda.
37 a.
1 Ooerations Summar v February 1984 The following sucmary describes the significant operation activities during the reporting period.
In support of this summary, a chronological log of significant events is included in this report.
There were nine reportable occurrences and no revisions to previous report-able occurrences reported to the NRC during the month of February.
Unit 1 There were four scrams on the unit during the month.
On February 9, during performance of an SI, the reactor scrammed on MSIV' closure due to a bad solenoid.
On February 14, the unit was administratively shutdown with a manual scram. The RHRSW and EECW air elease and vacuum relief valves were found marginally designed.
On February 20, during turbine warming opera-tion; and unit startup, the unit scrammed on high first-stage pressure.
On February 29, the unit automatically scrammed from an unknown cause.
Unit 2 There were two scrams on the unit during the month.
On February 14, the unit was administratively shutdown with a manual scram. The RHRSW and EECW air release and vacuum relier valves were found marginally designed.
On February 22, during rod pull approach to critical, an IRM HI HI scram occurred due to continuous withdrawal of a
high worth rod.
Unit 9 The unit was in cold shutdown the er. tire month for the unit's end-of-cycle.
l.
l 5 refueling outage.
Prepared principally by B. L. Porter.
=
2 Ooerations Su===rv (Continued)
February 1984 I
Fatinue Usane Evaluation The cumulative usage factors for the reactor vessel are as follows:
1 Location Usane Factor Unit 1 Unit 2 Unit 1 J
Shell at water line 0.00598 0.00486 0.00403 Feedwater nozzle 0.28817 0.21103 0.15429 i
Closure studs 0.23477 0.17236 0.13233 i
NOTE:
This accumulated monthly information satisfies Technical 4
Specification Section 6.6. A.17.B(3) reporting requirements.
Common System Approximately 9 25E+05 gallons of waste liquids were discharged containing approximately 1.17E+00 curies of activities.
1 t
w-.-
n a
y r~--
3 Ooerations Summary (Continued)
February 1984 Refueline Information Unit 1 Unit 1 ended its fif th refueling outage on.Tanuary 2,1984. Unit 1 is scheduled for its sixth refueling beginning on or about February 8,1985 with a scheduled restart date of August 27, 1985. This refueling will involve loading 8x8R (retrofit) fuel assemblies into the core, replacing recirculation piping, work on "A" and "B" low-pressure turbita, upgrade hangers and anchors, and environmentally qualify instrumentations.
There are 764 fuel assemblies in the rehetor vessel. The spent fuel stor-age pool presently contains 252 EOC-5 fuel assemblies, 260 EOC-4 fuel assemblies; 232 E00-3 fuel assemblies; 156 EOC-2 fuel assemblies; and 168 EOC-1 fuel assemblies.
The present fuel pool capacity is 3,471 locations.
Unit 2 Unit 2 is scheduled for its fif th refueling beginning on or about August 1,1984 with a scheduled restart date of November 29, 1984. This refueling outage will involve loading additional 8X8R (retrofit) fuel assemblies into the core, finishing the torus modification, turbine inspection, finishing piping inspection, finishing THI-2 modifications;_ post-accident sampling facility tie-ins, core spray change-out,_and feedwater-sparger inspection.
Thore are 764 fuel assemblies in the reactor vessel. At the end of the
-month there were 248 E0C-4 fuel assemblies 353 EOC-3 fuel assemblies,156 EOC-2 fuel assemblies, and 132 E00-1 fuel assemblies in the spent fuel storage pool. The present available capacity of the spent fuel pool is 861 locations.
4 Operations Summarv (Continued)
February 1984 Unit 1 Unit 3 shutdown for its fif th refueling outage on September 7,1983, with a scheduled restart date of August 1, 1984. This refueling involves loading 8X8R (retrofit) assemblies into the core, finishing the torus modifications, postaccident sampling facility tie-in, core spray change-out, finishing THI-2 modifications, turbine inspection, piping inspections for cracks, and changeout of jet pump hold-down beams.
There are O fuel assemblies presently in the reactor vessel. There are
~
248 new fuel assemblies, 764 EOC-5 fuel assemblies, 280 EOC-4 fuel assemblies, 124 EOC-3 fuel assemblies, 144 EOC-2 fuel assemblies, and 208 EOC-1 fuel assemblies in the spent fuel storage pool. The present available capacity of the spent fuel pool is 150 locations.
9
5 Stanificant Ooerational Events i
1 Date Tima Event l-Unit 1 2/1 0001 Reactor thermal power at 97-percent (5), maximum flow, rod limited.
0200 Reactor thermal power at 965, maximum flow, rod limited.
1100 Reactor thermal power at 955, maximum flow, rod limited.
2/2 2204 Commenced reducing thermal power for a control rod 4
I pattern adjustment.
2400 Reactor power' at 705 for a control rod pattern adjustment.
2/3 0010 Control rod pattern adjustment in progress, commenced power ascension.
0500 control rod pattern adjustment complete, commenced
-PCIOMR from 785 thermal power.
2/4 0300 Reactor thermal power at 1005, maximum ficw, rod limited.
1230 Reduced thermal power to 965 to decreased -load line.
t 1300 Commenced power ascension from 965 power.
1330 Reactor thermal power at 1005, maximum flow, rod.
limited.
1800 Reactor thermal power at 995, maximum flow, rod -limited.
2040 Commenced power ascension from 995 power.-
2100 Reactor thermal power at.100%, maximum flow, rod limited.
2350 Commenced reducing thermal power for turbine control valve test and Surveillance ~ Instructions (SI).
t 2/5 0100 Reactor thermal power at 915 for turbine control valve
. test and SI's.
i 0215 Turbine control valve test and Ss complete, commenced.
power ascension.
0300' Commenced PCIOMR from 955 thermal power.
0700 Reactor thermal power at 100% maximum flow, rod limited.
I 2/9 0928-Reactor Scram No.169 frca 1005 thermal power during the performance of SI 4.1. A.10.
When the high-radiation
-trip' signal-was given to MSL' "B", FCV-1-38 went closed (MSIV "C" outboard).
Post event investigation revealed the DC. solenoid was failed on this valve. ' The SI-removed power from the'AC solenoid, allowing the valve to close. -B1/B2: channels were tripped.by the HI RAD '
. signal, and A1/A2. RPS channels tripped when "C"l reactor high-pressure signal. was received following FCV-1-38.
closed...MSL "A" high-flow signalLoccurred nearly coincident with-the 'high-pressure signal, and initiated full MSIV closure.
.a :.;
6 Sinnificant Ooerational Events Date Time Event Unit 1 (Continued) 2/10 0141 Commenced rod withdrawal for startup.
0528 Reactor Critical No. 192.
1040 Rolled turbine / generator (T/G).
1140 Synchronized generator, commenced power ascension.
1730 Commenced reducing thermal power from 56% for "A" recirculation pump motor / generator (MG) set brush replacement.
1900 Reactor thernal power at 46% for "A" recirculation pump, MG set brush replacement.
2033 "A" recirculation pump in service, increasing thermal power.
2050 Commenced reducing thermal power from 56% for "B" recirculation pump.
2200 Reactor thermal power at 43% for "B" recirculation pump MG set brush replacement.
2355 "B" recirculation pump in service, commenced power ascension.
2/11 0100 Reactor power at 66%, holding for turbine control valve test and SI's.
0405 Turbine control valve test and SI's complete, increasing thermal power for control rod pattern adjustment.
0635 Control rod pattern adjustment complete, commenced power ascension, 68% thermal power.
0730 Commenced PCIOMR from 82%. thermal power.
1530 Stopped PCIOMR at 85% thermal power, computer out-of-service, reducing power.
1900 Computer back in service, commenced PCIOMR from 83%
thermal power.
2/12 1230 Reactor thermal power at 98%, ' maximum flow, rod limited.
1800 Reactor thermal power at 975, maximum flow, rod limited.
2100 Reactor thermal power at 965, maximum flow, rod limited.
2/13 0200 Reactor power at 955, maximum flow, rod limited.
0845 Commenced power increase with control rod patter n j
adjustment.
1000 Reactor thermal power at 100%, maximum flow, roc limited.
l 1538 Commenced reducing thermal power for control rod pattern I
adjustment.
1700 Reactor power at 915, increased thermal power for j
control rod pattern adjustment.
1900 Commenced PCIOMR from 94% thermal power.
=.
I i
7
}
l l
Sinnificant Operational Events Date Time Event Unit 1 (Continued) l 2/14 0100 Reactor thermal power at 1005, maximum flow, rod l
limited.
0125 Commenced reducing thermal power for shutdown due to problems with RHRSW air release valves.
t 0245-Reactor Scram No.170 from 47% thermal power for modifications to RHRSW air release valves.
l 1025 Reactor in cold shutdown.
2/21 1800 Modifications and testing complete on RHRSW air release valves, commenced rod withdrawal for startup.
1940 Reactor Critical No. 193
(
2/22' 1010 Reactor Scram (Manual) No.171 from 8% thermal power I
when the high-pressure turbine first-stage pressure i
exceeded 142 psig with the TSV's closed.
The A2 and B1 reactor trip actuators were picked up and initiated the scrac, indicating that the only setpoint of PT-1-81B and 1-91 A (turbine first-stage permissive) were reached.
1500
. Withdrawing control rods for startup.
1935 Reactor Critical No. 194.
2/23-0200 Rolled T/0.
0236 Synchronized generator, commenced power ascension.
2 1600 Commenced PCIOMR from 79% thermal power.
2/24 1230 Reactor thermal power at 925, maximum flow,- rod limited..
- 2/25 2200
. Reactor ' thermal power at 875, maximum flow, 'rmd i
limited, commenced reducing thermal power'for control rod pattern adjustment.
2/ 26 0010
- Reactor thermal power at' 795 for ' control rod pattern i
adjustment,-increasing thermal power.
0150
' Reduced thermal power.from 86% to 83% 'for control rod
. pattern adjustment.
0330 Con.rel rod pattern. adjustment complete, commenced -
PCIOMR from 835 power.
1 2/27 0100 Reactor thermal power _'at 1005, maximum flow, rod
' limited."
-1200 Reac tor tharmallpower at 995,. maximum flow, rod ' limited.
- 2/29.
2311
. Reactor Scram No; 172 from 995 thermal power. It.is
. suspected-that personnel bumped panel 25-6 A causing.the l
- scram,- -
o i
W gy
.s e
n
.s
.h, e
+...a.
e w
8 Stanificant Ooerational Events Date Time Event Unit 2 2/1 0001 Reactor thermal power at 100%, maximum flow, rod limited.
2/3 2330 Commenced reducing thermal power for turbine control valve test and SI's.
2400 Reactor power at 915 for turbine control valve test and SI's.
2/4 0045 Turbine control valve test and SI's complete, commenced power descension.
0046 Reactor power at 93%, holding for SI 4 3. A.2 (Control Rod Exercise).
0355 SI 4 3. A.2 complete, commenced power ascension.
0500 Comenced PCIOMR from 95% thermal power.
0900 Reactor thermal power at 1005, maximum flow, rod limited.
2400 Reactor thermal power at 995, maximum flow, rod limited.
2/7 0900 Reactor thermal power at 985, maximum flow, rod limited.
2/9 0700 Reactor thermal power at 97%, maximum flows, rod limited.
2/11 2210 Commenced reducing thermal power for "A" recirculation pump MG set brush replacement.
2/12 0200 Reactor power at 495, "A" HG set brush replacement in progress.
0218 "A" recirculation pump in service holding for replace-ment of brushes in "B" recirculation pump MG set.
0244 Reactor power at 485, "B" recirculation pump out-of-service for MG set brush repla~ cement.
0510 "B" recirculation pump in service, commenced power ascension.
0635 Reactor power at 80% for STEAR 8211' (HPCI).
0735 Commenced reducing thermal power for SI 4 3.B.1.a (Control Rod Coupling Integrity).
0800 Reactor power at 72% for SI 4 3.B.1.a.
0835 Completed SI 4 3.B.1.a, reducing thermal power for HPCI SI's.
0900 Reactor power at 70% for HPCI SI's.
1025 HPCI SI's complete, commenced power ascension.
1330 Commenced PCIOMR from 72% thermal power.
~ _..
m.
9 l
Sinnificant Ooerational Events Date Time Event Unit 2 (Continued) 2/13 2350 Commenced reducing thermal. Power from 985 for shutdown due to problems with RHRSW air release valves.
2/14 0107 Reactor Scram Manual No.150 from 465 thermal power for modifications to RHRSW air release valves.
1122 Reactor in cold shutdown.
2/21 1800 Modifications and testing complete on RHRSW air release valves, holding up on startup to place unit 2 main transformer in service and take spare transformer out-of-service.
2323 Comenced rod withdrawal for startup.
2/22 0057 Reactor Scram No. 151 from 05 thermal. power on high control rod worth.
0845 Commenced rod withdrawal for startup.
1030 Reactor Critical No. 161.
2225 Holding up on startup due to' condenser low vacuum, reactor power at 225.
i 2333 Reducing thermal power due to condenser low vacuum.
2/23 0130 Reactor power at 95, holding due to condenser low vacuum.
1112 Commenced rod withdrawal for startup..
1155 Rolled main turbine.
1209 Turbine tripped on low vacuum from 105 thermal ~ power.
1213 Rolled main. turbine.
1609'
~ Synchronized generator, commenced power ascension.
2/24 1130 Commenced PCIOMR from 765 thermal power.
1835 Stopped PCIOMR at 845 -thermal ~ power due to problems with "A" recirculation pump.
2030 Reduced ~ thermal-power to 635 when "A" recirculation pump
'MG set ran back to minimum speed.-
2125 Commenced power ascension from 635, "A r-ecirculation pump MO set' limited.
2200 Reactor power at 6 85, holding due to "A"" recirculation
- pump HG set problems (Bailey Controller).
2/25-0045 "A" recirculation pump MG set Bailey. Controller problems -
. resolved, commenced power ascension.
0110 Reactor thermal power at 755 'holdirg'ftr turbine control l
valve test.and SI's.,
i 0200 Turbine-control valve test and SI's complei.e,. commenced _
power ascension.
0230
. Commenced PCIOMR from 885 thermal power.
'1800-Reactor thermal power at 985,- maxis a flow, rod limited.
I 4
i f
_..___m 10 Significant Ooerational Events Date Time Event Unit 2 (Continued) 2/26 1000 Reactor thermal power at 955, maximum flow, rod limited.
1020 Commenced reducing thermal power for SI 4 3.A.2 (CRD exercise).
1030 Reactor power at 86% for SI 4 3. A.2.
1115 SI 4 3. A.2 complete, commenced power ascension.
1140 Reactor thermal power at 95%, maximum flow, rod limited.
i 1200 Reactor thermal power at 945, maximum flow, rod limited.
2/29 2400 Reactor thermal power at 94%, maximum flow, rod limited.
i a
l l
11 i
Stanificant Ooerational Events Date Tim Even Unit 3 2/1 0001 End-of-cycle 5 refuel outage in progress (began September 7,1983).
2/29 2400 End-of-cycle 5 refuel outage in progress.
4 1
12 AVER AGE DAILY UNIT POWER LEVEL DOCKET NO.
50-259 UNIT Browns Ferrv 1 e
DATE 3-1-84 COMPLETED BY T. Thom TELEPHONE 205/729-0834 I
6 -
MONTil Februtry I
DAY AVER AGE DAILY POWER LEVEL DAY AVER AGE DAILY POWER LEVEL IMWe Net)
IMWe Net)
I 1028
-17' g7 2
1014 gg
-18 3
920
-17 l
gg 4
1077
-16 20 s
1064 21
-11 6
'I092 22
_33 7
1085 23 f,67 8
1084 24 ogs 9
424 25 Ron
.10 207 26 968 II 845 i
27 i ny t, 9
12 1037 28 In??
13 1045 29 1043 14 47 30 15
-16 33 16
-1R t-
)
INSTRUCTIONS -
On this format. list the average dails una pimei lesciin MWe Net for each day in the reporting:nonth. Compuie Io
~
the nearest whole megawatt.
- 19f77)
I i
i
-. ::::. : ---- - - - - - - - - - - - - - - - -. = - - - - - - - - - -
-.=:..---.
13 AVER AGE DAILY UNIT POWER LEVEL DOCKET NO.
Sn 9An UNIT RN 9 DATE 1-1-R6 COMPLETED BY T. Thom TELEPHONE 705/720-OR14 b,
I 8
j i
MONT11 Pohrunry DAY AVER AGE DAILY POWER LEVEL DAY AVER AGE DAILY POWER LEVEL (MWe Net)
(MWe-Net) l 1080 37
-8 2
1082 is
-10 3
1082 19
-11 l
4 1059 20
-11 3
1074 2
_11 6
1079 22
-la 7
1061 23 157 8
1059 24 777 t,
9 105R 25 on9 10 1049 26 in9A II
_-.1032 27 1019 l
12 736 33 1013 33 997 29 1n11 14 4
30 15
-11 31 16 n
INSTRUCTIONS On this formai.hst the aserage duh unit power laelin \\lV! Net for e.sch day in the reporting month. Con pute to
~
the nearest whole megawatt.
F1177 )
l y
?
14 AVERAGE D AILY UNIT POWER LEVEL
}
DOCKET NO.
50-296 UNIT 3
DATE 3-1-84 C041PLETED BY T. Thom TELEPHONE 205/729-0834 h
MONTH February i
DAY AVERAGE DAILY POWER LEVEL DAY AVERAGE DAILY POWER LEVEL (MWe Net)
(MWe Net) 37
-2 I
1
-1 2
-2
-3 is 3
-3
-2 4
-1 20
-3 5
-3
-3 23 6
-2
-3 22 7
-2 23
-2 8
-3
-2 34 9
-3 25
-2 10
-1 26 i
-2 II
-3
-3 37 12
-3
-3 2g 13
-3
-3 29 14
-2 30 15
-3 3:
16
-3 t
\\
~
l INSTRUCTIONS On Iliis format.hst the average daily unit p.,wer lesel in Nlwe. Net for each day in the reporting month. Con puie so the nearest wl nle nwgawan.
(9/77) m
15 OPERATING DATA REPORT DOCKET NO.
50-259 DATE _1-1-R4 COMPLETED BY T. Thom TELEPilONE 205/729-0834 OPERATING STATUS
- 1. Unit Name:
Ilrowt19 Ferry -1 Notes
- 2. Reporting Period:
February 1984
- 3. Licensed Thennal Power (MWt):
3293
- 4. Nameplate Rating (Gross MWe):
1152
- 5. Doign Electrical Rating (Net MWe):
1065
- 6. Masimum Dependable Capacity (Gross MWe):
in4R 4
- 7. Masimum Dependabic Capacity (Net MWe):
1065
- 8. If Changes Occur in Capacity Ratings (items Number 3 Through 7)Since Last Report. Give Reasons:
u/A
- 9. Power Level To which Restricted.lf Any (Net MWe):
N/A
- 10. Reasons l'or Restrictions. lf Any:
N/A This Month Yr. to Date Cumulative
- 11. Ilours in Reporting Period 696 1.440 84,002
- 12. Number Of flours Reactor Was Critical 480.85 1.208.53 51.014.65
- 13. Reactor Reserve Shutdown llours 215.15 215.15 6.000.17
- 14. Ilours Generator On Line As1.11 1_111.10 49.848.74
- 15. Unit Rewne Shutdown flours 0
0 0
- 16. Gross Thermal Energy Generated (MWil) 1 16L 1??
? _ 4R R _ 4 6 '.
141.546.643
- 17. Grow Electrical Energy Generated (MWH) 41.%.170...
1_ nns. Rin _
46.651.410
- 18. Net Electrical Energy Generated (MWill 444,294 _
977,541 45,302,868
- 19. Unit Senice Factor 65.1 78.5 59.3
- 20. Unit Availability Factor 65.1 78.5 59.3
- 21. Unit Capacity Factor (Using MDC Net) 59.9 63.7 50.6 2.'. Unit Capacity Factor (Uning DER Net) 59.9 63.7 50.6
- 23. Unit Forced Outage Rate la 4 14.7 23.7
- 24. Shutdowns Scheduled Oser Nest 6 Months (Type. Date,and Duration of Eacht:
- 25. If Shut Down At End Of Report Period. Estimated Date of Startup:
- 26. Units in Test Status iPrior io Commercial Operationi:
Forecast Achieved INI'I AI. CRITICA LITY INITIA L ELECT RICITY COMMERCI\\L OPER A TION 19/77)
16 OPERATING DATA REPORT DOCKET NO.
50-260 DATE 1-1-84 COMPLETED BY T. Thom TELEPHONE 205 /729-0834 OPERAllNG STATUS X. Unit Name:
Browns Ferry 2 Notes
- 2. Reporting Period:
Februnrv 19R4
{f
- 3. Licensed Thermal Power (MWt):
3293
- 4. Nameplate Rating (Gross MWe):
1152
- 5. Design Electrical Rating (Net MWe):
1065
- 6. Maximum Dependable Capacity (Gross MWe):
1098.4
- 7. Masimum Dependable Capacity (Net MWel:
1065
- 8. If Changes Occur in Capacity Ratings fitems Number 3 Through 7) Since Last Report.Give Reasons:
N/A
- 9. Power Lesel To Which Restricted.If Any INet MWel:
N/A
- 10. Reasons For Restrictiom. lf Any:
N/A This Mor.th Yr..to.Date Cumulati,e
- 11. Ilours in Reporting Period 696 1,440 78,943
- 12. Number Of Ilours Reactor Was Critical 494.62 1.149.84 51.114.02
- 13. Reactor Resene Shutdown llours 201.38 290.16 14.190.52
- 14. Ilours Generator On Line 464.97 1.105.14 49.597.98
- 15. Unit Resene Shutdown llours 0
0 0
- 16. Gross Thermal Energy Generated (M%ll) 1.426.819 3.459.852.
143.604.897 17 Gross Electrical Energy Generated (MWill 478;980 1,139.280 47.736.568
- 18. Net Electrical Energy Generated (MWill 464,527 1.106,575 46.365,178
- 19. Unit Senice Factor 66.R 76.7 62.R
- 20. Unit Asailability Factor 66.8 76.7 62.8
- 21. Unit Capacity Factor (Using MDC Net) 62.7 72.2 55.1
- 22. Unit Capacity Factor (Using DER Net) 62.7 72.2 55.1
- 23. Unit Forced Outage Rate 13.2 17.5 24.6
- 24. Shutdowns Scheduled Oser Nest 6 Months (Type. Date.and Duration of Each t:
iniv; 14M anfnni
- 25. If Shut Down At End Of Report Period. Estimated Date of Startup:
~
- 26. Uniss in Test Status (Print to Commercial Operationi:
Forecast Achiesrd INITIA L CRITICA LITY INI TIAL Ell:CTRICITY COMMI:RCI \\ L Opt:R A IlON (4/77 3
':w-= ;. :
=
17 i
OPERATING DATA REPORT DOCKET NO.
50-296 DATE 3-1-84 COMPLETED BY T.
Thnm TELEPilONE 205/729-0834 OPERATING STATUS I. Unit Name:
3 N"I'5
~
- 2. Reporting Period:
February 1984
- 3. Licenwd Thermal Power (MWt):
3293
- 4. Nameplate Rating (Gross MWe):
1152
- 5. Design Electrical Rating (Net MWe):
1065
- 6. Masimum Dependable Capacity (Gross MWe):
1098.4
- 7. Masimum Dependable Capacity (Net MWe):
ins
- 8. If Changes Occur in Capacity Ratings (items Number 3 Through 7) Since Last Report. Give Reasons:
N/A
- 9. Power Level To Which Restricted. If Any (Net MWel:
N/A
- 10. Reasons For Restrictions.If Any:
N/A I
This Month Yr to Date Cumulative i1. Ilours In Reporting Period 696 1440 61,368
- 12. Number Of Hours Reactor Was Critical 0
0 43.087.80
- 13. Reactor Reserve Shutdown llours 0
0 3878.13
- 14. Hours Generator On-Line n
0 42.193.71 j
- 15. Unit Reserve Shutdown flours 0
0 0
- 16. Gross Thermal Energy Generated (MWHI O
O 126,307,711
- 17. Gross Electrical Energy Generated (MWH) 0 0
41.597.620
- 18. Net Electrical Energy Generated (MWH) 0 0
40,375.256
- 19. Unit Senice Factor 0
0 68.8
- 20. Unit Availability Factor 0
0 68.8
- 21. Unit Capacity Factor (Using MDC Net) 0 0
61.8
- 22. Unit Capacity Factor (Using DER Net) 0 0
61.8
- 23. Unit Forced Outage Rate 0
0 16.4
- 24. Shutdowns Scheduled Oser Nest 6 Months (T3 pc. Date,and Duration of Facht:
- 25. If Shut Down At End Of Report Period. Estimated Date of Startup:
August 1984
- 26. Units in Test Status IPrior to Commercial Operationi:
Forecast Achiesed INITIA L CRITICALI TY f
INITIAL ELECTRICITY COMMERCIA L OPER ATION (9/77)
DOCKET NO.
50-259 UNITSIIUTDOWNS ANDPOWER REDUCTIONS UNIT NAME Browns Ferrv 1 DATE t-1-84 COMPLETED BY T Thon REPORT MONTH February TELErtlONE 205-729-0834 br I
=.5 E
1 e.
liCC"5" 5*t
!"g<,
Cause & Corrective j _i i53 N.s Date r_
Event 37 9
g,,;,,,,
('
52
-3
-g 3 c:
3mj Repoir:
mo o
Prevent Recurrence OO 6.
1 270 2/2/84 S
11 Derated for control rod pattern adjustment 271 2/9/84 F
26.20 B
3 Reactor Scram during the performance of SI 4.1.A.10 272 2/14/84 F
199.42 A
2 Reactor Scram for modifications to E
l RilRSW air release valves l
l 273 2/22/84 F
16.43 A
3 Reactor Scram (of f line) when the high pressure turbine first stage j
pressure exceeded 142 PSIG with n
)
+
the TSV's closed
(
Reactor Scram due to possible bumpin, J
(
274 2/29/84 F
0.82 II 3
of panel 25-6A
{
~
I 2
3 4
F: Forced Reason:
Method:
Exhibit G. Instructions S: Scheduled A-Equipment Failure (Explain)
I-Manual for Preparation of Data i
B Maintenance of Test 2-Manual Scram.
Entry Sheets for Licensee C. Refueling
- 3. Automatic Scram.
Evant Report (LERI Fde INUREG-I D Regulatory Restrktion 4-Other (Explain) 0161)
E-Operator Training & License Examination s
f F-Administrative 5
G-Operational Error (Explain)
Estubit 1 - Same Source 19/77)
Il-Other (Explain) l l
l
UNIT SilUTDOWNS AND POWER REDUCTIONS DOCKET NO.
50-260 UNIT NAME DATE 3-1-84 COMPLETED BY T.
Thon REPORT MONTil Fehro,rv g
,E
W 7 M W h's, 3 ~2 3
Y(
Licensee
,E-r, No.
Date g
3g g
j g y' Cause & Corrective Event u?
e Action to jE E
j ;5 g Report :
NV j'
Prevent Recurrence 5
289 2/11/84 F
B Derated for "A"
& "B" Recirculation Pump MG set replacement 290 2/14/84 F
191.83 11 2
Rx Scram for Modifications on RHRSW
^
Air Release Valves and to place main transformer in service and take spare transformer out of service s
e 291 2/22/84 F
39.20 11 3
Rx Scram due to Iligh Control Rod Worth I
~
2 3
4 F: Forced Reason:
Method:
Exhibit G -Instructions S: Scheduled A Equipment Failure (Explain) 1-Manual for Preparation of Data 4
B Maintenance of Test 2-Manual Scram.
. Entry Sheets for Licensee C-Refueling 3-Automatic Scram.
Event Report (LERI File (NUREG-I D Regulatory Restriction 4-Other (Explain) 0161)
E-Operater Training & Ucense Examination 5
e F-Administrative G-Operational Error (Explain)
Exhibit I - Same Source (9/77)
Il-Other (E xplain) l h
A UNITSHUIDOWNS AND POWER REDUCTIONS DOCKET NO.
50-296 UNIT NAME 3
DATE 3-1-84 COMPLETED BY T. Thora REPORT MONTH February TELEPHONE 205/729-0834
. s ":
c i
.=2 _e 7.s x Licensee g r, cause & Corrective ce o
$3 Action to No.
Date g
3g j
,g g y Event 3?
$E E
j 65 g Report :
iE 0
}L Prevent Recurrence b
140
.2/1/84
.S 696 C
4 EOC-5 Refuel Outage Continues (controlled shutdown, 9-7-83) g
'~
,s.
/
I
~
2 3
4 F: Forced Reason:
Method:
Exhibit G Instructions
~
S: Scheduled A Equipment Failure (Explain)
I-Manual for Preparation of Data B Maintenance or Test 2-Manual Scram.
Entry Sheets for Licensee C-Refueling 3 Automatic Scram.
Event Report (LER) File (NUREG-I D-Regulatory Restriction 4 Other (Explain) 0161)
E-Operator Training & License Examination F Administrative 5
G-Operational Error (Explain)
Exhibit I - Same Source i9/77)
Il Other (Explain)
CSSC EQUIPMETIT MECHAi1ICAL MADITENANCE SUltGRY For the Month of Februarv 19 8/4 EFFECT ON SAFE ACTION TAKEN DATE SYSTEM COMPONENT NATURE OF OPERATION OF CAUSE OF RESULTS OF T0' PRECLUDE MAINTENANCE THE REACTOR MALFUNCTION "ALFUNCTION 1 RECURRENCE
'2-15 RHR Servico Air release Remove valves Removed to insta] 1 N/A MR 155281 Water valve 0-ARV and clean
' orifice plate g
Ai release Remove valves Removed to insta] 1 N/A MR 155282 Water valve 0-ARV-23~
and clean orifice plate'-
525 flange RHR Servict Air release Remove valves Removed to instaJ 1 N/
MR 155283 2-15 l Water valve 0-ARV.and clean orifice plate 541 flange 2-15 RER Servic(
Air release' Remove valves Removed to instal 1 N/A MR 155284 Water
'121're 0 mr_?3 nna clann _._
orifice plate 560 flange w
2-15 RHR Servicg Air release Remove valves Removed to insta: 1 N/A MR 155285 Water valve 0-aRV and cican orifice plate 387 flange
'-15 RHR Service Air re1eace Remove valves Removed to insta: 1 N/A MR 155286 Water valve 0-ARV and clean orifice plate 590 flange 2-03 Off-Gas Filter leak Normal age and Leak MR 206890 - Replaced System use gasket 2-05 Off-Gas Replace Personnel error Lube valve closed MR 201603 - Replaced System pump 2-15 RHR Service Orifice. Plates Fabricate None None MR 204663 Water 2-14 RHR Service Orifice Plates Fabricate None None MR 204654 Water e
MECl!ANICAL MAINTEt:ANCE SUFS!ARY CSSC EQUIrMENT For the Month of February 19 84 EFFECT ON SAFE ACTIO:3 TAKEN
~
DATE SYSTEM COMPONENT NATURE OF OPERATION OF CAUSE OF RESULTS OF
'IO PRECLUDE MAINTENANCE
- IHF. REACTOR MALFUNCTION 3%LFUNCTION I RECURRENCE 2-06 IIPCI Servo Actuator Remove and Dirt Sticky servo in mid-Cleaned and replaged inspect servo position servo actuator I
actuator MR 150733 l
l
= *.
.me e.
v G
e t
~
~
MECitANICAL IL\\INTE!aNCE SUlD:ARY CSSC EQUIPMENT For the Month of February 19 84 EFFECT ON SAFE ACIl0N TAKEN MTE SYSTEM COMPONENT ^
NATURE OF OPERATION OF CAUSE OF RESULTS OF 10 PRECLUDE MAINTENANCE Tile REACTOR MALFUNCTION St\\LFUNCTION I RECURRENCE t EECW 3B & D Core Flush Preventive mainte-MR A207660 Spray Pump Room nance l
Coolers 3-CLR-67-0922 e
i
.s.-
O' g
e I
e
\\
~ -
. 0
._,Page.
w BROWNS FERRY NUCLEAR PLANT UNIT BF CISIL 30 Appendix B CSSC EQUIPMENT ELECTRICAL MAINTENANCE
SUMMARY
/,
9/29/82 For the Month of February 19 84 Effect on Safe Action Taken Nature of Operation of Cause.of Results of To Preclude Dato System Component Ma in tenance The Reactor Malfunction Malfunction Recurrence 2/14 CO2 Storag<
0-25-296, Replaced cells None Defective cells None Replaced cells fire pro-0-25-297, 1 through 12 on tection.&
0-25-295, smoke detector MR's A216223 1 purging 1-25-303, panel 0-25-296, A216224 l 3-25-287, 7 through 12 on A216225 3-25-303 0-25-297, 7 A216221 through 12 on A216220 0-25-295, 1 A216222 through 6 on 1-25-303, 7 through 12 on 3-25-251, 7 through 12 on I
w 3-25-303
' - ~ ~
2/19 High-pres-0-HS-026-0002 Replaced upper None Unknown Fire pump running Replaced bearing f
sure fire bearing in B noisy protection fire pump motor MR A261471 1
2/22 Radiation' 0-PMP 090-00B Replaced stack None Bad motor Stack gas sample pump Replaced fuses and monitoring gas sample B running noisy and motor pump B fuses blowing fuses and motor FHt's A257189 A256297 9
.n..
<g
BR0h*SS FERRY N" CLEAR PLANT UNIT 1
i ggg 33
^
CSSC EQUIPMENT ELECTR? CAL MAINTENA';CE SLT!ARY 9/29/82 For the Month of February 19 84 Effect on Safe Action Taken Nature of Operation of Cause.of Results of To Preclude D en System Coc:ponent Maintenance The Reactor Malfunction Malfunction Recerrence 2/16 Diesel 1-BDGG-254-000 : Replaced nylon None Supplied by Broken bolt alerted Replaced nylon j
125VDC bolts, ruts vendor EM of the problem hardware with brassl
& flatwashers with brass FUt A202259
,!/10 Main stear 1-FCV-001-038 Replaced DC None Coil burned out Valve inoperable Replaced coil l
l pilot coil MR A208090 i
l
?/12 Residual 1-MG-074 -1EA Adjusted voltagc None Unknown High voltage reading Adjusted voltage t
r-ani MR A256371 1
!/14 Residual 1-FCV-074-0048 Replaced valve Prevented shut-Unknown Site alert.
Replaced motor, heat motor, replaced down cooling LER EFRO-50-259-84012 bearings, and i
removal bearings on new through the RHR performed EMI 7 l
motor, and per-system formed EMI 7 on MR A208095 new valve and A216024 motor A256599
- /15 Main stean, 1-000-001-MSIV Adjusted isola-None Limit switch LS-3 Relay SAK3D dropped Adjusted limit tion valve limit on FCV-1-26 was out switch.
switch open MR A256251 t
.:/15.
Control 1-FCV-085-039A Adjusted limit None Unknown No annunciation in Adjusted limit rod drive switches on control room when switches scram inlet and inlet and outlet is outlet valves or valves are open MR's A214556 4
E;T llCU's (continuco)
A216607 h, -
r A216606 A256605
_ _ =
N ten--s
-a, w
u BR0',GS FERRY NUCLEAR PLM;I UNIT 2
F OSIL 30 Appendix B L
CSSC EQUIPMENT ELECTRICAL MAINTENANCE SD01ARY gj 97g
)
8 For the Month of February 19 84 Effect on Safe Action Taken Nature of Operation of Cause_of Results of To Preclude Dato System Component Maintenance The Reactor Malfunction Malfunction Recurrence 2/8 Off-gas Panel 25-95 Replaced the None Wrong fuses Blew one fuse Replaced fuses following fuses:
9FU from MIC-30 MR 252188 to ATM-20, 10FU i
from MIN-1 (red pin) to KLM-1/ll 16FU from MIC-3 to ATM-3 I
)
2/9 liigh-pre s-
'5TRB-073-0054 Replaced HPCI None In support of None Replaced ECM box sure cool-ECM box per STEAR 82-11 ant injec-STEAR 82-11 MR 155500 cion 2/12 EB heating 2-XA-064-064B Replaced relay None Unknown None Replaced relay l
and venti-16AK64B 1etion MR 256637 1
2/14 fesidual 2-PMP-074-0005 Replaced test None Burned contact
,2A RilR pump breaker Replaced test i
ueat switch on 2A on test switch
'would not close switch removal RHR pump MR 257072 2/14-High press 2-000-073-0000 l'teplaced ramp None Bad ramp generator Replaced ramp sure cool-generator and None generator o
calibrated new ant
[.
injection F SP generator MR 208060 2/R4 Temperature 2-TR-056-0004 Pulled new None Bad thermocouple Had to manually take Connected spare monitccing thermocouple readings from spare thermocouple cable and termi-thermocouple nated per TACF h3-2-84-088-100-5 i
M f
a l
mamme m
db #
BROtsS FERRY :.!! CLEAR PIE.*T Cili i
EF CISIL 30 Appendix s ELECTRICAL MAINTENANCE SDOMRY
. L CSSC EQUIPMENT.
9/29/82 2
For the Month of February 19 84
\\
Effect on Safe Action Taken Nature of Operation of Cause.of Results of To Precl~ude D^to System Component Maintenance The Reactor Malfunction Malfunction Recurrence (continued) 2/15 Lontrol HCU's 58-35, rod drive 54-27, 54-47, 38-07, 38-51, 30-51, 22-39, 22-55, 18-59, 10-35, 14-47 14-51, 06-43, i
06-27, 02-35, 10-27, 30-59, 46-07, 46-11, 46-31, and
}
w 46-43 j
2/21 Control 1-000-085-0000 Replaced relay None Relay coil burned Fuse failure alarm on Replaced relay I
~
rod drive up panel 9-28 MR A256619 g
i l
j r
=
~
e e
i.t.
P t
1 b.
, (' N.
l
" Page j
"~
~
BR0ic;S FERRY
!'" CLEAR Pl.A';T L' NIT 1
BF O'SIL 20
~
CSSC 'EQUIPMD*T.
ELECTRICAL MAINTENANCE SDNARY 9/29/82 For the Month of February 19 84 Effect on Safe Action Taken Nature of Operation of Cause of Results of To Preclude O
D^to System Component Maintenance The Reactor Malfunction Malfunction Recurrence (continued)
.2/15 Control HCU's 58-35, rod drive 54-27, 54-47, 38-07, 38-51, 30-51, 22-39, 22-55, 18-59, 10-35, 14-47, 14-51, 06-43, 06-27, 02-35, 10-27, 30-59, 46-07, 46-11, 46-31, and l
46-43 M
2/21 Control.
1-000-085-0000 Replaced relay None Relay coil burned Fuse failure alarm on Replaced relay rod drive up panel 9-28 MR A256619 g
I i
O O
I 1.
9 q
eW:..
%4*
I
/
BROWNS FERRY NUCLEAR PLANT UNIT 3
F %
33
~
CSSC EQUIPMENT ELECTRICAL MAINTENANCE SDStARY EE 9/29/82 j
For the Month of February 19 84 Effect on Safe Action Taken Nature of Operation of Cause.of Results of To Preclude D?to
~ System Component Maintenance The Reactor Malfunction Malfunction Recurrence 2/7 Containment 3-FSV-084-008B Replaced valve None Switch was None Replaced switch l
atmosphere open indicating borrowed for use dilution switch on U2 valve FSV84-8B on MR A208083 MR A212245 2/8 CO2 storage,XA-39-68A1 Replaced smoke None Dust Smoke alarm in Replaced smoke fire pro-detector constantly
.I tection &
MR 262205 purging.
8 e
O 4
e 6
5 I
e y
I y
b
.m
d.cc Irt*Ir**ENT AliS TRUME ;I !'AINh!.iNC SC 'AilY For the Month of February 19_84 l
EFFECT ON SAFE ACIlON TAKEN g
rdTE SYSTEM COMPONENT NATURE OF OPERATION OF CAUSE OF RESULTS OF TO PRECLUDE
(
MAINTENANCE IHE REACTOR St\\LFl?:CTIO:I 3'.ti.Ft7:CTION RECURRENCE 2/1
.1 1-:'dt-1-25 A Replace None unknown Loss of Indication Stear 84-07
,/.2/1-1' 2-Lm-85-85A'
' Repair None detector uncoupled Loss of Alarm None fj 2/3 76 1 ANA 76-89
' Replace None bulb burned out Loss of Indication None 2/3' 92 1 APRm Replace None age None None V
2/10l 1
2'Pdis 1-13A Replace None age None None d'
2/11f
'l 1-Pdt-1-25B Replace None unknown Loss of Indication Stear 84-07 5
..2/13 92 2-SRM A-Replace None age None Nonc r
log count. rate v
meter-2/17 92 2-APRm B Replace None age None None meter. function switch 2/23 1
1-Pdt-1-25A.
Valued out, None unknown Loss of Indication Stear 84-07 equalized, and then returned to normal
2/23 l'
1 Pdt-1-25B Replace-None unknown Loss of Indication Stear 84-07 e
31 FIELD SERVICES
SUMMARY
February 1984 Work Synoosis Unit 3 cycle 5 outage activities were reduced during the February report period as a result of the decrease in available manpower resources which was imposed effective January 27, 1984. Major emphasis areas this month have included P0392 CRD scram discharge header modification prefabrication, RHR valve and heat exchanger maintenance as well as torus sandblasting and coating operations.
Ma_1or Work Areas A.
Refuel Floor - The shipments of blade guider, to Peach Bottom were completed during February. Inspection of new fuel was completed on February 22.
Cold proof test of overhead crane was performed on February 29.
B.
Turbine - The unit 3 "C" low-pressure turbine work continued during the month.
Coupling alignment on #1 and #2 was completed on February 29 Coupling #3 is presently being aligned.
C.
Other Mechanical Work -
1.
P0392 CRD Scram Discharge Modification work began during the month (prefabrication work). P0538 Centrol Rod Drive.(CRD) Header Flush Connection Installation - work continued with' 30% of shop prefabrication completed. CRD~ header discharge header work is critical path for unit 3 cycle 5 refueling outage.
2.
Repair work on valve 3-74-67 was begun in February.. The valve stem was found broken in two' places. ' A segment of break area was cutL out for analysis'- Work is continuing.
1 a
32 FIELD SERVICES
SUMMARY
February 1984 Maior Work Areas (Continued)
C.
Other Mechanical Work -
3 Main Steam Relief Valves (MSRV) - Work continued at Wyle Labs.
Awaiting Target Rock to supply list of required rebuild parts so contract change order can be approved.
4.
Main Steam Isolation Valves (MSIV) - Of the eight MSIV's to be evaluated each outage, seven have been tested and four of these require maintenance. The four MSIV's requiring maintenance have been disassembled and are in various stages of poppet decontamination and main seat lapping.
5.
Residual Heat Removal (RHR) heat exchanger work continued during February. Plugging and closing of "D" heat exchanger was completed on February 26.
As of February 29, 76 of 124 plugs were installed in "B" heat exchanger.
6.
Probologging of "A" and "C" string feedwater heaters was completed during the month.
One tube was found to need plugging in each of the A1, A2, and C3 heatars with two tubes found to need plugging in C5 Plugging and closing of "C" string began on February 28.
Probologging-of 3A1 water box began on February 28 and is,50-percent complete.
Some evidence of minor growth in steam erosion areas was reported.
7 Emergency Equipment Cooling Water (EECW) piping wall thickness measurements were made in an effort to determine whether replacement is needed. As of February 29,10 of 16 measurements were made with no significant findings.
33 FIELD SERVICES
SUMMARY
February 1984 Maior Work Areas (Continued)
C.
Other Mechanical Work (Continued) 8.
IHSI - Preparation for IHSI work continued. The 750 MC1 cable installation for power support was completed on February 23 A USQD is needed for the removal of interferences for IHSI.
9 P0709 Valve Replacement for Diesel Generators - Unit 1 and 2 prefabrication work is in progress.
All shop welds are complete and PT is in progress.
10.
P0616 Replace Fittings on Reactor Building Closed Cooling Water (RBCCW) to Recirculation Pump Motors - All work was completed on February 23 11.
PO450 Jet Pump Holddown Beam Changeout - This modification is being considered for deferment, awaiting outcome of UT test by General Electric on March 5.
If test results are satisfactory, jet pump holddown beam changeout contract will be cancelled.
12.
P0612 Installation of 1/2 inch stainless steel flex line for MSRV's continued.
13 P0547 Replace Recirculation Check Valves - Work began on February 27.
14.
Hydraulic Snubbers - 10 of 13 Grinnel snubbers were tested as of February 29.-
15 P0501 Modify Hanger Supports for RFWS-48 -- Work continued dt. ring the month.
16.
P0686_ CRD Rebuild Room Drain Line Work continued during-tre month.
36 FIELD SERVICES
SUMMARY
February 1984 Maior Work Areas (Continued)
C.
Other Mechanical Work (Continued) 17 Local Leak Rate Test (LLRT) - Out of 167 valves requiring LLRT,102 have been tested.
Of the 102 valves, 67 have passed and 35 have failed initial testing.
18.
P0684 Torus Vacuum Breaker Modificaiton - Disassembly and shop prefabrication work continued this month.
D.
Electrical / Instrumentation 1.
Recirculation Motors "A" pump motor was run satisfactorily on February 19 "B" pump motor is ready to run. Motor-generator (MG) set "A" had polarity changed and was run on February 28.
MG set "B" is ready to run.
2.
P0533 Torus Temperature Monitoring Devices - Conduit work continued.
Work plan for sequential eventa recorder is in approval cycle.
3 P0422 Installation of Reactor Protection System cabinets and conduit continued during the month.
4.
P0371 Low-Pressure Coolant Injection modification was completed on February 6 (wrap-up work only - the bulk of this modification was performed on a previous. outage).
E.
Planning and Scheduling:
1.
The main thrust of the planning and scheduling effort this report
- period.has -be en the development of a unit -3 cycle 5 outage ~ schedule
.that reflecte the remaining outate work activities in view of.
significant decreases in craf t 'manpowercover previous otuages. The i
35 FIELD SERVICES
SUMMARY
February 1984 Maior Work Areas (Continued)
E.
Planning and Scheduling:
(Continued) 1.
(Continued) i schedule review indicated on August 1,1984 return to service could be achieved at a 580-man trades and labor headcount given several assumptions - these include:
a.
No additions to the modifications currently scheduled for work l
(modification list dated February 15, 1984). This includes the j
assumption that there will be no significant increase in scope of existing modifications.
b.
EECW piping changeout (L1970) will not be performed (without significant effect on manpower and/or duration requirements).
Additional QC inspectors will be available to support ECN P0392 -
c.
4-l (CRD Scram Discharge Header Modification) work on multiple shifts.
d.
Major LLRT valve failures will nol be encountered.
2.
Other planning staff efforts have included:
a.
Preparation of the unit 2 cycle 5 preliminary outage schedule.
b.
Assimilating data for the unit 1 cycle 5 post-outage report.
c.
Providing recommendations for planning staff changes that would permit a greater level of field support / involvement with regard to staging tools,. materials and equipment as well as other pre-
. Job preparation efforts that would be ' beneficial to the foreman.
'n -
36 FIELD SERVICES
SUMMARY
February 1984 Maior Work Areas (Continued)
F.
Torus:
Torus sandblasting by Williams Contractor continued during February. Other work was as follows:
1.
Torus internal modifications - painting work continued. Work was com-pleted in bays 6 through 13 (except for touchup).
2.
Attached piping and prefabrication work continued in February. Of 377 total supports, 183 are complete.
3 Work began on the new turbine decontamination facility. All old equipment was removed from the room.
The floor is being stripped in preparation to paint.
G.
Administrative:
The O&M budget for January was $3,067,160 and the expenditures were
$2,710,962 with year-to-date budget being $10,840,430 and actual year-to-date expenditures being $12,935,014. The capital budget was $2,799,700 and the expenditures were $1,941,223 with year-to-date budget being $12,155,758 and actual year-to-date expenditures being $8,085,000. Overall budget was
$5,866,860 and the overall expenditures were $4,652,185 with year-to-date budget being $22,996,188 and actual year-to-date expenditures being
$21,020,015.
37 ADDENDUM Attached for insertion in the January 1984 Monthly Operating Report to NRC are corrected pages, including Nuclear Plant Operating Statistics and Unit Outage and Availability (Unit 1).
b h