meteorological program self assessment presented at numug san francisco, ca 2009
TRANSCRIPT
Meteorological Program Self Assessment
Presented at NUMUG
San Francisco, CA
2009
Columbia 10m Wind Vanes
Columbia 10m Temp Probes
75m Instruments
FIRST QUARTER FREQUENCY OF STABILITY CLASS33-Foot Level
0.00%
10.00%
20.00%
30.00%
40.00%
50.00%
60.00%
70.00%
80.00%
A B C D E F G
STABILITY CLASS
PER
CEN
T O
CC
UR
REN
CE
1Q/1996 1Q/1997 1Q/1998 1Q/1999 1Q/2000 1Q/2001
Note unusually high frequency of ‘A’ Stability class in 2001. This is impossible in winter months.
SECOND QUARTER FREQUENCY OF STABILITY CLASS33-Foot Level
0.00%
5.00%
10.00%
15.00%
20.00%
25.00%
30.00%
35.00%
40.00%
45.00%
50.00%
A B C D E F G
STABILITY CLASS
PER
CEN
T O
CC
UR
REN
CE
2Q/2003 2Q/2004 2Q/2005 2Q/2006 2Q/2007
For the 2005 data:67% data recovery from A signals.95% from the B set. These values looks like they ARE from the B set.
High frequency of ‘A’ Stability class in 2005 & 2006. This is possible but not likely.
Temperature Probe Output Shift
59
79
05/0
8/08
14:
45:3
9
05/1
1/08
02:
31:1
6
05/1
3/08
14:
16:5
3
05/1
6/08
02:
02:3
0
05/1
8/08
13:
48:0
7
05/2
1/08
01:
33:4
4
05/2
3/08
13:
19:2
1
05/2
6/08
01:
04:5
8
05/2
8/08
12:
50:3
5
05/3
1/08
00:
36:1
2
06/0
2/08
12:
21:4
9
06/0
5/08
00:
07:2
6
06/0
7/08
11:
53:0
3
06/0
9/08
23:
38:4
0
06/1
2/08
11:
24:1
7
06/1
4/08
23:
09:5
4
06/1
7/08
10:
55:3
1
06/1
9/08
22:
41:0
8
06/2
2/08
10:
26:4
5
06/2
4/08
22:
12:2
2
06/2
7/08
09:
57:5
9
06/2
9/08
21:
43:3
6
07/0
2/08
09:
29:1
3
07/0
4/08
21:
14:5
0
07/0
7/08
09:
00:2
7
07/0
9/08
20:
46:0
4
07/1
2/08
08:
31:4
1
07/1
4/08
20:
17:1
8
07/1
7/08
08:
02:5
5
07/1
9/08
19:
48:3
2
07/2
2/08
07:
34:0
9
07/2
4/08
19:
19:4
6
07/2
7/08
07:
05:2
3
07/2
9/08
18:
51:0
0
08/0
1/08
06:
36:3
7
08/0
3/08
18:
22:1
4
08/0
6/08
06:
07:5
1
Tem
per
atu
re R
ead
ing
s at
245
' (D
eg F
)
-1.00
-0.90
-0.80
-0.70
-0.60
-0.50
-0.40
-0.30
-0.20
-0.10
0.00
0.10
0.20
0.30
0.40
0.50
0.60
0.70
0.80
0.90
1.00
Dif
fere
nce
bet
wee
n t
hes
e tw
o s
ign
als
- D
egre
es F
MET TWR AVG A TEMPERATURE @ 245FT-META65 MET TWR AVG B TEMPERATURE @ 245FT-METB65 META65-METB65
Lightning Strike
Delta T Shift
-4
-2
0
2
4
6
8
10
12
14
16
05/0
8/0
8 14
:45:
39
05/1
1/0
8 03
:14:
49
05/1
3/0
8 15
:43:
59
05/1
6/0
8 04
:13:
09
05/1
8/0
8 16
:42:
19
05/2
1/0
8 05
:11:
29
05/2
3/0
8 17
:40:
39
05/2
6/0
8 06
:09:
49
05/2
8/0
8 18
:38:
59
05/3
1/0
8 07
:08:
09
06/0
2/0
8 19
:37:
19
06/0
5/0
8 08
:06:
29
06/0
7/0
8 20
:35:
39
06/1
0/0
8 09
:04:
49
06/1
2/0
8 21
:33:
59
06/1
5/0
8 10
:03:
09
06/1
7/0
8 22
:32:
19
06/2
0/0
8 11
:01:
29
06/2
2/0
8 23
:30:
39
06/2
5/0
8 11
:59:
49
06/2
8/0
8 00
:28:
59
06/3
0/0
8 12
:58:
09
07/0
3/0
8 01
:27:
19
07/0
5/0
8 13
:56:
29
07/0
8/0
8 02
:25:
39
07/1
0/0
8 14
:54:
49
07/1
3/0
8 03
:23:
59
07/1
5/0
8 15
:53:
09
07/1
8/0
8 04
:22:
19
07/2
0/0
8 16
:51:
29
07/2
3/0
8 05
:20:
39
07/2
5/0
8 17
:49:
49
07/2
8/0
8 06
:18:
59
07/3
0/0
8 18
:48:
09
08/0
2/0
8 07
:17:
19
08/0
4/0
8 19
:46:
29
De
lta
T i
n D
eg
F
-1
-0.9
-0.8
-0.7
-0.6
-0.5
-0.4
-0.3
-0.2
-0.1
0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1
Dif
fere
nce
in
rea
din
gs
- D
egre
es F
MET TWR AVG A DELTA TEMP (245FT - 33FT)-META69 MET TWR AVG B DELTA TEMP (245FT - 33FT)-METB69
Stability Class delta T difference (meta69-metb69)
Negative value implies that the 245' level is cooler than the 33' level. This is normal.
Positive value implies that the 245' level is warmer than the 33' level. This is an inversion.
G
F
E
BC
D
A
Tolerance Band
24hrs – Sunny vs Cloudy
-4
-2
0
2
4
6
8
10
12
14
08/0
5/08
14:
45:3
8
08/0
5/08
15:
28:5
0
08/0
5/08
16:
12:0
2
08/0
5/08
16:
55:1
4
08/0
5/08
17:
38:2
6
08/0
5/08
18:
21:3
8
08/0
5/08
19:
04:5
0
08/0
5/08
19:
48:0
2
08/0
5/08
20:
31:1
4
08/0
5/08
21:
14:2
6
08/0
5/08
21:
57:3
8
08/0
5/08
22:
40:5
0
08/0
5/08
23:
24:0
2
08/0
6/08
00:
07:1
4
08/0
6/08
00:
50:2
6
08/0
6/08
01:
33:3
8
08/0
6/08
02:
16:5
0
08/0
6/08
03:
00:0
2
08/0
6/08
03:
43:1
4
08/0
6/08
04:
26:2
6
08/0
6/08
05:
09:3
8
08/0
6/08
05:
52:5
0
08/0
6/08
06:
36:0
2
08/0
6/08
07:
19:1
4
08/0
6/08
08:
02:2
6
08/0
6/08
08:
45:3
8
08/0
6/08
09:
28:5
0
08/0
6/08
10:
12:0
2
08/0
6/08
10:
55:1
4
08/0
6/08
11:
38:2
6
08/0
6/08
12:
21:3
8
08/0
6/08
13:
04:5
0
08/0
6/08
13:
48:0
2
08/0
6/08
14:
31:1
4
Del
ta T
in D
eg F
0
2
4
6
8
10
12
14
Win
d S
pee
d (
mp
h)
B Delta T A Delta T Stability Class AB C D EF A Wind Speed B Wind Speed
Negative value implies that the 245' level is cooler than the 33' level. This is
Positive value implies that the 245' level is warmer than the 33' level. This is an inversion.
G
F
E
BC
D
A
G-Extremely StableD-NeutralA-Extremely Unstable
Self Assessment Initiation
• History of problems with met tower data– NRC Submittal – 0% Recovery in 2001 – Prep for Submittal – 0% Recovery in 2005– Answers to questions to peers LTA– List of issues growing
• Initiated Self Assessment– Team Makeup– In Depth Look – 29 checklist questions
Organizations Affected• Reactor Engineering (responsible for accident analysis using met tower
data)• Licensing (met tower regulatory commitments and LBD management)• EP (Interested party for real time met data and offsite dose software
applications)• Environmental Services (Responsible for environmental monitoring based
on met tower data and data trending)• Chemistry (Responsible for a) effluent monitor setpoint calculations and b)
routine and abnormal release dose calculations both based on real time and historic met tower data)
• System Engineering (Responsible for instrument performance)• Work Planning and scheduling (Responsible for repair of met tower
instruments)• IT (Responsible for met tower data software and computer hardware
support)• I&C (Responsible for Surveillances (calibrations))• Maintenance (Responsible for preventive & corrective maintenance)
Checklist Questions• Desert Sigmas• Heat Emission Rates• Reference Bases • Data Recovery• Annual Rainfall• Diffusivity• Rain Collection• Signal Trending• Data Screening• Wind Frequency Rejection• Instrument Separation• Sigma Theta• Guy Wires• As Found Calibration Distribution
• Diffusivity• Instrument Cables• Solar Instrument• Interference Zones• Dew Point• Solar Shields• Training• Data Trending• Remediation Tent Interference• ISFSI Heat Effect• Terrain Effects• Advantages of ANSI 3.11-2005• Corrective Action Effectiveness• Met Tower Walkdown
Self Assessment Findings
• Accuracy Commitment• TS/LCS/ODCM/FSAR• Calibrations Methodology• Trending • Training• Tower Design/Climbing• Work Request Priority• LTA Consensus of Problems
Self Assessment Findings
Accuracy Commitment• Where conflicts exists between
recommendations of – RG 1.97 Rev 2 and – Safety (Regulatory) Guide 1.23 Rev 0-1972,
• CGS complies with RG 1.97 • 0.2° vs 0.1°C for Delta T• Temperature sensor improvement
– Current sensor accuracy = ±0.30°C– Young sensor accuracy = ±0.10°C– MetOne sensor Accuracy = ±0.05°C
Accuracy Comparisons
CGS FSAR Accuracy Commitment
NRC Reg Guide 1.23 dated 2007
Delta T ± 0.2°C (± 0.36°F) ± 0.1 °C (± 0.18 °F)
Temperature
Wind Speed
Wind Direction± 5° starting threshold <
1 mph
± 0.5 °C (± 0.9 °F)
± 0.45 mph or 5% of observed wind speed starting threshold < 1 mph
± 0.50 mph from 0.5 to 5 mph, ± 10% of reading above 5 mph per RG 1.97, Rev. 3.
± 0.5°C (± 0.9°F)
± 5.0°
Threshold for ConcernVariance between
redundant sensors
Variance Threshold for Concern CGS FSAR
Temperature 33' 0.1
245' 66.9
Delta T13.9
±0.3°F Summer midday ± 0.4°F - Other Seasons
± 0.2°C (± 0.36°F)
WS<5mph WS>5mph
Wind Speed 33' -0.1 -6.3%
245'0.8 -7.9%
Wind Direction 33' 2.0
245' 0.5
± 0.2°F - Summer ± 1.0°F - Other
Seasons
± 1.0 mph from 0.5 to 5 mph, ± 20% of reading above 5 mph
± 10°
± 0.50 mph from 0.5 to 5 mph, ±10% of reading above 5 mph per RG 1.97, Rev. 3.
± 0.5°C (± 0.9°F)
± 5.0°
Self Assessment Findings
TS/LCS/ODCM/FSAR
• No LCO or RFO in TS, LCS, or ODCM for inoperable/non-functional met tower instruments
• FSAR describes program/surveillances
• Channel Checks not performed for one channel
Self Assessment Findings
Calibration Methodology• Sections of loop not included in calibration
– Lack of Cal Lab sensor data with loop test documentation
– Lack of line integrity test of tower cables– Lack of validation of computer signal
• Lack of aspirator inspection• As Found OOT not trended• Process slow or interrupted• Calibration by WO instructions
Self Assessment Findings
Trending• Frequency of instrument trends LTA • Depth of trending LTA
– Current procedure LTA for untrained personnel and LTA to identify problems and ensure timely corrective action
– Lack sufficient action threshold criteria and cross-organization approval of criteria chosen
– Does not trend all met tower signals & correct all channels, not just FSAR channels.
– Does not compare signals to nearby towers– Limited methods– Interference zones not identified
Self Assessment Findings
Training
• Turnover of personnel
• Background of personnel
• Time/schedule for training
• Funding
• Many groups need training– Right-hand not knowing Left-hand needs
Self Assessment Findings
Work Request Priority
• With no LCO or RFO, work priority has been low
• System Engineers with nuclear safety-related systems & met tower instruments must balance limited resources
Self Assessment Findings
LTA Consensus of Problems
• Engineering personnel are not trained in meteorology
• Belief that a system is not OOT until proven by calibration
Self Assessment Findings
Tower Design• Temperature probes on opposite sides of tower• Wind vane design generating wind shadow• Annual Rainfall runs November to November• Torque guy system wires makes instrument
elevator design difficult– Hesitancy to increase frequency of calibrations
• Tower Climbing– Windy, icy conditions– Maintenance delays (6 – 7 months)
Self Assessment Findings
Others• Input parameters in XOQDOQ
– Heat Emission Rate– Terrain Height– Exit Direction
• XOQDOQ– Desert Sigma
• Data Validation LTA• JFD creation software not robust enough to
defend low work prioritization
Self Assessment Results
• 13 Condition Reports – Includes Licensing Bases Documents and
implementing procedure revisions to ensure compliance with commitments.
• 18 Action Request Evaluations to – Consider design changes to improve accuracy and
reduce bias of met tower signals, to – Consider software changes to process and validate
met tower data prior to use in LBD submittals or ODCM compliance assessments, to
– Ensure knowledge retention, and to – Validate input values to dose assessment calculations
End Presentation
• Discussion questions:– How do you convince Engineering or
Maintenance that repair is needed?– How is tower maintenance performed in icy,
windy conditions without an elevator? – Can delta T accuracy requirements of RG
1.23 Rev 1 be met? – Others?