ML20205N827

Technical Evaluation Rept of 1984 Meteorological Data from Rancho Seco Nuclear Power Plant

ML20205N827
Person / Time
Site:	Rancho Seco
Issue date:	01/31/1986
From:	Andrews G Battelle Memorial Institute, PACIFIC NORTHWEST NATION
To:	NRC
Shared Package
ML20205N830	List: IR 05000312/1985035 ML20205N827
References
CON-FIN-B-2536 NUDOCS 8605080425
Download: ML20205N827 (23)

Text

_ . .

Enclosure 2

, January 1986 I

Technical Evaluation Report of 1984 Meteorological Data from the Rancho Seco Nuclear Power Plant Submitted by: Gregg L. Andrews Battelle Pacific Northwest Laboratories P.O. Box 999 Richland, WA 99352

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Table of Contents 1.0 Introduction 2.0 Data and Measuring Site Description 3.0 Limitations of Comparative Analysis 4.0 Data Evaluation 4.1 General Discussion 4.2 Evaluations 4.2.1 Data Recovery 4.2.2 Delta-Temperature 4.2.3 10 meter Wind Direction and Speed 4.2.4 60 meter Wind Direction and Speed 4.2.5 Inconsistencies between the 10 meter and 60 meter Winds 4.2.6 Temperature at 10 meters 4.2.7 Dew Point at 10 meters 5.0 Conclusion References Appendix A -

Sacramento Municipal Utility District Data Format l

l

1.0 Introduction i Meteorological data at operating reactor sites must be available for use in emergency response situations as well as to demonstrate that routine releases of radioactive material to the atmosphere result in doses below the guidelines of 10 CFR 50 Appendix I. As discussed in Information Notice No. 84-91 issued by the Office of Inspection and Enforcement, the quality of meteorological data collected at operating reactor sites is important to ensure appropriate

integration into emergency response actions and to ensure appropriate

, assessments of the radiological impacts of routine releases.

This report describes and evaluates the quality, data reliability, and

{ representativeness of the 1984 Rancho Seco meteorological data for use in i emergency response and assessments of the radiological impact of routine l releases.

The evaluation was performed by processing the 1984 data with existing NRC quality assurance computer codes (Snell 1982) and by processing concurrent meteorological data from the National Weather Service (NWS) station at Sacramento with computer codes specifically developed for this evaluation. A

, NWS station was a logical choice because, in most cases, the weather data were complete and the reliability and quality of the data were assured.

Additionally, historical and concurrent annual and monthly local climatological data (NOAA 1980 through 1984) were also obtained from the Sacramento NWS i station. Previous site data was taken from the Rancho Seco Final Safety Analysis Report (Rancho Seco 1971). Much of the data are presented in graphical

! form to facilitate the comparisons between different sets of data for the same variable.

The 1984 Sacramento meteorological data (e.g., wind speed, temperature, etc.) were compared to the long term (30 years in some cases) climatological means and extremes for Sacramento to determine if 1984 was an anomalous year.

4 The 1984 data were found to lie within the climatological extremes and did not show any anomalous tendencies.

l The variables analyzed were wind speed, wind direction, stability, temperature, 4

and dew point. Emphasis is placed on wind speed, wind direction, and stability because of their integration into emergency response actions and assessment of the radiological impacts of routine releases. Analyses of temperature and dew point provide further evaluation of the climatological representa-

tiveness.

The NRC quality assurance programs were developed to assess the quality and reliability of a licensee's meteorological data. These codes consist of the following programs: DATE, MISS, JFREQ, STABQ, and QA. DATE locates adjacent i records that are not sequential in date or time, MISS tabulates the number of missing occurrences for each parameter at three different levels, JFREQ creates joint frequency distributions of wind speed, wind direction and stability, STABQ tabulates the stability classes by continuous periods of occurrence for 1 up to three different levels using the delta-temperature method or sigma theta i method, and QA flags questionable occurrences of wind speed, wind direction, temperature, dew point, delta-temperature and precipitation.

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Codes specifically developed for the evaluation were TEMP _DEWPT, DELTA _T_CHK and SFC1440. The TEMP DEWPT program tabulates the monthly averages, extreme minimum and extreme maximum temperature and dew point from the data submitted by the utility. DELTA _T CHK compares the values of the delta-temperature sensor and the differenc_e between the temperatures at the corresponding levels.

The SFC1440 program produces a joint frequency distribution of wind speed and direction, categorizes wind speed occurrences and summarizes monthly averages and extreme minimum and extreme maximum temperatures from data at the nearby NWS station.

2.0 Data and Measuring Site Description i

The Sacramento Municipal Utility District (SMUD) submitted a magnetic tape containing hourly meteorological data from January 1984 through December 1984.

The data were recorded at 10 meters and 60 meters on a single tower located on site. The table below indicates what variables were recorded at each level.

60 meter 10 meter Delta-Temperature Temperature Temperature .

60 meters - 10 meters i 60 minute Sigma Theta Dew Point

Wind Speed 30 minute Sigma Theta ,

Wind Direction 10 minute Sigma Theta '

3 minute Sigma Theta Wind Speed Wind Direction Precipitation was not included with the data.

The data were not in the format as described in section 2.3.3 of the Standard Review Plan (NRC 1981). However, the data were accompanied with documentation indicating the format used by SMUD (Appendix A). The SMUD format provided two channels of data, the primary channel was A and the secondary channel was B. The variables delta-temperature (60 meters - 10 meters), dew point and wind speed and direction at 10 meters were recorded on both channels. In these cases, data from channel A were used unless the data were missing in which case data from channel B were used.

The site is located in the lower end of the Sacramento Valley between the

. Sierra Nevada mountain range to the east and the Coast Range along the Pacific Ocean to the West. The region is flat to slightly rolling hills with a site elevation of 61 meters (MSL) at Sacramento. East of the site, the land becomes more rolling, rising to an elevation of 185 meters (MSL) at 10 kilometers and increasing in elevation thereafter approaching the Sierra Nevada mountain range. Elevations of over 3000 meters occur 100 kilometers east of the site.

Onsite meteorological measurements are made on a 60.9 meter (200 ft) tower located approximately 915 meters (3000 ft) east from the reactor building and cooling towers. The immediate area surrounding the tower is unobstructed by

trees, buildings, and major topographical features.

i 2

t 3.0 Limitations of Comparative Analysis

, The 1984 Rancho Seco meteorological data were evaluated by a comparison with i

previous site data and concurrent and historical meteorological data from j Sacramento. This kind of comparative analysis provides insight into the climatological representativeness of the Rancho Seco data. However, it is

recognized that different regional meteorological characteristics exist in the Central Valley region (e.g., divergence zone, discussed in section 4.0).

In situations were a variable shows marginal discrepancies in the comparative analysis, it would be difficult to determine if the problem is the result of instrument malfunction, a response to regional meteorological characteristics or a local exposure concern caused by small-scale influences such as buildings and local terrain.

4.0 Data Evaluation Data reliability and quality of the 1984 Rancho Seco data set were assessed using the NRC quality assurance codes. Climatological representativeness was evaluated through comparisons with previous site data and data from the Sacramento NWS station.

Two NWS stations are located near the Rancho Seco facility: Sacramento and Stockton. Observations used by the Sacramento NWS station are reported from the Sacramento Executive Airport which is twenty-three miles northwest of Rancho Seco. The Stockton NWS station is: located thirty miles to the south-southwest of the plant.

The Central Valley area in which Sacramento, Stockton and Rancho Seco are located is meteorologically unique. A well-documented surface divergence zone (Fig.1) 13 dominant in the Central Valley region during the late spring, -

summer and early fall (Energy Resources 1981). Cool, moist low level air flows through the Golden Gate and Carquinez Straits toward the Central Valley.

Inland terrain directs this air flow into the Central Valley, where it diverges due to the " blocking" affect from the Sierra Nevada mountain range. Apparently, Rancho Seco is located within the divergence area, while Sacramento is within the northerly moving air and Stockton within the southerly moving air. Thus, -

it would appear neither Sacramento nor Stockton would be climatologically representative for wind data applied at Rancho Seco. However, adjustments can be made by considering this influence when analyzing the wind data.

The Sacramento NWS station was chosen for the comparison begause of its closer proximity and more complete weather information. The Stockton NWS station discontinued twenty-four service and observations in September 1981. Currently observations are taken fourteen hours per day. The frequency of observations

does not provide adequate coverage to compare monthly and extreme values with the 1984 Rancho Seco data.  ;

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• 4.1 General Discussion The 1984 Rancho Seco meteorological data consists of variables recorded at 10 meters and 60 meters. Evaluations were performed on the data recovery, delta-temperature,10 meter wind speed and direction, 60 meter wind speed and direction,10 meter temperature and 10 meter dew point temperature.

Data recovery for the 10 meter wind speed and direction was high (97.5% and 94.7%, respectively), and the data appear climatological representative.

Variables that indicated some peculiarities were the. delta-temperature, 60 meter wind speed and direction, the dew point, and temperature. Other unusual aspects included low data recovery for all variables except 10 meter wind data and delta-temperature data and some apparently spurious high wind speeds at 10 meters and 60 meters.

4.2 Evaluations The following subsections contain discussions regarding the reliability, quality, and climatological representativeness of the 1984 Rancho Seco meteorological data. Also, concerns regarding data quality and/or pecularities which could impact SMUD's ability to resond to emergency situations or make routine dose calculations are discussed in this section.

4.2.1 Data Recovery The MISS program evaluates the reliability of meteorological data by calculating the percentage of data recovery. Even with a redundant system for some variables, the 1984 Rancho Seco data set contained data recoveries below 90%

for all of the variables at 60 meters and the temperature and dew point at 10 meters. Table 1 shows the percent of data recovery for all variables.

Table 1 Data Recovery i (Percent)  ;

60 Meter 10 Meter  :

Parameter Level Level Wind Speed 79.1 97.5 Wind Direction 88.2 94.7 Temperature 86.6 86.6 Dew Point Not Available 86.6 Delta-Temperature (60m-10m) 95.3 l

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Regulatory Safety Guide 1.23 (NRC 1972) states that meteorological instruments should be inspected and serviced at a frequency which will assure at least 90% data recovery. The lower-than-expected data recoveries could be suggestive of problems in the instrument maintenance program at Rancho Seco.

In addition to poor data recovery, the DATE program indicated that out of a possible 8784 hours0.102 days <br />2.44 hours <br />0.0145 weeks <br />0.00334 months <br /> for the year 1984 only 8680 hours0.1 days <br />2.411 hours <br />0.0144 weeks <br />0.0033 months <br /> were recorded on tape; a total of 104 hours0.0012 days <br />0.0289 hours <br />1.719577e-4 weeks <br />3.9572e-5 months <br /> (1.2%) of data (all variables ) were completely missing.

If an emergency situation arose during these hours response actions could not 4

be performed without using offsite data, which is of limited usefulness because of the air flow divergence as discussed in Section 4.0. .

i 4.2.2 Delta-Tenperature The 1984 Rancho Seco delta-temperature values were compared with previous  ;

delta-temperature collected at the site data (1975) (NRC 1985) and historical (NCDC 1973) Pasquill-Gifford data (1966-70) from Sacramento (Fig. 2). The Pasquill-Gifford method uses cloud cover and wind speed to determine one of seven stability classifications while 'the delta-temperature uses vertical-temperature gradients to determine one of seven stability classes. .

These two methods are somewhat related because wind speed and cloud cover play -

! principle roles in the formation of vertical-temperature gradients. Data are presented in percent of occurrence versus atmospheric stability class. >

The 1984 Rancho Seco delta-temperature shows an unusually pronounced bias toward the neutral and slightly stable categories (D and E, respectively), with  !

approximately 86% of the stability occurrences in those categories.  !

Additionally, the QA program showed that the 1984 data contained a large number of neutral and slightly stable conditions during daylight hours for the months ,

in late spring, summer, and early fall (referred to as the warm months hereafter) . A closer examination of hourly data revealed the daylight hours contained only neutral and slightly stable conditions day after day throughout the warm months. The 1984 Rancho Seco delta-temperature distribution appears abnormal when compared with previous site and Sacramento data (Fig.2).

Meteorological considerations suggest that a higher frequency of unstable occurrences should exist during the daylight hours of the warm months. For example,1984 and historical local climatology from Sacramento and Stockton indicate the warm months generally contain a large number of days with clear skies and warm temperatures during daylight and cool temperatures at night.

Considering these conditions, a diurnal fluctuation in the local lapse rate

, is expected. The lower layers (~200 meters) of the atmosphere would experience diabatic cooling due to outgoing infrared radiation emitted from the ground during nocturnal hours. An inversion (i.e. temperature increasing with height) would result thus forming a stable layer of air. In contrast, the atmosphere during daylight hours would experience warming due to incoming insolation.

Thermal mixing would erode the nocturnal radiation inversion, reversing the temperature lapse rate, and resulting in unstable conditions. Furthermore, stations in basin and valley regions with low-level vegetation usually experience intense heating near the surface (~20 meters) creating super-adiabatic conditions. Super-adiabatic conditions exist when the 5

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From examination of onsite delta-temperature distributions and consideration of basic meteorological principles, the high frequency of stable conditions does not appear meteorologically dependent, and could reflect a malfunction or neglect within the delta-temperature measurement system.

4.2.3 10 meter Wind Speed and Direction A comparison between wind speeds from the 1984 Rancho Seco data set at 10 meters, 1975 Rancho Seco data at 10 meters, 1969-1970 Rancho Seco data at 15.2 meters, and 1984 Sacramento data at 6.1 meters is shown in Figure 3.

The comparison shows a reasonably close relationship among the different data sets which indicates the 1984 Rancho Seco 10 meter wind speeds are probably climatologically representative. Additionally, data reliability was good as reflected by its high data recovery (97.5%).

A comparison between wind directions from the same data sets as compared in the wind speeds is shown in Figure 4. The high percentage of calms at Sacramento is due to a high starting speed of 1.0 m/s. The wind direction at Rancho Seco has a more easterly influence than Sacramento. A likely explanation for the more easterly flow at Rancho Seco is its closer location to the Sierra Nevada mountain range relative to Sacramento. The foothills of the Sierras

, lie approximately 10 kilometers east of the plant with the mountain range rising to 3000 meters within 100 kilometers of the plant. Diurnal drainage flow from higher elevations would tend to give nocturnal winds a more easterly influence because of the terrain orientation. Other noticeable features are a strong southerly influence at Sacramento and a strong westerly influence at Rancho Seco. As explained in section 4.0 of this report, a well-documented surface divergence zone exists during the warm months (Fig. 1). Rancho Seco appears to lie within the divergence zone, thus receiving a more westerly ,

influence. Sacramento however, lies within the air moving northward thus  :

receiving a more southerly influence.

An intercomparison of wind directions at Rancho Seco from previous data sets shows a close relationship.

On a regional scale, the 1984 Rancho Seco wind directions appear climatologically representative because of the close relationship to previous onsite wind direction distributions and wind direction distributions associated with Sacramento. Additionally, data reliability was good because of its high data recovery (94.7%).

The analysis shows that the 10 meter wind data would probably be reliable and representative during emergency response situations and routine dose calculations. However, there remains an inability to detect local exposure Toncerns because of small-scale influences such as butidings and local terrain.

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4.2.4 60 meter Wind Speed and Direction The 1984 Rancho Seco 60 meter wind speed was compared with the corresponding 10 meter wind speed (Fig. 5). The percentages for the speed categories 2.0 -

l 3.0 m/s and 3.0 - 5.0 m/s at 10 meters appeared high compared to the 60 meter

level, the QA program provided some insight into this peculiarity. The program showed the 60 meter wind speed was less than the 10 meter wind speed for 1686 ,

occurrences, 24.5%, based on the total number of valid hours for 60 meter wind speeds. This seems to be a rather large number of occurrences because frictional affects tend to decrease wind speeds at lower levels under most weather conditions which would yield a wind profile of wind speeds increasing with height. However, these occurrences were further analyzed by inspecting  ;

them as a function of time of day and season. The inspection indicated a  !

diurnal and seasonal relationship with the occurrences appearing mostly in i the afternoon during the spring and summer. Those occurrences could be caused by a malfunction within the 60 meter wind speed system or by the local l

meteorology, possibly the surface divergence zone associated with the Central Valley during the warm months. Based on this conclusion it cannot be detennined whether or not the 60 meter wind speed is actually climatological 1y representative. Further comparative analysis with multiple levels of wind data from towers on and off the site is needed to determine if the data is climatologically representative. l Even if the 60 meter wind speed were climatologically representative, it is not reliable because of its low data recovery (79.1%). The availaSility and reliability of the data could be questionable in emergency response situations.

The 1984 Rancho Seco 60 meter wind direction was compared with the corresponding 10 meter wind direction (Fig. 6). Large discrepancies were noted in some of ,

the sectors (N, SE and WNW). The QA program provided some insight into this l peculiarity; a number of occurrences (7.0%) were noted where the wind direction difference between 60 meters and 10 meters was greater than or equal to 22.5 degrees (one sector) while the wind speed was greater than or equal to 5.0 m/s. 1 Although surface frictional affects tend to turn lower level winds counterclockwise, the deviation under moderate wind speeds (e.g. 5.0 m/s) l should be no more than ten to fifteen degrees for a 200 meter wind profile in a low-level vegetation environment with relatively flat terrain. A close inspection of these occurrences showed the 60 meter wind direction was inconsistent with the 10 meter wind direction. It appears r?arious values are allowed to enter the 60 meter wind direction measurement system. Assuming the 10 meter wind direction is representative, the 60 meter wind direction does not appear to be climatologically representative and is internally inconsistent with the 10 meter wind direction data. Additionally, the 60 i meter wind direction is unreliable due to its low data recovery (88.2%).

All of this could have detrimental affects on routine dose calculations and l

emergency response situations for elevated releases.

4.2.5 Inconsistencies between 10 meter and 60 meter Winds The QA program revealed the maximum hourly wind speed for the 10 meter level was 42.4 m/s, while 55.1 m/s was recorded for the 60 meter level. Such speeds i 7 l

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! observations were made on different dates (March 26 and October 5, i respectively). Additionally, when the 60 meter level recorded 55.1 m/s for an hourly average the 10 meter level recorded 2.2 m/s for the same hour.

Unfortunately, the 60 meter hourly wind speed was missing when the 10 meter wind speed recorded 42.4 m/s. The 1984 fastest mile from Sacramento was used to compare against the maximum hourly wind speeds at the 10 meter and 60 meter levels. The fastest mile is essentially an instantaneous (approx. 5-10 second average) value, and should always exceed the hourly average for the same hour.

The fastest mile wind speed recorded at Sacramento in 1984 was only 17.0 m/s at the 6.1 meter level. Although small-scale meteorological phenomena (e.g.,

downbursts and microbursts) can cause sharp regional variations, the excessive wind speeds at Rancho Seco are not likely related to downbursts or microbursts because thunderstorms (the must probable causative mechanism) were not observed

at Sacramento on those days and downbursts and microbursts are shortlived phenomena (10 to 15 minutes).

l The observations occurrence of 42.4 of excessive m/s There winds. and 55.1 werem/s windoccurrences several speeds were not the only(e.g.,

of high greater than 25.0 m/s) hourly wind speeds in Octcber which appear to be spurious values when compared to climatological wind information from Sacramento before j the wind speed system was apparently corrected.

The above discussion and the internal comparative analysis for the 60 meter wind direction discussed in Section 4.2.4 showed some internal inconsistencies between the 10 meter and 60 meter level wind data. These kinds of

. inconsistencies indicate an apparently poor maintenance and quality assurance program which allows spurious values to enter into the wind data, i

4.2.6 Temperature at 10 Meters Monthly temperature average, extreme monthly maximum temperatures, and extreme monthly minimum temperatures for 1984 were compared with 1984 temperature data from Sacramento (Fig. 7). Although the monthly averages show a close relationship, some of the Rancho Seco extreme values are beyond the climatological limits of Sacramento, especially extreme monthly minimums in April, July, and November and the extreme monthly maximum in December. A

further comparison using historical data (i.e. 30 year normal for averages

and 34 year range of extreme values) from Sacramento questions several of the extreme values (Fig. 8). In particular, April and July extreme minimum values are well outside the climatological range, which would either indicate a very unusual meteorological pattern in 1984 or problems with the measurement system.

The 1984 Rancho Seco temperatures at 10 meters appear to be in reasonable agreement with climatological records from Sacramento. However, once again, as with other variables, some problems are apparent with the measuring system which have resulted in spurious values.

i 8 l

1 -- -. --- - - -- -- .-. - -

4 4

TEMPERATURE COMPAR1 SON 1984 50 4s- o RS MAX t

j +0-  ! h , f x RS AVE o  ! I

< ss- i  !

C

, RS MIN I

i 3o. ,

, SAC MAX

i e

. y a 23 , , I a SAC AVE Sw y I I n l c gb o 1 u 3

• l SAC MIN w e 20 - x , ; l se i- i  ! ,  ; a.

sw o I  ; .

Wo is- ,

~

• I I I. ,

a i

! r l

• i tot  ! A i i  :

i 2 I i 1

• 4  :

I A s-- l 1 l, l

! 4 1 4 0 1 i

• J F M A M J J A S O N D MONTH .

I r ,,

Figure 7 1

_ . ~ . . - - - . , - _ - - . _ . . - _ - - __-!

TEMPERATURE COMPARISON 1984 RANCHO SECO VS SACRAMENTO HISTORICAL so 43-- a RS MAX 4o- " x RS AVE 8'

3,. a RS MIN i

l so-- l SAC MAX si

,, l w u l  ;

-- SAC AVE

@***' n l n '

SAC MIN 2o- n "

.'[

$w w o ,,. "

n n u ' .

'o- 's "

f l n a ,  ;

m o

a- I a .,

• ~

4 4 o  !

4  !

J F M A M J J A S O N D MONTH Figu e 8

\

i l

4.2.7 Dew Point at 10 meters The 1984 dew point temperatures at Rancho Seco were significantly lower than concurrent dew point values at Sacramento (Fig. 9). Dew point temperature is a measured value at both Rancho Seco and Sacramento. In some months, the dew point average at Rancho Seco differed by more than 12,C from the Sacramento I measurement. Additonally, an intercomparison of monthly averages and extreme 1 values indicate some disturbing results. For example, monthly averages and I extreme maxima for the months of January through May are higher the summer months, which appears contrary to meteorological principles. The dew point should reach a maximum during the summer and minimum.during the winter, as the Sacramento monthly distribution clearly indicates. The 1984 Rancho Seco values appear totally unreliable and cannot be climatologically representative.

The data appear to wander aimlessly, which may be indicative of poor quality assurance for the measurement system.

5.0 Conclusion From examinations of data collected at Rancho Seco in 1984, the quality assurance and maintenance program for the meteorological measurement system appears generally ineffective. This conclusion is based on the number of spurious values that are allowed to pass into the recording system and the lower-than-expected data recovery for all variables except the 10 meter wind data and delta-temperature.

A principal concern with the meteorological data acquisition and collection program is the measurement of delta-temperature, used as an indicator of atmospheric stability. The apparent bias in the stability distribution to neutral and slightly stable conditions is must likely due to instrument malfunction rather than meteorological considerations. Without a reliable indicator of atmospheric stability, dose calculations are suspect.

Emergency response capabilities would not only be affected by the erroneous delta-temperature values, but also by low data recovery. Spurious valu .

such as those found throughout the data acquisition system, and internai inconsistencies in wind speed and direction observations at the 10 meter and 60 meter levels, could significantly affect emergency response calculations and recommendations for protective action.

9 I

b 1

b DEWPOINT COMPARISON a

a 35- a RS MAX se- x RS AVE a ,

I + RS MIN 2o- SAC MAX

-- SAC AVE

. . o '8' f z " --

5 o si SAC MIN

.0- n gh is

.. ii Q"

s- 1r ai o n .

a u JE IE

. m ,,

_3

, + ,

-in- . g

~ .

=20 J F M A M J J A 5 O N C MONTH Figure 9 I

i

. , - -_ . - - - . . , - , . ,. _ _ . - _ , , , _ - - - - _ _ _ . - - .._..,-.,_r., - , - .. . _ , _ - - . . - . . , - - .

REFERENCES l l

Energy Resources Co., Inc. 1981. Meteorological Review for the Rancho Seco Emergency Preparedness Program. Prepared for the Sacramento Municipal Utility District, Sacramento, California.

NCDC. 1973. Seasonal and Annual Wind Distribution by Pasquill Stability Classes (6) Star Program, Station 23232, Sacramento, California. National Climatic Data Center, Asheville, North Carolina.

NOAA. 1980-1984. Local Climatological Data, Annual Summaries. National Oceanic and Atmospheric Administration, Asheville, North Carolina.

NRC. 1972. Onsite Meteorological Programs. Regulatory Guide 1.23 (Safety Guide 23), (February 17,1972), U.S. Nuclear Regulatory Commission, Washington, D.C.

NRC. 1981. Standard Review Plan. NUREG-0800, U.S. Nuclear Regulatory Commission, Washington, D.C.

NRC. 1985. Data provided by the NRC in the form of personal communication.

Rancho Seco. 1971. Preliminary Safety Analysis Report, Amendment 5 (For the Rancho Seco Nuclear Generating Station, Unit 1). Docket-50312-23, Sacramento

! Municipal Utility District, Sacramento, California.

Snell, William. 1982. Nuclear Regulatory Commission Staff Computer Programs for use with Meteorological Data. NUREG-0917 U.S. Nuclear Regulatory Commission, Washington, D.C.

10

e Appendix A I

1 l

l 1

i I

METEOROLOGICAL DATA ,

A YtANUAYHK4k AUI A U I' ail 0 AW5iO AWU10 Acu30 Ace 10 Ace 3 AW56G X/Q 6 YEARDAYHR 1L 80T AT60 BOP BWS10 BWD10 Bo030 Boe10 Bo03 AWO60 Ao060 YEAR ie 1985 DAY day of the year HR hour of the day ADT delta temperature, "F, (60 ~ meter - 10 meter) A channel

.s BOT delta temperature,, *F, (60 meter - 10 meter) B channel ADP dew point, 'f, 10 meter, A channel BOP dew point. *f, 10 meter, B channel AT10 temperature. *F,10 meter, A channel AT60 temperature, *T, 60 meter, A channel AWS10 wind speed, mph, 10 meter, A channel AWD10 wind direction,

• f rom, Ib meter, A channel (N-0*, E-90*)

BWS10 wind speed, mph, 10 meter, B channel BWD10 wind direction

• f rom,10 meter, B channel (N-0*, E-90*)

ce standard deviation of wind direction 30 - 30 minute o, 10 meters 10 - 10 minute o, 10 meters 3- 3 minute o, 10 meters 60 - 60 minute o, 60 meters ,

AWS60 wind speed, mph, 60 meter, A channel AWD60 wind direction,

• from, 60 meter, A channel X/0 E-06 sec/m2 at 700 meters distance

%g