ML17212A865

Reg Guide 1.145 Updated Accident Analysis.

ML17212A865
Person / Time
Site:	Saint Lucie
Issue date:	09/23/1981
From:	Krivo S, Spickler I DAMES & MOORE
To:
Shared Package
ML17212A864	List: ML17212A862 ML17212A865
References
RTR-REGGD-01.145, RTR-REGGD-1.145 4598-131-09, 4598-131-9, NUDOCS 8110070323
Download: ML17212A865 (30)

Text

REPORT REGULATORY GUIDE 1.145 UPDATED ACCIDENT ANALYSIS ST. LUCIE, FLORIDA For FLORIDA POWER 81 LIGHT COMPANY 23 September 1981 4598-131-09

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8110070323 810939 PDR ADQCK 05000289 A y PDR

Dame&. Moore 455 East Paces Ferry R Atlanta, Georgia 30363 uite 200 (404) 262-2935 TWX: 810-751-8218 Cable address: DAMEMORE 23 September 19B1 Florida Power 5 Light Company Suite 113 2250 Palm Beach Lakes Blvd.

Rest Palm Beach, Florida 33409 Attention: Mr. Robert G. Fisher Gentlemen:

Re: Regulatory Guide 1.145 Updated Accident Analysis St. Lucie Site The enclosed report is an updated accident analysis for the St. Lucie Unit 2. This update analysis includes two modifications that are different from the methodology presented in the Final Safety Analysis Report (FSAR) for this facility:

Reduced meander consideration to compensate for the anticipated effect of the coastal exposure of this site; Regulatory Guide 1.145 methodology for the evaluation of the accident periods of interest.

This updated accident analysis was initiated in response to a Nuclear Regulatory Commission's request. Comparison of these results with the those presented in the St. Lucie Unit 2 Final Safety Analysis report reveals the updated Maximum Sector x/g values larger than those reported in the .-FSAR. Although two modifications have been made to the methodology for computation, an increase was expected because of the reduced meander consideration.

Please let us know if you have any questions or need further explanation.

Sincerely, DAMES 5 MOORE Irwin Spickler Partner Stanley J, Krivo, CCM Senior Meteorologist IS;SJK/pdg Enclosure

1.0 INTRODUCTION

The following accident relative concentration analysis has been performed in response to the Nuclear Regulatory Commission's request to consider a limited lateral spread of the plume due to the coastal exposure of the St. Lucie site. Specifically, observed stability classes G, F, E, and D were made one stability class more unstable for the determination of the lateral spread of the plume under meander conditions.

In addition to the change in the meander term, the method of anlaysis presented herein uses the updated analysis techniques docu-mented in Regulatory Guide 1.145. Both of these features of this updated accident analysis are different than that presented in the St.

Lucie Final Safety Analysis Report.

Dames-'R Moore

2..0 SHORT-TERM (ACCIDENT) DIFFUSION ESTIMATES The onsite meteorological data observed at the St. Lucie, Florida site for the period 1 September 1976 through 31 August 1978 were used to calculate the relative concentrations which could be anticipated in the event of an accidental release of radionucl ides into the atmos-phere. For the initial two hours after the release, these factors were calculated at both the actual exclusion area boundary (EAB) and low population zone (LPZ); for longer time periods, these factors were calculated at the outer boundary of the LPZ only.

The short-term calculation of diffusion estimates were performed using the 10-meter level observations of wind speed and wind direction with stability derived from the 10-58 m differential temperature system. The plant parameters used in this calculation are as follows:

Cross-sectional Area: , 2726 m2 Shape Factor: 0.5 Exclusion Area Boundary (EAB): 0.97 miles Low Population Zone (LPZ): 1.00 miles Diffusion calculations for accidental or short-term releases of radionuclides were performed in accordance with the criteria provided in Regulatory Guide 1.145 with the exception of the meander term. To account for the expected reduction in lateral meander due to the coastal location of St. Lucie, the lateral spread of the plume with meander was determined using one stability class more unstable than that observed. Specifically, the following stabilities were assumed only when determining the meander term for lateral plume spread:

Observed Stabilit Stabilit Used for Meander G F F E E D D C 2-1 Dames 8 Moore

It was assumed that the releases emanate from a point source near the ground and the effluent plume spreads according to a Gaussiah dispersion model.

2-2 Dames 8 Moore

2.1 THE MODEL FOR ACCIDENT DIFFUSION ESTIMATES FOR THE FIRST TWO HOURS In estimating atmospheric dispersion for the first two hour's fol-lowing an accident, relative concentrations were calculated at the ef-fluent plume centerline assuming complete ground reflection at all receptors. For ground-level releases, defined as release points less than two and one-half times the height of adjacent solid structures, the hourly relative concentrations were calculated as follows:

For neutral (D),or stable (E, F, or G) atmospheric stability conditions with wind speeds less than six meters/second:

x/Q ufo(ma o z A/2) y x/Q (2)

(3oo) y z x/Q, (3) u~07fE 0 y z where:

x/Q = relative concentration (seconds/meter ).

Uyo = hourly average wind speed at 10 meters above ground (meters/second).

= horizontal dispersion coefficient of the plume (meters); a function of atmospheric stability and distance.

<z = vertical dispersion coefficient of the plume (meters);

a function of atmospheric stability and distance.

E = lateral plume spread with meander and building wake effects (meters); a function of atmospheric stability, wind speed, and distance. t For distances of '800 meters or less, 'Ey = Moy where M is determined from Figure 2.0-1; for distances greater than 800 meters,

'y = ("-') 'y(800 )

'yj ~

2-3 Dames 8 Moore

A = smallest vertical-plane cross-sectional area of the reactor building '2726 meters2).

The calculated relative concentrations, X/Qq and X/Qz, were compared and the higher value selected. This value was then compared to X/Q3 (plume meander) and the lower of these two selected as the appropriate relative concentration for the hour of concern.

'or unstable (A, B, or C) atmospheric stability and/or for wind speeds of six meters/second or more, plume meander is not con-sidered; the appropriate relative concentration is the higher of the X/Q values calculated by Equations 1 and 2.

The dispersion coefficients, 0y and 0z, depend upon values of vertical temperature gradients between the 10-meter and 58-meter levels (i.e., ~T) at the site. Meteorological input data required for the model are onsite measu'rements of wind speed and wind direction at 10 meters and ~T. An hourly observation is considered to be calm if the wind speed is less than the threshold of the wind instruments. For calm conditions a wind speed is assigned equal to the vane or anemo-meter starting speed, whichever is higher. A wind direction is assigned in proportion to the directional distribution of non-calm winds with speeds less than 1.5 meters per second. No substitution was made for missing or invalid data.

These'ourly rela'tive concentration values were calculated at the Actual Exclusion Area Boundary (EAB) and at the Low Population Zone (LPZ). The resultant values were distributed, both by wind direction and independent of wind direction, to obtain the Maximum Sector X/Q values, Sector X/Q values, and 5X Overall Site X/Q values.

The Maximum Sector X/Q is defined in Regulatory Guide 1.145 as the highest of the 0.5 percentile X/Q values calculated for each of the 16 meteorological sectors. The 16 Sector X/Q values were calculated by Dames 8 Moore

constructing cumu1ative frequency distributions in each sector and deter'mining'the X/g value in each secto'r that was exceeded 0.5 percent: .

of the total time. Calculations were made at both the EAB and LPZ.

For the LPZ, Sector X/g values were also determined for various time periods using logarithmic interpolation between the 2-hour Sector X/g and the annual average X/g in the same sector. For each time period, the highest of the 16 Sector X/9 values is the Maximum Sector X/Q for that time period.

The 2-hour X/g value that is exceeded 5 percent of the time is defined in Regulatory Guide 1. 145 as the 5X Overall Site X/g value.

The 5X Overall Site X/g value was deterined from the overall frequency distribution of hourly X/g values for all sectors combined. Calcula-tions were made at both the EAB and LPZ. For the LPZ, 5X Overall Site X/g values were determined for appropriate time periods using logar-ithmic interpolation between the 2-hour 5X Overall Site X/g at the LPZ and the maximum of the 16 annual average X/g values calculated at the LPZ.

2-5 Domes8 Voore

2.2 METHOD USED FOR ACCIDENT DIFFUSION ESTIMATES FOR PERIODS LONGER THAN TWO HOURS The method used to calculate the accident relative concentrations for time periods longer than two hours was a plotting technique described in Regulatory Guide 1.145. This technique is based on the calculated 0-2 hour X/Q values (Section 2.1) and the annual average estimates of x/(} as presented in the St. Lucie Unit 2 Final Safety Analysis Report (FSAR). These'iffusion estimates are performed only 1,

I at the Low Population Zone for time periods of 0-8 hours, 8-24 hours, 1-4 days, and 4-30 days as required by Regulatory Guide 1.70.

The procedure for determining these relative concentrations con-sists of a logarithmic plotting of the 0-2 hour x/g values for a given sector and the annual average x/9 for the same sector, both calculated at the LPZ distance. These two points (x/g at 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br />, x/g at 8760 hours0.101 days <br />2.433 hours <br />0.0145 weeks <br />0.00333 months <br />) are plotted on a log-log graph (with x/g as the ordinate and time in hours as the abscissa) and connected by a straight line. One straight line is generated for each wind direction sector. This log-

'log plot of relative concentrations is then read at 8, 16, 72, and 624 hours0.00722 days <br />0.173 hours <br />0.00103 weeks <br />2.37432e-4 months <br />. Sixteen Sector x/g values, one for each wind direction sector, were determined at 8, 16, 72, and 624 hours0.00722 days <br />0.173 hours <br />0.00103 weeks <br />2.37432e-4 months <br />, corresponding to values for time periods of 0-8 hours, 8-24 hours, 1-4 days, and 4-30 days.

From these four sets of 16 Sector x/g values, one set for each time period, the highest'f the 16 Sector X/g values for each time period was identified. These 'values are the Maximum Sector X/g values associated with the respective time periods.

It should be noted that the above procedure was used to determine Sector x/g values and Maximum Sector x/g values at the 0.5, 5, and 50 percentile levels. Although these percentile values should be deter-mined including all observations (zero average values included), only the 0.5 percentile level will yield Sector X/g values for each direc-tion that are non-zero using this total data base. To provide values that are non-zero for all directions, the 5 and 50 percentile Sector x/g values were determined using only those observation affecting the 2-6 Dames 8 h'oorc

given sector (zero values excluded). In each case, the 0-2 hour x/g value used was that associated with the appropriate percentile level.

In addition to the above, the 5X Overall Site x/(} values for the various time periods were determined through logarithmic interpolation between the 2-hour x/9 value that is exceeded 5 percent of the time, considering all wind directions, and the maximum of the 16 annual average X/g values.

2-7 Dames R fdoac."

2.3 ESTIMATES OF 0-2 HOUR ACCIDENT RELATIVE CONCENTRATIONS The concurrent hourly values of differential temperature, wind direction and wind speed were used to develop the frequency distribu-tions of hourly relative concentrations (used for periods up to two hours) using the methodology presented in Section 2.1. Table 2.0-1 presents sel'ected relative concentrations at the 5- and 50-percentile levels for the resultant cumulative frequency distribution of these hourly values of relative concentration for both the Exclusion Area Boundary (EAB) and the Low Population Zone (LPZ).

Considering the total, direction independent, cumulative frequency distribution for the EAB distance, the relative concentration that will be exceeded 5 percent of the time is 9.38E-5 sec/m . The value of 2.54E-5 sec/m will be exceeded 50 percent of the time for the EAB.

The LPZ values of relative concentration that will be exceeded 5 and 50 percent of the time are 9.04E-5 sec/m3 and 2.43E-5 sec/m , respec-t ively.

The 0.5 percentile directional dependent relative concentrations for the 0-2 hour accident period are presented in Table 2.0-2. These values are defined in Regulatory Guide 1.145 as the 16 Sector X/g values. Table 2.0-2 presents the Sector X/g values for both the EAB and LPZ distances. The Maximum Sector X/g values, the highest of the 0.5 percentile Sector X/g values, are 1.64E-4 for the EAB distance and 1.59E-4 for,'the LPZ.

2-8 Dames 8 Moore

2.4 ESTIMATES OF ACCIDENT RELATIVE CONCENTRATIONS FOR PERIODS LONGER

. THAN TWO HOURS Relative concentrations at the boundary of the low population zone (LPZ) were calculated for accident periods of 0-8 hours, 8-24 hours, 1-4 days, and 4-30 days for each wind direction sector. Section 2.2 presents the methodology used. The relative concentration values pre-sented are associated with the 0.5, 5, and 50 percentile levels. It should be noted that the 0.5 percentile values were determined from distributions including observations not in the sector of interest (zero averages included) while the 5 and 50 percentile values only con-sidered those observations that were in the sectors of interest (ex-cluding zero averages). Relative concentrations including zero averages were determined using the total number of observations for the data period, while the relative concentrations excluding zero averages were determined using only the number of observations affecting a given sector.

Tables 2.0-3, 2.0-4, and 2.0-5 present the results of the accident analyses for the various time periods. The interpretation of these tables is illustrated as follows: if an accident occurs, there is' 0.5 percent chance that the relative concentration averaged over the next 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> will exceed 3.0E-5 sec/m3 at the LPZ in the north sector. For Tables 2.0-4 and 2.0-5 the interpretation is illustrated as follows: if an accident occurs and the wind is affecting the NNE sector, there is a 5.0 percent chance the relative concentration for the 0-8 hour interval will exceed 4.07E-5 sec/m3 at the LPZ in the NNE affected sector.

It should be noted that for zero averages included, only the 0.5 percentile level has non-zero relative concentrations for all sectors.

Many of the sectors have zero values at the 5 percentile level, while all the relative concentrations are zero at the 50 percentile 'level (median x/9 at the LPZ for all directions is zero). This is the reason for considering only those observations that were in the sectors of interest (excluding zero averages) for these percentile levels. The 2-9 Dames 8 moore

relative concentrations with zero values excluded will always be greater than or equal to the corresponding relative concentrations in-cluding zero values.

A summary of the maximum relative concentrations for Tables 2 .0-3 through 2.0-5 is provided in Table 2.0-6. This table presents the maximum values for the various time periods and percentile levels.

2-10 Dames 8 Moore

2.5 5X OVERALL SITE x/9 VALUES The relative concentrations for the 0-2 hour time period that are exceeded no more than 5 percent of the total time (independent of direction) for both the exclusion area boundary (EAB) and the low population zone (LPZ) were determined by the method presented in Regulatory Guide 1.145 and are presented in Table 2.0-1. These values are identified as the 5X Overall Site x/l} values. The 5X Overall Site X/g values are summarized below (sec/m ):

EAB Distance LPZ Distance 5X Overall Site X/g 9.38E-5 9.04E-5 For the LPZ, 5X Overall Site X/9 values were also determined for the longer accident time periods through logarithmic interpolation between the value presented above plotted at 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> and the maximum of the 16 annual average x/(} values plotted at 8760 hours0.101 days <br />2.433 hours <br />0.0145 weeks <br />0.00333 months <br />. These values .

are presented in Table 2.0-7. The maximum annual average relative concentration for the all directions case occurred in both the NW and SE affected sectors.

Dames R Moore

2.6

SUMMARY

OF SHORT-TERM ACCIDENT DIFFUSION ESTIMATES Regulatory Guide 1.145 provides criteria for short-term diffusion calculations and defines various diffusion estimates that are needed for the evaluation of sites. These values consist of:

Sector x/g - The relative concentration in each wind direction sector that is exceeded 0.5 percent of the total time.

'aximum Sector X/g - The highest of the 16 Sector x/(}'s.

5X Overall Site x/g - The relative 'concentration that is ex-ceeded 5 percent of the total time for aI'l direc-tions combined.

The larger of the Maximum Sector X/g and 5X Overall Site X/g should be used for evaluations (Evaluation X/g) at both the EAB and LPZ. (All direct'ion dependent sector values should be presented for considera--

tion.) Also, for the LPZ, relative concentrations should be determined for various time periods throughout the course of an accident. A sum-mary of the relative concentrations of interest, as defined in Regula-tory Guide 1.145, is pre'sented in Table 2.0-8. Also identified in this table are the previous tables from which these values were obtained.

Regulatory Guide 1.145 indicates that the higher of the Maximum Sector x/g and the 5X Overall Site z/g should be used for EAB and outer LPZ boundary evaluations. The direction dependent values used to obtain the Maximum Sector X/g value are presented in Table 2.0-3. The X/g values to be used for both the EAB and LPZ evaluations, including values for the required time periods to 30 days (LPZ only), are pre-sented in Table 2.0-8. During the September 1976-August 1978 data period, the Maximum Sector x/g values were the governing values for all distances and time periods of interest. All of the Maximum Sector X/g values occurred in either the ESE or SE affected sectors.

2-12 Dames & moore

Table 2.0-9 presents the Maximum Sector X/g values reported in the St. Lucie Unit 2 Final Safety Analysis Report (FSAR) for comparison to the values obtained in this analysis. The Maximum Sector X/9 values have been found to be larger than the 5X Overall Site X/g values and, therefore, the Evaluation x/g values for this site. Comparison of these two sets of Maximum Sector /g values shows that the values for the updated analysis are larger than those presented in the FSAR. The increase in Maximum Sector x/g values range from a factor of about 4 to less than 10 percent dependency on the averaging period. Specifically at the EAB, the Maximum Sector X/g increased from a value of 1.2E-4 reported in the FSAR to 1.6E-4 in this analysis. Although this analy-sis contains two modifications in methodology when compared to that used in the FSAR (Regulatory Guide 1.145 methodology plus a reduced meander consideration), the increase in relative concentration was ex-pected because of the reduced meander term in the computational technique.

2-13 Dames 8 Moon

TABLE 2.0-1

~ ~

SELECTED PERCENTILE VALUES OF HOURLY RELATIVE CONCENTRATIONS*

Data Period: 1 September 1976 - 31 August 1978 5X Level 50K Level EAB 9.39E-5 2.54E-5 Maximum Value 1. 13E-3 (E affected sector)

LPZ 9.04E-5 2.43E-5 Maximum Value 1.10E-3 (E affected sector)

• Seconds per cubic meter.

TABLE 2.0-2 SECTOR x/Q VALUES Oata Period: 1 September 1976 - 31 August 1978 EAB LPZ 0.5X 0.5X x/Q 0-2 Hours x/Q'-2 Affected Sector Hours NNE 6.86E-'5 6.62E-5 NE 8.26E-5 8.00E-5 ENE 9.38E-5 9.04E-5 E 9.38E-5 9.04E-5 ESE 1.64E-4 1.59E-4 SE 1.47E-4 1.43E-4 SSE 8.26E-5 8.00E-5 S 6.26E-5 6.03E-5 SSW 6.26E-5 6.03E-5 SW 4.69E-5 4.52E-5 WSW 4.69E-5 4.52E-5 W 4.69E-5 4.52E-5 WNW 6.26E-5 6.03E-5 NW 6.35E-5 6.07E-5 NNW 6.86E-5 6.62E-5 N 6.26E-5 6.03E-S Maximum Sector x/Q 1.64E-4 1.59E-4

TABLE 2.0-3 RELATIVE CONCENTRATIONS FOR VARIOUS AVERAGING PERIODS (SECTOR X'/g VALUES) LOW POPULATION ZONE: 0.5 PERCENTILE VALUES ZERO AVERAGES INCLUDED Data Period: 1 September 1976 - 31 August 1978 Relative Concentrations (sec/cubic meter)

Avera in Period (hours Affected Sector 16 72 624 NNE 6.62E-5 3.40E-5 2.41E-5 1.15E-5 4.10E-6 NE 8.00E-5 4.00E-5 2.88E-5 1.38E-5 4.30E-6 ENE 9.04E-5 . 4.10E-5 2.87E-5 1.24E-5 3.80E-6 E 9.04E-5 4. 10E-5 2.87E-5 1.26E-5 3.84E-6 ESE 1.59E-4 7.10E-5 4.70E-5 1.97E-5 5.60E-6 SE 1.43E-4 6.70E-5 4.50E-5 2.02E-5 6.10E-6 SSE 8.00E-5 3.90E-5 2.77E-5 1.29E-5 4.30E-6 S 6.03E-.5 2.80E-5 1.93E-5 8.60E-6 2.61E-6 SSW 6.03E-5 2.72E-5 1.84E-5 7:95E-6 2.36E-6 SW 4.52E-5 2. 18E-5 1.52E-5 7.00E-6 2.27E-6 WSW 4.52E-5 2.27E-5 1.60E-5 7.50E-6 2.50E-6 W 4.52E-5 2.29E-5 . .1.62E ..7.80E-6 2.68E-6 WNW 6.03E-5 3.19E-5 2.32E-5 1.17E-5 4.39E-6 NW 6.07E-5 3.27E-5 2.38E-5 1. 21E-5 4.57E-6 NNW 6.62E-5 3.44E-5 2.48E-5 1.23E-5 4.50E-6

.. N 6.03E.-5 3.00E-5 2. 12E-5 1. 00E-5 3.40E-6

TABLE 2.0-4 RELATIVE CONCENTRATIONS FOR VARIOUS AVERAGING PERIODS LOW POPULATION ZONE: 5.0 PERCENTILE VALUES ZERO AVERAGES EXCLUDED Data Period: 1 September 1976 31 August 1978 Relative Concentrations (sec/cubic meter)

Affected Avera in Period hours Sector 72 624 NNE, 8.30E-5 4.07E-5 2.84E-5 1. 31E-5 4. 32E-6 NE 9.61E-5 4.79E-5 3.33E-5 1.58E-5 5. 10E-6

'NE 1.70E-4 7.17E-5 4.62E-5 1. 81E-5 4.72E-6 E 1.91E-4 8.07E-5 5.20E-5 2.02E-5 5.26E-6.-

ESE 2.09E-4 9.00E-5 5.87E-5 2.34E-5 6.21E-6 SE 1.66E-4 7.40E-5 4.98E-5 2.09E-5 6 ~ OOE-6 SSE 9.66E-5 4.59E-5 3.17E-5 1.43E-5 4.53E-6 S 7.96E-5 -. 3.58E-5 - 2.39E-5 1. 01E-5 2.88E-6'.70E-6 SSW 7.98E-5 3.49E-5 2.32E-5 9.66E-6 SW 6.92E-5 3.13E-5 2. 10E-5 8.90E-6 2.60E-6 MSW 6.36E-5 2.95E-5 '.04E-5 ,

9.00E-6 2.80E-6

'W 6.97E -3.31E-'5 2.27E.-5 1.00E-5 3.11E-6 WNW 6.76E-5 3.49E-5 2.52E-5 1.24E-5 4.54E-6 NM 7.62E-5 3.90E-5 2.80E-5 1.38E-5 4.90E-6 NNW 7.36E-5 3.76E-5 2.70E-5 1.32E-5 4.66E-6 N 7. 73E-.5 3.65E-5 2.53E-5 1.13E-5 3.50E-6

TABLE 2.0-5 RELATIVE CONCENTRATIONS FOR VARIOUS AVERAGING PERIODS LOW POPULATION ZONE: 50 PERCENTILE VALUES ZERO AVERAGES EXCLUDED Data Period: 1 September 1976 - 31 August 1978 Relative Concentrations (sec/cubic meter)

Affected Avera in Period (hours Sector 16 72 624 NNE 2.35E-5 1.42E-5 1.10E-5 6.35E-6 2.88E-6 NE 2.92E-5 1.73E-5 1.34E-5 7.68E-6 3.46E-6 ENE 3.63E-5 1.95E-5 1.43E-5 7.39E-6 2.82E-6 E 3.69E 2.02E-5 1.48E-5 7.83E-6 3.00E-6 ESE 3. 81E-5 2. 16E-5 1. 61E-5 8.68E-6 3.55E-.6 SE 3. 14E-5 1.85E-5 1.46E-5 8.25E-6 3.78E-6 SSE 2.68E-5 1.58E-5 1.22E-5 6.85E-6 3.00E-6 S 1. 61E-.5: 9. 40E-6 7. 18E-6 4.00E-6 1.72E-6 SSW 1.98E-5 1.09E-5 8.17E-6 4.35E-6 1.73E-6 SW 1.64E-5 9.40E-6 7.07E-6 3.88E-6 1.63E-6 WSW 1.81E-5 1.07E-5 8.05E-6 4.47E-6 1.89E-6 W 2.03E-5 -

1.19E-5 -

9.03E 4.95E-6 2.12E-6 WNW 2. 25E-5 1.42E-5 1.12E-5 6.67E-6 3. 19E-6 NW 2.74E-5 1.68E-5 1. 31E-5 7.67E-6 3.57E-6 NNW 2.58E-5 1. 58E-5 1.23E-5 7.23E-6 3.38E-6 N 2.65E-,.5 ., ',l. 51E-5 1.15E-5 6.23E-6 2.60E-6

TABLE 2.0-6 MAXIMUM RELATIVE CONCENTRATION VALUES*

FOR VARIOUS AVERAGING TIMES; LOW POPULATION ZONE Data Period: 1 September 1976 - 31 August 1978 0.5X Level** 5X Level 50K Level 2 Hours 15.9 (ESE) 20.90 (ESE) 3.81 (ESE) 8 Hours 7.10 (ESE) 9.00 (ESE) 2.16 (ESE) 16 Hours 4.70 (ESE) 5.87 (ESE) 1.61 (ESE) 72 Hours 2.02 (SE) 2.34 (ESE) 0.87 (ESE) 624 Hours .0.61 (SE) 0.62 (ESE) 0.38 (SE)

• Directions are sector affected; concentrations should be multiplied by .10 to .obtain values in seconds per cubic meter.

• • Maximum Sector y/g values.

TABLE 2.0-7 5X OVERALL SITE x/Q VALUES FOR L'OM 'POPULATION ZONE Data Period: 1 September 1976 31 August 1978 5X Overall Site x/(}

LPZ fAB 2 Hours 9.04E-5 9.38E-5 8 Hours 4.58E-5 16 Hours 3.21E-5 72 Hours 1.53E-5 624 Hours 5.20E-6 Maximum Annual Average 1. 4E-6 (W 5 SE affected sectors)

TABLE 2.0-8 REGtjLATORY GUIDE 1.145 RELATIVE CONCENTRATIONS OF INTEREST (sec/m )

Data Period: 1 September 1976 - 31 August 1978 Di stances*

EAB LPZ LPZ LPZ LPZ  : LPZ Hours

'-2 0-2 Hours 0-8 Hours 8-24 Hours 1-4 Da s Table 2.0-3

~4-3tl 3 Table 2.0-3

~

Sector x/Q Table 2.0-2 Table 2.0-2 Table 2.0-3 Table 2.0-3 Maximum Sector gQ 1.64E-4 (ESE) 1.59E-4 (ESE) 7.10E-5 (ESE) 4.70E-5 (ESE) 2.02E-5 (SE).- 6.10E-6 (SE)

(Affected Sector) (Table 2.0-2) (Table 2.0-2) (Table 2.0-6) (Table 2.0-6) (Table 2.0-6) (Table 2.0-6) 5X Overall Site 9.38E-5 9.04E-5 4.58E-5 3.21E-5 1.53E-5 5.20E-6 X/Q (Table 2.0-1) (Table 2.0-1) (Table 2.0-7) (Table 2.0-7) (Table 2.0-7) (Table 2.0-7)

Evaluation x/Q 1.64E-4 1.59E-4 7. 10E-5 4.70E-5 2.02E-5 6.10E-6

• EAB = Exclusion Area Boundary LPZ = Low Population Zone

TABLE 2.0-9 MAXIMUM SECTOR  :/Q VALUES FROM THE ST. LUCIE- UNIT 2 FINAL SAFETY ANALYSIS REPORT Data Period: 1 September 1976 - 31 August 1978 Distances*

EAB LPZ LPZ LPZ LPZ LPZ 0-2 Hours Hours

'-2 0-8 Hours 8-24 Hours 1-4 Da s 4-30 Da s Maximum Sector x/Q 1.2E-4 (SE) 1.1E-4 (SE) 6.6E-5 (ESE) 1.2E-5 (ESE, SE) 5.8E-6 (SE). 3.0E-6 (SE)

(Affected Sector) (Table 2.3-101)**(Table 2.3-101) (Table 2.3-101) (Table 2.3-101) (Tabl e 2.3-101) (Table 2.3-101)

• EAB = Exclusion Area Boundary LPZ - Low Population Zone

• • Table number from FSAR

IO Stabi lit y Gloss 5

O 4

4.

0 E I-CP UJ O

2 3 4 5 6 7 8 9 lo WINDSPEED (m/sec)

Figure 2.0-1. Correction Factors for Pasquill-Gifford ~y Values by Atrospheric Stability Class (Regulatory Guide 1.145)