- Email: [email protected]
Calculation of the radioactive releases from the Iran-1 and Iran-2 nuclear power plants
N U C L E A R I N S T R U M E N T S AND METHODS
157 ( 1 9 7 8 )
601-606
; ©
N O R T H - H O L L A N D PUBLISHING CO.
CALCULATION OF THE RADIOACTIVE RELEASES FROM THE IRAN-1 AND IRAN-2 NUCLEAR POWER PLANTS DARIUSH AZIMI-GARAKANI and ARDESHIR GAVIRI
Institute o[' Nuclear Science and Technology, University o[' Tehran, P. O. Box 2989, Tehran, lran Received 3 May 1978 The concentration of radioactive material in air and on the ground surface, released from the normal operation of the Iran-1 and Iran-2 nuclear power plants, is calculated using the AIRDOS computer code. The plants are located in the Halileh site on the coast of the Persian Gulf. These two units are of the Kraftwerk Union standardized PWR type of the 1300 MW class. The time schedule for the first criticality of these two units is mid-1980 and 1981, respectively. The nearest population centre to the site is Bushehr, with a population of - 6 2 000, to the north-west and at a distance of about 18 km from the site. The calculation shows that the concentration of radioactive material in air and the ground surface deposition are higher towards the north-west than any other direction. The annual individual dose rates released from the site are 4.4, 2.3 and 29.8 mrem for the noble gases, aerosols (with half-life longer than 8 days) and radio iodines, respectively.
1. Introduction A large nuclear power plant program has been embarked upon in order to develop Iran into a modern industrial country while protecting the country's large, but finite oil reservoirs. To follow this program, the construction of two nuclear power plants has been started in the southern parts of Iran, on the coast of the Persian Gulf, in 1975. The erection of these two pressurized water reactors (PWR) and prerequisite installations for the connection of two seawater desalination plants are by the German firm Kraftwerk Union AG (KWU) on a turnkey basisl,2). These two units, designated Iran-1 and Iran-2, are of the K W U standardized P W R type of the 1300 MW class3). The units are located in the Halileh site, south of the Bushehr penisula. The site covers an area of about 200 hectars situated right on the coast. The investigations preliminary to site selection were carried out by the American consultants Dames and Moore 4) contracted by KWU. The complete results of these studies have not been published, nor are they generally accessible, but the main points of the Halilelh site can be found elsewherel). ~ One of the main concerns about the operational safety of a nuclear power plant is focused on the continuous releases of radioactive material to the environment. There are several reports 5-8) on the calculation and measurement of atmospheric releases of radionuclides from nuclear reactors. On the turnkey contracts, these calculations are norrnally carried out by the experienced consultants. Nevertheless, in a country like Iran which has just
started an ambitious nuclear program, it is vital that this type of study be undertaken by university researchers in order to develop national capability in this field of nuclear technology. This paper describes the calculation of atmospheric releases from the Iran-1 and Iran-2 nuclear power plants using the AIRDOS computer code9). 2. Site characteristics The southern coastal part of Iran is a plainland with a height of about 500 m above sea level. The N 25"/*
\
\ W
/ /
3.5-5.0 5.5-I0.0
m/$ Fig. 1. Wind rose presentation at the Halileh site.
602
O. A Z A M I - G A R A K A N I
AND A. G A V I R i
TABLE 1 The Halileh site characteristics.
Characteristic
Description ZERUN
Location Geology and soils
Meteorology
Annual average Annual average temperature Annual average humidity Annual average temperature Salinity
28°51'N-50o51'E Sand, partially claylike with rock. Seismically very active; max. ground acceleration 0.3-0.5 g Desert-like with west and northwest wind directions during most parts of the year rainfall 200-300 mm air 24 °C air 23 % sea 26.5 °C 4.1-4.5%
Ruo
0KHARI( ISLAND
~JAN
f
HALILEE @
(t
dry climate, high temperature and small rainfall throughout the year are the main characteristics of this region. Since the air diffusion pressure in the area is directed from the central parts of Saudi Arabia to the Persian Gulf, the wind direction is towards west and north-west during most seasons. This is an important factor for atmospheric releases from the plant stacks. Fig. 1 shows the wind speed and percentage occurrence of directions (wind rose) at the site4). With long and hot summers, Bushehr is one of the hottest places in the world. The mean temperature varies from about 14 °C in January to about 33 °C in August. The mean daily maximum temperatures are between 40 and 46°C during summers. The variation in seawater temperature is also high throughout the year with 36°C and 13°C for the maximum and minimum, respectively1°). Table 1 shows some of the geographical and environmental characteristics of the Halileh site. The two villages of Halileh, with a population of 690, and Bandargah, with a population of 520, are to the west and south-east and at a distance of 1 and 2 km from the site, respectively. The study of the population distribution around the Halileh site shows ~1) that there are two population centres in the area: Bushehr and Borazjan with populations of 62 000 and 26000, respectively. These two towns are at a distance of about 18 and 50 km from the site, respectively. The locations of the Halileh site and the two population centres are shown in fig. 2.
N
20
10
0
I0
Z0
30
km
Fig, 2. The Halileh site and the population centres of Bushehr and Borazjan.
3. Methods of calculation Calculations were made in order to estimate the atmospheric releases from the Iran-1 and Iran-2 nuclear power plants. In these calculations the AIRDOS computer c o d e 9) w a s used and the concentration of the predominant radionuclides in air and their deposition on the ground surface were calculated. The code is for continuous releases of radionuclides rather than accidental or pulse releases. AIRDOS calculates up to 36 radionuclides releasing from as many as 6 plant stacks. The method of calculation is to consider a 20×20 square grid with the nuclear power plant located at the centre. The input data consist of a meteorological and statistical description of the area as well as parameters used to estimate inhalation doses and doses resulting from submersion in water. Some other parameters such as radionuclide-independent parameters and characteristics of each radionuclide form the rest of the input data. In the calculations the length of each small square was taken as 2 km to permit the study of
RADIOACTIVE
RELEASES
FROM
the atmospheric releases on the Bushehr area. Thus, the total area of the grid is 1600kin 2. About two-thirds of the grid is water and the rest is land. About one-third of the land is inhabited. No inhabited island lies within the grid, i.e., within a radius of about 30 km from the site. Fig. 3 shows the 20 × 20 square grid with the Halileh site at the centre. The grid includes the population of the Bushehr area and that of a strip of villages situated on the east side of the site. The population density of the inhabited areas was assumed to be equally distributed between the adjacent squares, owing to lack of information about the exact population distribution.
NUCLEAR
POWER
PLANTS
4. Results and discussion Atmospheric dispersion and doses resulting from the radioactive material released from the Iran-1 and Iran-2 nuclear power plants were calculated using the AIRDOS computer code. The time schedule for the first criticality of these two units is mid-1980 and 1981, respectively. In the calculations, the main volatile radionuclides released from a typical 1000 MWe P W R were considered~). These radionuclides were noble gases and radioiodines. The average release rates of the noble gases and iodines from the 75 m high plant stack were assumed to be 1 × 10 l°" and 2 × 104 pCi/sec, respectively, the typical values for a PWR of the same size. '.. ."." ;-t.".i' • .-. ....... :..I.-.: I.-
2C
~s7 ~
i
" . ..• . . . . . . ...1
'','
n".
'i'n
""
:.
n.
..
".1.
-.n
i
)~... ~ , r ~ ; ~
i%, I,a, •
...
i
".....
.
-.i.
•
.1"
. .
.'
-
.
...
'
.
...
.•.
.:..,-.:...,.' , . . . . . . . . . . . . . .
'...'
".'.
" •
.
.'.."
.
•
.
-~
.
.'..
~'.
~
.,
•493 .493 4931.~931.493 I . - I , . . I . . . . ~ . . . . = . . . ~
L
L
~
~
I
'..
:
.
"..'1~'..1"..'.1.':'1"
.
.
•
. .'1
' . ~. ' :
'. - '
n I,°,,,0,, "..
" .
•
•
.
."
•
. . .
.
•
,
.
.
n
•
~-.. ' . 2 0 ~ ' . z 0 7 " . . . ".'.1~
•
i||g|Ninlui|au • ..'l'..
"1":"
".1
.'"
'"l"_,, l 'l"l "~- . ~ . i"." ' . ~ ' 6 9 0
:'..'."
..i
-i
'..
•
..
-.
.:.'
...:
.t'.....t."
"u.'..'l
.
.
~....... "":t ..:...:....207.2o~ .-~ ~. ; ~ : i " . " : " ~ . " . . ' , ' . ' . . ' . ' . ""."
..
""':~(.
:
:.".~.
.''"
207
.207
.'.'"
zo~ zo7 ' '.i
~....-' "'."'1
- ""
•
.1".':'-I-''"
..:'.
N
. ..
•
I.'..I " i
..
... .' " ' "2"." '.n.'.'.
..'..
,
.'...
"2; ,,-....
".'-'.'" ,
....,
N if :•
4
2
o
z
4
I
6
km
!
•
Hatiteh
603
Site
Fig. 3. T h e 20 × 20 square grid a r o u n d t h e Halileh site and t h e population distribution.
20
604
D.
AZIMI-GARAKAN1
AND
A.
GAVIRI
%
t-
o
) I
I
I
I
t-
E
o
o r¢-4
z ~
x~
E ©
o
~D ¢J
E
E~c
RADIOACTIVE
RELEASES
FROM
~: The maximum concentration of radioactive material in aji~and their ground surface deposition. ,-. TABLE 2
?
Nuclide
Air concentration (pCi/cm 3)
Ground surface deposition (pCi/cm 2. sec)
85Kr 85mKr 87Kr 88Kr 133Xe 133mXe 135Xe
4.46 E-03 5.19 E-03 2.30 E-02 7.06 E-02 8.41 E-02 4.46 E-02 1.09 E-01 4.90 E-03 8.06 E-02 1.07 E-02
2.32 E-01 2.69 E-01 1.19 E 00 3.67 E 00 4.34 E 00 2.32 E 00 5.61 E 00 2.54 E-01 4.18 E 00 5.53 E 00
135mXe
13~I 1331
TABLE 3 Annual dose estimates from the Iran-1 and Iran-2 nuclear power plants.
Source term
Noble gases Aerosols* Radioiodines
Dose (torero) 4.4 2.3 29.8 (thyroid)
* Half-life longer than 8 days. The calculations showed that the concentration of radioactive material in air and the ground surface deposition is higher towards the north-west, where the Bushehr population centre is located, than any other direction, This may be one o f the disadvantages of the Halileh site. T h e results also show that the m a x i m u m contamination is in the square grid (fig. 3) identified by the c o l u m n and row numbers 10 and 11, respectively, while the m i n i m u m value for the same radionuclides is in the top right corner square of the grid. Table 2 shows the m a x i m u m contamination o f radioactive material in air and on the ground surface. A typical contamination distribution of 133Xe in air and on the ground surface released from the Iran-1 and Iran-2 nuclear power plants is shown in fig. 4. Similar curves were obtained for the rest of the nuclides. T h e curves represent the isopleths o f the atmospheric diffusion from the Halileh site. T h e s u m m a r y of the estimated annual doses to any organ from all pathways is shown in table 3.
NUCLEAR
POWER
PLANTS
605
It should be noted that some of the parameters for the AIRDOS input data such as p l u m e rise, vertical temperature gradient for Pasquill categories and the gravitation fall velocity for each nuclide were taken from the iiterature~2-14), owing to lack of regional information. Nevertheless, a good comparison is expected between the calculated and measured atmospheric dispersion and dose rates from the Iran-1 and Iran-2 nuclear power plants. W h e t h e r this estimate is optimistic remains to be seen. 5. Conclusions Calculations were carried out to estimate the concentration of radioactive material in air and their ground surface deposition released from the normal operation of the Iran-1 and Iran-2 nuclear power plants. In this estimation the AIRDOS computer code was used and the annual dose rates were also calculated. The input data of the code were the meteorological and statistical description o f the area as well as radionuclide-independent parameters and the parameters related to the radionuclide characteristics. In the calculations the main volatile radionuclides released from a typical 1 0 0 0 M W e P W R were considered. T h e results showed that the contamination in air and on the ground surface is higher towards the north-west of the site, where the Bushehr population centre is located, than any other direction. The annual individual dose rates released from the site are 4.4, 2.3 and 29.8 m r e m for the noble gases, aerosols (with half-life longer than 8 days) and radioiodines, respectively.
References 1) w. Altvater, Atomwirtschaft 22, no. 2 (Feb. 1977) 74. 2) lran plans world's fourth biggest nuclear programme, Nucl. Eng. Int. 22, no. 254 (Mar. 1977) 31. 3) H. Fruhauf and G. Lepie, Nucl. Eng. Int. 20, no. 233 (Aug. 1975) 607. 4) Site Validation Studies, Proposed Nuclear Power Plant near Bushehr, Iran (July 1975), Dames&Moore Consulting Engineers in Environmental and Applied Earth Sciences, Tehran, Iran. 5) Geoffery G. Eichholz, Environmental aspects of nuclear power (Ann Arbor Science Publishers, Ann Arbor, 1976). 6) j. H. Rust and L. E. Weaver (Ed.), Nuclear power safe(v (Pergamon Press, New York, 1976). 7) F. R. Farmer (Ed.), Nuclear reactor safety (Academic Press, New York, 1977). 8) R. H. Clarke, J. Fitzparrick, A. J. H. Goddard and M. J. Henning, J. Br. Nucl. Energy Soc. 15, no. 4 (1976) 297.
606
D. A Z A M I - G A R A K A N I AND A. GAVIRI
9) R. E. Moore. Oak Ridge Nat. Lab., Report ORNL-TM4687, Environm. Sci. Div., Publ. no. 654 (Jan. 1975). 10) A. Khalili, J. Earth Space Phys. (Tehran Univ. Inst. Geophys.) 5 (1976) 34. tl) Statistical Yearbook, lran Statistics Centre, Plan and Budget Organization, Tehran (Jan. 1977). 12) D. N. Slade (Ed.), Meteorology and atomic energy - - 1968, U.S. Atomic Energy Commission/Division of Technical
Information (July 1968). 13) G. A. Briggs, Plume rise, AEC Critical Review Series, TID25075 (Nov. 1968). 14) R. S. Booth, S. V. Kaye and P. S. Rohwer, in Proc. Third Nat. Symp. on Radioecology, May 10-12, 1971, Oak Ridge, Tennessee, D. J. Nelson (Ed.), CONF-710501 (ORNL, Oak Ridge, 1971) p. 877.
157 ( 1 9 7 8 )
601-606
; ©
N O R T H - H O L L A N D PUBLISHING CO.
CALCULATION OF THE RADIOACTIVE RELEASES FROM THE IRAN-1 AND IRAN-2 NUCLEAR POWER PLANTS DARIUSH AZIMI-GARAKANI and ARDESHIR GAVIRI
Institute o[' Nuclear Science and Technology, University o[' Tehran, P. O. Box 2989, Tehran, lran Received 3 May 1978 The concentration of radioactive material in air and on the ground surface, released from the normal operation of the Iran-1 and Iran-2 nuclear power plants, is calculated using the AIRDOS computer code. The plants are located in the Halileh site on the coast of the Persian Gulf. These two units are of the Kraftwerk Union standardized PWR type of the 1300 MW class. The time schedule for the first criticality of these two units is mid-1980 and 1981, respectively. The nearest population centre to the site is Bushehr, with a population of - 6 2 000, to the north-west and at a distance of about 18 km from the site. The calculation shows that the concentration of radioactive material in air and the ground surface deposition are higher towards the north-west than any other direction. The annual individual dose rates released from the site are 4.4, 2.3 and 29.8 mrem for the noble gases, aerosols (with half-life longer than 8 days) and radio iodines, respectively.
1. Introduction A large nuclear power plant program has been embarked upon in order to develop Iran into a modern industrial country while protecting the country's large, but finite oil reservoirs. To follow this program, the construction of two nuclear power plants has been started in the southern parts of Iran, on the coast of the Persian Gulf, in 1975. The erection of these two pressurized water reactors (PWR) and prerequisite installations for the connection of two seawater desalination plants are by the German firm Kraftwerk Union AG (KWU) on a turnkey basisl,2). These two units, designated Iran-1 and Iran-2, are of the K W U standardized P W R type of the 1300 MW class3). The units are located in the Halileh site, south of the Bushehr penisula. The site covers an area of about 200 hectars situated right on the coast. The investigations preliminary to site selection were carried out by the American consultants Dames and Moore 4) contracted by KWU. The complete results of these studies have not been published, nor are they generally accessible, but the main points of the Halilelh site can be found elsewherel). ~ One of the main concerns about the operational safety of a nuclear power plant is focused on the continuous releases of radioactive material to the environment. There are several reports 5-8) on the calculation and measurement of atmospheric releases of radionuclides from nuclear reactors. On the turnkey contracts, these calculations are norrnally carried out by the experienced consultants. Nevertheless, in a country like Iran which has just
started an ambitious nuclear program, it is vital that this type of study be undertaken by university researchers in order to develop national capability in this field of nuclear technology. This paper describes the calculation of atmospheric releases from the Iran-1 and Iran-2 nuclear power plants using the AIRDOS computer code9). 2. Site characteristics The southern coastal part of Iran is a plainland with a height of about 500 m above sea level. The N 25"/*
\
\ W
/ /
3.5-5.0 5.5-I0.0
m/$ Fig. 1. Wind rose presentation at the Halileh site.
602
O. A Z A M I - G A R A K A N I
AND A. G A V I R i
TABLE 1 The Halileh site characteristics.
Characteristic
Description ZERUN
Location Geology and soils
Meteorology
Annual average Annual average temperature Annual average humidity Annual average temperature Salinity
28°51'N-50o51'E Sand, partially claylike with rock. Seismically very active; max. ground acceleration 0.3-0.5 g Desert-like with west and northwest wind directions during most parts of the year rainfall 200-300 mm air 24 °C air 23 % sea 26.5 °C 4.1-4.5%
Ruo
0KHARI( ISLAND
~JAN
f
HALILEE @
(t
dry climate, high temperature and small rainfall throughout the year are the main characteristics of this region. Since the air diffusion pressure in the area is directed from the central parts of Saudi Arabia to the Persian Gulf, the wind direction is towards west and north-west during most seasons. This is an important factor for atmospheric releases from the plant stacks. Fig. 1 shows the wind speed and percentage occurrence of directions (wind rose) at the site4). With long and hot summers, Bushehr is one of the hottest places in the world. The mean temperature varies from about 14 °C in January to about 33 °C in August. The mean daily maximum temperatures are between 40 and 46°C during summers. The variation in seawater temperature is also high throughout the year with 36°C and 13°C for the maximum and minimum, respectively1°). Table 1 shows some of the geographical and environmental characteristics of the Halileh site. The two villages of Halileh, with a population of 690, and Bandargah, with a population of 520, are to the west and south-east and at a distance of 1 and 2 km from the site, respectively. The study of the population distribution around the Halileh site shows ~1) that there are two population centres in the area: Bushehr and Borazjan with populations of 62 000 and 26000, respectively. These two towns are at a distance of about 18 and 50 km from the site, respectively. The locations of the Halileh site and the two population centres are shown in fig. 2.
N
20
10
0
I0
Z0
30
km
Fig, 2. The Halileh site and the population centres of Bushehr and Borazjan.
3. Methods of calculation Calculations were made in order to estimate the atmospheric releases from the Iran-1 and Iran-2 nuclear power plants. In these calculations the AIRDOS computer c o d e 9) w a s used and the concentration of the predominant radionuclides in air and their deposition on the ground surface were calculated. The code is for continuous releases of radionuclides rather than accidental or pulse releases. AIRDOS calculates up to 36 radionuclides releasing from as many as 6 plant stacks. The method of calculation is to consider a 20×20 square grid with the nuclear power plant located at the centre. The input data consist of a meteorological and statistical description of the area as well as parameters used to estimate inhalation doses and doses resulting from submersion in water. Some other parameters such as radionuclide-independent parameters and characteristics of each radionuclide form the rest of the input data. In the calculations the length of each small square was taken as 2 km to permit the study of
RADIOACTIVE
RELEASES
FROM
the atmospheric releases on the Bushehr area. Thus, the total area of the grid is 1600kin 2. About two-thirds of the grid is water and the rest is land. About one-third of the land is inhabited. No inhabited island lies within the grid, i.e., within a radius of about 30 km from the site. Fig. 3 shows the 20 × 20 square grid with the Halileh site at the centre. The grid includes the population of the Bushehr area and that of a strip of villages situated on the east side of the site. The population density of the inhabited areas was assumed to be equally distributed between the adjacent squares, owing to lack of information about the exact population distribution.
NUCLEAR
POWER
PLANTS
4. Results and discussion Atmospheric dispersion and doses resulting from the radioactive material released from the Iran-1 and Iran-2 nuclear power plants were calculated using the AIRDOS computer code. The time schedule for the first criticality of these two units is mid-1980 and 1981, respectively. In the calculations, the main volatile radionuclides released from a typical 1000 MWe P W R were considered~). These radionuclides were noble gases and radioiodines. The average release rates of the noble gases and iodines from the 75 m high plant stack were assumed to be 1 × 10 l°" and 2 × 104 pCi/sec, respectively, the typical values for a PWR of the same size. '.. ."." ;-t.".i' • .-. ....... :..I.-.: I.-
2C
~s7 ~
i
" . ..• . . . . . . ...1
'','
n".
'i'n
""
:.
n.
..
".1.
-.n
i
)~... ~ , r ~ ; ~
i%, I,a, •
...
i
".....
.
-.i.
•
.1"
. .
.'
-
.
...
'
.
...
.•.
.:..,-.:...,.' , . . . . . . . . . . . . . .
'...'
".'.
" •
.
.'.."
.
•
.
-~
.
.'..
~'.
~
.,
•493 .493 4931.~931.493 I . - I , . . I . . . . ~ . . . . = . . . ~
L
L
~
~
I
'..
:
.
"..'1~'..1"..'.1.':'1"
.
.
•
. .'1
' . ~. ' :
'. - '
n I,°,,,0,, "..
" .
•
•
.
."
•
. . .
.
•
,
.
.
n
•
~-.. ' . 2 0 ~ ' . z 0 7 " . . . ".'.1~
•
i||g|Ninlui|au • ..'l'..
"1":"
".1
.'"
'"l"_,, l 'l"l "~- . ~ . i"." ' . ~ ' 6 9 0
:'..'."
..i
-i
'..
•
..
-.
.:.'
...:
.t'.....t."
"u.'..'l
.
.
~....... "":t ..:...:....207.2o~ .-~ ~. ; ~ : i " . " : " ~ . " . . ' , ' . ' . . ' . ' . ""."
..
""':~(.
:
:.".~.
.''"
207
.207
.'.'"
zo~ zo7 ' '.i
~....-' "'."'1
- ""
•
.1".':'-I-''"
..:'.
N
. ..
•
I.'..I " i
..
... .' " ' "2"." '.n.'.'.
..'..
,
.'...
"2; ,,-....
".'-'.'" ,
....,
N if :•
4
2
o
z
4
I
6
km
!
•
Hatiteh
603
Site
Fig. 3. T h e 20 × 20 square grid a r o u n d t h e Halileh site and t h e population distribution.
20
604
D.
AZIMI-GARAKAN1
AND
A.
GAVIRI
%
t-
o
) I
I
I
I
t-
E
o
o r¢-4
z ~
x~
E ©
o
~D ¢J
E
E~c
RADIOACTIVE
RELEASES
FROM
~: The maximum concentration of radioactive material in aji~and their ground surface deposition. ,-. TABLE 2
?
Nuclide
Air concentration (pCi/cm 3)
Ground surface deposition (pCi/cm 2. sec)
85Kr 85mKr 87Kr 88Kr 133Xe 133mXe 135Xe
4.46 E-03 5.19 E-03 2.30 E-02 7.06 E-02 8.41 E-02 4.46 E-02 1.09 E-01 4.90 E-03 8.06 E-02 1.07 E-02
2.32 E-01 2.69 E-01 1.19 E 00 3.67 E 00 4.34 E 00 2.32 E 00 5.61 E 00 2.54 E-01 4.18 E 00 5.53 E 00
135mXe
13~I 1331
TABLE 3 Annual dose estimates from the Iran-1 and Iran-2 nuclear power plants.
Source term
Noble gases Aerosols* Radioiodines
Dose (torero) 4.4 2.3 29.8 (thyroid)
* Half-life longer than 8 days. The calculations showed that the concentration of radioactive material in air and the ground surface deposition is higher towards the north-west, where the Bushehr population centre is located, than any other direction, This may be one o f the disadvantages of the Halileh site. T h e results also show that the m a x i m u m contamination is in the square grid (fig. 3) identified by the c o l u m n and row numbers 10 and 11, respectively, while the m i n i m u m value for the same radionuclides is in the top right corner square of the grid. Table 2 shows the m a x i m u m contamination o f radioactive material in air and on the ground surface. A typical contamination distribution of 133Xe in air and on the ground surface released from the Iran-1 and Iran-2 nuclear power plants is shown in fig. 4. Similar curves were obtained for the rest of the nuclides. T h e curves represent the isopleths o f the atmospheric diffusion from the Halileh site. T h e s u m m a r y of the estimated annual doses to any organ from all pathways is shown in table 3.
NUCLEAR
POWER
PLANTS
605
It should be noted that some of the parameters for the AIRDOS input data such as p l u m e rise, vertical temperature gradient for Pasquill categories and the gravitation fall velocity for each nuclide were taken from the iiterature~2-14), owing to lack of regional information. Nevertheless, a good comparison is expected between the calculated and measured atmospheric dispersion and dose rates from the Iran-1 and Iran-2 nuclear power plants. W h e t h e r this estimate is optimistic remains to be seen. 5. Conclusions Calculations were carried out to estimate the concentration of radioactive material in air and their ground surface deposition released from the normal operation of the Iran-1 and Iran-2 nuclear power plants. In this estimation the AIRDOS computer code was used and the annual dose rates were also calculated. The input data of the code were the meteorological and statistical description o f the area as well as radionuclide-independent parameters and the parameters related to the radionuclide characteristics. In the calculations the main volatile radionuclides released from a typical 1 0 0 0 M W e P W R were considered. T h e results showed that the contamination in air and on the ground surface is higher towards the north-west of the site, where the Bushehr population centre is located, than any other direction. The annual individual dose rates released from the site are 4.4, 2.3 and 29.8 m r e m for the noble gases, aerosols (with half-life longer than 8 days) and radioiodines, respectively.
References 1) w. Altvater, Atomwirtschaft 22, no. 2 (Feb. 1977) 74. 2) lran plans world's fourth biggest nuclear programme, Nucl. Eng. Int. 22, no. 254 (Mar. 1977) 31. 3) H. Fruhauf and G. Lepie, Nucl. Eng. Int. 20, no. 233 (Aug. 1975) 607. 4) Site Validation Studies, Proposed Nuclear Power Plant near Bushehr, Iran (July 1975), Dames&Moore Consulting Engineers in Environmental and Applied Earth Sciences, Tehran, Iran. 5) Geoffery G. Eichholz, Environmental aspects of nuclear power (Ann Arbor Science Publishers, Ann Arbor, 1976). 6) j. H. Rust and L. E. Weaver (Ed.), Nuclear power safe(v (Pergamon Press, New York, 1976). 7) F. R. Farmer (Ed.), Nuclear reactor safety (Academic Press, New York, 1977). 8) R. H. Clarke, J. Fitzparrick, A. J. H. Goddard and M. J. Henning, J. Br. Nucl. Energy Soc. 15, no. 4 (1976) 297.
606
D. A Z A M I - G A R A K A N I AND A. GAVIRI
9) R. E. Moore. Oak Ridge Nat. Lab., Report ORNL-TM4687, Environm. Sci. Div., Publ. no. 654 (Jan. 1975). 10) A. Khalili, J. Earth Space Phys. (Tehran Univ. Inst. Geophys.) 5 (1976) 34. tl) Statistical Yearbook, lran Statistics Centre, Plan and Budget Organization, Tehran (Jan. 1977). 12) D. N. Slade (Ed.), Meteorology and atomic energy - - 1968, U.S. Atomic Energy Commission/Division of Technical
Information (July 1968). 13) G. A. Briggs, Plume rise, AEC Critical Review Series, TID25075 (Nov. 1968). 14) R. S. Booth, S. V. Kaye and P. S. Rohwer, in Proc. Third Nat. Symp. on Radioecology, May 10-12, 1971, Oak Ridge, Tennessee, D. J. Nelson (Ed.), CONF-710501 (ORNL, Oak Ridge, 1971) p. 877.