RRFM 2009 Transactions - European Nuclear Society

0.E+00
2.E+06
1.40E+07
2.E+06
1.20E+07
1.40E+07
2.E+06
1.20E+07
1.E+06
1.00E+07
1.00E+07
Activity (Ci)
1.E+06
1.E+06
8.E+05
HEU
LEU
Activity (Ci)
8.00E+06
6.00E+06
HEU
LEU
Activity (Ci)
8.00E+06
6.00E+06
HEU
LEU
6.E+05
4.00E+06
4.00E+06
4.E+05
2.E+05
2.00E+06
2.00E+06
0.00E+00
0.00E+00
kr 81 kr 83m kr 85 kr 85m kr 87
xe127 xe129m xe131m xe133 xe133m xe135 xe135m
i129 i130 i131 i132 i133 i133m i134 i135
Fig 2. Comparative results for HEU and LEU fuel content of noble gases and iodine
It’s easy to see that the radioactive inventory in the fuel is considerably higher for the LEU
fuel (with a factor of 10 to 10 3 ). Source term for the accident consequences evaluation was
carried out based on the assumptions presented above.
Were also performed calculation for doses and associated risks. The results for the mean 1-
day individual effective dose and mean 1-day individual thyroid dose are presented in Figure
3 and figure 4 respectively.
Mean 1-day effective individual dose
Mean 1-day thyroid individual dose
1.E-03
1.E-02
HEU
LEU
1.E-03
HEU
LEU
Dose (Sv)
1.E-04
1.E-05
Dose (Sv)
1.E-04
1.E-05
1.E-06
0.1 1 10
Distance (km)
Fig 3. Mean 1-day individual effective dose
1.E-06
0.1 1 10
Distance (km)
Fig 4. Mean 1-day individual thyroid dose
Comparative results for HEU and LEU fuel for organ doses are presented in Figure 5.
mean 1-day organ dose
7.E-04
6.E-04
5.E-04
6.91E-04
HEU
LEU
Dose (Sv)
4.E-04
3.E-04
2.E-04
1.E-04
0.E+00
1.49E-06
6.82E-05
1.62E-05
1.56E-06
7.04E-05
1.22E-06
5.58E-05
2.17E-06
9.71E-05
1.34E-06
6.19E-05
1.24E-06
5.71E-05
LUNG
THYROID
EYE LENS
OVARIES
EFFECTIVE
B. MARROW
GI-TRACT
Fig 5. Mean 1-day individual organ dose
As can be seen from above figures, the doses in the case of LEU fuel are approximately
hundred times higher than for the HEU fuel. The maximum value of the dose (0.14 mSv for
LEU fuel and 0.003 mSv for HEU fuel) is reached at approximately 2.8 km from the point of
release. All the dose calculations were performed considering no implementation of
protective actions. The values for radioactive concentrations in environment and doses to
public are small, so even in this accident situation, the consequences for the public and
environment will be very small.
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