Comparison of radioactive contamination
between Chernobyl and Fukushima
Chernobyl April 1986

Fukushima March 2011

Imanaka T.
Research Reactor Institute, Kyoto University
June 27, 20121

チェルノブイリ型原発（左）と福島型原発（右）RBMK

黒鉛減速沸騰軽水冷却チャンネル炉BWR

軽水減速沸騰軽水冷却
圧力容器炉

2

“Period after Fukushima”began also in Japan

Significant contamination
with radiocesiums occurredalong the coast of thenorthern half of Honshu
island.

3

4

Fukushima and Chernobyl- Evacuation area near NPP 26 years after Chernobyl

Fukushima

ベラルーシ

立入禁止区域

60 km

30 km

ウクライナ

キエフ貯水湖

チェルノブイリ周辺立入禁止区域

Both accidents indicate consequences of the worst
situation at NPP that core radioactivity in thecore was directly released into the environment.
5

ChernobylApril 261986

Чернобыльский репортаж (1988)

6

In-air explosion opinion by Checherov

Checherovら
2005

7Radioactivity release70④ 4/27-28

放射能放出量（ＭＣｉ）

60③ 4/27-28

50⑤ 4/2840①4/26② 4/26-27

30⑥ 4/29

20
10
0

⑧ 5/2
4/26 4/27 4/28 4/29 4/30 5/1 5/2 5/3 5/4 5/5 5/6

1986

Daily release (without rare gases)
Based on 1986 USSR report.

⑦ 4/295/1
Direction of radioactive plumes．
Izrael（2005.12 Moscow）．
8

Radiation situation on June 1, 1986

Kozubovら 1991

Red color indicates “Red forest”

10チェルノブイリ原発周辺10km
プリピャチ川○ ウソフ村○クラースノエ村

プリピャチ市○

シェペレチ村○ジモビシチェ村

５

ヤノフ駅

○

３

クリバヤ・ゴラ村

１

５

１ｋｍ

１．１～４号炉（４号炉は西端）
２．５，６号炉（事故当時建設中）
３．取水路
４．放水路
５．引き込み線路
実線は道路

４冷却池

２

○

チスタゴルフカ村○○

スタロセル村

コパチ村

○

レレフ村

プリピャチ市より 2005年10月
11Radiation dose in the 30km zone
May 1, 1986、μSv/hBaliffら 1996
12

チェルノブイリでは出力暴走により原子炉と建屋が爆発・炎上
２年後、TVカメラを入れてみると炉心は空っぽだったЧернобыльский репортаж (1988)

13

Fukushima accident

美浜の会ホームページ
14March12,Hydrogen
explosion #1
March14,Hydrogen
explosion #3
15

March 15, Containment failure #2

16

Containment pressure and radiation
monitoring data at NPPTEPCO Interim report, Dec. 201117

Daily release from NPP
放 射 能 放 出 量 , P B q/day

70
60

I-131

50

Cs134+Cs137

40
30
20
10

12日
13日
14日
15日
16日
17日
18日
19日
20日
21日
22日
23日
24日
25日
26日
27日
28日
29日
30日
31日

0

2011年3月
Fig.4. Daily release of I-131 and Cs-137+Cs134 from the Fukushima Daiichi NPPaccident up to March 31. Daily values are calculated form the results by Chino et al[8],assuming the same release of Cs-134 as Cs-137.

Prepared by Imanaka
18

About 80,000 people wereevacuated from the 20 km
zone on March 12.
But, no data of radioactive
contamination was released
from the authorities, only
saying “No danger fro publichealth”.
19SPEEDI simulation on March 15

20

50

南相馬市24
飯舘村40
葛尾村26
福島空港58
川内村22
いわき市平
田村市35
田村市40

40
30
20
10

3/25 0:00

3/24 0:00

3/23 0:00

3/22 0:00

3/21 0:00

3/20 0:00

3/19 0:00

3/18 0:00

3/17 0:00

3/16 0:00

3/15 0:00

0
3/14 0:00

空間線量率、マイクロシーベルト／時

飯舘村の放射線レベル

福島県20-30km圏放射線量率の変化：２０１１年３月１５日～

Data from Fukushima prefecture HP

21

Sample Monitoring on March 15ヨウ素131が100万Bq/kgのほうれん
草を100g食べると、10万Bqの取り込み。
それが乳児であれば、甲状腺の等価線量は。2.8×10-3[mSv/Bq]×105[Bq]＝280mSvとなる。
Data from HP
22Knowing that awful
contamination occurred outside
30 km zone, no warning wasissued from the authorities.
Imanaka supposed that
headquarters of our government
also melted down as well as threereactors in Fukushima.
23

Radiation monitoring in Iitate
village in 28-28 March30μSv/h in Nagadoro-Magata

24

Dose rate map on March 29, 2011 in Iitate

Fig. 7. Location of Iitate village (left) and the contour of radiation dose rate inIntate village on March 29th, 2011 (right). Dose rates were measured in a
car moving along main roads inside village using a pocket survey meter
ALOKA PDR101. Unit: Sv/h.

Imanaka et.al Health Physics 201225

Estimates of radioactivity
release into the atmosphere
単位：PBq＝１×1015 Bq

Fukushima

Chernobyl#１～#3 Total 2.03 GWe

1GWe

NSC（April 12）
Xe-133

－

I-131

150

Cs-137

12

Sr-90－

Pu-239,240－

NISA（May 16）
11,000(97%)
160(2.5%)15(2.6%)0.14（0.03%）
0.0000064(0.0002%)

Stohl etal
(ACPD 2011)
16,700－35.8－－

Chernobyl Forum(2005)
6,500(100%)
1,760(55%)
85(30%)
10(5%)
0.03(1.5%)( ): Released fraction of the core inventory.

26

90Sr、239,240Pu contamination in Iitate

Siol contamination, Bq/m2
Cs-137

Sr-90*

Pu-239,240**＜Iitate village: NW30-40km＞＃53

1,000,0003900.01#88590,000

3000.07#165

2,200,000

7900.2＜Kyiv city：S110km Garger et al. Health Physics1996＞
Average of 6samples

25,0005,800160＊ （財）九州環境管理協会に測定を依頼．Global を含む**山本（金沢大）による測定．Pu-238 との比から、Global を差し引いた値．

Contamination ratio of Sr90 to 137 is 1/2000～1/3000,compared with Kyiv. For Pu isotopes, it is less than 1/1 million．
27

137Cs、90Sr、239,240Pu around Chernobyl

Sr-90 UNSCEAR (2000)

Cs-137UNSCEAR（2000）
Pu-234,240 Gaydar KURRI-KR-79 (2002)

Sr90 and Pu isotopes are about 10 % and 1 $of Cs137, respectively.
28

Cs137 body burden in Belarus (upper) and Russia(lower) after Chernobyl

Minenko et.al
Health Physics 2006

Zvnova et al.
Radiation Protection Dosimetry
2000
29

Recent Cs137 body burden od children incontaminated area in Belarus.
Data from Belrad.
平均体内セシウム137量、Bq/kg

検査グループ全体
1120

1200

危険グループ

1142.7

900
662.7
600

632.9

575.6
311.7
331.6
220.2

185.6
110.3

218.7
84.6

54.4
70.3

86.4

81.3

39.9

(n=46)00
3
16(n.1=42.
4)
20
03
89.
(n04=2.23)00
4(n28=1.04.
1820)
05
22(n.1=21.
6)
2006
23(n.0=71.
0)2007
22(n.0=55.
6)
2007(n=79)

74.2

172.3

18.0

2002.06.

1197.96.
27)=8(n002(n=70)
23.0

20
02.0
4.

00
185.
28)
=8(n2(n=73)
3.
2

13.0.0
1.
23

1.
200

2002

1(n=90)0228.3 219.3

247

189.6 262.4

300

28.1528.2

WBC検査日（n：人数）

30

WBC results in children of
Minami-soma city

Data from Minami-Soma city HP
31

Forecast of external dose ratechange from deposited radiocesiums1

空間線量率の相対強度

0.9

移行なしモデル

0.80.7

環境半減期13年モデル

0.60.50.4
0.30.20.1002468101214161820

経過年数

セシウムによる空間線量率変化の予測（移行なしモデルと環境半減期13年モデル）
32

SummaryThe same scale of radiological consequences as
Chernobyl occurred around Fukushima #1 NPP.

Released amounts into the atmosphere by theFukushima accident seem to be double for Xe133 and 20 – 40 % for Cs-137．

Contamination by Sr-90 and Pu-239,240 was
significantly lower than Chernobyl．

So far, internal contamination by radiocesiums
are surprisingly lower than Chernobyl.

33