Dynamics of Radio Cesium Released by Fukushima Daiichi ... presentations...3 years Cs-137 variation in RW, TF, SW, GW, RW in Ko 11 (Bq /L) 10⁻² 1.0E-04 1.0E-03 1.0E-02 1.0E-01 1.0E+00

Dynamics of Radio Cesium Released by Fukushima Daiichi NPP Accident in Hydrological Cycle of Groundwater,

Surface Water and Spring Water in the Headwater Catchments

Maki TSUJIMURA Yuichi ONDA, Sho IWAGAMI, Yutaka ABE, Manami HADA,

Pun ISHWAR, Masataka NISHINO, Ryohei KONUMA

University of Tsukuba

1

This work was carried out as a commissioned study from the JAEA, as a part of

FY2012 project entitled “The establishment of grasp method of long-term

effects caused by radioactive materials from the Fukushima Dai-ichi Nuclear

Power Plant accident”, financially supported by the Ministry of Education,

Culture, Sports, Science and Technology, the Japanese Government.

137Cs deposition map obtained by aircraft monitoring

2

Fukushima

Daiichi NPP

Study area:

Yamakiya district

10 km

Targets

• To monitor dissolved radio cesium concentration in the rainfall, soil water, groundwater, and stream water in headwater catchments covered by grass, forest and crop located at 30 km west-north from Fukushima NPP.

• To understand hydrological processes during rainfall-runoff events regarding increase of Cs concentration in stream.

3

Behavior of nuclear isotopes with hydrological cycle

地下水観測井戸ｘ2セット

土壌水3深度x6地点

三角堰による河川流量観測（左）とオートサンプラーによる河川水自動採水（右）

Sampling of GW using piezometers

Soil water sampling

Soil water Shallow GW Deep GW Runoff

Sampling of discharge water

Paddy field

Cultivated area

Forest

5

Grassland (Iboishi yama/ Recharge area)

Cultivated land (Ishidaira yama)

Farmland (Koutaishi yama/ Discharge area)

Kawamata Cop. (Mizusakai river)

FDNPP

Ib-watershed

Ko-watershed

Forest site

Ib

Ko

Ib watershed-

Grassland-Forest

Ko watershed- Forest

dominant

(10% farmland)

Sampling of soil water Young Forest

Ko watershed Old Forest

Ib watershed

7

Suction lysimeter Soil moisture sensors 0.1 m, 0.3 m, 0.5m

0.1 m, 0.2 m, 0.3 m

0.1 m, 0.3 m, 0.5m

Boreholes installation

8

30 m 15 m 5 m

0 m

10 m

20 m

30 m

20 m 6 m 3 m

Ib site Ko site

Len

gth

of

the

Bo

reh

ole

(m

)

Aaverage

Water level

Scr

een Boreholes at Ib watershed

Boreholes at Ko watershed

0

20

40

60

80

10010

100

1000

10000

降雨量

(mm

/h)

比流量

(l/s・km

²)

10

100

1000

10000

Rain

fall (mm

/h) Sp

ecif

ic d

isch

arge

(L

/s・

km²)

0

20

40

80

100

60

2011 2012

Ko watershed (Discharge area) Ib watershed (Recharge area)

0.1

1

10

100

1000

0 95 185 275

10

100

1000

0.1

1

95 185 275

Dis

char

ge

(mm

/day

) Ko watershed Ib watershed

(Days)

Rainfall

Runoff Characteristics

9

3 years Cs-137 variation in RW, TF, SW, GW, RW in Ib

10

Cs

con

cen

trat

ion

(B

q/L

)

10⁻²

1.0E-04

1.0E-03

1.0E-02

1.0E-01

1.0E+00

1.0E+01

1.0E+02

1.0E+03

6/12 8/1 9/20 11/9 12/29 2/17 4/7 5/27 7/16 9/4 10/2412/13 2/1 3/23 5/12 7/1

Cs 濃度

(Bq

/L)

10³

10

10⁻¹

10⁻²

10⁻³

10⁻⁴

10

6/12 9/20 12/29 4/7 7/16 10/24 2/1 5/12 2011 2012 2013

Rain, Throughfall, Stream

0.0001

0.0010

0.0100

0.1000

1.0000

10.0000

6/12 8/1 9/20 11/9 12/29 2/17 4/7 5/27 7/16 9/4 10/2412/13 2/1 3/23 5/12 7/1

Cs 濃度

(Bq

/L)

10

1

10⁻²

10⁻³

10⁻⁴

10⁻⁵

G30(m)_Cs137 G15(m)_Cs137 G5(m)_Cs137

G5/G15(m)_Cs137 ND G5(m)_Cs137 ND

G15(m)_Cs137 ND Groundwater

0.0001

0.0010

0.0100

0.1000

1.0000

10.0000

6/12 8/1 9/20 11/9 12/29 2/17 4/7 5/27 7/16 9/4 10/2412/13 2/1 3/23 5/12 7/1

Cs 濃度

(Bq

/L)

1

10⁻³

10⁻⁴

10⁻⁵

SW10(cm)_Cs137 SW30(cm)_Cs137

SW50(cm)_Cs137

SW10/SW30/SW50(cm)_Cs137 ND

Soil Water

1

10²

Cs137 Event1-Cs137 Event2-Cs137 Event3-Cs137

TF_Cs137 RF_Cs137 RF_Cs137 ND

3 years Cs-137 variation in RW, TF, SW, GW, RW in Ko

11

Cs

con

cen

trat

ion

(B

q/L

) 10⁻²

1.0E-04

1.0E-03

1.0E-02

1.0E-01

1.0E+00

1.0E+01

1.0E+02

1.0E+03

6/12 8/1 9/20 11/9 12/29 2/17 4/7 5/27 7/16 9/4 10/2412/13 2/1 3/23 5/12 7/1

Cs 濃度

(Bq

/L)

6/12 9/20 12/29 4/7 7/16 10/24 2/1 5/12 2011 2012 2013

Rain, Throughfall, Stream

0.0001

0.0010

0.0100

0.1000

1.0000

10.0000

6/12 8/1 9/20 11/9 12/29 2/17 4/7 5/27 7/16 9/4 10/2412/13 2/1 3/23 5/12 7/1

Cs 濃度

(Bq

/L)

10

1

10⁻²

10⁻³

10⁻⁴

10⁻⁵

Groundwater

G20(m)_Cs137 G6(m)_Cs137 G3(m)_Cs137

G3/G6(m)_Cs137 ND G3(m)_Cs137 ND

G6(m)_Cs137 ND


TF_Cs137 RF_Cs137 RF_Cs137 ND

10³

10

10⁻¹

10⁻³

10⁻⁴

1

10²

10⁻⁵ 0.0001

0.0010

0.0100

0.1000

1.0000

10.0000

6/12 8/1 9/20 11/9 12/29 2/17 4/7 5/27 7/16 9/4 10/2412/13 2/1 3/23 5/12 7/1

Cs 濃度

(Bq

/L)

10

1

10⁻²

10⁻³

10⁻⁴

Soil Water

SW10(cm)_Cs137 SW20(cm)_Cs137 SW30(cm)_Cs137

SW10/SW20/SW30(cm)_Cs137 ND

SW10/SW30(cm)_Cs137 ND SW10(cm)_Cs137 ND

SW30(cm)_Cs137 ND

3H concentration in 2011

12

Stream water Spring water groundwater

5m 15m 30m 3m 6m 20m

Ib (21 Jun) Ko (29 Jul) Ib

St.w St.w Sp.w St.w

Precipitation

Tokyo & Tsukuba

21 May

1 Jun

21 May

Spring water Groundwater Stream water

1.0E-04

1.0E-02

1.0E+00

1.0E+02

1.0E+04

1.0E+06

6/12 8/1 9/20 11/9 12/29 2/17 4/7 5/27 7/16 9/4 10/2412/13 2/1 3/23 5/12 7/1

Cs 濃度

(Bq

/L)

1.0E-04

1.0E-02

1.0E+00

1.0E+02

1.0E+04

1.0E+06

6/12 8/1 9/20 11/9 12/29 2/17 4/7 5/27 7/16 9/4 10/2412/13 2/1 3/23 5/12 7/1

Cs 濃度

(Bq

/L)

1.0E+00

1.0E+02

1.0E+04

1.0E+06

6/12 8/1 9/20 11/9 12/29 2/17 4/7 5/27 7/16 9/4 10/2412/13 2/1 3/23 5/12 7/1

Cs 濃度

(Bq

/L)

1.0E+00

1.0E+02

1.0E+04

1.0E+06

6/12 8/1 9/20 11/9 12/29 2/17 4/7 5/27 7/16 9/4 10/2412/13 2/1 3/23 5/12 7/1

Cs 濃度

(Bq

/L)

1.0E+00

1.0E+02

1.0E+04

1.0E+06

6/12 8/1 9/20 11/9 12/29 2/17 4/7 5/27 7/16 9/4 10/2412/13 2/1 3/23 5/12 7/1

Cs 濃度

(Bq

/L)

1.0E+00

1.0E+02

1.0E+04

1.0E+06

6/12 8/1 9/20 11/9 12/29 2/17 4/7 5/27 7/16 9/4 10/2412/13 2/1 3/23 5/12 7/1

Cs 濃度

(Bq

/L)

0

10

20

30

40

501

10

100

1,000

6/12 8/1 9/20 11/9 12/29 2/17 4/7 5/27 7/16 9/4 10/2412/13 2/1 3/23 5/12 7/1

雨量

(mm

/h)流

量(L

/s)

0

10

20

30

40

501

10

100

1,000

6/12 8/1 9/20 11/9 12/29 2/17 4/7 5/27 7/16 9/4 10/2412/13 2/1 3/23 5/12 7/1

雨量

(mm

/h)流

量(L

/s)

Cs 137 variation in river, SS, organic material

10

10²

10³

1

0

10

20

30

40

50

Dis

char

ge (

L/s)

Rain

fall (mm

/h)

Ib Ko

10

10²

10³

1

Dis

char

ge (

L/s)

0

10

20

30

40

50

Rain

fall (mm

/h)

10⁶

10²

10⁻²

10⁻⁴

Cs

con

cen

trat

ion

(B

q/L

)

Cs

con

cen

trat

ion

(B

q/L

)

6/12 9/20 12/29 4/7 7/16 10/24 2/1 5/12 2011 2012 2013

6/12 9/20 12/29 4/7 7/16 10/24 2/1 5/12 2011 2012 2013

Stream (Dissolved phase)

SS

Organic matter

SS

Organic matter

13

Rainfall Discharge Rainfall Discharge

1

10⁴ Cs137 Event1-Cs137 Event2-Cs137 Event3-Cs137

10⁶

10²

1

10⁴

10⁶

10²

10⁻²

10⁻⁴

1

10⁴

10⁶

10²

1

10⁴

10⁶

10²

1

10⁴

10⁶

10²

1

10⁴


Stream (Dissolved phase)

Cs-137 in stream

14

Ib watershed Ko watershed

Cs-137 in Soil Water & Groundwater (Ib watershed)

15

Soil water Groundwater

0.1 m depth 5 m depth



Cs-137 in Soil Water & Groundwater (Ko watershed)

16

Soil water Groundwater




Cs-137 profile of soil water at Ib in July 2011

17

Bq/ Kg Bq/ Kg

Dep

ths

Dep

ths

Dep

ths

Bq/ Kg

Cs-137 distribution at depths in soil taken on 1) Jul 2011, 2)

Jan 2012, 3) Aug 2012, 4) Dec 2012 (Takahashi, Onda, 2014)

9th Jul

15th Jul

23rd Jul

Cs-137 profile of soil water at Ko in Jul & Aug 2011

Bq/ Kg

Dep

ths

18

Bq/ Kg

N/A

N/A

N/A

N/A

Dep

ths

Bq/Kg

9th Jul

16th Jul

16th Aug

Cs-137 profile of soil water at young forest

19

Bq/ Kg

Bq/ Kg

Dep

ths

Dep

ths

N/A

Dep

ths

N/A

N/A

Bq/Kg

16th Jul 23rd Jul

16th Aug

Long Trend of Solute Conc.

20


Runoff/ Solution Response in an Event

21


Runoff/ Cs Response in an Event

22


End Members Mixing Analysis

23


Hydrological stream water sources evaluation by mass balance model

Runoff Components at Ib

24

Runoff Components at Ko

25

rainfall Cs134 0～0.41 (Bq/L) Cs137 0～0.22 (Bq/L)

snowfall Cs134 0～2.42 (Bq/L) Cs137 0～2.67 (Bq/L)

Stream water Cs134 0～0.46 (Bq/L) Cs137 0～0.58 (Bq/L)

Rainfall Aug～Dec.2011, Apr～Jun.2012 Snowfall Jan～Mar.2012 Stream water Jun.2011～Jun.2012 Ground water Sep.2011～Oct.2012

Spring water Cs134 0～0.34 (Bq/L) Cs137 0～0.36 (Bq/L)

3m Cs134 0～3.6×10-3 (Bq/L) Cs137 0～4.4×10-3 (Bq/L)

6m Cs134 0～3.2×10-3 (Bq/L) Cs137 0～4.2×10-3 (Bq/L)

20m Cs134 8.9×10-4 ～ 3.2×10-2 (Bq/L) Cs137 1.5×10-3 ～ 3.9×10-2 (Bq/L)

(near the point) Kawamori, 2012

: Residence time by CFC-12

21(years)

23(years)

27(years)

Summary of Ib watershed

rainfall Cs134 0～0.28 (Bq/L) Cs137 0～0.93 (Bq/L)

3m Cs134 0～1.1×10-3 (Bq/L) Cs137 0～2.8×10-3 (Bq/L)

6m Cs134 0～1.0×10-3 (Bq/L) Cs137 0～1.2×10-3 (Bq/L)

20m Cs134 6.9×10-4 ～1.1×10-2 (Bq/L) Cs137 8.6×10-4 ～1.3×10-2 (Bq/L)

Stream water Cs134 0～0.24 (Bq/L) Cs137 0～0.31 (Bq/L)

snowfall Cs134 0～0.89 (Bq/L) Cs137 0～2.42 (Bq/L)

Rainfall Aug～Dec.2011, Apr～Jun.2012 Snowfall Jan～Mar.2012 Stream water Jun.2011～Jun.2012 Ground water Sep.2011～Oct.2012

(near the point) Kawamori, 2012

25(years)

26(years)

28(years)

: Residence time by CFC-12

Summary of Ko watershed

Summary • Cs-137 conc. in stream water ranging from 0.12

to 1.18 Bq/L in 2011, decreased to below 0.1 Bq/L after 2012. Cs in groundwater and soil water ranged from 0.001 to 0.039 Bq/L, from 0.12 to 2.48 Bq/L, respectively in 2011, and recently no detected.

• Cs conc. in stream water during rainfall events ranging from 0.07 to 0.52 Bq/L.

• End-member mixing analysis (EMMA) suggesting GW contribution to storm runoff dominant ranging from 64.2 to 88.2%, but cannot represent Cs conc dynamcs.

• Source of Cs increase in runoff seems to be litter?

28

Documents

Dynamics of Radio Cesium Released by Fukushima Daiichi ... presentations...3 years Cs-137 variation in RW, TF, SW, GW, RW in Ko 11 (Bq /L) 10⁻² 1.0E-04 1.0E-03 1.0E-02 1.0E-01 1.0E+00