Transcript The development of composition and technology of amendment

From Chernobyl to
Fukushima: introduction
Conveners of GI1.4 session
M. Yamauchi (Swedish Institute of Space Physics, Sweden)
Oleg Voitsekhovych (Ukrainian Hydrometeorological Institute, Ukraine)
Elena Korobova (Vernadsky Institute of Geochemistry and Analytical
Chemistry, Russian Federation)
Michio Aoyama (Meteorological Research Institute, Japan)
Kazuyuki Kita (Ibaraki University, Japan)
Andreas Stohl (Norwegian Institute for Air Research, Norway)
Gerhard Wotawa (Central Inst. Meteorology and Geodynamics, Austria)
Naohiro Yoshida (Tokyo Institute of Technology, Japan)
From Chernobyl to Fukushima: introduction
Cesium Deposition on Europe, 1986
by GRID-Arendal (©European Commission, Joint
Research Center, Environment Institute, Institute of
Global Climate and Ecology; Roshydromet;
Minchernobyl; Belhydromet)
©Soviet Authorities
From Chernobyl to Fukushima: introduction
• Environment / Geoscience aspect
Without understanding contamination science,
we cannot estimate or protect human exposure
• Multi-disciplinary aspect
- Dynamics / Physics / Chemistry / Biology
- Local / Regional / Global
- Urban / Field / Forest / Water / Ocean
• Multiple-route effects of radionuclide
- External & internal dose
- Physical & biological/environmental decay
- Hardness of radiation (mainly gamma)
Many sciences are involved
Fluid Dynamics and Transport
Physics
Chemical
property (ionized,
exited, bind etc)
Biochemical
transfer and
concentration
How easy to
resolve in water
(Shestopalov et al., 2003)
(c)
(b)
(a)
example: Three types
of fallout
 Different science chemistry &
physics involve for the further
movement of the radionuclides
(a)
(b)
(c)
Our GI1.4 session covers:
1 Radionuclide release and deposition (contamination)
Aerosol physics-chemistry
Atmospheric transport
Surface contamination (fallout)
2 Land environment (contamination & countermeasures)
(Urban), Agriculture, Forest (=Soil-system & Ecosystem)
3 Aquatic environment (contamination & countermeasures)
ocean
hydrology (river, lake, ground water)
hydrology-soil system
4 Future tasks (research & technology)
monitoring & soil experiment tasks
remote sensing & unmanned vehicle technology
health risk modeling (e.g., GIS modeling)
risk analyses in general
Comparison Fukushima – Chernobyl
(same scale)
Fukushima compared to Chernobyl:
- comparable Cs-deposition levels but over smaller area
- no substantial Sr, Am, Pu deposition via atmospheric releases
- however, much larger releases to the sea
7
Speciation and similarities of the impacts
Features
Chernobyl
Fukushima
Atmospheric release
137Cs
90Sr
239-240Pu
IAEA, 2006
NISA Report, 2011
15
0,14
n/a
Atmospheric
deposition
Fuel particles, volatile and nonvolatile elements
Volatile elements only
Deposition areas
Mainly central Europe: Terrestrial
ecosystems,
catchments of the Dnieper and
Danube River basin,
forest and agriculture areas,
Black Sea and Baltic Sea.
* Huge transboundary effect
Pacific coast of Japan:
Complex landscape,
forest, agricultural area,
high density of population,
ocean ecosystem.
* Transboundary effects
negligible
Prevailing pathways
of exposure
External exposure,
consumption of milk and meat,
vegetables
External exposure,
consumption of milk and meat,
vegetables, seafood
47
85
0,03
In both cases the water pathways are not prevailing in human dose
exposure, however its role are significant in some cases of specific water
use such as irrigation, water supply, fishery and seafood production and also
can create inadequate risk perception phenomena
(1)
(3)
(2)
(6)
(4)
(5)
Calculated plume formation according
to meteorological conditions for
instantaneous releases on the
following dates and times (GMT):
(1) 26 April, 00:00; (2) 27 April, 00:00; (3)
27 April, 12:00; (4) 29 April, 00:00; (5) 2
May, 00:00; and (6) 4 May, 12:00
(Borsilov and Klepikova 1993).
Radioactive contamination of the
catchments after Chernobyl and
aquatic environment, as versus of
fallout formation date, its physical
and chemical forms and also
speciation of the the landscapes at
the deposited river watersheds
137Cs
activity concentration in different
rivers per unit of deposition (Smith, 2004)
Speciation of soils and radionuclides behavior
Specificity of soils in Japan
Andosols (soils developed on
volcanic ash) – 16 % of soils

Paddy soils (waterlogged
soils): most rice = paddy rice

Limited knowledge on
radiocesium behavior in andosols
and waterlogged paddy soils:
increased availability expected
Andosols: low in clay, high in
organic matter
Paddy soils: under reduced
conditions generation of NH4+
which increases Cs mobility
and bioavailability

In Chernobyl case fallout was
covered wide variability type of
soils in BE,RU,UA, Europe
Mobility and bioavailability of
radionuclides are determined
by ratio of radionuclide
chemical forms in fallout and
site-specific environmental
characteristics determining
rates of leaching,
fixation/remobilization as well
as sorption-desorption of
mobile fraction (its solid-liquid
distribution).
Radionuclide mobile forms in deposition.
Fukushima - ?
137Cs
90Sr
Chernobyl origin
Chernobyl origin
30-km zone
Bryansk region
Cumbria, UK
(Hilton, 1992)
- 20-30 %
- 40-60 %
- 85 %
Nuclear Tests
>80 %
30-km zone
- 10-15 %
Kyshtym
- 80-90 %
Nuclear Tests
>90 %
11
Main messages from Chernobyl soil-water studies

Information on radionuclide deposition levels
alone is not enough to accurately predict future
and to assess human dose.
Data on speciation in fallout, rates of
transformation processes and site-specific
environmental characteristics determining these
rates are needed.

Information on radionuclide chemical forms,
their transformation in other words mobility and
bioavailability should be taken into account
when rehabilitation and decontamination
strategies are developed on local or regional
12
scale.
Prof. Y.Onda
Experiments on runoff plots
•
Experimental studies of the wash-off
process (liquid and particulate phase
erosion from the contaminated lands
can bring important knowledge on
mathematical
models
parameterization to be applied for
radionuclide runoff prediction after
snowmelt and rains.
•
Experience gained after Chernobyl
has to be utilized in Fucushima
affected areas as well as prior results
of the study radionuclides wash-off by
rainfall and snowmelt surface runoff.
•
These studies were conducted in
Ukraine the contaminated territories
on the runoff plots of 1 m2 to 1000 m2.
•
Currently similar studies carrying out
in
Japan
aiming
experimental
assessment
of
erosion
and
radionuclide
runoff
from
contaminated paddy and agricultural
lands
Natural erosion study in Fukushima
Artificial rain simulation studies in Ukraine
Radionuclides in Rivers at the
Chernobyl affected zone
Annual averaged 137Cs in the Dnieper River
Cs, Bq.L -1
0,9
137
1,2
0,3
Ratio of 90Sr and 137Cs in soluble forms in Pripyat
River near Chernobyl
Uzh
Irpen
Teterev
0,6
0
0
5
10
15
Time, yr
1012 Bq Radionuclide inlet to the Kiev reservoir. Pripyat River
The 137Cs concentration
in river water has been
shown to be directly
proportional
to
the
relative fraction of its
exchangeable form in the
surface soil layer.
The
monitoring data
allowed
to
validate
mathematical models

Sedimentation is a key factor of 137Cs removal from the
water column to the bottom sediments
Since 1991 to 2009
as result of several
high floods the most
of Cs-137 in bottom
sediment has been
removed with the
sediment particles
from the upper part
deposited area to the
down part sector of
the Kiev reservoir
Upper part of Kiev Reservoir
1998
Low part of Kiev Reservoir
137Cs
1991-93
1994
1994
Kiev Reservoir
Data of UHMI
2009
137Cs-137
in the Black Sea
0
0
137
200
400
10
137
Cs, TBq
600
Cs, Bq m-3 20
800
1000
30
0
TOTAL
INVENTORY
(0-200m layer) 1173+/-181 TBq
50
100
Depth, m
150
200
137
Cs activity, Bq/kg
0
500
1000
1500
After Chernobyl, the 137Cs inventory in the 050 m layer increased by a factor of 6-10 and
the total 137Cs inventory in the whole BS
basin increased by a factor of at least 2
(pre-Chernobyl value of 1.40.3 PBq after
bomb-testing fallout).

137Cs
2000
0.30-0.50
1986 (89)
Slice, cm
1.00-1.20
1.40-1.60
1.80-2.00
2.25-2.50
2.75-3.00
1963 (66)
Stations:
- BS98-16
- BS2K-37

0-0.15
0.70-0.90
C(z)=C0+a/(1+exp(-(z-z0)/b))
R = 0.91 St. Error = 2.61
input from the Danube and the Dnieper
rivers (0.05 PBq in the period 1986-2000)
was insignificant in comparison with the
short-term atmospheric fallout
Inadequate Radiation Risk Perception by Public was a key
reason in WATER PROTECTION ACTION PLAN implementing
During initial period after the Chernobyl
Accident the number of expensive
actions to reduce secondary
contamination of the rivers and
groundwater have been applied.
Dose realization (%) during a 70 years for
children born in 1986
For 1-st year about 47 %
For 10 years about 80%
Years
Most of the actions were extremely
expensive and ineffective.
From I. Los, O. Voitsekhovych, 2001
Actual dose
Public perception about
Food product, milk
water
external
inhalation
In spite of doses were estimated
to be very low, there was an
inadequate perception of the
real risks by Public using
water from contaminated
aquatic systems.
This factor made reasonable to
justify some set of limited
water remediation actions to
reduce Public stressing and
prevent further long term
surface water contamination of
the Pripyat
extra slides for questions
From Chernobyl to Fukushima: introduction
(IAEA, 2006)
From Chernobyl to Fukushima: introduction
137Cs
contamination (Kashparov et al., 2003)
From Chernobyl to Fukushima: introduction
From Chernobyl to Fukushima: introduction
(Shaw et al., 2002)
From Chernobyl to Fukushima: introduction
(IAEA, 2006)
The aquatic ecosystem radioactive contamination story,
natural attenuation process and assessment for
effectiveness of the water protection
Y.Onishi, O.Voitsekhovych,
M.Zheleznyak
Chernobyl What Have we learned.
The Successes and Failures to
Mitigate Water Contamination
over 20 years.
Springer. 2007
http://www.springer.com/environment/book/978-14020-5348-1