institute of physics, savanoriu 231, lt-2058, vilnius, lithuania, e-mail: [email protected] ;

The LIETDOS-BIO assessment approach to Environment protection from ionizing radiation

T. Nedveckaite, D. Marciulioniene

Institute of Physics, Savanoriu 231, Lt-2058, Vilnius, Lithuania, E-mail: [email protected]; Institute of Botany, Žaliųjų ežerų 49, LT-2021 Vilnius, Lithuania, E-mail: [email protected]

Institute of Physics, Institute of Botany

Lithuania

mailto:[email protected]

Ignalina NPP with decommissioning, spent fuel storage and waste disposal problems;Maisiagala RADON type radioactive waste repository amongst others with earlier (1963-1973) military radioactive waste from Lithuania, Kaliningrad and Belarus.

EstoniaRussian

Federation

BelarusPoland

Lithuania

Latvia

INPP

KaliningradMaisiagala

repository

Ignalina NPP, Druksiai Lake – cooling pond,spent fuel storage

RSR – rain sewage release, Intake - cooling water intake, Release - cooling water release, PFoHE - purification facility of the household effluents of INPP and Visaginas, HSS – household sewerage release after biological treatment, SFSF - Spent Fuel Storage Facility.

The sampling points in Ignalina NPP

cooling pond-Druksiai Lake

The spatial pattern of activated corrosion products54Mn and 90Co in bottom sediments of Druksiai Lake.

The highest activity concentrations correspond to sampling points: 2-sewerage outflow and 4-cooling water outflow .

Other monitoring radioniclides and heavy metals:54Mn, 60Co, 137Cs, 90Sr, 210Pb, 210Po, 238U, 226Ra, 232Th

Pb, Cd, Cr-VI, Ni, Cu, Zn-II, Zn

The projected Ignalina NPP decommissioning low-level

repository sites

MAISIAGALA radioactive waste repository

Tritium in underground water in close vicinity of the repository reservoir (January-March 2007)

0 1 2 3 4 5 6 7 8 90

100

200

300

400

500

600

4000

8000

12000

16000

20000

3 H,

Bq

L-1

Gręžinio Nr.

2007.01.30 2007.02.28 2007.03.23

Borehole No.

LIETDOS and LIETDOS-BIO – a software to calculate the radiological dose for human and non-human biota due to

the presence in LITHUANIA radiation safety problems

LIETDOS –segmental atmospheric diffusion-convection model-code tested using data on I-131 released from Hanford (BIOMASS)

LIETDOS-human exposure modelused for the regulating document in Lithuania LAND 41-2001 : “Limitation of Radioactive Discharges from nuclear facilities and

Order of Issuance of Permits for Discharges”

• Nedveckaite T., Motiejunas S., Kucinskas V., Mazeika J., Filistovic V., Jusciene D., Maceika E., Morkeliunas L., Hamby D.M. Environmental releases of radioactivity and the incidence of thyroid disease at the Ignalina Nuclear Power Plant. Health Physics, Vol. 79, No. 6, 666-684 (2000)

LIETDOS-BIO modela tool for calculating radiation doses

to Freshwater and Terrestrial Biota with input file that is subsequently read by MCNPX

MCNPX code

Source(nuclide)

Ecosystem Organisms/reference organisms

Dynamic/steady-state transfer modelling

Radionuclide concentration in

medias

Internal radionuclide

concentration

Preparing MCNPX input file for DCC

calculations

External dose (rate)

Crystal Ball

Total dose (rate)

DCC calculations

Internal dose (rate) Weighting

General/site-specific parameters

LIETDOS-BIO code

• LIETDOS-BIO code is designed to be consistent with MCNPX code. MCNPX is commonly used general purpose radiation transport code that tracks all particles at all energies for internal and external exposure of any geometry organisms calculation.

• LIETDOS-BIO code is designed to be consistent with Crystal Ball software (Crystal Ball is a software for uncertainty analyses) for statistical calculation approaches.

EXPERT CONTROLLED INFORMATION This is a limited distribution unclassified documents with code and may not be given to other persons.

LIETDOS-BIO code Libraries and Data Bases:Nuclides Library - Electron, Positron, Beta, Alpha and Gamma Energy's data

(ICRP 38) Reference Organisms Library:Terrestrial and Freshwater Ecosystems

Concentration ratios (CR) – 3 Data Bases

Partitioning coefficients (Kd) Library and etc.

LIETDOS-BIO (3 CR Data Bases)• Site-specific radionuclide CR distribution-geometric mean

values : Data Bases No. 1.• Generic radionuclide CR values (FASSET, ERICA, BWG Ex

2 CR values): Data Bases No. 2.• Stable nuclide (heavy metals) CR values (ERICA, site-

specific). As demonstrate presented picture after the Chernobyl accident stable CR value may be used after few years: Data Bases No. 3.

FRESHWATER ECOSYSTEM90Sr CR for different type of Macrophytes –

site-specific valuesBased on these data statistical CR approach has been used

0 200 400 600 800 1000 1200 1400

Chara asperaChara rudis

Chara fragilisChara contraria

Chara tomentosaChara vulgaris

Nitelopsis ObtuseElodea canadensis

Potamogeton lucensMyrophyllum spicatum

Ceratophyllum demersumPotamogeton pectinatus

Stratiotes aloidesPotamogeton perfoliatus

Potamogeton natansNitella syncarpaLemna trisulca

Cladophora glomerataUtricularia vulgaris

Mean value Standard deviation

The distribution of site specific Sr-90 CR values (macrophytes) involved in DB Nr 1

0 200 400 600 800 1000 1200 1400 1600 18000.00

0.02

0.04

0.06

0.08

0.10

0.12

0.14

0.16

0.18

0.20Mean 3.72e+2Geom.Mean 2.84e+2SD 3.14e+2Geom. SD 2.08e+0Median 2.89e+2Skewness 2.48e+0Kurtosis 1.25e+1P05 3.00e+1P95 8.95e+2F

requ

ency

Concentration Ratio

Co-60 CR (FW) site-specific distribution (macrophytes): LIETDOS-BIO site-specific DB (example)

Frequency Chart

m3/kg

.000

.025

.050

.074

.099

0

495.2

990.5

1981

0.055 13.023 25.991 38.959 51.927

20 000 Trials 19 522 Displayed

Forecast: Co-60 Concentration Factor (CF) FW plant

Statsistics: Value

Trials 20000

Mean 8.61

Geometric Mean 3.87

Median 3.565

Mode ---

Standard Deviation 17.114

Variance 292.875

Skewness 7.81

Kurtosis 115.80

Coeff. of Variability 1.99

Range Minimum 0.008

Range Maximum 544.488

Range Width 544.480

Mean Std. Error 0.121

TERRESTRIAL ECOSYSTEMPlume of the Chernobyl accident formation by

meteorological conditions for instantaneous releases on dates and times (GMT) indicated

Aerial Gamma - Spectrometry Test Results. Spots Denote Areas Where the Density of Cs-137 is at least 3700

Bq/square meter (the first contour), with a Contour-spacing of 1100 Bq/m2

Soil Cs-137 activity distribution Bq/kg, 1986-1996Lithuania

Frequency Chart

.000

.006

.012

.018

.024

0

58.75

117.5

176.2

235

8.30 10.36 12.42 14.49 16.55


Forecast: Soil (Lithuania), Bq/kg

o

Statistic Value

Trials 10 000

Mean 12.4

Median 12.28

Mode ---

Standard Deviation 1.57

Variance 2.47

Skewness 0.44

Kurtosis 3.4


Range Minimum 7.28

Range Maximum 19.83

Range Width 12.56

Mean Std. Error 0.02

The distribution of site specific Cs-137 CR values

involved in DB Nr 1 (Wild boar)

Trials 10 000

Mean 2.41

Geom. Mean 2.37

Median 2.36

Mode ---

Stand. Deviation 0.46

Variance 0.21

Skewness 0.61

Kurtosis 3.72

Range Minimum 1.26

Range Maximum 4.98

Frequency Chart

.000

.006

.011

.017

.022

0

56

112

168

224

1.32 1.89 2.46 3.03 3.61


Forecast: CR wild boar

Internal Dose rate calculation

• Biota activity concentration and internal dose rate was calculated as follows:

waterd

entsebiota CСR

K

CСRC dim

biotaintinternal CDCCD

Crystal Ball statistical technique was used with 10 000 number of trials and the Latin Hypercube sampling method. An example:

Forecast: Co-60 Internal dose rate (macrophyte)

Trials 20000

Mean 2.83E-04

Geometric Mean 2.07E-04

Median 2.07E-04

Mode ---

Standard Deviation 2.63E-04

Variance 6.90E-08

Skewness 3.47

Kurtosis 28.18


Range Minimum 9.15E-06

Range Maximum 5.61E-03

Range Width 5.60E-03

Frequency Chart

mkGy/h

.000

.008

.016

.024

.032

0

160.7

321.5

482.2

643

1.69E-5 2.55E-4 4.93E-4 7.31E-4 9.69E-4


Forecast: Co-60 Internal dose rate (Dint) Plant

External dose rate calculation

• External dose rate from sediment (FW) :

• External dose rate from sediment (DW):wetsed

dryseddrysedsedwetsedsedsedext CDCCCDCCD

,

,,,,

drysedsedsedext CDCCD ,, 1,

, wetsed

drysed

An example of model for MCNPX code DCC calculation -fish (ellipsoid on sediment) in the middle of water cylinder

10 cm

R = 100 cm

5 cm

Hw

=

100

cm

Water

Sediment

Fish

Wf = 60 cm

Hf = 10; Df = 5 cm

Hc=(10 +2 l); Dc= (5 +2 l) cm

Wc = (60 + 2 l) cm

An example of model for MCNPX code external exposure DCC

calculation: fish (ellipsoid) in the middle of water cylinder

Wf = 20 cm

R = 100 cm

50 cm

Hw =

10

0 cm

10 cm

Hf = 12; Df = 4 cm

Water

Sediment

Fish

Hc=(12 +2 l); Dc= (4 +2 l) cm

Wc = (20 + 2 l) cm

An example of model for MCNPX code DCC calculation -rooted submerged hydrophytes

= 1 cmR = 100 cm

Hw

=

10

0

cm

10 cm

Water

Sediment

Plant

An example of model for MCNPX code DCC calculation -unrooted submerged hydrophytes

= 10 cm

R = 100 cm

Hw

=

10

0

cm

10 cm

h = 0.2 cm

Water

Sediment

Plant

h0 = 0.1 cm

Crystal Ball statistical technique was used with 10 000 number of trials and the Latin Hypercube sampling method. An example:

Forecast: Co-60 External dose rate (macrophyte)

Trials 20000

Mean 1.38E-02

Geometric Mean 9.72E-03

Median 9.73E-03

Mode ---

Standard Deviation 1.39E-02

Variance 1.93E-04

Skewness 4.23

Kurtosis 42.67


Range Minimum 3.57E-04

Range Maximum 3.39E-01

Range Width 3.38E-01

Mean Std. Error 9.83E-05

Frequency Chart

mkGy/h

.000

.009

.018

.027

.037

0

183

366

549

732

4.53E-4 1.28E-2 2.53E-2 3.77E-2 5.02E-2


Forecast: Co-60 External dose rate (Dext) Plant

LIETDOS-W subroutine

• Taking into account tritium activity concentrations in the Ignalina Lake water and groundwater as well as groundwater activity in the vicinity of Maisiogala repository the LIETDOS-W code was developed to predict freshwater BIOTA exposure.

• LIETDOS-W code was tested during Perch Lake scenario (EMRAS working group on Modeling of tritium transfer to biota and man).

Freshwater HTO

Biota OBT

Biota HTO

Sediment Layer HTO

LIETDOS-W subroutine

Steady-state tritium transfer modelling

LIETDOS-BIO

LIETDOS-W: HTO and OBT concentrations in clams(EMRAS TWG Pearch Lake scenario: L – LIETDOS-W data)

HTO concentrations in clams. The model predictions are shown as solid diamonds with the vertical lines representing 95% confidence intervals as estimated by themodelers. The solid horizontal line is the observation with the 95% confidence interval indicatedby the dashed lines.

OBT concentrations in clams. The model predictions are shown as solid diamonds with the vertical lines representing 95% confidence intervals as estimated by themodelers. The solid horizontal line is the observation with the 95% confidence interval indicatedby the dashed lines.

The main LIETDOS-BIO features

• As the organism for which DCC calculated is defined by user, there is possibility for optional using references as well as other organisms or criteria.

• The application of stochastic and probabilistic approach is one of possibility to improve the correctness of biota exposure predictions.

• Radiation Protection and radiological dose assessment tools are well established for humans through the ICRP and national recommendations. Up to now Environment protection from ionizing radiation in Lithuania is accepted as much as it is interconnected with human exposure.

THANK YOU FOR ATTENTION!

institute of physics, savanoriu 231, lt-2058, vilnius, lithuania, e-mail: [email protected] ;

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