1. Centre for Ecology & Hydrology – Lancaster 27 th – 29 th June 2012

2.  Give an overview of what may impact on assessment results using the available approaches  In part based on things we know are being done  Consider chronology of development, misuse of default values, double accounting, screening tier application  Not considering dispersion modelling and sampling strategies www.ceh.ac.uk/PROTECT

3.  Environmental Radiological assessment approaches have developed rapidly over the last 12 y  A number of approaches have been made freely available  Some of these have been superseded  But they are still available & are being used www.ceh.ac.uk/PROTECT

4.  UK  Environment Agency R&D128 - 2001  Spreadsheet model for limited number of radionuclides  Comparatively limited review to derive CR values  Dosimetry methods similar to later approaches  Environment Agency Sp1a – 2003  Supports R&D128 including derivation of complete CR data sets using a ‘guidance approach’ (can be extremely conservative) www.ceh.ac.uk/PROTECT

5.  Europe  FASSET (EC) 2001-2004  Establish a framework for radiological environmental protection from source characterisation – interpretation, including:  Tabulated CR and DCC values for:  radionuclides of 20 elements  circa 30 reference organism in 7 ecosystems  Developed the on-line FASSET Radiation Effects Database www.ceh.ac.uk/PROTECT

6.  Europe  EPIC (EC) 2000-2003  Establish a framework for radiological environmental protection for the Arctic  Ran concurrent to FASSET and shared CR database  Although presented differently and for only 12 radionuclides  DCCs derived by a different method  Allowed participation of Russian institutes leading to EPIC effects database www.ceh.ac.uk/PROTECT

7.  Europe  ERICA (EC) 2004-2007  Developed the CR and effects (FREDERICA) databases from FASSET & EPIC  Developed FASSET dosimetry methodology  Adapted ‘guidance’ for selecting missing CRs from EA SP1a  Output - the ERICA Tool implementing the ERICA Integrated Approach  More generic ecosystem types (because of lack of data) than FASSET and adapted reference organism list (to encapsulate European protect species & remove some unjustified sub-categories)  Derived 10 µGy/h screening dose rate (by SSD)  Being maintained and updated www.ceh.ac.uk/PROTECT

8.  Europe  ERICA (EC) 2004-2007  Developed the CR and effects (FREDERICA) databases from FASSET & EPIC  Developed FASSET dosimetry methodology  Adapted ‘guidance’ for selecting missing CRs from EA SP1a  Output - the ERICA Tool implementing the ERICA integrated approach  More generic ecosystem types (because of lack of data) than FASSET and adapted reference organism list (to encapsulate European protect species & remove some unjustified sub-categories)  Being maintained and updated www.ceh.ac.uk/PROTECT ERICA supersedes both FASSET and EPIC outputs & EA state intention to move to ERICA (parameters) rather than develop R&D128 EC PROTECT supported the 10µGy/h screening dose rate – using additional data and improved data selection

9.  International  IAEA (2009-)  Developing wildlife transfer parameter handbook and associated on-line database  Database will be maintained and updates released annually www.ceh.ac.uk/PROTECT

10. ERICA New & review data EA R&D128 EPIC FASSET IAEA 422 Wildlife TRS ICRP 114 Canadian U-mine industry COG monitoring data Russian language literature SKB reports Japanese estuaries Australian data Data from new studies Post ERICA literature review........ and more

11.  International  IAEA (2009-)  Developing wildlife transfer parameter handbook and associated on-line database  Database will be maintained and updates released annually  ICRP Committee 5 (2005-)  Developing a framework (ICRP-108)  Currently provided tabulated DCC values (using ERICA methodology) and summarised effects information  Report presenting CR values for RAPs now available (ICRP-114) www.ceh.ac.uk/PROTECT Will be used to help update the ERICA Tool CR values (and recalculate EMCLs)....

12.  USA  USDOE Graded Approach (2002)  Initially supported by BCG-Calculator spreadsheet model. Still available – but replaced by:  RESRAD-BIOTA  Limited and conservative CR values for generic organisms  RESRAD-BIOTA v1.5 (2009) includes values from the ERICA CR database in supporting documentation for application in uncertainty analysis www.ceh.ac.uk/PROTECT

13.  Use out of date approaches unless you can justify why they have been used, e.g.:  OK to use R&D128 for noble gases  Not OK to use FASSET CR values because they offer more ‘refined’ reference organism list/ecosystem range.... but do be aware that this is an evolving area www.ceh.ac.uk/PROTECT

14.  To serve the purpose for which they were intended RESRAD-BIOTA, R&D128(SP1a) and the ERICA Tool give a complete list of radionuclide-organism transfer parameters.  ERICA Tool and R&D128 missing values derived using ‘guidance’ approaches. These should not be blindly used in higher tier assessments nor should they be picked out for use in other models/recommendations without being clearly identified as such  RESRAD-BIOTA Biv (=CR) values very generic and conservative www.ceh.ac.uk/PROTECT

15.  ERICA and R&D128 both clearly identify values which have been derived via guidance approach rather than data  But have been taken as ‘values’ www.ceh.ac.uk/PROTECT

16.  Some scope for ‘double accounting’ associated with daughter product half-life cut-offs  e.g. R&D128 includes all 234 Th and 234 U in DCCs for 238 U  Entering both 234 Th and 238 U activity concentrations would over estimate dose rates  RESRAD-BIOTA and ERICA both offer the user the opportunity to do similar www.ceh.ac.uk/PROTECT

17.  Some scope for ‘double accounting’ associated with daughter product half-life cut-offs  e.g. R&D128 includes all 234 Th and 234 U in DCCs for 238 U  Entering both 234 Th and 238 U activity concentrations would over estimate dose rates  RESRAD-BIOTA and ERICA both offer the user the opportunity to do similar www.ceh.ac.uk/PROTECT Understand what daughters are/are not included in default DCCs especially important for assessments of natural radionuclides

19.  Aim - to enable sites of negligible concern to be identified and removed from need for further assessment – with a high degree of confidence  Envisaged that most sites will only need this level of assessment [i.e. ‘be screened out’] www.ceh.ac.uk/PROTECT

20.  Input media concentrations compared to predefined concentrations = media concentration giving rise to screening dose rate  ERICA: ‘environmental media concentration limits’ EMCLs  RESRAD-BIOTA: ‘biota concentration guidelines’ BCGs

21. Estimated assuming:  Habitat assumption to maximise exposure  Probability distributions associated with the default CR and K d databases were used to determine 5th percentile EMCL  No conservatism applied to dosimetry  For aquatic ecosystems EMCL for water includes consideration of external dose from sediment and that for sediment includes external dose from water and biota-water transfer

22. Estimated assuming:  Infinitely large (internal) and small (external) geometries for dose calculations  Daughter T 1/2 ’s up to 100 y included  All terrestrial organisms 100% in soil; aquatic 100% water-sediment interface  ‘Maximum’ CR values or 95th percentile CR values predicted using a kinetic-allometric approach

23. www.ceh.ac.uk/PROTECT  Run RESRAD-BIOTA, ERICA Tool and EA R&D128 against 10 µGy/h screening dose rate  Data suitable for application in screening tier assessment report – maximum media activity concentrations for  Four freshwater  Three terrestrial scenarios  Taken from SENES-WNA report 2007

24. Activity concentration (Bq l -1 or Bq kg -1 ) FW1FW2FW3FW4 NuclideWaterSedimentWaterSedimentWater Sediment 3H3H5.60x10 4 2.78x10 3 14 C 4.81x10 -1 60 Co2.52x10 -2 1.59x10 2 8.51x10 -2 90 Sr1.60x10 -1 6.00x10 2 7.50x10 -3 9.60x10 -1 2.74x10 -1 106 Ru2.602.32x10 3 8.14x10 -1 131 I1.10x10 -1 1.10 1.44x10 -1 137 Cs8.80x10 -2 2.08x10 3 8.50x10 -3 8.504.44x10 -3 210 Po5.00x10 -2 3.70x10 2 3.70x10 -2 1.51x10 3 234 U ** 8.00x10 -2 2.05x10 1 2.001.00x10 2 3.05x10 -1 2.15x10 4 234 Th *** 8.00x10 -2 1.00x10 2 1.809.10x10 1 3.05x10 -1 2.15x10 4 238 U8.00x10 -2 1.00x10 2 1.809.10x10 1 3.05x10 -1 2.15x10 4 239 Pu9.50x10 -5 5.06x10 1 241 Am5.00x10 -3 5.00x10 1

25. EA R&D128 + RESRAD-BIOTAERICA Tool Radionuclide Most exposed groupRQ Most exposed groupRQ Most exposed groupRQ FW3 3H3HAll organisms2.7x10 -3 Riparian animal1.1x10 -3 Phytoplankton8.1x10 -3 14 CDuck1.0x10 -2 Riparian animal8.5x10 -2 Bird3.1x10 -2 60 CoBacteria2.6x10 -2 Aquatic animal3.1x10 -2 Insect larvae4.6 90 SrDuck2.1x10 -2 Riparian animal1.1x10 -1 Insect larvae7.8x10 -2 106 RuDuck6.2x10 -1 n/iInsect larvae6.4 131 IDuck1.2x10 -3 Riparian animal1.2x10 -3 Phytoplankton6.9x10 -3 137 CsDuck8.9x10 -4 Riparian animal1.1x10 -2 Insect larvae8.7x10 -2 SUM6.9x10 -1 2.4x10 -1 1.1x10 1 Co-60 (& Ru-106) – ERICA Tool k d values >> than values in other two models

26. EA R&D128RESRAD-BIOTAERICA Tool Radionuclide Most exposed groupRQ Most exposed groupRQ Most exposed groupRQ FW4 210 Po Large benthic crustacean, Small benthic crustacean, Benthic mollusc3.5x10 2 Aquatic animal1.1x10 -1 Bivalve mollusc1.4x10 1 234 Un/aAquatic animal1.6Vascular plant6.7x10 4 234 Thn/a Insect larvae3.3x10 2 238 UDuck2.9x10 4 Aquatic animal2.0Vascular plant5.7x10 4 SUM2.9x10 4 4.61.3x10 5 U-238 – ERICA Tool and EA R&D128 RQ estimated from input sediment; kd value used estimates much higher water activity concentration than observed; RESRAD- BIOTA uses water and sediment inputs separately

27. NuclideT1T2T3 Soil (Bq kg -1 )Air (Bq m -3 )Soil (Bq kg -1 )Groundwater (Bq m -3 ) Soil (Bq kg -1 ) 3H3H6.59x10 2 4.81x10 7 7.00x10 9 14 C4.81x10 -1 2.16x10 3 2.37x10 6 60 Co4.52x10 2 90 Sr1.85 137 Cs1.80x10 2 2.85x10 1 234 U ** 6.09x10 4 6.08 234 Th *** 9.40x10 3 6.08 238 U9.40x10 3 6.08 239 Pu7.00

28. T2EA R&D128RESRAD-BIOTAERICA Tool 3H3HFungi1.4x10 -1 Terrestrial animal 3.3x10 1 Detritivorous invertebrate 2.5x10 -1 14 CSeed6.3x10 -3 Terrestrial animal 6.0x10 -2 Mammal (Deer)5.8x10 -3 60 CoFungi5.3x10 -2 Terrestrial plant8.0x10 -2 Mammal (Rat)6.1x10 -2 90 SrCarnivorous mammal 5.9x10 -4 Terrestrial animal 8.9x10 -3 Reptile4.9x10 -3 137 CsCarnivorous mammal 5.7x10 -3 Terrestrial animal 1.5x10 -1 Mammal (Deer)9.1x10 -3 SUM2.0x10 -1 3.4x10 1 3.3x10 -1 H-3 – Difference in input options RESRAD-BIOTA = soil (+ groundwater) other two models = air. Soil concentrations in excess of what would be anticipated from air.

29. EA R&D128RESRAD-BIOTAERICA Tool Radionuclide Limiting organismRQ Limiting organismRQ Limiting organismRQ T1 137 CsCarnivorous mammal 3.6x10 -2 Terrestrial animal 9.4x10 -1 Mammal (Deer)5.8x10 -2 234 Un/aTerrestrial animal 1.3Lichen & bryophytes 3.7x10 1 234 Thn/a Grasses & Herbs5.9x10 -2 238 UFungi1.4x10 2 Terrestrial plant6.5x10 -1 Lichen & bryophytes 6.2 239 PuFungi5.8x10 -2 Terrestrial plant6.0x10 -4 Lichen & bryophytes 6.4x10 -3 SUM1.4x10 2 2.94.3x10 1 Organism – ERICA Tool and EA R&D128 include organisms with comparatively high CR values (Lichen&Bryophytes, fungi) – not included in RESRAD-BIOTA Guidance values – Fungi U (& Ra) CR values in R&D128 are guidance values. Values used ≥10x higher than data for fungi

30.  Can be considerable variation in screening tier results  Some of variation can be understood:  CR and k d (including if 95%’ile, maximum, best estimate used)  Organism  How sediment and water inputs used  Input options  Exposure geometry  Other Tier 1 type approaches being developed  Need to compare & understand before application www.ceh.ac.uk/PROTECT

31.  Do not use/accept out of date approaches – unless justified  Be aware of potential changes as a consequence of recent transfer parameter reviews  Ensure no misuse of default values provided by various approaches  Use alternatives where justified  There are differences between approaches  Dosimetric methods tend to give similar results  Transfer parameters can add significant variation  Screening tiers www.ceh.ac.uk/PROTECT