Limer LMC, Assessment Calculations for C-14 Labelled Gas and ...

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throughout. The reference case is highlighted in bold. The maximum annual effectiveadult inhalation doses, greater than 1E-7, are shown in Figure 5-11.Table 5-13: Potential Effective Adult Inhalation Doses (mSv) – PIER A2 InventoryCaseRn-222Concentration inSoilPotential Rn-222Concentration inBuildingsAnnual EffectiveAdult InhalationDose(Bq m -3 )(Bq m -3 )(mSv)Min. Max. Min. Max. Min. Max.EDAVaults_1mCoarse 6.5E+02 1.4E+03 9.7E-01 2.1E+00 2.5E-02 5.3E-02EDAVaults_1.5mCoarse 2.7E+02 5.8E+02 4.1E-01 8.7E-01 1.0E-02 2.2E-02EDAVaults_2mCoarse 8.0E+01 1.7E+02 1.2E-01 2.6E-01 3.0E-03 6.5E-03EDAVaults_AsDesign n/s n/s n/s n/s n/s n/sVaults1516_1mCoarse 1.4E+03 3.0E+03 2.1E+00 4.5E+00 5.3E-02 1.1E-01Vaults1516_1.5mCoarse 5.9E+02 1.3E+03 8.8E-01 1.9E+00 2.2E-02 4.8E-02Vaults1516_2mCoarse 1.7E+02 3.7E+02 2.6E-01 5.5E-01 6.5E-03 1.4E-02Vaults1516_AsDesign n/s n/s n/s n/s n/s n/sn/s is used for values less than 1E-100.Table 5-14: Potential Effective Adult Inhalation Doses (mSv) – PIER B2 InventoryCaseRn-222Concentration inSoilPotential Rn-222Concentration inBuildingsAnnual EffectiveAdult InhalationDose(Bq m -3 )(Bq m -3 )(mSv)Min. Max. Min. Max. Min. Max.EDAVaults_1mCoarse 5.2E+02 1.1E+03 7.8E-01 1.7E+00 2.0E-02 4.2E-02EDAVaults_1.5mCoarse 2.2E+02 4.6E+02 3.2E-01 6.9E-01 8.2E-03 1.8E-02EDAVaults_2mCoarse 6.3E+01 1.4E+02 9.5E-02 2.0E-01 2.4E-03 5.1E-03EDAVaults_AsDesign n/s n/s n/s n/s n/s n/sVaults1516_1mCoarse 1.1E+03 2.3E+03 1.6E+00 3.4E+00 4.0E-02 8.6E-02Vaults1516_1.5mCoarse 4.4E+02 9.4E+02 6.6E-01 1.4E+00 1.7E-02 3.6E-02Vaults1516_2mCoarse 1.3E+02 2.8E+02 1.9E-01 4.2E-01 4.9E-03 1.0E-02Vaults1516_AsDesign n/s n/s n/s n/s n/s n/sn/s is used for values less than 1E-100.38
QRS-1443ZH-1, Version 3.0Effective Adult Inhalation Dose (mSv)1.E+021.E+011.E+001.E-011.E-021 m Coarse1.5 m Coarse2 m Coarse3 mSv1.E-03TrenchesRDA Vaults(8-14)RDA Vault 8A2 EDA Vaults(15-20)A2 Vaults15-16B2 EDA Vaults(15-20)B2 Vaults15-16Region of the LLWRFigure 5-11: Effect of Attenuation Assumptions and Method Used to EstimatePotential Rn-222 Concentrations in Buildings on Annual Effective Adult InhalationDose (mSv)The results show that for an intact, undegraded cap, the annual effective doses fromRn-222 inhalation will be negligible. However, were there to exist areas over which theinfiltration barrier was substantially degraded (either as a result of ongoingdegradation processes or as a result of intrusive human activities) and were a buildingto be constructed on those areas, then annual effective doses of > 0.1 mSv might beincurred by the occupants. This EDA assessment conclusion is consistent with the RDAassessment outcomes. Note that the results associated with the EDA vaults are lowerthan for the RDA vaults, and in particular Vault 8, and also the trenches. Therefore,the EDA assessment results show that the peak impacts essentially do not differ fromthe main RDA assessment.It should be noted that the LLWR has proposed an emplacement strategy for highRa-226 wastes that these should not be placed in the upper two half height ISO(HHISO) stack positions within the vaults; this is to reduce the likelihood of theirexcavation by humans (see Hicks and Baldwin, 2011). In the RDA assessment it wasshown that consideration of this emplacement strategy would reduce the potentialimpacts associated with inhalation of Rn-222 from those wastes by three orders ofmagnitude.In the RDA assessment (Limer and Thorne, 2011), a set of “what-if” calculations wereperformed for each of the three regions of the cap considered above for the situation ofthe facility surviving for 10,000 years and there no longer being any cap present. Thesame calculations have therefore been performed for the EDA assessment; the cases are39
Page 3: Les thèmes du portail Leçon 3Néa
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Page 24 and 25: Table 3-2: Rn-222 Inventory Informa
Page 26 and 27: Please see Table 5-1 of Limer et al
Page 28 and 29: contribute substantially to the tot
Page 30 and 31: Calculated Effective Ingestion Dose
Page 32 and 33: (a)Annual Effective IngestionExposu
Page 34 and 35: calculated annual ingestion dose fo
Page 36 and 37: Figure 5-7: Average Decay Corrected
Page 38 and 39: Figure 5-9: Calculated Effective An
Page 40 and 41: Table 5-5: Calculated Annual Effect
Page 42 and 43: Table 5-7: Calculated Annual Effect
Page 44 and 45: Table 5-9: Calculated Effective Inh
Page 46 and 47: Table 5-11: Calculated Effective In
Page 50 and 51: EDAVaults_NoCap@10000y and Vaults15
Page 52 and 53: area of the cap over vault 8 were t
Page 54: the Nuclear Decommissioning Authori

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