Description

Sorption/desorption of species in repository or environmental conditions.

Relevance screening

Records the decision as to whether or not the FEP is relevant for consideration in the assessment. If not, a brief justification is given. If so, it is indicated to which compartments the FEP may a priori be relevant (near field, geosphere, biosphere, direct exposure).

NF/GEO/BIO/DE

NF consideration

Briefly records whether and in what way the FEP is considered in the near field part of the scenarios and models. These include the gradual release/leaching scenarios, i.e. the expected evolution, alternative evolutions and human intrusions in terms of effect on the containment capacity of the disposal system.

Impact calculations: Kd approach with lower bound values from ranges for demonstrating compliance with dose/risk constraint; Performance analysis: Kd approach with best estimate values from ranges

GEO consideration

Briefly records whether and in what way the FEP is considered in the geosphere (hydrogeology) assessment basis and models for leaching scenarios.

Irrelevant in view of the consideration of a non-sorbed solute flux (FEP 2.1.1) for establishing the GTF; Calculations for the spatial extent of contamination of the solid phase consider radionuclide-specific features (hence effects of sorption (and decay - see FEP 3.1.1))

BIO consideration

Briefly records whether and in what way the FEP is considered in the biosphere models associated with gradual release/leaching scenarios. In summary, a biosphere model is described for three biosphere receptors: a hypothetical well at the foot of the eastern tumulus, the river north of the site, and wetland zones between the disposal site and the rivers. The well yields the highest impact, and compliance with the equivalent skin dose limit needs to be demonstrated as well. The impact to non-human biota belonging to ecosystems associated with all three receptors is also assessed by means of an ERICA assessment.

Use of solid-liquid distribution coefficients for sandy mineral soils (well/river receptor) or organic soil (wetland receptor) and freshwater distribution coefficients (river receptor)

DE consideration

Briefly records whether and in what way the FEP is considered in the direct exposure scenarios and models. These include human intrusion scenarios as used in impact calculations, human intrusion scenarios considered in performance analysis to assess the potential contribution of intrusion barriers, alternative evolutions in which direct exposure could occur (crater formation following a large passenger plane crash), penalising conditions beyond 2000 years.

Residence-type scenarios where leaching from soil is considered: effects subsumed in distribution coefficients