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page title goes here Risk Assessment

Default DCC Download Area

Default DCC tables, based on a dose limit of 1 mrem/year, are available for download in Excel and PDF formats. The summary table includes the total DCCs for select land use (resident, composite worker, farmer, and soil-to-groundwater) and media (soil, water, and air) combinations. The composite tables include the individual route DCCs and the total DCCs for select default land use and media combinations. Indoor and outdoor worker default tables are not provided, because site-specific screening is recommended for the composite worker DCCs. The composite tables also include tables of toxicity values, soil-to-plant transfer factors, and animal transfer factors.

The following table lists all available, downloadable land use and media combinations for the summary table or composite table and the default DCC type. The Peak DCC option was selected for soil and 2-D external exposure, as soil is not considered to be continually contaminated. For all other media, it was assumed that the contamination is continuous, and the secular equilibrium DCC option would be the most protective. Reasons for continuous contamination include:

  • contamination by stack emissions or emanation from soil, as is the case for radon
  • water contamination from surrounding soil
  • biota contamination due to constant contact with water and soil sources, where time from seed to harvest allows progeny to ingrow

July 2023 Tables

Included in Summary Table
Land Use Media Default DCC Type
Resident Soil Peak DCC
Composite Worker Soil Peak DCC
Farmer Soil Peak DCC
Resident Air Secular Equilibrium
Composite Worker Air Secular Equilibrium
Farmer Air Secular Equilibrium
Resident Finfish Secular Equilibrium
Resident Tap Water Secular Equilibrium
Farmer Tap Water Secular Equilibrium
Resident Soil to Groundwater Dose-based Secular Equilibrium
Resident Soil to Groundwater MCL-based Secular Equilibrium
Not Included in Summary Table, but Available in Composite Table
Land Use Media Default DCC Type
Resident 2-D Peak DCC
Composite Worker 2-D Peak DCC
Resident Tap Water Produce Supporting Table Secular Equilibrium
Farmer Biota Secular Equilibrium
Farmer Tap Water Produce Supporting Table Secular Equilibrium

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pCi Bq
(DL = 1 mrem/yr) (DL = 1 mrem/yr) (DL = 1 mrem/yr) (DL = 1 mrem/yr)
Summary Table (PDF) (XLS) (PDF) (XLS)
Composite Table (PDF) (XLS) (PDF) (XLS)