Skip to main content

A Review of the Radiological Assessments Corporation's Fernald Dose Reconstruction Report (1997) / Chapter Skim
Currently Skimming:

ADDITIONAL COMMENTS
Pages 36-39

The Chapter Skim interface presents what we've algorithmically identified as the most significant single chunk of text within every page in the chapter.
Select key terms on the right to highlight them within pages of the chapter.


From page 36...
... The 2 methods differ essentially in how the original radon source term is obtained. They use the same assumptions regarding escape to the outside air before and abler the 1979 sealing of major openings in the silos, and both assume that diurnal warming of the headspace is the principal driving force to radon release.
Read the entire page →
From page 37...
... CONVENTIONAL METHOD | Radium inventory to process waste ~ Radon emanation into silo headspace ~ | Radon inventors all headrace ~ l Radon release to ambient air by free flow through openings (pre-1979) Radon release through cracks in dome (post-1979)
Read the entire page →
From page 38...
... If one assumes substantial "unconstrained" leakage to the outside under pre-1979 conditions, the concentration would decrease greatly, and the transient concentration in the headspace would be determined by the radon influx from emanation from the waste mass, governed by the 3.68-day half-life of radon-222, and the outflow "leakage" rate via major cracks in the dome. Because there was no obvious entry path to replenish air losses vented to the outside other than inflow through the same cracks during the nightly air-volume contraction, the amount of air and hence the radon lost by diurnal warming are necessarily small; however, actual radon concentrations would be substantially lower than the "steadystate" inventory estimated above.
Read the entire page →
From page 39...
... Page N-4 quotes a lower-bound estimate of total radon releases from the 2 silos as 7 X lo6 pCi/s, corresponding to 2 X 10~ psi for an S-h daytime release in a volume of 2-6.3 X 107 I This would represent 2-3 headspace volume changes per day an unlikely scenario, in that it would lead to immediate depletion of the radon in the headspace.
Read the entire page →

Key Terms

  • source term
  • fundamental differences
  • headspace volume
  • estimating radon
  • substantially lower

  • diurnal warming
  • radon emanation
  • transient concentration
  • flow diagram
  • estimated radium

  • assumptions regarding
  • waste volume
  • immediate depletion
  • original radon
  • daytime release

  • unlikely scenario
  • uranium tailings
  • radium content
  • obvious entry
  • rac task

  • inventory estimated
  • assumes substantial
  • gravitational settling
  • outside air
  • waste material

  • fractions ranging
  • barely sustained
  • decrease greatly
  • radon release
  • silos contained


    • This material may be derived from roughly machine-read images, and so is provided only to facilitate research.
    More information on Chapter Skim is available.