K. Hawk et al., RADON CONCENTRATIONS IN HOMES IN AN AREA OF DOLOMITE BEDROCK - DOOR COUNTY, WISCONSIN, Environment international, 19(3), 1993, pp. 241-252
A statewide survey by the Wisconsin Department of Health and Social Se
rvices with U.S.E.P.A. assistance reported an anomalously high percent
age of homes in Door County with radon concentrations in excess of 20
pCi/L. The results were of interest because the county is underlain by
marine sedimentary rocks rather than the igneous and metamorphic crys
talline types usually associated with elevated radon concentrations. A
voluntary population of 55 homes was tested for radon using activated
charcoal canisters. This population was also asked to provide questio
nnaire response data on family, home, and socioeconomic aspects. The d
ata were separated into socioeconomic, energy efficiency, radon access
, and karst level categories and statistically analyzed. A subpopulati
on was selected from the larger population for detailed site investiga
tion, which included additional in-home air testing and, at some sites
, water supply analysis and in-ground testing for radon. The field inv
estigations collected information on the geology, soil, topography, an
d home construction and use. The results of the investigation verified
and characterized the radon occurrences iu Door County. The presence
or absence of karst features is shown to be statistically significant
to radon levels.