Publication Date


Advisor(s) - Committee Chair

Nicholas Crawford, Kenneth Kuehn, Wayne Hoffman

Degree Program

Department of Geography and Geology

Degree Type

Master of Science


The United States Environmental Protection Agency (EPA) estimates that 8 to 12% of U.S. homes have radon concentrations that equal or exceed 4 picocuries per liter (pCi/l). A statewide screening of Kentucky by EPA resulted in an average residential radon concentration of 2.8 pCi/l with 17% of the homes at or above 4 pCi/l. EPA requires routine monitoring and maintenance or worker health records in mines and caves having radon daughter concentrations at or above 0.30 working levels (WL).

Bowling Green is a city located in a karst region of south central Kentucky. Residents of Bowling Green have been subjected to various environmental hazards that are closely linked with the landscape. Of particular concern has been the recurring problem of chemical fumes rising from contaminated caves and collecting in buildings.

The author has recorded radon daughter concentrations in excess of 5 WLs in caves beneath Bowling Green. A preliminary screening of residential radon concentrations in Bowling Green resulted in an average concentration of 25.8 pCi/l. Two of the test results were above 100 pCi/l and were recorded in homes that were known to have a history of fume problems. These results spurred this thesis which addresses the magnitude of residential radon contamination in Bowling Green and its association with the karst landscape.

The investigation involved radon daughter testing in Bowling Green caves and residential radon testing. A total of 84 measurements were conducted in order to establish a working average residential radon concentration for the city. Twelve other tests were performed in buildings known to have a history of chemical fume problems. The resulting average residential radon concentration was 9.06 pCi/l. First floor measurements averaged 4.73 pCi/l, and basement measurements averaged 22.92 pCi/l. The overall average for buildings with a history of fume problems was 35.15 pCi/l with first floors and basements averaging 29.75 and 57.40 pCi/l respectively. Forty-six percent of the homes comprising the sample population equaled or exceeded 4 pCi/l.

The results of the investigation indicate that:

  1. Bowling Green Caves sometime have radon daughter concentrations far in excess of 0.30 WL.
  2. The average residential radon concentration for Bowling Green exceeds the average for Kentucky obtained by EPA.
  3. The percentage of houses that have radon concentrations at or above 4 pCi/l for the study area exceeds the estimated national average of 8 to 12% and the statewide average.

The author suggests that insufficient data was collected to determine whether radon concentrations in Bowling Green homes with a history of chemical fume problems are higher than for the city as a whole.


Earth Sciences | Environmental Health and Protection | Environmental Monitoring | Environmental Sciences | Geography | Geology | Hydrology