Abstract
The removal efficiency of moderate levels of radon from groundwater supplies was evaluated using the diffused bubble aeration technique. An aeration system was designed, constructed and operated for that purpose. The effect of air-to-water ratio and detention time on radon removal were evaluated through 32 runs. The possibility to reduce the radon activity in the influent stream to the U.S. Environmental Protection Agency proposed maximum contaminant level (MCL) was verified through many alternative combined values of both air-to-water ratios and detention times. The results showed that at detention time of 19 minutes and air-to-water ratio of 12, the average radon removal is about 97%. The stripping constant characterizing this system was calculated and the removal efficiency at extended values of detention time was predicted. The data obtained are site specific, being dependent on container size, type of diffusers, temperature, and influent radon radioactivity.