AWWA JAW20699

Two processes were investigated in the laboratory to determine their efficiency for removing radon from household water supplies. Granular activated carbon (GAC) adsorption was found to be extremely effective as a result of an adsorption-decay steady state that is established quickly and continues for years. Because bed replacement is not a factor for practical purposes, GAC is the most cost-effective process for radon removal. The GAC bed, however, adsorbs radon progeny as the radon decays, and it becomes a source of gamma radiation. This problem is believed to be manageable for the vast majority of potential applications. Diffused bubble aeration was found to be as effective as GAC, with removals of greater than 99 percent being practical. Although more costly than GAC, aeration does not have the problem of gamma activity buildup. Includes 24 references, table, figures.