ABSTRACT
Since the first measurements of 222Rn in Cambridge University's water system in 1902, 1 extensive work has been done concerning the problem of 222Rn in potable water in various parts of the world. Recent measurements of 222Rn in groundwater in the United States (excluding Maine and New Hampshire) have shown values up to 30,000 pCi/L; the granite and pegmatite areas of Maine and New Hampshire, however, yield values of up to 1,300,000 pCi/L. 2•3
This report follows 12 years of work designed to locate homes with high values of 222Rn in the state of Maine.4-6 Past measurements and calculations of the radon exposure due to use of potable water appeared in papers by Duncan, Gesell, and Johnson2 in 1976 and by Gesell and Prichard7 in 1978. Duncan et al. estimated that a house of 2.0 x 105 liters volume (V) and one air change per hour(},) using 1000 L of water per day (W) would have 0.1 pCi/L in its air (Ca) for 500 pCi/L of radon in its water (Cw).
