226Ra and 228Ra were found in flowback water in all 3 Marcellus wells sampled for it. Levels of 226Radium
ranged from 2.58 – 33 pCi/ L and 228Radium range from 1.15 – 18.41 pCi/ L.4The EPA sets a maximum
level of 226Radium in drinking water to 5 pCi/L and 228 Radium to 15 pCi/L.