Tabulated data presenting the results of field measurements and elemental analyses for ground water, stream water, and stream sediment samples taken from data collection sites in the state of Illinois. Neutron activation analyses are given for U, Br, Cl, F, Mn, Na, Al, V, and Dy in ground water and stream water, and for U, Th, Hf, Ce, Fe, Mn, Na, Sc, -Ti, V, Al, Dy, Eu, La, Sm, Yb, and Lu in sediments (see pages 23-38 of report).