Analyses of H+, SO=4, and NO-3 concentrations in precipitation from five Eastern U.S. sites between Virginia and upstate New York indicate that monthly weighted concentrations of SO=4 are highly correlated between sites out to the farthest site separation distance (750 km). NO-3 concentrations, however, are significantly correlated between sites out to 600 km site separation, a value intermediate between SO=4 and NO-3, as would be expected. These results suggest that SO2 and/or SO=4 (factors producing SO=4 concentrations in precipitation) are well mixed over the Eastern U.S. A sulfur reservoir that fluctuates uniformly within this region can be inferred. NO-3 does not show the same tendency for consistent fluctuation over large separation distances.