pH profiles in a river system with multiple acid loads

ral oxidation of sulfuritic material in the strata of coal mines have resulted in one of the most serious water pollution problems now confronting coal-producing regions. The magnitude of this problem and the concern for its solution are re flected in the large volume of related re search and study that has been conducted during recent years. In addition, much information covering the broad scope of the acid mine drainage problem exists in the literature.1 Yet no complete solution of the problem has been formulated, and vital knowledge is still lacking in several areas. Research and study are thus con tinuing in an effort to fulfill the current needs of the situation.