Environmental geology / Edward A. Keller, with assistance from E. M. Burt. Keller, Edward A., 1942- Burt, E. M., joint author. Environmental geology. QE33 .K38 1979 550 KEE Includes bibliographical references and index. Columbus : Merrill, c1979. c1979. 1979 Text xii, 548 p., [10] leaves of plates : eng