The environmental challenges we face today include all of the same ones that we faced more than 30 years ago at the first Earth Day celebration in 1970. In spite of the unflagging efforts of environmental professionals (and others), environmental problems remain. Many large metropolitan areas continue to be plagued by smog, beaches are periodically polluted by oil spills, and many running waters (rivers and streams) still suffer the effects of poorly treated sewage and industrial discharges