Effluent for Irrigation — A Need for Caution?a

Abstract

ABSTRACTMost municipal waste treatment systems receive, treat, and eventually discard to some segment of the environment storm runoff and liquid wastes from all industrial, commercial, and domestic areas and establishments in the community. At any given time these wastes may contain viruses, antibiotics, hormones, nutrients, weedkillers, fungicides, pesticides, trace metals, and an almost countless number of toxic chemical compounds. Present treatment by the old, ineffectual sewage treatment methods and facilities still employed generally does not remove nor reduce to a harmless state all of the hazardous materials contained in the waste streams entering the plant. Some are more concentrated when they leave the plant in effluent and sludge than they were upon entry.Existing pollution protection laws prohibit surface‐water dilution of these effluents and sludges. Drying, burning, or distilling them is very costly, causes air pollution, and produces potentially hazardous chemical residues which still must be disposed of in some nonpolluting fashion. There are no “technologically feasible, economically reasonable” alternative methods of effectively treating these wastes to an acceptable quality level for discharge to streams. For these reasons, land disposal of sewage effluent and sludges now is being widely promoted and employed as the best available method of treatment.It is estimated that as many as 300 municipalities have gone to the land to solve their sewage plant waste problems in recent months. Many of these have been at least partially funded with State and Federal grants. If similar permits and financial assistance continue to be granted in the future, it is anticipated that several thousand municipalities will follow suit within the next few years.