Water and Wastewater Terms Beginning S

A B C D E F G H I J K L M N O P Q R S T U V W Y Z

Significant Industrial User (SIU)

A significant industrial user includes all categorical industrial users, and any noncategorical industrial user that (1) discharges 25,000 gallons per day or more of process wastewater (process wastewater excludes sanitary, noncontact cooling and boiler blowdown wastewaters); (2) contributes a process wastestream that makes up five percent or more of the average dry weather hydraulic or organic (BOD, TSS) capacity of a treatment plant; or (3) has a reasonable potential, in the opinion of the control or approval authority, to adversely affect the POTW treatment plant (inhibition, pass-through of pollutants, sludge contamination, or endangerment of POTW workers).