Mercury in wastewater

Because there are few major natural sources of mercury and since most inorganic compounds of this element are relatively insoluble, it was assumed for some time that mercury was not a serious water pollutant. However, in 1970, alarming mercury levels were discovered in fish in Lake Saint Clair located between Michigan and Ontario, Canada. A subsequent survey by the U.S. Federal Water Quality Administration revealed a number of other waters contaminated with mercury. It was found that several chemical plants, particularly caustic chemical manufacturing operations for the production of chlorine and sodium hydroxide, were each releasing up to 14 or more kilograms of mercury in wastewaters each day. 

Mercury in Wastewater. Mercury-containing wastewater has several sources ... 

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