Since 2005, the community of Sabin, Minnesota, has been a high profile U.S. EPA demonstration plant for arsenic removal. Sabin draws its water from the Buffalo aquifer, as well as two city owned wells. The combined incoming water has traditional arsenic levels at approximately 45 ppb. A new arsenic removal facility built by the city lowers these levels to approximately 10 ppb.
Sabin’s water operator, Rich Hayes, needed a solution to provide long-term system stability to Sabin’s plant. He approached Blue Earth Labs about the addition of Clearitas to his water distribution system to slowly remove built-up iron deposits within the system that had a negative effect on both maintenance and chlorine residuals. However, the EPA had a great concern that the scale removing effects of Clearitas may have the unwanted side effect of increasing the levels of arsenic and other heavy metals in the water by releasing the metals from the built-up scale. The EPA contracted with Batelle scientists to monitor these levels throughout the course of this study.
Clearitas was dosed into Sabin’s water distribution system at a rate of 2 gallon of Clearitas to 30,000 gallons of water after the arsenic removal plant. After the addition of Clearitas, chlorine residual levels improved significantly as did the turbidity issues after system flushing.
A very low dosing of Clearitas was very effective at improving chlorine residual and turbidity problems throughout the water distribution system. Also, the data provided by Batelle in this study showed that Clearitas did not have a negative effect on the heavy metals within the system, neither from scale removal nor corrosion. In addition, Sabin’s use of Clearitas will provide long-term system stability.