The EPA estimates that approximately 13 million people in the United States alone routinely drink water containing arsenic at concentrations greater than allowed under recently established government standards. The EPA’s new Arsenic Rule requires treatment for all public drinking water systems with arsenic levels greater than 10 parts per billion (ppb), by January 2006. This represents a dramatic decrease from the current standard of 50 ppb. Small public water systems serving less than 10,000 people will be financially impacted most from the new arsenic rule. The EPA demonstration program is an aggressive program to further qualify commercially ready technologies that result in significant cost savings.