Arsenic Trioxide
Southeast North Dakota

Site Description

The Arsenic Trioxide site consists of parts of Richland and Sargent counties, including 26 townships, in southeastern North Dakota. Between 1986 and 1992, long-term cleanup actions were taken at the site to address arsenic concentrations in ground water, which serves as the area?s main drinking water source. In 2006, EPA issued a new drinking water standard for arsenic. EPA has determined that its earlier actions were no longer protective of human health and the environment. EPA has taken new cleanup actions starting in 2005.

Current Site Status and Cleanup Actions to Date

• The original cleanup action was put in place between 1986 and 1992. It included expansion and modification of 3 water treatment plants and water hookups to approximately 330 rural households
• In 2006, EPA?s new arsenic rule lowered the drinking water standard for arsenic.
• EPA upgraded the Southeast Water Treatment Plant (SWTP) and provided water service to the communities of Wyndmere and Hankinson. This work began in 2005 and concluded in 2007.
• In 2007, EPA conducted an interim action providing bottled water to rural users.
• In 2008 new construction activities connected approximately 60 rural users to the SWTP system. Plans call for the connection of approximately 300 additional rural users whose well water contains arsenic in excess of EPA?s drinking water standard to the SWTP.

Current Funding Status

• In Fiscal Year 2008, EPA obligated approximately $1.8 million to provide water connections to SWTP for rural users.
• To date, EPA has obligated a total of approximately $17.9 million for cleanup activities at this site.

For more information, please read the Arsenic Trioxide site fact sheet (http://www.epa.gov/Region8/superfund/nd/arsenic/index.html) on the Region 8 Superfund web site.