Partial delisting of Twin Cities Army Ammunition Plant from state Superfund list


Arden Hills, Minn. – The Minnesota Pollution Control Agency (MPCA) today removed soil and surface water at the former Twin Cities Army Ammunition Plant (TCAAP) from the state’s Superfund list. This action follows the U.S. Environmental Protection Agency’s partial delisting of the site from its National Priorities List in September 2019. Groundwater contamination associated with TCAAP will remain on the state and federal Superfund lists until the cleanup goals have been achieved. 

Ramsey County purchased 427 acres of the larger TCAAP site in 2013 and over the next three years cleaned up the soil to residential standards, under the oversight of the MPCA. The combined purchase and cleanup cost was $30 million. During demolition of the remaining buildings, 93% of the concrete, metal and other materials were recycled or reused.

“We are pleased that TCAAP soil and surface water has been removed from the state and federal Superfund list. This is a testament to Ramsey County’s longstanding commitment and work with partners to return this property to the economic and social engine that it once was,” said Ramsey County Board of Commissioners Chair Toni Carter. “We are proud that what was once the largest Superfund site in the state will always be safe for our residents to live, work and play.”

The TCAAP property was placed on the federal National Priorities List as the New Brighton/Arden Hills Superfund site in 1983. As a part of the remediation work, Ramsey County worked with the MPCA through its Voluntary Investigation and Cleanup program and was issued a Certificate of Completion in 2016 for the 427-acre redevelopment area. The U.S. Army will continue to operate the existing groundwater cleanup system on the site for many years to come.

“For 30 years, local, regional and state leaders have been working to clean up the former Twin Cities Army Ammunition Plant,” said MPCA Commissioner Laura Bishop. “This is a major milestone only made possible by strong partnerships and a relentless commitment to improve the environment and vitality of the north metro.”

In 2016, Ramsey County and the City of Arden Hills selected Alatus LLC as the developer for Rice Creek Commons, the proposed development at the TCAAP site. The county is committed to moving forward with this transformative development to include a mix of affordable and market-rate housing with retail and commercial properties.

“Rice Creek Commons is an unparalleled development opportunity to create an eco-friendly community on what used to be one of the most polluted sites in the country,” said Ramsey County Commissioner Nicole Frethem, who represents the area surrounding Rice Creek Commons. “Now that the soil has been delisted as a Superfund site, we need to work together as partners to ensure that we are getting the maximum potential from this site for our residents and the future of our county.”