The Naval Industrial Reserve Ordnance Plant (NIROP) Superfund site is an 83-acre site located about 700 feet east of the Mississippi River in Fridley. The U.S. Navy manufactured naval gun mounts and other missile-launching systems at the site until 2012.
Above: Governor Dayton and others break ground on a new development where a former Superfund site existed. Through the efforts of state and private partners, a large swath of land in Fridley is being cleaned up and prepped for new economic development.
Cleaning up contamination
In 1981, trichloroethylene (a common industrial solvent) was discovered in on-site groundwater wells and in the city of Minneapolis's drinking water treatment plant intake pipe, which is now located in the Mississippi River downstream from the site. There were no existing federal drinking water standards for trichloroethylene (TCE) in 1981, but the wells on the NIROP site were shut down in April 1981 as a precautionary measure.
The Navy, U.S. EPA, and MPCA began environmental investigations at NIROP in 1983 and identified volatile organic compound (VOC) contamination in both soil and groundwater. By 1996, 2,200 cubic yards of soil and 97 drums and 12 small containers of waste that were found buried on the site were excavated and disposed of appropriately.
To contain and reduce the groundwater contamination, a groundwater pump-and-treat system was built using a network of pumping wells and began operating under the oversight of the MPCA and EPA in 1991. After the groundwater is treated, it is discharged to storm sewers that empty into the nearby Mississippi River. About 265 million gallons of groundwater were pumped out of the aquifers and treated last year. Work continues today.
Hyde Development to begin redevelopment
Hyde Development entered the MPCA’s Brownfield Program about a year ago, with a plan for redeveloping this federal and state Superfund site into an office park.
The timing of the redevelopment presents a great opportunity to clean up previously inaccessible areas of soil contamination. The demolition of the remaining 1-million-plus-square-foot NIROP building — the next step in the clean up process — will give the Navy and BAE access to two known areas of soil contamination that have been inaccessible: a metal-plating shop and a paint shop. Addressing the areas of remaining soil contamination will have a positive effect on the groundwater contamination and may shorten the time that the pump-and treat-system needs to operate. The Navy will continue to operate the groundwater pump-and-treat system during the redevelopment and into the future.
The MPCA has been working with the EPA, the Navy, Minnesota Department of Health, the city of Fridley, Hyde Development, and citizen groups to make sure that the redevelopment meets MPCA cleanup standards.
For more information
For more information about the site and its history, see MPCA's Superfund sites in Fridley.
The Naval Industrial Reserve Ordnance Plant manufactured guns and gun mounts for U.S. Navy ships during World War II. Note the large slick of solvent (or possibly anti-rust chemical) on the floor. Regulations in place today protect against such cavalier handling of dangerous chemicals and materials.