Millenia Wall Solutions has entered a manufacturing agreement with structural foam and injection molder Structural Plastics Group to make Millenia's retention-wall products, which are designed to look like natural stone.
Edina-based Millenia previously employed three separate companies to manufacture the three separate components that make up a retention-wall unit.
``SPG allows us to do everything under one roof so we can get our costs down,'' said Peter Jonswold, account executive for Millenia, in a May 29 telephone interview.
The products are made from recycled plastics.
SPG in Sterling Heights, Mich., processes high density polyethylene using high-pressure injection molding to make the ``confinement cell,'' which holds some of the stone and backfill material. The wall unit's HDPE frame is made of a structural foam. The face piece, which is designed to look like natural stone, is made from a copolymer polypropylene, through a reverse casting of actual natural stone, Jonswold said.