Geofoam blocks used for 12th bridge reconstruction

SIOUX FALLS - If you've recently driven by the 12th street bridge reconstruction project, you've probably noticed some big white foam blocks. So what are they?
Construction crews are using these Geofoam blocks instead of dirt to back fill the bridge.
"The benefits of using this are it's not impacted by weather it is easy for construction crews to use it. They cut it, they slice it to fit the area they need. We are using it in our bridge because we have such a restricted construction limit it is very difficult to get dirt in it and get it pack correctly," Project Manager Dena Knutson explained to KSFY news.

This is one of the first times South Dakota has implemented this new construction technique.