In 2011, an earthquake and subsequent tsunami caused a devastating meltdown at the Tokyo Electric Power Co. plant.
The newly activated technology is intended to create a barrier of frozen soil between the plant and groundwater to prevent any contamination from seeping into the sea.
Right now, TEPCO is treating and storing thousands of tons of water that pass through the facility. But the plant's running out of storage space; the ice wall is meant to help with that issue.
The company's news comes the same week Japanese media reported public prosecutors would not pursue charges against the plant for allegedly violating environmental law.
After plant failures, plaintiffs, including nearby residents, filed criminal complaints alleging TEPCO allowed contaminated water to seep into the sea.
This video includes images from Getty Images and a clip from CBS.