Japan's nuclear decontamination law came into full effect Sunday, an effort that is expected to facilitate the cleanup efforts after a cold shutdown was declared at the troubled Fukushima Daiichi power plant.

According to the document, comprehensive cleanup work is likely to begin at the end of March, Environment Ministry officials said.

The decontamination plans will be crafted by more than 100 municipalities where radiation doses are estimated to exceed 1 millisievert a year on top of natural background radiation and that from medical treatment, according to local media reprots.

The document also said the country will dispose of ashes from incinerated waste and sludge if they are revealed to contain more than 8,000 becquerels of radioactive cesium per kilogram.

The water temperature in all three of the affected reactors at the plant fell below boiling point by September and the government declared a cold shutdown this month.