The Environment Ministry said Sunday that full-fledged efforts to decontaminate areas highly polluted by radioactive matter from the Fukushima Daiichi nuclear plant disaster cannot begin until late March or later.

The government needs time to obtain the consent of individual landowners and to secure temporary storage sites for contaminated soil removed from irradiated areas, ministry officials told a panel of experts commissioned to discuss the issue.

At the meeting, the ministry also presented the panel with its draft guidelines for how to go about the cleanup work in areas contaminated with radioactive material emitting one to 20 millisieverts of radiation per year, excluding naturally occurring radioactivity.

While the national government will directly take charge of decontamination in the no-go zone and areas with annual radiation of 20 millisieverts or more, municipalities are to undertake the work in other contaminated areas, using state funds and the guidelines under a special law to take full effect in January.

According to the guidelines, due to be made official later this week, the cleanup work for houses is to prioritize eliminating radioactive cesium accumulated on rooftops, among fallen leafs in gutters, and in moss and mud.

Radiation is to be reduced to less than 1 millisieverts per year and no more work is basically required once that goal is attained.

Contaminated soil, after being removed, is to be stored in locations a certain distance away from residential areas.