Tokyo Electric Power Co. plans to discharge some groundwater that has flowed into the premises of the crippled Fukushima No. 1 nuclear plant into the sea after finding that its radiation level is the same as in the rivers in surrounding areas, sources said Wednesday.

Groundwater has been flowing into reactor buildings and getting mixed with highly radioactive water accumulating inside. Tepco has built a dozen wells to pump out the groundwater before it seeps into the buildings and becomes contaminated.

As a trial, Tepco pumped out about 200 tons of groundwater using the wells. Its density of radioactive substances was "the same as rivers in surrounding areas," according to Tepco officials.

The utility hopes to hold a meeting with local fishermen Monday to seek approval of the groundwater release, the officials said.

The plant has been plagued with highly radioactive water accumulating inside reactor buildings and adjacent turbine buildings as a result of the continuing injection of water to cool the three reactors that suffered meltdowns in March 2011.