Article from Kyodo News :
" The concentration levels of radioactive iodine and cesium in groundwater near the troubled Nos. 1 and 2 reactors at the Fukushima Daiichi nuclear power plant have increased up to several dozen times in one week, suggesting that toxic water has seeped from nearby reactor turbine buildings or elsewhere, Tokyo Electric Power Co. said Thursday.
The announcement came as the plant operator continued to grapple with pools of highly radioactive water found on the plant's premises, with the level of polluted water filling an underground trench edging up again after the company finished pumping out around 660 tons of water.
According to the latest findings, a groundwater sample taken April 6 near the No. 1 reactor turbine building showed radioactive iodine-131 of 72 becquerels per cubic meter, with the concentration level growing to 400 becquerels as of Wednesday. The concentration level of cesium-134 increased from 1.4 becquerels to 53 becquerels.
The government's nuclear regulatory agency said it had ordered the utility firm known as TEPCO to enhance monitoring of groundwater inside the plant, which is located on the Pacific coast."