It has been revealed for the first time that a joint South Korea-U.S. inspection conducted two years ago found high levels of carcinogens in the underground water of the Yongsan Garrison in Seoul.
The Environment Ministry disclosed the results of the joint inspection on Tuesday.
The level of benzene in seven out of 14 water samples taken from 14 wells drilled inside the headquarters of the U.S. military forces stationed in South Korea was higher than the permissible standard. Benzene is a carcinogen classified by the International Agency for Research on Cancer as Group 1.
The level of benzene in some of the seven water samples was up to 160 times higher than the permissible level.
South Korea and the U.S. carried out the joint inspection in May 2015.
The Environment Ministry belatedly disclosed the inspection results after the Supreme Court ordered the ministry last week to disclose the results of the inspection on groundwater contamination within the garrison.