Traces of dioxin found in stream water near US base

Ripple effects from the U.S. military`s alleged dumping of defoliant in the 1970s will likely be contained. A Korea-U.S. investigation team announced Thursday that no dioxin was extracted from groundwater near a U.S. military base in the township of Waegwan, North Gyeongsang Province.

Experts say, however, that it is too early for the U.S. to feel relieved because on-site probes are still going on and tiny amounts of dioxin were found in stream water near the base.

○ Traces of dioxin found

The probe focused on groundwater near Camp Carroll as residents in the area use it for drinking and living. Groundwater running deep in the ground is less likely to be contaminated with dioxin leaked from waste incineration than groundwater. Once contaminated, however, groundwater could be fatal to humans.

The joint investigation`s announcement that no dioxin was detected in the groundwater near Camp Carroll means that the dioxin level was less than 0.5pg per liter, the limit that modern analyzers can detect.

The Environment Ministry said traces of dioxin are detected occasionally in stream water, as toxic material generated by waste incineration can go into stream water along with rainwater.

"The detection of an extremely tiny amount of dioxin in stream water collected near Camp Carroll was expected," a ministry official said.

When the Korean government tested all water samples from 36 rivers across the country in 2009, traces of dioxin were detected. This time, the ministry said, a further investigation is needed to determine the source of the dioxin in the stream water.

○ Residents remain anxious

Residents living near the base remain anxious, however. Those who attended an explanatory session in Chilgok County, Gyeongsang Province, said soil should have been tested first.

"How can they determine if defoliants exist in the ground just by testing water samples from several places?" a 62-year-old resident asked. "What residents want to know the most is whether there are defoliants within the U.S. base."

Another resident said, "It`s a matter of common sense that a soil test should be conducted before a water test to see whether defoliants were buried."

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