Originally posted by the Voice of America. Voice of America content is produced by the Voice of America, a United States federal government-sponsored entity, and is in the public domain. June 17, 2011 No Evidence of Chemical Threat at US Military Base in S. Korea Steve Herman South Korean technicians conduct a ground-penetrating radar survey of alleged burial of a highly toxic defoliant at Camp Carroll, a US army logistics base, southeast of Seoul, June 2, 2011 Photo: AP South Korean technicians conduct a ground-penetrating radar survey of alleged burial of a highly toxic defoliant at Camp Carroll, a US army logistics base, southeast of Seoul, June 2, 2011 U.S. officials say they are optimistic a joint investigation underway with the South Korean government will conclude that there are no present environmental dangers from the alleged burial, decades ago, of toxic chemicals on a American military base in the country. U.S. Ambassador Kathleen Stephens told reporters in Seoul on Friday potential health concerns to South Koreans, American military personnel and their dependents prompted a quick and full investigation. "We've got to figure out what happened," she said. "These are charges that date from over 30 years ago. But I think we've made some progress in doing that. And this joint investigation is going along and will continue until we feel that we've addressed the issue to the satisfaction of all concerned." Lee Won-seok, a researcher at South Korea's National Institute of Environmental Research, says there is nothing alarming from preliminary findings near Camp Carroll, a U.S. military base covering 40 hectares, in the southeastern part of the country. Lee says the levels of dioxin detected at three locations two kilometers from the U.S. facility are too minute to be hazardous to humans. South Korean and U.S. officials also say there is no evidence, at this stage, that the dioxin came from the defoliant Agent Orange. Scientists say they are continuing to evaluate more water samples. Results of remaining inspections are expected to be released next month. Dioxin is a compound of the chemical, previously used to clear jungles during the Vietnam War and along the Korean Demilitarized Zone. An investigation was quickly launched after three U.S. military veterans told a television station in the U.S. state of Arizona that they were ordered to bury Agent Orange at the Army camp in 1978. U.S. military records indicate barrels of chemicals and soil were removed from the bases in 1979 and 1980, but American officials say the documents do not reveal if the chemicals removed included Agent Orange. There have been concerns that the revelations of alleged dumping of toxic chemicals could re-ignite anti-American sentiments in South Korea. The United States has more than 28,000 military personnel stationed in the country.