Dr. Barry Kim, WERI faculty and associate professor of water engineering, spoke with the Guam Daily Post regarding the recent warning to more than a thousand Yigo customers about the dieldrin chemical contamination of a water well.
The article is written by Nestor Licanto of the Guam Daily Post. Read the full article below or through the Guam Daily Post.
The Guam Waterworks Authority’s recent warning to more than a thousand Yigo customers about the dieldrin chemical contamination of a water well may “open the eyes” of the public as to how serious the situation is, said Barry Kim, an associate professor of water engineering at the University of Guam’s Water and Environmental Research Institute, or WERI.
“If I received this kind of notice, I’m not going to drink tap water anymore,” Kim said. “Instead, the best way is to buy water from a water store, bottled water, … or if you’re going to install some small reverse osmosis system.”
Kim said the issue began decades ago when Guam relied on the insecticides aldrin and dieldrin to combat pests such as corn rootworm, wireworms and termites. It was used on farms and around homes, but the chemicals were eventually banned in the late 1980s because of their environmental persistence and toxicity to people and wildlife.
“As a result, dieldrin detected in Guam’s soils today can originate either from direct application decades ago or from aldrin that has transformed over time,” Kim said. “Most dieldrin remains locked in surface soils, but heavy rains can wash it into groundwater.”
He said Guam’s limestone aquifer and areas with slow-moving groundwater are more likely to show higher concentrations because the chemical lingers rather than flushing quickly to the coast. “Detection of dieldrin in many production wells confirms its widespread presence,” Kim added.
Kim believes there are huge gaps in waste management policy and water resource management policy that allow these issues to persist.
He said from a water-quality perspective, the most effective way to protect groundwater is to prevent contaminants from entering it in the first place. “Yet because chemical and waste management are not fully integrated with water-resource planning, the island is often forced to respond only after contamination has already occurred.”
Kim said GWA’s only option is to test for and then treat the water pollutants. “As a result, large sums must be spent on treatment to comply with Safe Drinking Water Act standards – an expensive cycle that keeps repeating,” he said.
“If there was a good waste or chemical management policy, … then GWA doesn’t have to be worried about this kind of issue. So that’s what I want to address,” Kim added.
Kim said an intergovernmental response to bridge policy gaps is now critically needed. He reserved comment on who should take the lead but said it should include multiple key agencies such as GWA, the Guam Environmental Protection Agency, the Guam Solid Waste Authority, the Bureau of Planning, and others.
“It is therefore time for a serious public discussion on Guam’s environmental policies. Addressing this issue requires strong government leadership and coordinated action to close policy gaps and protect the island’s most vital resource: its water,” Kim said.
This article was written by Nestor Licanto for the Guam Daily Post and was published online on Sep. 23, 2025.
