KAILUA-KONA — Routine sampling of drinking water systems across the state recently turned up trace levels of organic chemicals in water collected in Hamakua.
Atrazine was detected in the Hawaii County Department of Water Supply Kapulena Well of the Kukuihaele water system, which serves approximately 450 residential customers on Hawaii Island, according to the state Department of Health. The level, 0.054 ppb, is well below the federal and state standard of 3 ppb.
Atrazine is an herbicide used on row crops such as sugar cane. Atrazine had been previously reported in the Kukuihaele water system at a level of 0.27 ppb in 2011, according to the department.
Drinking water from the well remains safe, as the trace level detected was below the U.S. Environmental Protection Agency and State Maximum Contaminant Level (MCLs), acording to the department. The standards are set to avoid human health risks based on a lifetime of consuming water containing that level of contaminant.
In addition, the sampling found trace levels of organic chemicals in water collected at the Haiku Town Water Association, Inc. water system on Maui.
Detected were 1,2-Dibromochloropropane (DBCP) and 1,2,3-Trichloropropane (TCP), according to the department. The system serves approximately 65 persons in Haiku, Maui.
The DBCP level confirmed at the well was 0.02 parts per billion (ppb), one‑tenth of the EPA MCL of 0.200 ppb. The state has a more stringent MCL of 0.04 ppb, and the concentration found was also lower than the state’s more stringent level, according to the department.
Also confirmed was 1,2,3-Trichloropropane (TCP) at 0.11 ppb, which is below the state MCL of 0.6 ppb. There is no federal standard for TCP.
The department stated the presence of DBCP and TCP in the sample is attributed to the former cultivation of pineapple on the site itself. The use of the soil fumigants containing these contaminants ended in the mid-1980s, suggesting that the detected levels are not expected to increase in the future.
“These trace levels of the chemicals do not pose a public health threat, and the waters from these wells are safe to drink,” said Keith Kawaoka, deputy director for environmental health. “The Department of Health will continue to work together with these water systems to ensure tests for these chemicals continue. Such testing is part of scheduled monitoring regularly conducted to ensure that everyone’s water is safe to drink and public health is not compromised.”
Water from these water systems is tested as mandated by federal and state drinking water regulations. To date, these water systems continue to be in full compliance with all federal and state standards for drinking water.
