State lifts Kaktovik do-not-drink water order

Kaktovik residents can drink their tap water again. The Alaska Department of Environmental Conservation lifted its do-not-drink order Saturday, three weeks after lab tests found ethylene glycol, a toxic chemical used as antifreeze, including in heating systems, in the village's water, according to a North Slope Borough public service announcement.

Residents may again use the public water system for drinking, cooking, brushing teeth and making ice. The borough's Public Works department is offering free, optional tests of household taps and will provide bottled water to anyone who asks for a test until it's done. Residents don't have to wait for results to use the water.

The trouble began Aug. 16, when a plant operator used a mislabeled chemical container while mixing a disinfectant solution, according to the borough. The affected South Tank was shut off from the system, and the North Tank was believed to be unaffected.

State environmental and health officials initially calculated that the water contained about 0.024 milligrams of ethylene glycol per liter, and residents were told it was safe. On Sept. 5, a lab test found 26 milligrams per liter in the water distribution system, and the state issued the order that day. The borough said then that the source had not been confirmed.

Crews later removed a failed heat exchanger connected to the North Tank. Six water samples collected Sept. 14 showed no glycol at levels the test could detect, according to a Sept. 23 borough update. Samuel Simmonds Memorial Hospital in Utqiaġvik tested more than 65 residents and found no signs of ethylene glycol poisoning.

The borough has said its first assessment was based on the reported amount of chemical involved, the South Tank being shut off and the belief that the North Tank was unaffected. It also planned to discharge 1.5 million to 3 million gallons of water with low levels of the chemical into Kaktovik Lagoon while pumping out the North Tank, and to upgrade all its heat exchangers and pressure-test the piping that heats the water reservoir.