People can safely resume using water from the Whitesburg water system, the state Department for Environmental Protection announced Wednesday afternoon.
An estimated 3,000 households in the city and parts of Letcher County had been warned against using the water for drinking, cooking or bathing since Feb. 16.
That was when state inspectors confirmed that diesel fuel had contaminated the city's water source, the North Fork of the Kentucky River.
The state cited Don Childers, whose company owns dozens of gas stations. The state alleged the leak came from damaged petroleum-storage tanks Childers owned at a site on the river.
Test results the state received Wednesday showed there was no longer any measurable level of diesel fuel in the water, state officials said.
"I'm really thrilled that we can go back to using our water," said Letcher County Judge-Executive Jim Ward.
For more than a week, people used gallon jugs of water provided through the city and county for drinking, cooking and hygiene needs.
At least one person, Peyton Reynolds, has sued Childers' company, alleging that because it failed to warn people of the spill, he drank the water and became physically uncomfortable and ill.
Whitesburg Mayor James W. Craft said workers dumped a million gallons of water as they flushed the system to clean it. In addition, the cost for increased testing is likely to be tens of thousands of dollars, and the city will lose revenue from the time customers couldn't use the water, Craft said.
Ward said the city and county are discussing ways to avoid a recurrence of the outage, such as installing a boom to deflect floating contamination from the water plant or a detection system to shut down the plant if it senses hazardous materials.