Louisville Gas and Electric has been issued another citation for coal ash violations at its Cane Run Power Station in southwest Louisville.

The Notice of Violation is for only one incident–on September 13, residents living near the plant reported seeing clouds of ash spewing from LG&E’s sludge processing plant for five minutes. The company reported an equipment malfunction.

The proposed penalty for the violation is $10,000, but if the company and the Air Pollution Control District reach a settlement, it might be settled for less. The notice of violation also requires the company to submit records explaining why it took so long to shut the machine down once it began malfunctioning, and how upgraded controls planned to be installed next month will keep a similar incident from happening in the future.

For the past two years, the plant’s neighbors have been reporting fugitive coal ash leaving the plant’s landfill and contaminating their homes. A year ago, LG&E was fined $26,000 a year ago for several incidences, but eventually settled for a smaller amount. And in July, the company was fined $24,000 for additional coal ash violations.

The coal-fired power plant is set to be retired and replaced with natural gas. LG&E announced earlier this month that it would shut the plant down by May 2015–eight months earlier than originally planned.