WAILUKU, Maui — The U.S. Environmental Protection Agency and the state Department of Health are seeking $4,000 in penalties from Maui County for a spill of 1.4 million gallons of treated wastewater from the Kahului Wastewater Plant in late December.

The spill was caused by a break in the berm surrounding the wastewater storage pond. The spill washed away sand at the site, damaging the storage pond structure, plant access road and perimeter fencing at the facility.

The wastewater flowed directly to the ocean and surrounding areas, and the Health Department posted warning signs.

Michael Miyamoto, deputy director of the county Department of Public Works and Environment Management, said $4,000 is a "fair" fine for the spill, which the county considers a serious event. Although it was large, the spill involved treated wastewater, not raw sewage, he said.

Laurence Lau, deputy director for environmental health at the Department of Health, said the state agency is investigating the county's wastewater operations "to see how this type of incident can be prevented."

"A sewage spill of this size is very troubling and even more so when it contaminates state waters," Lau said in a written statement.

In addition to the fine, the county has 30 days to submit an engineering analysis of what caused the break and what measures will be taken to prevent future spills. The penalty money will be split between the state and federal agencies.

The fine was based on terms set in a 1999 consent decree among the county, state and the EPA to address the problem of sewage spills from Maui's wastewater system. The EPA reported that the county completed a required spill-reduction plan and is working on a 10-year sewer line analysis and rehabilitation program.