The total cost of cleanup and repair for a spill that dumped 137 million gallons of raw sewage into the Tennessee River could be more than $40,000, officials said Tuesday.

"I think that's a high-ball figure," said Jerry Stewart, director of waste resources for the city's Public Works Department. "I expect it to go lower."

An electric outage led to eight pumps failing and sewage leaking into the river last Tuesday at five locations. It took more than 18 hours before the pumps came back online early Wednesday morning, city officials said.

Mr. Stewart showed a slide presentation to the City Council on Tuesday that broke down costs of the emergency repairs for getting the Moccasin Bend Treatment Plant back up and running again.

He said those costs would come out of the city's sewer fund.

The costs included electrical contractors, generator rental fuel and labor, documents show. But some council members wondered if the expenses could go much further than repairs and cleanup.

"Do you foresee any kind of penalty from TDEC (Tennessee Department of Environment and Conservation)?" asked Jack Benson, council chairman.

"That's up to them," Mr. Stewart responded.

But TDEC officials said Monday they would not assess any penalty, knowing that the spill was unintentional.

"Since the city informed WPC (Water Pollution Control) and worked diligently to resolve the problem as quickly as possible, they will not be subject to enforcement specifically related to this incident," said Meg Lockhart, TDEC spokeswoman.

Questions still remain on how the electrical system shorted. Mr. Stewart said Tuesday he is not sure if officials would ever know the exact cause. At this time, the plant's staff is looking at inspecting the plant's entire electrical system to make sure nothing is outdated, he said.

Councilman Manny Rico, chairman of the Public Works Committee, said he still is worried that there could be some kind of fallout from the spill. State and federal regulators are scheduled to meet with city officials this year to start working out a consent order for fixing sewer and stormwater problems.

He wondered if this could come up within those meetings, he said.

"We're talking big money here," he said.

Mayor Ron Littlefield said this week he was not worried about the event coming into play during those negotiations.

He said he had heard that there would be no penalty.

"If you can't predict it, what good does it do to fine you for it?" he asked.