Officials in Ely, Minn., expect crews to be working through the weekend to clean up an estimated 4,800-gallon gasoline leak stemming from a broken pipe at a local service station.

Workers at a Holiday Station Store on Sheridan Street and 11th Avenue first reported the spill, then estimated at 30 gallons, on Monday morning after seeing the fuel on the ground and leaking into the city's storm sewer system.

Officials later determined that the leak had sent an estimated 150 gallons of gas into the sewer system, with a fraction of it flowing into Miners Lake, Ely Mayor Chuck Novak said.

"After the close of business on Sunday, something failed where a pump turned on and nobody was pumping gas," Novak said.

The gas that was leaking was being pumped directly into the ground around the tanks, he explained, and when the area was saturated, some flowed into the city's storm sewer system.

A cleanup company was called in to soak up the lake spill quickly, he added.

The total amount spilled was later estimated from inventory levels taken Sunday night at the store's closure and Monday morning at its opening, Novak said.

Later in the week, workers drilled holes into the ground at the leak site and extracted about 1,000 gallons of liquid — a mixture of water and gas. They hadn't yet determined on Friday how much gas was in the liquid.

A plumber will be monitoring storm- and wastewater sewers for any further evidence of leaks, Novak said.

No injuries were reported as a result of the leak, though one town resident reported gasoline fumes in a basement.

The Minnesota Pollution Control Agency is overseeing the cleanup. The state fire marshal, the local fire department and several contractors are also on the scene.

Novak said most of the fuel is believed to be located at the gas station site.

"It's turned out to be an advantage, for once, that the whole system is sitting in ledge rock," Novak said. "Kind of like a bathtub, it can't get out of the rocks."