GAYLORD, Mich. – Oil and gas company officials continue cleaning up a crude oil and brine spill in the Pigeon River Country State Forest that turned out to be more than four times larger than initially estimated.

On Jan. 15, members of the state forest’s advisory committee received an update about ongoing cleanup work following an oil spill discovered last spring. A company official reported crews are working to finish removing liquids that leaked from a pipeline flowline into a wetland area last April in Cheboygan County’s Forest Township.

Those leaked materials totaled 221 barrels – an estimated 11 barrels of crude oil, 100 barrels of brine, and 110 barrels of condensate, a type of hydrocarbon liquid similar to gasoline. That amounts to more than 9,200 gallons of liquid pollution.

Previously, state officials estimated just 50 total barrels, or about 2,100 gallons, of crude oil and brine had spilled.

Nick Summerland of Lambda Energy told the state forest advisory council that most of the remediation work is completed.

“It’s been scraped. The oil is gone. There’s still chloride-impacted water that’s seeping into the sumps that are in there, but at least there’s a way to recover that,” Summerland told the advisory council.

The sumps are not expected to continue working through the winter, when the ground and surface water are largely frozen, he said.

Related: Crews respond to 50-barrel oil spill in Northern Michigan state forest

The company had to install floating mats as temporary access roads to reach the spill in the remote swamp. Crews then built berms to collect the spilled liquids and prevent the materials from spreading further.

Summerland said multiple acres of wetlands were initially affected by the spill, but about a half-acre remains impacted. The leaked liquids haven’t drifted into any creeks, though two tributaries to Canada Creek are nearby.

Workers faced extra challenges reaching the oil spill site because of an overabundance of fallen branches and trees from an enormous ice storm that damaged much of the Pigeon River Country State Forest just weeks earlier.

Steve Buyze, district supervisor for the Michigan Department of Environment, Great Lakes and Energy, said the agency is awaiting groundwater and surface water tests results from samples collected at the site last week. The analysis will help officials decide whether additional cleanup work is required.

Meanwhile, the federal Pipeline and Hazardous Materials Safety Administration sent a warning letter to Lambda Energy in October after an inspector documented problems in June and July at the company’s Kalkaska facility.

Among other concerns, the inspector reported that “Lambda failed to have an effective system for detecting leaks,” according to the warning letter.

Lambda owns and operates about 100 miles of oil pipelines and 150 miles of natural gas pipelines across Northern Lower Michigan.

There is a long history of oil and gas activity within the Pigeon River Country State Forest, where dozens of wells have been drilled dating back to the 1970s.