VANDERBILT — An oil spill discovered last spring in Pigeon River Country State Forest will take years to clean up, but substantial progress has been made, experts are saying.
“We have cut the head off of the beast,” said Gaylord Area Senior Geologist Mike Shelton of the Michigan Department of Environment, Great Lakes and Energy. “Now we just have to deal with the aftermath.”
Kalkaska-based Lambda Energy Resources discovered the leak from a compromised oil flowline last April, 4 feet below grade in Section 14 of the forest, about 1.25 miles south of the nearest bank of the Black River.
Roughly 9,200 gallons composed of an estimated 100 barrels of condensate, 110 barrels of brine, and 11 barrels of crude oil – far more than was originally estimated – were released from the 50-year old pipeline, which failed about 580 feet down from the wellhead, at a faulty welding point, according to Shelton and EGLE Public Information Officer Josef Greenberg Stephens.
According to early reports, a thin layer of the mixture spread over about an acre of coniferous wetland in Michigan’s largest expanse of contiguous wilderness. However, the affected area also turned out to be much larger than originally thought.
“Some reports state that only half an acre has been impacted, but it is definitely more than that,” Shelton said. “As of the last report I received, a total of 6.5 acres has been impacted.
“There has been some migration to the north and northeast, but in the general aspect of the totality of the wetland itself, a very small percentage has been impacted.”
More than 6,750 tons of soil have been removed, according to Shelton, who has not yet received updated volumes of fluids removed from Lambda.
According to Shelton, EGLE’s Water Resources Division found no threatened or endangered species within the impacted area, which will make vegetation re-establishment easier.
“You can’t just make a forest pop back up,” he said. “There will be some longevity to this. The DNR will work with EGLE’s Geologic Resources Management Division (GRMD) to keep things going forward.”
In November, additional sites were found in the flow path, which had above-criteria concentrations of contaminants, according to Shelton. In response, Lambda remobilized crews in December, “to get in and dig out some of those other areas from the main release point.”
Lambda has been using vacuum trucks to pull impacted water out of installed sump systems to ensure contaminated water does go on to further impact the wetland area.
“The setting of this location is a nightmare to try to work in, but we are making progress,” he said. “There were some misconceptions that this cleanup would take a couple of months, but given the remote setting and environmental sensitivity that needs to be taken into account, it will likely be a multi-year project.
“There is no sense in negatively impacting other, unimpacted wetland to try to remediate the affected areas. We are trying to be as surgical as possible in our removal of the contaminants.”
Shelton said that if the spill had occurred in a more easily accessible location, cleanup would probably be near-complete by now.
Aerial footage from the DNR and consultant drone flights show a bifurcated surface plume, with one plume leading to the north and one to the east, toward two unnamed feeder creeks to Canada Creek.
“We had some initial increase in concentrations at those points,” Shelton said, “but nothing above criteria.”
According to sample drafts he received Wednesday morning, one of those two feeder creeks shows a drop from 110 PPM (parts per million) chloride to 30 PPM chloride. The other feeder creek, which previously tested at 47 PPM chloride, has dropped to 20 PPM chloride.
“That’s a great sign. The groundwater and surface water criteria have different protection parameters, for concentration requirements. Both surface water and drinking water levels are well below necessary requirements. Those are a couple of positives.”
Given the current decreasing levels of contaminant, he said he doesn’t believe there will be any above-criteria impact on Canada Creek, which feeds into the Black River.
“Right now, there is no pathway for Black River contamination,” Shelton said. “The horizontal aspect of the excavation seems to be under control. We still have to work on the groundwater and surface water aspects. With winter freeze, some of those difficult-to-reach access points could be potentially easier to get to, before things get mucky again.”
Lambda’s immediate response to the spill made a big difference in getting a head start on the cleanup – but there is still a lot of work to be done.
“This was a bad situation in a horrible location,” he said, recommending that people stay away from the area while cleanup work continues.
“There are still hazardous sites which still are above hydrocarbon contact requirements for people in the immediate vicinity,” Shelton said. “Otherwise, there should be no negative impacts on the general population.
“There are a lot of places that look walkable where, given the snow cover in the area, someone could feasibly fall through.”