It's been exactly a decade since nearly 20,000 gallons of oil spilled from a ruptured pipeline into Oak Glen Nature Preserve in Colerain Township. The spill was stopped just short of the Great Miami River, but the oil and subsequent cleanup left a jagged scar cutting through the woods.
WVXU's Tana Weingartner covered the initial spill, cleanup and restoration. She returned recently with Great Parks Chief Operating Officer Bret Henninger and Watershed Specialist Amanda Nurre. Their conversation has been edited for length and clarity.
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She started by asking Henninger to recount what happened, starting on March 17, 2014.
Henninger: There were several instances where both neighbors and passersby could smell an odd substance. Many of them called in 911 complaints because the odor was very strong. They described it as very much like a petroleum product, and [it] eventually got referred to a park ranger.
The park ranger began to investigate and then found an oil-like substance, which we later found out was crude oil, that had come from a pipeline that had burst up the hill from the preserve just off the property, and then ran through the property in a stream, and then settled in at a wetland at the bottom of the of the hill.
Move the white bar to see Oak Glen then and now.
What was the remediation process? It was about 20,000 gallons, I believe, of oil spilled.
Henninger: The first stages were getting the oil shut off and the pipeline repaired. Then the next phases were sort of around flushing the oil down and capturing it. That involved contractors that worked for the oil company that came in and would siphon oil off of the stream and the wetland.
Eventually, they had to build a containment dam on the bottom end of the stream to prevent everything that was being flushed from the top of the hill from continuing to go into the wetland. And then also, there were measures taken to keep the spill from going into the Great Miami, which is just adjacent across the road.
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What was the extent of the ecological damage?
Henninger: There were times right after the spill where we really couldn't find anything living in the stream. Then there was collateral damage, too. They had to pump a lot of water up the hill to flush the oil out. So, there's many things here: there's oil pollution, but there's also habitat degradation from scouring out all of that soil and widening the stream and deepening it and changing the flow characteristics. So there's a lot of physical damage that had to be repaired in addition to having the oil that needed to be removed.
Now we're 10 years on. Amanda, introduce yourself and explain your role at Oak Glen.
Nurre: I'm the watershed specialist for Great Parks. I've been involved in keeping an eye on the monitoring phase. Once the primary restoration was completed — and that was completed in 2018 — we moved into this 10-year monitoring period.
Currently, 2024 is year seven of monitoring. Every year, basically the amphibians, and salamanders, macro invertebrates; there's water and sediment sampling done, and all of this is being examined to see what the progress of the restoration is.
And what is the status of it? Are the salamanders back? Is the wildlife back?
Nurre: There are a lot of different performance standards that we're looking at. Some of them seem to be doing well, other ones are not back to pre-oil spill conditions. For a lot of them, they're looking at reference streams, which are streams that are similar in characteristics. We want those performance standards — like the amphibian density, for instance, or the macro invertebrate population — to be the same as in the reference stream, in those streams that were not impacted.
In some ways we are seeing a rebound, and in some ways we aren't. We still have a few more years left of monitoring, and we're hopeful that the populations will continue to rebound.
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What happens after year 10?
Nurre: The sort of finalization of all this is decided by Ohio EPA.
Henninger: It would be an EPA decision on what the next steps would be, whether it be an extension of that monitoring period, or whether it be some other repercussions, that would be in their hands.
How do you feel about where it is now?
Henninger: I think getting it back to the way it was is probably not possible. But getting it to an ecologically functional state is a good goal to have for it. So, put quotation marks that "were pleased" — I wouldn't say we're pleased, but we're glad to see things are moving along.