(Colerain Township, OH) -- The work to clean up an oil spill in a nature preserve continues this weekend.  Crews have been in the Oak Glen Nature Preserve since Monday night, when the broken underground pipe was detected.

A press release from the Colerain Fire Department says since the 24-hour-a-day effort started, crews have collected more than 30,000 gallons of oil and water from the site near the Great Miami River.  The mixture is kept in tanks on site, and as it settles and separates, they'll have a better idea of how much oil they have actually collected.

An estimated 21,000 gallons poured out of the underground pipeline.  Click here for photos from the EPA.

The owner of the pipeline, Sunoco Logistics, is working on fixing the break, but they're not sure yet how long it will take. 

Crews are still cleaning up a creek where much of the crude oil flowed.  The Environmental Protection Agency says the creek has "heavy contamination", and they planned to flush it with clean water, on Saturday.

As they clean up the oil, workers are also capturing wildlife, like crawfish, salamanders, and at least one frog, that have come out of hibernation.  They are being evaluated for contamination.  The press release says all animals captured will be reintroduced into "regional habitats" if possible.

The Hamilton County Public Health District has been testing nearby groundwater wells, and has not found contamination.  They planned to drill more wells for more testing.

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