Environmental regulators are attempting to determine the scope of an oil spill that took place in Calhoun County recently.

The Battle Creek Enquirer reports that the spill was discovered June 12, on a portion of a three-inch pipe in Convis Township near Bellevue and 13-Mile Rds, and crews have been working since then to clean up the oil. The Department of Environmental Quality says that the pipe, which is three feet underground, developed a small leak and did not rupture, but it’s estimated that around 4,000 gallons of oil and 20,000 gallons of brine has been spilled.

So far, around 1,700 gallons of oil have been cleaned up, with regulators saying this spill shouldn’t affect the health of residents as it believed to have been contained to private property.

The cleanup, which is headed by pipeline owner Omimex Energy of Ludington, should be finished in a few weeks.