RALEIGH (AP) — An investigation has begun into the failure of a hog lagoon which led to the spill of approximately 1 million gallons of untreated animal waste, North Carolina environmental officials said Wednesday.

The N.C. Department of Environmental Quality’s Division of Water Resources said the spill occurred at a farm in Trenton in Jones County. A news release from the department said it was notified on Dec. 21 and immediately conducted an on-site inspection.

The department said the spilled animal waste reached Tuckahoe Creek, which is approximately 300 feet from the lagoon and flows into the Trent River. Division staff members performed an on-site inspection and collected water samples to test.