The exact date and time of this release is uncertain but uscg and noaa involvement began june 16, 1995

Original warning text

Ferrous Sulfate Barges; Waveland, Mississippi.
Waveland, Mississippi.
1. The exact date and time of this release is uncertain but USCG and NOAA involvement began June 16, 1995. It is possible that the release was gradual over the course of weeks or months until the material released reached a level that caused a visible reaction in the waters of the barge canal. The spill site is actually two water bodies; an industrial barge canal in Bienville Industrial Park and a freshwater riverine/marsh habitat in the adjacent Mulatto Bayou. Mulatto Bayou runs somewhat parallel to the barge canal with several bank cuts allowing water interchange between the two. Hopper barges RL-224 and RL-229 had been alongside the industrial park at the dead end of the barge canal for several weeks and several months, respectively. Their cargo of dry ferrous sulfate was destined for Eaglebrook Inc. but was rejected because it was out of specification for their needs. Ferrous sulfate [...]
2. COMMODITY: FERROUS SULFATE (DRY CARGO).
3. POSITION 30.250N 089.550W. NOAA INCIDENTNEWS 7100: https://incidentnews.noaa.gov/incident/7100