Mosaic Official Gives Sinkhole Repair Update

Work is progressing at the portion of the gypsum stack at Mosaic’s New Wales plant where a sinkhole formed last year, Dave Jellerson told the crowd at Ancient Islands Sierra Club Thursday night.

Jellerson, Mosaic’s senior director of environmental and phosphate projects, described the work involved in discovering a sinkhole was removing water from the stack’s pond, the investigation into the size of cavity in the stack caused by the sinkhole beneath it and the work still under way to plug the connection between the stack and the Floridan aquifer to prevent further pollution from seeping into the aquifer.

He said although gypsum stacks contain small amounts of metallic and radioactive elements, the main concern for drinking water contamination are sodium and sulfates, which are the mostly likely to move through the aquifer.

No offsite well pollution due to the sinkhole has been reported.

Jellerson said 20,000 cubic yards of a cement-like substance called grout was pumped into the hole to plug it.


He said under the consent order approved by the Florida Department of Environmental Protection Mosaic will conduct studies at its other chemical plants to determine what the risk of sinkholes are there.

This is the first sinkhole since a much larger one opened beneath another stack at the plant in 1994.

The New Wales plant, which is one of the main plants still involved in manufacturing fertilizer from the phosphate rock mined in this part of Florida, is expected to continue operating for at least another 30 years.

He said he could not say what the potential for additional sinkholes will be during the plant’s remaining operating life.

Posted in Group Conservation Issues.