POLK County, Fla. (WFLA) – It was an estimated 100-foot-wide sinkhole, about 300 feet deep into the soil of Polk County that swallowed 215 million gallons of wastewater from Mosaic Fertilizer’s New Wales stack system.

It was a nightmare for everyone involved, from the company to residents to the government agencies.

The Department of Environmental Protection (DEP) and the Environmental Protection Agency (EPA) was alerted by Mosaic after the August 2016 shocker, but the public did not know about it until News Channel 8 reported what happened there.

Mosaic spokesperson Jackie Barron said the fertilizer giant learned a lot from that disaster.

“We learned right out of the gate we should’ve been more communicative,” Barron said.

Center for Biological Diversity Director Jacki Lopez said her organization is against DEP approving the permit application to allow 230 additional acres to be mined at the New Wales facility.

“I don’t know why anyone would authorize an expansion of that if there’s proven issues with it,” Lopez said. “It doesn’t make any sense.”

Barron said after the 2016 incident, Mosaic set up community advisory panels of residents who meet with the company several times a year to discuss local concerns.

According to Barron, there are also 90 wells at the facility that monitor groundwater and a new technology involving devices known as geophones that she said can detect underground movement.

“We do have the ability to do directional grouting to go in and fill any sort of void,” Barron said when asked if a problem could be stopped if detected by the geophones. “We have the technology in place.”

Mosaic says it took nearly two years and 20,000 cubic yards of grout to fill the void at the New Wales fertilizer plant.

The sinkhole cratered beneath a gypsum stack in late August 2016.

Lopez remains stunned the state would allow the expansion a mere three years after the mammoth crater was filled.

“This particular area has shown itself to be vulnerable to sinkholes,” Lopez said. “And this isn’t just speculation. We know there’s a record of problems with this gyp stack.”

Mosaic is asking the expand into a 230-acre area in the southern area of New Wales that was previously mined, according to Barron, who said it will not draw the operation any closer to residents.

“We believe with the technology in hand we can proactively respond to any issues should they arise,” Barron said. “We believe we have the resources needed to handle the stack and to manage the stack. We believe we’ve shown that to date.”

But for Lopez, the sinkhole is a warning comparable to warnings about Piney Point that were disregarded by the DEP before Port Manatee dredging material was allowed to flow into that stack system.

“Yet local officials allowed the dredge material to be placed there and many years later we see the emergency release where we had to send hundreds of millions of gallons into Tampa Bay,” Lopez said. “It’s the local taxpayers left holding the bag when regulators look the other way.”

Piney Point breeched in 2011, three years after the U.S. Army Corps of Engineers reported the system was not engineered to hold dredging material. Last month, the shutter fertilizer company in Manatee County sprung a leak again, leading to the pumping of 215 million gallons of water into Tampa Bay.

Lopez’s organization is now calling for new inspections of all active and inactive stacks in the state.

“An immediate review of all the liners. Immediate review of all the ponds,” Lopez said. “The integrity of all the stacks, in addition to what may be required by existing regulations.”

According to DEP spokesperson Dee Ann Miller, there will be a public comment period that will last 30 days from the publication of the draft permit. A letter from DEP to Mosaic estimated the draft permit would be published by April 15, but that did not happen.

The letter also estimated the permit could be issued or denied by July 8, but Miller said that date is also going to change.

Barron did not have a target date for the start of the expansion if the permit is issued.