Inside a packed courtroom Monday afternoon, Union County residents pushed back against a proposed phosphate mine they said would jeopardize their health and hurt their property values.

For about an hour, they pleaded with county commissioners.

“The land is gonna be permanently scarred,” said Lee Whitlock, a 64-year-old resident who worked in a mine in the 1980s.

For the past couple years, a private company formed by four families who own land in the county has developed a plan to mine about 7,400 acres of their land in Union and Bradford counties. The exact boundaries are unclear because no map has been released.

The company — named HPS Enterprises LLC and led by members of the Hazen, Howard, Pritchett and Shadd families — argues that the mine would create jobs and boost the area’s economy.

But some residents, who say they just learned about the plans and are organizing against the mine on Facebook, maintain the operation would do more harm than good.

Residents asked the commissioners to draft an ordinance to stop all possible permits for phosphate mines for a year until the commission figures out how to ban it permanently.

Eric Thomas, a former fisheries biologist with the Florida Fish and Wildlife Conservation Commission, began the opposition group. He gave a presentation to the commission Monday warning about the potential carcinogens present in the phosphate mining process.

One of the main concerns is contamination with radon and radium, radioactive materials that are known to be found in regions mined for phosphate, Thomas said.

“Phosphate mining is something that will put a death nail in a small community,” he said.

Thomas said the mining operation may put the county’s water supply and its residents’ long-term health at risk.

“We believe this is gonna present a major public-health concern for anyone who is near the mines but especially for those who work in them,” he said.

Phosphate mining has been a Florida staple since the 1900s and is often a long-term operation that requires digging dozens of feet into the ground and then using water pressure and machines on tracks for skid steers to excavate phosphate minerals for later use in fertilizer.

While some researchers have said this form of mining may risk water contamination and habitat loss, others say the risks are highly unlikely, and any changes to the environment are temporary because companies are required to renovate the land after use.

HHPS Enterprises has yet to request for a permit from Union County, but if it does before the commission’s ordinance is drafted, the commission would have to listen to it.

After hearing of the proposal from an article in the Union County Times last month, Thomas created a Facebook page for the opposition, which has since garnered 419 likes and about 1,500 views online.

“I immediately opposed this,” he said.

A petition against the proposal also went online and has since been signed by about 260 people.

HHPS spokeswoman Mandy Wettstein said the company’s operation, if approved, would not risk contamination or environmental damage. Representatives for the company will hold a town-hall meeting on or around March 15 and will answer questions and address concerns then, she said.

“I would ask people to do their research, visit the website when it’s released and come to the community meeting,” Wettstein said. “We’ll be discussing everybody’s environmental concerns.

“But I would also say that the state of Florida has very rigorous rules and regulations that are designed to protect the environment, and this project” will respect the boundaries set by the state.

But some critics’ concerns persist. One leader of the opposition group, 54-year-old Becky Parker, said she’s lived in Union County nearly her entire life.

In her opinion, the phosphate mine — regardless of economic benefits — would damage the beauty of her county’s unsettled wildlife, mainly along the New River, a tributary of the Santa Fe River.

After hearing news of the proposal last week, Parker said she has gone door to door bringing awareness to the cause and has spoken with representatives of the company.

“In my mind, the only thing beautiful about Union County is its country, its pristine woods and the river and the wildlife — the untouched Florida, really,” she said. “And when you take that away from Union County, we’ll be left with phosphate mines, the human refuge from the prison and a tri-county landfill.”

Wettstein said HHPS has reached out to residents, too, in an effort to be transparent. Once the HHPS website gets running, anyone will be able to see the facts and figures behind the proposal, she said.

“But at this point, we’re still in planning mode, and we’re gonna do this right — not reactionary,” she said.

Meanwhile, Thomas said virtually no one he’s spoken with had any previous knowledge of the mining proposal.

“Between me and several others, we are getting calls nearly nonstop with people who are upset about this,” he said.

Though there’s no timetable for a commission vote, Thomas said that if commissioners indeed move forward with the proposal, it will just be a matter of time before the company files for permits from the state.

“We plan to oppose it on the state level if it’s approved by the county,” he said, “but we’re very hopeful that the county commissioners will see the light.”

The Bradford County Commission will meet Thursday at 6:30 p.m. in Starke to take up the same issue.