‘Reeked of bias’: USC, Silfab at odds over school’s new risk assessment
Silfab Solar challenged the findings of a new University of South Carolina study the company says is riddled with inaccuracies.
USC’s Arnold School of Public Health released a report on Sunday that found people nearly 3.5 miles away from Silfab’s anticipated solar cell manufacturing plant could be impacted by a chemical spill if one happened.
At the request of residents, the school did a health risk assessment of what would happen in the event of a worst-case scenario release of four chemicals Silfab plans to store and use at the facility.
But the university never contacted Silfab while writing the report, which led to “inaccurate and incomplete” information, according to Silfab’s director of operations.
“It’s very disappointing that, almost an hour from here, a major university completes a study and doesn’t reach out to us,” Greg Basden said. “We would’ve loved to collaborate with them.”
USC did not respond to multiple requests for comment by phone and email.
What’s in the USC report on Silfab risks?
Hydrochloric and hydrofluoric acids clean and etch solar cells, according to Silfab spokesperson Denada Jackson. Anhydrous ammonia helps the cells absorb sunlight, and silane coats the cells to ensure they last longer.
Those are the four chemicals fueling the controversy. Concerned community members have long argued they are too dangerous for an area zoned for light industrial activity.
Residents banded together in the “Move Silfab” movement to prevent the company from opening in Fort Mill. Move Silfab organizers later established the nonprofit Citizens Alliance for Government Integrity, which is entangled in two lawsuits against the company and has raised tens of thousands of dollars toward their fight.
Citizens Alliance commissioned the USC study to get a neutral assessment.
The first phase of the report relied on a web-based hazard modeling tool from the Environmental Protection Agency to simulate chemical releases and assess consequences in the community.
Hydrochloric acid carried the farthest-reaching potential impact, according to the report, with a risk radius of 3.4 miles. Hydrochloric acid is highly corrosive and can cause severe burns or respiratory damage.
Silfab is slated to operate adjacent to two new schools, Flint Hill Elementary and Flint Hill Middle. Dozens of other schools, daycares, apartments, hotels and retirement communities fall within that radius.
Anhydrous ammonia and hydrofluoric acid also stretched into North Carolina with radii of 2.2 and 2 miles, respectively. Silane posed the most localized risk with just a 0.2 mile radius.
It’s unclear what future phases of the report might cover or what health risks residents who fall within those radii could experience. A spokesperson with the Arnold School of Public Health did not respond to requests for comment on Monday, Tuesday or Wednesday.
Silfab: ‘That’s inaccurate.’
The report “reeked of bias” because it is funded by activists, Basden said. He had a couple primary concerns with the university’s findings.
The report evaluated risks based on a rural setting rather than an urban one. It did not account for trees and buildings that could limit contamination, he said.
“That alone exaggerates the dispersion,” Basden said.
The study also did not account for the company’s existing containment measures. Silfab has “redundant controls” that would prevent catastrophic releases.
For example, Basden said hydrochloric and hydrofluoric acids each have multiple layers of containment within an enclosed building. If a tank leaks, a secondary containment vessel would capture the chemical. If the secondary vessel leaks, the building would contain it.
“It didn’t paint the whole story, which can lead to fear mongering. It just excites a group of people that are already excited,” Basden said. “Their worst case is all 52,000 pounds of hydrochloric acid runs out into the parking lot basically. The chance of that happening is zero.”
Silfab, USC offer opposing findings
Silfab completed its own off-site consequence analysis as part of an EPA-required report published on its website. The EPA certified that report in October.
The company found the worst-case scenario for silane involved a vapor cloud explosion impacting a 0.2-mile radius. That tracks with USC’s findings.
The two diverge on other calculations. If a full container of 22,000 pounds of anhydrous ammonia spilled, its impact would stretch up to a 1.2-mile radius. Hydrofluoric and hydrochloric acids would only impact a 0.1-mile radius, according to the Silfab analysis. Those are significantly lower risks than USC calculated.
“Any chemical, if mishandled, it can be dangerous. Anything in your pantry, anything in the aisles of Lowes,” Basden said. “The difference is our processes are highly regulated.”
Citizens Alliance board member Scott Jensen said he questions the accuracy of Silfab’s findings. His group commissioned the USC study to look into the situation and report the truth, good or bad.
“They’ve been doing this kind of semiconductor and solar factory research and analysis for decades. Silfab has never constructed a solar cell facility before. Which organization would you trust?” Jensen said. “I would rather trust the university than the company trying to get away these unlawful permits.”
Is Silfab safe? Concerns remain
The university isn’t the first outside party to weigh in on potential risks the chemicals pose.
In February, the Southeast Pediatric Environmental Health Specialty Unit at Emory University sent a letter to the Fort Mill School District warning the types and quantities of chemicals used by Silfab are concerning and warrant a closer look. The group behind the letter is considered a leading authority on preventing and managing pediatric health issues that result from environmental exposures.
“Children are not miniature adults: meaning they are not exposed to hazards in the same ways or amounts as adults,” states the letter signed by Emory University assistant professor Abby Mutic, who leads the Southeast network. “Due to their rapid development and immature biological systems, young children are especially vulnerable to harmful exposures and subsequent negative brain and lung health effects, resulting in missed school days and reduced opportunities to engage in early learning.”
At health experts’ suggestion, the school district is searching for a firm to conduct an environmental evaluation of how Silfab might impact the two new schools opening next door.
This story was originally published May 8, 2025 at 5:00 AM.
