Back-to-back chemical leaks at Silfab Solar's new Fort Mill facility have parents rattled, a nearby elementary school temporarily closed and state regulators telling the company to hit the brakes. Officials insist the chemicals never left the plant, but with a halt order now in place and federal agencies stepping in, neighbors say they want more than reassuring words before the solar manufacturer moves ahead with commissioning.
State orders plant to halt operations
The South Carolina Department of Environmental Services has ordered Silfab to "immediately cease all operations," according to WBTV. In a March 5 letter, the agency told the company to secure its systems, verify there are no additional releases and bring in an independent engineer to evaluate the plant's chemical systems while state officials and the U.S. Environmental Protection Agency investigate. Regulators also directed Silfab to pause all new chemical deliveries during the probe.
Two leaks this week: what happened
County and company officials say the first leak on March 3 involved potassium hydroxide, later estimated at roughly 300 gallons and largely held within a retention pool, according to WJCL. Two days later, on March 5, York County reported a separate hydrofluoric acid release inside the plant that was captured in secondary containment, according to WMBF. Hazmat teams and private contractors oversaw mitigation and cleanup, and officials say air monitoring at the nearby school did not detect contaminants.
School closes, parents demand answers
The Fort Mill School District temporarily closed Flint Hill Elementary on March 5 "out of an abundance of caution" and rerouted buses to Pleasant Knoll Middle School while parents came to pick up students, the district said in a statement reported by WRHI. York County Emergency Management told residents the hydrofluoric acid remained within secondary containment and that there was no threat to public safety. Even so, the twin incidents have intensified scrutiny from neighbors and local leaders, who are now calling for public briefings and access to spill-response records.
Company response and legal pressure
Silfab has pushed back on the idea that the facility is unsafe, saying there was "no emergency" at the site and that the company is cooperating with investigators, according to WIS. On March 4, South Carolina Attorney General Alan Wilson sent the company a letter pressing for answers and citing parents' concerns about safety, according to the attorney general's office. State lawmakers have said they will urge regulators and the U.S. EPA to complete a full review before they sign off on any additional startup activity.
What regulators will review
State permitting documents show Silfab is authorized to store and handle highly reactive substances including hydrogen fluoride, hydrochloric acid and silane, and that the plant must submit a Risk Management Plan to the EPA before bringing regulated chemicals on-site, per the South Carolina Department of Environmental Services. The department's public permit page also outlines requirements for emergency-response coordination, unannounced inspections and air monitoring, the same items investigators say they will be scrutinizing in the current review, according to SCDES. Engineers and hazardous-materials specialists are expected to audit containment tanks, piping and reporting records to pinpoint what went wrong.
What's next for residents
For now, the stop-work directive remains in place while SCDES and the EPA continue their investigations and engineers assess the plant's equipment and safety protocols. Parents and county officials say they plan to demand public briefings and the full results of any independent evaluations before they are comfortable with commissioning resuming, and the attorney general has reserved the right to pursue further action depending on what investigators find. Local coverage has already detailed months of zoning disputes and earlier stop work orders involving the plant.
