ORANGE PARK – Operator error at an Orange Park wastewater treatment facility led to the discharge of more than 65,000 gallons of partially treated wastewater into the St. Johns River Sept. 28.

The water at the Miller Street Wastewater Treatment Plant had only been treated biologically by the time it was discharged. An on-call operator failed to answer three alert calls from the wastewater treatment system shortly after midnight.

Typically, wastewater is first treated biologically by microorganisms, then filtered and treated with chlorine. The alert sent to the on-call employee overnight directed the employee to switch from an empty chlorine tank.

“The person on call received three calls from our answering service then fell back to sleep,” said Dennis Martin, wastewater superintendent with the Clay County Utility Authority. “Since he failed to respond, there was no other alarms and the chlorine depleted out and when the day shift came in, the chief operator noticed it was in alarm position.”

When the tanks were not switched, the chlorine feed failed and the system automatically discharged partiality treated water into the St. Johns River.

The 65,052 gallons of wastewater likely contain high levels of fecal coliform, a bacteria that originates in the intestines of warm-blooded animals that is typically a primary indicator of potability.

Treated water is not potable – or safe to drink – but high levels of fecal coliform can be unsafe to humans and marine life. Chlorine, likewise, endangers marine wildlife.

CCUA discharges water daily to the St. Johns River depending on the current demand for treated water. Officials typically reserve wastewater for agriculture. If the demand isn’t there, the chlorine is removed from the water and the water is discharged into the river normally.

At low tide, the Miller Street plant discharges water about 800 feet off the banks of River Road from a pipe roughly 10 feet under the surface, according to Martin.

Martin said it had been years since the last time a similar event occurred at the utility. The employee in question has since been reprimanded and suspended from work for the time being.

Although events like these are relatively rare, this event coupled with the myriad of toxins, runoff and pollution dumped into the river as an after effect of Hurricane Irma has conservationists worried about the health of the river.

“There’s a lot of contamination in the river because we’re downstream from the 100 miles of waterways and everything drains into the St. Johns,” said St. Johns Riverkeeper Lisa Rinaman. “Everything flooded during the storm. There’s agricultural runoff, storm water pumps from industrial sites…it’s just sort of a contaminated soup out there and we have to show extreme caution.”

The impacts of Irma, while immediately evident throughout the state, may show themselves further down the line, Rinaman said. Flooding caused septic tanks to leak sewage and fertilizer into the St. Johns River as well.

Rinaman also showed concern for superfund sites near the river and the runoff that could have washed into the St. Johns. According to the Environmental Protection Agency, there are two superfund cleanup sites along the St. Johns River.

Nutrient pollution, like those that come from lawn runoff and untreated water, can exacerbate the emergence of toxic algae blooms.

Residents who see any sort of oil slick on the water’s surface or thick, green algae are advised to report it to the Department of Environmental Protection for testing.

“Just have extreme caution,” she said. “Now is not the time to go tubing on the river.”

For those with more questions, Orange Park Town Council Member Connie Thomas is holding a roundtable discussion Friday, Oct. 6 in the council chambers. The discussion will include a representative from the DEP and will examine issues surrounding local waterways after Hurricane Irma.