As damaging algae blooms continue to afflict Florida, the state is taking steps to crack down on and track pollution from biosolids, the waste from sewage plants loaded with nutrients that can fuel blooms.
But the new rules, conservationists warn, continue to ignore a loophole for about 40% of the state’s waste.
At a final hearing last week, state environmental regulators said the new rules address two classes of sludge largely used in agriculture. Class AA, a third class, gets more highly treated to remove pathogens and heavy metals and is classified as a fertilizer not covered by the rules.
But environmentalists warn Class AA still contains phosphorus and nitrogen that feed blooms. Not including the class, they say, creates a gap in tackling worsening blooms that have increasingly fouled Florida waters and fueled saltwater blooms moving inshore.
“Class AA should no longer be exempt,” the Everglades Coalition wrote on behalf of more than 60 environmental groups statewide, when the rules were first proposed.
The state began developing the new rules in 2018 but tabled the effort in 2020 after Gov. Ron DeSantis convened a blue green algae task force to come up with ways to address the state’s worsening water quality. Among the recommendations was better monitoring to detect the source of damaging nutrients.
About 130 sites statewide use the less treated biosolids, Class A and B, mostly on pasture and hay crops, said Maurice Barker, chief of the state’s wastewater management program. The new rules would expand limits on where and when those biosolids can be applied to protect lakes, rivers, springs, well fields and other water supplies. The rules also increase monitoring to get a better handle on the supply of nutrients driving blooms.
With the new restrictions, Barker said the amount of land where biosolids are used will need to increase by up to 10 times to keep up with the increasing amount of biosolids statewide sewage plants are producing.
Environmentalists applauded tightening rules and improving monitoring. But they say omitting Class AA leaves a hole in the data. They also worry more sewage plants will switch production from the less treated biosolids to Class AA to avoid the new limits, something Barker said the state anticipates.
“We're expecting the application rates to drop significantly. And if the application rates drop, more land is going to have to be permitted to apply those biosolids,” he said.
That means transportation costs will likely rise, he said.
“So you're going to have longer hauling distances,” he said. “We do expect some facilities to shift to producing Class AA biosolids so they'll have the capital cost to cover transportation costs."
Environmentalists say the state needs to apply the same standards to all biosolids, including application limits, plans for managing nutrients, soil and groundwater monitoring and site logs where biosolids are spread.
“These kinds of changes will help us determine more accurately whether this class of biosolids is influencing harmful algal blooms,” said Laura Reynolds, who was representing the Izaak Walton League at the hearing. “It will also tell us where the nutrients are coming from. We think this is a major portion of our problem statewide."
The new rules are open for public comment through June 10 and are awaiting approval from Gov. Ron DeSantis. To submit comments, email Maurice.Barker@FloridaDEP.gov
Copyright 2021 WLRN 91.3 FM. To see more, visit WLRN 91.3 FM.