"The roads were paved with gold" is a common way of saying a given town was overflowing with wealth. Things must not be going so well in Florida, though, since the state is considering paving roads with radioactive industrial waste instead.
As reported by NPR, the material in question is phosphogypsum. The byproduct of fertilizer production using phosphate rock is usually stored indefinitely due to its weak radioactivity. This is because the largely gypsum-based material contains naturally-occurring uranium and thorium, along with their breakdown products radium, radon, and polonium. Extracting the radioactive content is economically prohibitive, so most phosphogypsum goes unused.
Florida lawmakers want to change all that and use the material as a feedstock for road construction. Bill HB1191 has been sent to Governor Ron DeSantis for approval. It would compel the Florida Transportation Department to explore the use of phosphogypsum in road paving, through the development of demonstration projects including the material. Phosphogypsum would then potentially be used as an aggregate material to build roads in much the same way as gravel, sand, or crushed stone. The bill sets a deadline of April 1, 2024, for action by the department.
Multiple health concerns exist around phosphogypsum, particularly in its use as a road construction material. The radioactive material involved emits alpha particles, which while lacking penetration of other radioactive emissions, can pose a risk to health if ingested. Large dusty piles of construction material could thus potentially expose workers and bystanders to a higher-than-expected dose of radiation. Radium in the material can also decay into radon gas, which is known to cause cancer through exposure.
Critics of the move are urging the governor to veto the bill. "Using radioactive phosphogypsum in roads is not a solution to the fertilizer industry's toxic waste problem," read a letter signed by the Center for Biological Diversity and over 30 other groups. Beyond direct exposures, there are also concerns that the material could contaminate groundwater over time.
Certain Florida lawmakers and the Fertilizer Institute contend that potential doses to the public would be below baseline levels. It bears noting that both may have a vested interest. Florida currently has approximately a billion tons of radioactive phosphogypsum stored across 25 stacks, with 30 million tons added every year.
Getting phosphogypsum approved for use in road construction has long been a goal of the fertilizer industry. Instead of a waste product that currently costs money to store, it would turn phosphogypsum into a saleable material in demand. The EPA tentatively approved the material for road construction in 2020 under the Trump administration, after requests by industry lobby group The Fertilizer Institute. However, this approval was later rescinded in 2021 in part due to pressure from environmental groups.
DeSantis could sign the bill into law at any moment; if he takes no action, the bill will be automatically enacted. Notably, though, the EPA's disapproval technically blocks Florida from using phosphogypsum in this manner. According to the federal regulator, the state would have to apply for approval to use the material in road construction. This would involve the EPA opening up the matter to public comment and running its own analysis of the proposal.
Whether Florida rolls out radioactive roads is yet to be seen. If it does, expect a million YouTube videos from science buffs waving Geiger counters around over freshly-laid tarmac. In any case, it's probably not a great time to start a new career as a road builder in the state of Florida if you're squeamish about radiation exposure. Worth a thought.
Got a tip? Let the author know: email@example.com