But the county road department has added an ancient dust-control product derived from the oil and gas industry.
So-called “fossil water” is pulled from deep underground during oil-and-gas extraction and then treated for use on gravel roads. The water originates from the remnants of ancient seas and swamps that are millions of years old.
“It costs less than mag (magnesium) chloride, and binds better on gravel that doesn’t have a lot of clay,” said road superintendent Rob Englehart. “It is a state-approved product.”
It starts as produced water — natural liquids that accompany oil and gas as it’s drawn up through wells from geologic formations 3,000 to 5,000 feet underground.
The briny water is separated from the oil and gas, and because it is so salty, it’s usually pumped thousands of feet back underground through wastewater injection wells, at least one of which is in Montezuma County.
But the industry found that treated produced water makes a good dust control product, and it received approval from the Colorado Department of Health and Environment. Before it is sold and shipped to counties for spraying on dirt roads, the water goes through a licensed waste-water treatment facility in Naturita run by Reams Construction, according to county officials.
“We’re fortunate we have this option because it reduces our road maintenance costs,” said commissioner Larry Don Suckla.
Besides calcium chloride, the water contains toxic elements, including heavy metals that are filtered out through the water treatment process.
Using a water product linked to heavy industry on county roads has raised some eyebrows. Local resident Ellen Foster questioned the use of fossil water at a recent county commission meeting.
“Calling it fossil water gives the impression that it’s clean, even pristine,” she said. “If it’s going to be sprayed all over the county, I think it is important for the public to understand how it’s treated and if residual contaminants pose a health risk. What is the level of naturally occurring radioactive components?”
Englehart said the use of treated fossil water is permitted and considered safe by the state health and environment department. Road crews have been using it on roads around Lewis, where it binds well to the sandy gravel. It’s also worked well on maintaining the heavily used Dolores-Norwood road. It is not as effective as magnesium chloride on gravel roads with more clay.
“Fossil water is about one-third the cost of mag chloride, but is not ideal for all gravel road conditions,” he said.
The county paid a total of $54,792 for fossil water over the months of May, June and July.