Brine is just salty water.

The brine commonly spread on dusty roads to knock down dust is salty water that comes out of the ground as part of oil and gas production.

“Brine is ancient ocean water,” according to Arthur Stewart of Cameron Energy.

“We are tapping oil found in sandstone formations — the sandstone layers are ancient ocean beaches,” Stewart said. “Because the sandstone formations are old beaches, there is also trapped therein old ocean water.”

Developers find oil and gas in the sandstone.

It migrates there from lower, shale layers and stays because of impermeable layers above, he said.

As the developers extract the oil and gas, they also get the brine.

It is not fracture water nor flowback.

“Flowback is the water that literally ‘flows back’ immediately after hydrofracturing a well,” Stewart said. “Contained in the flowback would be some of the material that an operator uses to hydrofracture the well.”

Unconventional — Marcellus and Utica shale — well operators “use a variety of chemicals” in fracturing the shale because the shale is less porous and harder to fracture, Stewart said. “We do not use the variety of chemicals used in shale wells… we are tapping sandstone formations which are easier to fracture and produce from.”

But flowback is not what operators were putting on roads.

“The brine we local producers are generating — and which has been used on township roads in our area for decades — is not fracture water, it is old ocean water,” he said.

“Municipalities have been using oil and gas brine as a dust suppressant for decades,” Stewart said. “We oil and gas producers provide it to them, usually for free, making it very efficient for townships.”

He said complaints about brine use for dust suppression “are founded on something other than good science. The DEP permitted brine spreading for decades. The DEP has a recently completed study that shows negligible impact.”

The impacts of road dust on human health, particularly respiratory system problems, have been studied.

“There are, of course, a host of health problems –let alone nuisance problems — yielded by dust from unpaved roads,” Stewart said. “If brine is not used, a very common alternative product is kerosene.”