By Karl Henkel
State environmental regulators are relatively sure that a brine-injection well in Youngstown hasn’t been the source of six Mahoning Valley earthquakes this year.
But they’re not totally sure.
So to silence any naysayers, the Ohio Department of Natural Resources says it will require Youngstown-based D&L Energy Inc. to backplug its well on Ohio Works Drive if a test determines water is penetrating a deep rock formation.
“We’re going to make them plug that back with cement just to alleviate any of the potential problems,” said Tom Tomastik, geologist at the Ohio Department of Natural Resources. “If we plug that off, then there’s no avenue for the fluid to go down.”
Tomastik said the well will cease operation for the test as soon as another D&L well, permitted in Liberty, is ready to accept brine water.
If the state and D&L determine that brine can enter the Precambrian rock formation roughly 9,000 feet below the ground, D&L will plug the bottom 250 feet of the well with concrete. It is permitted to disperse water in the formations above the Precambrian.
“It will eliminate any perceived accusations,” Tomastik said.
Ben Lupo, president of D&L, said a previous test was inconclusive because debris — most likely iron and muddy water — sits at the bottom of the well.
Injection-well experts previously told The Vindicator that debris is likely from low-salinity, high total-dissolved solids’ brine, which could plug a well.
Aside from quashing the link between possibly injecting brine water into impermeable rock formations, there’s also the question of pressure and the broad effect wells could have on earthquakes.
In the two weeks leading up to the first Valley earthquake in March, D&L increased pressure rates by 225 pounds per square inch, from 1,425 to 1,650, according to documents acquired by The Vindicator.
A typical garden hose exerts water at rate of 50 to 500 psi, depending on structure.
The day after the earthquake, the pressure was lowered to 1,325 psi before it was ramped up to 1,762.5 psi three days later.
A day before the fourth earthquake, on Sept. 2, D&L powered down the well, then started it back up at 1900 psi.
A 2.2-magnitude earthquake happened later that afternoon.
Lupo said pressures are regulated by the state and are safe.
“The state has an equation that they use to have allowable pressures to operate at,” he said.
Currently the D&L Youngstown site is permitted to inject water at 2,500 pounds per square inch.
Reported data covered the first five earthquakes.
The well was debated among geologists and seismologists as to whether it has caused seven Valley earthquakes since March 17 — the first seven ever recorded with epicenters in the Valley.
Six of the earthquakes had epicenters near the well site; the seventh was centered near Hubbard.
Michael Hansen of the Ohio Seismic Network said that to prove a definite link between an injection well and an earthquake, the exact depths of the quakes must be known.
All appear to have occurred 5 kilometers below ground level, about 7,500 feet below the deepest point of the D&L Youngstown well.
Hansen said, however, that to determine precise depths, it is crucial to have at least three seismograph readings for each event.
The only seismograph in the immediate area is at Youngstown State University.
An earthquake as a result of an injection well is not a new phenomenon. Arkansas environmental regulators noticed a sharp decline in earthquakes after four wells ceased operations.