In Ask Brock, episode 148, host and drilling trainer Brock Yordy takes a question from Bob, a driller in the southwestern Unites States. He asks about dosing drilling fluids with chlorine to fight back against native bacteria. How much chlorine is just enough to sanitize your drilling project, but not enough that your fluids break down?

“Ten parts per million or 10 milligrams per liter of chlorine is not an issue for many drilling fluids out there, especially NSF-approved sodium bentonite with a PHPA and a PAC,” Yordy says. “It’s not going to be an issue. It’s when we get beyond that 50 parts per million that we start seeing some breakdowns.”

He also discusses makeup water, hardness, chlorides and other topics. Check out today’s episode to hear more.

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