Driller, public health consultant debate correlation-versus-causation at fracking hearing
Laura Dagley, a medical advocacy coordinator with Physicians for Social Responsibility’s Pennsylvania branch, could not say hydraulic fracturing operations directly cause negative health effects on nearby residents.
But she said it is difficult to ignore the strong correlation that many studies have shown between a fracking operation’s arrival and an increase in negative health effects among people living near a well.
“We know that things like volatile organic compounds and benzene are being emitted by fracking sites, and they cause the same types of symptoms we’re seeing increase near those well sites,” Dagley said.
She testified as an expert witness on public health assessment Wednesday night when the Protect P-T citizen group presented its case at Murrysville council’s public hearing on the Titan well pad, proposed by Monroeville driller Huntley & Huntley Energy Exploration for a property off Bollinger Road.
Dagley talked about something called “the precautionary principle” as it relates to health issues.
“When something is posing a health risk, we should pause that action while we wait for the research on the effects to catch up,” Dagley said.
Physicians for Social Responsibility maintains an online compendium of studies, news stories and materials related to fracking with more than 1,700 entries. More than 80% of those studies “found signs of harm or indication of potential harm” from fracking operations, according to the compendium summary, Dagley said.
Huntley attorney Kate Gafner asserted Dagley was not qualified to be an expert witness, but her argument was rejected by attorney Bill Sittig, who is consulting with the municipality on fracking-related matters. Sittig has been conducting the ongoing public hearing.
Gafner asked several questions prompting Dagley to repeat that she could not show direct causation between fracking and negative health effects.
“Causation is really hard to prove,” Dagley said. “I can’t tell you that someone developed asthma when a well pad came in. But correlation is the first red flag of public health. With any epidemic throughout history, when you’re starting to see a correlation, that’s leading to a problem.
“Once you see causation, that usually means the problem has been around for too long,” she said.
The hearing will be continued at council’s Sept. 4 meeting, set for 7 p.m. at the Murrysville municipal building at 4100 Sardis Road.
Patrick Varine is a Tribune-Review staff writer. You can contact Patrick at 724-850-2862, [email protected] or via Twitter .