Michael Bagdes-Canning, 63 and now retired from his career teaching English in Grove City, Pa., on the western side of the state, considers himself "a climate activist," concerned about the pollution caused by the fracking rigs that dot Butler County, where he lives.

So Bagdes-Canning said he was shocked to learn that roughly $2.5 billion of the pension fund that helps pay for his retirement is invested in fossil fuel companies -- including 15 of the 20 firms most frequently cited for health and environmental violations in Pennsylvania.

"In Butler County, we have 17 schools within mile of a fracking pad,  and proximity to a fracking pad is not a good thing," said the retired teacher, citing studies showing people living close to natural-gas drilling sites complaining of a litany of health issues such as headaches and nausea.

This afternoon, Badges-Canning -- his voice fading in and out on a phone call as he traversed the tunnels of the Pennsylvania Turnpike -- and a fellow retired teacher from Butler County were on their way to Harrisburg, where they will plead with the state's Public School Employees' Retirement System (PSERS) to completely divest from fossil fuels.

The group will present PSERS board members with a letter currently signed by more than 200 teachers from across Pennsylvania calling on the massive retirement fund -- which manages roughly $48 billion, give or take, in assets -- to join more than a dozen U.S. cities and scores of universities that have fully or partially divested in fossil fuels, largely because of the impact that burning oil, natural gas and coal has on global warming.

"We can be leaders in the fight for renewables and the move away from fossil fuels," the letter states. "Let's put our money where our values are."

The push comes after Attytood reported in September that PSERS' stake in the company building the controversial Dakota Access pipeline -- the trigger for a dramatic and occasionally violent standoff in North Dakota with the Standing Rock Sioux and their allies -- was $192 million, far more than any other public or quasi-public pension fund. That news -- coupled with images of security guards siccing attack dogs on Native American protesters -- caused some teachers to question the seeming disconnect between teaching kids about the perils of climate change and investing their retirement dollars in fossil fuels.

Since then, activists from Pennsylvanians Against Fracking -- led by Karen Feridun of the anti-fracking group Berks Gas Truth -- have taken a closer look at PSERS investment practices and said they were surprised to learn the full extent of the link between the teacher pension fund and the oil and gas industry.

Their analysis found that more than 1/10th of PSERS assets are invested in individual companies and, of that, almost half, or about $2.68 billion, is invested in energy firms. In fact, their study found PSERS has 232 investments in fossil fuels and only three, totaling just $3.26 million, in so-called "clean energy" such as solar or wind power. Many of these firms drill in Pennsylvania, including 21 of the 35 companies on the powerful Marcellus Shale Coalition, the industry's main state lobbying arm, and, as noted by Bagdes-Canning, some of 15 of the 20 top environmental violators. PSERS officials said they haven't seen the study and can't confirm its accuracy.

Officials with PSERS say the pension system's stance is clear and unyielding: Investments are made for the sole purpose of gaining the best returns for its members.

"Using the System's assets to advance a policy agenda against fossil fuel investments could violate PSERS' fiduciary duty," system spokeswomen Evelyn Williams said in an email. "Historically, PSERS has taken the position that investment and divestment based on moral, political, or social grounds generally violates the board's fiduciary duty."

But teachers like Bagdes-Canning and his fellow Butler County retiree Dianne Arnold -- his carmate for the long. rain-soaked drive to Harrisburg -- see fossil fuels not just as bad morals but a risky investment of their retirement kitty, given the volatility of the world's energy markets.

"If there's a 'carbon bubble', there's a risk of having stranded assets," Arnold told me. She plans to address the PSERS board Wednesday on the economic risks, while Bagdes-Canning said he will tell his personal stories about the negative fallout from the fracking boom on Butler County and how "my (five) grandkids are on the front line."

Bagdes-Canning told me he has a hard time buying the argument that moral considerations have no place. He said one of the two other teachers given permission to address PSERS will ask the board, "Would we be investing in slavery?"

It's not a ridiculous question. PSERS' position suggests that its managers scoured the world for the best place to park teachers' retirement stash, and it just so happened to be a bunch of politically connected firms drilling for gas right here in Pennsylvania. Or maybe, just maybe, PSERS does consider other factors. Other jurisdictions from Washington, D.C., to San Francisco have found it a just cause -- and prudent -- to divest in fossil fuels. As Phillies fans are wont to ask, why can't us?

Bagdes-Canning told me that Wednesday's meeting is just the beginning. "What  we're hoping to do is wear them down. This is only the first meeting. We're planning on coming back and coming back until there's maybe 100,000 names on the letter. We're not going away."