Hold onto your hats: Tomorrow’s Spring Hat Luncheon, a key date on the annual old-school society calendar, will be targeted by opponents of mountaintop-removal coal-mining.

Why’s that, you ask? Well, this year’s Hat Luncheon is co-chaired by Debbie Demchak. She’s married to newly appointed PNC Financial Services CEO William Demchak. And PNC has for years been the target of such protests because it invests in companies that blow the lids off Appalachian mountaintops for the coal inside.

Meanwhile, the Hat Luncheon benefits the city’s parks system — which, as the Pittsburgh Parks Conservancy web page for the event notes, is “a keystone in our city’s status as both ‘livable’ and ‘green.’”

But as the Philadelphia-based Earth Quaker Action Team, which is organizing the protest, puts it, “the Hobet mine in Boone County, W.V., has destroyed the equivalent … of 22 Schenley Parks. Water sources are polluted by mountaintop-removal practices which release heavy metals like arsenic and selenium.”

EQAT, a peaceful, Quaker-led group, organized the April 23 protest at PNC’s annual shareholders’ meeting, held Downtown. The Pittsburgh Post-Gazette reported that protesters shut down that meeting by demanding that PNC get out of the mountaintop-removal business.

PNC is among the nation’s largest financers of mountaintop-removal, according to the Rainforest Action Network.

The Spring Hat Luncheon is set for tomorrow morning, on the Overlook in Schenley Park. EQAT promises “protesters in hats” and more starting at 10:30 a.m.