Environmentalist activists proposed carbon emissions regulations to the state Environmental Quality Board Wednesday that would, if implemented, create a market for greenhouse gases to reach carbon neutrality by 2052.

Their argument cites both existing state clean air laws as well as the environmental rights clause of the state constitution to claim the state has a duty to reduce greenhouse gas emissions to protect its residents from harm.

“I not only think it’s feasible, think it's absolutely essential,” Joseph Otis Minott, executive director of the Clean Air Council, said. “We’re prepared to litigate it if need be. This is the right path for Pennsylvania.”

Amid excavators and hard hats on a dug up Greenfield Street, Pittsburgh Mayor Bill Peduto struck an optimistic tone on replacing the lead pipes that have shaped the city’s water politics since 2016.

Citing a drilling slowdown amid continued fixed costs, the state Department of Environmental Protection proposed increasing the cost of unconventional gas well permits by 150 percent, to the cries of the industry and legislative allies.

Set in 2014, the permit for the unconventional natural gas wells used in fracking currently costs $5,000. However, under the proposed increase, the permit’s cost would increase to $12,500 — which industry allies claim would be the highest in the country.

A hearing on an amended, omnibus environmental bill, which includes a nitrogen procurement plan to ease waterway pollution, brought up questions of funding and interbranch cooperation Thursday.

The House Environmental Resources and Energy Committee heard testimony on the bill, SB 799 by Sen. Richard Alloway (R-Franklin). Originally, the bill only set up a procurement program to use public dollars to purchase nitrogen credits from the agricultural industry to keep runoff from heading into the commonwealth’s streams and rivers and into the Chesapeake Bay.

Then, in late January, the Senate amended the bill to include a reauthorization of the Growing Greener program, first set up under former Republican Gov. Tom Ridge in 1999.

Legal wrangling over the flashpoint Mariner East 2 piepline’s permitting was finally resolved Friday, as the Department of Environmental Protection announced it had reached a settlement with suing environmental groups.

The Philadelphia-based Clean Air Council, as well as two other state environmental groups, had originally sued the commonwealth’s main environmental regulatory agency in February 2017, claiming that DEP had issued permits off of incomplete applications.