Each of the 260 orphaned wells will cost an average of $80,000 to clean up.
John Hickenlooper on Tuesday told state regulators to try to have California-style low-emission vehicle standards in place by the end of the year.
The executive order was spurred by a rally at the capitol from progressive groups and elected officials.
Critics called for lawmakers to explore all options to pass at least some bills — including calling themselves back for a special session.
One killed bill would have allowed the use of medical marijuana to treat autism spectrum disorders.
School nurses will be able to administer medical marijuana to students, but cannabis tasting rooms won't be opening anytime soon.
Gov. Hickenlooper said Colorado will “take seriously the Court’s admonition that the state must apply its laws and regulations in a manner that is neutral toward religion."
The two other bills would have allowed out-of-state landowners to vote in Colorado elections and lowered the cost of some tobacco products for out-of-state customers.
Colorado was awarded the 1976 Winter Olympics, but later said “no thanks” and the games went to Innsbruck, Austria, instead.
Hickenlooper has stated in the past that mineral rights are personal property and that bans are a "taking." Longmont's approach may finally sidestep that issue.