UPDATE 5/2: House Bill 1261 gained final passage in the House late Wednesday and was sent to Gov. Jared Polis.
With a cursory stop in the Colorado House, the state Climate Action Plan should be on its way to the governor's desk to become official policy.
The state Senate passed House Bill 1261 with an 18-16 party-line vote Wednesday, sending the bill back to the lower chamber to approve the upper chamber's amendments.
Senators early Tuesday morning tweaked the language in the bill to address disproportionately impacted communities, as well as to grant more credit for technology that reduces emissions, and to instruct regulators to consider how new rules impact electricity reliability.
Republicans continued to warn that the goals to reduce greenhouse gas emissions would cost the state's economy and residents at levels that aren't known.
"There are no free lunches," proclaimed Sen. Jerry Sonnenberg, R-Sterling, on the Senate floor Wednesday.
The bill says the state should create policies that reduce emissions by at least 26% by 2025, at least 50% by 2030 and 90% by 2050, based on 2005 levels.
The state Air Quality Control Commission would be tasked with creating unspecified rules to help the state meet those goals.
Sen. Ray Scott, R-Grand Junction, said the bill "should create concern for all the folks in Colorado."
He said he understood its intent, but he thought it was laden with uncertainties.
"I think there's a lot of confusion about what this may do to the future," Scott said.
With just two days left in the session, the bill will be a high priority when it returns to the House, where it was introduced by House Speaker KC Becker, D-Boulder, on March 21.
Sen. Larry Crowder, R-Alamosa, said Colorado acting independently won't remedy climate change, though it could be "devastating" to jobs and communities.
"If we think we can have an impact by having Colorado carved out as to make it a Utopian world, I don't think that quite works," he said.
Sen. Bob Rankin, R-Carbondale, said the bill gives a lot of authority to the Air Quality Control Commission to adopt "aspirational" goals.
"I'm asking for a no vote on the bill, but I'm how do we implement the next steps in the bill."
As Republican senators pounded away at the bill on the floor, Democratic lawmakers stayed on the sideline, since they had the votes to pass it, but spoke out on Twitter.
"The cost of inaction is great!" tweeted Sen. Angela Williams, D-Denver, one of the bill's sponsors. "Climate change is the most pressing environmental challenge of our time."
Sen. Owen Hill, R-Colorado Springs, said more work on the plan is needed.
"The reality is all they talk about is the benefits and the goals, but very few proponents will be honest about the costs," Hill said.
Environmental groups have celebrated the progress on the issue.
"Our state is on the front lines of climate change and Coloradans agree we must act," Kelly Nordini, executive director of Conservation Colorado, the state's largest environmental organization, said in a statement Wednesday.
"Thank you to our state senators who prioritized climate action today and voted to pass HB 19-1261, the Climate Action Plan."