A bill that would ban future oil and gas development in Nevada has passed a committee vote in a small but significant victory for California billionaire environmentalist Tom Steyer.

The bill, AB 159, passed the Nevada Assembly’s Natural Resources, Agriculture and Mining Committee on April 6, according to the Las Vegas Review Journal. Seven Democrats supported the bill and four Republicans opposed it in a party-line vote.

With help from the California billionaire, Democrats won back control of the Assembly and the Nevada Senate in last year’s election, after two years of Republican majorities. As Western Wire has previously reported, Steyer and his wife, Kat Taylor, personally contributed $70,000 to Democrats running in key state legislative races. The lead sponsor of the bill to ban hydraulic fracturing  – an essential technology for developing oil and natural gas – is Assemblyman Justin Watkins (D), one of Steyer’s favored candidates.

Steyer has called for a ban on hydraulic fracturing, or “fracking,” in his home state of California. He is also a major donor and a key ally to “keep it in the ground” groups like 350.org and the Sierra Club, which have campaigned for national, state and local-level bans on oil and gas development for years.

In committee, AB 159 was amended to allow a handful of oil and gas companies to keep their existing permits, issued under a law that passed the state legislature in 2013. The legislature was also controlled by Democrats in 2013, and the pro-fracking law passed by Democrats was approved by the Assembly 41-0 and by the Senate 21-0. It was signed into law by Gov. Brian Sandoval (R), who is now serving his second and final term. Democratic proposals to ban hydraulic fracturing in Nevada surfaced after Steyer got involved in last year’s state legislative elections.

Nevada has not historically produced much oil and gas, but with the help of modern technologies, the state’s geology holds some promise. To date, only a handful of exploratory wells have been drilled. Republicans in the natural resources committee said they opposed AB 159, even with amendments that dealt with existing permits, because a hydraulic fracturing ban isn’t supported by the experience of oil and gas-producing states.

“I think we are saying no to an industry we don’t understand,” Assemblywoman Robin Titus (R) told the Review Journal.

Watkins, lead sponsor of the bill to ban hydraulic fracturing, claims the technology is unsafe. But state regulators have rejected his argument and similar claims have been consistently debunked over the years, even by senior members of the Obama administration.

Ken Salazar, President Barack Obama’s first Interior Secretary, warned against the “hysteria” surrounding hydraulic fracturing, which “has been done safely hundreds of thousands of times.” Gina McCarthy, who led the U.S. Environmental Protection Agency during Obama’s second term, said there is “nothing inherently dangerous in fracking that sound engineering practices can’t accomplish.”

Sally Jewell, who served on the board of a national environmental group before becoming Obama’s second Interior Secretary, said “fracking has been done safely for many, many years.” Jewell also said fracking bans are “the wrong way to go” and activists who push for state and local prohibitions “don’t understand the science behind it.” Much earlier in the Obama administration, a joint report from the U.S. Department of Energy and the Ground Water Protection Council concluded hydraulic fracturing was “safe and effective.”

Despite last week’s committee vote, the bill to ban hydraulic fracturing still faces major hurdles. Besides Gov. Sandoval, who will remain in office until early 2019, not all Democrats have changed their minds about natural resource development, according to Ray Bacon, executive director of the Nevada Manufacturers Association. “I think it was dictated from afar that we needed an anti-fracking bill because Democrats have control, but I’m not sure that there’s any passion about doing the thing,” Bacon told Western Wire last month.