A controversial oil drilling process is back in the spotlight this week as state lawmakers are considering a temporary ban on hydraulic fracturing, or fracking.
Even Hollywood has tackled the topic.
In the movie promised land, Matt Damon plays a salesman for a natural gas company, hoping to use the process to extract natural gas from deep underneath a small town.
Fracking involves blasting water, sand and chemicals into deep rock formations to release oil or natural gas.
It's getting a lot of attention as drilling companies look to expand production from one of the country's largest shale oil formations.
"It’s a pretty safe process. It's pretty well understood. It's becoming much more effective now at extracting oil and gas from rock strata and reservoirs that previously couldn't be extracted," explained Bruce Allen, physicist and co-founder of Stop Oil Seeps.
Environmental advocates say there's not enough information on fracking's long-term consequences.
"First and foremost, nobody knows what chemicals are being used and nobody knows where the fracking is being conducted in the state, so essentially its being done with blinders on," said Brian Segee, a staff attorney with the Environmental Defense Center.
Allen argued, "Fracking has been around since 1945, and over 1 million wells have been fracked in the U.S. According to the E.P.A., there have been no confirmed ground water contamination issues."
About two years ago, Santa Barbara County Supervisors unanimously voted to regulate fracking within the county, after a company used the technique in Los Alamos.
"They said 'if fracking is done in our area, we want to know before hand, and we want environmental analysis done.' Santa Barbara County is a leader in that respect. The county has stepped in where the state and federal government have not," said Segee.
California lawmakers are considering temporarily banning the process while studies are done on its effects.
Bills to halt the fracking pending a review of environmental and health impacts have passed their first legislative hurdle.
The Assembly Natural Resources Committee advanced three measures Monday that would prohibit fracking temporarily. The drilling technique involves blasting water, sand and chemicals into deep rock formations to release oil or natural gas.
The bills call for an advisory committee to review health impacts and for lawmakers to approve rules for how fracking can occur.
Environmental advocates say there's too little information on the long-term consequences of hydraulic fracturing. Industry officials cite decades of using the technique in California and elsewhere without any contamination incidents.
"I think putting a moratorium on now is counter-productive, and unnecessary. I think it needs to be carefully regulated and monitored, but I don't think its preventing undue risk," said Allen.
"Rather than have the fracking rush happen, and then find out the problem later, there's a reason to pause, and it’s just a pause, now to get a sense of the impacts," argued Segee.
The measures - AB649, AB1301 and AB1323 - cleared the committee on identical votes of 5-3. Republicans opposed the bills.
State environmental regulators are working on new rules, but they aren't expected to be made final until next year.