The Department of Conservation recently released draft regulations for energy companies that inject chemicals into the ground under pressure to release oil.
The regulations would require companies to identify those chemicals unless they are considered trade secrets.
Some lawmakers say the regulations aren't tough enough to protect public health and water quality.
Democratic Senator Fran Pavley Chairs the Committee on Natural Resources and Water.
"This is the beginning of the discussions," says Pavley. "The proposed draft regulations in my opinion have had several gaps in them and we'll be sort of trying to probe and discuss those with them."
Tupper Hull, with the Western States Petroleum Association, disagrees.
"We think state of California is on the right track in creating a framework that provides the public confidence this technology is safe and a complete understanding of about what chemicals are being used, but still maintains the very important protections for trade secrets," says Hull.
One environmental group is suing the state for allowing fracking to expand without what it claims is legally required oversight.
Regulators, environmentalists and representatives of the oil industry are scheduled to testify.