States do a fine job of regulating the drilling process of "fracking," and transferring that regulatory authority to the federal government is not necessary, according, to West Virginia oil and natural gas industry executives.

Identical bills were introduced into the U.S. House of Representatives and Senate this summer to repeal a portion of the Safe Drinking Water Act that exempts hydraulic fracturing operations from that act.

Fracking, as it is known in the drilling industry, is a process that injects treated water deep into the productive zone of natural gas and oil wells to fracture the rock and stimulate more production of gas or oil. The procedure has been a common practice in the industry since the 1940s and is used to enhance production from new and older wells.

Senate Bill 1215 and HR 2766 are known as the FRAC Act -- Fracturing Responsibility and Awareness of Chemicals -- and would amend the Safe Drinking Water Act to repeal an exemption for hydraulic fracturing operations.

In effect, the bill would transfer regulatory responsibility from state agencies to the U.S. Environmental Protection Agency. The legislation also would require companies to disclose the chemicals they use in hydraulic fracturing operations.

While fracking is used throughout the industry, the process is especially important to production of gas and oil from tight sand formations, such as the Marcellus shale, where grains of sand are compacted tighter than in formations where gas and oil have traditionally been extracted.

The Marcellus shale formation is considered by geologists to be a "super-giant natural gas field" that underlies much of northern West Virginia, eastern Ohio most of Pennsylvania, and southern New York.

U.S. Sen. Robert P. Casey, D-Pa., is one of the bill's sponsors.

"Drilling for natural gas in the Marcellus shale across much of Pennsylvania is part of our future," Casey said. "I believe that we have an obligation to develop that natural gas responsibly to safeguard the drinking water wells used by 3 million Pennsylvanians."

But some in the drilling industry say the danger to groundwater stated by the bill's proponents are overstated.

"In a word, it's ludicrous," said Greg Kozera, regional sales manager for Indiana, Pa.-based Superior Well Services, when asked about the proposal. He said there is no danger of frac fluids injected into natural gas wells getting into water supplies.

Most drinking water is from the top 200 or 300 feet from the ground's surface while frac jobs for conventional wells inject water about 1,000 feet below the surface. Wells in the Marcellus formation drill deeper, injecting frac water at 7,000 to 8,000 feet.

"When we are pumping at 8,000 feet, how difficult is it for a fracture to grow from 8,000 feet to the surface? That would go through solid rock. It's virtually impossible," Kozera said.

As for the chemically treated frac water that flows back to the surface of the well, Kozera said that water is cleaned and either reused for fracking or discharged after being treated. Frac fluid is 99.51 percent fresh water and sand, while the remaining half a percent includes chemical additives to support the hydraulic fracturing process, according to a Web site by Energy in Depth, a consortium of small independent oil and natural gas producers (www.energyindepth.org).

"When that water comes back, it's captured either in tanks or lined pits, and often it's being reused," Kozera said. "The states have very strict requirements on discharge. It goes to a treatment facility. If anything is discharged, it's all within the specs of the Clean Water Act. As I see it, this is a nonissue."

Charlie Burd, executive director of the Independent Oil & Gas Association of West Virginia, also said the proposed legislation is unnecessary.

"Every year across the United States, thousands of oil and natural gas wells are hydraulically fracked. Not one of these treatments has been reported to pollute any freshwater aquifers," Burd said in an e-mail.

"Oil and natural gas exploration and production companies spend large sums of money in the well construction process to ensure the safety and integrity of freshwater aquifers. It is also vitally important to understand that after the completion of the fracturing treatment the injected fluid is flowed back under very controlled and calculated conditions then disposed of in an U.S. EPA approved facility."

Besides their belief that stricter legislation is not necessary, both Kozera and Burd questioned the need for federal regulators to take over review of what traditionally has been a state regulatory responsibility.

"There have been many technical articles written and presented to show that hydraulic fracturing is a safe, efficient and cost-effective method to extract oil and natural gas for our country's energy needs without causing environmental harm," Burd said. "State governments in the oil and natural gas-producing states have long recognized this and have crafted appropriate regulations to govern the exploration of oil and natural gas in an environmentally safe manner."

Added Kozera: "The states do a pretty darn good job of regulating this and other industries. If you step over the line, they'll whack you. The regulations are there, and the states enforce them well."

Both Kozera and Burd bring up energy security in their arguments to maintain state regulation over fracking operations.

The Senate bill has been referred to the Environment and Public Works Committee. The House bill is sponsored by Colorado Democrat Diana DeGette and has been referred to the House Energy & Commerce Committee. Both bills have several co-sponsors, including representatives from New York and Pennsylvania, which are natural gas-producing states.