* Gov't crafting rules for shale drilling on public lands
* Opponents of shale drilling use "scare tactics"-lawmaker
* Interior trying to support shale development-Salazar
(Adds Salazar's comments on water contamination, EPA)
WASHINGTON, Nov 16 (Reuters) - U.S. Republicans on Wednesday blasted the Obama administration's plans to expand regulation of the controversial "fracking" drilling practice essential to tapping the nation's abundant shale oil and gas reserves.
The Interior Department is in the process of updating rules for hydraulic fracturing on public lands and developing a proposal to require disclosure of chemicals used in the drilling technique. [ID:nN1E79U0TY]
Republicans at a House Natural Resources committee hearing on Wednesday raised concerns that onerous regulations on "fracking" could limit the development of the resource.
During a tense exchange between Republican Congressman Louie Gohmert and Interior Secretary Ken Salazar, Gohmert said much of the opposition to fracking seems to be based on "scare tactics."
Gohmert challenged Salazar to name a scientific study that proved that fracking had contaminated drinking water.
"You have no scientific studies that show that it does that," Gohmert said.
Salazar later clarified that while Interior is not aware of any contamination from the actual process of fracking, there have been instances of water contamination from oil and gas wells.
"We do not know of any examples of that on public lands, but it demonstrates the importance of making sure that we have well bore integrity up and down the entire well bore, including following the hydraulic fracking operations," Salazar told reporters after the hearing.
Innovations in hydraulic fracturing, which involves injecting water and chemicals into shale formations to extract oil and gas, have spurred a shale drilling boom in the United States.
But the expansion of shale development has led to backlash from environmental groups and landowners near shale drilling operations, who complain that the practice is polluting the water and air.
"Our program we're putting on the table is not meant to impede shale gas, it's meant to support shale gas," Salazar said.
Salazar said the administration is attempting to address public concerns about fracking before the opposition curtails the practice.
The U.S. Environmental Protection Agency also plans to regulate some aspects of fracking. Last month it said it will propose standards on wastewater discharged from natural gas extraction by 2014. [ID:nN1E79J1U9]
James Hanlon, the director of wastewater management at the EPA, said at another congressional hearing on Wednesday that concern has been raised in Pennsylvania about the handling of wastewater. The availability of sites there to re-inject wastewater into the ground is not as abundant as it is in Texas and Oklahoma.
But industry and state government representatives within natural gas producing states said they have done a good job of regulating fracking themselves and they are wary of federal regulations.
Tom Stewart, the executive vice president of the Ohio Oil and Gas Association, said minimal federal standards on fracking water would be a problem because the geography and geology of every fracking state varies highly.
(Reporting by Ayesha Rascoe; Editing by Marguerita Choy and Bob Burgdorfer)