Both houses of Congress this week passed legislation President Obama is expected to sign that "formally urges the U.S. Environmental Protection Agency to conduct a new study on the risks that hydraulic fracturing poses to drinking water supplies.

Chemicals that recently showed up in Wyoming drinking water are believed to be byproducts of hydrofracking.Environmental Protection Agency Administrator Lisa Jackson has said publicly she believes this should be done.  A 2004 EPA study of the practice "is widely considered to be flawed" because, among other issues, "data was selectively collected from sources that had a vested interest in the oil and gas industry, while other relevant information was ignored," said U.S. Rep. Maurice Hinchey, who represents the Hudson Valley.

Meanwhile, U.S. Sens. Kirsten Gillibrand and Bob Casey have introduced legislation - the Fracturing Responsibility and Awareness of Chemicals Act.  The FRAC Act would repeal a Bush administration exemption provided for the oil and gas industry, and would require it to disclose the chemicals used in hydraulic fracturing processes, Gillibrand said. Currently, the oil and gas industry is the only one exempted from complying with the federal Safe Drinking Water Act.