By Ben Geman - 08/08/11 02:25 PM EDT
The letter says current EPA and Energy Department efforts are inadequate to address the practice, which green groups say will lead to widespread drinking-water contamination.
The natural-gas industry calls allegations of contamination inaccurate and says drillers are using necessary safeguards when employing the practice, which involves high-pressure injections of chemicals, water and sand to break apart rock formations and enable trapped gas to flow.
The letter comes several days after a separate environmental group coalition formally petitioned EPA to force new testing of fracking chemicals and other steps under the Toxic Substances Control Act.
Click here to read the new letter to the White House.
Update: The pro-fracking industry group Energy in Depth has posted a detailed rebuttal to the letter, alleging that facts are "painfully absent" from the green groups' claims.
This post was updated at 1:41 p.m.