A benefit of the incredible focus on gas drilling and fracking is greater and long overdue attention to the quality of water in private water wells. And as the facts are gathered about what has been and is in water wells before any drilling is done, the compelling need to clean up private water wells is documented.
In this vein, USGS did a major study of methane levels in New York water wells. The results are striking, including the literally explosive finding that 2% of the wells tested (200) had ignitable levels of methane in them.
Also 9% of the wells had methane readings above the Office of Surface Minining's action level of 10 mg/L. A full 53% of the water wells had detectable levels of methane, and 47% did not. The report's links are:
http://www.usgs.gov/newsroom/article.asp?ID=3391#.UFIa5FHGx8F; and http://pubs.usgs.gov/of/2012/1162/pdf/ofr2012-1162_508_09072012.pdf.
To be clear, the USGS findings of methane in New York water wells are pre-gas drilling and have nothing to do with gas drilling. The conclusion that 2% of NY water wells have combustible levels of methane and that 9% have levels above the federal action level is serious and should trigger a major effort to clean up private water wells, whether or not drilling takes place.