More on fracking - a balanced view

Sent by another reader:- The fracking links post of August 14th open up a can of worms. The links are to Ingraffea - his position at Cornell is 'Professor, Civil and Environmental Engineering' He is anti fracking and has published with Howarth Cornell 'Professor of Ecology and Environmental Biology'
Their work has been challenged (condemned?) by at least 12 other sources - amongst them

May 2011, U.S. Dept. of Energy report: Emissions from natural gas are low compared to other fuels.

•  'Howarth [and Ingraffea] found a large fraction of produced gas from unconventional wells never made it to end users, assumed that all of that gas was vented as methane, and thus concluded that the global warming impacts were huge. As the [Dept. of Energy] work explains, though, 62% of that gas isn't lost at all, it's used to power equipment.'

June 2011, Cornell Univ. Professor Lawrence M. Cathles "Professor of Earth and Atmospheric Sciences"

•  'Ingraffea's and Howarth's analysis is seriously flawed in that they significantly overestimate the fugitive emissions associated with unconventional gas extraction .....' 
• 'The assumptions used by Howarth et al. are inappropriate and ....... their data, which the authors themselves characterize as 'limited', do not support their conclusions'.

April 2011 John Hanger, Head of the Pennsylvania Dept of Env. Protection: -

•  'Professor Howarth's & Ingraffea's conclusion that gas emits more heat trapping gas than carbon, flies in the face of numerous life cycle studies done around the world'.

• 'Professor Howarth & Ingraffea just adopted an extreme and false assumption of no flaring that conveniently moved the result of his life cycle analysis in the direction that he wanted'.

August 2011, Carnegie Mellon Univ. report on life cycle greenhouse gas (GHG) emissions from Marcellus shale production.

• 'The GHG emission estimates shown here for Marcellus gas are similar to current domestic gas.'
• 'For comparison purposes, Marcellus shale gas adds only 3% more emissions to the average conventional gas, which is likely within the uncertainty bounds of the study. Marcellus shale gas has lower GHG emissions relative to coal when used to generate electricity.'
• 'Lead researcher Paula Jaramillo (with reference to Ingraffea and Howarth's paper): 'We don't think they're using credible data and some of the assumptions they're making are biased. And the comparison they make at the end, my biggest problem, is wrong.' 

Cornell organised an internal debate between Cathles and Howarth/Ingraffea over these issues.
I do not think we should publicise one side or the other in this debate. We certainly should not provide a link to a biased source. 
The only defensible link would be to http://www2.epa.gov/hydraulicfracturing
this is the regulatory authority which is currently conducting a 5 year R&D program into the impact of hydraulic fracturing. So far the news flow has not been kind to Professor Ingraffea's position.