Under 3, not worth reporting, but there is a neat news article.
This has a 'minute video', which might be the way those 'Minute Earth' people are finally making money. As usual, they have it all wrong, but this is the NY times we're talking about. :)
These injection wells are all 25,000 barrels a day monsters straight into the faults. Natural infiltration controlled New Madrid, Tennessee, and Toronto. The wells are probably 2 orders of magnitude greater. I say it needs a 7 to get them to stop. :)