The Rising Influence of Rising Affluence

[OakesCS]

Gary,
it's quite likely that injection is linked to the small earthquakes near the injection sites in Ohio. Various industries have been injecting liquid wastes in Ohio for many decades (it goes back to at least the 1960s). Connection between injection and earthquakes in Ohio is traceable back to at least 1987, c.f. http://bssa.geoscienceworld.org/content/94/1/76.short

If there is a more frequent occurrence of injection related earthquakes, then i wouldn't be surprised if it's related to a higher volume of injectant related to shale gas hydrofracturing. The problem is not necessarily due to the act of injecting but rather attempting to inject too much volume too rapidly. That causes a pressure buildup in the formation and fractures the rock or may reactivate previously existing fractures (aka faults). It's the same phenomenon as hydrofracturing but without the intent or control.

I believe that the general practice is for the gas/oil production companies to farm out the waste disposal to 3rd parties. That is a much lower margin business and i suspect the assessment of the geology and injectivity of the disposal reservoirs receives a lower level of scrutiny than oil and gas bearing formations. I also suspect the disposal companies compete on a volume basis to make up for the lower margins. Unfortunately, Mother Earth doesn't care so much about the business model.

If it makes you feel better, the trend is toward reprocessing and recovering as much of the water as possible for hydrofracturing other wells. That still leaves some garbage but it reduces the earthquake problem.
cheers,
Charlie