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Originally Posted by SeeGeeWhy
My understanding of the issue with the tight oil/gas boom and "fracking" is that it actually consumes A LOT of water, and let's be honest... the issue isn't the completion method, it is the fact that you're penetrating possibly sensitive groundwater formations above. Cement jobs blow pretty much 85% of the time, so just with the sheer number of wells being put down the probability of future issues just increase.
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85% is a gross exaggeration, but I do agree that not nearly enough resources and money gets put towards good cementing practice.
That said, when it comes to the zone being fractured, the cement bond around that horizon is good probably 99.9% of the time. Why? Because that's where the good expensive cement is, it's where the highest temperature is which is good for the cement transition, and it's the zone that is most adequately cleaned and centralized. Much of the focus is put on that part of the cement job.
It's the uphole secondary zones that are the big issues. The gas-bearing Belly Rivers and the like. Cheap lightweight cement gets placed along those shallower formations and often not a second thought is given to these zones that also require hydraulic isolation. As long as you can frac the primary objective.