Is that the same bedrock they drill through?

That is only a meaningful question when you are talking about cases where the place they are drilling is directly through an aquifer, or am I misunderstanding your question? Drilling through aquifers does happen, and it's been a while since I've taken geology, but I don't think they are always drilling through aquifers. And anyway, it's my understanding that the procedures for safely drilling through aquifers are well documented and pretty thoroughly regulated (here's some info on the procedures of drilling through aquifers). If you are privy to a way these procedures are not safe, that conversation is certainly worth having, but let's talk about that, not fruitlessly being married to the notion that fracking is bad. There are risks, obviously. The environmental risk of spilling a tanker of maple syrup is significant in the case of spill, but that means we need to transport maple syrup more safely, not ban maple syrup.

Anyway, what I'm getting at is that snidely asking "is that the same bedrock...?" seems like more of an attempt to knock me down a peg, rather than a real concern about the risks of fracking to the environment. Not to say you are insincere, but that kind of question just seems aimed to frustrate me, and it doesn't seem to aid a sincere conversation about determining the risks.

That's objectively untrue. They only recover what's easiest to get back out, but all drilling sites leave plenty of their fluid down there since there's no way to extract it all back out. If you're going to downplay something, at least try to steer clear of blatant lies.

First of all, I apologize if it seems as though I meant 100% of lubricants and water are removed. I am aware that a small amount remains, along with the sand that the water and lubricants are paving the way for—the sand being the operant material that props open fissures to make way for the gas to be extracted. But I have never seen much of any indication that the leftover material is a significant amount, and furthermore it is my understanding that these lubricants and water are fairly harmless, if they somehow were to make it back across the fracked fissures, up the kilometers deep well and into an aquifer.

That said, do you have a source on this? I'm not "blatantly lying." I suppose I could be mistaken, but it is my understanding that gas cannot actually be extracted until the fracking fluids are removed.