In order to illustrate how fracking works, jets shoot fracking fluid, which is a mixture of sand, water, and hundreds of chemicals, into the drilled hole to create cracks in the shale. The fracking fluid breaks down the shale releasing the oil, which gets pumped back up to be treated. Most of the fracking chemicals are undisclosed by fracking companies and could be potentially harmful; can be performed in a vertical oil well, as well as into shale and tar sands (Walsh). When mining deeper oil sands, a different approach is used that is similar to fracking. This method is known as steam-assisted gravity drainage, also known as SAGD. SAGD entails two horizontal drills creating wells on top of each other. As well as a highly pressurized steam
