No matter how hard they don’t try . . .
Have skimmed the progress report of the EPA’s study of the impact of fracking on water resources, copy here : http://www.epa.gov/hfstudy/pdfs/hf-report20121214.pdf And I noticed a few curious things, like the fact that the EPA apparently do not know much about gas wells, which is not too surprising, considering they were fracked out of regulatory oversight over oil and gas wells back in 2005 by the Halliburton Loophole. Take for instance this chart on page 17 which purports to show the difference between a horizontal gas well on the left, and a vertical gas well on the right. The bias is obvious in the illustrations, to wit:
“Horizontal wells do not encounter any gas deposits near the surface, and the shale is far away from water bearing strata. No water wells are located near horizontal wells.”
Take a look at this rather rosy hydrologic scenario for horizontal wells:
Shale gas is the source rock of all oil and gas deposits – so, vertical wells are tapping “traps” and “pools” of oil and gas that originated below them in shale. Which means that, in most places where horizontal shale wells are drilled, there already are vertical wells above the shale. Whatever conditions you encounter with vertical wells – such as the shallow gas deposits shown on the right, shown at 1,000 feet to 2,200 feet, you will encounter (and drill through) in a horizontal well, with gas shown at 7,000 feet – below the vertical wells. The shallow gas deposits don’t disappear above shale gas, in fact, it’s almost certain they will be there – ready for horizontal shale gas wells to ventilate them upwards into groundwater.
And all horizontal wells aren’t that deep or separated sufficiently from water bearing strata. In fact the ones that gassed aquifer in Pavilion, Wyoming were fairly shallow, which is why the frack went into them. And as Lou points out:
“In NY State much of the shale is less than 5000 feet deep and the proposed regulations would allow HVHF in horizontal wells only 2000 feet deep or 1000 feet below the deepest aquifer, which ever is deeper.”
Meaning close enough for the frack to go out of zone, hit a fault and gas the aquifer above it. This is what happened recently in Alberta, a fracker fracked an aquifer.
Still, the main source of most methane migration into groundwater is from shallow gas deposits – as shown on the vertical well illustration, but conspicuously absent in the horizontal well, where they should be shown between the shale and the groundwater – and venting gas up the well bore like this:
The EPA says they are looking for sources of contamination, “that may lead to changes in local drinking water resources, including well construction failure and induced fractures intersecting existing natural (e.g., faults or fractures) or man-made (e.g., abandoned wells) features that may act as conduits for contaminant transport. “
What they are apparently not looking for is the most common source of methane migration – the aging well bore itself, not just abandoned wells, but new wells aging badly. Which has little to do with how they were drilled, well construction or fracking techniques and much to do with the inability of the cement in the well to prevent methane from shallow deposits venting up the well.
This phenomena is one of the most common sources of water pollution from gas wells. It is also the one that the industry does not want to talk about. Nor, apparently, does the EPA.
Horizontal wells are 4 times more likely to vent methane than vertical wells. Is the EPA looking into this ? Evidently not. Because it might conclude that horizontal well bores are particularly capable of channeling gas into groundwater – due to their large circumference – which enables them to channel more gas outside of the casing – and the stress put on the cement to casing bonds and cement to well wall interface.
The EPA might want to copy the illustrations from some of the service company brochures on the problem of “fugitive gas” or “methane migration” as this problem is commonly known in the industry. (To everyone else, it’s known simply as “Fox Faucet Flambe.”)
So I did a search of “fugitive gas” and “methane migration” in the EPA report. And guess what, they’re not there. Not mentioned once in 262 pages. Because if they were, the EPA would be acknowledging them as a problem. Which, apparently, they do not. Might point that out to them:
In addition to the progress report, EPA will be hosting a one-hour public webinar on Thursday, January 3rd, 2013 at 2:00pm EST, and again on Friday, January 4th, 2013 at 12:00pm EST. The webinar will provide project-specific updates that include research approach, status, and next steps. The webinar will also provide updates on five technical roundtables held in November 2012. To register for a public webinar, please visit: http://www.epa.gov/hfstudy/