I am researching the subject of how fracking/injection wells and the resulting seismic activity will affect the old room and pillar mines that are underneath many of our homes and businesses. Not coming up with much information...would love to hear your thoughts on this!
I have seen the old mine maps that ODNR posted and compared those to the new horizontal wells and I can only find one horizontal drilled under a mine in Belmont county. at this point it doesn't look like they are
Very interesting, thanks for the reply...I wonder if fracking will affect adjoining property, as in triggering mine subsidence?
The coal under my land in Belmont is 600-700 ft down. The horizontal wells in Belmont are over a mile below those coal seams.
Should not be any problems between the two. Most mines are only a few hundred feet deep compared to 7-9000 Ft for the wells.
RE: "I will say that a lot of the old mines have posts that are 50 to 100 years old. It would not take a lot of vibration to cause a localized collapse."
I would anticipate that the fracturing of the rocks at 7000 feet beneath the coal mine workings would have no effect on subsidence or collapse.
Any risks of subsidence or collapse would likely be associated by vibrations and loading caused by surface activities .... heavy truck traffic, pipeline working, active drilling equipment, compressors, pumping, and other surface disturbances.
What happens at 7000' stays at 7000' .... what happen at and near the surface is another story.
You might consider contacting the Geology Department at WV (specifically Thomas Wilson, Professor of Geophysics). For a relatively modest amount, the State might fund a graduate Student to seismically monitor drilling and fracing of a well drilled near or over known old mine workings; the State would (cheaply) obtain hard data, the student would get a Master's Paper. Science and data trumps any conjecture.
But why is the drilling companys not putting laterals under these areas of abandon mines?
Is it due to the State not permitting them?
RE: "But why is the drilling companys not putting laterals under these areas of abandon mines?"
I have seen proposed well pads with laterals which do extend under old abandoned mines. I suspect that there have been a number of laterals drilled which extend under old abandoned mines.
I know that in 'my neck of the woods' the older the mine, the less we know about the location of the shafts and the extent of the workings.
I know of people who have drilled water wells in locations which were supposedly not mined, only to penetrate an old mine shaft.
I have been told that in the 19th and early 20th centuries, unscrupulous coal operators frequently took coal from adjoining properties; faking the mine surveys.
Also, the surveying of mines via transit and stadia rod in the 19th and early 20th centuries was more an inaccurate art than science.
A drilling contractor would not want to locate the first few hundred feet of the vertical portion of the well over a known mine shaft .... they would have trouble pumping enough cement into the void to cement in the casing.
But, I see no problem with or reticence to drilling a lateral 7000' below an abandoned mine.
Does anyone reading this know of an example where a lateral has been drilled under old mine workings?
Does anyone reading this know of an example where a permit was denied because the lateral was proposed to be drilled under old mine workings?
I have land in a coal bearing part of Belmont county. In the case of coal owned by Murray in Belmont county, before we signed a lease in late 2012, we were told that the vertical part of the well can't go through an open area in an old room and pillar mine for fear that natural gas would leak into the mine and create an unsafe mining environment. We were also told that the vertical portion of the well couldn't go through an area that was previously longwall mined for fear that natural gas would leak into the mine and create an unsafe mining environment. We were also told that the vertical portion of the well could not go through a coal seam that was scheduled to be longwall mined in the future because it "would cost a million dollars to go around it". Coal was king in SE OH for a LONG time and they have a huge say in where wells are located that pass through their coal holdings. In my experience, most of those coal rights were purchased over 100 years ago from the landowners.
My personal opinion is that the O&G producers had to figure out how to compensate the coal producers so that both could get along. It seems to be happening as we've seen a number of permits in Belmont.
Thanks Finnbear for your information.
I have heard of an occasion, while drilling in an karst area (an area with near surface and shallow limestone), where the bit suddenly dropped 30'; as all the drilling mud disappears .... as the bit penetrated an underground cavern. That gives new meaning to "lost circulation". Luckily this sort of happenstance is rare and occurs shallow .... just move the rig over a ways and hope for better luck.