In a brief hearing to confirm a consent administrative order, the Arkansas Oil and Gas Commission (AOGC) reached an agreement with the operators of two disposal wells in the Enola Swarm seismic zone to immediately cease disposal operations. The wells were located in S17-T8N-R12W and S6-T7N-R12W in Faulkner County, Arkansas.
The order will be in effect until the last day of the March, 2011, AOGC regular hearing. At the regularly scheduled March hearing, the AOGC will hear the entire docket including evidence and public comment. There will be pre-hearing conferences between the AOGC staff and the operating companies prior to the hearing. In giving the consent order, the companies operating the disposal wells admitted no culpability for the recent seismic activity in the vicinity of their wells.
The matter of disposal wells causing seismic activity is under study, and the AOGC placed a moratorium on all new disposal wells in the Enola Swarm area in December 2010. Read more about the docket here. The documents from the December hearing, including an article about the theory of induced seismicity by disposal wells are here: Part1 and Part2.
AOGC staff reiterated that they had no evidence that hydraulic fracturing, a process related to extracting gas from the Fayetteville Shale, had any connection with the seismic activity. Hydraulic fracturing takes place at a much shallower depth than disposal, and the fluids used in fracturing are recovered and not left in the ground. There is speculation that seismic activity related to disposal wells occurs because the disposal fluids remain in the ground at a depth where seismic activity occurs, possibly lubricating faults to induce seismic activity.
Many media outlets, industry representatives, and interested citizens were present at the hearing. Because the order was admitted by consent, no evidence was taken at the hearing.