08.03.16. The state of Oklahoma is ramping up its earthquake preparedness in response to a growing risk of tremors.
Oklahoma Corporation Commission’s (OCC) Oil and Gas Conservation Division (OGCD) has announced actions to reduce further the amount of oil & gas wastewater injected by Arbuckle (south of Oklahoma City) disposal wells in earthquake areas and increase the size of the so-called ‘yellow light’ area.
The Panhandle state experienced 907 magnitude 3+ earthquakes in 2015, up from 585 such tremors in 2014 and 109 in 2013.
The state government says the recent rise cannot be entirely attributed to natural causes. Seismologists have documented the relationship between oil & gas wastewater disposal and triggered seismic activity. The Oklahoma Geological Survey has determined that the majority of recent earthquakes in central and north-central Oklahoma are very likely triggered by the injection of wastewater in disposal wells.
In October last year, a 4.5 magnitude quake was recorded a just a few miles from the town of Cushing, which hosts the largest commercial oil storage hub in the USA.
OGCD director Tim Baker said the central Oklahoma action will cover more than 5,000 square miles and more than 400 Arbuckle disposal wells.
Baker said the goal is to reduce the total volume disposed in the area to 40 percent below the 2014 total. “This means a reduction of more than 300,000 bpd from the 2015 average injection volumes,” he explained.
In a separate action, the OGCD is also expanding the size of the ‘Area of Interest’ (AOI), bringing more restrictions to disposal well operations in areas that have not yet seen major earthquake activity.
“The central Oklahoma volume reduction plan covers an area where we have taken numerous, localized actions over the past 12 months, such as in the Cushing, Crescent, and Edmond areas. But the research and data has grown to provide the basis needed both to expand into a regional approach for volume reduction and increase the size of the AOI,” said Baker.
8th March 2016
