On Wednesday, February 13th, Rio Grande County Commissioners approved First Liberty Energy’s Conditional Use Permit to drill an oil exploration well northwest of Del Norte on Old Woman Creek. According to county officials, First Liberty has committed to double casing all the way from the surface to 200 feet below the bottom of the Conejos formation – a depth of about 4,800 feet.
These are are all good things - the possibility of commercial oil production in the valley, FLE’s offer to case through the Conejos formation without that being a pre-condition for approval, and the county’s approval of the CUP.
But they’re not as good as they could have been.
For one thing, a First Liberty plan to test the thick Lewis/Mancos shales for gas, as well as looking for conventional oil would have much more economic potential for valley folks, and perhaps for FLE as well.
Also, relatively little is known about the lithology, permeability, and hydrology of the lower 3,000 feet or so of the Conejos formation. Electric logs and other data gathered during drilling will likely provide critical information on which FLE and county officials should base a suitable casing plan. FLE’s offer to case entirely through the Conejos formation, although quite generous, may prove to be either too much or too little, depending on actual downhole conditions encountered. Further, it could set an unwarranted precedent for future O&G exploration.
And finally, the FLE casing plan completely overlooks the Blanco Basin and Animas formations, a 1600-foot section of Tertiary sediments just below the Conejos formation, and possibly containing much better aquifers than the Conejos formation.
Both proponents and opponents of oil and gas drilling in the western San Luis Valley should all hope that First Liberty Energy’s actual final drilling/casing plan will be based more on science and economics and less on guesswork.