52 TEXAS JOURNAL OF OIL , GAS , AND ENERGY LAW [ Vol . 16:1
structure for more oil . 37 Once the oil is found , the CO 2 “ mixes with the oil and mobilizes more of it — like turpentine cleaning paint — and then allows it to be pumped to the surface .” 38 In fact , Occidental Petroleum Corp . ( Oxy ) estimates that in some cases only 11 % of the oil in place upon discovery is ultimately produced from its shale reserves . 39 Generally , the oil is left behind because “ either it [ was not ] contacted by the injected fluid , or because of the capillary forces that exist between oil , water [,] and the porous rock in the contacted portions that trap and retain [ the oil ].” 40 As noted below , many operators believe that these remaining deposits can be recovered using the injection of pressurized CO 2 .
The application of CO 2 for EOR operations is not new . In fact , the first commercial CO 2 EOR projects date back to the early 1970s . 41 However , as noted below , the prevalence of these technologies have been constrained by a number of market factors , including the limited supplies of CO 2 . Many of the projects conducted to date have demonstrated dramatic increases in ultimate recovery . One case study , which analyzed CO 2 EOR operations conducted in Gaines County , Texas concluded that “ over 10,000 bopd can be shown to be coming from the [ flood ] interval , a zone that would have produced no oil under primary or water flood phases .” 42 A study on the subject found that CO 2 EOR “ has increased recovery from some oil reservoirs by an additional 4 to 15 percentage points over primary and secondary recovery efforts .” 43 The study noted that other pilot projects have reported “ incremental recovery of as much as 22 percent ” and further notes recent innovations could “ push total recovery in some reservoirs to more than 60 percent .” 44 According to Oxy ’ s website , “ CO 2
37 . David Biello , Enhanced Oil Recovery : How to Make Money from Carbon Capture and Storage
Today , SCI . AM . ( Apr . 9 , 2009 ), https :// www . scientificamerican . com / article / enhanced-oil-recovery /. 38 . Id . 39 . Ed Crooks , Chief Aims for Occidental Petroleum to be “ Carbon Neutral ,” FIN . TIMES ( Mar . 19 ,
2019 ), https :// www . ft . com / content / 74c859da-4a90-11e9-bbc9-6917dce3dc62 . 40 . MEYER , supra note 36 , at 1 . 41 . The first documented commercial project using CO 2 for EOR was the SACROC Unit located in Scurry County , Texas . Id . The project was initiated in 1972 and , as of 2016 , continued to produce about 29,300 barrels of oil per day . CO 2 : Overview , KINDERMORGAN , https :// www . kindermorgan . com / pages / business / co2 / eor / sacroc . aspx ( last visited Oct . 19 , 2020 ). Another example of a successful CO 2 EOR project was Shell ’ s Denver Unit in the Wasson Field , where it is estimated that injected CO 2 led to the incremental recovery of more than 120 million barrels of oil from 1983 through 2008 . Carbon Dioxide Enhanced Oil Recovery : Untapped Domestic Energy Supply and Long Term Carbon Storage Solution , NAT ’ L ENERGY TECH . LAB . ( Mar . 2010 ), https :// www . netl . doe . gov / sites / default / files / netlfile / CO2 _ EOR _ Primer . pdf . It should be noted that today Kinder Morgan ’ s SACROC and GLSA EOR projects use CO 2 produced from naturally-occurring underground deposits . Therefore , these projects would not be eligible for Section 45Q credits . However , the initial CO 2 flood was conducted with CO 2 that had been separated from produced natural gas and it wasn ’ t until the early 1980 ’ s that operators began piping CO 2 from natural sources . MELZER , supra note 35 , at 3 .
42 . ROBERT C . TRENTHAM ET AL ., CASE STUDIES OF THE ROZ CO2 FLOOD AND THE COMBINED ROZ / MPZ CO2 FLOOD AT THE GOLDSMITH LANDRETH UNIT , ECTOR COUNTY , TEXAS . USING “ NEXT
GENERATION ” CO2EORTECHNOLOGIES TO OPTIMIZE THE RESIDUAL OIL ZONE CO2 FLOOD ii ( 2015 ). 43 . MELZER , supra note 35 , at 14 . 44 . Id .