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Wednesday, June 25, 2008

Illinois oil

Back on May 17, 2008, the Illinois Petroleum Council told us that Illinois is "the fourth-largest oil refining and transporting state." I've been thinking about that since then, and while I haven't been able to figure out exactly what that means, I have found some other interesting and noteworthy things.

First of all, those rusty iron teeter-totter looking things we see dotting the countryside are "pump jacks" or "horse heads." (Link and photo.) Good to finally know what those are called.

From a 2005 AP article:

[...] 33 states produce oil and natural gas, with Illinois ranking 12th among drilling states or regions, just behind the Gulf of Mexico. Oil drilling is going on in about 40 of the state's 102 counties, mostly by independent operators. [...] Most wells in Illinois put out about 1.5 bpd, according to the group. Since 1989, the amount of crude retrieved state-wide has dropped by half to about 11 mm barrels a year -- less than 1 % of the total produced nationwide -- because the large price declines in the last two decades pushed people out of the business....

So, if I'm reading that right, one well in Illinois produces about 1.5 barrels of oil per day, for a total of 11 million barrels per year for all Illinois wells. At that rate, that's a lot of wells. Remember, these figures came from a 2005 article.

By the way, there are 42 gallons of oil in a barrel. And a barrel of oil produces about 19.5 gallons of gasoline. (Link.) I think I read somewhere that Illinois oil actually produces less than the average for some reason. But, I can't back that up at this moment. If I find it, I'll come back to it.

Most of the oil in Illinois comes from the region known as the Illinois basin:

The llinois basin is a northwest-southeast asymmetrical structural depression that is filled with more than 4000 meters of Paleozoic sedimentary rocks. The basin is bounded to the north by the Mississippi River and the Kankakee Arch, to the east by the Cincinnati Arch, and to the south by the Ozark uplift and Pascola Arch (McDowell, 2001). (Wiki.)

When last we discussed the Illinois basin here, it was in reference to the April 18, 2008, earthquake. Oil. Earthquake. Geologic. Ahh. I'm getting it.

From the Illinois State Geologic Survey: A GIS Approach for Play Portfolios to Improve Oil Production in the Illinois Basin, we learn:

Oil and gas have been commercially produced in Illinois for over 100 years. Existing commercial production is from more than 52 named pay horizons in Paleozoic rocks ranging in age from the middle Ordovician to Pennsylvanian. Over 3.2 billion barrels of oil have been produced. Recent calculations indicate that remaining mobile resources in the Illinois Basin may be as much as 4.1 billion barrels. Thus, large quantities of oil, potentially recoverable using current technology, remain in Illinois oil fields despite a century of development. (Emphasis in bold added; see also, Underdeveloped Areas Evaluation Techniques, and Illinois Oil Interactive Map.)

Some Illinois statistics:

  • There are approximately 32,100 oil and gas production wells, 10,500 Class II injection wells and 1,750 gas storage wells in Illinois. These wells are controlled by 1,500 operators.
  • The Division of Oil & Gas conducts approximately 22,000 inspections per year and initiates approximately 3,500 enforcement actions each year.
  • Approximately 800 drilling permits for oil, gas and injection wells are issued each year.
  • The majority of wells in Illinois are stripper wells with a daily production of 1.5 barrels per day.

In Illinois we have several industry lobbyists, including the aforementioned Illinois Petroleum Council (can't find a web site), and the Illinois Oil and Gas Association. But, it's not all about the producers. It's also about caring for the land. So, we have the Illinois Petroleum Resources Board, which is funded by "voluntary contributions of oil and natural gas producers and royalty owners in Illinois," and:

[...] provides funding and expertise in the reclamation and restoration of abandoned oilfield sites in the State of Illinois. These restoration projects fulfill another goal of IPRB which is to restore land previously used for oil and gas production back to commercial, agricultural use for current land owners.

I doubt if any environmental watchdog group is looking into this. But, hey, it's the producers' and farmers' land (mostly), so we trust them to do the right thing by themselves. I guess. In Illinois, the Department of Natural Resources Division of Oil & Gas "is the regulatory authority in Illinois for permitting, drilling, operating, and plugging oil and gas production wells." (See also, Landowner Grant Program, and the Plugging and Restoration Fund Program.)

They don't just take the oil out of the ground and walk away:

When oil is brought up from beneath the surface of the earth, saltwater is mixed in with the oil. The saltwater must be removed and properly disposed. This is done by placing the saltwater into another type of well called a "Class II injection well" that puts the saltwater back beneath the surface of the earth into an appropriate geologic formation.

In order to protect the environment and our drinking water, it is very important that Class II injection wells be properly constructed and operated. The Division of Oil & Gas requires that anyone who wants to construct and operate a Class II injection well must first meet rigorous technical requirements and obtain a permit for that activity from the Division. This program is called the Underground Injection Control Program ("UIC Program"). The Division of Oil & Gas is authorized by the United States Environmental Protection Agency to implement the UIC Program for Class II injection wells in Illinois. (Link.)

This is a little baffling. Or, maybe I'm just not trying hard enough to understand this whole saltwater thing. How does it happen that the oil comes up and gets mixed with saltwater? Is this intentional? Where does this saltwater come from? Do they truck it in all the way from the ocean? That seems unlikely. So, they must mix it up on the spot. But, doesn't it seem like extra work to intentionally mix the saltwater in with the oil only to have to remove it later? In any event, it sounds like the oil that is removed from the ground gets replaced with saltwater. Interesting. I wonder how they thought that up.

And, now we know a little more about Illinois oil. Also, assuming the U.S. imports at least 3 billion barrels of oil per year, I think we can safely conclude Illinois, with its measly remaining 4.1 billion barrels, won't be solving the price of oil crisis. While this is by no means exhaustive research, I'm a little exhausted after putting it together.

Posted by Marie at June 25, 2008 1:01 PM


When oil is pumped from a well often salt water naturally comes with it. This salt water is water that occurs organically within the rock with the oil. The oil and water is separated at the surface in a tank called a “receiver”. The receiver is the tall, skinner tanks. The oil is then stored in the shorter tanks until sold. The salt water (or brine) has to be disposed of in an environmentally sensitive manner and is normally reinjected into the same formation that it was pumped from. The brine can also be hauled to another oil field and injected there, again in an oil producing formation. Often this brine is used to maintain the pressure in an oil field and to drive more oil to the producing wells

(from Schlumberger’s oil filed glossary)
formation water
Water that occurs naturally within the pores of rock. Water from fluids introduced to a formation through drilling or other interference, such as mud and seawater, does not constitute formation water. Formation water, or interstitial water, might not have been the water present when the rock originally formed. In contrast, connate water is the water trapped in the pores of a rock during its formation, and may be called fossil water.


Posted by: rod at July 7, 2008 2:43 PM

Excellent and good to know. Thank you for sharing your knowledge.

Posted by: Marie at July 7, 2008 8:57 PM