Subtitle: Vilified Precision Directional Drilling To The Rescue
(Updated, see end of article. )
Approximately 12 weeks ago, a storage well for natural gas began to leak just on the outskirts of Los Angeles, California. The odor is intense in the nearby communities and many residents have been moved, relocated. Schools have been closed, and the affected students are being sent to nearby schools.
There have been dozens of articles written on this, and official information exists on various websites such as the South Coast AQMD (see link). The well is in some danger of blowing out and spewing a great quantity of odorized natural gas over the western portion of Los Angeles.
The AQMD site states:
"Southern California Gas Company (SoCalGas) operates a natural gas underground storage facility (Aliso Canyon Storage Facility) at 12801 Tampa Avenue in Northridge, CA 91326. Aliso Canyon Facility’s underground storage reservoir has the capacity to store over 80 billion cubic feet of natural gas. SoCalGas operates about 115 injection/withdrawal wells at this location. SoCalGas injects natural gas into the underground reservoir at this facility when the demand for natural gas is low and withdraws it when the demand for natural gas is high.
On October 23, 2015 SoCalGas discovered that a well used to inject and withdraw natural gas from the underground storage reservoir at their Aliso Canyon facility (known as Well SS-25) was leaking. Initially, it was expected that the gas leak would last no longer than several days or weeks, at the most. However, despite several attempts by SoCalGas to stop the leak, natural gas is continuing to leak from the underground reservoir through Well SS-25 and its surroundings." (note: Sempra Energy is the parent company of Southern California Gas Company.)
The facts, to the best of my knowledge, are that the well was drilled in the 1960s as an oil well. Once the oil ran out, and many years later, the well was one of dozens of similar wells that were converted to accept pressurized, odorized natural gas as a means of storing the gas during low-demand periods. When the demand for gas increases, the gas company withdraws the gas from the storage wells and sends the gas via pipelines to customers. Such gas storage and withdrawal facilities exist across the US. This one at Aliso Canyon is the largest in Southern California.
When this well began to leak, SoCalGas attempted several times to stop the leak by the usual and customary methods, primarily pumping a thick fluid known as "mud" into the well. However, this well did not respond and the leak increased. The quantity of gas and its odorizing compound created irritation and discomfort to the residents in the nearby community of Porter Ranch.
The situation attracted the attention of several state agencies and the Governor of California, who declared via proclamation "that a state of emergency exists in Los Angeles County due to this natural gas leak." see link
Since efforts to plug the well via mud injection failed, SoCalGas is drilling two relief wells to meet the leaking well at a prescribed depth. The relief wells take time to drill and reach the target. If successful, the relief wells will reduce the pressure in the leaking well and allow the leak to be plugged. see link to Department of Conservation's Fact Sheet on the well.
What is important to note is that the relief wells being drilled are using precision directional drilling (PDD), the same technique that is used all over the country and world-wide to economically drill and produce oil and natural gas from formations, including shale gas. PDD is used along with hydraulic fracturing to produce much more oil and gas than was possible years ago. It is commonly stated by the media that fracking is a new technology that causes all sorts of issues, including earthquakes and contaminated water. Both accusations are false.
The new technology, in fact, is not fracturing. The new technology is the gradual improvement in directional drilling, until today it can be called precision directional drilling. One superb example of PDD is the ExxonMobil oil field offshore of Russia's Sakhalin Island. That oil field is several miles offshore, and thousands of feet below sea level. The drilling rig is on the island near the mainland. Drilling more than 6 miles horizontally, and 8,500 feet down, the PDD reached the oil formation that is only 490 feet thick. As one executive described it, this is similar to standing at one end of a basketball gymnasium, then pushing a long pipe cleaner through clay and hitting a golf ball at the far end of the gymnasium. In short, PDD works.
At Aliso Canyon, the PDD must reach a depth of approximately something greater than 500 feet, but it must intersect with the existing well that is only a few inches across at that depth. If the leaking well is 4 inches diameter at that depth, or perhaps 6 inches, the precision of the PDD must be very, very good. The well is approximately the diameter of a softball, but the distance may be as much as one and one-half miles.
It is for this reason that the gas company has not offered any guarantees that the relief wells will work. However, there are good reasons to think that they will, eventually, reach the distressed well. The current schedule is for the wells to intersect in mid to late-February and for the leak to be stopped in early to mid-March.
It is ironic that the very same technology that many complain about, and condemn as causing so much trouble, is what will be used to rescue an old and leaky well that is approximately 50 years old. It is also ironic that PDD is what has allowed so much natural gas to be drilled and produced, and created a surplus of supply so the price of natural gas has declined to slightly less than one-third the peak price of a few years ago ($14 then, and $4 now, approximately). The low natural gas price leads to lower electricity prices, since much of California's electricity is produced by clean-burning natural gas. In addition, the US no longer imports LNG, instead, LNG is now produced for export to other countries. PDD is a modern miracle of applied technology.
As the situation at Aliso Canyon develops, there will likely be updates to this post.
Update 1 - 1/23/2016: SoCalGas states that they expect the well to be shut in by the end of February. Well, we shall see. Drilling such relief wells does not always go as planned. -- end update 1.
Update 2 - 2/13/2016: SoCalGas states they have temporarily shut in the well, with the gas flow stopped. The relief well was successful, hitting the leaking well with precision directional drilling. Next, the leaking well will be permanently capped by injection of a special concrete mixture that will harden and seal the well. However, the situation is not over, not by any means. Lawsuits will drag out for years. Regulators are discussing tighter rules. State agencies are evaluating the Aliso Canyon storage facility for suitability for long-term use, and the implications that has for energy security (electricity shortages and blackouts). --
see link to "Implications of Closing Aliso Canyon"
see link to "Natural Methane Seeps are Very Common"
see link to "California: As Gas Leaks, Pressure for Regulation Builds"----end update 2.
Roger E. Sowell, Esq.
Marina del Rey, California
copyright (c) 2016 by Roger Sowell - all rights reserved
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