What is The Real Risk of Temporarily Abandoned Wells?

The headline reads:

AP Exclusive: Share of aging temporarily sealed wells grows

Sounds terrible doesn’t it?   The story goes on to look at the number of temporarily abandoned wells in the Gulf of Mexico:

—Twenty-five percent more wells have now stayed temporarily sealed for more than a year (up from 2,855 to 3,576) and  The number of wells equipped with temporary barriers for more than five years has risen from 1,631 to 1,895 — a 16 percent increase.

The article says 20 of the wells have been listed as “temporarily abandoned” since the 1960s.  It raises the danger that wells could leak and refers to the 2010 Macondo blowout, implying there is some connection between the risk from temporarily abandoned wells and the actual spill resulting form Macondo.

But is there?  Do temporarily  abandoned wells present a true threat?  Before we get into it, let’s be clear on a few points:

  1. No spills are acceptable.
  2. Industry has an obligation to remove idle iron.
  3. Small leaks seeping from temporarily capped wells can go unnoticed for quite some time and the volume can add up.
  4. A little oil on the water can create a very long slick.

However, as far as actual risk goes, is this really the problem that is implied by the report?  First, let’s remember why they were shut in in the first place – they were played out.  If there is not enough oil or gas to support commercial production, the potential volume that could spill is also limited.

Second, the spill data from the Gulf tell us what is actually happening in the field.  If the risk of a catastrophic spill was high, we should see some evidence in the statistics for spills in shallow water where almost all of the temporarily abandoned wells are located.  We don’t.   In 2012, there were eight spills of any type (crude, lubricant, coolants, etc.) that were greater than 50 barrels in the entire Gulf.  Only one of them was on the shelf and it was also the only crude oil spill.  Significantly it was a working production platform undergoing maintenance, not an abandoned well.   In 2012, there were 17 other smaller oil spills totaling 133 barrels, but the BSEE statistics don’t indicate what subset of that were plugged wells.  Even with this limited information, we can see that the data does not indicate a pervasive problem or even an increase in spills from temporarily abandoned wells.

None of this is to say we don’t need to remove wells that have outlived their usefulness.  However, a focus on a relatively small threat of a major spill ignores the real risk from decommissioning wells – people can get hurt doing it.  Idle iron may not be maintained adequately, creating its own risks.  Structure removal brings with it unique hazards. The incident history also indicates that a number of small spills happen during capping and removal; more activity, higher risk.

But an investigative report that wags its finger at BSEE for allowing so many temporarily abandoned wells offshore misses the point. BSEE’s focus really needs to be on ensuring that timely removal is done effectively and safely, not in rushing to remove them because of a spill risk that has been relatively modest.

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