Nice Discussion of "Re-Entering" Old Wells in North Dakota

Link here.

Again, for newbies, the entry by Teegue at that link is key.

This is an issue I do not understand -- re-entering "old" wells, but I will probably learn as I go along.

Some data points:

1. The general consensus is that drillers do not find it cost effective to go into "old wells."

2. It was my understanding that in North Dakota, an abandoned well / plugged well was the end of the story. An operator could not drill into that plugged well again. The whole process had to begin anew and the new well would be in the same location but not through the plugged well. I may be incorrect on this.

3. Regardless of whether one is allowed to drill through a cement-plugged abandoned well, most old wells are situated in the wrong location within the section for most new horizontal wells. The drillers want to site the well as close to the section line as possible to drain as much of the section as possible; old wells were farther from the section line.

4. Having said all that, unless I misunderstand the definition of "re-entry" or I am mis-reading some file reports, there are examples of wells that have been re-entered. One such example has turned out to be a very good well. Note: this well was DRY in the Red River formation, totally abandoned the Birdbear formation, and then hit a very nice payzone in the Bakken.

Again, this issue is confusing to me, but more to come, I'm sure.