Now that Dave has shown it doesn't matter whether or not you put the anchor in the model, I'm going to suggest that you don't add the anchor (contrary to what Dave suggests). The reason being that too many people think there is a real anchor there. Here is a perfect example....

A few years ago someone called up complaining that the pipe in the field didn't behave the way CAESAR II said it would. I asked for an explanation. What they had done was run CAESAR II to obtain the distance to the virtual anchor. They then went a few hundred feet past that location, and dug up the pipe to insert a valve. They were most surprised (and upset) when the pipe jumped out of the ground - after all, they were past the virtual anchor, there shouldn't have been any movement ??

Most people don't understand that you can never reach the virtual anchor. If you're standing at "point A", and you compute the virtual anchor to be at a distance of 1500 feet away, and you walk 500 ft in that direction, the virtual anchor also moves 500 ft.

Perhaps we should remove all references to the term "virtual anchor" and replace it with the phrase "point where it is ok to stop modeling", assuming nothing else changes.