Gas Main Replacement

I've passed this hole in the road on my way to the bus stop most days recently. I'm slightly fascinated by the new holes in the top of the pipe (with rusty plugs) that they sometimes attach guages to, the blue end caps, and the piece of wood spanning the gap in the pipe. I'm assuming this is part of the old gas main, since the work going on is to put in a new gas main?

I've already blipped the urban snake that they are installing...