After Black Mesa plummeted into the ground 200 years after the incident, it was brought back to life by a group of Blue-Headed men all named "Jamie". Jamie and all his friends now work at the lab, and ironically enough the same exact thing that happened 200 years ago happens again. Even with Gordon Freeman brought back from the dead.
i was bored so i messed around with the sound files just a little bit, not much is changed but it has new music in it.