The rippers on a motor grader, excavating a building pad. I was ripping outside the pad line so the scraper could pick up the material and build himself a ramp going into the cut, we had 6 1/2 feet of cut total. My boss failed to inform the scraper operator and I that there was a water main 6' from our pad line and 2' down. The boss is an old man that didn't like me to begin with, so he blamed it all on me saying I shouldn't have been outside the pad line. We argued about him not saying shit about it. I ended up having to take a pee test for the main contractor and was kicked off the job.