In mid July, I was driving down rte 9 going west. I noticed a tanker type truck across rte 9 on the east bound side. It was pulled over against the woods (town forest) right before you get to McDonald's. There was a man outside standing next to the truck what looked like pulling in a pipe line from the woods. I was going too fast to take a picture or get the name off the truck. All I remember seeing was it was a black truck. Maybe a sewer truck dumping his load? Didn't have time to make a u turn and catch up to him. I called the Natick police that afternoon but they said next time you see it , call us. I'm hardly ever over in that area. I grew up in Natick and I know that the town's drinking wells are in the woods there. Hopefully you can test that area?