There are a couple of things that go on, as Dr. Gagnon has said, but we believe that one of the most important things is that a lot of the lead is in the form of solid particles that have adhered to the inside of the lead service line. When that's cut, disturbed, moved, or rolled up as part of the construction process, those lead particles get released. They sit in the pipe and, as water moves through the lead service line over the next period of months or years, those particles get moved into the plumbing and through the tap.
On November 23rd, 2017. See this statement in context.