No, just the one I mentioned. With the exception of plastics, we've been using pretty much the same materials to make water pipes for over five thousand years, so there's really not much experienced engineers and chemists won't already know about what NOT to do to pipes to compromise them. For example, if you've ever changed out really old pipes in a home, you might notice a thin white coating on the incoming pipes. That's calcification. That stuff is what makes tap water "hard" and why people use fabric softeners in their laundry. It's why the Romans could make pipes out of lead, but leave archaeologists stumped as to why so few of them suffered any signs of lead poisoning. The other thing is that lead poisoning is really easy to spot in human beings in their soft tissues. If what's going on in Newark is similar to what went on in Flint, Michigan, and other cities, it means the lead poisoning was deliberate not accidental. The pipes that are leaching lead into the water have been in service for a century or longer, but it's only been recently that people are reporting lead poisoning. For their not to be constant lead poisonings in the intervening decades means that the bulk of the water infrastructure had long since calcified. The only way to undo that and not pull out hundred of miles of water works is to run chemical corrosives through the entire network. Conveniently enough, you can find such chemicals in any local rivers near the affected cities in the industrial run off. If those cities have to pay money to access reservoir networks miles away from the city, then you've got the monetary motivation local politicians would have to slowly poison people with leaded toxic water. Greed doesn't compel people to poison thousands, potentially millions, of people. Only evil does that and that can only occur in people devoid of any morality who believe they will never be punished for their crimes.