Then came testing at elementary schools, followed by middle and high schools. The testing finished before the school year began, with samples tested from 797 water sources in all 72 active school buildings.

“What we looked at were the drinking fountains,” said Jeff Faust, managing principal of Environmental Consultants LLC. “We went to the cafeterias and kitchens and sampled the sinks, the hand washing and dish washing stations. We also went to the teachers’ lounge where we sampled the sinks, the water used to make coffee.”

Samples were “first draw” samples, meaning the water had been in the pipes for at least six hours prior to sampling to get the highest readings possible.

“They wanted to know: How bad can this problem be?” Faust said.

The Environmental Protection Agency requires action to be taken if lead levels in drinking water reach 15 parts per billion. St. Louis school officials made 10 parts per billion their action level — turning off any water source that met or exceeded that amount.

At least one sink or drinking fountain was shut off in 32 buildings. Bottled water is being distributed at 13 schools where a significant number of drinking fountains are turned off or inoperable.