CHICAGO (AP) — A group of Chicago aldermen want hearings on the amount of lead being found in water at some city schools.

Alderman Scott Waguespack says the aldermen are looking for a comprehensive plan to address the issue of lead in water in the city. He and other members of the Chicago City Council’s Progressive Reform Caucus are demanding the hearings.

So far 19 Chicago Public Schools buildings have had tests uncover lead levels that exceed a federal standard of 15 parts per billion. Chicago Public Schools officials say the district has tested water at 224 of 324 school buildings that were constructed prior to 1986. So far, the district said it has received test results for 74 schools.

District officials say water at all public schools will be tested.