CHARLOTTE, N.C. - Moments before a group of concerned parents were set to meet to discuss their concerns about lead levels in CMS water Thursday, the school district announced they will test nearly 3 dozen more schools.

In August, the NBC Charlotte Defenders team discovered dozens of schools had lead levels more than 20 times over the acceptable maximum limit, but parents were never notified of the results.

The Defenders: Dozens of CMS schools report high lead levels

In a passionate meeting Thursday, parents and local leaders vowed to not let this slide.

“For a government entity to hide to study for nine months that is irresponsible behavior,” former Charlotte Mayor Jennifer Roberts said at the meeting.

Moments before the "Parent’s Right to Know" meeting began, CMS sent out an alert announcing they will continue their voluntary water testing at 35 additional schools starting Monday, promising to keep parents informed.

“Even if it was voluntary -- which I commend them for doing that -- once that information comes in, it should be distributed to the public,” said Luis Rodrigiez, a parent who attended the meeting.

And that’s not what happened the first time around.

CMS tested water for lead in 58 schools in early 2017. Many came back with levels well above the federal action level of 15 parts per billion: we’re talking school water sources clocking in at up to 430 parts per billion.

Experts say even levels of 5 ppb can cause a noticeable cognitive delay in children.

CMS said they either repaired, replaced or shut down the water sources that had elevated levels. But they never notified parents, telling NBC Charlotte there was no need since the problem was fixed.

“It’s enough to make you infuriated,” said Nakisa Glover, another parent at Thursday’s meeting.

Glover’s son attends University Park. She was horrified to learn a fountain in her child’s classroom might have been one of the affected sources.

“To find out a year later and on social media is completely unacceptable,” she said.

For now, her son is bringing water bottles to school.

“It’s hard to have that conversation with a 6-year-old,” she said.

Meanwhile, the group of parents and local leaders who met Thursday are putting their finishing touches on a plan to confront the CMS board this fall.

“CMS, keeping this information away from parents is very frustrating and something I want to get to the bottom of,” Rodriguez said.

Those looking to see the full list of schools that will have their water tested can click here.

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