NASHVILLE, Tenn. – NewsChannel 5 Investigates first revealed that, as part of its lead-testing program, Metro Nashville Public Schools utilized a testing method that masks the real contamination problem in its drinking water.
MNPS responded by posting a claim on its website that “EPA VALIDATES METRO SCHOOLS’ LEAD TESTING PROTOCOL.” But our investigation discovered there’s a lot more to the story.
Related stories: MNPS Testing May Have Masked Water Contamination Flint Expert: MNPS Lead Tests Belong In Garbage Back in May, our investigation revealed that the district uses a protocol – called “pre-stagnation flushing” – that essentially washes away the evidence before workers collect water samples.
The top expert from Flint, Michigan, said MNPS’ results “need to be thrown right in the garbage” and the district needs to start over.
Ask Metro Schools, and they’ll point to the EPA’s published guidance for schools that says: “Ideally, the water should sit in the pipes unused for at least 8 hours but not more than 18 hours before a sample is taken.” MNPS has used that one sentence to justify sending crews out to schools to completely flush out the water lines the day before the samples are collected.
Go back to the sentence that MNPS likes to quote.
“However, water may be more than 18 hours old at some outlets that are infrequently used.
If this is typical of normal use patterns, then these outlets should still be sampled.” Later, in that same document where MNPS found the one sentence it likes, EPA says that testing should be “representative of the normal water consumption pattern.” In 2016, after the Flint water crisis, the EPA issued a "clarification" for public drinking water systems that pre-stagnation flushing does NOT represent a best practice.
Therefore, EPA recommends that sampling instructions not contain a pre-stagnation flushing step.” According to emails obtained through a public records request, MNPS spokesperson Michelle Michaud got an Atlanta EPA official to say that Grevatt’s memorandum “does not apply” to schools.
Special Section: NC5 Investigates: Lead in School Water