Quality report reveals McMinnville water OK
No violations regarding testing of McMinnville’s water supply were issued from the Environmental Protection Agency, according to a recent report mailed to city water consumers.
To the layperson, the annual report may raise eyebrows when one looks at the category of “maximum contaminant levels,” which at first glance mentions contaminants in the present tense as if they actually exist.
But a representative from the EPA’s safe water drinking hotline said those notes reflect what the contaminant levels are in terms of the level of contamination for which there is no known or expected health risks, not what is actually there.
In McMinnville’s water report, total coliform (bacteria), a contaminant that is naturally present in the environment, was detected, which is reflected in the report.
Water and Wastewater Director Carl Davis said the detection of total coliform in McMinnville’s water may mean an inaccurate reading. The test is repeated as a matter of procedure and if it is negative, it is considered negative. Another negative result is if the contaminant does not go over maximum contaminant levels.
Total coliform is not harmful in itself, EPA notes, but a true positive indication reflecting the presence of total coliform in 5 percent of monthly samples requires further testing for harmful bacteria such as E. Coli or fecal coliform. That was not necessary in McMinnville because there were no two positive tests for total coliform, Davis said.
Daily tests are performed at the consumer’s tap for coliform bacteria, while others are performed weekly and quarterly. Officials also tested for atrazine and arsenic, but those levels were well under the maximum contaminant levels as well, he said.
Two EPA mandates that took effect Jan. 1, 2002 for all water systems require reduced levels of total trihalomethanes and haloacetic acid, which may cause cancer. Davis said the amounts in city’s water are currently well under those levels already.
He also noted the chemical that was changed to treat turbidity, or cloudiness, of water after January’s floods, is performing well.
“It was a very good report. Everything was under limits,” Davis said.
More information on public water systems can be found at the website www.epa.gov/safewater.