City: Chromium fix could cost taxpayers $110M

Evanston officials say that getting the metal chromium out of the city’s water supply likely would cost $110 million.

Levels of the metal in the city’s water are already at least 20 times lower than the 100 parts per billion the federal Environmental Protection Agency considers to be safe.

Evanston officials say that getting the metal chromium out of the city’s water supply likely would cost $110 million.

Levels of the metal in the city’s water are already at least 20 times lower than the 100 parts per billion the federal Environmental Protection Agency considers to be safe.

But an environmental group’s report, released Monday, suggests that levels here could be as much as three times higher than a 0.06 parts per billion standard being considered in California.

The federal standard applies to all forms of chromium, while the California rule would be limited to hexavalent chromium, which has been identified by the National Institutes of Health as a “probable carcinogen.”

Another form of the metal, trivalent chromium, is a mineral people need to metabolize glucose.

While the study, conducted by the Environmental Working Group, didn’t test Evanston’s water, it found hexavalent chromium levels of 0.18 parts per billion in samples from both Chicago and Milwaukee, and Evanston’s water division staff believes the level here would be similar.

The possible risk of hexavalent chromium was dramatized in the 2000 film “Erin Brockovich” which was based on an incident in which residents of Hinkley, Calif., accused the local utility company of leaking the chemical into groundwater for more than 30 years. But a recent California study found that cancer levels in Hinkley are not elevated.

The source of chromium in drinking water from Lake Michigan isn’t clear, but steel mills in northwest Indiana are known to dump substantial quantities of the mineral into the lake.

The city staff says Evanston would have to add a reverse osmosis membrane technology to its water treatment process to reduce chromium levels to the proposed California standard and that for a plant of Evanston’s size that would cost a minimum of $110 million to install and would require about $3 million a year in added maintenance cost. $110 million is roughly half the city’s total spending for a year.

The city currently has its water tested for chromium by Underwriters Laboratories, which can only test for levels down to 5 parts per billion. City officials say they’re now looking to find a laboratory that could test the city’s water for levels down to the proposed California standard.

A Washington Post report says basic home water filters like those made by Brita and PUR do not remove hexavalent chromium, but reverse-osmosis systems designed for home use that are available online and at hardware stores can take the chemical out of the water.

The California Environmental Protection Agency notes that bottled water is not required to meet any higher standards than city water supplies.

Update: Illinois’ two U.S. senators met with EPA officials in Washington Tuesday to discuss the chromium issue.