Uranium Water Filter
An interesting fact popped out of a story that appeared in Wednesday’s Bee on uranium levels in the Valley’s groundwater.
Westport Elementary School in the Ceres Unified School District uses a filtration system to extract radioactive uranium from its well water. Without the filter, the uranium level would be well above the state and federal limits, according to the story.
In fact, the district initially installed the system roughly 12 years ago because of high nitrate levels, Ceres district assistant maintenance director Keith Gibson said. About five years ago, officials began finding unsuitable uranium levels, as well. So they added the uranium filter tanks, which last for about a decade and will be replaced by a private contractor sometime around 2020. The uranium recovered by the contractor could be suited for other uses, possibly as fuel at a nuclear reactor.
“They handle it,” Gibson said. “Whatever they do with it at that point is their business.”
Uranium is in the Valley water supply, Modesto Junior College science instructor Noah Hughes said, in part because it is common in the foothills and Sierra, where there is much granite. Granite is an igneous rock found all through the Sierra, including the Juniper Uranium Mine near Eagle Meadow in the Stanislaus National Forest. Most granite contains at least some uranium and therefore some level of radioactivity.
Because water runs downhill, whether it’s on the surface or deep in the ground, and because of more than a century of irrigating the Valley floor, some of the uranium made its way to the Valley aquifers. Too much of it, according to the report and the government.
Modesto and other cities monitor their wells, retiring those with excessive levels of uranium and other contaminants. Government agencies and water companies periodically provide testing results to their customers. Routine testing is done annually, with more expansive testing every five years. But residents who rely on wells are on their own to test their water quality.
“It is the responsibility of the well owner to ensure that their domestic well water is safe, since the State of California does not regulate domestic well-water quality,” according to the state’s Groundwater Ambient Monitoring and Assessment Program.
There are links on the page that list the labs certified to test groundwater for impurities as well as a listing of the most common inorganic or radioactive contaminants and their ceilings for allowable levels for human consumption. Testing costs from about $100 to $400 per well, depending upon the lab.
Man doesn’t need nature’s help tainting the water supply. We do a good enough job of our own, from chemicals that leach down through the soil to storm drain runoffs that pollute streams and rivers. Mining operations from the Gold Rush period used with mercury and cyanide to extract gold, and those contaminated the creeks and streams, as well. The list of contaminants on the state’s Web page stretches four pages in length.
In 2005, the federal Environmental Protection Agency for the third time ordered the Groveland Community Services District in Tuolumne County to cut down on the chemicals it was using to purify its water. The additives raised the levels of trihalomethanes and haloacetic acids, which can cause kidney, liver or nerve ailments and raise the risk of cancer. Groveland gets its water from Hetch Hetchy Reservoir, considered among the best and purest municipal water in the country. San Francisco’s water was safer out of the tap in the city than was Groveland’s just 39 miles from the reservoir, according to the testing, and the EPA gave the district until 2008 to comply.
The uranium levels in the eastern side of the San Valley rose by 17 percent from 1994 through 2000, the AP reported. Officials no doubt will monitor the impacts of the drought on contaminant levels, as well.
But at Westport Elementary, the drinking water is clean. In fact, for many of the students it’s likely the purest they drink all day if their own wells haven’t been tested and their water treated.