Health officials in northeast Washington say if you get your water from a private well, it’s a good idea to have it tested for uranium.
A new survey by the USGS confirms the uranium threat is widespread. Uranium is a naturally occurring mineral in the region and nationwide.
Sue Kahle is a USGS researcher who says her agency did a survey last year of 13 private wells. Half had levels of uranium above 30 micrograms per liter, the Environmental Protection Agency’s standard for drinking water.
She says they also looked at previous data collected from various sources from the past 40 years.
“For the historical data set, there were more than 1700 wells sampled. And of that sample there were only 5% that were above the MCL, so in terms of where they are, they can be all over the map,” Kahle said.
MCL refers to the federal standard, or maximum contaminant levels. She says the median for all the wells was about 2 micrograms per litre, well below the safety threshold. But other concentrations were as high as 1180 micrograms per liter.
“Based on that historical data set, as limited as it is, the highest concentration in a drinking water well was the Huckleberry Mountains in north central Stevens County. Then, based on the recent samples we collected last July, and again that was very limited, 13 samples over four counties, the highest concentrations were found in wells on the west side of Mt. Spokane,” she said.
Matt Schanz of the Northeast Tri County Health District, which serves Ferry, Pend Oreille and Stevens counties, where 54% of the population gets water from private wells, explains the health threat posed by the uranium contamination.
“The reason why the threshold was set at 30 micrograms per liter is based upon the increased risk of kidney damage, just because this naturally occurring uranium is a heavy metal, and can have damage to the kidneys over long term exposure,” he said.
Schanz says the cancer risk is also increased, but because most water based uranium concentrations are low, the main risk is kidney damage.
He says there is an easy fix to prevent the uranium from being ingested.
Schanz says while several counties require testing of new wells for presence of the mineral, those with older wells can get the testing done for as little as 30 dollars, by contacting the Health District for more information. And he says simple filters are readily available at home improvement stores.
“The most feasible alternative for removal of uranium is point of use systems using reverse osmosis, and those are commonly available units that fit under a counter, and it’s where families can get the majority of their drinking water supply,” he said.
Schanz says the health threat is from drinking water only, and exposure by other means, like bathing, does not pose a risk.
He says while several counties require testing of new wells for presence of the mineral, those with older wells can get the testing done for as little as $30, by contacting the health district for more information. He says simple filters are readily available at home improvement stores.
