OTHELLO – A source of fluoride in well 6 was located and the Othello City Council is working to determine a plan to block a large identified source.
The well is approximately 1,200 feet deep and produces more than 3,000 gallons of water per minute. It’s the largest well in the city.
The council has spent several months trying to identify the fluoride sources in the well. The fluoride levels are currently too high for human consumption so the council researched solutions to decrease the contaminant level.
The average amount of fluoride pumped from the well is 4.6 to 4.8 milliliters per liter, hydro-geologist Kevin Lindsey said. To comply with state Department of Health requirements the fluoride level can’t be higher than four milliliters per liter, he said.
The highest-producing fluoride zone is between 915 feet and 930 feet below the well’s surface, he said. The zone is estimated to produce between eight and possibly up to 15 milliliters per liter.
Lindsey said it appears the average amount of fluoride produced from the well might go below four milliliters per liter if the zone is sealed. He said he wants to research his suggestion further before making a final recommendation to ensure the average fluoride level is below four milliliters per liter.
Lindsey said the high fluoride level is located in a high-producing water flow zone and there is potential the city could lose up to one-third of the well’s capacity attempting to seal the fluoride source.
“We’ve got some challenges there,” he said. “There’s a bad fluoride source there.”
Councilmember Ken Johnson asked if there is enough evidence to prove to the state Department of Ecology that the Grand Ronde and Wanapum aquifers are not commingling in the well.
Lindsey said he feels confident he can put together a report arguing the two aquifers are not commingling. He said it’s difficult to get ecology to approve the well if there are two aquifers commingling. He said the report should be complete by the end of this month.
Mayor Shannon McKay and Councilmember Eleanor Brodahl were absent from the meeting.