Radon in Clark County
Clark County is predisposed to elevated levels of radon, a naturally-occurring radioactive gas, according to the Environmental Protection Agency. Clark is a Zone 1 radon county, with predicted average radon levels greater than 4 picocuries per liter of air. That’s the highest ranking a county can receive, according to an EPA radon map.
The gas comes from decaying uranium, which first became present in the region after massive floods swept the area at the end of the last ice age. During the Missoula Floods about 18,000 years ago, which originated from a glacial lake near Missoula, Mont., water flooded the entire Willamette Valley.
The floods brought granite rocks and sediment, which is high in uranium content. As that uranium decays, it gives off radon, a tasteless, colorless and odorless gas. Radon is toxic, and is the second-leading cause of lung cancer in the United States.
Some Clark County zip codes, especially those to the west along the Columbia River, are especially prone to elevated radon levels.
Home radon test kits are available at hardware stores for about $10 to $25.
Evergreen Public Schools has found elevated levels of radon at several campuses, including two that require additional action to bring radon to safe levels, the district announced in a news release Friday.
The district has contracted with Portland-based Cascade Radon to mitigate elevated levels of the radioactive gas — the second-leading cause of lung cancer — in the gymnasium at Sifton Elementary School and a classroom at Marrion Elementary School.
Sifton’s gym has levels of 11.1 picocuries per liter of air, while the classroom at Marrion has 4.2 picocuries per liter of air.
The Environmental Protection Agency recommends mitigation efforts at 4 picocuries per liter of air. Any reading above that is considered high for continual exposure.
This is not the first time those schools have had elevated radon levels. Public records obtained by The Columbian show the two campuses, among the oldest in the district, have had incidents of elevated radon dating back to 2001.
Public records show Orchards Elementary School and Crestline Elementary School also had elevated levels in this most recent round of testing, as well as other buildings at Sifton, but district spokeswoman Gail Spolar said the district has already done mitigation efforts in those rooms. That could mean opening air vents, removing posters covering vents or moving walls to improve air flow, she said.
“It really depends room to room,” she said.
A music room and music office had radon levels of 7.3 and 6.4 picocuries per liter of air, respectively, at Orchards, while a custodian closet at Crestline had levels of 4.2 picocuries per liter of air, according to public records.
A health room, instructional coach’s office, nurse’s office, parent center, physical education office and custodian office also had elevated levels of radon at Sifton.
The district began testing earlier this winter after completing lead testing at district campuses. That testing found lead at 12 of 33 district sites, according to Evergreen Public School’s website, including at Sifton, where two fixtures had elevated lead levels.
The school started by conducting its own testing, then brought in independent contractor Cascade Radon to conduct more sophisticated and accurate testing at those campuses that showed elevated levels, Spolar said.
The district is continuing to test all of its campuses for radon, Spolar said.
Neither Washington state nor the federal government requires radon testing.
Spolar said final reports were issued Thursday to the district. Teachers were informed that day of the elevated levels, and letters about radon went home with students Friday. The two rooms are closed off, and crews will begin mitigation efforts Monday, she said. Barring complications, work should be completed at the end of the week, Spolar said.
The district news release was issued at 3:30 p.m. Friday, just hours after the district provided results of a public records request to The Columbian for radon test results in recent years. The Columbian requested records for radon testing in late February, by which time the district had done its own series of unofficial radon testing.
Records dating back to 2001 show Sifton and Marrion have had other incidents of elevated levels of radon. Orchards and Crestline also had elevated radon levels, but Orchards has since been reconstructed, while Crestline burned to the ground in 2013 and a new building was constructed, meaning old test results reflect different buildings.
Test results from Clayton Group Services in June 2001 found elevated levels in three of five buildings at Sifton, including levels as high as 18.5 picocuries per liter of air in a core building. Marrion had elevated levels in one of four tested buildings with 10.4 picocuries per liter of air in a core building.
Ventilation modifications dropped those levels below 0.3 picocuries per liter of air by August 2001 at Sifton, but the core building at Marrion remained elevated at 5 picocuries per liter of air.
Additional testing conducted in December 2001 shows that building at Marrion was not analyzed again after Clayton discovered the test kit was left in a desk drawer of a maintenance building. The test results were not analyzed because they “would not be representative of the tested locations,” according to public records.
Sifton saw elevated radon levels again in 2009, when a library computer area, classroom and office had levels of 10, 11.5 and 12.2 picocuries per liter of air, respectively, over the course of a long-term test from October 2008 to June 2009. Mitigation efforts dropped those levels to 2.4, 2 and 1.8 picocuries per liter of air, respectively.
Sifton is 65 years old, while Marrion is 45 years old, Spolar said.
Evergreen Education Association President Rob Lutz said he believes the district has not done extensive enough testing in district buildings. The district has not responded appropriately to past findings of radon, he said.
“There’s a lot of concern,” said Lutz, whose union represents the district’s teachers. “I sat in a meeting at Sifton where risk management had laid out these results. There’s a lot of fear at this point.”
When asked if the union or any teachers were considering filing lawsuits against the school, Lutz said, “Everything’s being explored at this moment.”
“It’s really new whether there’s going to be any sort of action,” he said.