Radon tests point to school ventilation systems

Results of radon testing at school sites in the Lake Tahoe Unified School District were presented to the school board Tuesday.

More than 15 percent of the tests were at or over the Environmental Protection Agency's recommended action level of 4 picocuries per liter of air (pCi/L). A picocurie is a measure of radiation. Radon is a naturally occurring radioactive gas.

In all, 460 tests were conducted within all district-owned buildings, including the schools. Of those, 72 showed results over the EPA action level. Of the results that were high, most of the levels were between 4 pCi/L and 5 pCi/L, said Steve Morales, director of facilities for the district.

Morales said the tests were conducted Nov. 28-30 at the high school and middle school. Tests were done at the remaining school district sites Dec. 3-5.

Of all the sites, the former Al Tahoe School site had the most tests with results over the action level, which Morales attributed at least in part to the heating, ventilating and air conditioning (HVAC) system not running continuously.

George Faggella, staff environmental scientist for California Department of Health, supervised the testing, Morales said.

Morales said they found a strong correlation between areas that showed low radon levels and modernized HVAC systems; areas that had higher levels of radon had older HVAC systems.

Morales said the systems have been looked at and repaired, and he thinks the results can only get better. "I feel this is the worst-case scenario that we are seeing right now," he said.

Free radon test kits Available at the El Dorado County Environmental Management Department, 3368 Lake Tahoe Blvd., Room 303, while supplies last. Call (530) 573-3450.

Retesting of problem areas began Wednesday.

Depending on the test results, other forms of mitigation could be discussed next March.

"It's too early to jump into those right now," Morales said.

Parents who are concerned about radon levels in schools also should be concerned about levels in their homes, said Virginia Huber, division manager for the El Dorado County Environmental Management Department.

In South Lake Tahoe, 50 percent of homes have radon levels that exceed the EPA's recommended limit. People generally spend more time in their homes than anywhere else.