Loudon County Air Quality Task Force members remain opposed to the Tennessee Department of Environment and Conservation removal of the air toxics monitor at Fort Loudoun Middle School. 

Mike Crosby, task force president, said he had contacted Qunicy Styke III,  deputy director of TDEC's Air Division, and that Styke had informed him the monitor removal was slated for June 30. 

Officials have since decided the monitor will stay for an undetermined period of time.

Task force members said they were especially concerned about the potential loss of the monitor because they still have many unanswered questions about the alarmingly high acrolein levels found by TDEC earlier this year when original air toxics monitor data was reviewed.

"I'd like to get more definitive answers," Crosby said. "We still have unresolved issues. I would like to get more help from TDEC and EPA about where the emissions are coming from. Also, we have no indication of how serious it is."

The late June meeting was the task force members' first opportunity to discuss the EPA document purported to provide answers to their questions.

The task force had submitted a dozen questions about acrolein to EPA in March and received the agency's answers in late April. 

The document was not discussed in April because task force members had not had time to review the response. 

The May meeting was cancelled because of conflicts.

Review and discussion of the document was placed on the agenda for June 24. However, after reading the EPA answers, task force members said they still were unclear about the effects of high acrolein levels, whether the health risks are acceptable. 

"The answer to question two is most troubling," Crosby said. "You've got to wonder whether it is a hazard."

Question two stated : Non cancer risk: Hazard of 1 is considered acceptable (analogous to 1x10-6 for cancer).  Our monitors show Hazard of 37 or 46.  What does this mean? Is it unacceptable?  Is it halfway between acceptable or unacceptable? We don't understand the significance of this number. 

The response stated: Unlike the typical cancer risk range used in risk management decision making (i.e.,  1x10-4 to 1x10-6), there is no commonly used equivalent noncancer "allowable risk range" under Clean Air Act Section 112 (Hazardous Air Pollutants).  Based on the definition of the reference concentration or RfC (the toxicological value used to represent chronic noncancer inhalation toxicity potential), an HQ less than or equal to one indicates that adverse noncancer effects are not likely to occur, and thus can be considered to have negligible hazard.  Unlike cancer risks, however, HQs greater than one are not statistical probabilities of harm occurring.  Instead, they are a simple statement of whether (and by how much) an exposure concentration exceeds the RfC. 

Loudon County Commissioner Don Miller, task force member, said the response was "vague" to questions of health hazards.

The task force still has no clear ideas about the origin of the high levels of acrolein. 

Miller said while it seems unlikely the concentrations of acrolein found came solely from school buses, the county school system should be urged to consider retrofitting buses to reduce emissions.

"They said they have adopted an anti-idling policy already," he said.

Various measures intended to rule out a possible point source for acrolein have turned up naught. Bryan Crawford, task force member from Kimberly-Clark, said TDEC came to the Loudon plant in April to conduct stack testing, but a boiler malfunctioned and invalidated the procedure. 

Crawford said the plant, impacted by the malfunctioning equipment, received a notice of violation for particulates. 

The testing will have to be repeated and Crawford said Kimberly-Clark is eager to get the testing and results. "If the state is unable to do it, we are planning to get a contractor to come in a do it. ... We hope to institute immediate testing. We are confident we can get this resolved."

Because of scheduling problems, it will likely be late July before new tests are completed, Crawford said.

However, in reference to acrolein emissions, Crawford added, "With all the data we have seen, we are fairly confident we are not the smoking gun. We're expecting acrolein to be very low." 

Crosby said, "And so, the search goes on."