Schulle said that the Fire Department last week sent him an updated report on the EPA's investigation that sheds some light on the situation.
According to the report, the chemical fumes are coming from contaminated soil under the station, Schulle said. Information from the EPA's tests indicates the chemicals are petroleum-based.
It's not clear, however, how the soil became contaminated.
Another document in the report, an email chain between a city health-and-safety specialist and the EPA, rules out underground storage tanks from two nearby gas stations as a possible source: The specialist writes that the tanks "appeared to be intact" when they were tested, according to Schulle.
At this point, the union leader said he just wants progress.
"One of our concerns, as the temperature warms, is that these levels are going to rise," he said. "I'd rather see them eliminate the source entirely, along with any further concern."
The EPA initially told the department and union that the levels were in the "acceptable range" and that the station could remain open, but Fire Commissioner Lloyd Ayers told the Daily News in January that the department elected to close the station anyway, rather than risk further injury.
Capt. Clifford Gilliam, a spokesman for the department, confirmed that the source of the fumes hasn't been identified, and said that the station is closed until "further notice."
In the time that Engine 66's crew has spent at its new home at Engine 39, about a mile away on Ridge Avenue near Cinnaminson Street, it has responded to several fires without incident, Gilliam said.
Meanwhile, Schulle says he's researching ways to mitigate the fumes in order to expedite reopening the station.
"Our concern, over a period of time, is that we don't know how long these guys were exposed to these chemicals, some of which are carcinogens," he said.
"If our guys are going back into the station, we want to ensure these chemical levels are at zero."
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