LOWER PROVIDENCE — Superior Tube has applied for permission to increase the amount of volatile organic compounds it emits from its Germantown Pike plant.
However, the substance being emitted remains far less dangerous than the recognized carcinogen the company used previously, according to state regulators.
In fact, according to Lynda Rebarchak, spokeswoman for the Pennsylvania Department of Environmental Protection's (DEP) Southeast office in Norristown, the requested increase of nine tons per year is a direct result of the company's decision last year to completely abandon trichloroethylene, or TCE, in its industrial processes.
In order to give up on TCE, the company had to spend about $100,000 to change over its equipment and use a different chemical, called n-propyl bromide, or nPB for short, in order to degrease the tubes it manufactures there.
Like TCE, nPB is considered a "volatile organic compound," or VOC.
But more significantly, nPB is not considered "a hazardous air pollutant," a category which, as a recognized carcinogen, TCE falls squarely into.
"To us, it's a big distinction" between TCE and nPB said Rebarchak.
After several months of operation, the company discovered it needed to use more nPB than it had originally estimated. However, the increase Superior Tube is seeking remains far below the limit set by the plant's overall permit, said Rebarchak.
In addition to a permit for the plant's overall emissions, Rebarchak explained, the DEP also requires permits for each individual machine that emits pollutants.
In May, Superior Tube applied for permission to increase nPB emissions from two of its machines. Although the requested increase adds up to nine tons, Rebarchak said it will remain far below the overall 166 tons the facility is allowed to emit into the air.
Following on the heels of a 2,400 TCE spill on July 10, 2007, an accident which cost the company a
$35,000 fine from the state, Superior Tube began moving toward eliminating the substance completely from its procedures.
Last February, it announced the change.
The change was significant because of the elevated levels of TCE being measured in the air in the Collegeville-Trappe area at the time.
In addition to Superior Tube, the Accellent Plant in Trappe — once known as Universal Tube — is also located in the area. Accellent still uses TCE as a de-greaser, but has installed carbon filters which sharply cut back on the amount that escapes into the area.
Since the two companies — once among the largest TCE emitters in the nation — had made the changes, the DEP began seeing TCE levels in the region's air continue to drop.
By comparison, nPB is considered much less dangerous than TCE.
According to the Federal Register listing on May 30, 2007, nPB is a "nonflammable organic solvent with a strong odor."
The Environmental Protection Agency, which studied the chemical, determined "nPB can be used (as a TCE alternative) with no substantial increase in overall risk to human health and the environment."
The EPA also determined nPB is "less persistent in the environment than many solvents," is less toxic to aquatic life than TCE and does not "bioaccumulate," meaning its concentrations do not rise as it moves up the food chain.
None of which is true of TCE, which the EPA considers to be a "potential carcinogen" and which the state of California considers to be cancer causing.
Which is not to say nPB poses no risk. According to the Federal Register listing, some studies have suggested "severe, possibly irreversible neurological effects from exposure at sustained concentrations of 100 parts per million or greater."
Other studies suggested a possible connection between nPB and menstrual disorders and sperm motility; however the EPA did not find any of those studies to be conclusive.
In fact, in issuing the current nPB rules, EPA dropped a proposed exposure limit of 25 parts per million suggested in its draft regulations.
"We believe that proper use of nPB in solvent cleaning would not pose measurable risks to the general population," the EPA wrote last year.
However, some local leaders want a public hearing to air out the issue.
Supervisor Rick Brown said he would urge the supervisors to comment on the proposed change and formally ask the DEP for a public hearing on the matter.
"They are planning to put more than nine tons of volatile organic compounds into the air," Brown said. "We need to find out how this will affect people."
Brown said seven neighbors of the plant had told him they want to have a public hearing.
Should no public hearing be held, Rebarchak said a decision on Superior's request would probably not come before "mid-December, depending on how many comments are received."
A complete copy of Superior's application is available for public review at DEP's Southeastern Regional Office, 2 E. Main St., Norristown.
Written comments or requests for a public hearing should be made to Francine Carlini, Regional manager Air Quality Department, Department of Environmental Protection Southeast Regional Office, 2 E. Main St., Norristown, PA 19401.