Health experts say PCBs at landafill would be minimal risk
East Carbon officials and citizens received a positive recommendation at Tuesday's council session concerning ongoing plans to allow polychlorinated biphenyls into the local ECDC Environmental landfill. During the session, Carl Farley, an independently hired industrial hygienist from Greenleaf Americas detailed ECDC's current permit application with the EPA and the potential risks PCB transportation could have on the small Carbon County community.
The bottom line of Greanleaf's assessment, which was given by both Farley and an Environmental Protection Agency medical expert, Dr. Steve Thygerson, stated that a "worst case scenario incident at ECDC was unlikely to pose significant human health risks to area residents from airborne PCBs."
Farley's presentation focused on air emissions from the material transfer cell at ECDC rather than housing of the material, which will be monitored by the EPA exclusively. Air emissions were reviewed in three steps: a hazard recognition of issues which could arise from exposure to PCBs; an exposure assessment; and a risk characterization of the worst case scenario in the event that an accident or incident were to take place during transport of PCB-laden material at ECDC.
As for hazard recognition, Thygerson reported that PCBs are a probable human carcinogen which can cause the eruption of blackheads, cysts and pustules known as chloracne as well as irritation to the ears, nose, throat and lungs at high doses.
According to the EPA physician, these high doses will not be present at ECDC. In fact, he showed a thousand times difference between what the EPA considers to be a hazardous amount of PCB contamination in airborne dust and the amount which could be released during material transfer at ECDC.
"It's a thousand pound gorilla vs a one-pound gorilla. That is pretty much what we are talking about here," commented Thygerson, when asked to put the airborne particulate figures in layman's terms. "Another thing that is not built into this model is the distance from East Carbon to ECDC's transfer area. These figures represent East Carbon being right next to ECDC. So we could even say these figures were for the employees of ECDC."
Farley explained the numbers even further based upon the 500 ppm limit which is defined in ECDC's application parameters.
"Lets assume that all of the dust in this area was laden with 500 ppm of PCB contamination, and someone was breathing it all day every day of their lifetime. Are they going to exceed the total daily intake limit below which we don't see any health effects? And the answer is, no we are not going to exceed it. In fact, we are 1,000 times below it, so good news."
ECDC's application does includes several PCB-laden materials including but not limited to environmental media, soil and gravel, dredged materials, sediments, settled sediment fines and aqueous decantate from sediment as well as sludge. PCBs are also found in transformers, capacitors, pumps, pesticide extenders, sealants in caulking and wood finishing, waterproofing agents and carbonless copy paper. While the landfill will receive materials which are contaminated with PCBs at up to a 500 parts per million limit, they will not be allowed to receive straight PCB liquid solutions, such as the material that would drain out of a used transformer.
Following the Greenleaf presentation, local resident Paul Martinez, who owns property and livestock directly across the road from ECDC, expressed concerns over the health risks posed by PCB exposure.
"What you didn't mention in your report was the malignant melanoma as exposure to dusk particles on the skin, what are the studies concerning this risk? And why didn't you touch on that," asked Martinez.
According to Farley, dust particles on the skin would not be high enough in concentration to cause any problems.
"The skin problems we have seen in case studies have to do with occupational exposure, workers that are up to their elbows in this stuff and they get it. You are exactly right, there is skin irritation, chloracne and other effects," said Farley. "What I'm saying is that dust exposure has not caused skin issues, liquid has."
To clarify at this point, ECDC officials reiterated that they would not be accepting the liquid material which has caused malignant melanoma issues.
While the Greenleaf assessment was positive toward ECDC's current application model, they did raise some issues with the permit application. For instance, EPA permit specs require "thick, relatively impermeable soil at the dump site." Soil at ECDC is relatively permeable, according to Farley. However, synthetic membranes may be used as an alternative. The EPA also requires the bottom of the landfill be greater than or equal to 50 feet from the historical high water level. ECDC has requested a waiver from this particular point, justifying that their synthetic membrane lining system provides better than adequate containment.
The Greenleaf final recommendations also ask that ECDC: redesign the construction of their rotary facility dump floor to allow for liquid and sludge containment, collection and removal. This would ensure that dump trucks entering/exiting the rotary facility do not track PCB laden waste out.
They also asked that ECDC officials avoid aerosolizing PCB laden wastes by ensuring means of examining - and wetting if necessary - waste prior to dumping. Finally, Greenleaf recommended that ECDC not use PCB-contaminated leachate as dust suppression within Toxic Substances Control Act or TSCA waste cell.
Under the permit application, ongoing air monitoring at ECDC would be conducted by a third party independent source and would be be conducted during all PCB operations at least until adequate baseline levels are achieved.
The possible intake of PCBs at the landfill will not only cause the construction of a new "TSCA cell," the contract between ECDC and the city concerning tippage fees will also be modified. Following the Greenleaf presentation, city attorney Jeremy Humes discussed the fact that any intake of the new material would cause the city's fee to increase from $1 per ton to $1.50 per ton under contract revisions brought forward by ECDC.
The city also has made proposed changes to the contract and as fee changes were brought forward with council moved into executive session, leaving the chance for any change until a following meeting. Any change in the city's contract would require that the municipality's bond holders be made aware of the change.