Lawmakers look at potential penta problem

Editor's note: This story has been changed to add information about an error in the 2015 U.S Fish and Game ground contamination study near HEA powerlines. 


Leglislators are debating a bill to exempt utilities from legal liability for chemicals used to treat wooden poles, prompted by possible soil contamination around Homer Electric Association (HEA) powerline poles following the Kenai Spur Highway north of Sterling.

Sen. Peter Micciche (R-Soldotna) sponsored the proposal, Senate Bill 173, with a companion bill, House Bill 334, sponsored by Reps. Mike Chenault (R-Nikiski), Adam Wool (D-Fairbanks), and Chris Tuck (D-Anchorage).

The HEA powerline in question is in the Kenai National Wildlife Refuge, where Refuge Deputy Manager Steve Miller said staff noticed apparently dead vegetation around the base of the poles. Miller said HEA’s permit to cross the Refuge, from the Refuge’s parent agency, the U.S. Fish and Wildlife Service, specifies a distance from the base of the poles beyond which substances shouldn’t reach. In 2015, Fish and Wildlife sent toxicologist Lori Verbrugge to sample surface soil around 12 of the poles. She found levels of pentachlorophenol — a heavy-duty wood preservative often shortened to “penta” — greater than the U.S. Environmental Agency’s allowed amounts.

Wooden utility poles can have useful service lives of up to 60 years, thanks in part to chemicals like penta, which is applied to kill ants, termites, and rot-inducing fungus. Penta permeates about 36 million wooden poles nationwide according to the EPA, and about 250,000 in Alaska, according to Micciche’s testimony on SB 173 to the Senate Resources and Senate Judiciary Committees. Though the U.S Environmental Protection Agency permits penta as a wood preservative under the Federal Insecticide, Fungicide, and Rodenticide Act (FIRFA), it restricts previous uses as an insecticide and herbicide.

The EPA most recently examined the potential health effects of penta in 2008, when it reregistered the chemical under FIRFA and ruled that it “will not pose unreasonable risks to humans or the environment” if properly applied as a wood preservative, but that “a reasonably strong argument can be made that exposure to pentachlorophenol is associated with increased risks of a number of diseases. … Based on the evidence collected to date, careful control of exposures to chlorophenols, including pentachlorophenol, is certainly warranted.”

It’s unknown whether that disease risk comes from penta or other chemicals that appear within it — specifically, dioxins and furins, two toxic substances created as byproducts of penta’s manufacturing process that may be more toxic than penta itself, Verbrugge said.

“If you look at the structure of pentacholorophenol, you’ll see that if you put two of them together, kind of like puzzle pieces, it’d be a dioxin,” Verbrugge said. “It’s a trace contaminant, but they’re so toxic that even though they’re only there in trace levels, they turn out to be the toxicity driver.”

Verbrugge’s findings from the soil samples are awaiting peer review and haven’t yet been published. However, in a January 2016 letter informing the Alaska Department of Environmental Conservation (DEC) of the findings, Kenai Wildlife Refuge Manager Andy Loranger wrote that the study had found “that a majority of poles treated with (penta), both historically (1950s) and more recently (within the past 20 years) have contaminated surrounding soils with concerning levels of (penta) and dioxins/furans.”

After recieving Fish and Wildlife’s analysis, Program Manager John Halverson of DEC’s Contaminated Sites program requested that HEA investigate the extant of the contamination in a May 2016 letter.

In soil 50 centimeters from the base of the poles, Verbrugge’s study found pentachlorophenol concentrations “on average 3-4 orders of magnitude above the (EPA’s) risk-based screening levels,” Halverson wrote — an average concentration of 18 parts per million, versus EPA standards of 2.1 parts per million. Dioxin concentrations, Halverson wrote, “were on average 3-4 orders of magnitude above the risk-based screening levels at 50 cm from the poles.”

“As the owner of the poles, HEA is responsible for any contamination that may have resulted from their use,” Halverson wrote.

HEA questioned both the Fish and Wildlife findings and the need for further study that DEC requested. HEA Environmental Compliance Officer Bruce Linton responded that “power poles and adjacent soil are not a hazardous waste and do not require cleanup or characterization.” Linton also wrote that contaminant levels “may actually be significantly (orders-of-magnitude) over reported by the (Fish and Wildlife Service)” and that HEA had found “what appear to be significant flaws in the reported test results putting the entire data set into question.” These included one measure of chemical concentration that ranged up to 8.1 million parts per million, according to Linton’s letter (Verbrugge wrote in a later email that this was a measurement unit error made by the testing laboratory, corrected in current drafts of the study). 

“The (Fish and Wildlife Service) soil data, although qualitative at best, confirms common knowledge that wood treatment constituents routinely transfer from the wood pole into the soil adjacent to the pole, and that the effect is limited to a few tens of inches from the pole, but does not indicate mobile contaminant migration,” Linton wrote.

In a Feb. 12 Senate Resources Committee hearing on the bill, HEA General Manager Brad Janorschke said that if HEA was required to decontaminate the power pole areas, they would have to excavate, bag, and ship the soil to the Lower 48 to be cleaned in processing facilities which don’t exist in Alaska — putting the cost at around $30,000 per pole. Since HEA is a publicly-regulated utility and member-owned cooperative, the cost may fall indirectly on its members — a fact Micciche cited in his sponsor’s statement for the bill.

“The bottom-line purpose of my choice to bring SB173 forward is the financial protection of nearly every Alaskan ratepayer who depends upon a utility to deliver electricity to their home, business or facility,” Micciche wrote.


Verbrugge’s study compared levels of penta, dioxins, and furans around the poles to EPA standards, but did not look at actual environmental effects the chemicals may have had — a question that remains unresearched and which Verbrugge called “an interesting and important next step.”

“The first thing we’d need to know: have either humans or ecological receptors been exposed to these contaminants, are they actually picking them up from their environment or not?” Verbrugge said. “For it to be toxic, there has to be exposure to it, so that would be the first question — is anybody being exposed to it? And if so, at what levels? And then looking for the effects.”

At the Senate Resources hearing, DEC Director of Spill Prevention and Response Kristen Ryan said that how penta leaches from wooden poles “depends on the technology used to manufacture the pole, and the environment that it’s in.”

“That is a varied question, and something (DEC) is getting data on right now — to see what are the dynamics in Alaska’s environment related to utility poles in wetlands, and if we have anything different occurring up here versus what happens in the rest of the U.S., which is that very little leaches off if it’s been treated correctly at a manufacturing plant where they use specific technology that reduces the amount of leaching,” Ryan said.

The Alaska Department of Transportation (DOT) is presently working on the stretch of the Spur Highway were Verbrugge found contamination. Part of that work involves removing some of the poles, and DOT agreed to have a contractor carry out the analysis that Halverson had requested of HEA. Halverson said DOT plans to do that work this winter.

Janorschke told Senate Resources that DEC is also asking members of the the trade group Alaska Power Association to confer on best practices for handling, storing, and disposing of chemically-treated wood poles, similar to an effort carried out by health agencies and utility representatives in Vermont, where in 2009 penta was found in three shallow water wells near utility poles that penetrated the water table.


In the bill’s committee hearings, senators took up the question of where responsibility for penta would fall if utilities are exempt. Speaking to Senate Judiciary on Feb. 28, Micciche said his narrow goal for the bill was to “fine-tune liability” by eliminating from state law consequence for penta ground contaminiation which he said doesn’t exist under federal law’s permitting for the chemical under FIRFA.

“The intent of this bill is not that, no matter what happens with penta from a pole, someone would be released of liability,” Micciche said. “So we’re looking for the right mix of liability that protects the normal use of penta, versus some sort of gross neglience or other spill.”

The existing Alaska code from which Micciche’s bill would exempt utilities puts liability for hazardous substance releases on the owners of the substance or of the releasing facility, or on the person responsible for transporting or disposing of the substance. Environmental lawyer David Wilkinson of the Alaska Department of Law told Senate Judiciary that other possible legal consequences for penta contamination “are likely to survive” exemption from this code, but “it’s not crystal clear” how the exemption could change them. As an example, he gave a hypothetical accussation of neglience involving a utility, which would require demonstrating “duty, breach of duty, causation, and harm,” he said.

“But when courts look to find a duty, they look to statutes,” Wilkinson said. “So there’s a question raised by (the exemption): does that alter the duty that a utility might owe to a landowner? There’s a litigation question there that might come up.”

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