Union Pacific Railroad Superfund Site in The Dalles. This map shows the approximate location of the shoreline cap, remediation sites in River front Park and the bulk of contamination from the AmeriTies creosote tie treatment plant in The Dalles, which has been a Superfund site since 1990
Union Pacific Railroad Superfund Site in The Dalles. This map shows the approximate location of the shoreline cap, remediation sites in River front Park and the bulk of contamination from the AmeriTies creosote tie treatment plant in The Dalles, which has been a Superfund site since 1990

Dioxin in The Dalles

In 1991, an investigation by Union Pacific Railroad found dioxin, industry’s most dangerous pollutant, in the soil at its heavily contaminated Superfund site in The Dalles.

But the railroad giant inexplicably aborted its dioxin investigation almost before it started. We still don’t know whether dioxin contamination at the site seeped into groundwater or the nearby Columbia River, where it has been found in fish.

Today, nearly 30 years after the cleanup began, more than 70 percent of the contamination still remains on site. That means it’s still possible to locate at least some of the dioxin and determine whether it poses any kind of threat.

In response to inquiries by Cascadia Times, a representative of four Indian nations in the Columbia Basin -- each with treaty rights to the contaminated fish -- called for a “comprehensive investigation” into what happened.

Residents of The Dalles fish off the dock at Riverfront Park. Sediments in the Columbia River near the dock have been contamination by pollution from a creosote plant located on shore. The river is home to salmon, steelhead and sturgeon.
Residents of The Dalles fish off the dock at Riverfront Park. Sediments in the Columbia River near the dock have been contamination by pollution from a creosote plant located on shore. The river is home to salmon, steelhead and sturgeon.

by Paul Koberstein and Jessica Applegate
Photos by Sarah Clark

July 23, 2018

As we head into summer, people will be dipping their toes into the cool waters of the Columbia River, which carry an invisible load of toxic chemicals. And people may be ingesting those chemicals whenever they eat fish from the river.

A 2009 study funded by four Columbia River Indian Tribes, through the Columbia River Intertribal Fish Commission (CRITFC), found 92 toxic chemicals in fish caught in the river, including dioxins, furans, PCBs, arsenic, mercury, and DDE, a toxic breakdown product of DDT.

All of these chemicals are a threat to human health, especially dioxin, the most carcinogenic pollutant emitted by industry.

Although it’s impossible to trace all of this pollution back to its source, an archive of 5,500 pages of mostly technical documents released in May by the Oregon Department of Environmental Quality points to a heavily contaminated railroad tie treatment plant located right next to the river in The Dalles.

This article is largely based on Cascadia Times’ review of those documents.

The documents show that during nearly a century of dousing railroad ties with creosote and other chemicals, Union Pacific and its corporate partners contaminated an 83-acre site with a vast array of toxic chemicals, including dioxin.

But little is known about the extent of dioxin contamination at the site. Under the supervision of the DEQ, CH2M Hill, a Union Pacific contractor conducted only a superficial search for the pollutant. In 1991, it located a dioxin deposit near the tie treatment plant some 500 feet from the river, but it never looked for dioxin again anywhere else on site.

Most significantly, it failed to check for dioxin in the groundwater or in Columbia River sediments, even though it had been found at other railroad tie treatment sites elsewhere in the United States.

In particular, DEQ didn’t bother look for the most dangerous type of dioxin -- a substance known as 2,3,7,8-tetrachlorodibenzo p-dioxin (TCDD).TCDD, an impurity found in the Vietnam-era defoliant Agent Orange, is about 2500 times more carcinogenic than hexavalent chromium, the highly toxic compound made infamous by the movie Erin Brockovich.

Cascadia Times reached out to DEQ and Union Pacific multiple times for comment on issues raised in this article. Neither has responded.

Dioxin in the Fish

To this day, DEQ continues to assert that dioxin at the site was never a threat, a view that it based on only a limited amount of information, and a view that Indian tribes do not share.

“We strongly urge DEQ to conduct further investigation,” said Chuck Hudson, spokesman for CRITFC, a Portland-based group that represents the Warm Springs, Umatilla, Yakama and Nez Perce tribes. He said news of the dioxin contamination came as a surprise to him even though he has been at the agency for nearly 20 years.

“The limited testing done to date coupled with the Columbus, Mississippi, experience fully warrant additional work.  While the risk is heaviest on resident fish consumers there is risk borne by our tribal members living and fishing for salmon in the immediate area.”

Hudson was referring to a town in Mississippi where EPA linked a massive amount of dioxin contamination to a similar tie treatment plant. An investigation in Columbus found dioxin in kitchens, attics and even in the blood of residents.

Moreover, the seven types of dioxin found in the blood of people living near the tie treatment plant in Mississippi matched exactly the seven types of dioxin found in Columbia River fish.

The tribes have much more than a passing interest in the health of the fish as well as the land polluted by Union Pacific. In the Stevens Treaty of 1855, they ceded the land to the United States, but reserved the right to fish. They view contamination of the fish as inconsistent with their treaty rights.

“Given the broad area, both on land and river bottom, known to be impacted by the decades of contamination a comprehensive investigation is needed,” Hudson said.

The site has been contaminated sInce 1923, when Union Pacific and its corporate partners began treating railroad ties there with creosote and other chemicals, releasing an unknown about of contamination in the process. Thirty years ago, the railroad began cleaning it up, a job that it does not expect to complete for several more years.

Union Pacific has pumped more than 120,000 gallons of a dense toxic goo from aquifers located several hundred feet under the ground. There’s some urgency to the job: these aquifers drain their contents into the nearby Columbia, possibly contaminating fish as well as unsuspecting windsurfers for decades.

“It’s unacceptable for the government to take decades to cleanup toxic sites, when people are using the Columbia River every day,” said Lauren Goldberg, a staff attorney for Columbia Riverkeeper, a citizens group that advocates for the protection of the river.

“People rely on the Columbia for drinking water and fish,” she continued. “They take their kids down there to swim. People flock to the Columbia on a hot day to enjoy time with family and friends. The corporate interests do not have the right to take away a river that people deeply value and enjoy.”

A large amount of the contamination still remains on site. By the time the cleanup work is completed at some uncertain future date, only about 30 percent of the total amount of contamination will have been removed, said David Anderson, an environmental cleanup manager at DEQ. He said the remaining 70 percent will remain in place because it is immobile, caked onto rocks beneath the ground, or trapped within porous boulders. At that point, he said, it should pose no further threat to people.

A discarded railroad tie is found on the beach of the Columbia River at Riverfront Park in The Dalles.
A discarded railroad tie is found on the beach of the Columbia River at Riverfront Park in The Dalles.

Dioxin in the dirt

In 1990, the US Environmental Protection Agency added the Union Pacific site to its Superfund list of the nation’s most polluted places.

The list of active Superfund sites on the Columbia River includes the nuclear-waste riddled Hanford site -- the most contaminated waste site in the western hemisphere -- located about 150 miles upstream from The Dalles. The Union Pacific site is one of 13 Superfund sites in Oregon and 1,337 in the United States.

A number of companies have operated the tie treatment plant over the years, including Kerr-McGee and the current operator, AmeriTies West. Today, the plant emits toxic air pollution which some residents of The Dalles say is making them sick, as Cascadia Times reported in May.

Their health complaints were dismissed by the federal Agency for Toxic Substances and Disease Registry (ATSDR) in a Health Consultation Letter released to the pubic last month. But an investigation by Cascadia Times found significant gaps in ATSDR’s analysis.

This spring, while Cascadia Times reporters were looking into the plant’s air pollution, an anonymous tip triggered a focus on dioxin, the most carcinogenic pollutant emitted by industry, according to this EPA list .

Dioxin is a group of several hundred different chemicals featuring chlorine atoms attached to hydrocarbons, a basic design common to a class of dangerous chemicals that includes nerve gas, DDT, polychlorinated biphenyls (PCBs) and a wood treatment chemical formerly used at the Union Pacific site known as pentachlorophenol.

At first blush, the documents released in May by DEQ did not appear to confirm the presence of dioxins at the site. For example, a 1996 document known as a “Record of Decision,” which lays out a cleanup plan that’s still in effect today, makes no mention of dioxin. Nor do a series of consent agreements requiring Union Pacific to pay for the cleanup. A DEQ fact sheet published in 2016 also says nothing about dioxin.

But after digging deeper into the archive, it quickly became clear that dioxin had in fact been found. We found a few details about this discovery in a 1,800-page

document entitled, “Final Remedial Investigation Report,” which was prepared for Union Pacific by the engineering firm CH2M Hill in 1993.

Starting in 1989, CH2M Hill collected hundreds of samples from the site, according to this report. It found the site’s worst contamination under a pond where over the years the plant had dumped unknown quantities of wastewater and other toxic chemicals.

In samples collected in 1990, CH2M Hill found that the pond had been heavily contaminated with several carcinogenic chemicals, including pentachlorophenol, naphthalene, and polycyclic aromatic hydrocarbons.

Pentachlorophenol, also known as penta, was the primary wood treatment chemical used at the plant beginning in 1950, shortly after the pesticide was initially brought to market. The plant used penta until 1987, when the EPA restricted its use because of its potential to harm the health of people exposed to it.

Commercial-grade penta is contaminated with trace amounts of dioxin, according to EPA.

In 1991, CH2M Hill re-sampled the soil twice at depths of 3 and 11 feet under the pond. An analysis showed the samples tested positive for three types of dioxin, including hexachlorodibenzo-p-dioxin (HxCDD); heptachlorodibenzo-p dioxin (HpCDD); and octachlorodibenzo-p-dioxin (OCDD).

EPA says dioxin type HxCDD is 100 times more carcinogenic than hexavalent chromium, the highly dangerous pollutant found at many industrial sites around the United States.

But DEQ made no apparent effort to locate a much more dangerous type of dioxin, TCDD, a compound that can damage a person’s health on immediate contact. As we’ve pointed out, TCDD contamination has been found at railroad tie treatment plants in other states.

The collection of the two soil samples marked the beginning and end of the search for dioxin. No other samples were collected or analyzed for the pollutant anywhere on site.

David Anderson, a DEQ cleanup manager at the site, said DEQ was not concerned about dioxin contamination at the site because concentrations in the soil samples were not high enough to harm people.

But if TCDD had been found, the site would have posed a much greater health threat, the documents show. But the search for dioxin was prematurely aborted before TCDD could be found.

Dioxin in the Water

We know there’s dioxin in the Columbia River, and we know the tie treatment plant in The Dalles is one possible source.

The contaminated water under the ground at the Superfund site flows into the Columbia. CH2M Hill found penta among many other toxic chemicals several hundred feet below ground. Some penta and quite probably dioxin was found in a well built near the plant in 1957. Union Pacific abruptly abandoned the well because of the contamination.

The City of The Dalles occasionally draws drinking water from a nearby backup source known as Lone Pine Well. Located east of the Superfund site, Lone Pine’s water source is “upgradient” from the contamination and is not threatened by it, according to DEQ.

For many years, the plant pumped contamination directly into the Columbia River via a stormwater pipe out 150 feet from the shore. Built in 1937 by US Army Corps of Engineers, the pipeline also discharged toxic chemicals into Riverfront Park next to the river.

In 1967, the Army Corps began hearing reports of oil sheens surfacing in the Columbia near the end of the pipe. Four years later, it plugged the pipe with concrete. But no one ever analyzed the contents of the pollution for dioxin.

In 1994, Union Pacific found that the pollution contaminated about 1.4 acres of Columbia River sediments as far as 300 feet from shore and down to a depth of 4 feet. Sediments contained elevated levels of penta, arsenic and several other carcinogenic compounds, including naphthalene, the main pollutant in the plant’s noxious air emissions.

A year later, Union Pacific covered the contaminated river sediments with a cap consisting of several layers, including a fabric lining, a layer of gravel, and riprap. Although the cap has eroded significantly over the years, often during major floods, DEQ reports say it still covers all of the contaminated sediment. Union Pacific has agreed to continue monitoring the cap far into the future.

Meanwhile, in 1992, Union Pacific removed about 2,450 cubic yards of “heavily contaminated” soils from Riverfront Park containing penta, PAHs and arsenic.

The park includes a seasonal wetland area. Union Pacific found surface contamination in the northern of part of the park which is used by migratory birds. In 1984, Union Pacific donated the park to the city, which began developing it for public use two years later.

Union Pacific has yet to remove contaminated soils close to the plant in the general area where CH2M Hill found dioxin 28 years ago. DEQ says it has allowed the railroad to defer cleanup of these soils to some future unknown date “because the plant is still operational and there is no current potential exposure risk.”

Dioxin in the Blood

It’s not unusual for Superfund sites to be contaminated with penta as well as dioxin. ATSDR says wood treatment plants have contaminated about 250 communities around the country.

One of these, a Superfund site in Columbus, Miss., was home to a tie treatment plant similar to the one in The Dalles. Just before the Columbus plant closed in 2003, both penta and dioxin contaminated the site and the surrounding neighborhood, according to the EPA. In 2000, toxicologists found dioxin in the kitchens, attics and even bloodstreams of nearby residents.

In all, they found seven types of dioxin in the blood of people in Columbus, including the dioxin compound TCDD.

As previously noted, the same seven types of dioxin found in the blood of Columbus residents have also been found in fish caught in the Columbia River downstream from the Union Pacific Superfund site in The Dalles, according to an EPA study from 2002.

DEQ and Union Pacific aborted their search for dioxin in The Dalles after finding just three types of the chemical. It is not clear whether they would have found all seven types had they continued the search.

It is possible, even likely, that dioxin contamination was much greater in The Dalles than in Columbus. The Columbus plant treated wood with pentachlorophenol for 23 years, from 1951 to 1974, while the plant in The Dalles used penta 37 years.

In 1999, Columbus residents began filing lawsuits alleging that the wood treatment plant damaged their health. Their attorneys hired experts to test homes, properties and even bodies for the presence of dioxins and other toxic substances associated with wood treatment plants.

Columbus residents suffered from skin itch, headache, eye burning, sore throat, nausea, cough, and chest tightness. People in The Dalles have lodged similar health complaints.

Columbus attorneys hired Dr. James Dahlgren, a toxicologist at the UCLA School of Medicine, to conduct a battery of tests on people who lived near the plant. He found dioxin in the bloodstreams of 10 residents in Columbus.

Dr. Dahlgren also collected swipe samples from kitchens and attics.

Dr. Dahlgren, who is now retired, published his findings in 2002 in a study published by a peer-reviewed journal. ATSDR cited the study in its own evaluation of health problems related to wood treatment plant pollution.

In 2009, ATSDR noted that Dr. Dahlgren’s data showed that people exposed to wood treatment chemicals are five times more likely to develop cancer than people who were not exposed to those chemicals. in addition, they were three times more likely to suffer from bronchitis and four times more likely to have asthma.

It should be noted that Columbus residents won health damage awards totalling $62.5 million in multiple lawsuits. Residents of The Dalles have not filed lawsuits for health damages, although a case seeking property damages is now pending in a Wasco County court.

Has dioxin entered the kitchens, attics and the bloodstreams of people in The Dalles? Is dioxin in the groundwater water or Columbia River sediments? No one knows the answers to these questions.

Neither Union Pacific nor DEQ have plans to find out, and never did.


Contact Linda Hayes Gorman, DEQ east region administrator (541-633-2018) and demand a complete investigation of the contamination and cleanup of the Union Pacific Superfund site in The Dalles.

Call on DEQ Director Richard Whitman (503 229-5300) or Communications and Outreach Manager Donald Oliveira (503-229-5176) to initiate an investigation of how DEQ’s east region handles Superfund cleanup projects and public involvement.

Contact Lizz Caviness, DEQ east region public affairs director (541-633-2008) and ask DEQ to form a community advisory group to gather information and offer feedback on the Superfund cleanup in The Dalles, as it has done for the Portland Harbor Superfund site. Offer to join that group.

Tell these DEQ officials what you think. Do you support its plan to delay the cleanup of  contaminated soil at the tie treatment until some future date? Should DEQ find out whether Columbia River sediments and groundwater at the site are contaminated with dioxin?

Support the efforts by Columbia River Indian Tribes, Columbia Riverkeeper, Friends of the Gorge and The Dalles Air Coalition to preserve and protect the Columbia River.

View DEQ’s Union Pacific Superfund site documents here.


A timeline

1922- Tie Treatment plant opens on Union Pacific land in The Dalles. Nebraska Bridge and Timber Supply is the first operator.

1937- US Army Corps of Engineers builds a levee along northern perimeter of site.

1948 – The plant is flooded when the Columbia River breaches the levee.

1950 - J.H. Baxter and Company becomes plant operator. It begins to use pentachlorophenol and ammoniacal copper arsenate in addition to coal tar creosote as wood preservatives.

1957 - A well is drilled as a source for drinking water, but is not used because of groundwater contamination. The well was sealed.

1963 - Interstate 84 is built along the northern perimeter of the site.

1967-1970 - DEQ receives various reports that oil has been released into the Columbia River north of the site in the vicinity of the outfall for the pipeline.

1980 – Congress passes the Comprehensive Environmental Response, Compensation, and Liability Act, known also as Superfund.

1984 – Union Pacific donates Riverfront Park to the city of The Dalles. EPA issues a Preliminary Site Inspection Report for the site. DEQ begins to study contamination at the site.

1987 - Kerr-McGee purchases plant buildings, while Union Pacific retains ownership of the land. Use of pentachlorophenol is discontinued.

1990 - EPA adds the site to its National Priority List of Superfund sites.

1993 - DEQ releases 1,800-page Remedial Investigation Report.

1995 - Union Pacific builds a cap over contaminated sediments in the Columbia River.

1996 – DEQ issues “Record of Decision,” a document that guides cleanup of the site.

1997 – Union Pacific signs a consent decree under which it agrees to pay for the cleanup.

2005 – Kerr McGee sells the plant to AmeriTies West LLC. Union Pacific continues to own the land.

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