PCBs near OMSI may be capped for safety
State environmental regulators are scrutinizing a cleanup plan by Portland General Electric that proposes to cover rather than dredge and remove two PCB-laden sites in the Willamette River bottom next to the Hawthorne Bridge and Tilikum Crossing.
The northern site lies under a popular dock used by dragon boaters, kayakers and collegiate crew teams, and adjacent to a riverfront stretch the nonprofit Human Access Project hopes to convert to a public beach. (See related story on page 1 of Sustainable Life.) The southern site is offshore from the Oregon Museum of Science and Industry and the Portland Opera building, near the new light-rail bridge.
PGE, whose past industrial operations are suspected of causing some of the contamination, proposes to use isolation caps at both sites, essentially layers of sand and rock that seal off the toxic materials from fish and invertebrates. PGE reasons that isolation caps, which will cost an estimated $3.1 million, are safer than removing contaminated sediment and shipping it to a hazardous waste dump, pegged to cost $5 million.
When you want to remove the sediment you have to dredge it and in the dredging, you spread it, says Arya Behbehani, PGE general manager for environmental and licensing services. Itll go and settle somewhere else and youre back at square one.
Isolation caps can be designed to last 200 years, Behbehani says. A comparable cap installed by PGE in 1992, where the OMSI USS Blueback submarine is located, withstood the massive 1996 flood of the Willamette, she says.
Tom Gainer, Portland Harbor project manager for the Oregon Department of Environmental Quality, says dredging can be done safely so it doesnt spread contaminants. However, the agency agrees capping could be the most effective solution at those two sites, Gainer says, and he expects DEQ will recommend modifications to PGEs plan rather than wholesale changes. I think ultimately we will wind up with a cap thats acceptable to DEQ, Gainer says.
DEQ confirmed both sites were contaminated in a 2008 study of more than 100 soil samples in the downtown reach of the Willamette. Neither site is as heavily contaminated as the toxic parts of the 11-mile-long Superfund site to the north, in the Portland Harbor. But DEQ wanted to address the downtown stretch first, so chemicals dont drift downstream and re-contaminate the Superfund site, says Keith Johnson, DEQ cleanup program manager.
PGE stepped up to oversee studies and issue a 525-page recommended cleanup plan, plus a one-inch-thick supplement submitted in May. We recognize that we have a connection to the area, as do others, says PGE spokesman Steve Corson.
PGEs consultant, URS, found the sites were polluted by several toxic materials: PCBs, dioxins, DDT, chlordane, mercury, arsenic, lead and polycyclic aromatic hydrocarbons or PAHs, among others. But PCBs, or polychlorinated biphenyls, are the biggest concern, Gainer says.
Production of PCBs, which were widely used in coolant and heat transfer fluids, was banned in the United States in 1979. Tests showed they can cause cancer in humans, as well as endocrine disruption and neurotoxicity. They generally attach to the sediment in the bottom of the river, and pose the most danger to nonmigratory fish and invertebrates that feed locally. The main danger to humans is from eating too much fish caught in the
There is a lesser risk of having it exposed to your skin, Gainer says. However, humans dont have much direct contact with the sediment at the river bottom.
PGE had operations at the Hawthorne Building, located two blocks east of the northern site, starting in 1908, using it for a transformer shop and line crews, Behbehani says. Until the 1960s, drainage from that building went into a city storm drain that fed directly into the contaminated site. Then, in 2006, a fire burned down much of the nearby Rexel Taylor building, and a PGE electric pole that included three transformers caught fire. Those contained PCBs, which likely drained into the river as firefighters put out the fire.
The URS study documented that spills in the area also could have come from other past industrial uses, and the city outfall pipe, as well as contamination getting into the river from vehicles on the Marquam Bridge upriver. URS proposed a 38,350-square-foot cap over that site.
The worst contamination is where the city pipe drains into the river, so the Portland Bureau of Environmental Services may be one of the other parties that might be asked to shoulder some of the cleanup costs.
The southern site is near PGEs former Station L, a power generating station on land later donated to OMSI. The utility operated a fuel-receiving dock in the river from about 1957 to 1994. The science museums Turbine Hall is a surviving remnant of the old PGE building. Once again, other contributors are thought responsible for pollution there as well. URS proposed a 56,890-square-foot cap over the southern site.
PGE can be held liable for pollution its operations caused even when it sells its buildings, so it seeks to clean them up before selling them, as is being done with the Hawthorne Building, So we take great care that we do things right, Behbehani says.
Get a jump on it
Neither site rises to the level of pollution found common in the Portland Harbor, where shipbuilding, DDT manufacturing and other industrial activities were conducted for decades. However, the two sites are closer to more human activities, notes Travis Williams, executive director of Willamette Riverkeeper.
The Rivers East Center is located on the waterfront next to the northern site, and its home to Willamette Riverkeeper, Alder Creek watercraft rentals, Rose City Rowing Club and the Portland Boathouse, among others. The dock there is used by several groups to launch vessels into the river, including the Rose City Rowing Club, the Wasabi Paddling Club, and the Portland State University and University of Portland crew teams.
Williams says hes comfortable with capping rather than removing the contamination there, given the sites small size and location. It makes a lot of sense to jump on it and get it done, he says.
Willie Levenson, ringleader of the Human Access Project, has been working for three years to clear rocks and other obstructions from a slice of riverfront due south of the Hawthorne Bridge, downhill from the Vera Katz Esplanade. Levenson says DEQ toxicologists and others assure him the river is perfectly safe to swim in now. However, he is anxious to see the PCB contamination addressed, and is pleased with the cooperation so far by PGE and the DEQ.
Im excited to see something happening, Levenson says.
Gainer says hes already prepared some draft comments on PGEs cleanup plan and expects to deliver them formally soon. He hinted that one area of disagreement may be on the size of the caps, with DEQ seeking a larger footprint than the ones proposed by PGE and URS.
Once DEQ approves a final cleanup plan, the state agency would have to negotiate another agreement with PGE to take responsibility for doing the work. PGE, if it fulfills that role, then would have the option of seeking contributions from others believed partly responsible for the pollution. Securing money from other responsible parties would not be up to DEQ, Gainer says.
In contrast to the federal Superfund process, which is dragging on with no cleanup in sight, state regulators hope the two sites near downtown can be cleaned up in 2015.