Hazardous contaminants found in Molalla soil
For nearly four decades, the Oregon Department of Environmental Quality has been monitoring contamination on a former mill site, located on 5th Street, south of the Molalla library.
A cleanup is expected to take place this year or next; but before that happens, and even before DEQ selects a specific cleanup plan, the department is holding a public meeting to hear comments and answer questions. That meeting will take place on March 10 at 7 p.m. at the Molalla Adult Community Center.
Site History and Contamination
The site to-be-cleaned is part of the 91-acre Avison #1 mill site, located at 500 E. 5th St. in Molalla, where lumber was produced from the 1950s through the 1990s, according to a DEQ staff report on the cleanup.
At Avison 1, from approximately 1973 to 1983, Avison Lumber Company dipped wood in a solution of 1 percent pentachlorophenol (PCP) and water to prevent mold growth on lumber being shipped overseas, per DEQ's report.
Now, both PCP and dioxins (deriving from PCP) have been found in soil on the property as a result of the dipping activities.
PCP is extremely toxic to humans, according to the United States Environmental Protection Agency (EPA), and can cause effects on the respiratory tract, blood, kidney, liver, immune system, eyes, nose and skin. It is a probable carcinogen.
Dioxins are highly toxic and can cause cancer, reproductive and developmental problems, damage to the immune system, and can interfere with hormones, the EPA reports.
So when the levels of PCP and dioxins are too high, the DEQ requires cleanup.
It should be noted that lumber was not only produced at Avison 1, but also at two other Avison mills, which are located west of the north and south parcels across South Molalla Avenue. Bill Avison sold the site of the additional mills to Floragon Forest Products, Inc. Avison said Floragon was aware cleanup would be required. But when DEQ required cleanup of that site, Floragon refused, according to Avison. So, DEQ asked Avison, the previous owner, to do that cleanup. He did so, and Avison noted that was a time-consuming and expensive process.
DEQ spokesperson Dan Hafley pointed out that Avison has worked cooperatively with DEQ for many years.
Extent of Contamination
Avison 1, still owned by Avison, is divided into north and south parcels, with the north being zoned industrial and the south being wetlands. Avison said the south parcel will remain as wetlands.
The north parcel has undergone some dioxin cleanup and will undergo more soon before it is developed.
But it is a portion of the south parcel, north of Bear Creek (and including the creek), that now requires rather intensive cleanup. The Pioneer will refer to this portion as SP1.
Avison said he does not believe the portion south of the creek requires any cleanup.
DEQ's work at SP1 began in 1983 with water sampling of Bear Creek, the DEQ report says. DEQ began taking soil samples in 1985 and has taken 76 samples between 1985 and 2015. Multiple investigations have taken place between 2004 and 2012.
Hafley noted that dioxins were known to be present as early as the 1980s at Avison.
"However, it was thought that contamination was largely addressed through removal of the dip tanks and nearby contaminated soil in the early 2000s," Hafley said.
But further investigations, he said, revealed dioxins were present on a more widespread basis.
The results, according to the report and Hafley, are as follows.
First of all, the PCP contamination found at SP1, including in Bear Creek, does not pose a risk to humans or animals. Though, Hafley did note that PCP contamination is coincident with dioxin contamination (since dioxins are derived from PCP) and so cleanup actions for dioxins will also address PCP.
Secondly, the dioxin levels in Bear Creek are also low and do not pose a risk to humans or animals based on DEQ standards.
However, the dioxin levels found in the soil at some areas of SP1 do pose a risk to both humans and animals. Avison noted the soil is covered in heavy brush and grass.
For humans, it is only trespassers who could be exposed at the site since SP1 is undeveloped wetlands. But animals living in the area could include the vagrant shrew, robin, long-tailed weasel and red-tailed hawk.
While dioxins and PCP are in both the groundwater and in Bear Creek, a tributary of the Molalla River, Hafley said it is not possible for the toxins to make their way into Canby or Molalla drinking water as the contamination is confined to the Avison 1 and Floragon sites.
Avison Lumber Company representatives will be responsible for the cleanup of SP1.
DEQ has considered several cleanup methods, based on previous investigations and a feasibility study the Avisons did in 2019. These include: "in-situ sequestration," which involves adding active carbon to the soil and then mixing the soil to distribute evenly; removal of soil and disposing off-site; capping with concrete or asphalt; excavating contaminated soil and relocating to the north parcel to be capped; and a combination of these methods. All of these options also include wetlands restoration.
The number one factor in determining which method to use is that the remedy must be protective of public health and the environment, Hafley said. DEQ also considers five balancing factors: effectiveness, implementability, implementation risk, long-term reliability and reasonableness of cost.
Currently, DEQ would like to use a combination of methods, with the worst of the contamination being removed for landfill disposal, Hafley said, and the remaining contamination isolated through either capping or carbon treatment.
People in the Molalla area should not be concerned about exposure during the cleanup process, Hafley said, as all contaminated material would be managed carefully.
DEQ will make a final decision on the method after the public meeting on March 10 and after the public comment period closes on March 15. Hafley said a decision could take a month or two. Cleanup would begin in summer of 2020 or 2021, Hafley said, though Avison noted 2020 could be a tough timeline to pull off due to permitting guidelines.
"People ask, 'Well, why didn't you clean this up sooner?' Well, we've been trying," Avison said. "There's more and more research, and we have been doing work on it all along."
This recommended combination cleanup method is estimated to cost Avison $896,000, and cleanup on mill properties has already amounted to millions of dollars, Avison said.
"[The combination method] was not the cheapest, but it probably is the most protective," Avison said. "It's probably the one that can be done sooner…with minimal destruction of wetlands."
He added, "It's tough. We have some old insurance money, but it's never enough."
Avison is hopeful though that industrial development of the north parcel could offset some of the cleanup costs. He said he is working closely with Clackamas County on the potential development, and the county has a couple of ideas for use, such as secondary wood manufacturing or data centers.
"If we can get this land turned around and get some employment on this land, it's just great for everyone," Avison said. "Not putting some big, noisy industrial thing, but some employment opportunities there where people aren't commuting long distances. People in Molalla commute to Hillsboro; it's crazy, and if they can work in Molalla and not have to drive those long distances, it's just good for everyone."
He said, "We just want to get through the process and we're getting closer."
You count on us to stay informed and we depend on you to fund our efforts. Quality local journalism takes time and money. Please support us to protect the future of community journalism.