Final chapter?

Koppers, the wood treatment plant whose operations fouled the soil and water in parts of south Oroville for nearly half a decade, closed in March of this year. And, although ceasing operations has helped clear the way for the federal Environmental Protection Agency to move forward with the Superfund site cleanup, the facility’s legacy—not to mention the soil- and water-cleansing equipment—will stick around for at least 10 more years.

Charles Berrey, the project manager for the EPA, says that dilution of the water contamination, caused by wastewater handling and wood treatment storage procedures, will take at least another decade before acceptable levels are reached. The plant was placed on the Superfund list in 1984.

The Koppers Co., Inc. site is in south Oroville a half-mile west of Highway 70 on Baggett Marysville Road. Wood treatment operations have taken place on the site since 1948, although Koppers Co. did not acquire it until 1951. In 1988, Beazer East, Inc. bought the site and later sold it to Koppers Industries, Inc., which carried the same name but was a different company than the original Koppers.

From 1962 to 1988, operations at the plant involved treating wood products with a chemical preservative containing dioxin, which is known to cause cancer and other severe health problems in animals and is considered a probable human carcinogen. In the early ‘80s Dioxin was discovered in large amounts in the site’s soil and water.

Originally, the EPA had planned to clean up the soil contamination using natural bacteria that would break down the toxic compounds. However, soil samples taken in 1992 indicated much higher levels of dioxin than anticipated—as high as 158 parts per billion. The recommended limit for worker exposure is 5-7 parts per billion.

Today, the contaminated water still on site is pumped out, treated and then re-injected into the underground aquifer. Berrey says that process should continue for, and very possibly much longer than, the next 10 years.

The soil, or at least 80 percent of it, has been removed from the 200-acre site and replaced. However, on four acres that sat under the processing area where creosote and other chemicals were injected into the wood, the soil and water have been deemed technically infeasible to clean and will have to be monitored indefinitely.

“Four acres of the 200 have an environmental problem that isn’t going to be cleaned up,” Berrey said.

If, sometime down the line, there are signs that the water is migrating away from that particular site, the water treatment will begin again, which means, of course, that the water-treatment equipment must also stay on site indefinitely.

“The cleanup is going well,” Berrey said. “But as you get down to the last parts, it gets harder. Think of it as a soaked sponge. When you first squeeze it you get 90 percent of the moisture out. That last 10 percent takes a number of squeezes.”

At this point, the cost of the cleanup stands at $39.5 million, Berrey said. Beazer East, Inc. retains the financial responsibility for the operation, despite having sold the company.

Since the late 1980s, some 38 residences south of the plant have been supplied with drinking water from the Oroville-Wyndott Irrigation District because the water from their wells was deemed too poisonous for human consumption. Today all but seven of those residences have been put back on their wells.

Many of these same neighbors have long been suspicious of the EPA and its cleanup efforts. There have been at least three fires at the plant, the most recent in 1996. In 1987, a fire erupted when a worker accidentally opened a valve to a 40,000-gallon butane tank, sparking an explosion and fire that burned 3,000 to 5,000 pounds of the chemical PCP, which in turn created the highly toxic dioxin, which was carried by the smoke.

At the time of the explosion, Warren Ambrose lived along Lone Tree Road, just south of the plant. He moved to another part of Oroville about six months ago.

“I remember that night,” he recalled recently. “We were just up the hill from Koppers. The explosion shook the ground.”

County health officials decided not to evacuate area residents even as plumes of smoke passed over and through the rural neighborhoods south of the plant. The next day, after residents complained of symptoms of chemical poisoning and some 36 hours after the fire, health officials ordered an evacuation.

A few days later, county and state health workers began medical tests for 350 neighbors. Neighbors were warned not to slaughter their livestock for human consumption until the animals were tested for contamination.

“They built some kind of transfer area over there that they were supposed to watch,” Ambrose said. “But I never saw anybody come out and check it.

“You’d go to these meetings that they would hold and you’d hear these fellows talk and you’d just have to take their word for it, that they were cleaning it up.”

Last year the state Department of Health Services sent a letter to “local veterinarians and ethnic grocery stores” warning residents of Oroville and nearby Palermo and Thermalito.

“This letter is for people who eat eggs or meat from chickens raised on soil in the greater Oroville area,” the letter said. “Since 1987, the California Department of Health Services (CDHS) has been investigating contamination by two types of chemicals (dioxins and furans) in several areas of California. Eggs from chickens raised in direct contact with the ground and soil from a number of homes in the greater Oroville area have been tested. Dioxins and furans were found.”

The letter goes on to say, "The level of these chemicals in Oroville eggs and soil have not gone down with time."