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Mine sampling provides no answers - yet

by Brad Fuqua Western News
| August 15, 2008 12:00 AM

While early sample testing for asbestos in and around W.R. Grace's former vermiculite mine yielded interesting results, Environmental Protection Agency officials aren't sure what the data all really means just yet.

Nearly 50 people listened, absorbed and asked questions during an EPA meeting Tuesday night in Libby. And the underlying theme for the evening was that officials need time to assess sampling results.

“We sure have to do a lot more work to see what this all means,” said Bonnie Lavelle, remedial project manager with EPA's Superfund Region 8. “It's tough working up there at the mine and getting asbestos data back from the laboratories. It's going to take a while … it's going to be a big project.”

So big, in fact, that the vermiculite mine testing is expected to go on for years.

Despite the overwhelming tasks ahead, those in attendance showed great interest in the early testing. In a project that started nearly one year ago, sampling activities took place at various sites around the mine over a four-week period this past October.

EPA officials established a boundary for its initial activities including Rainy Creek, Fleetwood Creek, Carney Creek, the Kootenai River, Rainy Creek Road and surrounding forest and ponds. Surface water, sediment, mine waste, soil, tree bark and ambient air were tested.

The concentration of asbestos covered the spectrum from high to low and in many areas, non-existent. But at this point, the results are simply numbers with questionable meaning.

“The highest concentrations, we're not sure what those mean, whether there is a problem or not,” Lavelle said. “It's just comparing concentrations.”

In what appeared to be good news, Lavelle reported no asbestos detected in any ambient air samples. However, the testing was limited with a program that ran over four weeks with four samples from each monitoring location. Those sites were established in a circular manner from the mine with more monitors in a downwind direction.

As one audience member brought up, last October was really wet. Air testing continues.

“This year, we started another program running over the summer,” Lavelle said. “Now we have a network of monitors closer to the mine. Folks are going up every week, checking pumps and collecting the filters.”

Surface water testing show the highest levels of asbestos in the tailings pond as well as a pond on Fleetwood Creek. High levels were also found in seeps and springs along Carney Creek. Lavelle said the Fleetwood Creek pond tests showed 125 million fibers per liter of surface water. The tailings pond site revealed 114 million fibers per liter.

Testing showed no asbestos in the northernmost site on Rainy Creek or where that creek flows into the Kootenai River.

Surface water testing started again in March and will continue through October, Lavelle said.

Sediment samples showed some level of asbestos in 22 of 24 testing sites. The highest levels were seen in the Carney Creek seeps and springs. Less than 1 percent was measured at the Rainy Creek-Kootenai River site.

“We don't know what these levels mean … it will take several more years to figure that out,” she said. “We've got a lot of work to do but we wanted to present what we have so far.”

Sediment sampling was performed in a “grab” manner with no depth testing done.

No sampling was done in the Kootenai River last fall but those efforts are part of this year's activities, Lavelle said.

During a Q-and-A session after the water and sediment discussion, a few audience members expressed a lack of confidence in sampling procedures. Lavelle followed up by saying that more results will come in from further testing to increase their knowledge.

The mine waste sampling results showed the highest concentrations of asbestos in rock outcroppings at the mine site. This portion of testing covered several categories. Nickel and chromium were also detected.

The most puzzling sample results revolved around soil and tree bark. Soil testing showed results that are positive on the surface.

“It looks to us something you would predict from wind direction and speed,” Lavelle said. “In soil, there are elevated concentrations in downwind direction 1 1/2 to 2 miles from center.”

Tree bark testing was done on Douglas firs that were at least 8 inches in diameter. Sample sections were two inches in diameter four feet from the ground and taken from the side of the tree facing the mine. The 8-inch diameter prerequisite guaranteed that the tree was there when the mine was in operation.

“Tree bark has us scratching our heads,” she said. “We're picking up asbestos in tree bark in all directions. We don't know what these levels mean … but you can see how we're scratching our heads given our soil results.”

Lavelle said the asbestos presence in the tree bark could represent historical impact. A big question is whether or not there is risk of contamination if the tree is disturbed.

“We were hopeful that it could give us information to draw a boundary but we can't say with confidence a limit of impact,” she said. “What we want to know is if it's released into the air if tree bark is disturbed.”

There are currently no logging activities going on in the area. More testing is on the horizon to determine risk.

“Our plan is to do this methodically. Next year, we'll have an activity-based sampling program,” Lavelle said. “Logging, hiking, whatever else people do that could get them exposed. … We'll collect samples of air when those activities are going on and then we'll have something to evaluate. Right now, the answer is we don't know.”

Organic material from the bottom of the trees was also tested but no results are available from the lab. Lavelle did say, however, that preliminary information reveals some level of asbestos.

The second phase of sampling features three segments - surface water and sediment, air and groundwater, and fish.

The topic of measuring impacts on fish and wildlife drew the interest of some of those in attendance. Although a partial explanation of expected measurement procedures was given, officials said it was very early in that process.

The sampling project is a joint effort between the EPA, Montana Department of Environmental Quality and W.R. Grace. Each has its own role with Grace performing sampling and the EPA assessing the data. Labs used to analyze samples are EPA contractors and not those of Grace.

Lavelle stressed to audience members that the EPA is always available to answer questions on any concerns revolving around the oversight plan.

The bottom line was that testing will continue for some time.

“We've got a couple more years of work to do with sampling and assessing risk … if it looks unacceptable and developing alternatives on what to do with that,” Lavelle said.