Environmental Protection Agency and Montana Department of Environmental Quality crews will begin drilling water wells in Somers to determine whether a plume of contaminated groundwater has moved underneath the former Burlington Northern tie treatment plant. An EPA report suggests that it may have, but DEQ Project Officer Lisa DeWitt said more testing is needed before the agencies can be certain.
The contaminated groundwater poses little threat to the public because the town of Somers uses city drinking water, according to state and local officials. However, it appears the plume of contamination has expanded underneath a handful of houses and the EPA will conduct air tests inside those homes to determine if any contaminated vapor has escaped inside.
“Based on previous indoor air samples we have done, we don’t believe there is any immediate health risk to the public,” DeWitt said. “But we just want to do some follow-up tests.”
The 80-acre site near downtown Somers was once home to a railroad tie treatment plant, owned by the Great Northern Railway and established in 1908 and operated until 1986. Today, the land is owned by Great Northern successor BNSF Railway. For nearly a century, the plant produced wooden railroad ties that were coated with creosote to protect the ties from changing weather. Other chemicals used in the tie-making process included zinc chloride and petroleum preservative mixtures. After a tie was coated with protective chemicals it was allowed to dry out on a “drip track.” According to an EPA report, the process produced up to 1,000 pounds of sludge every two years that impacted both the soil and groundwater. The contamination was discovered in 1984 and later that year the area was designated an EPA Superfund site.
In the years since that designation, the soil at the site has been cleaned and attempts have been made to treat the groundwater. But the water treatment process is challenging in that area because of how compact the soils are, DeWitt said. The groundwater moves at an incredibly slow pace and in 2007 the treatment system was shut off by BNSF, with the approval of the EPA and DEQ. DeWitt said since then, the plume of contamination has been monitored and the government agencies reserve the right to turn the system back on.
Since the early 1990s, the EPA has conducted four separate reviews of the cleanup progress and the most recent report, issued in February of this year, suggested the plume of contaminated groundwater may have moved outside of the Superfund site and underneath nearby homes. DeWitt said since there is no data from every point in the surrounding area, it is hard to know when the contaminated water moved. The agency hopes to determine that by drilling test wells this summer.
“We want to get a better and more complete view of the exact contamination,” DeWitt said. “The additional studies will help give us a better picture of where (the water) is at.”
The water poses little threat to the public as long as it is not consumed and does not come in contact with surface water. Much of the site is designated as a controlled groundwater use area, according to Flathead County Health Officer Joe Russell, which means no one can drill a well there. He said if the contaminated groundwater plume has moved, the county would likely request that the Montana Department of Natural Resources and Conservation expand the well restrictions.
“In a perfect world, we’d take every bit of contaminated water out of the ground, but it’s just not realistic,” Russell said.
DeWitt said officials will know more once the water is tested. She also said a town meeting will likely be held in September to address public concerns.