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Investigation Confirms Contaminated Groundwater, Cyanide at CFAC

first_imgFor decades, business boomed as the Anaconda Aluminum Company plant in Columbia Falls produced about 1 million pounds of aluminum per day while an inconspicuous and hazardous side effect perpetuated in plain sight.The process of extracting aluminum metal, a lucrative yet messy practice rooted in the dawn of the Industrial Revolution, ended up creating massive amounts of waste material known as spent potlining. These hazardous byproducts contained an abundance of harmful elements, including highly poisonous cyanide, as well as fluoride, arsenic and corrosive metals and oxides.Before the dangers of spent potlining were discovered and the material was declared hazardous waste by the U.S. Environmental Protection Agency in 1988, significant amounts were discarded at landfills throughout the 960-acre industrial site near the Flathead River.Now, in the early stages of investigating the newly designated federal Superfund site on the outskirts of town, the ramifications are surfacing.No significant red flags have emerged so far, according to EPA officials, but the first round of sampling confirmed the existence of cyanide, fluoride and hazardous metals to varying degrees at the property.According to the Columbia Falls Aluminum Company, the property owner that is conducting the investigation with oversight by the EPA and Montana Department of Environmental Quality, the investigation confirms groundwater has been impacted by materials placed in the legacy landfills that were used from 1955 until approximately 1980. The studies indicate the material is not moving toward drinking water wells in the nearby residential neighborhood known as Aluminum City, according to CFAC officials.“With the information I have seen, there were no new surprises,” Mike Cirian, EPA’s remedial project manager, told the Beacon.“We are in the process of reviewing the report … Upon completion of our review we will use this information to help guide any changes necessary on the next phase of sampling.”EPA officials will meet with the Columbia Falls City Council on April 17 and join a public meeting tentatively scheduled for April 19. The location remains to be determined and will be announced soon.»»» Click here to read the CFAC site investigation reportThe 7,300-page report detailing the first round of remedial investigation outlines the results from more than 700 samples that were collected from the site’s soil, groundwater, surface water and sediment. A total of 44 monitoring wells were installed and the first phase of site investigation took place over a seven-month span in 2016. A second round of testing is underway now and results should be published by June, according to a CFAC official.One of the primary sources of hazardous materials is the legacy landfill on the northwest end of the property. The landfill has been isolated but a water plume has developed.“The preliminary indicators are that there are no red flags and no surprises,” John Stroiazzo, CFAC project manager, told the Beacon.“The source is where we thought it was and this data now confirms it. We know where that water plume is going and the program continues with additional monitoring.”Cyanide was found to be widespread across the property. It was detected within 93 percent of surface samples, 87 percent of shallow samples, 56 percent of intermediate samples, and 66 percent of the below water table samples, according to the report.The report notes that cyanide concentrations were below the EPA’s residential regional screening level of 15 mg/kg in all samples with the exception of four samples collected from the northeast percolation pond (one surface, two shallow, and one intermediate).Cyanide concentrations were below the EPA’s industrial regional screening level of 2.3 mg/kg in all samples with the exception of eight samples collected within the northeast and northwest percolation pond and two samples beneath the former cathode soaking pit location within the main plant area.Regional screening levels are site-specific standards that help inform EPA Superfund cleanup and risk assessment.Aluminum, arsenic, cobalt, iron, and manganese were detected at concentrations exceeding EPA regional screening levels of in more than 70 percent of all samples collected. Metals were detected frequently across the site with 16 different types found at frequencies between 90 and 100 percent of the samples collected. This is indicative of metals that are naturally occurring substances in the environment, according to the CFAC report.Fluoride was detected in 100 percent of surface and shallow samples, 98 percent of intermediate samples, and 100 percent of the below water table samples, the report showed. None of the fluoride concentrations exceeded the EPA’s industrial regional screening level of 4,700 mg/kg.The next steps of the multi-year remedial investigation will include preparing a Human Health and Ecological Risk Assessment Work Plan.“We successfully accomplished the goal of Phase I, which is critical to the project,” Stroiazzo said. “The work performed provides an understanding of site conditions and will help determine the roadmap forward.”He added, “We know moving this work forward is important to everyone involved in this project, including the community of Columbia Falls.”A copy of the report is available online and in the Columbia Falls Library. Email Stay Connected with the Daily Roundup. Sign up for our newsletter and get the best of the Beacon delivered every day to your inbox.last_img read more