Libby Groundwater Superfund Site Agencies working toward permanent control plan
A plan to put water-use restrictions and monitoring wells on the Libby Groundwater Superfund Site is working its way through the review process.
The U.S. Environmental Protection Agency and International Paper met with the Lincoln City-County Board of Health last month to explain the technical approach in developing a permanent controlled groundwater area boundary for the Superfund site that dates back to 1983 and includes the former Champion mill site.
“A controlled groundwater area is needed to protect human health by preventing installation and use of groundwater wells for drinking water or irrigation and other commercial uses in a specifically defined area,” explained Jennifer Harrison, a public-affairs specialist with EPA.
The boundary also is needed to prevent private or commercial groundwater wells from increasing the size of the current contaminated plume by changing current flow conditions in the aquifer, Harrison said. Pumping could induce movement of the contaminant plumes in the groundwater.
Historic wood-treating operations on the property polluted soil and groundwater with pentachlorophenol (PCP) and polynuclear aromatic hydrocarbons (PAHs).
The proposed boundary for the controlled groundwater area encompasses 1,123 acres and includes existing plumes, a buffer zone to address the effects of pumping on plumes, historic landfills and current soil treatment units.
The permanent controlled groundwater area designation is based on meeting three of five criteria: groundwater within the boundary is not suited for beneficial use; projected groundwater withdrawals from the aquifers would induce or alter contaminant migration exceeding water-quality standards; and public health, safety or welfare will be at risk.
Although the proposed plan addresses the controls as permanent, Harrison said the EPA is working on renewed remedial activities to address cleanup of the plume over time.
“If the plume is remediated and shrinks to the extent that the CGA (controlled groundwater area) or parts of the CGA are not needed, we can work with community groups to petition for removal or alternation of the CGA,” Harrison said.
Regarding any future development in the boundary area, the EPA is not aware of any businesses or residences without a water supply. Most of the boundary area is serviced by city water.
“If we discover any properties that are not serviced by city water and are within the final CGA boundary, we will ensure that those properties have access to water that is not impacted by site contaminants,” Harrison said.
The Lincoln County City-County Board of Health was asked earlier this year to consider being the petitioner for the creation of a permanent controlled groundwater area. George Jamison, Board of Health vice chairman and chair of the recently created Institutional Controls Steering Committee for both the groundwater and asbestos Superfund sites, addressed preliminary concerns in a letter following the Nov. 7 meeting with the EPA and International Paper.
Jamison said that while his concerns are personal comments, “they do represent a summary of concerns that will be reported to the Board of Health.”
One of his concerns is the elimination of groundwater use within the boundary area, given that the CGA is a more permanent and final action.
“The Board of Health will be sensitive to questions related to the consequences of loss of the resource, especially related to water-supply issues for the Port Authority and city of Libby,” Jamison wrote in his response.
Another concern is the county’s enforcement responsibilities. While the Board of Health recognizes the need for effective monitoring of compliance and enforcement, Jamison said he wants to be assured the county has the resources to meet its obligations.
The Libby Groundwater Site has two operable units, the first for the alternate water supply for the city of Libby, and a second for the cleanup of the contaminated soil and groundwater.
There is some geographic overlap between the Libby asbestos and groundwater Superfund sites, Harrison said, but she added that the sites are addressing different contamination in different ways.
Harrison noted the controlled groundwater area approach has not been finalized and is subject to change pending further input from the Board of Health, the Lincoln County Port Authority and the Montana Department of Natural Resources and Conservation.
The DNRC has up to 330 days to review the proposal, and will schedule a public hearing at some point. After considering any public comment, the DNRC will make a formal decision regarding the controlled groundwater area.
Harrison said the EPA also is expecting input from the Lincoln County Port Authority.
Features editor Lynnette Hintze may be reached at 758-4421 or lhintze@dailyinterlake.com.