The Challenge
Spheros Environmental conducted toxicological evaluations of sediments, soils, and site waters as part of a Baseline Ecological Risk Assessment (BERA) for cleanup efforts under CERCLA at a former smelter site in Great Falls, Montana. The site served as an active copper refinery and smelter since 1891. Contaminants of concern at the site were multiple metals, including arsenic, mercury, copper, and antimony.
Our Solution
The Ecotoxicology Department at Spheros Environmental performed five bioassays with multiple chronic endpoints to determine potential impacts to soil, sediment, and water biota: a freshwater midge life cycle test, a freshwater amphipod survival reproduction and growth test, a water flea survival and reproduction test, an earthworm reproduction and bioaccumulation test, and a plant growth and development test.
Subcontractor
Results +What makes this unique
Thirty-three soil samples, five sediment samples, and five water samples underwent bioassay testing. Tests followed USEPA and ASTM guidance with site-specific adaptations to ensure relevance for the risk assessment. Several of the tests conducted are known to be challenging and laborious, with few labs able to perform them. Despite this, Spheros Environmental successfully met acceptability test criteria and was able to efficiently test all samples within the expiration hold times. Results were instrumental in determining if potential impacts to biota were present at the site and where those impacts may extend.
Project Experts
