The Clearwater BioLogic sulfate remediation system was developed and tested in northern Minnesota, where a century of iron and taconite mining has left excess sulfate in abandoned mine-pit lakes. In the mid-1960s, area lakes and rivers were found to contain rising sulfate levels, and at times acidic runoff and dissolved metals. These substances were harming ecosystems, including the wild rice that grows in some of those waters. In 1973, Minnesota established a strict sulfate standard (10 milligrams per liter) to protect wild rice, but it was rarely enforced for lack of a cost-effective remediation method. Over time, reverse osmosis systems were developed to remediate sulfate, but they were deemed prohibitively expensive by the mining companies.

The idea for a new, affordable, nature-based sulfate remediation system came from environmental engineer Jeffrey Hanson, an Iron Range native, who, with Bill Newman of RNAS Remediation Products Inc., formed Clearwater BioLogic, LLC, to install and operate sulfate reduction systems based on this combined technology.

The process is now in the testing phase on-site at a mining location and a grant by the White Iron Chain of Lakes (WICOLA) is soon to be ratified by the Minnesota legislature and its process to begin in July 2026. Read more about our onsite testing trailer.