BOSTON, Ma. — On October 9, 2009, Geosyntec client Omya North America held a ribbon-cutting ceremony to mark the opening of a new $10-million tailings dewatering facility (TDF) at its ground calcium carbonate plant in Florence, Vt. Geosyntec is Omya's groundwater consultant, and through a two-year state-mandated, Omya-funded study, has helped them establish unprecedented credibility with regulators and various stakeholders.
Quarried marble is brought to the Vermont facility where it is crushed, milled, and purified to produce finely ground calcium carbonate used in paper, paint, plastic, food and pharmaceuticals. Flotation technology is used to separate non-calcium carbonate minerals from the final product, producing tailings. Prior to the construction of the TDF, Omya's tailings were slurried to on-site settling cells and periodically transferred to on-site former quarries for storage.
Omya constructed the TDF to dewater the plant's tailings prior to storing them in new on-site lined storage cells currently under construction. This major change in operations will keep the tailings leachate and, in particular, a chemical known as aminoethyl-ethanolamine (AEEA, a flotation agent impurity), from coming in contact with site groundwater and surface water. In addition, the TDF will provide a consistent dewatered tailings material, facilitating potential reuse as a marketable product.
Vermont Governor James Douglas, Omya North America president Tony Colak, other Omya senior management, and a range of community leaders attended the ribbon-cutting. Gov. Douglas praised Omya for taking steps to eliminate sources of groundwater contamination in Vermont and for pursuing sustainable end uses for their tailings.
Geosyntec project manager David Adilman, PG, said, "Omya should be commended for their extraordinary efforts improving process operations to reduce environmental impacts."
Omya is the world's largest calcium carbonate supplier with ten production plants in North America and over 100 plants located in more than 50 countries worldwide.
Geosyntec, founded in 1983, provides consulting engineering and science services throughout the United States and internationally. With more than 45 offices in the U.S. and select international locations, Geosyntec engineers and scientists are known for their technology leadership and practice innovation in the areas of geotechnical and geoenvironmental engineering, contaminated site assessment and remediation, groundwater assessment and remediation, risk assessment and toxicology, urban stormwater management, water and natural resources management, solid waste disposal facility permitting and design, and environmental biotechnology.