Press Releases

June 20, 2011

dnr.wi.govWisconsin DNR News Release

ERCO Worldwide Completes Major Mercury Emission Reduction Project

News Release Published: June 20, 2011 by the Central Office


  • Bart Sponseller at the Department of Natural Resources (608) 266-1058;
  • Geoff Bertin at ERCO Worldwide (715) 887-4000

MADISON – The Wisconsin Department of Natural Resources and ERCO Worldwide are announcing the successful completion of a project that significantly benefits both the environment and Wisconsin’s economy.

ERCO Worldwide owns and operates a chlor-alkali plant in Port Edwards, Wisconsin. Until 2009, the plant used mercury cell technology to produce chlorine products and was responsible for about 20% of the annual mercury emissions reported in Wisconsin. In August 2007, ERCO’s parent company, Superior Plus, approved a capital investment to replace the mercury cell technology with mercury-free membrane cell technology.

The $135 million project eliminated process-based mercury emissions to the environment, expanded production capability, strengthened the business for the future and secured jobs in southern Wood County.

Natural Resources Secretary, Cathy Stepp said, “This is an excellent example of a ‘win-win’ for the environment and the economy. I commend ERCO for their efforts. Because of ERCO’s voluntary and forward looking investment, mercury emissions in our state are significantly reduced.”

DNR regulates mercury emissions under state rule NR446. It entered into a cooperative effort with the ERCO as part of the permitting process to observe the facility’s compliance and to assure the mercury cell demolition project was conducted in a manner that would not endanger human health or the environment. DNR was granted permission to conduct monitoring on ERCO’s property for mercury before, during and after the conversion project.

Geoff Bertin, Plant Manager, commented, “While the permitting process for our project was quite rigorous, we commend DNR for their cooperative effort in sharing ongoing mercury monitoring results and for obtaining the necessary permits in an timely fashion.” Results obtained during this project are contained in the report on the Department’s website []

Monitoring was conducted from 12/01/2008 through 03/31/2011, beginning about 6 months prior to the conversion project start, and ending about 11 months afterwards.

Average monthly mercury concentrations observed during monitoring decreased more than 10-fold during the project, while maximum monthly concentrations decreased by approximately 100-fold.

During the course of the project, the maximum monthly average concentration did not exceed 15% of the of the NR446 standard level. While during the final months of the project there remained some variability in the concentrations observed, monthly average concentrations are approaching the global background concentration for mercury observed in rural and remote sites.