Mercury Pollution Minimization Plan (Mercury Green Tier Charter Program)
The Wisconsin Department of Natural Resources (WDNR) established a Mercury Green Tier Charter Program whereby municipalities could resolve to participate in this charter program to avert the inclusion of mercury limits into their wastewater discharge permits. In 2008, by resolution, the City of Marshfield committed to participate in this charter program and develop a Mercury Pollution Minimization Plan (PMP). In September 2008, this plan was initiated by contacting all known potential dischargers of mercury. They included dental facilities, medical facilities, schools, and industries. Some site visits were made and some contact letters were sent. Included were questionnaires with information that reported past eliminations of mercury discharges, current best management practices, mercury elimination equipment installations, and future mercury elimination or management plans. These assessments revealed that all dental facilities but one had installed amalgam separators. The one having no amalgam separator installed was given installation orders and they committed to the installation. All other potential mercury discharge sources had eliminated use of elemental mercury and disposed of all elemental mercury from their sites except one school. Elimination of elemental mercury use in that school is pending. This program will continue in the future through annual inspections of all dental facilities amalgam separators to assure that best management operational and maintenance practices are being performed. Records of the annual inspections will be kept on file at the Wastewater Utility office.