Monday, July 27, 2009

Mercury TMDL - MPCA Proposal To Control Hg Air Emissions

The Minnesota Pollution Control Agency (MPCA) is requesting comments on new air quality rules involving mercury air emissions reporting. The Rules are being drafted in accordance with a statewide mercury TMDL, which aims to reduce mercury in fish.

The impeding rulemaking falls into two general categories:

1) Mercury Emissions Reporting, and
2) Plans for Mercury Emissions Reductions at Certain Facilities

Rulemaking will require certain facilities holding an MPCA air emissions permit to develop their own Mercury Emissions Reducing Plan for incorporation into their State air emissions permit. Some facilities will also be expected to develop reduction plans to meet sector or source reduction targets and timeframes listed in the “Strategy Framework for the Implementation of Minnesota’s Statewide TMDL”, which outlines the State's strategy to address the many lakes & rivers in the State impaired due to high concentrations of mercury in fish.

The proposed new and amended rules will also establish the emission calculation methods for facilities to track their mercury emissions and submit an annual mercury emissions report to the MPCA. Although MPCA is considering having mercury emissions reporting take place concurrent with the annual air emissions inventory process, the proposed rulemaking does not include any major changes to the criteria pollutant emissions inventory.

The proposed rule will also establish the minimum requirements for Mercury Emissions Reduction Plans from each facility to address how they will reduce mercury emissions. The Plans will either be incorporated into their air emissions permit as enforceable requirements or will be made enforceable using other means available to the MPCA. Reduction targets are established for taconite processing facilities, utility boilers, commercial, institutional and industrial boilers, petroleum refineries, secondary metal smelters, sewage sludge incinerators.

As a separate element of the Statewide TMDL, MPCA is also proposing evaluations for mercury sources as a requirement under its Multi-sector Industrial Stormwater General permit. Facilities that identify mercury sources will need to develop a Mercury Minimization Plan relative to stormwater discharges.

Caltha LLP provides expert consulting services to public and private sector clients nationwide to address water quality standards, wastewater permitting and assessing potential impacts of chemicals in the aquatic environment.

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