Mercury Sources to Water and Associated Impacts Chris Piehler

Rainfall LPDES Permitted facilities –46 facilities with Hg parameter limits on wastewater discharges –104 facilities with Hg parameter reporting requirements on sludge –Primarily POTWs, some fertilizer, some industrial and others (based on PCS) Other sources –Categorical Industrial Users –Minor facilities yet to be included in PCS –Permitted dischargers that should have Hg limits –Unknown, un-permitted sources Mercury Sources to Waterways

Ambient Water Quality Monitoring Network – clean metals analyses Water/Sediment/Fish Tissue sampling within the Mercury program Sediment surveys Monitoring Mercury in Ambient Waters

= Methylmercury Methylmercury Formation Occurs in Sediments

= Methylmercury Bioaccumulation

Natural Conditions –Redox Potential –Organic content –Grain size –Sulfate/Disulfovibrio –Mercury!!! –Salinity –pH/Alkalinity Methylation

Water Quality Assessments: the biannual 305b Report Impaired waters make up the 303d list Water bodies with fish advisories are considered “impaired” even though water standards not exceeded Impaired waters are candidates for TMDLs Impaired Waters

Total Maximum Daily Loading 99.5% of mercury loading to some central Louisiana streams/lakes from atmospheric deposition (EPA6, 2002) Massachusetts petitioning Region 1 EPA to consider air emissions reduction in mercury TMDLs Florida publishes report on integrating atmospheric deposition with aquatic cycling – near source reductions resulted in fish tissue concentration reductions (November 2003) Potential Effect of TMDLs

For more information regarding mercury in Louisiana water and fish please contact: Chris Piehler (225)