RESEARCH ON MERCURY IN MINNESOTA RIVERS BRUCE MONSON

RESEARCH ON MERCURY IN MINNESOTA RIVERS BRUCE MONSON ENVIRONMENTAL ANALYSIS & OUTCOMES DIVISION

IDENTIFYING CAUSES OF HIGH MERCURY IN FISH • A THREE-YEAR PROJECT (2015 – 2017) RESEARCHING ECOSYSTEM PROCESSES THAT CONTROL MERCURY ACCUMULATION IN FISH • THE GOAL IS TO ACHIEVE SUFFICIENT KNOWLEDGE ABOUT THE CONTROLS TO INFORM ADDITIONAL EFFORTS TO REDUCE MERCURY IN FISH

IDENTIFYING CAUSES OF HIGH MERCURY IN FISH: ACTIVITIES • MOBILIZATION OF MERCURY AND METHYLMERCURY (2 YEARS) • METHYLMERCURY PRODUCTION AND DESTRUCTION • FOOD WEB AND FISH LIFE HISTORIES • GIS DATABASE AND CONCEPTUAL FRAMEWORK Project work plan, on the LCCMR’s web site: http: //www. lccmr. leg. mn/projects/2014 index. html#201403 j.

LOAD MONITORING (MOBILIZATION) • RIVERS: ROSEAU, THIEF, WILD RICE, MUSTINKA (2015 -2016); VERMILION & KETTLE (2016) • ALL SITES HAVE FLOW GAGES MAINTAINED BY USGS OR DNR • ROSEAU AND WILD RICE HAVE ONE STATION; OTHERS HAVE TWO • SAMPLE COLLECTION BEGAN AFTER ICE-OUT AND CONTINUED THROUGH OCTOBER • GOAL IS 25 SAMPLE EVENTS PER YEAR FOR TWO YEARS • USE FLUX 32 PROGRAM TO CALCULATE LOADS (KG/YR)

MPCA POLLUTANT LOAD MONITORING STANDARD ANALYTES • TEMPERATURE • DISSOLVED OXYGEN MERCURY ANALYTES • TOTAL MERCURY • SPECIFIC CONDUCTIVITY • METHYLMERCURY • TRANSPARENCY – SECCHI TUBE • TOTAL ORGANIC CARBON • PH • SULFATE • NITRATE-NITRITE • IRON – DISSOLVED • TOTAL KJELDAHL • TOTAL PHOSPHORUS • ORTHOPHOSPHATE-P • TOTAL SUSPENDED SOLIDS • TOTAL VOLATILE SOLIDS • TURBIDITY • UV 254 (QUALITY OF ORG C)

METHYLATION, WATER, & SEDIMENT STUDIES • RESEARCHERS FROM UNIVERSITY OF MINNESOTA-DULUTH, GUSTAVUS ADOLPHUS, & UNIVERSITY OF TORONTO • BEGAN JUNE 2015 IN ROSEAU, THIEF, & MUSTINKA RIVERS, CONTINUED IN 2016 • BEGAN SPRING 2016 IN VERMILION & KETTLE RIVERS • GROUNDWATER PIEZOMETERS ADJACENT TO STREAM BANKS AT TWO SITES IN EACH WATERSHED; WATER LEVEL SENSORS FOR CONTINUOUS MONITORING • TWO SITE COLLECTIONS OF SURFACE WATER, GROUNDWATER, SOIL, SEDIMENT, & POREWATER • MEASURED METHYLATION AND DEMETHYLATION RATES

BIOTA COLLECTION • RESEARCHERS FROM UNIVERSITY OF WISCONSIN – LA CROSSE • COLLECT WATER, SESTON, PERIPHYTON, BENTHIC MACROINVERTEBRATES, AND SMALL (PREY) FISH • MULTIPLE SITES IN EACH RIVER – SAME SCHEDULE AS OTHER COLLECTION WITH ADDITION OF ST. LOUIS RIVER IN 2016 • HUNDREDS OF BIOTA SAMPLES COLLECTED (AND FREEZE-DRIED) FROM 33 SITES IN THE SIX WATERSHEDS • UW-LACROSSE WILL ANALYZE SAMPLES FOR HG AND MEHG; SUBSAMPLES WILL BE SENT TO UMISOTOPE LAB FOR CARBON AND NITROGEN ISOTOPES • SPORT FISH COLLECTED BY MDNR & MPCA

Roseau Thief 2000 discharge (cfs) 2000 1500 1000 500 0 2. 25. 2015 4. 16. 2015 6. 5. 2015 7. 25. 2015 9. 13. 2015 11. 2. 2015 roseau-sub thief-major Wild Rice 600 1200 500 1000 discharge (cfs) Mustinka 400 300 200 100 0 2. 25. 2015 4. 16. 2015 6. 5. 2015 7. 25. 2015 9. 13. 2015 11. 2. 2015 mustinka-major mustinka-sub thief-sub 800 600 400 200 0 2. 25. 2015 4. 16. 2015 6. 5. 2015 7. 25. 2015 9. 13. 2015 11. 2. 2015 wildrice-major

WHAT ELSE ARE WE DOING? TRACKING FISH-MERCURY LEVELS

ANNUAL NUMBER OF WATERWAYS SAMPLED FOR FISH MERCURY CONTAMINATION: 2010 2015 Number of Lakes and Rivers 160 2010 -2011 Goal: 90 140 120 100 32 83 46 33 49 32 2012 -2013 Goal: 105 2014 Goal: 110 2015 Goal: 100 80 60 40 112 69 78 2010 2011 94 99 88 Newly Sampled Waters Re-sampled Impaired Waters 20 0 2012 2013 2014 2015 Annual Goal: Re-sample 10% of Hg-impaired waters; in 2015 revised to 100 waters per year Number of waters sampled in 2011 was lower than anticipated, due to the state gov’t shutdown Analyzing and reporting long term trends as part of strategic review

FISH COLLECTED FOR MERCURY AND PCBS AS PART OF MPCA’S INTENSIVE WATERSHED MONITORING PROGRAM • FISH COLLECTED AT “POUR POINT” OF MAJOR WATERSHEDS • GOAL: 5 GAME (PREDATOR) FISH AND 5 ROUGH (BOTTOMFEEDER) FISH • MERCURY ANALYSIS IN ALL INDIVIDUAL FISH • PCBS IN TWO LARGEST INDIVIDUALS OF EACH SPECIES • 10 YEAR CYCLE FOR WATERSHEDS; 5 YEAR CYCLE FOR MAJOR RIVERS

Installing wells at the Roseau River