James Ranville Colorado School of Mines Department of Chemistry - PowerPoint PPT Presentation

Ch Chemical l and d Bi Biological l Re Responses s in n the e North h Fork k of of C Clea ear C Creek F eek Fol ollowing g Re Remediation n of f Acid d Mine e Dr Drainage e Inputs s James Ranville Colorado School of Mines Department of Chemistry NIEHS Superfund Research Program (SRP) Progress in Research Webinar May 13 th , 2019

Acknowledgements Co-PIs & Students Colorado School of Mines Investigating Biogeochemical Controls J. Ranville, J. Meyer, E. Lloyd, J on Metal Mixture Toxicity Using Murphy Stable Isotopes and Gene Expression Colorado State University W. Clements & Chris Kotalik University of Florida C. Vulpe and Dani Cucchiara • Grant 5RO1 1ES024358

Overall Study Objectives/Approaches We wish to better understand how metal mixtures affect aquatic toxicology and metal bioavailability and how the presence of metal mixtures influence the remediation effectiveness for mining impacted waters We are using a laboratory and field based-approach. Laboratory studies of mixture toxicity utilize D. magna , with mortality, metal uptake (measured and computed by BLM), and gene expression as endpoints. Bioavailability of metals from sediments utilize 65 Cu isotope labeling with snails as the test organism. We are directly measuring the biological and chemical responses to remediation of the mining effluents (todays presentation).

Talk Outline • Background • Site Description/hydrology • Water Chemistry Response • Biological Recovery • Outreach • Summary

Black Hawk, CO 1987 Introduction • North Fork of Clear Creek (NFCC) located 50 km west of Denver, Colorado USA • Mining activity 1850s – 1950s • Acid mine drainage (AMD) and mining solid wastes (sulfide weathering) • Mixtures of toxic metals (Cu, Zn) enter stream effecting water column and sediment chemistry • Stream life highly impacted (absent)

Armoring Aquatic Welcome to the Life ? North Fork Clear Creek-2016 Flocculant bed and suspended sediments Dissolved metals

Treatment Plant • High Density Sludge • Operational March 2017 • Capture and treatment of two point sources of AMD entering stream • Gregory Incline and National Tunnel • Initial cost of $19.66 million Photo Credit: Heather Henry

Flow Gauge Flow

Research Goals (Chemistry) • Monitor water chemistry and biology pre- and post-remediation • Understand effectiveness of treatment plant in decreasing total metal loading in stream • Understand geochemistry of changes in water chemistry (dissolved) since implementation of remediation • Evaluate potential aquatic toxicity of dissolved metals

Discharge Scouring Base Flow Scouring Base Flow 2500 Sampling Dates 2000 Discharge (L/sec) 2017 2018 2018 2019 1500 1000 500 0 7 8 7 7 7 7 8 8 8 8 8 9 9 1 1 1 1 1 1 1 1 1 1 1 1 1 - - - - - - - - - - - - - r y v r y v r l p n l p n u u a a a o o a e a a e a J J M M M M M N J N J S S

Visual Improvement in Stream Appearance March- October 2017 @ Downstream Site March 23 May 1 May 16 August 29 October 27 March 28: treatment of one source September 15: 24/7 begins, periodic shutdowns occur, treatment begins second source treatment begins in July

Decrease in Total Metal Loading Decrease by factor of 50 Decrease by factor of 150 Decrease by factor of 1600 Zinc Copper Iron Spring Scouring Event 1000 1000 1000 Pre- Treatment Post-Treatment 100 100 100 10 10 10 Load (Kg/day) 1 1 1 Pre- Treatment Post-Treatment 0.1 0.1 0.1 Pre- Post-Treatment Treatment 0.01 0.01 0.01 Aug-16 Mar-17 Sep-17 Apr-18 Oct-18 May-19 May-19 May-19 Aug-16 Mar-17 Sep-17 Apr-18 Oct-18 Aug-16 Mar-17 Sep-17 Apr-18 Oct-18

Multiple Remaining Sources Flow TP with Differing Metal Compositions REF 1 REF 2 ANT RAP 100 Cu Zn Percent Increase Between Sites 80 60 40 20 BDL 0 REF 1 to REF 2 REF 2 to ANT ANT to RAP

Multiple Remaining Sources Flow with Differing Metal TP Compositions ARG REF 1 REF 2 ANT RAP RBP USGS

Total Iron Concentration: Near Complete Removal 25 Pre-Treatment Post-Treatment Matchs Visual Improvement 20 Total Iron (mg/L) 15 10 5 0 Aug-16 Nov-16 Mar-17 Jun-17 Sep-17 Dec-17 Apr-18 Jul-18 Oct-18 Feb-19 May-19

Only Partial Lowering of Dissolved Copper 45 Pre-Treatment Post-Treatment 40 Dissolved Copper (ug/L) 35 30 25 20 15 10 5 0 Aug-16 Nov-16 Mar-17 Jun-17 Sep-17 Dec-17 Apr-18 Oct-18 Feb-19 May-19 Jul-18

Particulate Iron is Your Friend For Copper 100 90 80 Percent Dissolved Copper 70 60 50 40 Pre-remediation 30 20 10 Stumm 1992 0 0.01 0.1 1 10 100 Particulate Iron (mg/L)

Predicted Toxicity of Instream Cu + Zn to Daphnia magna • Based on measured dissolved Cu and Zn in stream • Cu and Zn EC50s taken from previous 48-h lethality tests with D. magna neonates (EC50 = 50% mortality conc.) • Toxic units • TU Cu = [Cu]/EC50 Cu • TU Zn = [Zn]/EC50 Zn • ΣTU = TU Cu + TU Zn • Predicted mortality = f(ΣTU)

Predicted Toxicity of Instream Dissolved Copper and Zinc (considering effects of multiple metals) Dilution Base Flow Dilution Base Flow 100 80 Mortality (%) 60 40 20 0 7 7 7 7 7 7 7 7 8 8 8 8 8 8 8 8 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 - - - - - - - - - - - - - - - - t t r r y n g p v n r y l g p v u a a c p c o o a u u a a u e e O J O M M A M A N J M A N J S S

Chemistry Conclusions • Total Copper, Iron, and Zinc loads have decreased to different degrees since treatment began • Multiple and variable sources of uncaptured metals continue to enter NFCC in variable ratios • Particulate Iron is your friend for Copper but not Zinc • Predicted toxicity of Zinc and Copper to Daphnia magna remains elevated post remediation • Cannot treat what we do not capture

Field Biomonitoring Hypotheses for AMD Remediation • H(1): Algal biomass will increase • H(2): Benthic macroinvertebrates will increase in abundance and taxa richness • H(3): Benthic and emerging adult biomass will increase • But how quickly?

CSM/CSU Study Objectives Treatment Plant Measure chemical and biological • stream parameters Identify chemical and biological • processes that drive post- remediation stream conditions Determine remediation • ”Impact” Sites Flow direction effectiveness for stream ecological health Sampling Locations ”Recovery” Sites Golden 30 km

North Fork Clear Creek, Colorado Algal Colonization

North Fork Clear Creek, Colorado Larval Colonization

North Fork Clear Creek, Colorado Benthic vs Emergence Biomass

Field Biomonitoring Results and Conclusions to date-- • Discrepancies in algal colonization at AMD remediation sites, likely due to top-down control by grazer aquatic insects • Increased abundance and taxa richness at downstream sites, but richness is still far below Reference site observations • Benthic and adult emergence biomass improved at downstream sites from Year 1 to Year 2. This suggests increased benthic production and increased subsidy export to terrestrial environments following remediation

Outreach to Local STEM K-12 Schools CSM Summer programs engineering Treatment Impacts on Aquatic Life Sources

CSM Environmental Chemistry Field Session Site investigations for local stakeholders

Questions