Metals in the Benthic Macroinvertebrates in Coal Creek, Crested Butte, CO Scarlett E. Graham July 10, 2006 University of Colorado at Boulder Environmental Engineering REU Summer Student

Overview Motivation Background Hypotheses Methods Results Conclusions

Motivations Coal Creek Watershed Coalition Standard Mine is an EPA Superfund Site Coal Creek is a drinking water supply Recreation is a major contributor to the economy

Acid Mine Drainage (AMD) 1/3 of EPA Superfund Sites in Colorado are devoted to cleaning up abandoned mines. Characteristics: - low pH - high metal concentrations - elevated sulfate levels - excessive suspended solids Heavy Metals: Fe, Mn, Al

Geochemical processes: (1) 4FeS 2 (s) + 14O 2 (g) + 4H 2 O(l)  4Fe SO H + (2) 4Fe 2+ + O 2 (g) + 4H > 4Fe H2O(l) (3) 4Fe H 2 O(l)  4Fe(OH) 3 (s) + 12H + (4) 4FeS 2 (s) + 15O 2 (g) + 14H 2 O(l)  4Fe(OH) 3 (s) + 8SO H + pyrite “yellow boy” Acidophilic bacteria

Coal Creek Watershed Gunnison County, CO

Benthic Macroinvertebrates Stoneflies, Order Plecoptera: sensitive Caddisflies, Order Trichoptera: moderately tolerant Mayflies, Order Ephemeroptera: sensitive

Past Research Will Clements, CSU: mayflies Susan Bautts, 2005 Drew Bryenton, REU 2004: Lefthand Creek. Brianna Shanklin, 2005: Coal Creek ??Axtmann, adkfjljajdf (metal speciation trend)

Hypotheses  Elevated metal concentrations and reduced diversity and abundance of macroinvertebrates after Elk Creek Tributary, Iron Fen Drainages, Mt. Emmons Effluent. Correlations between sediments and benthic macroinvertebrate metal content. Concentrations will follow metal speciation trends. --take this out if I don’t have time?!

~CC-203 D/S of Elk ~CC ~CC-210 Iron Fen Drainages ~CC-218 U/S Mt. Emmons Affluent Wildcat Trail Bridge ~CC-119 D/S of drinking H 2 O inflow U/S of Elk CCUPUP D/S of Crested Butte Sample Sites along Coal Creek

Methods: Sampling June 14 & simultaneously with sediments. 13 sampling sites along 9.5km, starting point: 2005/Shanklin Injection Site. In Stream: kick and overturn rocks while dragging mess net behind. Emptied nets into buckets and trays and sorted stoneflies Stored in 60 ml bottles on ice until reached the lab

Methods: Sampling June 14 & simultaneously with sediments. 13 sampling sites along 9.5km, starting point: 2005/Shanklin Injection Site. In Stream: kick and overturn rocks while dragging mess net behind. Emptied nets into buckets and trays and sorted stoneflies Stored in 60 ml bottles on ice until reached the lab Frrrannnnnieeeee, give that back!

Frraaannie give that BACK!

Methods: Digestion Rinsed with Milli-Q water Dried in oven Measured dry weight Added Digestion solution: 1:1 soln. of 15.8M HNO 3 and 30% H 2 O 2 + H 2 O Shook in hot water bath Allowed to settle and supernatant removed and filtered with 0.45 µm nylon filters.

Methods: ICP-OES Diluted 9:1 solution Measured Metal Content with ICP-OES (ARD, Model 3410+) in the LEGS Lab, CU Boulder Measured Al, Cd, Cu, Fe, Mn, Pb, Zn concentrations in ppm.

Results

CHART!

U/S of Elk D/S of Elk D/S Mt E Effluent µg/g dry weight U/S Mt. Emmons Effluent Iron Fen Drainages

U/S of Elk D/S of Elk D/S Mt E Effluent µg/g dry weight U/S Mt. Emmons Effluent Iron Fen Drainages Distance (km)

D/S of Elk Iron Fen Drainages U/S Mt. E. Effluent D/S Mt. E. Effluent U/S of Elk µg/g dry wt. Distance (km)

µg/g dry weight D/S of Elk Iron Fen Drainages U/S Mt. E. Effluent D/S Mt. E. Effluent U/S of Elk Iron Concentrations (modified)

Distance (km) µg/g dry weight D/S of Elk Iron Fen Drainages U/S Mt. E. Effluent D/S Mt. E. Effluent U/S of Elk Iron Concentrations (modified)

D/S of Elk Iron Fen Drainages U/S Mt. E. Effluent D/S Mt. E. Effluent U/S of Elk µg/g dry weight Distance (km) Cu Concentrations Copper Concentrations

D/S of Elk Iron Fen Drainages U/S Mt. E. Effluent D/S Mt. E. Effluent U/S of Elk µg/g dry weight Distance (km) Cu Concentrations Copper Concentrations

Metal Concentrations (compiled) D/S of Elk Iron Fen Drainages U/S Mt. Emmons Effluent D/S Mt E Effluent U/S of Elk Creek µg/g dry weight Distance (km) Zn Fe Cu

Conclusions Elevated metal concentrations occur after Elk Creek, Mt. Emmons treatment plant effluent Benthic Macroinvertebrate populations affected directly after polluted inflow but then improved down the stream. High concentrations of iron in background site of stream.

Correlations to Frannie and Hallie’s data

Further Study Do some practice runs of the macroinvertebrate sampling before actually starting. Investigate fish populations Use ICP-MS for other metals found below detection limit.

Acknowledgements

Questions Scarlett Graham Allegheny College