LAKE FORK OF THE GUNNISON RIVER WATERSHED: WATER QUALITY DATA ANALYSIS AND SUMMARY

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1 LAKE FORK OF THE GUNNISON RIVER WATERSHED: WATER QUALITY DATA ANALYSIS AND SUMMARY By: Ashley Bembenek July 21, 2011

2 Lake Fork Watershed 3 sub-watersheds Upper Lake Fork (ULF) Henson Creek (HC) Lower Lake Fork (LLF)

3 WATERSHED CHARACTERISTICS

4 REGULATORY FRAMEWORK 6 Regulatory Segments in the Lake Fork Watershed COGUUG 29a COGUUG 29a-DG COGUUG 29b COGUUG 29a COGUUG 31 COGUUG 32

5 (d) DATA CALL SUMMARY

6 WATER QUALITY EVALUATION RESULTS Upper Lake Fork: most locations sampled once Henson Creek: most frequently sampled. Most sites 1-3 times Lower Lake Fork: sample frequency varies widely

7 WATER QUALITY MONITORING BY SITE TYPE

8 WATER QUALITY STANDARD EVALUATION RESULTS

9 WATER QUALITY STANDARD EVALUATION RESULTS Zero exceedances for: Ammonia- Acute Ammonia-Chronic Arsenic-Acute Chloride Chromium III- Acute Chromium IV-Acute Chromium IV-Chronic E. Coli Mercury-Chronic Nickel-Acute Nitrate Nitrite Selenium-Acute

10 WATER QUALITY STANDARD EVALUATION RESULTS: Ten Most Problematic Pollutants and Number of Exceedances

11 WATER QUALITY EXCEEDANCES BY SUB-WATERSHED 65%

12 COMPARISON TO COLORADO 305(b) REPORT: RIVERS State of the Water report to the EPA 5 Most Common Pollutants in CO Selenium E. Coli Copper Iron Zinc 5 Most Common Pollutants in Lake Fork Watershed Aluminum Zinc Cadmium Manganese Iron

13 COMPARISON TO COLORADO 305(b) REPORT: LAKES State of the Water report to the EPA 5 Most Common Pollutants in CO Mercury Selenium Dissolved Oxygen Nitrate ph Lake San Cristobal Manganese sometimes exceeds water quality standards Mercury has not been measured in the lake Selenium, Dissolved Oxygen, ph and Nitrate are excellent with respect to regulatory criteria

14 2010 WATER QUALITY MONITORING OBJECTIVES FOUR FOCUS AREAS

15 2010 WATER QUALITY MONITORING OBJECTIVES LAKE SAN CRISTOBAL Manganese is the only water quality impairment Secondary water standard Yes, Al, As, Cd, Cu, Fe, Mn, Ni, SO4, and Zn Yes, Al, Cd, Cu, Fe, Mn, Ni, SO4, and Zn ph also problematic Measured nutrient concentrations do NOT suggest contamination of any kind

16 2010 WATER QUALITY MONITORING OBJECTIVES LAKE CITY REACH Cadmium, zinc & aluminum are the most problematic metals E. Coli concentrations are well below the state standard and are not a management concern at this time. 3 samples collected in 2010

17 2010 WATER QUALITY MONITORING OBJECTIVES HENSON CREEK This report supports previous findings. Palmetto Gulch is the most problematic drainage Discussion to follow

18 HENSON CREEK: ROY PRAY RECLAMATION EFFORTS Reclamation work to date: 2003: Bulkhead sealed at Roy Pray Adit 2005: Adit waste pile relocated and re-graded Seeps have developed near the bulkhead and around the adit since Four areas evaluated: Above Roy Pray Roy Pray Mine Below Roy Pray Mine Below: Palmetto Gulch

19 HENSON CREEK: ROY PRAY RECLAMATION EFFORTS Water Quality through Time Cd concentrations above the Roy Pray and in Palmetto Gulch have remained relatively stable through time Cd concentrations at Roy Pray & Immediately below the mine initially declined, but have begun to increase in recent years

20 HENSON CREEK: ROY PRAY RECLAMATION EFFORTS Water Quality through Time Above Roy Pray Roy Pray Mine Below Roy Pray Below: Palmetto Gulch Dissolved Copper (ug/l) Cu concentrations in Palmetto Gulch have remained relatively stable through time Cu concentrations elsewhere have increased over time 10 Increases in above and in the mine 5 0 do NOT account for all of increases measured immediately below the mine 2010 data from below the Roy Pray has the highest Cu concentrations measured to date Water from the new seeps appears to interact with mine pool water or other low quality water--- Cu concentrations are very high

21 HENSON CREEK: ROY PRAY RECLAMATION EFFORTS Water Quality through Time 14,000 12,000 10,000 8,000 6,000 4,000 2,000 0 Dissolved Zinc (ug/l) Above Roy Pray Roy Pray Mine Below Roy Pray Below: Palmetto Gulch Zn concentrations above Roy Pray & in Palmetto Gulch have remained relatively stable through time Zn concentrations initially declined After the bulkhead was sealed at the Roy Pray Mine Since 2006, Zn concentrations have been on the rise at the mine and immediately below it

22 HENSON CREEK: ROY PRAY RECLAMATION EFFORTS Metal concentrations on the rise, what has flow done? Location Year 2000 Flow (cfs) Month July June September June July Above Roy Pray Roy Pray 0.03 NM NM Below Roy Pray Below: Palmetto Gulch NM NM Flow from Roy Pray Mine may be similar to pre-reclamation levels Flow below Roy Pray has likely increased over pre-reclamation levels Currently, metal loads are lower than pre-reclamation loads However, there is little evidence to suggest chemical or hydrologic stability at this location ADDITIONAL DATA IS NEEDED TO BETTER UNDERSTAND CURRENT CONDITIONS- Collect data from Palmetto Gulch as well

23 HENSON CREEK: UTE-ULAY RECLAMATION EFFORTS Reclamation Project: Tailings Removal Surface Contouring Topsoil Placement Reclamation seeding to increase site and slope stability Completed during 2009 and 2010

24 HENSON CREEK: UTE-ULAY RECLAMATION EFFORTS Has reclamation improved water quality? Above Ute-Ullay: Cd dis Above Ute-Ullay: Cd tot Below Ute-Ullay: Cd dis Below Ute-Ullay: Cd tot Above Ute-Ullay: Cu dis Above Ute-Ullay: Cu tot Below Ute-Ullay: Cu dis Below Ute-Ullay: Cu tot Above Ute-Ullay: Zn dis Above Ute-Ullay: Zn tot Below Ute-Ullay: Zn dis Below Ute-Ullay: Zn tot Cadmium concentrations generally low and stable above and below Ute- Ulay In 2010, copper concentrations declined from 2008 values both above and below Ute-Ulay In 2010, zinc concentrations declined from 2008 and 2005 values both above and below Ute-Ulay Declines measured below mine exceed declines measured above the Ute-Ulay Yes, the reclamation project has improved water quality

25 2010 WATER QUALITY MONITORING OBJECTIVES LOWER LAKE FORK Measured nutrient concentrations do not suggest contamination of any kind Specific land uses do not appear to impact water quality in this reach No. Highest E. coli concentration measured to date is 37 col/100ml State standard 126 col/100ml

26 QUESTIONS? COMMENTS? ETC...