Tennessee Valley Authority · NYSE:TVC
Tennessee Valley Authority — Technical Presentation (August 2011)
14 slides from Tennessee Valley Authority's technical presentation, Aug 3, 2011
Slide 1: The Complexity of Reservoir Benthic Habitats: Effects of the Kingston Fly Ash Release
The Complexity of Reservoir Benthic Habitats: Deciphering the Effects of the Kingston Fly Ash Release on the Benthic Macroinvertebrate Community TVA Symposium | August 3, 2011 Tyler Baker Tennessee Valley Authority John Smith Oak Ridge National Laboratory
Slide 2: Sampling Method
Sampling Method • 11 sites, January 2009 • 13 sites, Ash December 2009 Release Site • 15 sites, December 2010
Slide 3: Sampling Method
Sampling Method
Slide 4: Mean Population Density
Mean Population Density 3500 3000 Number / m2 2500 2000 1500 1000 500 3 3 2 1 1 2 3 3 3 3 3 3 3 3 3 3 0 TRM 573.9 TRM 566.3 ERM 6.0 ERM 5.0 ERM 4.1 ERM 3.0 ERM 2.6 ERM 2.2 ERM 1.0 **TRM 560.8 CRM 8.7 CRM 6.0 CRM 4.0 CRM 3.0 CRM 1.5 CRM 0.5 Emory Clinch Tenn Site Mean (± Min and Max) "Reference" Site
Slide 5: Mean Taxa Richness
Mean Taxa Richness 55 50 45 40 Number of Taxa 35 30 25 20 15 10 5 3 3 2 1 1 2 3 3 3 3 3 3 3 3 3 3 0 ** TRM 560.8 TRM 573.9 TRM 566.3 CRM 8.7 CRM 6.0 CRM 4.0 CRM 3.0 CRM 1.5 CRM 0.5 ERM 6.0 ERM 5.0 ERM 4.1 ERM 3.0 ERM 2.6 ERM 2.2 ERM 1.0 Emory Clinch Tenn Site Mean (± Min and Max) "Reference" Sites *
Slide 6: Summary of Benthic Macroinvertebrate Composition
Summary of Benthic Macroinvertebrate Composition Composition Taxa Group # Organisms # Taxa Density Taxa Mayfly 25 6 0.1% 3.7% Hexagenia sp. 3,500 1 9% 0.6% EPTs Stonefly 5 2 0.0% 1.2% Caddisfly 100 8 0.2% 4.9% Sphaerid Clams 4,200 2 10% 1.2% Oligochaetes 13,100 20 32% 12.3% Chironomids 15,300 73 38%
Slide 7: Mean Density of Dominant Taxa Groups
Mean Density of Dominant Taxa Groups Mean Density (± SE) "Reference" Sites
Slide 8: Cross-sectional Area
Cross-sectional Area (ft2) 5000 0 10000 15000 20000 25000 30000 35000 ERM 6.0 ERM 5.0 ERM 4.1 Emory ERM 2.2 ERM 1.0 SITE CRM 8.7 CRM 6.0 Cross-sectional Area CRM 4.0 Emory and Clinch Rivers Clinch CRM 3.0 CRM 1.5 CRM 0.5
Slide 9: Ash Thickness in Rivers
Ash Thickness in Rivers Ash Thickness (feet) Ash Thickness Profile ERM 6 ERM 0 TRM 563 30.00 25.00 N = f=) f=} 15.00 | 10.00 5.00 0.00 “3.50 -250 -1.50 -0.50 0.50 1.50 2.50 3.50 4.50 5.50 6.50 7.50 8.50 950 10.50 11.50 Distance From Spill (miles) Spill : Downstream Location Upstream
Slide 10: Kingston Ash Recovery
Kingston Ash Recovery Benthic Community Waypoints © Benthic Community Waypoints Phase 1 Dredge Area 2,000 4,000 Feet Photography Date: 04/11/2010 Map Compiled 07/27/2011 Tennessee Valley Authority Geographic Information & Engineering DredgeAreas_and Benthic 2010_20110727_ 1h pat
Slide 11: Population Density, Substrate, and Water Depth, December 2009
Population Density, Substrate, and Water Depth Emory River Mile 2.2, December 2009 3500 100 Detritus 90 3000 80 Ash 2500 70 Substrate (%) Ash Density (#/m2) 60 2000 Fines Detritus Detritus Ash Ash 50 Fines Fines 1500 Detritus 40 1000 30 Fines 20 500 Fines 10 Fines Fines 0 Fines 0 3 4.7 4.8 6.5 6.8 7
Slide 12: Population Density, Substrate, and Water Depth, December 2010
Population Density, Substrate, and Water Depth Emory River Mile 2.2, December 2010 7000 100 Detritus Ash 90 6000 Ash Ash 80 5000 70 Detritus Substrate (%) Density (#/m2) Ash Detritus 60 4000 Detritus HP Clay HP Clay Fines Fines 50 3000 Fines 40 Fines 30 2000 20 Fines Gravel 1000 Fines Fines Fines 10
Slide 13: Summary
Summary • Benthic community differences among sites clearly exist. • Differences appear to be primarily related to variations in channel morphology and the complexity of converging river systems with different hydrological, physical and chemical characteristics. • No historical benthic macroinverteb
Slide 14: Questions?
QUESTIONS?
Tennessee Valley Authority — Technical Presentation (August 2011) on 6ix