Victoria County Station ESP Application Part 3 — Environmental Report Section 2.3 Table of Contents Section Title Page 2.3 Water ...................................................................................................................... 2.3-1 2.3.1 Hydrology ........................................................................................................... 2.3-1 2.3.1.1 Surface Water ......................................................................................... 2.3-2 2.3.1.2 Groundwater ......................................................................................... 2.3-40 2.3.2 Water Use ...................................................................................................... 2.3-139 2.3.2.1 Water Resources Planning and Appropriation .................................... 2.3-139 2.3.2.2 Groundwater Use ................................................................................ 2.3-141 2.3.2.3 Surface Water Use .............................................................................. 2.3-145 2.3.2.4 References .......................................................................................... 2.3-153 2.3.3 Water Quality ................................................................................................. 2.3-178 2.3.3.1 Groundwater ....................................................................................... 2.3-178 2.3.3.2 Surface Water .................................................................................... 2.3-180 2.3.3.3 References .......................................................................................... 2.3-185 2.3-i Revision 1 Victoria County Station ESP Application Part 3 — Environmental Report Section 2.3 List of Tables Number Title 2.3.1-1 Annual Peak Discharges for the Guadalupe River at Victoria, Texas USGS 08176500 2.3.1-2 Annual Peak Discharges for the San Antonio River at Goliad, Texas USGS 08188500 2.3.1-3 Annual Peak Discharges for the Coleto Creek near Victoria, Texas USGS 08177500 2.3.1-4 Guadalupe River Basin Dams (storage greater than 3000 acre-feet) 2.3.1-5 San Antonio River Basin Dams (storage greater than 3000 acre-feet) 2.3.1-6 USGS Stream Gages near VCS 2.3.1-7 Monthly Mean Flows for the Guadalupe River at Victoria, Texas USGS 08176500 2.3.1-8 Monthly Mean Flows for the San Antonio River at Goliad, Texas USGS 08188500 2.3.1-9 Monthly Mean Flows for Coleto Creek Near Victoria, Texas USGS 08177500 2.3.1-10 Mean Daily Flows for the Guadalupe River at Victoria, Texas, USGS Gage 08176500 2.3.1-11 Mean Daily Flows for the San Antonio River at Goliad, Texas, USGS Gage 08188500 2.3.1-12 Mean Daily Flows for Coleto Creek near Victoria, Texas, USGS Gage 08177500 2.3.1-13 Maximum of the Daily Mean Flows for the Guadalupe River at Victoria, Texas, USGS Gage 08176500 2.3.1-14 Maximum of the Daily Mean Flows for the San Antonio River at Goliad, Texas, USGS Gage 08188500 2.3.1-15 Maximum of the Daily Mean Flows for Coleto Creek near Victoria, Texas, USGS Gage 08177500 2.3.1-16 Minimum of the Daily Mean Flows for the Guadalupe River at Victoria, Texas, USGS Gage 08176500 2.3.1-17 Minimum of the Daily Mean Flows for the San Antonio River at Goliad, USGS Gage 08188500 2.3.1-18 Minimum of the Daily Mean Flows for Coleto Creek near Victoria, Texas, USGS Gage 08177500 2.3.1-19 Guadalupe River Peak Discharge Frequency at Confluence with Coleto Creek 2.3.1-20 Suspended Sediment Concentrations for the Guadalupe River at Victoria, Texas USGS Gage 08176500 2.3.1-21 Suspended Sediment Concentrations for the San Antonio River at Goliad, Texas USGS Gage 08188500 2.3-ii Revision 1 Victoria County Station ESP Application Part 3 — Environmental Report List of Tables (Cont.) Number Title 2.3.1.2-1 Observation Well Construction Details 2.3.1.2-2 Groundwater Observation and Test Wells Monitoring the Chicot Aquifer 2.3.1.2-3 VCS Monthly Groundwater Level Measurements 2.3.1.2-4 Vertical Hydraulic Gradient Calculations 2.3.1.2-5 VCS Site Slug Test Results 2.3.1.2-6 Summary of Aquifer Pumping Test Results 2.3.1.2-7 Hydrogeologic Properties from Geotechnical Tests 2.3.1.2-8 Summary Statistics for Hydrogeologic Properties from Geotechnical Tests 2.3.1.2-9 Grain-Size Derived Hydraulic Conductivity 2.3.1.2-10 Laboratory Hydraulic Conductivity Test 2.3.1.2-11 VCS Cooling Basin Permeability Values from Borehole Permeameter Tests 2.3.1.2-12 Regional Hydrogeochemical Data 2.3.1.2-13 VCS Site Hydrogeochemical Data 2.3.1.2-14 Estimated Cooling Basin Seepage 2.3.1.2-15 Summary of Particle Tracking Analysis 2.3.1.2-16 Summary of Locations Where Confining Layers are Absent 2.3.2-1 Groundwater Use (Acre-Feet per Year) by County in 50-Mile Radius of VCS Site (2004) 2.3.2-2 Available and Allocated Groundwater Supplies (Acre-Feet per Year) in Victoria County, Texas (2000–2060) 2.3.2-3 Available and Allocated Groundwater Supplies (Acre-Feet/Year) in Calhoun County, Texas (2000–2060) 2.3.2-4 Available and Allocated Groundwater Supplies (Acre-Feet per Year) in Refugio County, Texas (2000–2060) 2.3.2-5 TWDB Wells Located Within 6 Miles of the VCS Site 2.3.2-6 TCEQ Public Water Supply Wells Located Within 10 Miles of the VCS Site 2.3.2-7 Surface Water Use (Acre-Feet per Year) by County in 50-Mile Radius of the VCS Site (2007) 2.3.2-8 List of major Guadalupe River Basin Reservoirs 2.3.2-9 Surface Water Users in Victoria County 2.3.2-10 Surface Water Users in Calhoun County 2.3.2-11 Surface Water Users in Goliad County 2.3.2-12 Summary of GBRA/UCC Water Rights in the Lower Guadalupe River Basin 2.3.2-13 GBRA Record of Reported Calhoun Canal Water Use and Availability 2.3-iii Revision 1 Victoria County Station ESP Application Part 3 — Environmental Report List of Tables (Cont.) Number Title 2.3.2-14 Projected Surface Water Demands, Supplies, and Needs for Victoria and Calhoun Counties (Acre-Feet per Year) (2000–2060) 2.3.2-15 Comparison of 1990–2009 Historical Droughts to the 1950s Drought of Record 2.3.3-1 Summary of Groundwater Quality Data for TWDB Wells Located within 6 Miles of the VCS Site 2.3.3-2 Summary of Exelon Victoria County Onsite Groundwater Analytical Results 2.3.3-3 Summary of Exelon Victoria County Offsite TWDB Well #7932602 Groundwater Analytical Results (03/25/08) 2.3.3-4 TCEQ Water Quality Segment Designated Uses 2.3.3-5 Summary of USGS and TCEQ Surface Water Monitoring Stations 2.3.3-6 Summary of Guadalupe River at GBRA Saltwater Barrier (TCEQ Station 12578) Surface Water Metals Data (1999–2006) 2.3.3-7 Summary of Guadalupe River at GBRA Saltwater Barrier (TCEQ Station 12578) Surface Water General Chemistry Data (2004–2007) 2.3.3-8 Summary of Guadalupe River Near Dupont Invista (TCEQ Station 16579) Surface Water General Chemistry Data (2003–2006) 2.3.3-9 Summary of Guadalupe River at Highway 77 (TCEQ Station 12590) Surface Water General Chemistry Data (2004–2007) 2.3.3-10 Summary of Guadalupe River Tidal (TCEQ Station 12577) Surface Water Quality Data (2002–2007) 2.3.3-11 Summary of Guadalupe River at GBRA Saltwater Barrier (USGS Station 08188800) Water Quality Data (1980–1999) 2.3.3-12 Summary of Guadalupe River at Victoria (USGS Station 08176500) Water Quality Data (1980–1999) 2.3.3-13 Summary of Guadalupe River at Highway 59 (TCEQ Station 12581) Water Quality Data (1990–1994) 2.3.3-14 Summary of Lower San Antonio River at Highway 77 (TCEQ Station 12789) Water Quality Data (2003–2007) 2.3.3-15 Summary of GBRA Calhoun Canal Uplift Station #1 (USGS Station 08188600) Water Quality Data (1995–2005) 2.3.3-16 Summary of Victoria Barge Canal (TCEQ Station 12536) Water Quality Data (2004–2007) 2.3.3-17 Summary of Coleto Creek at Highway 77 (TCEQ Station 12622) Water Quality Data (1994–1997) 2.3.3-18 VCS Site Surface Water Analytical Results 2.3.3-19 TPDES Sites in Lower Guadalupe and Lower San Antonio River Basins (Victoria, Refugio, and Goliad Counties) 2.3-iv Revision 1 Victoria County Station ESP Application Part 3 — Environmental Report Section 2.3 List of Figures Number Title 2.3.1-1 Victoria County Station Location Map 2.3.1-2 Guadalupe and San Antonio River Basin Watersheds 2.3.1-3 Guadalupe River Basin Dams 2.3.1-4 San Antonio River Basin Dams 2.3.1-5 VCS Site Floodplain Map 2.3.1-6 Guadalupe and San Antonio River Basins: Selected Stream Gages 2.3.1-7 Victoria County Station Blowdown Discharge Location Map 2.3.1-8 Guadalupe River Bathymetry—200 Feet Upstream of Blowdown Discharge Location 2.3.1-9 Guadalupe River Bathymetry—Near Blowdown Discharge Location 2.3.1-10 Guadalupe River Bathymetry – 500 Feet Downstream of Blowdown Discharge Location 2.3.1-11 Existing Streams and Wetlands 2.3.1-12 Victoria County Station, Raw Water Makeup (RWMU) System Intake Location Map 2.3.1-13 Guadalupe River Bathymetry — Near Raw Water Makeup System Intake Channel Location 2.3.1.2-1 Regional Site Location Plan 2.3.1.2-2 Physiographic Map of Texas 2.3.1.2-3 Detailed Site Location Plan 2.3.1.2-4 Major Aquifers of Texas 2.3.1.2-5 Correlation of USGS and Texas Nomenclature 2.3.1.2-6 Generalized Cross Section through the Coastal Lowlands/Coastal Uplands Aquifer Systems 2.3.1.2-7 Regional Hydrogeologic Cross Section through the Gulf Coast Aquifer System 2.3.1.2-8 Sole Source Aquifers EPA Region 6 2.3.1.2-9 Regional Potentiometric Surface Map for the Chicot Aquifer, including Water Level Measurements from 2001 to 2005 (Sheet 1 of 2) 2.3.1.2-9 Regional Potentiometric Surface Map for the Chicot Aquifer, including Water Level Measurements from 2001 to 2005 (Sheet 2 of 2) 2.3.1.2-10 VCS Site Well Location Plan 2.3.1.2-11 1999 Potentiometric Surface