Where does water from Champaign Urbane come from A B C D E Groundwater Contamination CEE 330 8 6 and lecture notes Mississippi river Lake Michigan Mahomet aquifer Clinton aquifer None of the above 1 2 How does the groundwater move Introduction to groundwater movie up to 4 min flow from 4 min to 10 25 min contamination A Groundwater infiltrates through layers of sediments B Groundwater moves from high hydraulic head where recharge area is to low hydraulic head where the discharge area is C Groundwater is NOT connected with surface water D A and B E B and C 3 4 Darcy s law Hydraulic gradient Q KA dh dL Q KA dh dL K dh dL A A K hydraulic conductivity Darcy velocity v K dh dL actual velocity v Porosity Darcy velocity v 5 6 1 Two groundwater wells are located 100 m apart in permeable sand and gravel The water level in well 1 is 50 m below the surface and in well 2 the water level is 75 m below the surface The hydraulic conductivity is 1 m day and porosity is 0 6 What is 1 The Darcy s velocity Porosity Porosity volume of voids total volume of solids and voids Material Porosity Clay Sand 45 34 Specific Yield 3 25 Gravel 25 Gravel and sand 20 22 16 Sandstone 8 15 7 8 Two groundwater wells are located 100 m apart in permeable sand and gravel The water level in well 1 is 50 m below the surface and in well 2 the water level is 75 m below the surface The hydraulic conductivity is 1 m day and porosity is 0 6 What is 2 The true velocity 9 10 Two groundwater wells are located 100 m apart in permeable sand and gravel The water level in well 1 is 50 m below the surface and in well 2 the water level is 75 m below the surface The hydraulic conductivity is 1 m day and porosity is 0 6 What is 3 The period it takes water to travel between two wells 11 12 2 What is groundwater used for A B C D E Drinking water supply Irrigation Bottle water Electronic industry All of the above 13 Groundwater level Vermilion County Illinois 14 Groundwater level Cochise County Arizona 15 Besides moving with the flow what else will happen to the chemical in groundwater A It can be degraded by bacteria B It can be degraded by reacting with other chemicals in the soil C It can sorb to the organic carbon fraction of the soil D All of the above E None of the above 17 16 Woburn Massachusetts Case Study movie A Civil Action True story about a hazardous waste site in Woburn MA Chemical pollutant is trichloroethylene TCE Long history of chemical manufacturing and leather tanning 18 3 Woburn Massachusetts Case Study movie A Civil Action 1 2 3 4 5 What is the problem Who is affected by the problem Who is now involved What do you already know about the case Be careful not to confuse things that we know with things that we assume What can you do to help solve the case List the things that you would like to test How should we test the water to determine where the TCE came from Where should we start What variables should we take into consideration How could you be sure about who caused the contamination 19 20 Dr Norm Jones at Brigham Young University Contaminant transport in subsurface Soil sorption coefficient Koc groundwater flow Soil carbon Koc K monitoring well Contaminant source water Ctotalsoil K oc f oc Cw non retarded plume moving with groundwater flow Ctotalsoil K oc f oc Cw Cw Ctotalsoil K oc f oc 21 Contaminant transport in subsurface Retardation How much slower will contaminant move groundwater flow groundwater flow Contaminant source 22 monitoring well Contaminant source monitoring well retarded plume Sorption causes slower movement Retardation factor R retarded plume Sorption causes slower movement K f Average groundwater velocity v Average velocity of the sorbed chemical vs 1 oc oc B K oc Soil sorption coefficient f oc fraction of organic carbon in soil sediment 23 porosity B density of soil sediment 24 4 A typical value of subsurface porosity is 0 3 and soil bulk mass density is 2 1g cm3 the subsurface material s fraction of organic carbon is 0 01 foc 0 01 Epiwin gives Koc for CTET 48 64 and Koc for PCE 106 8 Which contaminant CTET or PCE moves slower Retardation factor R K f Average groundwater velocity v 1 oc oc B Average velocity of the sorbed chemical vs K oc Soil sorption coefficient f oc fraction of organic carbon in soil sediment porosity B density of soil sediment START FROM THE QUESTION FIND KEY EQUATION 25 26 27 28 29 30 A typical value of subsurface porosity is 0 3 and soil bulk mass density is 2 1g cm3 the subsurface material s fraction of organic carbon is 0 01 foc 0 01 Epiwin gives Koc for CTET 48 64 and Koc for PCE 106 8 Which contaminant CTET or PCE moves slower A typical value of subsurface porosity is 0 3 and soil bulk mass density is 2 1g cm3 the subsurface material s fraction of organic carbon is 0 01 foc 0 01 Epiwin gives Koc for CTET 48 64 and Koc for PCE 106 8 If the hydraulic conductivity is 10 3 cm sec and the hydraulic gradient of 0 001 how much faster will a plume of CTET move than a plume of PCE START FROM THE QUESTION FIND KEY EQUATION 5 A typical value of subsurface porosity is 0 3 and soil bulk mass density is 2 1g cm3 the subsurface material s fraction of organic carbon is 0 01 foc 0 01 Epiwin gives Koc for CTET 48 64 and Koc for PCE 106 8 If the hydraulic conductivity is 10 3 cm sec and the hydraulic gradient of 0 001 how much faster will a plume of CTET move than a plume of PCE 31 32 Toluene is spilled to an aquifer at the rate of 100ml day fraction of organic carbon foc 10 actual groundwater v 0 01 m d porosity 0 34 the hydraulic gradient 0 0005 bulk density of the sand B 1600 kg m3 Density of toluene is 0 862 g mL Data for toluene from EPIWIN Water Sol 526 mg L 25 deg C Soil Adsorption Coefficient PCKOCWIN v1 66 Koc 268 chloride non sorbing tracer carbon tetrachloride CTET Koc 48 64 tetrachloroethylene PCE Koc 106 8 1 Find hydraulic conductivity 33 1 Hydraulic conductivity of the aquifer 34 2 What is retardation factor R 35 36 6 4 Assume the dissolved toluene distributes uniformly in the aquifer and forms a plume 2 0 m wide 4 0 m deep and extending as far as you calculated What is the average toluene concentration in 4m the plume Is there a separate phase What is mass of this phase 3 How far would you expect toluene to have traveled down …