1. WASP7 Course Organic Chemical Model Summary of Process Equations and Model Input Data

2. Watershed & Water Quality Modeling Technical Support Center WASP7 Course Aquatic Transport, Speciation and Transformation Processes

3. Watershed & Water Quality Modeling Technical Support Center WASP7 Course TOXI Organic Chemical Processes Equilibrium ProcessesEquilibrium Processes –Sorption –Ionization Kinetic ProcessesKinetic Processes –Volatilization –Photolysis –Hydrolysis –Bacterial Degradation –Oxidation –Reduction

4. Watershed & Water Quality Modeling Technical Support Center WASP7 Course Sorption - Desorption ReactionReaction –Movement of chemical between the dissolved phase and particulate or solid phase. The chemical may be physically associated or chemically bound to functional groups on the solid. Linear Partitioning EquationLinear Partitioning Equation DataData –Partition coefficient (K p, K oc, or K ow ), L w /kg S –Solids concentration, mg/L –Solids organic fraction

5. Watershed & Water Quality Modeling Technical Support Center WASP7 Course Ionization ReactionReaction –Dissociation of neutral parent molecule into ionic species –Weak acid − Weak base Equilibrium EquationsEquilibrium Equations DataData –pK ai, negative log of K ai –pK bi, negative log of K bi –pH, negative log of [H + ]

6. Watershed & Water Quality Modeling Technical Support Center WASP7 Course Volatilization DataData –Atmospheric concentration, g/m 3 –Depth (surface area/volume), m –Henry’s Law constant, atm/molar –Water temperature, kelvin –Conductivity, k v, m/day Function of depth, current velocity and wind speed, m/sec ReactionReaction –Movement of dissolved chemical between water and air Kinetic EquationKinetic Equation

7. Watershed & Water Quality Modeling Technical Support Center WASP7 Course Photolysis DataData –Surface photolytic rate constant, k ps, day -1 –Latitude and reference latitude, degrees –Light intensity at surface –Depth (surface area/volume), m –Light extinction coefficient, m -1 Measured, or function of chl a, DOC, S ReactionReaction –Degradation of dissolved chemical by sunlight KineticKinetic Equation Equation

8. Watershed & Water Quality Modeling Technical Support Center WASP7 Course Hydrolysis ReactionReaction Kinetic EquationKinetic Equation DataData –pH –k H or k Hn, day -1 –k Ha, molar -1 day -1 –k Hb, molar -1 day -1

9. Watershed & Water Quality Modeling Technical Support Center WASP7 Course Bacterial Degradation ReactionReaction KineticKinetic Equation Equation DataData –k BW or k BS, day -1 –k B, (cells/mL) -1 day -1 –bacterial population density, bac, (cells/mL)

10. Watershed & Water Quality Modeling Technical Support Center WASP7 Course Oxidation ReactionReaction KineticKinetic Equation Equation DataData –k OX, day -1 –k O, (moles/L) -1 day -1 –oxidant concentration, oxrad, (moles/L)

11. Watershed & Water Quality Modeling Technical Support Center WASP7 Course Reduction ReactionReaction KineticKinetic Equation Equation DataData –k EX, day -1 –k E, (moles/L) -1 day -1 –reductant concentration, exrad, (moles/L)

12. Watershed & Water Quality Modeling Technical Support Center WASP7 Course Organic Toxicant Time Functions Water temperature (4) (degrees C)Water temperature (4) (degrees C) Water velocity (4) (m/sec)Water velocity (4) (m/sec) pH of water column & benthic segmentspH of water column & benthic segments Normalized light intensity (photolysis option 2)Normalized light intensity (photolysis option 2) Wind speed at 10 meters (m/sec)Wind speed at 10 meters (m/sec) Bacteria population (Water & Benthos)Bacteria population (Water & Benthos) Air temperature (degrees C)Air temperature (degrees C) Reaeration rate constant (day -1 )Reaeration rate constant (day -1 ) Chlorophyll-a (mg/L)Chlorophyll-a (mg/L)

13. Watershed & Water Quality Modeling Technical Support Center WASP7 Course Organic Toxicant Segment Parameters Water velocity time function pointerWater velocity time function pointer Water temperature (time function pointer and multiplier)Water temperature (time function pointer and multiplier) Wind speed multiplierWind speed multiplier Reaeration rate multiplierReaeration rate multiplier Dissolved organic carbon, DOC (mg/L)Dissolved organic carbon, DOC (mg/L) Fraction organic carbon for solids 1, 2, 3 (fraction)Fraction organic carbon for solids 1, 2, 3 (fraction) Chlorophyll a concentration (mg/L)Chlorophyll a concentration (mg/L) pHpH Light extinction coefficient (meter -1 )Light extinction coefficient (meter -1 ) Bacteria Population (cells/100 mL)Bacteria Population (cells/100 mL) Oxidative radical concentration (moles/L)Oxidative radical concentration (moles/L) Extra environmental property (e.g., reductant, moles/L)Extra environmental property (e.g., reductant, moles/L) Overall decay rate constant for chemicals 1, 2, 3 (day -1 )Overall decay rate constant for chemicals 1, 2, 3 (day -1 )

14. Watershed & Water Quality Modeling Technical Support Center WASP7 Course Organic Toxicant Constants Constants GroupsConstants Groups –Solids –Ionization –Sorption –Volatilization –Hydrolysis –Photolysis –Biodegradation –Oxidation –Reduction Notes on Listing –Constants are listed by group for Non-Ionic Toxicant module –In the general Organic Toxicant Module, these constants are repeated for each of 5 ionic species –Chemical 1 constants are shown; these are repeated for chemicals 2 and 3

15. Watershed & Water Quality Modeling Technical Support Center WASP7 Course Sorption Constants

16. Watershed & Water Quality Modeling Technical Support Center WASP7 Course Volatilization Constants

17. Watershed & Water Quality Modeling Technical Support Center WASP7 Course Hydrolysis Constants

18. Watershed & Water Quality Modeling Technical Support Center WASP7 Course Hydrolysis Constants, cont’d

19. Watershed & Water Quality Modeling Technical Support Center WASP7 Course Photolysis Constants

20. Watershed & Water Quality Modeling Technical Support Center WASP7 Course Biodegradation Constants

21. Watershed & Water Quality Modeling Technical Support Center WASP7 Course Oxidation Constants

22. Watershed & Water Quality Modeling Technical Support Center WASP7 Course Reduction Constants

23. Watershed & Water Quality Modeling Technical Support Center WASP7 Course Ionization Constants

24. Watershed & Water Quality Modeling Technical Support Center WASP7 Course Additional Oxidation Constants for Ionic Chemical