1. Mitigation of Pollution in Nursery Runoff J.N. Kabashima, Darren Haver, Jay Gan, and L. Wu

2. Mitigating Pollutants in Nursery Runoff Water  Proactive Participate in the process Participate in the process Get involved individually and as part of an industry group or association.Get involved individually and as part of an industry group or association. Have data before you need it. Have data before you need it. Help develop solutions and regulations. Help develop solutions and regulations. Identify and seek sources of information and expertise. Identify and seek sources of information and expertise.  Reactive Try to figure out how to comply with regulations and or litigation. Try to figure out how to comply with regulations and or litigation.

3. Mitigating Pollutants in Nursery Runoff Water  Conduct a Self-Assessment Runoff and NPS Self-Assessment http://cesandiego.ucdavis.edu/Clean%5FWater/ http://cesandiego.ucdavis.edu/Clean%5FWater/ http://cesandiego.ucdavis.edu/Clean%5FWater/  Identify Management options Management Options for NPS Pollution http://ucce.ucdavis.edu/files/filelibrary/2017/10391.pdf http://ucce.ucdavis.edu/files/filelibrary/2017/10391.pdf http://ucce.ucdavis.edu/files/filelibrary/2017/10391.pdf  Document Efforts Water Quality Record Keeping http://ucce.ucdavis.edu/files/filelibrary/2017/8453.PDF http://ucce.ucdavis.edu/files/filelibrary/2017/8453.PDF

4. Self-Assessment Property Management Property Management Road Management Road Management Irrigation Practices Irrigation Practices Leaching & Runoff Leaching & Runoff Nutrient Assessment & Fertilizer Management Nutrient Assessment & Fertilizer Management Integrated Pest Management Integrated Pest Management

5. Management Options for NPS Pollution Greenhouse and Container Crop Industries Irrigation Management and Water Quality Irrigation Management and Water Quality Nutrients Nutrients Integrated Pest Management (IPM) Integrated Pest Management (IPM)

6. Water Quality Record Keeping Sites Mats and Emergency Information Sites Mats and Emergency Information Hazardous Materials Hazardous Materials Sanitation & Waste Management Sanitation & Waste Management Pesticide Use Pesticide Use Fertilizer Use Fertilizer Use Irrigation Practices & Runoff Management Irrigation Practices & Runoff Management Equipment Maintenance Equipment Maintenance Best Management Practices/Mgmt Options Best Management Practices/Mgmt Options Employee Training =/Education Employee Training =/Education Reports, Data, & Other Information Reports, Data, & Other Information

7. Irrigation Management and Water Quality  Monitor Water Quality  Maximize Irrigation Efficiency  Irrigation Scheduling  Select Appropriate Growing Medium  Consider the Use of Wetting Agents  Reduce Leaching  Publications on New Technologies  Continuing Education  Collect, Treat and Recycle Open Runoff/Tailwater Recovery  Collect Runoff from Outdoor Production Areas

8. Irrigation Management and Water Quality  Collect Runoff from Field Drains and Non- Concrete Floors  Further Aspects of Reusing Water  Erosion/Drainage Control & Water Conservation  Water Conservation  Management Practices  Excess Water Removal  Pathogen Detection and Control  Cost-sharing  Municipal Treatment Plants

9. Irrigation Management and Water Quality  Maximize Irrigation Efficiency  Irrigation Scheduling  Select Appropriate Growing Medium  Consider the Use of Wetting Agents  Collect, Treat and Recycle Open Runoff/Tailwater Recovery  Pathogen Detection and Control  Continuing Education

10. Irrigation Management and Water Quality Maximize Irrigation Efficiency Irrigation Scheduling

11. Irrigation Management and Water Quality Select Appropriate Growing Medium Consider the Use of Wetting Agents

12. Irrigation Management and Water Quality Collect, Treat and Recycle Open Runoff/Tailwater Recovery Pathogen Detection and Control

13. Irrigation Management and Water Quality Continuing Education

14. Outline – El Modeno Gardens Case Study  How does it happen? Self-Assessment Self-Assessment  What type of mitigation practices can be implemented? Management Practices Management Practices

15. How Does It Happen?  Irrigation (carrier)  Planting Media (source) Runoff + planting media = pesticide runoff?

16. IrrigationIrrigation

17. Planting Media

18. Nursery Runoff Runoff!

19. Step 1: Scrap off surface soil Step 2: Estimate potting mix content Step 3: Analyze pesticides Step 4: Correlation Step 1: Scrap off surface soil Step 2: Estimate potting mix content Step 3: Analyze pesticides Step 4: Correlation

20. Bifenthrin (Talstar) in Spilled Potting Mix

21. Potting Mix Spills

22. Mitigation Practices  Reduce Irrigation Runoff  On-site solid removal: PAM PAM In-line sediment trap In-line sediment trap Collection pond Collection pond Vegetative filtration Vegetative filtration Adsorptive filters Adsorptive filters  Capture and Recycle Runoff Treat recaptured water Treat recaptured water

23. AdsorptionAdsorption DOC DOC- Adsorbed DOC-complex Dissolved

24. “Muddy” Runoff

25. 104 m 262 m (reservoir or exit) 0 m 145 m 166 m 187 m 210 m 240 m Sediment Trap Production Area PAM Tablets Sediment Pond Vegetative Filter Adsorptive filter

26. Sediment Pond Baffle system Concrete Channel Surface Runoff Influent Sampling Point Charcoal/fiber filtersSediment Basin Vegetative Filter Storm Overflow Sediment Trap PAM Delivery Nursery Runoff Mitigation

27. PAM (Polyacrylamides)  Charged (anionic) linear chain polymer with a high molecular weight.  Granular, liquid, or tablet.  Reduces the movement of soil particles as well as associated chemicals (some pesticides and nutrients).  Charged (anionic) linear chain polymer with a high molecular weight.  Granular, liquid, or tablet.  Reduces the movement of soil particles as well as associated chemicals (some pesticides and nutrients).

29. No PAM Treatment PAM Treatment

30. Sediment Trap  Effective in slowing flow and dropping out sediment.  Easy to remove deposited sediment.  Most effective when flow is slow and slope is less than 5%.  Can be utilized when space is limited.  Effective in slowing flow and dropping out sediment.  Easy to remove deposited sediment.  Most effective when flow is slow and slope is less than 5%.  Can be utilized when space is limited.

32. Sediment Pond  Slows the movement of water entering channel.  Allows for the further settling of soil particles.  Temporary holding basin under low flow conditions.  Slows the movement of water entering channel.  Allows for the further settling of soil particles.  Temporary holding basin under low flow conditions.

34. Vegetative Filter  Traps sediment and reduces volume of runoff. Canna x ‘Tropicanna’ – propagation  Removes pesticides by trapping sediment as well as providing a beneficial environment for decomposition.  Most effective when flow rate is slow allowing for evapotranspiration to reduce overall flow.  Traps sediment and reduces volume of runoff. Canna x ‘Tropicanna’ – propagation  Removes pesticides by trapping sediment as well as providing a beneficial environment for decomposition.  Most effective when flow rate is slow allowing for evapotranspiration to reduce overall flow.

36. Suspended Solids in Runoff (mg/L) (May 2002) PondExitSediment trap Canna lilies strip

37. Bifenthrin in Runoff (ppb) (May 2002) Pond Exit Sediment trap Canna lilies strip 92%

38. Permethrin in Runoff (ppb) (May 2002) PondExitSediment trap Canna lilies strip 95%

39. Suspended Solids in runoff (mg/L) (June 2002) PondExitSediment trap Canna lilies strip

40. Bifenthrin in Runoff (ppb) (June 2002) Pond ExitSediment trap Canna lilies strip 91%

41. Permethrin in Runoff (ppb) (June 2002) PondExitSediment trap Canna lilies strip 100%

42. Adsorptive Filters  Physical filtration  Adsorptive removal  Feasibility?

43. Fiber/Activated Charcoal Filters

44. Effectiveness of Filters (1 day after) PondFilter #2TrapFilter #1

45. Effectiveness of Filters (1 week after) PondFilter #2TrapFilter #1

46. Review  Disadvantages Behavior unknown Behavior unknown Concentrated use Concentrated use Multiple pesticides with varying properties Multiple pesticides with varying properties  Disadvantages Behavior unknown Behavior unknown Concentrated use Concentrated use Multiple pesticides with varying properties Multiple pesticides with varying properties  Advantages Semi-point source “Mitigatable” (small) runoff Growers’ support  Advantages Semi-point source “Mitigatable” (small) runoff Growers’ support  What else?  Storm runoff conditions?  How clean is clean?  What else?  Storm runoff conditions?  How clean is clean?

47. California Department of Food & Agriculture California Department of Pesticide Regulation California SWRCB Santa Ana RWQCB El Modeno Gardens Nursery FMC Inc. UC Water Resources Center