Solar Evaporation Ponds at the Salton Sea for Salinity Control

1. Solar Evaporation Ponds at the Salton Sea for Salinity Control Process, Progress, and Opportunities

2. Agrarian Research and Management Company under contract to

3. Solar Evaporation Ponds offer a salinity control method that is: • Technically feasible • Economically viable • Environmentally friendly

4. Existing solar salt ponds in operation for over 100 years

5. Evaluation of suitable area for siting of solar evaporation ponds at the Salton Sea based on soil seepage, slope, and considerations of land use

6. Large ponds take in brine and expose it to sunlight and evaporation

7. The evaporation ponds concentrate salt and evaporate water until only solid and bittern salts remain Water volume Water from Salton Sea Concentration Concentrator Pond 1 Concentrator Pond 2 Concentrator Pond 3 Solid Salt Pond Bittern salts

8. Pumps and gravity move the water

9. Pilot Demonstration Project at Niland

10. How Evaporation Ponds can Control Salinity at the Salton Sea Inflow to Sea: water + salt No outflow: salt accumulates Salton Sea Water + salt removed to evaporation ponds: Water evaporates Salt remains on shore

11. Possible Conceptual Design for Solar Evaporation Ponds

12. Salt is stored where it is deposited, and the pond levees are built higher to accommodate it

13. Bittern salts may not be solid, but they make up a very small volume Bittern ponds

14. Progress at the Pilot Pond Project Evaporation rates of brine

15. Salt formation in the crystallizer ponds

16. Collection of brine and salt chemistry data

17. Evaluation of seepage through berms as well as floor of ponds

18. Solar Salt Ponds and Wildlife

19. Wildlife Refuges in Salt Pond Habitat San Diego National Wildlife Refuge with Western Salt Don Edwards NWF San Francisco Bay with Cargill Salt CDF&G Wildlife Refuge Napa, State management alone

20. shallow saline water for feeding

21. saline water produces rich food source

22. nesting habitat

23. Berms and islands create safe resting places

24. Crystallizers are a refuge for resting

25. Lands affected would be adjacent to, or close to, the existing Sea margins

26. Potential accumulation of contaminants in concentrators and solid salt deposits • Selenium • Pesticides • Metal residues • Other agricultural chemicals such as fertilizers Preliminary indications are that these issues will not prove to be problems for solar evaporation pond implementation

27. Advantages and Benefits • Solar ponds most economical • Solar salt ponds in use for over 100 years • Solar salt ponds can be managed for habitat • “Win – Win” situation for salinity control and habitat • Alternatives available to deal with loss of water in the Sea • Economic and environmental benefits to area

28. Future of Solar Evaporation Salt Ponds at the Salton Sea • Salinity problem must be addressed in order to maintain habitat values • Assessment of environmental concerns is in progress The most viable and beneficial solution available to solve the salinity problem

30. Salts produced from a typical brine CaSo4 Ton NaCl / ac/in NaCl MgCl NaSO4 KCl

31. Results from the brine chemistry investigations