1. 1 Groundwater / Aquifer Remediation State Water Plan Update State Water Plan Update 77th Advisory Committee Meeting 30 January 2004

2. 2 Groundwater Remediation Generally pertains to “pump and treat” systems Generally pertains to “pump and treat” systems Groundwater is pumped to the surface and processed by some technique that removes the contaminant Groundwater is pumped to the surface and processed by some technique that removes the contaminant Recharge and movement of water thru the aquifer will also remediate the aquifer over time Recharge and movement of water thru the aquifer will also remediate the aquifer over time Treated water can then be re-used or disposed of Treated water can then be re-used or disposed of

3. 3 Pump and Treat Activated alumina Activated alumina Biological Biological Blending Blending Coagulation/filtration Coagulation/filtration Granular activated carbon; GAC Granular activated carbon; GAC Ion exchange; IX Ion exchange; IX Lime softening Lime softening Packed tower aeration; air stripping Packed tower aeration; air stripping Reverse osmosis; RO Reverse osmosis; RO Ultra-violet photoionization Ultra-violet photoionization

4. 4 Aquifer Remediation Generally pertains to “in situ” treatment systems Generally pertains to “in situ” treatment systems Treatment is by physical, chemical, biological, or electrokinetic methods Treatment is by physical, chemical, biological, or electrokinetic methods

5. 5 In-situ Air sparging Air sparging Bio-sparging Bio-sparging Bio-venting Bio-venting Cosolvents Cosolvents Electrokinetics Electrokinetics Electron acceptors; NO 3, SO 4,Fe +3 Electron acceptors; NO 3, SO 4,Fe +3 Electron donors; chlorinated hydrocarbons Electron donors; chlorinated hydrocarbons Fluid cycling Fluid cycling Hydro or pneumatic fracturing Hydro or pneumatic fracturing Soil vapor extraction; SVE Soil vapor extraction; SVE Surfactant enhancements Surfactant enhancements Thermal enhancements Thermal enhancements Treatment walls Treatment walls Vitrification Vitrification

6. 6 Desalination The removal of salt, especially from seawater, but also from brackish water starting at about 900 ppm total dissolved solids The removal of salt, especially from seawater, but also from brackish water starting at about 900 ppm total dissolved solids May include removal of trihalomethanes, nitrate, and hardness May include removal of trihalomethanes, nitrate, and hardness

7. 7 What is a salt? Sodium chloride, NaCl, or table salt, is an example of a salt. A salt is any compound that readily dissolves in water. Salts are formed by the combination of any negative ion, except hydroxide, with any positive ion, except hydrogen or hydronium. They can also be the water soluble precipitate produced as the result of neutralization of an acid with a base. Common salts in California groundwater include sodium chloride, sodium sulfate, potassium chloride, calcium sulfate, magnesium sulfate, magnesium chloride, calcium chloride, and sodium and calcium carbonate and bicarbonate. Sodium chloride, NaCl, or table salt, is an example of a salt. A salt is any compound that readily dissolves in water. Salts are formed by the combination of any negative ion, except hydroxide, with any positive ion, except hydrogen or hydronium. They can also be the water soluble precipitate produced as the result of neutralization of an acid with a base. Common salts in California groundwater include sodium chloride, sodium sulfate, potassium chloride, calcium sulfate, magnesium sulfate, magnesium chloride, calcium chloride, and sodium and calcium carbonate and bicarbonate.

8. 8 Desalination vs. remediation Desalination and remediation in their ‘purest’ forms are separate issues Desalination and remediation in their ‘purest’ forms are separate issues Today there is overlap depending on the constituent of interest & the method used to remove that constituent Today there is overlap depending on the constituent of interest & the method used to remove that constituent Membranes and nanofiltration previously used in desal are more frequently being used in remediation Membranes and nanofiltration previously used in desal are more frequently being used in remediation

9. 9

10. 10 Remediation sites Some type of treatment has taken place, or is taking place at about 18,500 sites in California Some type of treatment has taken place, or is taking place at about 18,500 sites in California Treatment is also taking place at thousands of drinking water sources Treatment is also taking place at thousands of drinking water sources Records of these projects are on file in offices of the Regional Water Quality Control Boards, Department of Health Services Districts, Department of Toxic Substances Control, & local agencies Records of these projects are on file in offices of the Regional Water Quality Control Boards, Department of Health Services Districts, Department of Toxic Substances Control, & local agencies The records have not been compiled in a statewide summary The records have not been compiled in a statewide summary

11. 11 Contaminants--1 1,2-Dibromo-3-chloropropane, DBCP 1,2-Dibromo-3-chloropropane, DBCP 1,2-Dichloroethane 1,2-Dichloroethane 1,2,3-Trichloropropane, 1,2,3-TCP 1,2,3-Trichloropropane, 1,2,3-TCP Arsenic, As Arsenic, As Carbon tetrachloride, CTC Carbon tetrachloride, CTC Ethylene dibromide, EDB Ethylene dibromide, EDB Methyl tertiary butyl ether, MTBE Methyl tertiary butyl ether, MTBE N-Nitrosodimethylamine, NDMA N-Nitrosodimethylamine, NDMA

12. 12 Contaminants--2 Nitrate as NO 3 - Nitrate as NO 3 - Nitrate + Nitrite (NO 2 ) as N Nitrate + Nitrite (NO 2 ) as N Perchlorate, ClO 4 Perchlorate, ClO 4 Tetrachloroethylene, PCE Tetrachloroethylene, PCE Total petroleum hydrocarbons, TPH Total petroleum hydrocarbons, TPH Trichloroethylene, TCE Trichloroethylene, TCE Uranium, U Uranium, U

13. 13 Total petroleum hydrocarbons Describes a large family of several hundred chemical compounds derived from crude oil Describes a large family of several hundred chemical compounds derived from crude oil Examples are hexane, jet fuels, mineral oils, benzene, toluene, xylenes, naphthalene, fluorene, petroleum products, gasoline Examples are hexane, jet fuels, mineral oils, benzene, toluene, xylenes, naphthalene, fluorene, petroleum products, gasoline Not practical to measure for each chemical Not practical to measure for each chemical Thus, TPH is measured Thus, TPH is measured

14. 14 Potential costs with remediation Characterizing the aquifer or groundwater in terms of all the contaminants present Characterizing the aquifer or groundwater in terms of all the contaminants present Capital cost of the remediation system Capital cost of the remediation system Operation & maintenance costs during the life of the project Operation & maintenance costs during the life of the project Operation of the system may be required for many years Operation of the system may be required for many years

15. 15 Potential costs without remediation Securing an alternative water supply Securing an alternative water supply Long-term foregone profits and taxes Long-term foregone profits and taxes Foregone housing development because there is inadequate water Foregone housing development because there is inadequate water Continued spreading of the contaminant, making eventual remediation more costly Continued spreading of the contaminant, making eventual remediation more costly

16. 16 Major issues—water quality Contaminant source must be eliminated Contaminant source must be eliminated Constituent and concentration vary Constituent and concentration vary Some constituents may be unregulated Some constituents may be unregulated Contamination may be poorly characterized Contamination may be poorly characterized Locating plume dimension is costly Locating plume dimension is costly Program design requires these data Program design requires these data Additional contaminants may be found Additional contaminants may be found

17. 17 Major issues—water quantity Aquifer geometry and characteristics must be known Aquifer geometry and characteristics must be known Water budget should be developed Water budget should be developed

18. 18 Major issues—local government & land use Local government and local agencies should: Local government and local agencies should: Limit potentially contaminating activities in recharge areas Limit potentially contaminating activities in recharge areas Work together to develop and maintain a good quality long-term water supply for beneficial uses Work together to develop and maintain a good quality long-term water supply for beneficial uses

19. 19 Major issues—costs of treatment Who are the responsible parties? Who are the responsible parties? How quickly can they be identified? How quickly can they be identified? Who will pay? Who will pay? What is the appropriate share for each responsible party? What is the appropriate share for each responsible party?

20. 20 Major issues—potential impacts Remediation may increase the available water supply Remediation may increase the available water supply Aquifer remediation may increase the amount of storage capacity that is available for use without treatment, thereby lowering costs Aquifer remediation may increase the amount of storage capacity that is available for use without treatment, thereby lowering costs

21. 21 Recommendations--1 Provide funding to local agencies for remediation projects Provide funding to local agencies for remediation projects Identification of responsible parties Identification of responsible parties Capital costs Capital costs Identify responsible parties more quickly so funding is available sooner Identify responsible parties more quickly so funding is available sooner Provide technical assistance Provide technical assistance

22. 22Recommendations--2 Compile information on current projects Compile information on current projects Contaminants involved Contaminants involved Amount of contaminant Amount of contaminant Type of treatment Type of treatment Projected life of the project Projected life of the project Capital cost Capital cost O & M cost, including waste disposal O & M cost, including waste disposal Amount of groundwater treated Amount of groundwater treated Seasonal changes in amount treated Seasonal changes in amount treated Extraction wells Extraction wells Number of connections served Number of connections served

23. 23 Recommendations--3 The 3 P rule for protecting groundwater is: PREVENT, PREVENT, PREVENT groundwater contamination The 3 P rule for protecting groundwater is: PREVENT, PREVENT, PREVENT groundwater contamination Local agencies should implement source water protection programs based on the assessments completed in 2003 Local agencies should implement source water protection programs based on the assessments completed in 2003 A lot more education is needed!!! A lot more education is needed!!!