1. Carmichael Town Hall Meeting Western Groundwater Operable Unit - Update 12 March 2008 Alexander MacDonald (RWQCB) 916-464-4625 amacdonald@waterboards.ca.gov

2. Outline Background and Regulatory Perspective 2004 Plume in Carmichael Contaminant Plumes in 2008 Work Completed Since 2004 The Big Picture

3. Aerojet Interstate 80 US 50 Sunrise Boulevard American River Sacramento Interstate 99

4. Background Aerojet - Superfund Cleanup Site -1982 Oversight Provided by State and USEPA Past Operations Led to Soil and Groundwater Pollution Primary Focus – Off-site Groundwater Western Groundwater Operable Unit

5. Aerojet IRCTS Western Groundwater Operable Unit Area 4 Area 3 Area 1 Area 2 N

6. Contaminants of Concern Solvents - TCE, PCE, Freon, Chloroform Perchlorate – component of solid rocket propellant N-nitrosodimethyhylamine (NDMA) – associated with liquid rocket fuel

7. NDMA Found in Hydrazine-Based Rocket Fuel Found in hotdogs, smoked/cured meats, malted beverages, and tobacco Public Health Goal is 3 ppt (Dec 06) No Drinking Water Standard DHS Notification Level is 10 ppt

8. Carmichael Water District Drinking Water Wells Arden-Cordova Water Service Wells Existing Monitor Wells Proposed Monitor Wells Groundwater Flow Direction ND 93 270 300 50 34 51 ND 6 7 2004 NDMA Plume

9. What Has Been Done in Area 4 Additional Groundwater Monitor and Extraction Wells Built Construction and Operation of the GET L-B Facility on Bajamont - 2007 Negotiated Agreement with Sacramento County to Allow Construction GET L in Ancil Hoffman Park – begin construction in Summer 2008 Treated water to be used on the golf course Modifed Aerojet’s Permit to Discharge Treated Water to the American River CEQA Completed

10. Carmichael Water District Wells Changes Since June 04 Groundwater Flow Direction GET L-B Operating New Extraction Wells Ancil Hoffman Park New Monitoring Wells

11. ND 78 ND 180 Carmichael Water District Wells Arden-Cordova Water Service Wells Monitor Wells ND 39 1.8J 42 430 ND NDMA Layer C Groundwater Flow Direction 67 2J 36 ND

12. 98 250 350 ND Carmichael Water District Wells Monitor Wells ND 39 ND NDMA Layer D Groundwater Flow Direction ND Arden-Cordova Water Service Wells ND 78 1.4J ND

13. 4.7 Carmichael Water District Wells Monitor Wells ND 3.3J 4.5 7.8 Perchlorate Layer C Groundwater Flow Direction 1.9J ND Arden-Cordova Water Service Wells 2.0J 1.8

14. 1.4J 4.6 5.9 ND 2.2J Carmichael Water District Wells Monitor Wells ND Perchlorate Layer D Groundwater Flow Direction ND Arden-Cordova Water Service Wells ND 6.7

15. Next Steps Complete Construction of GET L-A - 2009 Complete Construction of GET K – 2008/9 Operate Systems and Evaluate Capture – modify systems as needed Treatment Facilities Designed to Allow for Expansion

16. Carmichael Water District Wells Next Steps GET L-A GET KA Ancil Hoffman Park Potential Extraction Well GET L-B DONE

17. N Area for new extraction wells Current flow 13,000 gpm 86 billion gallons treated to date Estimated Future Flow – 20,000 gpm 150 lbs chemicals removed daily Over 720,000 lbs removed to date Future Extraction Locations

18. N GET L-A/L-B GET K GET HA GET E/F GET J ARGET GET D Future GET E/F Expansion Alpha GET (Boeing) Admin GET (Boeing) GET A GET B Future GET A Expansion WRND GET HB (Boeing & AGC) Aerojet Plume Capture

19. N Soil Portions of Operable Units Carve-out Land OU-5 – Perimeter Groundwater Boundary OU Central OU Cavitt Ranch Island OU Eastern OU

20. Questions