Christine A. Waters, Henrieta Dulaiova, and Craig R. Glenn University of Hawai`i at Mānoa

1. Locating and Quantifying Coastal Groundwater Discharges Potentially Originating from a Wastewater Treatment Facility ***Provisional Data Release: Do Not Quote*** Christine A. Waters, Henrieta Dulaiova, and Craig R. Glenn University of Hawai`i at Mānoa WRRC Sustainability Issues on Tropical Islands Conference

2. Lahaina Wastewater Reclamation Facility (LWRF) Tracer Study Part of a Large Study funded by DOH and Army Corps of Engineers • Determine the time it takes for wastewater effluent from the LWRF to flow out to the ocean using dye tracer • Determine whether or not we can account for all of the injection waters using radon mass balance at sites being sampled for dye • Counsel local authorities on rates and magnitude of this discharge

3. The LWRF The County of Maui (to include Molokai, Lahaina, Kahului, and Kihei) creates an average excess of 11.4 million gallons of injection water per day (mgd). The LWRF creates an average excess of ~3-5 mgd Previous studies suggest this effluent is discharged to the ocean before it can be completely remediated naturally in the aquifer • Dailer et al., 2010 • Hunt and Rosa, 2009 • Atkinson et al., 2003 • Brown, 1995 • TetraTech, 1994

4. Importance Harmful Algal Blooms • Cladophora sericea • Hypnea musciformis Impact of Pharmaceuticals and Contaminants • Estrogens (Atkinson et al., 2002) • Fabric Brightener • Carbamazepine • Sulfamethoxazole Long-Term Sustainability of Recreation Waters Skippy Hau DLNR } (Hunt & Rosa, 2009) J.E. Smith

5. Honokowai Stream Former Pineapple Black Rock Former Sugarcane Golf Course and Resort Modified from Hunt and Rosa, 2009

6. Injection rates for lwrf during study periods June average injection: 3.24 mgd or 12,263 m3/d September average injection: 2.57 mgd or 9,727 m3/d

7. What Goes in Must Come Out! But do volumes of groundwater, comparable to injection volumes, escape from the studied seep locations? And where else might groundwater with effluent discharge?

8. Use of Radon as Geochemical Tracer • Naturally occurring • Conservative • Unique • Enriched in Groundwater Account for production and decay of Ra and Rn Radon is a gas, so some is lost to the atmosphere. Jbenthic + ʎIRa – Jatm - ʎIRn ± Jhor = 0 Groundwater Rn flux to overlying water column (assumes water is well-mixed) Loss by mixing Burnett and Dulaiova, 2003

9. C.A. Waters, 2010 Joseph Kennedy, 2011 Autonomous Radon Detector The “Little, Little Bad II” Meghan Dailer, 2011 Piezometer with Quick Connect

10. Meghan Dailer, 2011

11. ***Provisional Data Release: Do Not Quote***

12. Groundwater escaping from seeps during the month of September might NOT be inversely correlated with tides. ***Provisional Data Release: Do Not Quote***

13. How do our fluxes compare to injection volumes during the study periods? June average injection: 3.24 mgd or 12,263 m3/d September average injection: 2.57 mgd or 9,727 m3/d Recharge via precipitation to the watershed is ~132,489 m3/d

14. June average injection: 12,263 m3/d September average injection: 9,727 m3/d ***Provisional Data Release: Do Not Quote*** Flux per 100 m x 200 m Our fluxes (~12,000 m3/d) can account for most of the injection water in June and ALL of the injection water in September. However, our piezometer waters have a salinity of 3-4. So the water sampled must be a mixture of fresh (88% of total volume) and marine water (12%).

15. Honokowai Stream Seeps 2 and 3 Seep 1 Black Rock ***Provisional Data Release: Do Not Quote*** To Lahaina Town

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17. Acknowledgements Mahalo: • Joseph Fackrell • Joe Kennedy • Kim Mayfield • Bob Whittier • Meghan Dailer • Jacque Kelly • Skippy Hau • Roland Asakura • Maui DAR Hawaii Department of Health Army Corps of Engineers Photo by Joseph Kennedy, 2011

18. References • Atkinson, S., Atkinson, M.J., and Tarrant, A.M., 2003. Estrogens from sewage in coastal marine environments. Environmental Health Perspectives 111: 531-535. • Brown, K., 1995. An injection well effluent transport study, Maui, Hawaii. Master’s thesis for San Jose State University. • Burnett, W.C. and Dulaiova, H., 2003. Estimating the dynamics of groundwater input into the coastal zone via continuous radon-222 measurements. Journal of Environmental Radioactivity 69, 21-35. • Dailer, M.L., Knox, R.S., Smith, J.E., Napier, M., and Smith, C.M., 2010. Using δ15N values in algal tissue to map locations and potential sources of anthropogenic nutrient inputs on the island of Maui, Hawaii, USA. Marine Pollution Bulletin 60, 655-671. • Hunt, C.D. and Rosa, S.N., 2009. A multitracer approach to detecting wastewater plumes from municipal injection wells in nearshore marine waters at Kihei and Lahaina, Maui, Hawaii. USGS Scientific Invesitigations Report 2009-5253. • Shade, P., 1996. Water budget for the Lahaina District, Island of Maui, Hawaii. USGS Water-Resources Investigations Report 96-4238. • Tetra Tech, Inc., 1994. Effluent fate study, Lahaina Wastewater Reclamation Facility, Maui, Hawaii. Final Report Prepared for Hawaii State Department of Health. • County of Maui Wastewater Injection Wells. (n.d.). Retrieved November 6, 2011 from the County of Maui website: http://www.co.maui.hi.us/faq.aspx?TID=83 Photo by Joseph Kennedy, 2011

19. Questions? Photo by Joseph Kennedy, 2011

20. Salinity { ***Provisional Data Release: Do Not Quote***

21. Atkinson et al., 2003

22. Pre-Dye Injection Radon Survey Honokowai Stream Tide Level (m) Relative to MLLW Seeps 2 and 3 Seep 1 Black Rock To Lahaina Town

23. Post-Dye Injection Radon Survey Honokowai Stream Seeps 2 and 3 Tide Level (m) Relative to MLLW Seep 1 Black Rock To Lahaina Town