January Meeting at Orange County Water District, Fountain Valley
Register Here for January Meeting
Date: January 27th, 2020
Please join South Coast Geological Society for our monthly meeting on Monday, January 27th, 2020 from 6PM to 8PM at the Orange County Water District (18700 Ward Street, Fountain Valley, CA 92708). We are hosting Jason Dadakis, P.G., C.HG, Executive Director of Water Quality & Technical Resources who will present their topic on PFOS/PFAS.
Speaker: Jason Dadakis, P.G., C.HG, Executive Director of Water Quality & Technical Resources
Talk Title: PFAS in the Orange County Groundwater Basin: Occurrence, Regulation, and Impacts on Local Water Supply
Abstract: Per- and polyfluoroalkyl substances (PFAS) represent a large group of manmade chemicals originally developed in the 1940s. PFAS possess number of unique properties, including oil- and water resistance, resistance to degradation (due to their strong carbon-fluorine bonds), and surfactant-like characteristics. As such, PFAS have been manufactured for use in a wide variety of industrial and consumer applications. Two individual “long-chain” PFAS, perfluorooctanoic acid (PFOA) and perfluorooctane sulfonate (PFOS), have been phased out of USA and EU production due to concerns about their effects on human health and the environment. The widespread use of PFAS, both long-chain “legacy” compounds and newer “short-chain” replacements, coupled with their persistence has resulted in worldwide environmental occurrence in air, soil, and water. In the Orange County groundwater basin, the presence of PFAS was first documented by the Orange County Water District (OCWD) during the 2013-2015 federal Environmental Protection Agency (EPA) Unregulated Contaminant Monitoring Rule 3 (UCMR3) program. Subsequent testing by OCWD has helped define the extent of PFAS-impacted groundwater in the northcentral portion of the basin, likely reflective of the historical recharge of PFAS-impacted Santa Ana River surface water. Former and active military airfields in basin also represent sources of PFAS, due to these facilities’ use of aqueous film-forming foams (AFFF) to train for and fight Class B hydrocarbon fires. As the state of California continues to establish advisory drinking water guidelines (i.e., Notification and Response Levels) and to begin the development of enforceable standards (i.e., Maximum Contaminant Levels), OCWD is conducting both pilot wellhead treatment and engineering planning studies in support of local retail water agencies with PFAS-impacted groundwater supplies.
Jason Dadakis is the Executive Director of Water Quality and Technical Resources for Orange County Water District (OCWD) in Fountain Valley, California. There he oversees water quality monitoring, laboratory analysis, regulatory compliance, external independent review, and applied research in support of OCWD’s groundwater management activities and recycled water projects, including the Groundwater Replenishment System. Currently, he is the lead facililtator of a PFAS Workgroup comprised of local retail water agencies. Jason is a registered Professional Geologist (P.G.) and Certified Hydrogeologist (C.HG) in the State of California. He holds a B.A. in Earth Sciences from Dartmouth College and an M.S. in Hydrology from the University of Arizona.
1U.S. Geological survey, California Water Science Center, 6000 J St., Sacramento, CA 95819
2U.S. Geological Survey, 4165 Spruance Rd., San Diego, CA 92101
3Crustal Geophysics and Geochemistry Science Center, U.S. Geological Survey, Denver, CO 80225
Increased oil and gas production in many areas has led to concerns over the effects these activities may be having on nearby groundwater quality. In this study we determine the lateral and vertical extent of groundwater with less than 10,000 mg/l TDS near the Lost Hills-Belridge oilfields in northwestern Kern County, California and document evidence of impacts by produced water disposal within the Tulare aquifer and overlying alluvium—the primary protected aquifers in the area.
The depth at which groundwater salinity surpasses 10,000 mg/l ranges from 150 m (500 ft) in the northwestern part of the study area to 490 to 550 m (1600-1800 ft) in the south and east respectively as determined by geophysical log analysis and lab analysis of produced water samples. Comparison of logs from replacement wells with those of their older counterparts shows relatively higher resistivity intervals representing the vadose zone or fresher groundwater being replaced by intervals with much lower resistivity due to infiltration of brines from surface disposal ponds and injection of brines into disposal wells. The effect of the surface ponds is confined to the alluvial aquifer—the underlying Tulare aquifer is largely protected by a regional clay layer at the base of the alluvium. Sand layers affected by injection of produced waters in nearby disposal wells often exhibit log resistivity profiles that change from high resistivity in their upper parts to low resistivity near the base due to gravity segregation of the denser brines within each sand.
Jan Gillespie received her B.S. degree in geology from Bemidji State University, her M.S. from South Dakota School of Mines and Technology, and her Ph.D. from the University of Wyoming. Formerly a petroleum and hydrogeology professor in the Department of Geosciences at California State University, Bakersfield, and a petroleum geologist in the San Joaquin Valley of California, she is now a research scientist for the US Geological Survey’s regional aquifer monitoring project for California SB4 (the Well Stimulation Bill) delineating protected aquifers near oil producing areas.
His interest in geology came at a young age growing up in the Transverse Ranges of southern California. His geologist father, Eric Lindvall, helped instill an appreciation of the outdoors (and therefore geology) and was later instrumental in shaping Scott’s career. His interest in earthquakes was triggered at nine years old in the early morning hours of February 7, 1971 with the M6.6 San Fernando earthquake. Experiencing strong ground shaking from the main shock and several large aftershocks in the epicentral region, while dust was slowly rising from rock falls in the surrounding canyons, left a lasting impression.
Scott has performed detailed mapping of surface ruptures of earthquakes in southern California and Turkey, including the 1986 M6.6 Superstition Hills, 1992 M7.3 Landers, 1999 M7.4 İzmit (Kocaeli), 1999 M7.1 Düzce, and the 1999 M7.1 Hector Mine earthquake ruptures. Scott’s experience in neotectonics, paleoseismology, and geomorphology has enabled him to pursue research projects designed to better quantify the timing of past events, slip rate, surface displacement, and style of deformation on active strike-slip and reverse faults throughout southern California. He has been awarded over a dozen research grants funded by the U.S. Geological Survey National Earthquake Hazards Reduction Program (NEHRP) and the Southern California Earthquake Center (SCEC). These studies include paleoseismic investigations of the Sierra Madre, Hollywood, Simi, Red Mountain, and San Andreas faults in Los Angeles and the Transverse Ranges, the Rose Canyon fault in San Diego, and the numerous faults in the Eastern California Shear Zone that ruptured in the 1992 Landers and 1999 Hector Mine earthquakes.
Scott has directed geologic evaluations and seismic source characterizations in a variety of tectonic environments ranging from active plate boundaries to stable cratons. He served on the Technical Integration Team for a multi-year study sponsored by the US Nuclear Regulatory Commission, US Department of Energy, and the Electric Power Research Institute to develop the Central and Eastern United States Seismic Source Characterization for Nuclear Facilities, which has served as the regional seismic source model for hazard evaluations of nuclear facilities since its publication in 2012. Scott has also served on the advisory committee of the Earthquake-Induced Landslides Working Group for the California Geological Survey’s (CGS) Seismic Hazards Mapping Program and, more recently, the CGS Special Publication 42 Advisory Panel to update the regulatory guidance on assessing fault rupture hazards in California.
Details: Join the South Coast Geological Society for a night of fun, cheer, and great company as we host our Annual Holiday Party and Benefit night this year! Proceeds from this night will go to support us and our mission of promoting geological education and support for geoscientists. So help us make our New Year great by celebrating with SCGS!