1. Fate and Water Impacts of Produced Water Operations at OSPER Sites, Osage County, OK: Major (Unresolved?) Issues Yousif Kharaka, James Thordsen, Evangelos Kakouros William Herkelrath, and Marvin Abbott* U. S. Geological Survey, Menlo Park, CA 94025; *Oklahoma City, OK 73116 IPEC-13, San Antonio, TX November 17-20, 2006 Financial support from DOE-NETL Drilling support from EPA-NRMRL Osage Nation Tribal Authorities U.S. Army Corps of Engineers

2. Multidisciplinary Investigation of Field Sites Impacted by Petroleum Production  Goal: Conduct research to investigate the distribution, fate and Impact of contaminants released as a result of petroleum production.  Contaminants include salts, trace metals, hydrocarbons and Naturally occurring radioactive material (NORMs).  Impacts cover those affecting soil, surface and ground water and the local ecosystem.

3. Distribution of Petroleum wells in Oklahoma, Osage County, & the study Area

4. Topics Discussed 1- OSPER ‘A’ & ‘B’ sites, Osage County, OK. 2- Chemical & isotopic compositions of source & ground waters at OSPER ‘A’ & ‘B’ sites. 3- Delineating the plume boundaries at OSPER ‘B’. 4- What are the major (unresolved?) issues? 5- Future plans & concluding remarks.

5. Major (Unresolved?) Issues 1)- What are the distinguishing chemical and isotopic markers of uncontaminated local groundwater and produced water? 2)- What are the water-mineral-bacterial interactions that lead to very high sulfate (>5,000 mg/L) concentrations in contaminated groundwater? 3)- How does the brine flow through relatively thick (2-7 m) shale and siltstone beds? 4)- How much salt is removed by surface runoff and other natural processes?

7. Sampling Trips to the Sites March 2001--- Source fluids from oil wells, GW, and Skiatook Reservoir. Surface pools at both sites. February 2002 --- ~60 Geoprobe, auger and rotary wells drilled, cored, completed and sampled at and two sites. June 2002 --- Water level, conductance, and T measurements, followed by collection of ~40 water and a few oil samples. November 02 --- Drilling with geoprobe and sampling. March-April 03 ---Drilling (EPA auger) and sampling. January 2004 --- (9) deep wells (WRD air) at “A”, and sampling. May 2004 --- (4) deep (EPA auger) wells at “B”; sampling. February 2005 --- Water levels and sampling at both sites. September 2005 --- Weir discharges. March 2006 --- Weir discharges.

9. Organics in Produced Water (mg/L) DOC Mean Produced Water 5-1000 Surface Water 7 Ground Water 0.7 ACETATE & OTHER ACID ANIONS BTEX PAHs PHENOL 10,000 60 10 20 4 – METHYL PHENOL 2 BENZOIC ACID 5 4 – METHYL BENZOIC ACID 4 2 – HYROXY BENZOIC ACID 0.2 3 – HYDROXY BENZOIC ACID 1.2 Kharaka and Hanor, 2004

10. Selected Wells (a)- BA-01s (b)- BE-17 (c)- BR-01d

11. OSPER “B” Site; Traverse A-A`

12. OSPER “B” Site; Traverse D-D`

15. Double-layer Clay Membrane

16. Mineral-Water Interactions for S at OSPERs

18. Summary and Conclusions  Significant amounts of produced water, but minor amounts of oil and organics, have and continue to be released to ground surface from the brine pits and flow towards the Skiatook Reservoir.  Three GW plumes ( up to 30,000 mg/l TDS) extend from brine pits & intersect Skiatook reservoir. High SO 4 is from oxidation of pyrite.  Physico-chemical interactions of brine and clay allow brine (plume) penetration through 2-7 m shale & siltstone beds.  Remediation will not be successful without first blocking produced water releases from the brine pits and other sources.

20. OSPERs Project Investigators USGS-WRD –Yousif Kharaka and staff- inorganic & organic aqueous geochemistry –Bill Herkelrath and staff- hydrology and modeling –Mike Godsy (Ean Warren)- microbial ecology, microbiogeochemistry –Tom Yanosky- tree ring geochemistry –Fran Hostetler- organic geochemistry –Marvin Abbott- site manager, GPS, GIS USGS-GD –Jim Otton- geology and project management –Bob Zielinksi- inorganic solid geochemistry, biogeochemistry –Cyndi Rice- inorganic solid geochemistry, CEC –Jim Cathcart- soil and bedrock mineralogy –Bruce Smith and others- geophysics USGS-BRD –Bob Keeland-oak-tree ecology and tree-ring chronology OSU –Joe Bidwell- lacustrine invertebrate ecology and toxicology USEPA- Ada Research Lab –Don Kampbell and contractors- site characterization/reclamation, – Geoprobe support

21. Importance of Protecting Ground Water 50% of drinking water in USA is from GW 95% of rural America is dependant on GW 21% of water withdrawals in USA are GW GW use increased from 13 x 10 10 L/day in 1950 to 33 x 10 10 L/day in 2000 Once GW is contaminated, remediation is very costly or impossible

22. Primitive model assumptions – model set up and initial conditions Uniform sandstone formation ~ 30 meters thick Sandstone hydraulic conductivity = 1 cm/day Sandstone porosity = 0.10 Recharge is steady at 1 cm/year Water table parallel to sloping ground surface at a depth of 5 meters Lateral head gradient is ~ 0.035 m/m Longitudinal dispersion = 1.0 m, lateral dispersion 10.0 cm