NORTHWEST ST PI PICEANCE CREEK BASI SIN HYDROGEOLOGY Colorado - PowerPoint PPT Presentation

NORTHWEST ST PI PICEANCE CREEK BASI SIN HYDROGEOLOGY Colorado School of Mines Colorado Energy Research Institute 30th Oil Shale Symposium October 18-22, 2010 Michael Day 2 , Erik Hansen 1 , Terry Gulliver 2 , Bill Mckinzie 3 1 – Shell Exploration & Production Co.; 2 – Norwest Corp.; 3 – Retired Shell Exploration & Production Co. copyrig ight 2010, Sh Shell ll Explo loratio ion and Pr Productio ion Co., and it its affi filia liates

Introduction Historical Background n Piceance Creek Basin (PCB) hydrogeology studied previously n Emphasis starting in late 1960 ’ s and early 1970 ’ s n Groundwater plays a vital role in oil shale development n Mining, in situ retorting, in situ conversion (ICP) thermal n Shell has installed >300 wells, obtained ~80 cores, taken >5,000 water level measurements, obtained >8,000 analytical samples, conducted >1,000 packer permeability tests, performed >300 pumping stress tests, and developed a PCB regional numerical flow and transport model and numerous project-specific, local models n Starting with SIFT near Piceance Creek and Horse Draw mine (70 ’ s) n Red Pinnacle (southern rim) 80 ’ s n Shell Mahogany fee property pilots, MFE, MDP Original, Deep Heater Test, MDP South (90 ’ s – 2007), MIT ( ‘ 04- ’ 05,) FWT ( ’ 05 – present) n Federal PLA/RD&D and surrounding area (2000 – present) Results of Shell Investigations (this presentation) n Discussion of data gathered from hydraulic testing, geochemistry and isotopes n Designation of hydrostratigraphy n Development of numerical flow and transport model copyrig ight 2010, Sh Shell ll Explo loratio ion and Pr Productio ion Co., and it its affi filia liates 2 October r 20, 2010

Shell and Other Hydrology Wells in the Piceance Creek Basin copyrig ight 2010, Sh Shell ll Explo loratio ion and Pr Productio ion Co., and it its affi filia liates 3 October r 20, 2010

Shell and Other Hydrology Wells in Fee and PLA Areas copyrig ight 2010, Sh Shell ll Explo loratio ion and Pr Productio ion Co., and it its affi filia liates 4 October r 20, 2010

Piceance Creek Basin Topography & Features Yellow Creek White River Cross- Section Location General upper GW flow direction (L7/ L6/L5) Shell Elevation, ft msl North PLA C-a Tract FWT Piceance Creek Yellow MIT Creek PLA Shell East PLA MDP Faulting (feet) copyrig ight 2010, Sh Shell ll Explo loratio ion and Pr Productio ion Co., and it its affi filia liates 5 October r 20, 2010

USGS Work N. Piceance Basin Plan View Up Flow lower aquifer to upper Extend of Faults / Fracturing aquifer – model output Water generally flows from the edge of the basin to the creek drainages Fig igures from: m: Robson, S. S. G.; Sa Sauln lnie ier, G. J., Jr.; 1981 Hydrogeochemis mistry and simu imula lated solu lute trans tr nspor ort, t, Pic Picea eanc nce Ba Basin, in, nor northw hwes ester ern Color olorado USG SGS S Pr Professio ional l Paper r 1196 copyrig ight 2010, Sh Shell ll Explo loratio ion and Pr Productio ion Co., and it its affi filia liates 6 October r 20, 2010

Basin Litho-Stratigraphy & USGS Hydrology Units R7 Mahogany (thought by USGS to be a very good “ seal ” ) separates Upper from Lower Aquifer n Units Heads and geochemistry support a different division discussed later n 9000 Shell Fee MDP MIT 8000 Federal RD&Ds, C-a Tract PLAs 7000 Topo White River Piceance Creek Elevation (AMSL) R7 6000 R5 Upper Aquifer Unit L2 ? (Uinta and A-G) Nahc 5000 Lower Aquifer Unit (B-G -> L3) Faults Known Saline Zone (nahcolite) 4000 No Flow Potential 3000 0 5 10 15 20 25 30 Distance (Miles) copyrig ight 2010, Sh Shell ll Explo loratio ion and Pr Productio ion Co., and it its affi filia liates 7 October r 20, 2010

Summary of Shell Baseline Characterization Tests and Measurements Core holes ¡ 80 ¡ Groundwater monitoring wells ¡ 348 bedrock wells (cased to top & drilled out to base of open interval) ¡ Alluvial monitoring wells ¡ 13 ¡ Single well pumping tests ¡ 300, ~ 6-8-hour ¡ Multi well pumping test ¡ 27 tests over 3 sites, up to 72 hr ¡ Multi packer slug tests ¡ 1,087, mostly 10 and 20 ft intervals ¡ XD4 XD4 Injection fall-off tests w/ packers ¡ 61 ¡ Packer r 4 Water Level measurements ¡ 5,862 ¡ Bedrock water quality analyses ¡ 8,680 (minimum 5 quarters / well) ¡ 10 10 ’ XD3 XD3 Alluvial water quality analyses ¡ 149 (up to 5 quarters / well) ¡ Packer r 3 XD2 XD2 10 10 ’ Test Te Zo Zone Packer r assemb mbly Packer r 2 XD1 XD1 10 ’ 10 Packer r 1 copyrig ight 2010, Sh Shell ll Explo loratio ion and Pr Productio ion Co., and it its affi filia liates 8 October r 20, 2010

Rich and Lean Oil Shale n Lean, highly fractured oil shale results in saturated water bearing interval or aquifer n Nahcolite dissolution also results in L4 and L3 water bearing intervals n Rich, less fractured oil shale results in aquitard or “ seal ” – Generally, but is variable relative to the up-scaled R & L zones and will include exceptions . . . Lean, Fracture Oil Shale => Water Bearing Intervals ??? Rich, Less Fracture Oil Shale => “ Seals ” ??? ~5 ft ~5 f copyrig ight 2010, Sh Shell ll Explo loratio ion and Pr Productio ion Co., and it its affi filia liates 9 October r 20, 2010

Hydraulic Conductivities of WBIs n Approximate log-normal transmissivities n L3 distribution reflects nahcolite presence or dissolution Log Transmissivity, L 2 /T UT L7 BG L5 L4 L3 nahcolite largely ¡not ¡dissolved 0 20 40 60 80 100 Cumulative % < copyrig ight 2010, Sh Shell ll Explo loratio ion and Pr Productio ion Co., and it its affi filia liates 10 10 October r 20, 2010

Geochemistry of the WBIs 1,000,000 600 UT L7 Sulfate, mg/L L6 400 Na, mg/L L5 10,000 L4 L3 200 100 0 0 50 100 150 200 250 10 100 1,000 10,000 100,000 Alkalinity (as CaCO3) mg/L Ca + Mg, mg/L n L3 and L4 have very low Ca & Mg with a spread of Na; low sulfate; spread in alkalinity n UT, L7, L6 and L5 (and AL) have low Na and spread of Ca & Mg; large spread in sulfate; similar alkalinity (L5 is somewhat transitional) copyrig ight 2010, Sh Shell ll Explo loratio ion and Pr Productio ion Co., and it its affi filia liates 11 11 October r 20, 2010

Shell Piceance Creek Basin Hydrogeology Shell separates upper from lower at the R5 Seal copyrig ight 2010, Sh Shell ll Explo loratio ion and Pr Productio ion Co., and it its affi filia liates 12 12 October r 20, 2010

Shell PCB Hydrogeology Cross-Section (location above) n Uinta, upper Parachute Ck, and lower Parachute Ck are major WBIs 9000 Shell Fee MDP MIT 8000 Federal RD&Ds, C-a Tract PLAs 7000 Topo White River Piceance Creek Elevation (AMSL) R7 6000 R5 R8 R7 L2 L7 R6 Uinta WBIs ? L6 R5 Nahc L5 5000 Upper Parachute Creek WBIs R4 Lower Parachute Creek WBIs L4 ? L3 Faults ? Known Saline Zone (nahcolite) 4000 No Flow Potential 3000 0 5 10 15 20 25 30 Distance (Miles) copyrig ight 2010, Sh Shell ll Explo loratio ion and Pr Productio ion Co., and it its affi filia liates 13 13 October r 20, 2010

Numerical Flow Model Domain n About 600 square miles n Rotated to align with major and Model l doma main in and minor anisotropic rotatio ion hydraulic conductivity seen in some layers n Natural no-flow or general head boundaries copyrig ight 2010, Sh Shell ll Explo loratio ion and Pr Productio ion Co., and it its affi filia liates 14 14 October r 20, 2010

Boundary Conditions and Water Balance Boundary Condit itio ions Water r Bala lance n 567,600 acres of N. Piceance Creek drainage basin n Base flow recharge calculation (Dec – Feb) n Recharge = Discharge (Stream Base Flow + Alluvial Underflow + % Spring Discharge) n Evapotranspiration assumed minimal copyrig ight 2010, Sh Shell ll Explo loratio ion and Pr Productio ion Co., and it its affi filia liates 15 15 October r 20, 2010

Model Groundwater Recharge Distribution Location of A A ’ next slide cross-section n Correlates with topography n Areal distribution calibrates as well as alluvium-focused recha rge copyrig ight 2010, Sh Shell ll Explo loratio ion and Pr Productio ion Co., and it its affi filia liates 16 16 October r 20, 2010

Numerical Model Input and Layering n Layering based upon Layer Hydrostratigraphic Comments Zone Shell defined 1 Alluvium and Uinta Made inactive where dry cells occur 2 Upper Uinta Made inactive where dry cells occur hydrostratigraphy 3 Lower Uinta 4 R8 Seal unit between Uinta and Upper Parachute Creek n Model uses average 5 L7 “A-Groove” 6 R7 “Mahogany” Regional Seal unit parameters from 7 L6 “B-Groove” 8 R6 field tests as starting 9 L5 10 R5 Regional Seal unit point 11 Upper L4 L-4 unit split due to thickness (>300 ft) 12 Lower L4 n Values modified 13 R4 14 L3 during model 15 R2/GG/DC Seal unit between Lower Parachute Creek and Wasatch 16 Wasatch Set to 1000 ft thick uniformly. Lower sink. A calibration with ¡ A ’ SW to NE Conductivity/Layering observed heads and base flow discharges n TDS “ source ” above background in upper WBIs near discharge features such as Piceance Creek assumed due to nahcolite dissolution copyrig ight 2010, Sh Shell ll Explo loratio ion and Pr Productio ion Co., and it its affi filia liates 17 17 October r 20, 2010