Antelope Hills Directionally Drilled Water Well. Theresa Jehn-Dellaport Jehn Water Consultants, Inc.

Transcription

1 Antelope Hills Directionally Drilled Water Well Theresa Jehn-Dellaport

2 Directional Well Applications Deep Bedrock Aquifers Proven Oil field technology Initial Analysis indicates up to 4 times the production capability More efficient well design Takes advantage of more of the available saturated thickness

3 Discussion Topics Hydrogeology Well Design Permitting Methodology Drilling Completion Development Pumping Test

4 Hydrogeology Sand occurs in horizontal lenses and usually not continuous Depositional Environment East to West

5 Flow in an Anisotropic Aquifer Flow lines do not cross equipotential lines at right angles Estimated that the horizontal conductivity can be up to 10 times that of vertical May also be related to depositional direction

6 U_ARAPAHOE [SGS] U_ARAP_BASE [SGS] L_ARAPAHOE [SGS] L_ARAP_BASE [SGS] LARAMIE [SGS] FXHL [3] MARKER1 [SGS]

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8 Antelope Hills Small Development, based on ground water Vertical Arapahoe Well Tested 90 gpm Sustained rate 50 to 60 gpm Laramie-Fox Hills higher production,?? Water Quality Need for a higher sustainable rate from the Arapahoe aquifer

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10 Well Design Apply Oil Field Technology Will a directionally drilled oil well design work for water?

11 Oil Field Horizontal Well

12 Oil Field Horizontal Well

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14 Well Design One sand does not an aquifer make Depositional environment east to west Budget Geophysical log ($$$$!!!!)

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17 Directional Well Goals Arapahoe aquifer is divided Lower aquifer has approximately 3 sand lenses Current vertical well is 60 gpm not sustained Target to increase to 120 gpm sustained

18 Permitting and Variance Approval Permitted as a normal water well permit Directional Portion of the Well Must Remain on the property Must be screened only in the target aquifer Directional Survey of the entire well Geophysical log of the entire well (obtained a variance for Antelope)

19 Methodology More precise than shallow application Use oil field services for the directional drilling Driller provides the equipment Use traditional mud rotary with mud motors Need to keep drilling speed down in water wells for cuttings removal

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21 Drilling Technology is proprietary to each company used Tools are attached to the bit Also includes a geophysical logging tool on drill stem to determine the formations Signals are sent up the borehole drilling fluid is the conductor for the signal

22 Drilling (Continued) Diaphragm Transducer picks up signal Software translates the signal Based on the magnetic of the earth True north and starting position are critical Traditional mud rotary Use of mud motors and mud pumps

23 Drilling (continued) Slide to build angle, mud motor spins, drill stem does not Rotating maintaining hole TVD Total Vertical Depth TMD Total Measured Depth

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27 Completion Screen Gravel Pack? Profile

28 /8-inch Casing Shoe feet (M.D.) inch I.D Lateral Leg SCALE 100 ft 1565 Gilpin St. Denver, CO ANTELOPE HILLS DIRECTIONAL WELL Lithologic Cross-section showing well path and screen placement Job No July 18, 2003 LEGEND Sandstone Layer Shale Layer Screened Interval Cased Interval Arapahoe aquifer Boundary

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32 Drilling Issues Rate of Drilling Good Mud Program is Critical Hole Integrity Cuttings Removal

33 Development Use of traditional mud rotary causes significant development concerns Fluids Removal Cautious use of air for development Surge Block Methodology

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35 Pumping Test Transducers at either end of the well Analysis virtually identical at both ends Compared to vertical Arapahoe Well at site location

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37 /8-inch Casing Shoe feet (M.D.) inch I.D Lateral Leg SCALE 100 ft 1565 Gilpin St. Denver, CO ANTELOPE HILLS DIRECTIONAL WELL Lithologic Cross-section showing well path and screen placement Job No July 18, 2003 LEGEND Sandstone Layer Shale Layer Screened Interval Cased Interval Arapahoe aquifer Boundary

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40 Dropped from 90 to 80 gpm 80 to 70 gpm 80 to 70 gpm 80 to 70 gpm 70 to 65 gpm Recovery to 80 gpm 70 to 80 gpm 300 Drawdown (ft) Directional Water Level Vertical Water Level Recovery ET (seconds)

41 Recovery Data 48 hr Test Vertical Water Level Directional Water Level Drawdown ET (seconds)

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47 Specific Capacity Existing Vertical Well gpm/ft Directional Well gpm/ft

48 Lessons Learned Development Well Design Oil Field Contractor

49 Next Steps Recharge Increase production Sustainability Modified design

50 /8-inch Casing Shoe feet (M.D.) inch I.D Lateral Leg SCALE 100 ft 1565 Gilpin St. Denver, CO ANTELOPE HILLS DIRECTIONAL WELL Lithologic Cross-section showing well path and screen placement Job No July 18, 2003 LEGEND Sandstone Layer Shale Layer Screened Interval Cased Interval Arapahoe aquifer Boundary