Laserfiche WebLink
control leaching effectiveness. Potential upward leaching of hot water solutions into the crown <br />will be minimized by a nitrogen blanket, which will be applied at sufficient pressure to inhibit <br />upward movement of the leach fluid. <br />Drilling will be sequenced as follows. Conductor casing will be installed to — 40 - 60 ft depth, as <br />described above, into a 14 in. diameter hole and cemented. A 9'/8 in. hole will be drilled to the <br />top of the leaching and pyrolysis zone; 7 in. casing (26.4 #, J -55, LTC) will be placed inside and <br />cemented by displacement to the surface. <br />The leach well will then be drilled through the base of the TI bed (2,273 ft), deeper than the <br />heater wells, with additional footage to accommodate logging tools and a cleanout sump. Within <br />this casing, two sets of ^2 in. tubulars will be installed; one set to near the base of the TI bed; <br />the other placed approximately mid -way between the casing shoe and top of TI bed. <br />Leaching fluids will be injected via the shorter tubular and recovered (pumped) from the longer <br />tubular. <br />6.4.5. Heater Wells <br />Twelve heater wells will encircle the single leaching / heater well in the center of the heater <br />pattern (Figure 25). The Heater well construction (Figure 32) is similar to the dissolution well, <br />but with the addition of a thick wall sealed canister to contain the heater. (The central leach well <br />will be converted to a heater well after leaching.) A packer will be placed inside the casing, just <br />above the shoe so that the well will remain sealed below the packer and shoe. <br />6.4.6. Producer Wells <br />Producer wells (Figure 33) include a 9'/8 in. hole drilled inside the surface casing to top of the <br />heater zone with a 61/2 in. open well below with a 51/2 in. slotted liner for oil production drilled to <br />TD. The 9'/8 in. hole is cased with 7 in. 26.4# K -55 LTC casing and cemented to surface by <br />cement displacement. A slotted liner will be hung from a liner hanger just above the base the <br />shoe. The 2 % in. production tubing with an insert pump at the base will be placed in the open <br />hole to near the base of slotted liner, — 42 ft above TD. Two strands of in. capillary pressure <br />tubes and a wired sensor will be attached to the 2% in. tubing. A diluent string will be strapped <br />also to the producer string. <br />6.4.7. Observer Wells <br />Observer wells (Figure 34) will consist of 41/2 in. O.D., 11.6 #, J -55, LTC casing, cemented to <br />surface, inside 7% in. 26.4 #, J -55 STC conductor casing. The observer well 41/2 in. casings will <br />be sealed at the base. Casings may be fit with any of an array of instrumentation to measure <br />temperature, pressure or geomechanical stresses. <br />Notice of Intent 38 Shell Frontier Oil & Gas Inc. <br />December 2010 <br />