2012-12-12_REVISION - P2010026 (3)

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well TD which contains the three phase MI heater and an instrumentation package including thermocouples and an optical fiber. The canister will be equipped with a pinned open expansion sleeve. An intermediate 13 -3/8 in casing will be considered in the design as contingency to isolate the upper loss zone prior penetrating the dissolution surface. This casing could eventually be integrated in the design to maximize the chances of drilling the well safely to TD. If this is the case, then the bigger conductor size will be used (20 in) and there will be two potential options to drill the intermediate interval: • Drill a 17 -1/2 in hole below the conductor to a safe casing point below the loss zone and then run and cement to surface the 13 -3/8 in casing • Drill a 12 -1/4 in pilot hole, asses the loss rate and then under ream the hole to 17 -1/2 in and run and cement to surface the 13 -3/8 in casing. 5.4.5 Inclined Observer /Producer Well The main function of the inclined observer /producer well is to provide monitoring and back -up pressure control of the fluids /gases generated during the heating process. This well will be drilled from the same pad as the horizontal heater wells to minimize surface disturbance. The well will be inclined between 30° and 60° inclination and will pass the deepest heater well at approximately 700 ft to 800 ft from the heel. The distance between the Producer / Observer well and each horizontal heater well will be between 5 ft and 20 ft. As presented in table 6.1, Producer / Observer well design (Figure 8) will consist of a 13 -3/8 in conductor set into the bedrock and cemented to surface, followed by a 12 -1/4 in hole drilled through the bend section and inclined between 30° to 60° to the casing point (between 2,000 and 2,200 ft TVD) to run and cement to surface a 9 -5/8 in casing string. Subsequently, an 8 -1/2 in hole (inclined between 30° to 60 °) will be drilled to well TD to run a 6 -5/8 in slotted liner. The well will be completed with a 2 -3/8 in tubing string containing a plunger lift system and instrumentation to monitor pressure and temperature at each pyrolysis interval. Instrumentation to monitor the temperature in the cap above the upper pyrolysis interval will be attached to the casing OD and cemented in place. 5.4.6 Cuttings and Drill Water Disposal Cuttings and drilling fluids will be transported to a temporary cuttings pit located on the EAST RDD project site. Water contained in the cuttings and drilling fluid from above the L4 will be returned to the subsurface by means of infiltration and the dewatered solids will be loaded in portable tanks and transported to applicable offsite facilities for permanent disposal. 5.5 Development Methods, In Situ Methodology 5.5.1 Operational Phases and Timeline The ELHT Pilot will span — 4 years and is run concurrently with the East RDD Pilot. Drilling, depending on the time needed for permitting and procurement of equipment, is expected to begin in 11