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The project comprises three wells for heating and one well for observation and /or pressure control <br />(Figure 6). Plans call for all wells to be drilled prior to deploying and activating any of the heaters. <br />The horizontal wells will be drilled with directional control from surface, with a kick off point <br />(KOP) between 1,000 ft to 1,400 ft true vertical depth (TVD) and a build rate of 5° to 10 °/100 ft <br />(dog leg severity) to a maximum inclination of 90 °. The horizontal section for these wells will be on <br />the order of 1,000 ft to 1,150 ft and an inclination at well total depth (I'D) between 90° and 93° to <br />allow deploying the heaters in the formation bedding planes (up dip). The total depth of the deepest <br />horizontal well (located at the heel) is projected to be less than 2,650 ft TVD. <br />The inclined well will be drilled with directional control from surface with a KOP between 200 ft to <br />400 ft TVD with a build rate between 5° to 10 °/100 ft up to an inclination between 30° to 60° <br />which will be maintained to 'I'D. Total depth of the inclined well is projected to be less than 2,550 ft <br />TVD. <br />Fresh water will be transported to the site from the White River the City of Meeker or other <br />available sources for use in all drilling. Cuttings and drilling fluids will be transferred to an onsite <br />dewatering pit where the water in the cuttings will be allowed to infiltrate back to ground water. <br />Dewatered cuttings will be transferred to rolloff boxes and transported to applicable offsite facilities <br />for permanent disposal. Surface and intermediate hole sections will be drilled with aerated mud and <br />loss circulation material added as required, and the horizontal section with aerated mud and loss <br />circulation material or common water well drilling lubricant depending on the borehole stability <br />studies simulations which are yet to be concluded. <br />The wells will be constructed with pressure or temperature sensors to monitor changes in each <br />pyrolysis interval and in the crown above upper pyrolysis interval. Geological conditions at the <br />ELHT are very well informed by the recent drilling of Shell appraisal well 135 -4 -298 (SAW -1 well), <br />the five hydrology wells on the 138 -4 -298 Pad, and of the 20 ERDD wells. Ground water is <br />expected at about 250 ft depth, based on the water level in well 135 -4-298 (SAW -1 well). <br />Wells drilled by Shell in the Piceance Basin in the past 10 years generally encountered small amounts <br />of gas, particularly in the deeper formations. The gases contain mostly N2 and CH with lesser <br />volumes of 0 and CO (Schatzel et al, 1987). Hydrogen and ammonia may be present. Samples <br />collected in closed containers for up to 125 days contained up to 0.195 cm /g of gas. <br />A sulfur odor often is detected in drilling of Uinta and some of the shallow Parachute Creek wells. <br />Although LEL (lower explosive limit) measurements are checked at all wells during drilling, and <br />even though methane and sulfur gas occur typically, LELs have never been exceeded. If unusual gas <br />levels are encountered, drilling will be shut down and the well will be allowed to vent. <br />5.4.2 Casing Cement Processes <br />Surface (conductor) casing will be set in cement by placement of cement directly in the annulus of <br />the conductor, by a tremmie pipe or through a stab -in cementation in which a cement stinger is run <br />and stab -in into a float shoe and pump cement into the annulus until returns are seen at surface. <br />Conductor casing cement will be Type I /II premium plus cement. <br />9 <br />