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H01 well only, temperature in the crown will also be monitored with a dual thermocouple attached to
<br />the outside of the longstring casing at depths of 1,990 feet and 2,060 feet. Additionally, two
<br />transducers will also be placed on one of the tubing strings to provide continuous temperature and
<br />pressure readings near the top and base of the targeted mine interval, at approximately 2,122 feet
<br />and 2,260 feet.
<br />A number of kerogen pyrolysis experimental studies have been performed to determine the kinetic
<br />rates as a function of temperature. By weight, Green River Shale Is approximately 10% shale oil. At
<br />temperatures below 500 deg F, only 10% of the shale oil is extractable, or 1% by weight of the
<br />formation. Those experiments, conducted in organic solvents, evolved higher amounts of kerogen
<br />than can be expected for actual conditions where heating takes place in groundwater. In general, the
<br />kinetic relationship between the temperature and the time is governed by Arrhenius' law, where, at
<br />higher temperatures, a shorter amount of time is required for the shale oil to be produced. At lower .
<br />temperatures, the amount of time exponentially increases. Using the' reaction constants from the
<br />Bumham, et al, 1987' paper, at 400 deg F, it would take over 1.7 years before the kerogen in the
<br />shale oil is generated. Therefore, at a maximum temperature of 400 F, and an Injection duration
<br />of less than 1 year, oil is not expected to be generated during the project life. Shell is permitted to
<br />operate at a maximum temperature of 400 deg F, however, Shell intends to operate at their design
<br />surface temperature of 350 deg F 10 achieve a 300 deg F within the injection zone. Additionally,
<br />along the welibore, Insulation is provided by the N2 blanket, longstring steel casing, and cement
<br />behind the casing, to further minimize effects to the formation away from the injection zone. The
<br />permit duration is for the fife of the project, however the leaching phase is 1 year or less, and the
<br />total duration of the experimental project that will Include the leaching and pyrolysis phase is not
<br />expected to exceed ten years. In the event that the project exceeds the planned period of injection,
<br />the following table provides the number of days that injection is allowed at temperatures below 400
<br />• degF.
<br />Temperature deg F
<br />370
<br />371 - 380
<br />381 390
<br />391 — 400
<br />Number of Days
<br />4,417
<br />• 2,276
<br />. 1,191
<br />633
<br />Number of Years
<br />—12
<br />—6.2
<br />—3.3
<br />—1.7
<br />LEACHING INTERVAL MONITORING
<br />During -the injection phase of this Shelf intends to in -situ solution mine nahcolite from the
<br />Saline Zone. The targeted interval is approximately 153 feet in height and, will have an average
<br />radius of 20 feet. The geometry of the leached mass will be affected by the variable rates of
<br />nahcolite dissolution, which depends on nahcolite richness, morphology, and connectivity between
<br />nahcolite segregations. Nahcolite rich layers that are most susceptible to leaching have larger
<br />leach radii than nahcolite poor, and leachable layers that come in contact with the leach solution will
<br />have the fastest and largest amount of lateral penetration.
<br />Leaching interval development shall be monitored to estimate the extent to which the nahcolite has
<br />been produced. Because the leached solution interval will be a matrix of oil shale rather than a void,
<br />size and shape must be determined by indirect methods. Material balances of the volumetric fluid
<br />flow rates into and out of the leaching interval shall be performed. Continuous monitoring of flow
<br />rates and densities will provide an ongoing material balance, which will allow the Permittee to make
<br />calculations of the mass of nahcolite extracted, and this information will be submitted with the
<br />quarterly report.
<br />„ Comparison of Methrodsfor Measuring Kerogen Pyrolysis Rates and Fitting Kinetic Parameters" by Burnham et al. UCRL-95660 193rd Meeting of the
<br />American Chemical Society, Denver, Colo. (Apr. 5, 198D
<br />Permit CO32210 -00000 15
<br />Statement of Basis
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