GENERAL DOCUMENTS - 10/20/2009, 7:56:37 AM-MR1

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The maximum possible retort volume needed to generate 2000 barrels of oil is about • 65,000 cubic feet. The largest diameter of the retorted zone will be near the perforations allowing oil from the boiling pool to enter the retort. Anticipated geometries range from a 50-ft diameter sphere to a 200-ft long cone with a 26-ft diameter near the perforations tapering smaller toward the top of the retort (top of the RI, see Figure 6-1). Subsidence calculations addressed the potential caving of rock above the retort until the rubblized rock and compressed retorted shale have sufficient strength to prevent further caving. Some fracturing may occur above that level to a height a few times higher than caving. The total height is called the ellipsoid of loosing. The maximum ellipsoid of loosing for a 50-ft-diameter sphere is about 220-ft above the top of the injection point. An injection point within the 2120-2135 feet depth interval would result in all fracturing terminating below the nahcolitic oil shale. The conical geometry is more likely. The top of its fracture zone would be less than 150 feet high, and an injection point in the 2070-2080 feet depth interval also results in all fracturing terminating below the nahcolitic oil shale. The retort will be monitored and it will be prevented from growing larger than acceptable. The total volume of shale retorted will be calculated continuously by monitoring produced fluid volumes, and the size and shape will be monitored by various geophysical methods. The criterion used will be that cross-sectional area of the retort at • any given depth along the heater-producer well will not exceed 20% of the distance from the well-bore to the base of the nahcolitic oil shale. In addition, AMSO will monitor groundwater as described in Section 5 of this application. 12. PLANS FOR WELL FAILURES In the extremely unlikely event of a well failure, AMSO will cease adding heat to the underground heater, remove any fluids from the heater-producer well, and shut in the heater-producer well. The cause of the well failure will be identified and rectified. The Pilot Test may be terminated or continued depending on the cause and extent of the well failure, and on the status of the Pilot Test. If the failure has the potential to contaminate USDWs, the EPA will be notified within 24 hours, and AMSO will submit a response plan to the EPA within three days. 13. GROUNDWATER MONITORING PROGRAM Please see Attachment 2 for the Operational and Post-Operational Sampling and Analysis Plan. Figure 13-1 presents a schematic diagram of monitoring well completion intervals. 0 23