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C) <br />Yellow <br />Blue <br />Light Green <br />Dark Green <br />As shown by the light green shading and the corresponding red flags in the depth track of <br />each well log, there are long continuous intervals having 80% bond index. Based upon <br />my review of the BI logs, hydraulic isolation is demonstrated in all required intervals <br />except in the TM -2 Retort/L3 interval and above the Uinta HU in the TM -2 and TM -3. <br />The lower part of the TM -2 well is discussed below in reference to AMSO's retort <br />isolation test. In the shallowest portions of the wellbores, the CBL response is clearly <br />affected by the expanded foam cement. True free pipe readings of around 75 mV are <br />only seen in the TM -2 above 328 ft. and in the TM -5 above 250 ft. These readings are <br />confirmed by stretch free point determinations. Intermediate amplitude readings, for <br />example in the TM -3 from surface down to 650 ft of around 50 mV indicate the presence <br />of a low attenuation material, probably an expanded foam cement responding to lower <br />wellbore pressures. Importantly, these readings show the presence of circulated cement <br />behind pipe. In these intervals the Halliburton CAST /ACE and Schlumberger IBC logs <br />must be used to identify cement and hydraulic isolation. <br />TM - 2 RETORT ISOLATION TEST <br />equal to or greater than 60% BI <br />equal or to greater than 70% BI <br />equal to or greater than 80% BI <br />equal to or greater than 90% BI <br />Due to the low BI readings in the lower portion of the TM -2 well, AMSO conducted a <br />retort isolation test. This test was undertaken to confirm hydraulic isolation between the <br />Retort Zone and the L3 HU. The test was performed using a wireline conveyed cutting <br />tool to cut the casing in the TM -2 at approximately 1975 ft. After the casing was cut, all <br />fluid in the TM -2 wellbore was evacuated. This imposed a differential pressure of <br />approximately 700 psi on the 4 1 /2" casing's annular cement between 1975 ft. and the L3 <br />HU. No fluid was recorded from the casing cut, meaning the cement displayed hydraulic <br />integrity. This zone exhibited only 70% bond index and Halliburton CAST /ACE log <br />readings of "fair ". The Schlumberger IBC logs showed channeling in this interval. The <br />results of this test confirm that: <br />1. Halliburton CAST /ACE interpretations of "fair" (or better) can be equated to <br />cement bond and cement placement that provide hydraulic isolation. <br />2. Schlumberger IBC log readings accurately predict hydraulic isolation, but <br />identified channels and voids do not equate to hydraulic flow paths. <br />3. " Calibrated bond index determinations of 70% (of approximately 50 ft. in <br />length) provide hydraulic isolation. <br />ASSESSMENT OF SHALLOW ZONES <br />As noted above in the CBL/VDL discussion, hydraulic isolation cannot be confirmed by <br />BI calculations alone for the Uinta HU in the TM -2 and TM -3. However, the results of <br />TM -2 retort isolation test allow the Halliburton CAST /ACE and Schlumberger IBC log <br />