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Evaluation of cement -American Soda #29-28 <br />CBL and CAST tools were tun in the above listed well [o evaluate the placement and quality of the cement slurry. CBL/CAST logs were run in both casings, from the base <br />of each string to surface or to the Fluid level in [he casing string. A cement basket is positioned near [he bottom of the shorter string and cement is placed in the annulus from <br />the cement basket to near surface. <br />The logs on this well indicate the following: <br />Depth Interval Description Isolation <br />Evaluation CAST <br />Impedance Value CAST <br />Impedance Character CBL Pipe Amplitude MSC pipe signal <br />TD l0 1,860' Free Pipe (long string) No isolation I.5 Flat consistent 65, Free pipe value strong <br />1,860' Cement Basket N/A N/A N/A N/A N/A <br />1,860' to 1,854' Bentonite Plug Good >2 Medium activity < free pipe value Faded Slightly <br />1,854' to 1,436' Mixture o(Spherlite and conventional cmt Good <I - 5 Med. To high Activity Low, primarily < 10 Faded to none <br />1,436' to 1,412' Conventional cement Good >3 Medium activity Low, < 10 Faded [o none <br />1,412' to 1,303' Mixture of Spherlite and conventional cmt Good <I - 5 Med. To high Activity Low, primarily < 10 Faded to none <br />1,303' [0 615' Conventional cement Good >3 Medium activity Low, < 10 Faded to none <br />615' [0 320' Mixture of Spherlite and conventional cmt Good <l - 4 Med. To high Activity Low, primarily < 20 Faded < free <br />320' [o [op of log Spherlite cement Good <I - 3 Low activity, consistent < free pipe value Faded < free <br />Circumjerentia/ Acoustic Scanning Too[ (CAST) impedance values for fluids are very consistent and manifests itself as a fairly straight line on the log. Cement slurries, <br />are more variable and show up as curves with much more activity or variability. By analyzing [he value and [he character of the impedance curves, it is possible to <br />successfully evaluate [he cement quality of conventional and lightweight cements. Typical impedance values for common materials or Fluids are: <br />Gas or air < .5 high activity curve response <br />Water 1.5 flat consistent curve response <br />Drilling Mud 1.5 - 2.5 flat consistent curve response <br />Lightweight Cements <I - 4 high activity curve response <br />Conventional Cements 2 - 6 medium to high activity curve response depending consistency of sh[try <br />Cement Bond Log (CBL) tools evaluate cement bonding to pipe and formation by measuring the changes in sound waves traveling through casing, cement, <br />and formation. Log presentations include a pipe amplitude curve and aMicro-Seismogam ®display in the form of light to dark shades. The amplitude <br />curve in lightweight cements will not read as low as published values for conventional cements. Comparisons to lowest value and to free pipe value are <br />necessary to fully evaluate. Pipe signal will not completely disappear in lightweight cement as in conventional cements. <br />Respectfully, <br />Tom Riebel <br />Halliburton Energy Services <br />