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Evaluation of cement -American Soda #29-27 <br />CBL and CAST tools were run in [he above listed well to evaluate the placement and quality of the cement slurry. CBL/CAST logs were twt in both casings, from the base <br />of each string to surface or to the fluid level in the casing string. A cement basket is positioned near the 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 MSG pipe signal <br />TD [0 1,772' Free Pipe (long string) No isolation 2 Flat consistent 60, Free pipe value strong <br />1,772' Cement Basket N/A N/A N/A N/A N/A <br />1,772' [0 1,768' Bentonite Plug Good >2 Medium activity < free pipe value Faded Slightly <br />1,768' to 1,145' Mixture of Spherlite and conventional cmt Good I - 5 Med. To high Activity Low, < 20 Faded to none <br />1,145' to 1,106' Sherelite cement Good <I Low to medium activity Low, < 20 Faded Slightly <br />1,106' to 550' Mixture of Spherlite and conventional cmt Good I - 3.5 Med. To high Activity Low, < 20 Faded [o none <br />550' [0 [op of log Sherelite cement Good <I Low to medium activity < free pipe value Faded Slightly <br /> <br />Circumjererrtia[ Acoustic Scanning Too/ (CAST) impedance values for fluids are very consistent and manifests itself as a fairly straight line on the log. Cement slturies, <br />are more variable and show up as curves with much more activity or variability. By analyzing the value and the character of the impedance curves, it is possible to <br />successfully evaluate the 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 <l - 4 high activity curve response <br />Conventional Cements 2 - 6 medium to high activity curve response depending consistency of slurry <br />Cemerr! 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-Seismogram ®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 />