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Evaluation of cement -American Soda #29-23 <br />CBL and CAST tools were run in the above listed well to 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 the bottom of the shorter string and cement is placed in the annulus from <br />[he cement basket to near surface. <br />The logs on [his 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 1,783' Frce Pipe (long string) No isolation 2.0 Flat consistent G2, Free pipe value strong <br />1,783' Cement Basket N/A N/A N/A N/A N/A <br />1,783' to 1,778' Bentonite Plug Good >2 Active, > mud value < free pipe value Slightly Faded <br />1,778' to 1,736' Mixture of Spherelite and conventional cmt Good 2 - 5 High activity < free pipe value Faded [o none <br />1,736' [0 1,710' Conventional cement Good 4 - 5 Med. To high Activity <I O None <br />1,710' [0 1,504' Mixture of Spherelite and conventional cmt Good I - 5 Med. To high Acuvity <10 None <br />1,504' to 510' Conventional cement Goad 2.5 -4.5 Medmm Activity <IO to 20 Faded to none <br />S l0' to 500' Partial cement, could communicate Poor 2.0 Flat consistent 58, Near free pipe value strong <br />500' [0 420' Conventional cement Good 3 - 4 Medium Activity < free pipe value Slightly Faded <br />420' to top of log Spherelite cement Good <I to 3 Low activity < free pipe value strong <br />Circumferential 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 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 aze: <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 />Cement Band 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 />