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Evaluation of cement -American Soda #29-24 <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 run in both casings, from the base <br />of each string [o surface or to the fluid level in [he casing string. A cement basket is positioned near the bottom of [he shorter string and cement is placed in [he 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 [0 1,767' Free Pipe (long string) No isolation 1.4 Flat consistent 68, Free pipe value snong <br />1,767' Cement Basket N/A N!A N/A N/A N/A <br />1,767' to 1,650' Mixture of Spherelite and conventional cmt Good <I - 5 Med. To high Activity < 30, < free pipe value Faded <br />1,650' to 1,622' Partial cement and free fluid Poor I - 3 Low activity to flat < 20 Faded <br />1,622' [0 1,407' Conventional cement Good <I - 3 Med. To high Activity < 10, < free pipe value Faded <br />1,407' [0 1,400' Partial cement and free fluid Poor I.5 Flat consistent 50, near free pipe value Snong <br />1,400' [0 1,040' Mixture of Spherelite and conventional cmt Good 2 - 3 Medium Activity < 30, < free pipe value Slightly Faded <br />1,040' to 1,000' Partial cement and free fluid Poor 1.8 - 2 Flat consistent Up to40 < free pipe value Strong <br />1,000' to 272' Mixture of Spherelite and conventional cmt Good 2 - 4 Med. To high Activity < }0, < free pipe value Slightly Faded <br />272' to top of log Spherelite cement Good <I to 2+ Low Activity < free pipe value Slightly Faded <br />Circumjerenria( Acoustic Scanning Tao/ (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 troves, 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 l.5 - 2.5 flat consistent curve response <br />Lightweight Cements <1 - 4 high activity curve response <br />Conventional Cements 2 - 6 meditun to high activity curve response depending consistency of slurry <br />Cenrertl Bond Lag (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 lightwetght cement as in conventional cements. <br />Respectfully, <br />Tom Riebel, Halliburton Energy Services <br />