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Evaluation of cement -American Soda #29-26 <br />CBL and CAST tools were mn in the above listed well to evaluate the placement and quality of the cement slurry. CBL/CAST logs were mn in both casings, from the base <br />of each string [o surface or to [he 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 />the cement basket [o near surface. <br />The logs on this well indicate the following: <br />Depth Interval Description Isolation <br />Evaluation CAST <br />Impedance Value CAST <br />Impedaoce Character CBL Pipe Amplitude MSG pipe signal <br />TD t0 1,817' Free Pipe (long string) No isolation I.8 Fla[ consistent 62, free pipe value strong <br />1,$17' Cement Basket N/A N/A N/A N/A N/A <br />1,817' to 1,812' 8entonite Plug Good 2 Medium activity < free pipe value Snong <br />1,812' to 756' Mixture of Spherlite and conventional cmt Good <1 - 4.5 Med. To high Activity Variable, always < free pipe Faded to none <br />756' to 740' Partial cement and free fluid Poor 1.8 - 2 Flat consistent in spots Up to35 < free pipe value Faded Slightly <br />740' [0 380' Mixture o(Spherlite and conventional cmt Good 2 - 3.5 Medium activity Low, primarily < 20 Faded Slightly <br />380' [o [op of log Spherlite cement Fair <1 - 3 Med. To high 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 [he impedance craves, 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 />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-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 />Halliburion Energy Services <br />