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Evaluation of cement -American Soda #20-19 <br />CBL and CAST tools were run in the above listed well [o evaluate the placement and quality of [he cement slung. 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 [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 MSG pipe signal <br />TD [0 1,708' Free Pipe (long string) No isolation 1.9 Flat consistent 62, Free pipe value strong <br />1,708' Cement Basket N/A N/A N/A N/A N/A <br />1,708' to 1,702' Bentonite Plug Good >2 Active, > mud value < Gee pipe value Slightly Faded <br />1,702' [0 1,693' Partial cement, could communicate Poor 2.0 Flat consistent 58, Near Gee pipe value strong <br />1,693' to 1,666' Spherelite cement Good 2 to 3.5 Medium Activity < free pipe value Slightly Faded <br />1,666' [0 700' Mixture o(Spherelite and conventional cmt Good <I - 5 Med. To high Activity <Gee pipe value Slightly Faded <br />700' [0 696' Partial cement, could communicate Poor 2.0 Flat consistent 56, Near Gee pipe value strong <br />696' to 542' Spherelite cement Good <I to 2.5 Med. To high Activity < Gee pipe value Slightly Faded <br />542' [0 536' Partial cement, could communicate Poor 2.0 Flat consistent 52, Near free pipe value strong <br />536' [o top of log Spherelite cement Good <I to 3 Low to medium activity < Gee pipe value Slightly Faded <br />Circumjerentio! Acoustic Scanning Too/ (CAST) impedance values for Fluids are very consistent and manifests itself as a fairly straight line on [he 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 [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 crave response <br />Lightweight Cements <I - 4 high activity curve response <br />Conventional Cements 2 - 6 medium [o high activity curve response depending consistency of slung <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 />Halliburton Energy Services <br />