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SWEPI LP Well HW 8101 <br />Executive Summary <br />Purpose: Evaluate the cement bond in the well HW 8101. <br />Solution Methodology: Determine the quality of the cement behind the 7 -5/8 ", 26.4# casing in HW <br />8101 using the Schlumberger's Isolation Scanner and CBL -VDL Tools. <br />General: The well HW 8101 is a producer well in a 9 -5/8" borehole drilled to 2295ft and then under - <br />reamed to a 12 -1/4" diameter from 2138ft to 2295ft. An 11.5ppg pill was spotted at TD prior to <br />running 7 -5/8 ", 26# casing from surface to 2127ft. The 7 -5/8" casing was cemented with 131bbls of <br />9.5ppg litecrete light weight cement followed with 22bbls of 15.8ppg class G cement. Plug was <br />bumped with water and 1200psi, tested to 1500psi for 15minutes. 62bbls of cement returned to <br />surface. During the drilling stages, no cement plugs were placed in the well at various borehole <br />intervals to prevent loss circulation and hence ensure a quality cement job for the 7 -5/8" casing. <br />The well was logged with the Schlumberger's Isolation Scanner and CBL -VDL Tools on 06- Dec -2012. <br />A combined CBL -VDL /Isolation Scanner presentation is in this report. <br />The Schlumberger's Isolation Scanner cement evaluation service provides more certainty for light <br />weight cements by combining the pulse -echo technique with a new ultrasonic technique that <br />induces a flexural wave in the casing with a transmitter and measures the resulting signal at two <br />receivers. The attenuation calculated between the two receivers provides an independent response <br />that is paired with the pulse echo measurement and compared with a laboratory — measured <br />database to produce an image of the material behind the casing. By measuring radially beyond <br />traditional cement evaluation boundaries, Isolation Scanner service confirms zonal isolation. <br />Both the conventional CBL -VDL and ultra sonic pulse -echo techniques rely on a significant contrast in <br />acoustic impedance between the cement and the displaced drilling mud to determine whether or <br />not: a) there is cement behind the casing rather than drilling mud and b) the cement is bonded to <br />the casing and the formation. Due to the use of light weight cement in this well which results in <br />lower contrast, the conventional CBL -VDL and ultra sonic pulse -echo techniques have to be <br />supported with the Schlumberger's Isolation Scanner tool. <br />Summary of Findings: The Isolation Scanner Log from the raw curve measurements and all the <br />images indicate Top of Cement (TOC) at 290ft. <br />Three different zones of cement bond log quality can be seen from the analysis as follows: <br />Zone 1- 1550ft — 2127ft: The flexural image map indicates cement is present in the annulus behind <br />the casing and that casing is bonded. Adequate isolation exists. The conventional CBL -VDL log shows <br />low amplitude in this tail slurry cemented interval. The VDL shows presence of formation arrivals in <br />this interval. The transition to lead cement is observed at 1560ft. <br />Zone 2 - : 290ft — 1550ft: This interval is across the lead cement slurry. The flexural image map <br />indicates the presence of the light weight cement and hence hydraulic isolation exist. <br />