2013-12-18_HYDROLOGY - P2010026 (7)

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SWEPT LP Purpose: Evaluate the cement bond in the well LHW 8118. Solution Methodology: Survey the casing with Isolation Scanner and CBL -VDL Logs. Well: LHW 8118 General: The well LHW 8118 is a heater well with an 8 -1/2" lateral open hole below a 9 -5/8" casing from surface to 2853ft inside a 12 -1/4" hole. The float collar is at 2850ft. The well has a 1/4" bubbler tube instrumentation line on the back side of the 9 -5/8" casing. CBL -VDL and Isolation Scanner Tool was tractor conveyed from 2650ft to surface as the tool string could not go below 2650ft. This report covers a combined CBL -VDL and Isolation Scanner presentation. During the cementing operations, LiteCrete cement of 9.5ppg and tail slurry of 15.7ppg was pumped in. No returns to surface were achieved during the cementing jobs with 190bbls of the displacement away. A copy of the EP Wells Daily Operation Report dated 27- Aug -2013 is presented on page 12 of the report. The Schlumberger's Isolation Scanner cement evaluation service provides more certainty for light weight cements by combining the pulse -echo technique with a new ultrasonic technique that induces a flexural wave in the casing with a transmitter and measures the resulting signal at two receivers. The attenuation calculated between the two receivers provides an independent response that is paired with the pulse echo measurement and compared with a laboratory — measured database to produce an image of the material behind the casing. By measuring radially beyond traditional cement evaluation boundaries, Isolation Scanner service confirms zonal isolation. Both the conventional CBL -VDL and ultra sonic pulse -echo techniques rely on a significant contrast in acoustic impedance between the cement and the displaced drilling mud to determine whether or not: a) there is cement behind the casing rather than drilling mud and b) the cement is bonded to the casing and the formation. Due to the use of light weight cement in this well which results in lower contrast, the conventional CBL -VDL and ultra sonic pulse -echo techniques have to be supported with the Schlumberger's Isolation Scanner tool. Summary of Findings: The Isolation Scanner Log from the raw curve measurements and all the images indicate Top of Cement (TOC) at 1180ft. A one page CBL -VDL and Isolation Scanner Presentation is shown on page 8 of the report. Four different zones of cement bond log quality can be seen from the analysis as follows: Zone 1- 2198ft — 2650ft: The top of the tail cement is at approximately 2198ft with fair cement. This is close to expected top of slurry (using 0% excess calculation). This suggest that circulation was lost above this depth. Adequate isolation exists with this tail cement bonded interval to isolate the open hole below the casing shoe. There is indication of good azimuthally covered solids from the bottom log interval to the lead /tail interface at 2198ft from the cement maps. Zone 2 -1453ft — 2198ft: This is interval where Lite Cement is present. The flexural image map showing good cement. The good cement across the R5 seal is isolating the saline water interval from overlying fresh water bearing intervals. 4 1 P a g e