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the seams located at 19-feet, 29-feet, and 36-feet appeared corroded to an extent where leakage would be probable. Vertical grooves (possible seams) in the casing were also observed throughout the length of the well. The total depth of the well is 65.7-feet bgs based on the initial well inspection performed. However, according to the video log, the bottom of the well is at a depth 50-feet bgs. This discrepancy is likely due to the "cleaning" of the well with the steel brush causing surrounding sediment to collapse, filling in the bottom of the well. The casing likely ends in t h e vicinity of 50-feet bgs with the remainder of the well being "open-hole." The cement-bond log indicated this well has a cement seal from the SWL of 10-feet bgs to 43-feet bgs. No casing slots were observed on the video log and water probably entered the well through the open-hole at a depth below 50-feet bgs. The pump intake was located at a depth of 54.5-feet bgs. Depending on the quality of the cement seal, it is possible that significant leakage could have also occurred through several of the seams noted above. If the cement seal is in good condition, then this well would not be considered a significant conduit for the vertical migration of MTBE. However, if the seal is in poor condition, then this well would b e considered a potential conduit for the vertical migration of MTBE due t o the numerous seams that may have leaked in the casing. 4.3 17904 South Airport Wav The domestic well at the above address is constructed with 5.5-inch I.D. steel casing. The total well depth is 69.6-feet bgs based on the initial well inspection performed. The video log of the well confirmed this depth. The bottom of the casing was observed at 65-feet bgs, leaving 4-feet of open-hole at the bottom of the well. Casing seams were observed at 14- feet, 47-feet, and 56-feet bgs. What appeared to be plugged holes were present at 54 and 56-feet bgs. The seam observed at 56-feet bgs appeared to have the potential to leak water based on the condition of the seam. The cement-bond log shows the presence of cement from the SWL of 10.5- feet bgs to a depth of 63-feet bgs. The presence of this cement is consistent with the appearance of the plugged holes located at 54 and 56- feet bgs. Water apparently entered the well through the open hole between 65 and 69-feet bgs. The pump intake was located at 42-feet bgs. Based on all of the available data, this well does not appear to be a significant conduit for the downward movement of MTBE in the site vicinity. Franks One Stop Report — February 2001 -3-