This study area (T. 1-5, R. 15-22W4) of the Bow Island reservoir involves testing ~200 wells. Each well is given a letter, which is the quality code of the drillstem test (DST). The letters range from A, the highest quality test, to G, a misrun. A, B, C quality tests generally have good pressure data. D quality tests have pressures that can be plotted on the PE map, but there is much uncertainty in the value. The DSTs with quality pressure codes A to D have been classified as upper on lower Bow Island. Tests, which lay within an interval from the Base Fish Scale (BFS) marker plus 40m were classed as upper Bow Island. The most obvious feature of the PE graph is the considerable data scatter. This scatter of pressure data can be divided into three systems that grade into each other and form three distinct areas on the recovery map.