Abstract: A multi-purpose downhole tool comprising packers for isolating an interval of a downhole formation traversed by a borehole to form a packed-off interval annulus. The tool further comprises a reversible pump and more than one interval access port located between the packers. The ports provide fluid communication with fluid in the packed-off interval annulus. The tool further comprises a fluid conduit system and valves for controlling fluid communication between the interval access ports and the reversible pump. The multi-purpose tool is capable of pumping from the packed-off interval annulus as well as pumping into or “through” the packed-off interval annulus for determining formation pressures as well as introducing well enhancement fluids downhole.