This old well

While watching the local TV news show, you see a report about ground water contamination and how it effects farms which get their water from wells.  For dramatic effect, the reporter stands next to an old style well which still works by lowering a bucket at the end of a rope into a deep hole in the ground to get water.  At the top of the well a cylinder is mounted to raise and lower the bucket, which the reporter mentions is solid oak.  To demonstrate the depth of the well, the reporter completely wraps the rope around the cylinder, with the bucket hanging from the end.  She then releases the bucket, at rest near the cylinder, and it descends to the bottom of the well unwinding the rope from the cylinder as it falls.  It takes 2.5 seconds.  She doesn't tell you the depth of the well so you decide to calculate it.  You estimate that the cylinder has the same mass as the bucket and assume that the mass of the rope and any friction can be neglected.