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Video Transcript: Three Mile Island, Unit 2: Removing Lower Debris

[Time Stamp: 00:00] In 1985, cameras were lowered through the annular space between the core support assembly and the reactor vessel wall.

[Time Stamp: 00:07] On the way down, the visible external surfaces of the core support assembly were inspected to see if any structural damage occurred.

[Time Stamp: 00:15] Not only was there no damage of any kind visible on the core support assembly, there was little or no debris accumulation in this region.

[Time Stamp: 00:23] In the lower head region, however, piles of rubble-like debris were found.

[Time Stamp: 00:28] It was estimated that there are ten to twenty tons of rubble in the lower head.

[Time Stamp: 00:33] Also visible was debris hanging down through some of the flow holes in the flow distributor head.

[Time Stamp: 00:40] The material appears to have been molten and possibly fractured on cooling.

[Time Stamp: 00:44] On the North side of the lower head was found a wall of debris, standing fifteen inches high and over five feet wide.

[Time Stamp: 00:54] The second inspection path put a camera right in the center of the lower head.

[Time Stamp: 00:59] During the core bore operation, a camera was lowered all the way through the lower CSA and the flow distributor head into the lower head region.

[Time Stamp: 01:08] The debris in the center of the lower head was granular and was piled up almost to the flow distributor head.