Three Mile Island

Londonderry Township - Susquehanna River, Pennsylvania
Class VIII - Environmental Condition, Nuclear Power Plant Disaster

The Three Mile Island (TMI) nuclear power plant started construction in 1968. The plant has two units. Unit 2 began commercial operation in December, 1978. On March 28, 1979, a valve stuck and river water used to cool the nuclear core flowed out of the reactor's system. The core overheated and some radioactive material (within prescribed limits) was released into the atmosphere. The core temperature reached 5,000 degrees F. TMI came within one hour of a "Group 1" accident - a complete meltdown with failure of the backup safety system, which was considered a near impossibility, calculated at 1 chance in 200 million reactor years. Local residents were advised to evacuate the area.

The full extent of damage was not known until mid-1982, when a report camera showed that about 90% of the 37,000 fuel rods were damaged. Cleanup was completed 14 years after the accident. The subsequent cleanup took the efforts of over 1,000 people and cost $973 million. Unit 1 was never damaged and still operates today. Some new research indicates that cancer levels are up to 10 times higher for people living downwind of the reactor.

The areas immediately nearby TMI are predominately scarcely populated farmlands. Interviews with numerous local residents indicate that there are mixed reactions related to real estate values. The local farms are owned predominately by families who have long-term ties to the area. Many of these residents indicated that they never left the area, even during the period of the initial accident. However, one developer indicated that it was virtually impossible to sell property in the immediate area, and only after waiting approximately one and one-half years after the accident were they able to sell a spec-built home at a 30% discount. In more nearby urban areas, particularly Harrisburg, real estate values remained level or even increased. This phenomena was attributed to the fact that only 200 workers were displaced by the accident, but new demand was created by the over 1,000 new workers being employed for the 14-year clean-up. At the time of the last field-inspection (1997), virtually all parties agreed that the incident no longer impacted real estate values. Some people stated that their concerns with TMI are receding, while their concerns over the noise from the local airport (Harrisburg International) are increasing.