INES-event
INES 1

Drop of a source into a logging well

On the 21st of January 2019 a well-logging geophysical probe containing 239 GBq activity 241-Am-Be sealed source was dropped to the bottom of a1800 m deep well near Pecs city, Hungary. The cause of the event was the break of the probe head due to material failure. The measurements of the drilling sludge, the well and the vicinity of the wellhead showed no traces of 241-Am contamination indicated that the source remained intact. The break of the probe head was in such a place that the available emergency probe retrieving equipment (overshot assembly) and procedure could not be used immediately. The successful retrieval of the sealed source was only possible on the 06th of February 2019 using a modified retrieval technology based on the approval and oversight of the regulatory body with the involvement of a subcontractor licensed for such an activity. According to the first results of the measurements and the in-filed inspections, the sealed source was safely recovered and no indication of radioactive material release into the environment was found.

Location: Pécs
Event date: Mon, 21-01-2019
Nuclear event report
Legenda & explanation