By the time of this report, Ukraine had declassified a number of KGB documents from the period between 1971 and 1988 related to the Chernobyl plant. It mentioned, for example, previous reports of structural damage caused by negligence during construction of the plant (such as splitting of concrete layers) that were never acted upon. They documented more than 29 emergency situations in the plant during this period, eight of which were caused by negligence or poor competence on the part of personnel.