Had further explosions at the Chernobyl nuclear power station on 26th April 1986 not been contained, and continued to escalate, vast parts of Europe would still be uninhabitable. And would have remained so for the next 20,000 years. The death count over the last thirty years would have been in the millions and not the hundreds, or the thousands, as variously reported now. Depending on the source of the statistic. However, the long-term health consequences were (are?) very real:
“’The exact number of victims may never be known, but 3 million children require treatment,’ said UN secretary-general, Kofi Annan. ‘Not until 2016, at the earliest, will be known the full number of those likely to develop serious medical conditions.’”
In the introduction to Failure to Learn – the BP Texas City Refinery disaster, Andrew Hopkins (referring to Trevor Kletz), writes “…that organisations have no memory, only individuals do. But individuals eventually move on, taking their knowledge with them.” Taking that further, what happens when those with the memory of past events stay and say nothing? And the knowledge, the wisdom, the Lessons Learned is not paid forward? It was a key factor with Chernobyl and the knowledge and information of previous contained events in the [then] Soviet Union and examined by Serhii Plokhy. 
Given the circumstances of the initial explosion, and the subsequent and oft tragic attempts to contain the initial event, this was probably the best outcome we could have hoped for. Had there been a second, more devastating explosion, the potential for wide-spread catastrophe was greater. Much greater. This was one unit of four at the power station.
The recent HBO 5-part series “Chernobyl” has once again not just raised for discussion the safety and viability of nuclear power, it raised and presented the consequences of the absolute failure of leadership. Leadership failure at every level, from ‘shop floor’ to the highest leadership in the country. The consequences of poor leadership, poor communications, and the irony that the exercise of the abuse of power over the workplace, lead to the exercise of power over humanity, and took Toxic Management to a whole new level.
 Times Higher Education. 19 April 2006. https://www.timeshighereducation.com/news/effects-of-chernobyl-worse-than-expected/202727.article Accessed online – 5/11/2019
 Hopkins, Andrew. Failure to Learn. CCH Australia Ltd., Sydney. 2016. p8. Citing – “Kletz, T. Still going wrong! Amsterdam, Elsevier, 2003, p.210”
 Plokhy, Serhii. Chernobyl History of a Tragedy. Penguin Books, London. 2018.
 Plokhy, Serhii. Chernobyl History of a Tragedy. – p xii
 Wikipedia – “Toxic Leader” – A toxic leader is a person who has responsibility over a group of people or an organization, and who abuses the leader–follower relationship by leaving the group or organization in a worse condition than when they first found them.[…] Their leadership style is both self-destructive and ultimately corporately harmful as they subvert and destroy organizational structures.