MINNEAPOLIS (WCCO) — At Minnehaha Academy the buildings have been rebuilt, but the memories of that horrible day when nine people were injured and two killed remain.

A 10-page report says the two employees of Master Mechanical did not have the training required and were not qualified to move the gas meter from inside the basement to outside the building – the job they were trying to do.

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The report says the two workers, a father and son duo, thought the gas pipe they were working on was shut off when it was in fact on and open.

The mistake triggered the massive explosion within seconds, killing John Carlson, a Minnehaha graduate who worked as a custodian, and receptionist Ruth Berg. Nine other employees were seriously injured.

The report says in the aftermath of the explosion Center Point Energy revamped its procedures for moving meters from inside to outside a building. Now a lot more steps, and a lot more supervision, are required.

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Master Mechanical gave WCCO a statement saying, “throughout this entire difficult time, we have cooperated fully with the NTSB. We continue to keep in our thoughts all those impacted by the incident.”

There are a number of civil lawsuits by Minnehaha employees, against both Master Mechanical and CenterPoint, that are pending.

A statement by Centerpoint says they already reached settlement agreements with the families of the two people who died, as well as the person most seriously injured.

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Minnehaha Academy issued a statement, saying: “We appreciate the comprehensive work of the NTSB. As the report makes clear, Minnehaha Academy has no culpability in this tragic event. Since this report relates to an open legal matter, we cannot comment further.”

Esme Murphy