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Humble Pi

My Summary

Highlights

In 1980 the Texaco oil company was doing some exploratory oil drilling in Lake Peigneur, Louisiana. They had carefully triangulated the location to drill down to look for oil. Triangulation is the process of calculating triangles from fixed points and distances in order to locate some new point of interest. In this case, it was important because the Diamond Crystal Salt Company was already mining through the ground below the lake and Texaco had to avoid drilling into the pre-existing salt mines. Spoiler: they messed up the calculations. But the results were more dramatic than what you’re probably imagining. According to Michael Richard, who was the manager of the nearby Live Oak Gardens, one of the triangulation reference points was wrong. This moved the oil drilling about 120 metres closer to the salt mines than it should have been. The drill made it down 370 metres before the drilling platform in Lake Peigneur started to tilt to one side. The oil drillers decided it must be unstable, so they evacuated. Arguably, the salt miners had an even bigger surprise when they saw water coming towards them. The drill hole was only about 36 centimetres across, but that was enough for water to flow from Lake Peigneur down into the salt mines. Thanks to good safety training, the mining crew of about fifty people was able to evacuate safely. But how much water could the mine take? The lake had a volume of around 10 million cubic metres of water to give. But the salt below had been mined since 1920 and the mines now had a volume greater than the volume of the lake above. As the water gushed down, earth was eroded and salt dissolved. Soon, the 36-centimetre hole had become a raging whirlpool 400 metres in diameter. Not only did the entire lake empty into the salt mine, but the canal joining the lake to the Gulf of Mexico reversed direction and started to flow backwards into the lake, forming a 45-metre waterfall. Eleven barges which were on the canal were washed into the lake and dragged down into the mine. Two days later, the mine was completely full and nine of those barges bobbed back to the surface. The whirlpool had eroded away around 70 acres of nearby land, including much of Live Oak Gardens. Their greenhouses are still down there somewhere … Because of the miscalculation of a triangle, a freshwater lake which was only about 3 metres deep was completely drained and refilled from the ocean. It’s now a 400-metre-deep saltwater lake, and this has brought a complete change in plants and wildlife. Amazingly, there was no loss of human life, but one fisherman out on the lake did have the fright of his life when the peaceful water suddenly opened up into a raging whirlpool. — location: 1223



Created by Niall Bell (niall@niallbell.com)