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Lava-Cooling Operations During the 1973 Eruption of Eldfell Volcano,
Heimaey, Vestmannaeyjar, Iceland
U.S. Geological Survey Open-File Report 97-724
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Manpower In the beginning of April, when the lava-cooling reached its peak, about 75 men were working on the cooling operation. In May, the number of workers had decreased to 40-50, and by the beginning of June only about 30 were involved. Most often the method used was to have the men work for 13 consecutive days from 8 a.m. to 10 p.m. and then give them 2 days off with full pay. Machine tending and crater watch was done in shifts. Engineers, supervising the operations, worked one week in Vestmannaeyjar and spent the next week on the mainland. This method was used to avoid fatigue and also because they had other duties [e.g., their regular jobs]. Table 2 indicates how the manpower was divided during this time; the figures show the number of workers for each month. The item in the table called crater watch may draw special attention. The reason for this watch was that, on 26 April, lava flowed from the crater along a gorge, which had formed on the western edge of the lava flows. No one noticed the lava flow until it had stopped by itself. It was then decided to lay pipes connected to fire hoses along the edge of the gorge to spray water over the lava, in case it started to move again. This pipe reached closer to the crater than any of the others, or approximately a 150-m distance from the edge of the crater.
The crater watch was conducted day and night from then on in order to avoid a recurrence [of
a missed lava flow]. The men responsible for the crater watch catalogued the behavior of the
eruption, until the crater watch was eliminated on 3 July.
It is hard to describe the difficulties involved in placing the pipeline network on the red-hot lava, and the risk the men took who did the work. A small example will have to suffice. The first step in bringing piping up from Sólhlíð, close to the new hospital, was to build a new road up onto the lava edge. This was done by pushing together tephra which was abundant. The first day the road was built on a 25-30-m-high edge and [extended] 5-6 m onto the lava. The following day, this whole stretch [of road] had been transported 10 m to the north, so the work had to be started all over again on that part. When that was completed, plastic pipes, 225 mm [9 in] in diameter, were hauled up onto the lava and laid approximately 20 meters inward. Pumping was started, as soon as possible, so that the pipes would not melt. This caused a great column of steam to form, which soon spread about 50 meters onto the lava and north along the lava flow. Because of the heat and poor visibility, it became impossible to maneuver in the area. [However,] because of perseverance by the men laying the pipelines, it became possible to travel through the steam with a bulldozer and the use of a walkie-talkie. Another pipeline was laid about 130 meters inward on the lava, directly across the lava advance. During this work, a few men were burned on their hands and feet. When the cooling had continued for a few days, the lava had become widely cracked and rough with a strong sulphur smell. This made all operations exceedingly more difficult. Other difficulties were that the lava edge rose and became much hotter. In some cases, where cooling operations were intense, rifts formed that were 5-6 m deep and 5 m wide. Lava piled up above the cooled areas and fissures which had formed and, in some places, had cracked open the lava crust.
The men adjusted to these difficulties amazingly well, and some of them became extremely
agile in finding their way over the [rough and irregular] lava surface through the steam and
smoke. Thus came into existence a group of hardy men that was called "The Suicide Squad".
No serious accidents happened during the cooling, in spite of such extremely dangerous work. | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||