For a wind farm near Lawton, OK, many of the foundations consist of rock sockets 19 feet in diameter, 20 feet deep. The rock was blasted to presplit the holes and facilitate excavation. The bedrock in the area was so shallow that blasting was needed to construct the access roads, removing the high spots and providing material to fill in the low. In areas where the bedrock was deeper, spread footings were used. [Source: National Driller. Image: National Driller]
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