Thursday, December 14, 2017
The Iron Mine was constructed in 1964. "During operation, it extracted as much as 1 million ton of rock each year. The iron ore extracted here was crushed to a size less than 1 1/2 ft. in the underground crusher. It was then hoisted to the surface and fed into a secondary crusher that took it to a size less than 6 inches. It then went into a tertiary (3rd) crusher that took it to a size less than 1 inch. After that, it went into the wet milling circuit. The mills ground the ore down to where 90% would pass through a 325 mesh screen (for the primary product). It then went through a flotation circuit to separate the impurities out. There were a few different processes after that to produce different products. Most was sold to Coal companies for use in purifying coal. Some was sold to magnet companies. Some was converted to hematite and sold for other uses".
"The elevator was a 20 ft x 14 ft metal box with a normal operating speed of ~60 ft per sec. going up or down. The tunnels started at 1600 ft. down where the ore body began. Every 50 ft. to 75 ft. after that is another fan of tunnels, with inclines from one level to another. The crusher was located 2400 ft. deep and a half mile long conveyor belt took the crushed material up to the hoist skips at 2000 ft. Each skip was filled to approx. 60 tons and that was hoisted straight up to the surface". These hoists were powered by 1,000HP General Electric Induction motors.
The Iron Mine ceased all operations in the early 2000's due to the price of imported iron being roughly equal the cost of extracting the ore here. The mine naturally filled with water when the pumps were shut off, as they pumped around 1/2 a million gallons out every 24 hours during operation. The mines are now flooded and, based on careful scientific tests performed by my comrades and I on a recent visit, we determined that the water level is about 300 feet down from the surface.
A former employee provided most of the information above regarding day-to-day operations.
Click here for the video.
