| 10/21/2007 |
| Hundreds tour Ames' underground |
| By Bob Zientara , Staff Writer |
Robey had stopped his pickup truck at an intersection of underground roads during a tour of the square-mile-sized mine. It was 8 o'clock in the morning on the surface, and the sun was shining. Here, it looked like night - unless the lights were on. The plant manager waited while a couple of school buses, filled with other mine visitors, turned down another "street." Then, he turned off his headlights. Total darkness overtook the truck and its passengers. "Without a flashlight down here, you'd be in trouble," said Robey, switching the headlights back on and pointing to an emergency flashlight he kept in the cab. Martin Marietta opened the mine to visitors Friday, and from 5 a.m. to 3 p.m., they streamed onto the property by the hundreds. Employees greeted them with bottles of water or cups of hot chocolate, showed a Powerpoint presentation on mine safety and took them into the mine shaft by the school busload. Among the special guests were Iowa Secretary of Agriculture Bill Northey and the broadcast team of Van Harden and Bonnie Lucas, the WHO Radio morning drive personalities who did a live broadcast from inside the mine. Todd Clock, vice president for Martin Marietta's Des Moines district (including parts of Iowa and Nebraska), said the operation started out as an open pit in the 1960s. "But the material near the surface, what we call the 'overburden,' is of poor quality limestone and shale," he said. "The economics of an open pit won't work here. That's why the operation was turned into a mine." Clock pointed to the massive, 30-plus-foot wide pillars that hold up the mine galleries and said they are purposely oversized to ensure safety. Robey said the miners recently opened a deeper shaft and had discovered a new, high-quality vein of limestone. Clock said that mine, including the new and old shafts, "will take generations" to dig out. Robey, who grew up just a couple miles north of Ames and has spent most of his career with Martin Marietta, said that the work is interesting and challenging. "Miners have different kinds of personalities," he said. "Most of the time, everybody gets along well. But if there's a problem, a miner won't be shy about telling you about it." Bob Zientara can be reached at 232-2161, Ext. 487, or rzientara@amestrib.com. Martin Marietta's Ames Aggregate Mine * Size: 640 acres - about a square mile. * Depth: Ranging from about 140 to 200 feet underground. * Work force: 55 full-time miners. * Production: 200,000 to 300,000 tons per month. * Estimated capacity of new (2007) mine shaft: 180 million tons. * Web link: For a presentation Martin-Marietta aggregate production, visit: http://construction.transportation.org/sites/construction/docs/Smith,%20Martin-Marietta,%20Aggregates.pdf Source: Todd Clock,vice president, Des Moines District, Martin Marietta Corporation.
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