(NAPSA)—Think that your house is high-maintenance? Imagine, then, what it would be like to maintain Mount Rushmore National Memorial in South Dakota, the memorial to the growth of America that features 60-foot busts of presidents Thomas Jefferson, George Washington, Abraham Lincoln, and Theodore Roosevelt. As one might imagine, it is a complex, laborintensive, and expensive process. National Parks, the magazine of the National Parks Conservation Association (NPCA), recently spoke to Jim Popovich, chief of interpretation at the memorial, about the preservation of the site’s famousfaces. Q: How often do mainte- nance projects on the sculpture take place? A: We perform an annualinspection of the sculpture each September. [About ten years ago,] we completed a structural stability study on the sculpture, using aerial photos and plotting the whole mountain, which identified 141 cracks. Q: What was the plan to fix the cracks? A: A silicone caulk was the best material we could find. It’s much more flexible and allows us to add some backing rod material into the crack and fill above that. We can color it or just add granite toit. Q: How do you keeptrack of the sculpture’s condition? A: Thereare actually about 21 separate blocks of granite that make up the sculpture. They intersect with most of the 141 known cracks. We began to monitor the rock blocks, which allows us to see if there are any problems with the mountain. Probes go down into the rock and measure the width of a crack, temper- ature, and more. We will run data for the next several years, which should tell us if there are long-term problems with the mountain. Over the years, routine mainte- nance has helped keep Mount Rushmorein shape. Q: How muchdoesthat cost? A: The monitoring system is $55,000 annually. Maintenance work on the mountain itself varies, depending on what needs to be done. Maintenance work usually takes two people. One person goes down the front of the sculpture to do the inspections and the otheris available for safety. Q: How long does the maintenance project last, and do park visitors see it? A: We typically perform this activity over a couple of days. The first day is setup and rigging of equipment, plus we use this opportunity to invite media to meet the crew and ask questions. Q: Is the sculpture cleaned? A: No. The memorialis exposed to the elements of nature that keepit clean. Q:Do visitors ask about maintenance? A: They do, certainly. When visitors first view the memorial, they comment about how immense it is. Second, they begin realizing what it means to our country. Only after these two observations do they begin to understand how it is maintained and what a magnificent feat it wasto carveit. For more information about the national parks and the National Parks Conservation Association, go to www.npca.org.
