Officials with the site in Hot Springs plan to build a 5,800-square-foot addition that will feature a new entryway, gathering area, storage, and two 53-seat theaters.
Business manager Joe Muller says the funding will give South Dakota a world-class working paleontological site and museum. About 100,000 people visit the site each year.
An official with the U.S. Department of Agriculture announced the funding during a site visit Thursday.
At least 60 mammoths have been found in the area. The site has been under exploration since 1974, when a construction crew dug up mammoth bones on the south side of Hot Springs.
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