Petrified Forest National Park overlies about 1/4 of the Holbrook basins massive potash deposit in eastern Arizona, but mining and even exploration are off limits on park lands. So, companies are drilling on state and private lands surrounding the park. [right, potash salts. Credit, USGS]
Contrast that to the United Kingdom, where the North York Moors National Park Authority gave permission to Sirius Minerals to begin drilling on park lands to explore Britain's largest potash deposit.
The Yorkshire Post reports that "The exploratory drilling is due to be carried out during the height of the summer season, prompting concerns from tourism businesses that trade will be affected. But senior officers at the national park authority maintained that there was “no factual evidence” that the drilling would have an adverse impact on the tourism sector"