Jeff Brady

The day after his inauguration, President Trump placed a call to the acting head of the National Park Service, Michael Reynolds.

"I can confirm that the call took place. I can't comment on the content of the conversation," National Park Service spokesman Tom Crosson said in an email to NPR.

Trump reportedly was upset over the agency's retweeting of side-by-side photos that unfavorably compared the crowd sizes at his and former President Obama's inaugurations. The retweet was later removed.

When former Texas Gov. Rick Perry faces the Senate Committee on Energy and Natural Resources for his confirmation hearing on Thursday, his first test could be whether he remembers the name of the agency he's been picked to head.

The U.S. Department of Energy is considering the future of a public asset worth tens of billions of dollars: the Strategic Petroleum Reserve.

The Environmental Protection Agency says it has found no evidence that hydraulic fracturing — better known as fracking — has led to widespread pollution of drinking water. The oil industry and its backers welcome the long-awaited study, while environmental groups criticize it.

Update at 7:35 p.m. ET: The Senate voted against completing the Keystone pipeline.

The remaining portion of the Keystone pipeline project, if completed, will be fewer than 1,200 miles long — just a fraction of the existing 2.6 million miles of oil and gas pipelines running beneath our feet in the United States.

The U.S. is in the middle of an oil drilling boom that few people saw coming. After decades of decline, crude oil production is rising again. Technologies such as hydraulic fracturing in places such as North Dakota are getting a lot of attention. But the Gulf of Mexico still accounts for more than one-fifth of domestic oil production.

A remarkable transformation is underway in western North Dakota, where an oil boom is changing the state's fortunes and leaving once-sleepy towns bursting at the seams. In a series of stories, NPR is exploring the economic, social and environmental demands of this modern-day gold rush.

North Dakota's oil boom isn't just about oil; a lot of natural gas comes out of the ground at the same time. But there's a problem with that: The state doesn't have the pipelines needed to transport all of that gas to market. There's also no place to store it.