CHATHAM COUNTY, N.C. — Despite being in one of the nation’s fastest-growing states, this rural county of roughly 85,000 people is still brimming with red foxes, coyotes, white-tailed deer, and wild turkeys.

But in recent months, Enbridge Gas North Carolina’s proposed plans for a natural gas pipeline have exposed how population growth, here and across the nation, is driving a divide between wealthy newcomers and longtime residents.