ROSS, N.D. — While three generations of the Sorenson family have made their livelihood growing wheat and other crops here, they also have learned to embrace the furious pace of North Dakota’s oil exploration. After all, oil money helped the Sorensons acquire the land and continue to farm it.

But more oil means more drilling, resulting in tons of waste that is putting cropland at risk and raising doubt among farmers that these two cash crops can continue to coexist.

A private company is trying to install a landfill to dispose of solid drilling waste on a golden 160-acre wheat field across the road from Mike and Kim Sorenson’s farmhouse. Although the engineers and regulators behind the project insist that it is safe for the environment, the Sorensons have voiced concern that salt from the drilling waste could seep onto their land, which would render the soil infertile and could contaminate their water, causing their property value to drop.

“I’m concerned not if it leaks, it’s when it’s going to leak over there,” Ms. Sorenson, 42, said.

Oil companies in North Dakota disposed of more than a million tons of drilling waste last year, 15 times the amount in 2006, according to Steven J. Tillotson, the assistant director of the Division of Waste Management for the state’s Health Department. Seven drilling waste landfills operate in the state, with 16 more under construction or seeking state approval.