Trevor Walczak is concerned about the environmental impact of natural-gas companies drilling on his land in eastern Pennsylvania, but $342,000 in this economy was too good to pass up.

"This type of windfall gives everybody a great opportunity for the future -- it's multigenerational," says Mr. Walczak, who recently sold lease rights on 163 acres for $2,100 an acre to Ohio-based North Coast Energy Inc.. "Just the ability to become debt-free is a huge leap for somebody."

The 31-year-old forester, whose family owns a sawmill, thinks worries about how drilling will affect water supplies are overblown. He plans to use his windfall to invest in a quarry.

Thousands of other Pennsylvanians are making a similar calculation. In the current economic squeeze, financial opportunity is outweighing environmental issues for people swept up in a land grab by energy companies targeting gas reserves thousands of feet beneath people's properties.

Companies eager to secure rights to drill into a deep stratum of shale known as the Marcellus deposit are paying as much as $2,500 an acre, or more, in some parts of the state, up from $25 an acre a year and a half ago, for five-year leases. Meanwhile, royalty rates, which are paid once production starts and could eventually lead to far greater income for mineral-rights owners, have risen to 18% of production revenue in some cases, compared with the state-mandated minimum of 12.5%.

In many cases, energy companies are targeting rural areas that have been depressed for years. "These payments are a real godsend to these people," says Tim Considine, a professor of natural-resource economics at Pennsylvania State University.

Rising natural-gas prices and new technologies have led to a boom in natural-gas drilling in other states, including Texas, Colorado, North Dakota and Louisiana (See related article). Many landowners there are seeing offers as rich or richer. Some offers in the Fort Worth, Texas, area have run above $25,000 an acre.

"We have 15 buildings on our farm, and every single one of them is in some sort of major need of repair," says Marian Schweighofer of Damascus, Pa. She says her family, which is the sixth generation of Schweighofers to grow corn and hay and raise cattle and sheep, is close to finalizing terms to sell the rights to drill on its 712 acres. The family plans to use the money to replace old equipment, including a 42-year-old hay baler. She says she would rather have a small tower on a few acres of her property than lose the money needed to keep the farm going.

She and her neighbors are negotiating as a group owning 70,000 acres -- not only for environmental reasons, but also to avoid friction over money. "If you signed for $25 and I signed for $50, you were angry at me," she says. "It pitted one neighbor against another."

People in rural parts of the state who rely on the land to maintain dairy farms or hunt worry they will have to deal with the kind industrial activity that communities out West have already faced from natural-gas projects, from increased truck traffic and air pollution to pipelines and other changes to the landscape. In some cases, ranchers have joined with environmental groups to fight noise pollution from pumps as well as dust from trucks and drilling.

The big environmental issue is water. Large amounts of pressurized water are needed to fracture rock thousands of feet underground. Once the rocks are free, the gas can flow to the wells. Not only will more of the state's water be channeled to mining, but some people worry the process could also contaminate wells or parts of the state's aquifer. Last month, officials at the Pennsylvania Department of Environmental Resources shut two new natural-gas wells in the absence of permits to extract water from local streams.

Elizabeth Downey is leaving her concerns about the environment to the state. "With all of the agencies watching them, I've got confidence that they'll do the right thing," says Mrs. Downey, who got a check for nearly $160,000 after selling the lease rights on 105 acres near Jersey Shore, Pa., for $1,500 an acre.

Energy companies say they are eager to work with the state's regulators, as rules are developed specifically for areas of the state where drilling is new.

Some landowners are concerned that too much attention to environmental concerns could delay or wipe out royalty opportunities. Louis Matoushek, a 66-year-old former dairy farmer in Clinton Township, sold the lease rights on 195 acres for $125 an acre last August. With a well already on his property, he thought royalty payments would soon follow. But he says action stopped just as the company was about to use water to fracture the rock.

"One of my biggest fears is that this state is going to have rules and regulations that are so tough on the drillers that they're going to move," he says.

Write to Kris Maher at kris.maher@wsj.com

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