The largest concentration of natural gas in North America — 40 trillion cubic feet — is trapped in underground coal seams in the southwestern United States.

It is also one of America's most scenic spots, so it has ignited a battle between those who want the energy and those who want to live there.

La Plata County in Colorado is renown for its beauty, outdoor sports and peaceful solitude, but that's all changing.

Since the price of natural gas doubled 18 months ago, oil and gas companies are drilling as never before.

"We've seen a steady increase in the number of permits that have been applied for and ultimately approved in the county, so we're seeing an increase in drilling activity," says Adam Keller, a La Plata County planner.

Pump jacks are everywhere — even on private property. That's because Colorado, like most western states, allows separate ownership of property on the surface and the mineral rights below.

Property Owners Only Have Surface Rights

But in many cases, property owners are surprised to learn about the separate ownership of mineral rights. They are also angry that no one told them about the pump until it was too late.

Leo and Ann Epstein built their retirement home in La Plata County seven years ago. Recently, while they were out of town, a noisy compressor plant (part of the pump) was installed next door.

"We love our home," says Leo. "We have wonderful neighbors on [one] side. This side is whole different story," he says pointing to the plant.

And David and Pati Temple, who own a tree farm, installed an expensive filtration system because they say their ground water was being polluted.

"The methane contamination of our water has created an anorbic state," said David Temple. "We have now four different bacterias that are living in the water and we have to kill them and clean up the mess they make so our water is potable."

Industry: Know What's Below Before You Buy

Drilling companies, which own or lease mineral rights, have been extracting natural gas here for 50 years. But now that business is booming, they say it's up to property owners to make sure they are not sitting on top of a natural gas deposit.

"They need to recognize the rights that they have when they buy their property because natural gas is being developed here and it's important to our economy," says industry spokesperson Gail Aalund.

"It's just the antithesis of what we came out here for," explains Leo. There are "lots and lots of trucks, day and night," concurs his wife, Ann.

"Certainly it's a mixed bag for the county," says Keller, referring to the fact 45 percent of the county tax base is from natural gas. "There [are] some good economic resources we get from it, based on taxes, but it's also a place where people live and residences get impacted by the drilling."

In last decade, new residents have been attracted to La Plata County because of the promise of peace and quiet. But with the recent approval of more than 600 new drilling sites, more homeowners are about to discover a pump jack, storage tank, or compressor in their back yard.