DENVER — Proposition 112 is a voter initiative that would make most new oil and gas development in Colorado be at least 2,500 feet away from homes, schools, buildings and more.

Most new currently wells must be at least 500 feet away from homes and 1,000 feet away from schools and buildings.

But that wasn’t always the case.

For most of the 20th century, the location of oil and gas wells was dictated by land and mineral rights. But that changed with directional drilling.

In 1985, the Colorado Oil and Gas Conservation Commission created the first official setback.

It said most new wells had to be at least 150 feet away from homes and buildings.

That rule was put in place in case an oil rig toppled over.

As oil and gas developments increased, more people started speaking out and wanted them to be farther from homes.

In 1992, the commission made a new setback of 350 feet for high-density areas, including neighborhoods. In 2013, the setbacks become stricter.

The commission moved them to where they are today — where most new wells must be at least 500 feet from homes and 1,000 feet from schools and buildings.

“It’s just trying to make sure we are continuing to regulate the industry responsibly and make sure those setback distances are appropriate,” said COGCC environmental manager Greg Deranleau.

Also, in 2015 the commission created new rules to make oil and gas companies talk with communities earlier in the process when they want to drill new wells.

“One of the big concerns was the local governments are sort of shut out of the permitting process until pretty late in the game and this kind of turned that around,” Deranleau said.

Oil and gas companies can petition the commission to have oil and gas wells closer, but that requires a public hearing and rarely happens.

Also, these rules are for oil and gas wells getting built next to existing homes, schools and buildings.

The commission does not regulate the opposite — homes and buildings being built next to existing wells.