DENVER (AP) -- The Colorado Oil and Gas Conservation Commission is considering statewide rules on groundwater sampling and monitoring at new well pads.

The commission on Monday began discussing the state's so-called "setback" rules on how far wells must be from buildings.

The proposed rules could show when drilling operations contaminated groundwater supplies and when they haven't.

One proposal would require a public hearing and commission approval before wellheads can be placed within 750 feet of schools or hospitals.

Opponents are warning that the tough new rules could hurt companies.