The Colorado Oil and Gas Conservation Commission plans to consider the proposals next week.
The proposals would make Colorado the only state to require sampling of water wells near drilling sites both before and after drilling to ensure drinking water aquifers are protected.
Required distances between drilling and buildings would be increased to 500 feet, up from 150 feet in rural areas. A hearing before the oil and gas commission would be required before any drilling within 1,000 feet of schools or other high-occupancy buildings.
The state's rules are being updated as drilling has moved into more populated areas.
(Copyright 2012 by The Associated Press. All Rights Reserved.)