DENVER (AP) — Colorado regulators started work Thursday on new rules for thousands of pipelines that crisscross oil and gas fields in the state after a fatal home explosion blamed on a gas leak.

The state Oil and Gas Conservation Commission outlined the goals for the new rules in a brief meeting with industry representatives and the public.

Some energy company officials raised questions about how much it will cost them to comply with the rules and how many kinds of pipelines the rules will cover.

The rules will apply to flow lines, which carry oil, gas and wastewater from wells to tanks and ot...