A report done for a Colorado oil and gas trade group says proposed new state regulations could cost natural gas customers billions of dollars over the next decade.

The report commissioned by the Colorado Oil and Gas Association says the proposed rules could slow down approval of new natural gas wells and facilities, limit when companies can drill and increase operating costs.

The report says that could boost natural gas prices by up to $1.7 billion in Colorado over the next decade and up to $32 billion nationally.

State officials and environmentalists question the report's findings and assumptions.