CHEYENNE, Wyo. (AP) — The owner of a central Wyoming gas field where the U.S. Environmental Protection Agency has theorized a link between a petroleum industry technique and groundwater pollution has asked the EPA to suspend taking public comments on the draft report.

Encana says in a letter to the EPA that the agency didn't make clear which topics the comments are supposed to cover. The company also is seeking more of the data that went into preparing the document.

EPA officials said Monday they are reviewing the letter.

At issue is whether hydraulic fracturing, or fracking, contaminated groundwater in the Pavillion gas field in Fremont County. Fracking involves pumping pressurized water, sand and chemicals into oil and gas wells to fracture rock.

A 45-day public comment period on the report closes Jan. 27.