City and pipeline officials are scratching their heads over a gas discharge detected May 1, approximately 1.5 miles east of the March 3 Panhandle Eastern Pipeline rupture.

Bubbles were detected in the area of the Panhandle Eastern Pipeline, owned by Dallas-based Energy Transfer Partners, during an aerial inspection. The company said the bubbles possibly came from methane leaking from the city’s closed landfill, and are not associated with the pipeline, which is operating normally, the company wrote in a statement.

Methane leakage from the landfill could not be the case, because “Missouri (Department of Natural Resources) has cleared and closed all test wells for methane gases at the old landfill over ten years ago,” the city wrote in a statement. The landfill closed in 1998 and the city has to continue financial and inspection obligations through 2033.

The department also inspects the landfill property yearly and no evidence of methane gas has been detected, City Clerk Marcy LeCount wrote in an email. City staff inspected the landfill site last week and found no evidence of methane gas leakage on city property.

Panhandle Eastern returned to service last month. A ventilation system has been installed to help monitor any other possible gas discharges near the pipeline.

The discharge was found near the property line of the former landfill and a property belonging to Don Feger.

Energy Transfer did not respond to a request for more information by the time of publication. The March 3 rupture occurred approximately one mile north of Mexico near Missouri Highway 15 and was reportedly caused by stress corrosion. The fireball burned for approximately 90 minutes. Total incident cost was estimated at $1.4 million.