The majority of U.S. underground natural gas storage wells are close to population centers and use a problematic design, according to Harvard University researchers.

Lead author Drew Michanowicz said the information should "stimulate more zoning and planning discussions around energy facilities, especially around setbacks and reverse setbacks."

Michanowicz told NGI that the study did not include Aliso Canyon underground storage field in Southern California, site of a historic four-month-long methane leak, because the nearest well to a home is more than a mile away. The latest study, funded by the Environmental Defense Fund and the Heinz Endowments, looked at wells and homes 200 meters apart. However, the wells are in many cases similar to the single-point-of-failure design (SPF) at Aliso.

The federal Interagency Task Force on Natural Gas Storage Safety, created in 2016, has recommended that the SPF well design used on thousands of wells should be phased out.

Using a population census data analysis model, Harvard’s seven-member research team concluded that “tens of thousands of homes and residents are likely located within the proposed gas storage wellhead safety zone (200 meters), and in some cases within state-designated oil and gas well surface setback distances of active storage wells."

The report took data from 169 underground storage facilities in the six states, collectively representing 9,834 storage wells, 454 of which were visually verified. The team analyzed data from California, Michigan, New York, Ohio, Pennsylvania and West Virginia.

"Sixty-five percent of the storage wells across the six states occupy residential, urban and suburban areas with 41% containing at least one home within 200 meters," the report noted.