Federal safety agency investigating I-85 bridge fire

This image from Google Maps Street View shows the spools of high-density polyethylene conduit in September 2014, stored under the portion of I-85 that collapsed last week. The conduit is blamed as causing the fire to burn hot enough to collapse the bridge.

This image from Google Maps Street View shows the spools of high-density polyethylene conduit in September 2014, stored under the portion of I-85 that collapsed last week. The conduit is blamed as causing the fire to burn hot enough to collapse the bridge.

The Georgia Department of Transportation was more concerned about the spools of plastic and fiberglass conduit under the I-85 bridge being stolen than they were it catching fire and causing a devastating collapse, officials said.

GDOT Commissioner Russell McMurry told the The Atlanta Journal-Constitution Tuesday that the fencing around the conduit material was there more to keep the material in than to keep people out.

As the AJC reported Tuesday, DOT left the tons of conduit under the bridge apparently untouched for several years. The AJC also learned Tuesday that the National Transportation Safety Board, with GDOT's cooperation, is investigating the storage of the material under the bridge and will report its findings to the Federal Highway Administration and the state.

A homeless man has been arrested and charged with arson. Police say he lit a chair on fire last week, which then ignited tons of the high-density polyethylene conduit, which then burned hot enough to collapse the bridge.

“The gating and fencing was really to keep the material from being stolen,” McMurry said. “Obviously, from what we know now, we would not have stored the material in the fashion it was stored in.”