A geyser of flame erupted at a construction site in Long Island City Saturday after a construction crew’s drilling rig hit a high-pressure gas line.

The two-alarm fire was contained to the rig and did not spread — though it was hot enough to melt a nearby factor’s windows, said FDNY Division 14 Deputy Chief Patrick Sheridan.

Workers at the former West Chemical Company site said the gas line was not marked, but they smelled gas after hitting the drill and fled before the fire.

One worker suffered a minor injury. The Fire Department is investigating.

New York developer Tishman Speyer is building a 42-story apartment tower on the site.