Two San Francisco residents filed a lawsuit Tuesday against the construction company and contractors involved in a gas line rupture that caused a three-alarm fire earlier this month on Geary Boulevard. According to the suit, plaintiffs Carina Kouyoumji and Nora Wixom are suing Mastec Services Company Inc.; Mastec Renewables Construction Company Inc.; Kilford Engineering Inc.; and Advanced Fiber Works Inc. Verizon Communications Inc. has also been named as a defendant. Both plaintiffs live in one of the five buildings badly damaged by the Feb. 6 fire, which ignited after workers installing fiber optic lines near Geary Boulevard and Parker Avenue struck a PG&E gas line. The lawsuit alleges the explosion was a direct result of the defendants’ “reckless and willful violation of California law of using a backhoe to dig a trench near subsurface installations.”