a tool and method for plugging a service connection to a gas main in preparation for removal of the service tee removes the perforator , mills the hole in the main to provide a smooth seat for a sealing plug , and inserts a gas - tight sealing plug into the hole . the tool of the invention is operable through a narrow &# 34 ; keyhole &# 34 ; excavation , which decreases the risk to service personnel and significantly reduces costs of repairing the excavation . in the preferred embodiment the tool is loaded with a milling bit and a sealing plug before attachment to the service tee . the tool head is engaged to the service tee in a gas - tight fit to prevent the escape of gas during the procedure , and an adapter plate is pivoted between three working positions to perform the three steps of the service connection plugging method . in the preferred embodiment a pneumatic gear motor drives a hexagonal driver bit actuated by a linear actuator located in the shaft of the tool , the driving bit providing the required mechanical interface with each of the accessories involved in each step of the procedure . a separate pneumatic motor pivots the adapter plate between working positions , and specialized adapter is provided at each working position of the adapter plate allowing the same actuators to be used for the perforator removal , milling and plugging operations .