Around 1100 units were dispatched to N38th st and Linden street for an odor of gas outside, called in by UGI. Engine 311 responded w/4,arrived shortly after and started to check the area with meters. UGI found high levels around the outside of a residence and requested to force entry to check the home. Crews forced entry into the non occupied house where UGI found a major leak underground. Engine company set up ventilation as UGI went to work fixing the leak. Crews cleared 30 minutes later and the incident was handed over to UGI.