At approximately 1025 hrs (10:25 am), Station 5 was alerted to the 3200 block of Phoenixville Pike for a reported gas leak outside. The initial caller indicated an above ground storage tank was possibly leaking propane. Within minutes however, Chester County 9-1-1 received supplemental information that the tank was approximately 20'-30' long with an active leak, and the tank was approximately 10 ft from an adjacent occupied commercial building. With this information, Chester County Fireboard upgraded the response to a Hazmat Box assignment, re-alerting the full company from Station 5, and adding a medic from station 4 (Malvern) as well as Station 15 (Chester County Hazmat Team).

Firefighters quickly arrived on location and confirmed the active leak and started taking defensive measures. The surrounding property in the area was evacuated as a precaution, and Phoenixville Pike was shut down to limit possible ignition sources from passing vehicles. Firefighters stood by at the ready in case of a fire or explosion, and monitored the leak. Hazmat Technicians from Station 15 arrived and began their assessment of the leaking tank to determine the cause and extent of the leak. The leak was determined to be from overfilling of the tank with damage to the emergency relief valve preventing closure after pressure had been reduced. The gas company responded and proceeded to off-load the tank into another vessel.

The situation was put under control by 1330 hrs (1:30 pm).